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Triassic doig formation sand bodies in the Peace River area of western Canada : depositional and structural… Harris, Richard Gordon 2000

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TRIASSIC DOIG FORMATION SAND BODIES IN THE PEACE RIVER AREA OF WESTERN CANADA : DEPOSITIONAL AND STRUCTURAL MODELS, AND THE IMPACT OF DIAGENESIS ON RESERVOIR PROPERTIES by RICHARD G O R D O N HARRIS B.Eng. (Hons.), Queen's University, 1990, 1997 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE D E G R E E OF MASTER OF SCIENCE in THE FACULTY OF G R A D U A T E STUDIES Department of Earth and Ocean Sciences We accept this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA February 2000 '••>;. © Richard Gordon Harris, 2000 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department The University of British Columbia Vancouver, Canada DE-6 (2/88) ABSTRACT Middle Triassic Doig reservoirs in the Fireweed, Buick Creek, Cache Creek and West Stoddart fields (94-A-13 to Twp.86, Rge.18) of northeastern British Columbia consist of deltaic and shoreline sands encased in shelf and offshore mudstones and siltstones. The reservoirs comprise a series of northwest and northeast trending elongate sand bodies that lie along a south-southeast depositional trend analogous to the position of the original Doig shoreline. Sediments of the Doig Formation are divisible into two facies associations and ten lithofacies representing deposition in shelf to offshore, and deltaic and inter-deltaic environments. Hydrocarbon producing intervals consist of clean, very fine to fine grained, sub-lithic to quartz arenites, inter-bedded sandstones and bioclastic detritus, and disseminated bioclasts. Effective porosity is primarily inter-granular in the sandstone facies with significant moldic and intra-granular porosity developed in the coquina facies at the West Stoddart and Cache Creek fields. Average porosities range from 6.5 - 9.5% for sandstone lithofacies and 4.9 - 8.6% for coquina lithofacies. Pore occluding cements are mainly calcite in the northwest part of the reservoir trend to dolomite and anhydrite in the southeast. The sedimentology and facies architecture of recent discoveries at Cache Creek and West Stoddart contrast with those identified in previous studies of Doig reservoirs at Buick Creek in northeastern British Columbia and Sinclair in west central Alberta. A three-dimensional facies model of the Doig Formation at the Cache Creek, West Stoddart and Fireweed fields depicts sandstone deposition in a deltaic environment as distributary channel fills and slumped delta front deposits. Data for the Buick Creek field ii confirms and extends the incised shoreface model to include fluvial or tidal channels deposited laterally continuous in the same systems tract as the shoreface sands. Sand bodies for all four fields were deposited contemporaneously as the Doig shoreline prograded over mudstones and siltstones of the Doig shelf. Seismic and well data reveal tectonic control on the position and orientation of the Doig reservoir trend. Syn-sedimentary growth faults control the location and geometry of thick sand bodies along the reservoir trend in the Fireweed area. Diagenetic controls along the reservoir trend include the precipitation of calcite in the near surface and shallow burial realm, fracturing of cemented horizons prior to extensive burial and dissolution of cements and framework grains in three distinct episodes. Multiple dissolution phases created moldic, vuggy and inter-granular secondary porosity. Reservoir quality and production from Doig Formation sand bodies in the Peace River area of Western Canada are significantly impacted by the preservation of inter-granular porosity and fracturing related to the distribution of early calcite cements. The early calcite cements were sourced from bioclastic debris and calcareous mudstones distributed during sand body deposition. The formation of open fractures during early diagenesis enhanced both the secondary pore network and the permeability of the West Stoddart and Cache Creek Doig pools. Sand bodies with only minor interstitial calcite have extensive porosity loss by compaction and precipitation of authigenic quartz. A fairway for Doig sand body exploration is constrained by production and core analysis data, structural and depositional models, thermal maturity data and diagenesis. iii TABLE OF CONTENTS Abstract ii Table of Contents iv List of Figures viii List of Tables x Acknowledgements xi C H A P T E R 1 - INTRODUCTION 1.1. - Introduction 1 1.4. - Structure of Thesis 2 1.5. - References Cited 3 C H A P T E R 2 - DEPOSITIONAL AND S T R U C T U R A L MODELS FOR DOIG FORMATION SAND BODIES IN THE P E A C E RIVER A R E A OF N O R T H E A S T E R N BRITISH COLUMBIA 2.1. - Abstract 4 2.2. - Introduction 5 2.3. - Geologic Setting 6 2.4. - Lithostratigraphy and Sand Body Geometry 10 2.4.1. - Facies and Facies Associations 12 2.4.2. - Cross-sections and Facies Architecture 14 2.4.2.1. - West Stoddart and Cache Creek 14 2.4.2.2. - Fireweed 16 2.4.2.3. - Buick Creek.... 19 iv 2.5. - Depositional Setting 21 2.5.1. - Interpretation of Fades and Fades Assodations 21 2.5.2. - Depositional Models for Sand Bodies Comprising the Fireweed, Cache Creek, West Stoddart and Buick Creek Pools 25 2.5.3. - Alternative Depositional Environments 31 2.5.3.1. - Tidal Inlets/Barrier Islands 31 2.5.3.2. - Shelf Sheet Sands Incised by Tidal/Storm Channels 31 2.6. - Structural Controls on Reservoir Distribution 32 2.6.1. - Regional Considerations 32 2.6.2. - Deposition of Doig Sands at Structurally Controlled Slope Breaks 35 2.6.3. - Structural Features form Log Data 35 2.6.4. - Syn-Sedimentary Growth Faulting 38 2.7. - Summary and Conclusions 40 2.8. - References Cited 42 C H A P T E R 3 - DIAGENESIS, RESERVOIR QUALITY AND PRODUCTION T R E N D S OF DOIG FORMATION SAND BODIES IN THE P E A C E RIVER A R E A OF W E S T E R N CANADA 3.1. - Abstract 46 3.2. - Introduction 47 3.3. - Lithology and Depositional Setting 49 3.4. - Database 52 3.5. - Petrology of Doig Sandstones 54 3.5.1. - Sandstone Composition 54 V 3.5.2. - Coquina Composition 55 3.5.3. - Diagenesis 55 3.5.3.1. - Calcite Cement 57 3.5.3.2. - Quartz 57 3.5.3.3. - Apatite 59 3.5.3.4. - Dolomite 59 3.5.3.5. - Anhydrite 59 3.6. - Paragenesis 61 3.6.1. - Early Calcite 61 3.6.2. - Fracturing and Microfaulting 63 3.6.3. - Formation of MoldicA/uggy Porosity 65 3.6.4. - Compaction 65 3.6.5. - Replacement of Quartz by Carbonate 65 3.6.6. - Precipitation of Ferroan Calcite 66 3.6.7. - Carbonate Dissolution - Secondary Porosity 66 3.6.8. - Dolomite Precipitation 67 3.6.9. - Hydrocarbon Migration 67 3.6.10. - Geochemical Considerations 67 3.7. - Reservoir Quality 68 3.7.1. - Trend of Porosity and Permeability with Depths 70 3.7.2. - Bioclastic Facies and Calcite Cement Distribution 72 3.7.3. - Distribution of Secondary Porosity 72 3.8. - Production Trends 75 3.9. - Discussion 79 3.10. - Constraints on Exploration 82 vi 3.11. - Conclusions 85 3.12. - References Cited 86 C H A P T E R 4 - CONCLUSIONS 89 APPENDIX A - C O R E IDENTIFICATION AND LOCATION 92 APPENDIX B - C O R E DESCRIPTIONS 94 APPENDIX C - C A T A L O G U E OF THIN SECTION 186 APPENDIX D - C O R E ANALYSIS DATA 190 vii LIST OF FIGURES Figure 2.1. Map illustrating Doig penetrations within pools of the study area and cross-section locations 7 Figure 2.2. Stratigraphic framework for the study area 9 Figure 2.3. Facies associations within the Doig Formation at West Stoddart and Buick Creek 13 Figure 2.4. Section A-A' through West Stoddart field oriented parallel to depositional dip 15 Figure 2.5. Section B-B' through Fireweed, Cache Creek and West Stoddart fields, oriented perpendicular to depositional dip 15 Figure 2.6. Section C - C through Buick Creek field oriented perpendicular to depositional dip 17 Figure 2.7. Total Doig sand isopach within the study area 17 Figure 2.8. Core photographs of Facies 1a, 1c, 2a and 2b 18 Figure 2.9. Core photographs of Facies 2c, 2e and 2f 18 Figure 2.10. Sedimentary features in core photographs of the sandstone and bioclastic lithofacies 24 Figure 2.11. Sedimentological model for the Doig Formation at West Stoddart, Cache Creek and Fireweed fields, northeastern British Columbia 26 Figure 2.12. Dipmeter log through interpreted channel sandstones of the Cache Creek field 29 Figure 2.13. Structural elements intersecting the regional Doig sand trend 33 Figure 2.14. Structure contour map of the top of the Doig Formation upper phosphatic marker 34 Figure 2.15. Doig Formation isopach within the study area 36 Figure 2.16. Stratigraphic Section D-D' located in Fig 7 37 Figure 2.17. 3D seismic line showing middle Triassic growth fault at down-dip edge of the Fireweed delta complex 39 viii Figure 3.1. Location map of the study area showing the reservoir trend 48 Figure 3.2. Stratigraphic framework for the study area 50 Figure 3.3. Total Doig sand isopach within the study area 53 Figure 3.4. Core photographs of calcite cements in Doig Formation sandstone 56 Figure 3.5. Photomicrographs and S E M images of diagenetic phases in Doig Formation sandstones 58 Figure 3.6. Photomicrographs and core images of diagenetic features within Doig Formations sandstones 60 Figure 3.7. Generalized paragenetic sequence and porosity evolution of Doig Formation sand bodies 62 Figure 3.8. Fracture styles in Doig Formation sandstones..... 64 Figure 3.9. Core image and photomicrograph of compaction features 64 Figure 3.10. Graphs of core analysis data versus true vertical depth for various Doig pools 71 Figure 3.11. Map showing the distribution of bioclastic facies 73 Figure 3.12. Porosity/Permeability cross-plots for Buick Creek and West Stoddart 74 Figure 3.13. Production cross-plots illustrating declines for the Buick Creek and West Stoddart pools 77 Figure 3.14. Map showing average daily oil and gas production for Doig pools along the reservoir trend 78 Figure 3.15. Map illustrating the constraints on exploration for Doig Formation sand bodies along the reservoir trend 83 ix LIST OF TABLES Table 2.1 : Lithofacies descriptions 11 Table 3.1. Lithofacies descriptions 51 Table 3.2. Average porosity and permeability values for select fields along the Doig reservoir trend 69 Table 3.3. Decline factors and average production for deviated and non-deviated wells in select fields along the Doig reservoir trend 76 X ACKNOWLEDGEMENTS I would like to thank my supervisor, Dr. Marc Bustin for all his guidance, patience and good advice during my term at The University of British Columbia. The 5 % payoff is more than compensation for rereading my Doig papers dozens of times. Thanks also to my supervisory committee, Dr. Kurt Grimm and Dr. Lori Kennedy and my external and head, Dr. Paul Smith and Dr. Richard Chase, for their time and interest. I am indebted to all the members of the sedimentary and geochemistry research group and my office mate Stuart Knoop for listening to all my sedimentological ramblings and giving sound advice and suggestions. Access to data and core were generously provided by the Oil and Gas Commission of the Government of British Columbia, International Datashare Corporation and Shell Canada. Corporate funding was provided by Shell Canada and the Alberta Energy Company. Seismic data was generously provided by Shell Canada. I would like to thank Tom Boreen and Kelvin Colquhoun at Shell Canada and Marc Edmonds at A E C West for their time, suggestions and contributions. Special thanks to Thomas Moslow of Ulster Petroleum for so thoroughly reviewing the second chapter. Chapter 2 also benefited greatly from the work of C .G . Welsh who evaluated the seismic data donated by Shell Canada in her honour's thesis at the University of British Columbia. Research and personal funding was provided by the Natural Sciences and Engineering Council of Canada (Bustin) grant, the Thomas and Marguerite Mackay Memorial Scholarship and a scholarship provided by the American Association of Petroleum Geologists. Many thanks to the UBC geology staff and technicians for there timely support and sample preparation. Many others (too numerous to name) contributed to my research and my happiness during my stay at UBC Thank You. Finally I would like to thank an extend my deepest gratitude to my significant other, Marcy Robertson, whose tireless enthusiasm, love and spirit lent me the strength to finish this work before it finished me. CHAPTER 1 Introduction 1.1. - INTRODUCTION Recent hydrocarbon discoveries in marine sand bodies of the Triassic Doig Formation have significantly expanded oil and gas production from this interval in Northeastern British Columbia. An understanding of the factors that control the distribution and reservoir quality of Doig sand bodies is required in order to reduce the risk in further exploration. The purpose of this thesis is to provide depositional and structural models for Doig pools in northeastern British Columbia and to establish the relationship between diagenesis and reservoir quality and production for Doig pools along the entire reservoir trend in western Canada. Doig pools with core examined in this study are located in northeastern British Columbia (Fig. 1) between 94-A-13 (NW) and Township 87, Range 19 (SE) west of the 6th Meridian. The area of study extends from the Tommy Lakes field in northeastern British Columbia to the Valhalla field in west central Alberta. Since the first major discovery at Buick Creek, production from this trend in British Columbia has been approximately 20.6 x10 6 m 3 oil and 20.0 x 10 6 E 3 m 3 gas (Govt, of BC data, July, 1999). Doig reservoir rocks are clean fine-grained sub-lithic to quartz arenites and bioclastic wackestones to packstones up to 30 m thick with porosity values up to 20%. Doig pools are characterized by erratic production declines and an uneven distribution of effective porosity. The general depositional framework for the Doig Formation in the Western 1 Canada Sedimentary Basin (WCSB) has been established by previous regional studies (Gibson and Edwards, 1990, Davies, 1997). Depositional models for specific Doig pools have been examined at Wembley, Valhalla and Sinclair in Alberta (Cant, 1986 and Wittenberg, 1992) and Buick Creek in British Columbia (Munroe and Moslow, 1991, Evoy and Moslow 1995, and Evoy, 1997). No previous study documents the paragenetic history of Doig sand bodies and establishes the links between diagenesis and reservoir quality or production history of Doig reservoirs. 1.2. - STRUCTURE OF THESIS This thesis is presented as two stand-alone papers which may be read without reference to preceeding chapters. Chapter 2 investigates the depositional and structural controls of Doig Formation sand bodies in northeastern British Columbia with emphasis on the Buick Creek, Cache Creek, West Stoddart and Fireweed pools. The objectives of this chapter are to: a) document the lateral and vertical facies relationship of the sand bodies and enclosing lithologies; b) provide an environmental interpretation of facies and facies associations; c) develop a depositional model encompassing the four pools and; d) examine the role of structure in the distribution of reservoir facies. Chapter 3 investigates the link between diagenesis and reservoir quality and production history of reservoirs located along the Doig sand body trend in British Columbia and Alberta. The objectives of this chapter are to: a) document the petrology of Doig sandstones; 2 b) place diagenetic components into a paragenetic sequence; c) examine the relationship between diagenesis and reservoir quality in terms of core porosity and permeability; d) examine the relationship between diagenesis and hydrocarbon production and; e) constrain an exploration "fairway" for future Doig sand body exploration. 1.3. - REFERENCES CITED Cant, D.J., 1986. Hydrocarbon trapping in the Halfway Formation (Triassic), Wembley Field, Alberta. Bulletin of Canadian Petroleum Geology, v.34, p.329-338. Davies, G.R., 1997. The Triassic of the Western Canada Sedimentary Basin: tectonic and stratigraphic framework, paleogeography, paleoclimate and biota. Bulletin of Canadian Petroleum Geologists, v45, p.434-460. Evoy, R.W. and Moslow, T.F., 1995. Lithofacies associations and depositional environments in the Middle Triassic Doig Formation, Buick Creek Field, northeastern British Columbia. Bulletin of Canadian Petroleum Geologists, v43, p. 461-475. Evoy, R.W., 1997. Lowstand shorefaces in the Middle Triassic Doig Formation: implications for hydrocarbon exploration in the Fort St. John area, northeastern British Columbia. Bulletin of Canadian Petroleum Geologists, v45, p537-552. Gibson, D.W. and Edwards, D.E. 1990. An overview of Triassic stratigraphy and depositional environments in the Rocky Mountain Foothills and Western Interior Plains, Peace River Arch. S .C. O'Connell and J .S . Bell (eds.). Bulletin of Canadian Petroleum Geology, v.38, p. 146-158. Munroe, H.D.and Moslow, T.F., 1991. Depositional Models for the Doig Formation of northeastern British Columbia (abstract). Opportunities for the Ninties, Canadian Society of Petroleum Geologists Convention, Calgary, Alberta, Program and Abstracts, p105. Wittenberg, J . , 1992. Origin and stratigraphic significance of anomalously thick sandstone trends in the Middle Triassic Doig Formation of west-central Alberta. Unpublished M.Sc. thesis, University of Alberta, Edmonton, Alberta. 600p. Munroe, H.D.and Moslow, T.F., 1991. Depositional Models for the Doig Formation of northeastern British Columbia (abstract). Opportunities for the Ninties, Canadian Society of Petroleum Geologists Convention, Calgary, Alberta, Program and Abstracts, p105. 3 CHAPTER 2 Depositional and Structural Models for Doig Formation Sand Bodies in the Peace River Area of Northeastern British Columbia 2.1 . -ABSTRACT Middle Triassic Doig reservoirs in the Fireweed, Buick Creek, Cache Creek and West Stoddart fields (94-A-13 to Twp.86, Rge.18) of northeastern British Columbia consist of deltaic to shoreline sands encased in shelf and offshore mudstones and siltstones. The reservoirs are a series of northwest and northeast trending elongate sand bodies, up to 50 metres thick, incised into a south trending sand sheet with a maximum thickness of 15 metres. Sediments of the Doig formation are divisible into two facies associations and ten lithofacies representing deposition in shelf to offshore, and deltaic and inter-deltaic environments. Producing intervals consist of clean, very fine to fine grained, sub-lithic to quartz arenites, interbedded sandstones and both disseminated and bedded bioclastic detritus. The sedimentology and facies architecture of recent discoveries at Cache Creek and West Stoddart contrast with those identified in previous studies of Doig reservoirs at Buick Creek in northeastern British Columbia and Sinclair in west central Alberta. A three-dimensional facies model of the Doig Formation at the Cache Creek, West Stoddart and Fireweed fields depicts sandstone deposition in a deltaic environment as distributary channel fills and slumped delta front deposits. Data for the Buick Creek field 4 confirms and extends the incised shoreface model to include contemporaneous fluvial or tidal channels deposited laterally continuous with the shoreface sands. Sand bodies for all four fields were deposited contemporaneously as the Doig shoreline prograded over mudstones and siltstones of the Doig shelf. Seismic and well data reveal tectonic control on the position and orientation of the Doig reservoir trend. Syn-sedimentary growth faults control the location and geometry of thick sand bodies along the reservoir trend in the Fireweed area. 2.2. - INTRODUCTION The recent discoveries of the West Stoddart and Cache Creek hydrocarbon pools in northeastern British Columbia have significantly expanded oil and gas production from marine sandstone of the Middle Triassic Doig Formation. Doig reservoir rocks are clean fine-grained sub-lithic to quartz arenites and bioclastic wackestones to packstones up to 30 m thick with porosity values up to 20%. A general depositional framework for Doig sandstone reservoirs in the Western Canada Sedimentary Basin (WCSB) has been established by regional studies (Gibson and Edwards, 1990, Davies, 1997), and detailed studies of specific Doig pools at Wembley, Valhalla and Sinclair in Alberta (Wittenberg, 1992) and Buick Creek in British Columbia (Evoy and Moslow 1995, and Evoy, 1997). The purpose of this paper is to provide a depositional model for the Doig pools of the Fireweed, Cache Creek, West Stoddart and Buick Creek fields of northeastern British Columbia by describing the sediments, the facies architecture and the structural controls on sand body distribution. This study gives an alternative depositional model for the " 2 n d Doig sand" described by Evoy (1997) and suggests that the reservoir sandstones comprising the Buick Creek, Fireweed, Cache Creek and 5 West Stoddart fields were deposited within the same systems tract. The diagenesis and reservoir characteristics of Doig reservoirs are examined in a subsequent paper (Harris and Bustin, in prep.). The study area is located in British Columbia (Fig. 1) between 94-A-13 (NW) and Township 87, Range 19 (SE) west of the 6th Meridian. The regional trend examined in this study (Fig. 1) extends from the Tommy Lakes field in northeastern British Columbia to the Valhalla field in west central Alberta. Analyses performed in this study include the examination of 42 cores, 72 thin sections, well logs for over 300 wells, core analysis data and production data for 27 wells within the study area and 11 additional wells along depositional strike of the reservoir trend. Structural data includes 1 regional and 3 local cross-sections constructed by the author and 2d and 3d seismic data. 2.3. - GEOLOGIC SETTING The study area is located on the southwest dipping, northern flank of the "Peace River Basin" (PRB), a major structural low formed in Mississippian time (Davies, 1997). Periodic reactivation and continued subsidence of the P R B throughout the late Paleozoic and Mesozoic led to formation of a thick sedimentary succession, including over 1200 m of Triassic sediments in the western foothills of the Rocky Mountains. Triassic strata comprise a westward thickening wedge of shelf and marginal marine siliciclastics, carbonates and evaporites. These Triassic strata were deposited on what was initially believed to be the tectonically stable continental shelf of the western margin of the passive North American craton (Gibson and Barclay, 1989). Recent studies (Qi, 1995, Caplan and Moslow, 1997, Davies, 1997) suggest that 6 7 tectonism played an important role in the deposition and preservation of reservoir facies within the Triassic sequence, which is further explored in this study. The study area (Fig. 1) was located in a mid-latitudinal position, in an arid, sediment starved environment (Davies, 1997) during the Middle Triassic. Faunas are limited in Doig strata which suggests either restricted marine conditions or an enduring effect of the Permian extinction event. Hydrocarbon production in middle Triassic sediments within the study area is from shoreface and terrestrial sandstone of the Halfway, Doig and lower Charlie Lake formations which are part of a major transgressive-regressive sequence within the Triassic period (Embry, 1997). Separate nomenclature systems have been developed for Triassic rocks in outcrop (Gibson,1974,1975) and in the subsurface (Gibson and Barclay, 1989) (Fig. 2). In this study, subsurface nomenclature has been adopted with contacts between formations based on log markers and core information. Phosphatic mudstones and siltstones of the Doig Formation rest on the 2 n d order sequence boundary identified by Embry (1997) on top of Montney shelf sediments. Young (1997) gives a summary of the controversial contact between the Halfway and Doig Formations; in the majority of published descriptions the contact is considered conformable and regressive. The contact between the Doig and Halfway Formations is conformable in the study area, but becomes erosional to the east. The base of the Doig Formation is here picked at a radioactive muddy siltstone, which is a regional marker unit termed the phosphate zone (Wittenberg, 1992). Above the phosphate zone, the Doig Formation consists of a succession of mudstone, siltstone, very fine-grained sandstone, and fine-grained sandstone and bioclastic beds. 8 00/11-35-087-22W6 - SUNCOR CACHE CREEK Period/Epoch/Age GR Depth (m) Stratigraphy Sequence Stratigraphy Environment of Deposition Late Carnian H 5 2 5 ^ Upper Charlie Lake Formation 2"" SB Coplin Unconformity - 1550 -1575 Lower Charlie Lake Formation Highstand Systems Tract tidal flat evaporites, carbonates and sandtone Ladinian SSIC -1600 Halfway Formation shoreface sandstone SSIC CO T3 T3 -1625 MFS shelf/offshore siltstone/sandstone < i FS TST TRI -1650 Doig Lowstand Systems Tract 3RTSB deltaic/shoreface sandstone - 1 6 7 5 Formation Highstand Systems Tract MFS mudstone Anisian --1700 shelf/offshore phosphatic mudstone/ Phosphatic Zone TST 2MSB siltstone/sandstone Early Spathian - 1 7 2 5 - 1 7 5 0 Montney Formation Highstand Systems Tract shelf siliciclatics Fig. 2.2 - Sequence Stratigraphic framework and environments for Triassic strata within the study area (modified from Gibson and Barclay, 1989 and Gibson and Edwards, 1990). TST - transgressive systems tract, M F S - maximum flooding surface, FS -flooding surface, 2 n d/3 r c l S B - second/third order sequence boundaries. 9 2.4. - LITHOSTRATIGRAPHY AND SAND BODY GEOMETRY The Doig Formation within the study area (Fig. 2) comprises one 3 order sequence and the lower portion of another 3 r d order sequence. The lower sequence is bounded by unconformities at the base the Doig Formation (Edwards et al., 1994) and at the base of the Doig sand unit (Evoy and Moslow, 1995). The remainder of the Doig is made up of a lowstand systems tract representing reservoir sandstones and a transgressive systems tract bound at its upper extent by a flooding surface and the onset of highstand and progradation of Halfway sands. The Doig Formation comprises mudstones, siltstone and very fine-grained sandstones enclosing the fine-grained sands and bioclasts of the Doig sand bodies. Generally there is a single sandstone unit within the Doig Formation, however vertically stacked sand units separated by mudstone intervals do occur. The finer grained clastic units are interpreted as marine shelf and offshore deposits. A regression of the Doig shoreline onto the Doig shelf is interpreted to have been responsible for deposition of the sand unit. Doig sandstones are sharply overlain by siltstone, mudstone and sandstone interpreted to represent a flooding surface and a transgressive systems tract. Sediments of the Doig Formation are divided into ten lithofacies that are grouped into two facies associations (Table 1), representing shelf and offshore, and deltaic and shoreface deposits. In the following section the lithology and stratigraphy of the Doig formation is described and illustrated in sections A-A', B-B', and C-C (Figs 4,5 and 6). A summary of facies and facies associations identified in this study are provided in Table 1. Other detailed 10 Facies Assoc. Facies Description a Laminated Mudstone dark grey to black mudstone and siltstone, planar laminated, organic-rich, calcareous, rare vfg sandstone laminae, abundant fractures and pyrite, absence of body and trace fossils i b Bioclastic Mudstone dark grey to black brachiopod packstone, massive, calcareous, matrix dominantly muddy, rare silty to vfg sandstone, bioclasts are typically delicate non-abraded brachiopod plus minor pelecypod and echinoderm debris I c Laminated Siltstone dark to medium grey siltstone and vfg sandstone, planar to wavy laminated, cm scale convolute inter-bedded vfg sandstone, calcareous, abundant cut-and-fill structures, rare Hz traces, scattered echinoderm and brachiopod debris a Muddy Sandstone light grey vfg quartz sandstone and mudstone, ripple laminated to x-bedded, abundant cut-and-fill structures, load casts, mudstone rip-ups, calcareous, moderately abundant horizontal traces, synaeresis cracks, rare bivalve fossils b Massive Sandstone brown to light grey vfg-fg quartz sandstone, massive, moderately sorted, sub-angular, calcareous, abundant mudstone rip-ups, calcite cements visible as concretions, traces absent, rare abraded bioclastic debris c Laminated Sandstone brown to light grey vfg-fg quartz sandstone, low to high angle laminated to x-laminated, H C S , moderately sorted, subangular, calcareous, abundant mudstone rip-ups, calcite cements visible as concretions or in zones following primary structure, rare bioclastic debris and traces. 2I,II d Bioclastic Sandstone light grey vfg-fg quartz sandstone as above with 20-30% coarse sand to pebble sized abraded bioclastic debris, massive to planar laminated, abundant visible intergranular calcite, rare vuggy porosity, traces absent e Interbedded Sandstone/Coquina brown to light grey vfg-fg quartz sandstone as in 2c interbedded with pelecypod coquina, abraded bioclasts, abundant lithic clasts and mudstone rip-ups, abundant visible calcite appears related to bioclastic material, coquina can appear as isolated lenses or breccia clasts in a sandstone matrix, rare traces f Coquina light grey coquina, 60-90% abraded bivalve bioclasts in a fg quartz sandstone matrix, x-bedded (normal and inverse), moderately to poorly sorted, bioclasts moderately imbricate, abundant mudstone rip-ups, visible intergranular calcite, traces absent g Mudstone Breccia Granule to pebble breccia, mudstone clasts in a vfg -fg quartz sandstone matrix, imbricate, rounded to angular clasts, poorly sorted, mudstone, semi-lithified deformation structures, rare bioclastic debris, traces absent Table 2.1 - Facies Descriptions stratigraphic sections and facies descriptions for the Doig Formation can be found in Wittenberg (1992), Evoy and Moslow (1995) and Evoy, (1997). 2.4.1. - FACIES AND FACIES ASSOCIATIONS Sediments of association 1 are composed of fine-grained mudstone, siltstone and very fine-grained sandstone that act as both seals and source rocks to the reservoirs of association 2. Facies association 2 consists of very fine-grained to fine-grained quartz sandstone, coquina and mudstone. Facies association 2 can be further sub-divided into associations 2i and 2ii based on vertical lithofacies stacking. Facies association 2i (Fig. 3b) is a coarsening upward package of fine-grained sandstone and mudstone facies which erosively overlie and underlie the sediments of association 1. Facies association 2ii (Fig. 3a) is a massive to fining upward package of fine-grained sandstone, coquina and bioclastic sandstone facies erosively overlying association 1. At Buick Creek, associations 2i and 2ii are laterally equivalent. Previous interpretations by Evoy and Moslow (1995) placed deposition of association 1 in a distal to proximal shelf environment and association 2 in an offshore to upper shoreface environment. Interpretations from this study are in agreement but expand association 2 to include deltaic deposits. 12 a ) WEST STODDART - 14-31 -87-21W6 Depth(m) G R LOG 1615 1625 LITHOLOGY 1635 1645 1655 1665 not cored A A A A A A * • •. ••) • & ' ' . . e> • ' .CP/ •J . c? . • • i> '?' • \ <p • '. cP • • & • •<?.' .• . *. FACIES A S S O C I A T I O N 1 Offshore/Shelf Clastics (facies 1a, 1c) A S S O C I A T I O N 2ii Distributary Channel Fill (facies 2c, 2e 2f,2g) A S S O C I A T I O N 1 Shelf Clastics facies (1a, 1c) \>l Facies 2f fc<K 'f-j:';) Facies 2e Facies 2b, 2c,2g Facies 1c Facies 1 a sharp contact b) BUICK CREEK - B-77 I/94-A-11/2 Depth(m) G R L O G LITHOLOGY FACIES 1370 1380 1390 1400 1410 A,pl (Abrupt, high angle, A ' slumped contact A S S O C I A T I O N 1 Shelf/Offshore Clastics (facies 1a, 1c) A S S O C I A T I O N 2i Middle/Upper ShorefaceTransition (facies 2a, 2b 2c,2e) A S S O C I A T I O N 1 Shelf Clastics (facies 1a, 1b, 1c) A Apl missing core Facies 2b, 2c,2g Facies 2a Facies 1c Facies 1a sharp contact sharp contact, pebble lag Fig. 2.3 - Facies associations within the Doig Formation: a) at West Stoddart, b) at Buick Creek 13 2.4.2. - C R O S S - S E C T I O N S AND FACIES ARCHITECTURE Wireline logs and cores permit reconstruction of the depositional history and architecture of the Buick Creek, Fireweed, Cache Creek and West Stoddart reservoirs. Sandstone, mudstone and bioclastic intervals are picked using a combination of gamma and photoelectric logs. Local and regional stratigraphic sections are constructed on the upper phosphatic marker of the Doig Formation in order to depict facies relationships at the time of deposition. The upper phosphatic marker is picked on gamma logs at the last significant radioactive spike that records the presence of phosphatic material in lower Doig sediments. The abrupt reduction in phosphatic material above this marker is interpreted as a regional shift in oceanographic circulation or a cessation of condensation (Glenn et al., 1994) and is therefore a regional marker horizon within the Doig Formation. Markers above the datum, picked using lithologic breaks in core and gamma logs, are correlated laterally to define stratigraphy. 2.4.2.1. - West Stoddart and Cache Creek The geometry of the Doig sandstone unit at West Stoddart and Cache Creek is illustrated by a west-east cross-section (Fig. 4, line AA') constructed across the regional Doig shoreline trend of Evoy and Moslow (1995). Upper Doig, Halfway and lower Charlie Lake strata are tilted and thin to the East. Sandstones within the Doig comprise a lobate "sand sheet" 3 - 5 m thick, locally incised by six elongate sand bodies 1 5 - 3 0 m thick, 2 - 4 km wide and 1 - 7 km long (Fig. 7). The "sand sheet", cored at 10-36 (Fig. 4), rests conformably upon laminated mudstones of Facies 1a (Fig. 8a) and coarsens upward through laminated mudstone and sandstone of Facies 2a (Fig. 8c) and 14 Fig. 2.4 - Section A-A' through West Stoddart field oriented parallel to depositional dip. Datum is the upper Doig phosphatic marker, cored intervals are shown. Note structural inversion of graben due to position of datum. Cross-section orientation and location are shown in Fig. 2 . 1 . Fig. 2.5 - Section B-B' through Fireweed, Cache Creek and West Stoddart fields, oriented perpendicular to depositional dip. Datum is the Doig upper phosphatic marker, cored intervals are shown. Cross-section orientation and location are shown in Fig. 2.1. 15 massive sandstone of Facies2b (Fig. 8a). Facies 2b sandstone is truncated westward and eastward by thick channel deposits of laminated sandstone and coquina of Facies 2c, 2e, 2f and 2g (Fig. 9) which sharply overlie laminated mudstone and siltstone of Facies 1a and 1c (Fig. 8b). The contact cored at 4-03, has no structures or lag indicative of erosion or transport. Gamma ray logs for the "channel-like" deposits have a blocky signature, or a cleaning-upward signature as in cores 4-03 and 1-05. The inter-bedded sandstone and coquina facies within the deposits are truncated to the southwest and northeast by finer grained mudstone and sandstone of the "sand sheet" deposit. Sections AA' and DD' illustrate that the two large channels comprising the Doig pools at the West Stoddart and the Cache Creek fields are structurally offset. The abrupt truncation of channel facies between the reservoirs in favor of the sand sheet facies at this offset is coincidental and not structurally controlled. A small northwest-southwest trending fault bounded graben between the two channels (Fig. 4) formed during Charlie Lake time and structurally separates the Cache Creek and West Stoddart reservoirs. 2.4.2.2. - Fireweed The geometry of the Doig sandstone at Fireweed is illustrated by a north-south cross section (Fig. 5, line BB') constructed parallel to the interpreted shoreline trend. The Charlie Lake, Halfway and Doig markers are generally parallel to the upper phosphate datum with some offset as a consequence of differential compaction. The net sandstone isopach (Fig. 7) at Fireweed illustrates an irregular lobate sand body, elongate NE-SW, 5-15 m thick with isolated sand 'pods' 30 - 50 metres thick along the 16 0 5 km Doig sandstone j S £ transgressive suface of erosion PL pebble lag unconformity core coarsening up d-31-H c-82-A a-74-A c-45-A d-35-A d-6-A d-76-l 2/d-57-l 9-34 14-32 25m 00m 75m-50m-25m Om Phosphatic Matter Montney -^ Fig. 2.6 - Section C-C through Buick Creek field oriented perpendicular to depositional dip. Datum is the Doig upper phosphatic marker, Charlie Lake markers are included to highlight stratigraphic relationships, cored intervals are shown. Cross-section orientation and location is shown in Figure 1 Fig. 2.7 - Total Doig sand isopach within the study area 17 Fig. 2.8 - (a) Facies 1a, Laminated black mudstone sharply overlain by Facies 2b, quartz sandstone (04 03 088 22W6,1704.6m). (b) Facies 1c, siltstone interlaminated with vfg quartz sandstone (b-77-l/94-A-11/2,1405m). (c) Facies 2a, muddy sandstone, vfg-fg quartz sandstone with wavy mudstone laminae and soft sediment deformation features (12 35 087 22W6, 1662.3m). F ig . 2.9 - (a) Facies 2c, laminated vfg quartz sandstone, low angle planar laminae, intergranular <$> = 18.0% (d-68-l/94-A-11,1398.8m). (b) Facies 2e, interbedded fg quartz sandstone and bivalve coquina, faulted, abundant calcite cement, intergranular and moldic porosity (14 31 087 21W6, 1635.5m). (c) Facies 2f, bivalve packstone, vfg-fg quartz sandstone matrix, highly abraded and recrystallized, abundant moldic/vuggy porosity (15 21 087 20W6, 1561.2m). 18 down dip edge of the deposit. Gamma ray logs exhibit a heterogeneous array of sand bodies within the Fireweed area, making correlation of the Doig sand unit along section BB' problematic. The sandstones cored at b-26-D and b-6-D (Fig. 5) have abrupt contacts with underlying mudstone and siltstone of Facies 1a and 1c, and contain abundant pyrite, microfractures and convolute laminae. Cored wells in the Fireweed field exhibit either a massive package of inter-bedded coquina and quartz arenite or coarsening up successions of mudstone, sandstone and coquina. Sand bodies cored at b-26-D and b-6-D resemble the thick channel-shaped sand bodies described earlier in this study from the West Stoddart and Cache Creek fields. The thick sand body cored at d-42-H is approximately 40 m thick and is isolated (Fig. 7), controlled by a growth fault interpreted from stratigraphy (Fig. 5) and seismic data (Fig. 17). The sand body at c-80-L is a massive bioclastic conglomerate with abundant whole and fragmented brachiopod and bivalve clasts in a matrix of very fine-grained sandstone to siltstone. Gamma logs for the other non-cored wells in this section suggest that sandstone intervals are comprised of conformable, coarsening up successions of mudstone and quartz arenite similar to those described for Section AA'. The abrupt lateral facies shift and offset in the 11-10 well is the northwest extension of the graben trend in AA' and DD' between the Cache Creek and West Stoddart fields. 2.4.2.3. - Buick Creek The geometry of the Doig sandstone unit at Buick Creek is illustrated by a north-south cross section (Fig. 6, line C C ) constructed parallel to the interpreted shoreline trend. Charlie Lake, Halfway and Doig markers and contacts are parallel and are offset between wells. Sandstones within the Doig Formation are continuous, elongate north-19 south, 20 - 40 m thick, 16 km long and 2-3 km wide. Two depositional facies associations are defined within core (2i, 2ii) based on lithology and textural variations. The first association (2i) occurs at 09-34 which coarsens upward with well defined composite bedsets of laminated sandstone and mudstone of Facies 2a grading upward into massive to laminated sandstone and coquina of Facies 2b, 2c and 2e. The uppermost sandstone at 09-34 has a uniform grain size distribution and a blocky log character. The second facies association (2ii) occurs at C N R L Buick d-6-A, where laminated sandstone and mudstone breccia of Facies 2c and 2g sharply overly Facies 1a mudstones on a slumped, and pyritized contact. The sandstones of association 2ii have uniform lithology and lack textural variation and hence have a blocky gamma ray log signature. The lower contact was not cored but is sharp on the gamma ray log. Facies association 1 grades upward into association 2 or is laterally equivalent to association 2 in adjacent wells. Fine-grained arenites of Facies 2b and 2c at d-6-A and d-35-A are capped by a pebble lag overlain by siltstone and very fine-grained arenites of Facies 1c. At d-76-l, laminated mudstone and sandstone, and inter-bedded sandstone and coquina of Facies 2a and 2e are overlain by a succession of mudstone, very fine-grained sandstone and mudstone breccia capped by a pebble conglomerate followed by siltstone and very fine-grained sandstone of Facies 1c. Transverse sections of the Buick Creek deposit (not shown here) show both a thickening and coarsening of the sand body from west to east. The coquina Facies 2f occurs in Buick core in the southern portion of the Buick Creek field. The sandstones of the Buick Creek reservoir are erosionaly truncated by Halfway sands to the North at d-31-H and grade into Facies 1a mudstone to the South. 20 2.5. - DEPOSITIONAL SETTING The mode of deposition of sand bodies within the Doig Formation is both controversial and complex. Previous interpretations involve a wide spectrum of environments and mechanisms of transport. Munroe and Moslow (1991) interpret Doig sand bodies in northeastern British Columbia as sediment gravity flows, in contrast with Evoy and Moslow's (1995) interpretation of the same deposits as incised lowstand shorefaces. Interpretations of similar sandstones to the southeast of the study area include estuarine channel fill (Cant, 1986), deltaic inner fringe sands (Styan and Shaw, 1991) and shoreface sourced mass wasting deposits (Wittenberg, 1992). A new depositional model is proposed here based on data from the Fireweed, Cache Creek and West Stoddart fields, and incorporating data from Buick Creek, Rigel, Tommy Lakes, Two Rivers, Kilkerran, Ft. St. John, Groundbirch and Scott fields to provide a regional perspective. The position of Doig sandstones abruptly overlying shelf mudstone and siltstone facies suggests either the presence of an unconformity or extensive transport. The geometry of the sand bodies and physical structures noted in the core contradict the latter interpretation. 2.5.1. - INTERPRETATION OF FACIES AND FACIES ASSOCIATIONS Association 1 (Facies 1a, 1b and 1c) represents mudstone and siltstone deposition in a restricted marine shelf environment, below storm wave base. Recurrent lenses of very fine-grained sandstone and siltstone indicate periodic high-energy events such as storms or mass flows. Abundant organic carbon, collophane, pyrite and restricted body 21 and trace fossil assemblages all indicate euxinic bottom water conditions during deposition (Gibson and Edwards, 1990, and Wittenberg, 1992). The lateral continuity of facies in association 1 (Fig. 16, Gibson and Edwards, 1990) throughout the W C S B indicates a large-scale depositional setting such as a marine shelf in contrast to smaller-scale restricted environments such as lagoons or shallow protected bays. Interbeds of Facies 1c are sharp based and deposited as a random mixture of non-oriented, delicate whole and fragmented bioclasts in a muddy very fine-grained sandstone matrix. Facies 1c interbeds are interpreted as event deposits of periodic storms, transporting brachiopod, echinoderm and bivalve debris onto the Triassic shelf. Association 2 mudstones and sandstones (Facies 2a - 2f) are interpreted to have been deposited in a marine shoreface environment (Walker and Plint, 1992) above storm wave base. Facies 2a is composed of cross-bedded and wavy laminated sandstone and mudstone with a low to moderate diversity of horizontal traces consistent with delta front (Bhattacharya and Walker, 1992) or transition-lower shoreface (Walker and Plint, 1992) environments. Facies 2a generally coarsens upward as traction currents supplied increasing amounts of coarse sediments during regression of the shoreface. Facies 2a is unique in association 2 for its relative abundance of the traces Planolites, Teichichnus, Palaeophycus and escape traces. The trace fossils represent a Cruziana assemblage, characteristic of quiet to moderate energy conditions in a sub-tidal marine environment (Pemberton et al., 1992), periodically punctuated by high-energy depositional events generating an abundance of escape structures. Abundant synaeresis cracks probably represent fluctuating salinity conditions (Plummer and Gostin, 1981) reflecting fluvial input or alternatively, syn-sedimentary tectonic movement and dewatering (Pratt, 1998) caused by loading of overlying sediments. 22 Facies 2b and 2c are composed of laminated to massive very fine to fine grained quartz arenites deposited in a current dominated environment. Facies 2b and 2c sandstone is interpreted as amalgamated channel fills, at West Stoddart, Cache Creek, and as middle-upper shoreface/delta deposits at Buick Creek and Fireweed. The channel fill sandstones comprise repetitive fining upward beds of cross-laminated sandstones and coquina with abrupt lower contacts but showing no evidence of extensive erosion or transport. Shoreface and delta front sandstones were deposited as coarsening up successions of muddy to clean sandstones of Facies 2a, 2b and 2c. A transition from wavy laminated muddy sandstone to cross-laminated clean sandstone indicates increased flow velocities as the shoreface prograded. Sparse Ophiomorpha (Fig. 10b) and vertical escape traces reflect a near-shore or shoreline marine environment associated with shifting substrates and continuous wave energy (Frey and Pemberton, 1985). The appearance of trough cross-stratification with mud draped foresets (Fig. 10d) indicates a strong tidal influence (Singh & Singh, 1992) in Facies 2c. Facies 2f, composed of highly abraded bivalve clasts and quartz sandstone, was deposited as beds and lenses in a high-energy shallow marine environment similar to Facies 2b and 2c. Bioclastic accumulations form sharp based coquina beds, generally fining upwards with a variable abundance of quartz sand matrix, grading into Facies 2d. Fractures, mold fills, karst (Fig. 10a) and boring structures indicate both early submarine lithification and sub-aerial exposure. The monospecific nature of the shell beds and the high degree of abrasion (Fig. 9c) suggest accumulation in a shallow, salinity stressed environment. Shell concentrations are extensively reworked in a storm and wave dominated setting forming shoal and beach ridge deposits that are lithified 23 Fig. 2.10 - (a) karst features in sandstone and bioclastic facies (d-46-l/94-A11,1366m). (b) Ophiomorpha (Op) traces in facies 2a sandstone(01 05 88 21W6,1662m). (c) Facies 2g, mudclast breccia, cross-stratified sandstone containing mudstone rip-ups (01 05 88 21W6,1657m). (d) mud draped forsets on trough cross-stratified facies 2c sandstone (b-64-l/94-A-12/2, 1697m). 24 early and periodically exposed. Similar accumulations of bivalves are found in modern settings associated with shallow, salinity stressed environments (Logan and Cebulski, 1970, Salazar-Jiminez et al., 1982). Mudstone breccias of Facies 2g (Fig. 10c) are deposits of high energy storm events within the shoreface/deltaic environment associated with Facies Association 2. Breccia clasts are elongate angular mudstone chips deposited with cross-stratified sandstone of Facies 2c in intervals varying in thickness from centimetres to metres. In several cores, the breccia grades into a massive mudstone as matrix sandstone becomes increasingly sparse. A similar lithofacies described as desiccated mud chips from exposed muddy banks or tidal flats was noted in channel fill complexes of the Viking formation of central Alberta (MacEachern and Pemberton, 1994). Semi-lithified mud chips may be periodically ripped up and intermixed and transported with sands by storm events, short distances in an offshore direction. 2.5.2. - DEPOSITIONAL MODELS FOR SAND BODIES COMPRISING THE FIREWEED, C A C H E C R E E K , W E S T STODDART AND BUICK C R E E K P O O L S A lack of outcrop, sparse core coverage and the highly variable nature of the Doig sand unit precludes constraining of the depositional model to a single environment. A number of environments including tidal inlet deposits, shelf sheet sands, delta and shoreface deposits were considered in an attempt to account for all the characteristics of Doig sand bodies within the study area. The interpretation that best fits the sandstones comprising the Fireweed, Cache Creek and West Stoddart pools is a wave and tide influenced delta complex as illustrated in Figure 11. The sandstones 25 Fig. 2.11 - Sedimentological model for the Doig Formation at West Stoddart, Cache Creek and Fireweed fields, northeastern British Columbia. The diagram has extreme vertical exaggeration. 26 comprising the Buick Creek pools are interpreted as an incised shoreface, complimenting and extending Evoy and Moslow (1995) interpretation to include depositional mechanisms. The following section provides evidence in support of our interpretation and a brief description of other models considered as possible alternatives. The presence of wavy to planar cross-beds, Ophiomorpha traces (Fig. 10b), angular mudstone rip-ups (Fig. 10c) and evidence of karst (Fig. 10a) and early lithification in Facies Association 2, indicate a shallow, high energy marine environment above fair weather wave-base in a sub- to inter-tidal setting. A mixed regime of tidal and wave energy is interpreted from the abundant and highly abraded bioclastic beds, the abundant cross-stratification and rhythmically laminated sandstones and mudstones. The distribution of the sandstone within the Doig reveals a northwest-southeast trend of bulls-eyes and channel shaped sand bodies (Fig. 7) oriented along strike of the paleo-shoreline interpreted by Evoy and Moslow (1995). Stratigraphic sections perpendicular to the long axis of the channel sands at West Stoddart and Cache Creek show that the channels are deeply incised into underlying shelf mudstones (Fig. 4) and are laterally adjacent to thin, normally graded sheet sandstone. Emplacement of the nearshore sands and bioclastic debris onto shelf mudstones is attributed to relative fall in sea level, exposing shelf sediments to fluvial erosion followed by a period of rising sea level that allowed the development of a lowstand-to-transgressive wedge. Pebble to cobble lags overlying the sandstone in Buick Creek core are interpreted as transgressive surfaces of erosion. Above the transgressive surface are shelf to offshore mudstones and siltstones of Facies Association 1. A similar transgressive surface is proposed at West Stoddart, Cache Creek and Fireweed at the upper contact of the Doig sandstones 27 (Fig. 4). Available dipmeter logs from Buick Creek and Cache Creek (Fig. 12) show bedding dips preferentially oriented sub-parallel to the paleo-shoreline trend. Shore parallel deposition suggests that long shore currents were the primary depositional mechanism at Buick Creek and that distributary channels were oriented sub-parallel to the paleo-shoreline at Cache Creek. Normal faults that are isolated to middle Triassic strata along the down-dip edge of the sand deposit at Fireweed (identified subsequently) are interpreted as syn-sedimentary growth faults. Seaward dipping growth faults have been identified in modern and ancient examples as a control on the morphology of a prograding lowstand delta system (Bhattacharya and Walker, 1992). The Doig sandstone at West Stoddart and Cache Creek are amalgamated distributary channel fill sand bodies. Similar sand bodies are described by Meckel (1975) for the Holocene delta system of the Colorado River. In the Colorado River, channel-fill sand bodies are 25-30 m thick, consisting of dip-oriented, multiple, superimposed upward fining depositional units composed of cross-stratified well sorted sands, abundant mud drapes and shelly debris. The orientation of Doig channels oblique to and along strike of the shoreline trend can be attributed to underlying structure (Ashley, 1994) which can control the fluvial drainage pattern on the coastal plain. The coarsening up 'sheet-like' sandstones at West Stoddart and Cache Creek are interpreted as reworked delta front, barrier and channel mouth bar deposits. The source of the bioclastic material was monospecific populations of bivalves and brachiopods inhabiting the salinity stressed tidal flats and lagoons of the Doig shoreline. Shell material was reworked by storm and wave energy into cheniers and beach ridges similar to those found in Pleistocene sediments of the northern Gulf of California (Meldahl, 1995). In contrast to modern and ancient delta systems (Fisher et al., 1969, Frazier, 1967), the core examined in this 28 3k Suncor Cache 12-35-87-22W6 Tadpole (deg) Depth(m) GR (API) 9 0 O . O O 1 5 0 . 0 0 ^ 1 6 9 0 Fig. 2.12 - Dipmeter log through interpreted channel sandstones of the Cache Creek field. Tadpoles show dip direction and angle of sedimentary beds. Note consistent dip direction to the North in the interpreted channel fill, parallel to the paleo-shoreline trend. study contain no evidence of terrestrial depositional facies. It is likely that the transgressive surface in Buick Creek cores represented an erosive event that reworked/removed terrestrial facies overlying the marine deposits of the delta complex. The thick sand bodies at Fireweed are interpreted as a product of slumping and rapid subsidence along growth faults caused by progradation of the delta complex over unstable pro-delta-slope muds along a shelf margin (Edwards, 1981). This interpretation is supported by the presence of syn-sedimentary growth faults identified in the seismic data (described in a following section) along the down dip edge of the interpreted delta front. Other thick sandstones in the Fireweed area include distributary 29 fill, overbank splays, bay-mouth bars and delta front sands associated with the delta complex. The main sand body at Buick Creek is interpreted as an incised shoreface deposit. Similar sharp-based elongate sand bodies are described by Plint (1988) within the Cardium Formation of Alberta. Sand bodies of the Cardium Formation were deposited as lowstand shorefaces, erosively overlying fine-grained shelf sediments. The resultant sand bodies are up to 20 m thick and elongate parallel to the inferred Cardium shoreline trend. Internally, the sand bodies coarsen upward from bioturbated mudstone to inter-bedded hummocky cross-stratified sandstone and bioturbated mudstone, capped by a gravelly transgressive lag (Walker and Plint, 1992). Like the Cardium sand bodies, the coarsening upward facies succession at Buick Creek is interpreted as a prograding shoreface incised onto muddy shelf sediments during a forced regression (Plint, 1991). The coarsening-up shoreface sandstones can be traced laterally to massive sandstones (well d-6-A, Fig. 5) which represent fluvial or tidal channels incised into the shoreface or underlying shelf mudstone. There is no evidence to suggest the Buick Creek sandstones were deposited as a separate event to the deltaic deposits of the Fireweed and Cache Creek fields as suggested by Evoy (1997). The distribution and correlation of the sand bodies (Fig. 7) reflects contemporaneous deposition within a combination of deltaic and inter-deltaic environments. The orientation of the sand bodies both parallel and oblique to the interpreted Doig paleo-shoreline reflects the complexities possible in a paralic environment as witnessed on modern shorelines such as Shark Bay on the western coast of Australia (Logan and Cebulski, 1970). 30 2.5.3. - ALTERNATIVE DEPOSITIONAL ENVIRONMENTS The deposition of isolated sand bodies encased in mudstone and siltstone could be accomplished by other mechanisms. In the course of this study, two other depositional environments were considered as possible origins for the sand bodies at West Stoddart, Cache Creek and Fireweed and were subsequently discarded. 2.5.3.1. - Tidal inlets/barrier islands Accreting tidal inlets/barriers could produce thick channels oriented parallel to the paleo-shoreline similar to those described at Cache Creek and West Stoddart. Modern barrier/lagoon environments and facies models have been extensively studied and reviewed by Davis (1994) and Reinson (1995). Doig sandbodies in this study have stratification dipping parallel to the paleo-shoreline, a lack of lag deposits at the base of the channel fill and an absence of well developed cross-stratification, all contrary to accepted evidence for identifying tidal inlet environments. 2.5.3.2. - Shelf sheet sands incised by tidal/storm channels The geometry of sheet-like sandstones encasing marine mudstones and siltstones at Fireweed, Cache Creek and West Stoddart fields suggests a possible origin for Doig sands as shelf deposits. In this scenario, sandstones are deposited as migrating sandwaves, tidal ridges and storm surge channels onto shelf mudstones. Shelf sandstones have been documented for modern (Swift and Thome, 1991) and ancient deposits (Brenner and Davis, 1974). Doig sandbodies in this study have karst-like 31 structures, deep incised channels a lack of clearly defined hummocky cross-stratification and a sandstone geometry, all contrary to accepted evidence for identifying deposits from a shelf environment. 2.6. - STRUCTURAL CONTROLS ON RESERVOIR DISTRIBUTION 2.6.1. - REGIONAL CONSIDERATIONS The study area is situated on the northern flank of the Dawson Creek Graben Complex (DCGC; Barclay, 1990), just south of the Permian Beatton High (Fig. 13). The D C G C was formed in an episode of extension and uplift during the early Carboniferous and underwent periodic reactivation and subsidence through the Paleozoic and Mesozoic (O'Connel et al., 1990). Both O'Connel (1990) and Davies (1997) suggest that reactivation of faults within the D C G C influenced both Triassic and post-Triassic deposition and hydrocarbon trapping. Figure 13 illustrates the location of the D C G C and other tectonic elements that may have influenced sedimentation during or after the deposition of the Doig Formation. Structural sections and seismic data were examined to assess the origin and influence of structure on both the position of the reservoir trend of Doig sands and the distribution of locally thick sand bodies along the reservoir trend. A structure map built on the upper phosphatic marker of the Doig Formation (Fig. 14) illustrates a southwesterly regional dip and a prominent north-south structural trend. 32 Fig. 2.13 - Structural elements intersecting the regional Doig sand trend (shaded) in the Western Canada Sedimentary Basin. Modified from compilation by Davies (1997). 33 R24 R23 R22 R21 R20 R19 Fig. 2.14 - Structure contour map of the top of the Doig Formation upper phosphatic marker. There is a southwesterly regional dip and several prominent north-south linear structural features including the graben separating the Cache Creek and West Stoddart fields. Contour Interval = 20 m. 34 2.6.2. - DEPOSITION OF DOIG S A N D S AT S T R U C T U R A L L Y C O N T R O L L E D SHELF B R E A K S Reactivation of Peace River Arch structures has been suggested as a possible mechanism controlling the deposition of Doig sandstone reservoirs (Cant, 1986, Qi, 1995). Qi (1995) interpreted listric normal faults from 2D seismic lines, extending from pre-Cambrian to Devonian strata that underlie Doig seismic anomalies. Interpreted reactivation of these structures (Qi, 1995) was associated with paleo-slope breaks on a marine shelf, which localized the position of the Doig shoreface interpreted by Evoy and Moslow (1995). Two-dimensional seismic lines in the Fireweed area show numerous reverse faults and folds underlying the Doig reservoir trend (not shown). The reverse faults originate below and terminate in the Mississippian section, whereas the related folds propagate up through to the Cretaceous - suggesting a Laramide origin. It is possible that these structures existed as normal faults prior to the Jurassic and were subsequently inverted, but there is no supportive evidence. The abrupt thickening of the upper Doig formation isopach (Fig. 15) shows the position of a possible paleo-slope break which may have been controlled by normal fault structures, created during a period of Mississippian extension of the Peace River Arch structure. The thickness trend coincides with the location of the Fireweed and Cache Creek reservoir trends. 2.6.3. - S T R U C T U R A L F E A T U R E S F R O M LOG DATA Cross-section D-D' constructed perpendicular to the reservoir trend (Fig. 16) shows distinct offsets in Middle Triassic strata in relation to Late Triassic markers which are continuous and dip gently to the southwest. Middle Late Triassic offset is interpreted as 35 break Fig. 2.15 - Doig Formation isopach within the study area, from the upper phosphatic marker to the base of the Halfway Formation. Interpreted paleo-slope break and paleo-shoreline are shown along with location of stratigraphic section D-D'. 36 a product of tectonic movement along normal faults, possibly coeval with the creation of the Coplin unconformity (Embry and Gibson, 1995), a 2nd order sequence boundary separating sediments of the lower and upper Charlie Lake Formation. Movement along faults may have occurred both during and after the deposition of the Doig sandstone, affecting both the deposition and later trap formation of the reservoir unit. The cross-cutting fault structures may act as effective up-dip seals for Doig reservoirs. Cross-sections constructed parallel to regional dip (not shown) reveals a westward thickening of the Triassic section between the Doig upper phosphatic marker and the Nordegg marker and no corresponding thickening of the Doig phosphate zone. Units immediately above the Nordegg marker show little thickness change across the section. Therefore, significant tectonic uplift and tilting is interpreted to have occurred subsequent to the deposition of the phosphate zone and prior to deposition of Jurassic sediments. 2.6.4. - SYN-SEDIMENTARY GROWTH FAULTING Reservoirs in the Doig formation are locally thick, elongate sandstone or sandstone and coquina bodies parallel to the interpreted paleo-shoreline (Evoy and Moslow , 1995). Cant (1986), and Wittenberg (1992) both suggest tectonic structural movement as a control on Doig sand body deposition in west central Alberta. Evoy and Moslow (1995) interpreted accumulations of Doig sandstone in northeastern British Columbia resulting from sea level fluctuations on a low relief marine shelf with little structural modification. In this study, 2D and 3D seismic data shot over the Fireweed area were examined in combination with core and log data in order to assess the influence of structure as a 38 Fig. 2.17 - 3D seismic line showing middle Triassic growth fault at down-dip edge of the Fireweed delta complex. Profile is oriented perpendicular to interpreted shoreline trend, Location is confidential. syn-sedimentary control on accumulation of thick reservoir sand bodies. Seismic data reveals the presence of small normal faults coincident with sandstone accumulations (Fig. 17). The faults are constrained to the Middle Triassic and are interpreted as syn-sedimentary growth faults caused by the accumulation of clastic material along the down-dip edge of the delta complex. Slumping along this front provided the accommodation space required to produce locally thick, isolated sand bodies. In contrast, our examination of Cache Creek and West Stoddart core reveals no evidence that structure played a significant depositional role. The fault bounded graben, identified in section AA' (Fig. 4) between the Cache Creek and West Stoddart fields, indicates that structural movement during the Late Triassic may have isolated these two sand bodies. The appearance in core of high angle contacts, over-steepened bedding and fault offsets in cores of all fields indicates that some slumping and 3 9 sediment gravity flow did occur during Doig time. Such structures appear intermittently both within individual core and from core to core, and appear to have no overall relationship to the fault structures identified from seismic and well data. A representation of the regional and local structural control on Doig sand bodies is illustrated with an isopach of the study area (Fig. 15). The isopach map illustrates the position of the Doig shoreface trend at Fireweed, Cache Creek and West Stoddart controlled by an interpreted underlying paleo-slope break. Control of the slope break by underlying faults is postulated but cannot be demonstrated from the data. Slumping and accumulation of deltaic sandstones on syn-sedimentary growth faults is interpreted to control the occurrence of locally thick sand bodies at Fireweed along the shoreline trend. Resedimentation of deltaic sediments as slumps and mass flows is widely recognizeded (Edwards, 1981, and Mayall et al. 1992) and confirms this mechanism of Doig sand deposition recognized by Wittenberg (1992) in west central Alberta. 2.7. - SUMMARY AND CONCLUSIONS Thick sand bodies of the Doig Formation in northeastern British Columbia are deltaic and inter-deltaic shallow marine sands deposited during a regression of the Doig shoreface into the study area. The position of the Doig shoreface was controlled by a paleo-slope break related to underlying Mississippian-aged normal faults. Locally, thick sand bodies deposited along the Doig shoreface were controlled by accommodation created by slumping along syn-sedimentary normal faults. Specific conclusions reached in this study are as follow: 40 1) Sandstones within the Middle Triassic Doig Formation in northeastern British Columbia form broad sheet deposits up to 15 metres thick, incised by channel-shaped sand bodies oriented roughly parallel to interpreted paleo-shoreline. 2) Doig channel-shaped sand bodies at the West Stoddart and Cache Creek fields were deposited as amalgamated distributary channel fills in a deltaic setting. 3) Locally thickened sandbodies in the Fireweed field were a product of slumping and rapid subsidence along seaward dipping syn-sedimentary growth faults during the progradation of deltaic sands over unstable pro-delta and shelf mudstones. 4) Evoy and Moslow's (1995) and Evoy's (1997) interpretation of the Buick Creek sand body as an incised shoreface deposit is confirmed and extended to include tidal and fluvial channel fills deposited within the same systems tract and laterally continuous with shoreface sands. 5) Data from this study suggest a contemporaneous origin for the sand bodies at Buick Creek, West Stoddart, Cache Creek and Fireweed. No evidence was found to indicate that these reservoirs were deposited as separate events as suggested by Evoy (1997). 6) Isopach and structural sections across the study area reveal tectonic control of the Doig reservoir trend, but evidence from 2D seismic data is obscured by Laramide reactivation of deeper fault structures. 41 7) Structural sections across the study area indicate significant tectonic movement constrained to the Charlie Lake Formation, structurally isolating Doig pools along the reservoir trend. 2.8. - REFERENCES CITED Ashley, G.M. , and Sheridan, R.E., 1994. Depositional model for valley fills on a passive continental margin, jn R.W. Dalrymple, R. Boyd and B.A. Zaitland, edits. Incised-Valley Systems: Origin and Sedimentary Sequences, S E P M special publication No. 51, p285-301. Barclay, J .E , Krause, F.F., Campbell, R.L, Utting, J . , 1990. 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Deltas. Houston Geological Society, p87-98. Meldahl, K.H., 1995. Pleistocene shoreline ridges from tide-dominated and wave-dominated coasts: northern Gulf of California and western Baja California, Mexico. Marine Geology v123, p61-72. Moslow, T.F. and Tye, R.S., 1985. Recognition and characterization of Holocene tidal inlet sequences (North Carolina, South Carolina). Marine Geology, v63, p129-151. Munroe, H.D.and Moslow, T.F., 1991. Depositional Models for the Doig Formation of northeastern British Columbia (abstract). Opportunities for the Ninties, Canadian Society of Petroleum Geologists Convention, Calgary, Alberta, Program and Abstracts, p105. O'Connel, S . C , Dix, G.R., Barclay, J .E. , 1990. The origin, history, and regional structural development of the Peace River Arch, Western Canada. Bulletin of Canadian Petroleum Geology, v38A, p4-24. Plint, A .G . , 1988. 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Seismic stratigraphy and sedimentary facies of the Middle Triassic strata, Western Canada Sedimentary Basin, Northeast British Columbia. Unpublished Phd thesis, University of Alberta, Edmonton, 219p. Reinson, G.E. , 1992. Transgressive barrier island and estuarine systems. ]n R.G. Walker and N.P. James, edits., Facies Models. Response to Sea-Level Change. Geological Association of Canada, p. 179-194. Salazar-Jiminez, A., Frey, R.W., Howard, J.D., 1982. Concavity orientations of biavalve shells in estuarine and nearshore shelf sediments, Georgia. Journal of Sedimentary Petrology, v.52. P565-586. Singh, P.P. and Singh, I.B., 1992. Cross-bedding with tidal bundles and mud drapes. Evidence for tidal influence in Bhuj Sandstone (Lower Cretaceous), Eastern Kachchh. Journal of the Geological Society of India, v.39, p.487-493. Styan, W. and Shaw, J . , 1991. An overview of Triassic Halfway pools in the Progress area (abstract). Opportunities for the Nineties, Canadian Society of Petroleum Geologists Convention, Calgary, Alberta, Program and Abstracts, p.107. Swift, D.J.P. and Thorne J.A., 1991. Sedimentation on continental margins 1: a general model for shelf sedimentation, in D.J.P. Swift, G.F. Oertel, R.W. Tillman, J.A. Thorne, edit., Shelf sand and sandstone bodies, geometry, facies, and sequence stratigraphy. International Association of Sedimentologists Special Publication 14, p.3-31. Walker, R.G., and Plint, A .G . , 1992. Wave- and storm-dominated shallow marine sytems. in R.G. Walker and N.P. James, edit., Facies Models. Response to Sea-Level Change. Geological Association of Canada, p. 219-238. Wittenberg, J . , 1992. Origin and stratigraphic significance of anomalously thick sandstone trends in the Middle Triassic Doig Formation of west-central Alberta. Unpublished M.Sc. thesis, University of Alberta, Edmonton, Alberta. 600p. Young, F.G., 1997. Iconoclastic view of mid-Triassic stratigraphy, Umbach-Wargen area, British Cloumbia. Bulletin of Canadian Petroleum Geologists, v45, p. 577-594. 45 CHAPTER 3 Diagenesis, Reservoir Quality and Production Trends of Doig Formation Sand Bodies in the Peace River Area of Western Canada 3.1 . -ABSTRACT Sand bodies of the Middle Triassic Doig Formation are composed of well sorted sub-lithic- to quartz arenites and bioclastic packstones to grainstones deposited in a shoreface environment. The sand bodies lie along a SSE trend related to the position of the original Doig shoreline. The trend is tilted into the Peace River Basin as a result of periodic reactivation of the Dawson Creek Graben Complex and subsequent sediment loading over the southern portion of the reservoir trend. Effective porosity is primarily inter-granular in the sandstone facies with significant moldic and vuggy porosity developed in the coquina facies at the West Stoddart and Cache Creek fields. Average porosities range from 6.5 - 9 .5% for sandstone lithofacies and 4.9 - 8.6% for coquina lithofacies. Pore occluding cements are mainly calcite in the northwest part of the reservoir trend to dolomite and anhydrite in the southeast. Sand bodies with only minor interstitial calcite have extensive porosity loss by compaction and precipitation of authigenic quartz. An exploration fairway for Doig sand body exploration is constrained with production and core analysis data, structural and depositional models, thermal maturity data and diagenesis. Reservoir quality and production from Doig Formation sand bodies in the Peace River area of Western Canada are significantly impacted by the preservation of inter-granular 46 porosity and fracturing related to the distribution of early calcite cement. Early calcite cements were sourced from bioclastic debris and calcareous mudstones deposited coeval with major sands. Diagenetic controls along the northwest-southeast reservoir trend include the precipitation of calcite in the near surface and shallow burial realm, the creation of fractures and faults in cemented intervals and the dissolution of cements and framework grains in three identifiable episodes. Multiple dissolution phases during diagenesis created moldic, vuggy and inter-granular secondary porosity. The formation of open fractures during early diagenesis enhanced both the secondary porosity and the permeability of the West Stoddart and Cache Creek Doig pools. Production data from the Valhalla, Sinclair, West Stoddart, Cache Creek and Buick Creek fields reflects the control of diagenesis on porosity and permeability. 3.2. - INTRODUCTION Shallow marine sandstone reservoirs of the Triassic Doig Formation follow a north-west to south-east trend from the Tommy Lakes field in northeastern British Columbia to the Valhalla field in west-central Alberta (Fig. 1). Since the first major discovery at Buick Creek in 1976, production from this trend in British Columbia has been approximately 20.6 x10 6 m 3 oil and 20.0 x 10 6 E 3 m 3 gas (Govt, of B C data, July, 1999). Doig pools are characterized by erratic production declines and an uneven distribution of effective porosity. Several published studies describe the lithology, stratigraphy and depositional environments for various Doig pools (Wittenberg, 1991, and Evoy and Moslow, 1995), but no study documents the paragenetic history, the controls on reservoir quality or production history. This paper describes and discusses the relationship between 47 Fig. 3.1 - Study Area : Oil and Gas Fields of the Doig Reservoir Trend : TL = Tommy Lakes, B C = Buick Creek, FW = Fireweed, C C = Cache Creek, W S = West Stoddart, Si = Sinclair, V= Valhalla, R = Rigel, G B - Groundbirch, S = Scott, K = Kildkerran, TR = Two Rivers, F = Ft. St. John 48 lithofacies, diagenesis and production from Doig sand bodies in northeastern British Columbia and incorporates data from Doig fields in west central Alberta to provide a regional perspective. The specific objectives of this study are to establish: 1) the timing and distribution of diagenetic phases documented through S E M and conventional petrography; 2) the relationship between lithofacies, diagenesis, and porosity and permeability; and 3) the relationship between production and thermal maturity, structure, stratigraphy, lithofacies and diagenesis. A predictive model is presented for the distribution of reservoir quality sands along the Doig reservoir trend in the Western Canada Sedimentary Basin (WCSB). 3.3. - LITHOLOGY & DEPOSITIONAL SETTING The Doig Formation in the study area (Fig. 2) consists of mudstone, siltstone and sandstone, deposited as part of a major Middle Triassic regressive clastic wedge on the western margin of the Pangean super-continent (Gibson, 1990). Locally, thick sand bodies consisting of fine-grained quartz arenite and carbonate bioclasts occur scattered along the Doig sub-crop trend. In northeastern British Columbia the sand bodies are interpreted as shallow marine deposits (Evoy and Moslow, 1995, Evoy, 1997 and Harris and Bustin, submitted) and their distribution reflects the trend of the paleo-shoreline during Doig time. The depositional environments of Doig sand bodies in this study are described in a companion paper (Harris and Bustin, submitted). Doig sand bodies deposited in Alberta appear similar in geometry and lithology and are described as estuarine channel fill by Cant (1986) or shoreface sourced mass-wasting events by Wittenberg (1992). Ten major lithofacies grouped into two facies associations are recognized in this study from core (Table 1). Sand bodies are comprised of 49 00/11-35-087-22W6 - SUNCOR CACHE CREEK Period/Epoch/Age Environment of Deposition Fig. 3.2 - Sequence Stratigraphic framework and environments for Triassic strata within the study area (modified from Gibson and Barclay, 1989 and Gibson and Edwards, 1990). TST - transgressive systems tract, M F S - maximum flooding surface, FS -flooding surface, 2nd/3rd S B - second/third order sequence boundaries. 50 Facies Assoc. Facies Description 1 a Laminated Mudstone dark qrey to black mudstone and siltstone, planar laminated, organic-rich, calcareous, rare vfq sandstone laminae, abundant fractures and pvrite, absence of bodv and trace fossils b Bioclastic Mudstone dark qrey to black brachiopod packstone, massive, calcareous, matrix dominantly muddy, rare siltv to vfg sandstone, bioclasts are typically delicate non-abraded brachiopod plus minor pelecypod and echinoderm debris c Laminated Siltstone dark to medium grey siltstone and vfq sandstone, planar to wavy laminated, cm scale convolute inter-bedded vfq sandstone, calcareous, abundant cut-and-fill structures, rare Hz traces, scattered echinoderm and brachiopod debris 2 i , i i a Muddy Sandstone liqht qrey vfq quartz sandstone and mudstone, ripple laminated to x-bedded, abundant cut-and-fill structures, load casts, mudstone rip-ups, calcareous, moderately abundant horizontal traces, synaeresis cracks, rare bivalve fossils b Massive Sandstone brown to liqht qrey vfq-fg quartz sandstone, massive, moderately sorted, sub-anqular, calcareous, abundant mudstone rip-ups, calcite cements visible as concretions, traces absent, rare abraded bioclastic debris c Laminated Sandstone brown to liqht qrey vfq-fq quartz sandstone, low to hiqh anqle laminated to x-laminated, HCS, moderately sorted, subanqular, calcareous, abundant mudstone rip-ups, calcite cements visible as concretions or in zones followinq primary structure, rare bioclastic debris and traces. d Bioclastic Sandstone liqht qrey vfq-fq quartz sandstone as above with 20-30% coarse sand to pebble sized abraded bioclastic debris, massive to planar laminated, abundant visible interqranular calcite, rare vuqqy porosity, traces absent e Interbedded Sandstone/Coquina brown to liqht qrey vfq-fq quartz sandstone as in 2c interbedded with pelecypod coquina, abraded bioclasts, abundant lithic clasts and mudstone rip-ups, abundant visible calcite appears related to bioclastic material, coquina can appear as isolated lenses or breccia clasts in a sandstone matrix, rare traces f Coquina liqht qrey coquina, 60-90% abraded bivalve bioclasts in a fq quartz sandstone matrix, x-bedded (normal and inverse), moderately to poorly sorted, bioclasts moderately imbricate, abundant mudstone rip-ups, visible intergranular calcite, traces absent g Mudstone Breccia Granule to pebble breccia, mudstone clasts in a vfq -fq quartz sandstone matrix, imbricate, rounded to anqular clasts, poorly sorted, mudstone, semi-lithified deformation structures, rare bioclastic debris, traces absent Table 3.1 - Facies Descriptions lithofacies within association 2 and are either sheet sand bodies, incised by 10-30 metre thick channel-like bodies up to 5 kilometres in length, or as a larger shoreline parallel elongate sand bodies 1 0 - 2 0 metres thick and over 20 kilometres in length (Fig. 3). Sheet sandstones have a gradational contact with underlying mudstones and siltstones of association 1, coarsen upwards and generally range from structureless to convolute and ripple laminated. Channel sandstones have an abrupt contact with underlying mudstones and siltstones of association 1 and consist of stacked, fining upward packages of parallel to low-angle laminated sandstones and bioclastic debris. The large elongate sand body rests sharply on mudstones and siltstones of association 1 and consists of massive to coarsening-upward cycles of fine-grained parallel laminated sandstone and bioclastic debris. The upper contact is marked by an erosive lag and is interpreted as a trangressive surface of erosion. Doig sand bodies contain rare whole fossils and a sparse trace fossil assemblage, limited to vertical escape structures, Skolithos and Ophiomorpha. Both reservoir and non-reservoir quality sands have undergone extensive diagenetic modification including: extensive early calcite cementation, fracturing, authigenc quartz formation, dolomitization and late stage porosity enhancement by dissolution. 3.4. - DATABASE The present study is based on core and core data from 45 wells taken from productive and non-productive Doig sand bodies in northeastern British Columbia, and core and production data (from the Government of British Columbia Oil and Gas Commission database) for an additional 110 wells along the reservoir trend. The majority of cores incorporated in this study are from the Buick Creek, West Stoddart, Fireweed and 52 Fig. 3.3 - Total Doig sand isopach within the study area. 53 Cache Creek fields. Core from the Tommy Lakes, Rigel, Groundbirch, Kilkerran, Scott, Ft. St. John and Two Rivers fields are also incorporated into the study. Representative samples were cut from each lithofacies for comprehensive petrographic and scanning electron microscope (SEM) analyses. Petrologicaly, dolomite and ferroan calcite were distinguished from non-ferroan calcite through the use of the Alizaren Red and Potassium Ferricyanide staining technique (Dickson, 1965). Conventional core analysis data were obtained from the Oil and Gas Commission of British Columbia. Production data for pools in British Columbia and Alberta was obtained from the government database updated to March 1999. Analysis of production trends in deviated and non-deviated well are restricted to the initial 6 months of production by a given well as a basis for meaningful comparisons. Declines are analyzed over the first six months of production for deviated and non-deviated oil wells only. 3.5. - PETROLOGY OF DOIG SAND BODIES 3.5.1. - S A N D S T O N E COMPOSITON Doig sandstones are sub-lithic- to quartz arenites using the classification of McBride (1963). Detrital quartz is the dominant component, followed by minor detrital dolomite, apatite, calcite and microcline. In the Stoddart reservoir, detrital apatite comprises up to 15% of the framework grains. Apatite coated dolomite and quartz grains are common in all core samples. Detrital quartz is very fine-grained to fine-grained, sub-rounded and well sorted, generally monocrystalline with rare occurrences of polycrystalline quartz and chert. Detrital quartz grains include rounded rims of authigenic quartz indicating 54 prior lithification, burial, exhumation and reworking. Open porosity is primary and secondary inter-granular. 3.5.2. - COQUINA COMPOSITION Coquina facies of the Doig Formation range from bioclastic wackestones to packstones, using the classification of Dunham (1962). Bioclasts are partly to completely recrystallized, highly abraded and difficult to identify in the majority of samples. The characteristic fibrous and two-layer inner structure of individual bioclasts, and the shape and packing of the bioclasts is indicative of brachiopod and bivalve shells (Adams et al., 1984). Bioclasts are well to poorly sorted, and are generally imbricated, consistent with the primary sedimentary texture of surrounding sandstones. The matrix lithology is as described above for sandstone composition. Porosity is secondary, present as moldic or intra-granular pores. 3.5.3. - DIAGENESIS A number of diagenetic processes and cements are recognized in this study. Calcite, quartz, dolomite and anhydrite are the most abundant pore-filling minerals and their distribution controls reservoir quality. Other diagenetic constituents include apatite and minor amounts of pyrite and feldspar. The cements are described below and an analysis of the paragenetic sequence is presented in the following section. 55 Fig. 3.4 - (a) Spherical calcite concretions in laminated fine-grained sandstone (Cache Creek, 4-03-88-22W6). (b) Continuously calcite cemented fine grained sandstone interval, distribution of calcite within this core is patchy (Fireweed, d-42-H/94-A-13). c) Discrete interval of calcite cement in fine-grained stratified sandstone (Buick Creek, d-76-l/94-A11). 56 3.5.3.1. - Calcite Cement Calcite cement occurs locally in sandstone as discrete cemented layers and scattered concretions, or less commonly as continuously cemented sandstone or fracture fill (Figs 4a,b,c). Layers and concretions range in thickness from a few centimetres to 1 metre and are associated with bioclastic debris or calcareous mudstone intra-clasts. In the sandstone lithofacies, calcite is either poikilotopic (Fig. 5a) or isolated subhedral crystals; both styles of cement fill inter-granular porosity. Calcite often replaces detrital quartz (Fig. 5b) and dolomite grains and authigenic dolomite and quartz cements. Calcite cements either nucleate on detrital carbonate grains (Fig. 5c) radiating outwards or occurs as cementation fronts, replacing detrital quartz and carbonate grains (Fig. 5d). In the coquina lithofacies calcite cement is fine to coarsely crystalline spar completely filling inter-granular porosity, or is coarse, blocky spar within large vugs and moldic pores. Non-ferroan calcite is the most common cement present, forming concretions and layers within Doig sandstones, ferroan calcite is less common as a pore filling cement, exhibiting ferroan zones within coarse euhedral calcite crystals (Fig 5e). 3.5.3.2. - Quartz The importance of quartz cement in Doig sand bodies is variable, related to depth of burial and the distribution of earlier carbonate cements. Authigenic quartz occurs as euhedral overgrowths (Fig. 6a) precipitated on detrital quartz grains. Quartz is an abundant pore filling cement in relatively deep Doig reservoir such as Kilkerran and Groundbirch (>2050 metres TVD), but much less significant in shallower reservoirs such as Buick Creek (<1400 metres TVD). Quartz cements can be abundant in shallow 57 Fig. 3.5 - a) Poikilotopic calcite cement in concretion of the Cache Creek field, b) Calcite at Buick Creek replaces both detrital quartz and carbonate grains. Note corroded boundaries of quartz grains (Q(corr). c) Intergranular calcite cement nucleates off existing detrital carbonate grains, d) S E M image of quartz and detrital carbonate grains being replaced along a front. (Q =quartz, C a = calcite, K = potassium feldspar, D = dolomite, dCa = detrital carbonate, Ap = apatite), e) Ferroan zoned coarse grained euhedral - subhedral calcite cements infilling porosity at Buick Creek. 58 sand bodies such as the calcite cement-poor Doig sandstones of the Tommy Lakes field. 3.5.3.3. - Apatite Apatite coats quartz and detrital carbonate grains throughout the field area. Apatite peloids and coated grains are most abundant in the West Stoddart and Cache Creek fields where they can form 5 - 20% of the framework grains. 3.5.3.4. - Dolomite Dolomite cements predominantly occur as isolated rhombs typically nucleated on detrital dolomite grains (Fig. 6b), peloids or bioclasts. Sand bodies in the northern part of the reservoir trend such as Buick Creek have minor pore-filling dolomite compared to reservoirs to the south such as Sinclair, where dolomite forms the dominant cement (Wittenberg, 1992). Where Doig sands directly underlie Halfway sandstones in the eastern section of the study area (Rigel), dolomite cements form the dominant pore-filling and replacing cement (Fig. 6c). 3.5.3.5. - Anhydrite In northeastern British Columbia, rare anhydrite cements occur as large isolated poikiolotopic crystals that fill primary and secondary pores and replace earlier calcite 59 Fig. 3.6 - Photomicrograph and core images of Doig sandstone, a) S E M image of quartz overgrowths on detrital quartz grains in the Fireweed field, b) Backscattered S E M image of pore filling dolomite nucleating on a corroded quartz grain in the West Stoddart field, c) Photomicrograph in plane polarized light showing euhedral dolomite crystals rimming framework quartz grains east of the Buick Creek field, d) Syn-sedimentary compaction features in core of the Cache Creek field. Bedding and laminae highlighted with dashed lines show drape over concretion. Q = quartz, Ap = apatite, D = dolomite 60 cements. Anhydrite is a major pore-filling cement in Doig sandstone reservoirs in west central Alberta (Wittenberg, 1992). 3.6. - PARAGENESIS The paragenesis of Doig sandstones based on S E M , petrography and geochemical considerations is summarized in Figure .7. Interpretation of the paragenetic sequence is complicated by multiple episodes of sedimentation, diagenesis, exhumation and subsequent reworking. The appearance of rounded dolomite rhombs and other cement grains suggests that Doig sand bodies are composed at least in part of reworked previously lithified sedimentary rocks. 3.6.1. - E A R L Y CALCITE PRECIPITATION Early calcite is locally the most important cement in Doig sandstones, occluding nearly 100% of inter-granular porosity. Early calcite concretions and cemented layers are common at Buick Creek, Cache Creek, Fireweed and West Stoddart but absent in Doig fields further southeast along the reservoir trend. Differential compaction and the preservation of primary porosity in core indicates that mechanical compaction took place subsequent to concretion formation at both a macroscopic and microscopic level. Differential compaction between concretionary and non-concretionary sandstones (Fig. 6d) indicates that concretion formation was syn-sedimentary, occurring at or near the sediment-water interface. The high percentage of occluded inter-granular porosity (Fig. 5d) and the absence of authigenic quartz within concretions also indicates early 61 Early Diagenesis Late Diagenesis Apatite grain coaitings Calcite concretions/layers Fracturing Moldic/intragranular porosity Compaction Quartz Replacement Ferroan Calcite Spar Secondary Porosity Anhydrite Dolomite Hydrocarbon Charge Porosity vs Depth (%) 30 20 10 porosity creation " | porosity I destruction other phases ? I 10m 1000m eodiagenesis early mesodiagenesis late mesodiagenesis Fig. 3.7 - Generalized paragenetic sequence and evolution of porosity of the Doig sandstones in the study area. Line thickness reflects significance of diagenetic phase to porosity formation or destruction. 62 precipitation of calcite cement, as compared to sandstone across the concretion boundary. Similar early calcite concretions and continuously cemented layers have been reported in Lower Cretaceous deltaic-marine sandstones of the Hibernia oilfield (Hesse & Abid, 1998) and shoreface sandstones of the Middle Jurassic Valtos Formation, Scotland (Walderhaug & Bjorkum, 1998). 3.6.2. - FRACTURING AND MICROFAULTING Fractures and microfaults are visible in core in all fields except Rigel, Scott and Kilkerran. The fractures are vertical to sub-vertical, hairline or up to 0.5 centimetres wide and are generally confined to calcite concretions and cemented layers. Microfaults have similar characteristics and are offset up to a few centimetres. Fractures can be sand filled, open, or partially to completely calcite filled. Sand filled fractures (Fig. 8a) are interpreted as early based on cement and fill textures, forming after the precipitation of early calcite but subsequent to significant burial and lithification. The texture of the sand fill indicates that the fill was not consolidated when introduced into the fractures. Open and calcite filled fractures (Figs. 8b and 8c) are abundant in the West Stoddart and Cache Creek fields and are also interpreted as early. The appearance of pendant coarsely crystalline calcite spar on the roof of a large fracture associated vug (Fig. 8b) suggests formation of open fractures in a vadose environment prior to significant burial. The restriction of early fractures to calcite concretions and cemented layers is a consequence of overburden loading and a consequence of the mechanically more competent calcite cemented sandstone relative to uncemented sandstone. Core analysis data show that extensive fracturing is also present in the Valhalla field of western Alberta. 63 Fig . 3.8 - Fractures in Doig sand bodies, a) Early fractures south of the Buick Creek field (15 21 87 20W6). Note lower spar-lined fracture, b) Partially filled early fractures and vugs in the West Stoddart field (14 31 87 21W6). Note large euhedral calcite crystals on the top surface of the vug. c) Late calcite filled fractures in the Fireweed field (b-26-D/94-A-14). The fracture is constrained to the cemented region. F ig . 3.9 - a) Stylolite cross-cutting calcite cemented quartz sandstone in the Buick Creek field. Note truncation of detrital quartz grains, b) Authigenic quartz phase corroded and replaced by dolomite cement in the Groundbirch field. aQ = authigenic quartz, Q = quartz, D = dolomite, dC = detrital calcite. 64 3.6.3. - FORMATION OF MOLDIC AND INTRA-GRANULAR POROSITY Moldic and intra-granular pores are abundant in the coquina and inter-bedded sandstone and coquina of lithofacies 2e and 2f of the Stoddart/Cache Creek and Buick Creek fields. The fill of molds and vugs by geopetal sandstone indicates the dissolution of bioclasts near the sediment-water interface. Dissolution of bioclastic material was the primary source for early calcite cements. 3.6.4. - COMPACTION The majority of the original porosity in Doig sandstones was eliminated by mechanical compaction through grain slippage and rotation during shallow burial and by pressure solution with increasing depth of burial. Evidence for mechanical compaction is the abrupt reduction in primary porosity observed across concretion boundaries. Evidence for pressure solution includes truncated bioclasts, horizontal stylolites (Fig. 9a), and embayed and concave-convex quartz grain contacts. Contact between ferroan calcite and dolomite cement along euheral quartz boundaries (Fig. 9b) indicates authigenic quartz precipitation prior to the formation of later calcite and dolomite cements. 3.6.5. - R E P L A C E M E N T OF QUARTZ BY C A R B O N A T E Detrital quartz grains are corroded and replaced by calcite. Quartz grains within calcite cemented layers and concretions (Fig. 5d) are the most extensively replaced. The high percentage of preserved primary porosity and the negligible permeability of the calcite 65 concretions and cemented layers to fluid flow suggest that the dissolution of the quartz grains occurred during the formation of the early calcite cement. Later stage ferroan calcite and dolomite also replace quartz grains although not as extensively as the early calcite. Petrographic evidence indicates three separate stages of quartz dissolution. The first stage occurred during shallow burial and was the most corrosive, the second and third stages occurred later during deep burial with accompanied precipitation of ferroan calcite and dolomite. 3.6.6. - PRECIPITATION OF F E R R O A N CALCITE Coarsely crystalline calcite spar occludes up to 100% of primary inter-granular, vuggy and moldic porosity. The equant drusy mosaic of infilling spar is often zoned with ferroan calcite (Fig. 5e) indicating precipitation as burial cement associated with reducing conditions (Tucker and Wright, 1990). Contact relationships between euhedral quartz crystals and burial calcite indicate that calcite precipitation followed the formation of authigenic quartz. 3.6.7. - C A R B O N A T E DISSOLUTION - S E C O N D A R Y POROSTIY Dissolution of inter-granular and replacing cements form secondary porosity to varying degrees. The appearance of irregular oversized pores, partially dissolved and floating quartz fragments, and corroded grain boundaries of authigenic quartz and ferroan calcite all indicate the formation of secondary porosity subsequent to the formation of both authigenic quartz and ferroan calcite cements. 66 3.6.8. - DOLOMITE PRECIPITATION Replacement of carbonate and quartz grains and cements and infill of secondary pores by euhedral dolomite rhombs represents the final stage of cement precipitation. The absence of corroded dolomite crystal grain boundaries and the replacement of ferroan calcite cement indicates that the dolomite cement post-dates all other diagenetic events. 3.6.9. - H Y D R O C A R B O N MIGRATION The introduction of hydrocarbons represents the final stage in the paragenetic sequence. Where present, hydrocarbons line primary and secondary pores on the outer margins of all cement crystals. 3.6.10. - G E O C H E M I C A L CONSIDERATIONS Reactions between the organic and inorganic constituents of Doig sandstones during diagenesis controls the formation of the early calcite cement, the subsequent dissolution and replacement of quartz by calcite, and the formation of secondary porosity. The source of early calcite cement was the dissolution of bioclastic grains at the sediment-water interface by C 0 2 production during the bacterial oxidation of organic matter (Molenaar, 1998, and de Souza and de Assis Silva, 1998). In marine sediments, a zone of bacterial sulphate reduction generally lies a few centimetres below the upper layer of aerobic sediments (Curtis, 1978 and Berner, 1981). Reduction 67 of iron oxides in this zone increases the alkalinity of pore waters and enhances carbonate precipitation (Berner, 1984), resulting in an early phase of calcite cement. The dissolution of quartz during sandstone diagenesis is commonly documented (ie. Hayes, 1979) but not accounted for in the literature. Sulphate reduction and methanogenesis reactions, and increasing temperatures during burial increase the alkalinity of pore fluids which increase the solubility of quartz, likely to the point of dissolution. The formation of secondary porosity requires the dissolution of inter-granular and replacement carbonate cements. Schmidt and Macdonald (1979) and others suggest that the carbonic acid required to dissolve the carbonate cement in buried sandstones be generated by the decarboxylation of organic matter in adjacent strata. In Doig sandstones, the adjacent strata are underlying organic-rich mudstones and siltstones. The maximum acidity in organic matter-rich shale is reached within a temperature range of 80 - 100°C (Dypvik, 1983; Pearson et al., 1983) corresponding to the onset of liquid hydrocarbon generation. The formation of secondary porosity was thus likely coincident with, or prior to, hydrocarbon charging of the Doig reservoir. 3.7. - R E S E R V O I R Q U A L I T Y Reservoir quality of Doig Formation sand bodies was evaluated using core analysis data from 68 wells in northeastern British Columbia and west central Alberta. Reservoir grade lithologies are quartz arenites and sub-litharenites of Facies 2b, 2c and 2e, and the bioclastic sandstones and coquinas of Facies 2d and 2f. Core permeability and porosity data were obtained from conventional analysis of of core plugs taken at 68 approximately 0.1 to 0.5 metre intervals. The lithology corresponding to analyzed core intervals was identified from core in British Columbia and from core analysis descriptions in Alberta. Average values of porosity and permeability ranges for clean sandstones from the various fields along the reservoir trend range from 6.0% to 9.4% and from 0.7 mD to 34.4 mD (Table 2). Average values for the coquina lithofacies range from 5.2% to 8.6% and 0.35 mD to 10.7 mD. The utility of core analysis data lies in the capacity to correlate trends of porosity and permeability to mappable variables such lithofacies or cement distribution. In any useful examination of reservoir quality data, a correlation must be made between some mappable variable such as lithofacies or cement distribution and porosity/permeability. In this study the present depth of the reservoir, the distribution of bioclastic material and the distribution of secondary porosity are examined with respect to reservoir quality. Field Facies Porosity(%) Km ax (mD) n Average Std.dev Average Std.dev Stoddart/ Cache sandstone 7.0 4.4 23.2 53.2 180 coquina 6.6 2.9 10.7 28.4 30 Buick Creek sandstone 9.4 3.9 14.9 21.4 578 coquina 8.6 3.5 4.4 10.1 84 Fireweed sandstone 7.6 3.7 34.4 47.2 111 Sinclair sandstone 7.0 3.3 1.5 4.9 941 coquina 4.9 2.4 0.4 0.7 88 Valhalla sandstone 6.5 3.0 1.8 5.6 546 coquina 7.8 4.0 7.6 17.9 520 Table 2. Average porosity and permeability values for fields within the Doig reservoir trend. Sandstone represents facies 2b,2c and 2e and Coquina represents facies 2f. 69 3.7.1. - TREND OF POROSITY AND PERMEABILITY WITH DEPTH There is no correlation between porosity, permeability and true vertical depth (TVD) of Doig reservoirs of similar grain size and lithology (Figs. 10a and 10b). The TVD reflects the present day depth not the maximum depth of burial. Data from Bustin (1999) shows a northeast to southwest trend of increasing depth of overburden removed by uplift and erosion that is consistent with the depth trend from Figures 10a and 10b. Many authors have published data showing a strong relationship between decreasing porosity and permeability with increasing depth of burial of sandstones (Taylor, 1950, Galloway, 1974, Hsu, 1977 and Selley, 1978). However, as depth of burial increases in Doig reservoirs, there is no corresponding decrease in porosity and maximum permeability from core samples. At the time of deposition, clean well-sorted sandstone has an initial porosity of about 35 - 40% (Hayes, 1979). Porosity values given in Table 2 indicate a significant reduction in porosity due to the effect of physical and chemical compaction. Evidence of compaction and pressure solution related pore destruction increasing with depth is evident from examination of thin sections of Doig sandstone. Carbonate cements initially preserve primary pores and are subsequently dissolved to create new secondary pore networks, disallowing a negative relationship between depth, and porosity and permeability. 70 20 15 t 10 2 o Q_ CO <D J £ CO _ l >, E E ,o 1000 CD o u ZJ CO • ir o cc o CO 0 CO cc 0 1500 2000 True Vertical Depth (m) • 2500 Fig . 3.10a - True vertical depth of Doig pools versus core porosity of vfg - fg sandstone F ig . 3.10b - True vertical depth of Doig pools versus core maximum permeability of vfg -fg sandstone facies 71 3.7.2. - BIOCLASTIC FACIES AND CALCITE C E M E N T DISTRIBUTION Bioclastic units in Doig sand bodies consist of reworked bivalve and brachiopod shells that act as both a source of calcite cement and as reservoir rocks. The coquina lithofacies is localized in the southern portion of the Buick Creek field and in the distributary channel fills of the West Stoddart and Cache Creek fields (Fig. 11). Bioclastic debris at Fireweed (well b-26-D) is a breccia, reworked from a previous deposit. The bioclastic facies in the channel fill and shoreface facies are in beds oriented parallel to the overall sedimentary fabric. At Valhalla, West Stoddart and Cache Creek, the coquina lithofacies has sufficient effective porosity to be a reservoir rock. At Buick Creek, the porosity of the coquina lithofacies is isolated and ineffective. Porosity versus permeability plots (Fig. 12a, 12b) illustrate the lower permeabilities of the coquina lithofacies at the West Stoddart and Cache Creek fields than at the Buick Creek field. 3.7.3. - DISTRIBUTION OF S E C O N D A R Y POROSITY Secondary porosity is the main open porosity type in productive Doig sand bodies of northeastern British Columbia. Secondary porosity varies in significance between different fields along the reservoir trend. Secondary porosity in the form of dissolved authigenic cements and sedimentary grains, can mimic the pore sizes and textures of primary porosity (Schmidt and McDonald, 1979) and is generally difficult to distinguish from primary porosity in sandstone. Qualitatively, the distribution of secondary porosity is associated with the presence of open and calcite filled fractures, and the distribution of the early calcite cement. Fractured sand bodies such as West Stoddart have 72 • » * * « ® # *® . • • • : • « « ® • • • * Fireweed * •* • • • *®«? • » ® • • ®* • • « » • • « • » ® « ® » ® » # « • * ^ « *#» » « • « » • «•*# *t* %* • • • • • • r fi * * Buick Creek m « ® ® Cache , Creek • • « West Stoddart * / • • • • • # • • * • • • • ® ® * ** ® • 5 * < • • • * • • * • • * * 1 • • • * Doig Formation penetration (jl^) Occurance of bioclastic facies in core 0 10km UBC DOIG STUDY Bioclastic Facies Map Fig. 3.11 - Occurrence of bioclastic facies in cored Doig sandbodies 73 100000 10000 ID CU 1000 lidai 100 1 10 X 1 --co E O) 0.1 -o 0.01 • 0.001 --a o ss • coquina | —t rend 10 Porosity (%) 15 20 Fig. 3.12a - Core porosity versus core permeability of the Doig sand body at Buick Creek. Trend lines indicate significantly lower permeabilities for the coquina facies than the sandstone facies for a given porosity 100000 10000 § 1000 o s s • coquina! 10 Porosity (%) 15 20 F ig . 3.12b - Core porosity versus core permeability of the Doig sandbodies at West Stoddart and Cache Creek. Coquina and sandstone lithofacies fall along the same trend 74 abundant secondary pores while sand bodies with a low percentage of interstitial carbonate have a dense packing of quartz grains and a much higher percentage of primary to secondary porosity. 3.8. - PRODUCTION TRENDS In order to relate production data to diagenesis, lithofacies and reservoir quality, a meaningful basis of data comparison is required for wells of varying age, net pay and hydrocarbon type. In this study oil production decline is examined at West Stoddart/Cache Creek and Buick Creek, and average daily gas and oil production for wells at the West Stoddart/Cache Creek, Fireweed, Buick Creek, Valhalla and Sinclair fields (Table 3). Production in British Columbian reservoirs flowed unrestricted during the period over which the data was collected (P. Aterawall, pers. comm.). Production in Albertan fields was restricted based on the thickness of the producing interval (G. Kaswell, pers. comm.). Average production and declines are calculated over the first six months of production for horizontal and vertical wells. Decline is calculated here by dividing the average daily production of a well in its sixth month of production by the average daily production of a well in its first month of production. Calculating decline with two points is not meant to suggest that Doig pools undergo linear decline, it is just a convenient method of comparison. A six months time frame was chosen in order to compare the older wells of Buick Creek with the younger wells of West Stoddart and Cache Creek. 75 Decline Factor (%) Average Production FIELD oil (m3/d) gas(E3m3/d) n dev. non-dev. dev. non-dev. Buick Creek (oil) 54.0 59.2 75.1 14.1 34d (gas) 32.3 9.4 18nd Stoddart/Cache (oil) 38.5 18.5 65.6 34.8 30d (gas) 52.3 31.2 5nd Fireweed (oil) 7.8 23.0 1d (gas) 0.8 6.1 3nd Valhalla (oil) 10.1 25.5 1d (gas) 9.1 15.1 20nd Sinclair (gas) 169.8 139.7 2d 19nd Table 3. Decline factors and average production for deviated and non-deviated wells in Doig fields. Decline factor and production values are calculated using data from the first and sixth month of production only. N is the number of deviated (d) and non-deviated (nd) wells used in the calculation of averages and declines. Declines at Stoddart/Cache Creek and Buick Creek are portrayed graphically as cross-plots of the average daily production for the first month of productions versus the average daily production for the sixth month of production (Fig. 13a,b). The data indicates significantly higher declines after six months for deviated and non-deviated wells at West Stoddart/Cache Creek in comparison to those at Buick Creek. Vertical wells at Stoddart/Cache Creek have a constant decline factor and a much higher range of initial production rates. In contrast, non-deviated wells in the Buick Creek field have highly variable decline factors ranging from 6 to 530%. Average gas and oil production for horizontal and vertical wells was calculated for the five primary Doig fields along the reservoir trend (Fig. 14). Deviated wells exhibited higher production rates than non-deviated wells at all fields except Valhalla and 250 ! 200 co 1 150 e o E sz *•> (0 100 50 o4^ x non-deviated o deviated — — no decline X L 0 50 a) West Stoddart/Cache Creek 100 150 200 250 1st month (m /day) 250 200 CO co 150 E E sz ** CO 100 50 o x non-deviated o deviated — —no decline o ^ o o o o o o o v ^ O cx xo o _ X x Q— o oo o o • i"" 50 100 150 200 250 b) Buick Creek 1st month (m /day) Fig. 3.13 - Cross-plot of average daily oil production in the first and the sixth month of continuous production from Doig pools. Graphed points reflect the production decline in the first sixth month of production for deviated and non-deviated wells, a) Declines in theWest Stoddart and Cache Creek fields. Note the linear trend of non-deviated wells, b) Decline in the Buick Creek field. Note the lower declines in Buick wells in comparison toWest Stoddart and Cache Creek 77 average oil production m7day per well for 1st 6 months in non-deviated wells average oil production m3/day per well for 1st 6 months in deviated wells average gas production E3m3/day per well for 1st 6 months in non-deviated wells average gas production E3m3/day per well for 1st 6 months in deviated wells Doig pool with production data RNGE 13 11 09 07 Fig. 3.14 - Average daily oil and gas production rates from Doig reservoirs. Production figures represent an average of daily production rates of all wells in each field with production data. In order to produce a meaningful comparison, production from deviated and non-deviated wells were separated and average production for each well was calculated for the first six months of production only. 78 Fireweed. The Sinclair field has the highest average daily gas production and no reported oil production. The Fireweed field has the lowest average daily gas and oil production in deviated and non-deviated wells. The Stoddart/Cache field produces at significantly higher gas and oil rates for non-deviated wells than the Buick Creek field but a lower oil rate in deviated wells. 3.9. - DISCUSSION Diagenesis controls porosity, permeability and production observed along the Doig reservoir trend. The distribution of fractures, secondary porosity and cement are critical for reservoir development. The following section describes the relationship between diagenesis, reservoir quality and production in reservoir and non-reservoir sand bodies. The lithology and grain size of sandstones are relatively uniform between sand bodies enabling comparison. The presence and the proportion of bioclastic beds distinguishes individual sand bodies along the reservoir trend. Wittenberg's (1992) investigation of Doig sandstones in west central Alberta and this study show a predictable distribution of cements along the reservoir trend. Dolomite and anhydrite cements are the dominant cements in the southeastern part of the reservoir trend, while calcite is the dominant in the northwest. Wittenberg (1992) makes no mention of secondary porosity in his study of sand bodies at Wembley and Sinclair. The absence of secondary pores may be related to the lower solubility of anhydrite and dolomite to acidic pore fluids responsible for calcite dissolution within the northwestern section of the reservoir trend. 79 The absence of a trend between porosity and permeability with depth of burial is related to the lithology and diagenesis of Doig sand bodies. Reservoir sandstones at Stoddart/Cache Creek and Buick Creek have primary porosity preserved from compaction effects by early calcite cementation. The subsequent dissolution of calcite and quartz cements re-opened inter-granular porosity and formed additional secondary porosity. In non-productive Doig sand bodies, either the calcite cement did not undergo dissolution (Fireweed) or an absence of early calcite allowed porosity destruction through mechanical and chemical compaction (Kilkerran, Groundbirch) and consequently inhibited the formation of secondary porosity. The presence of bioclastic material both reduces and enhances reservoir quality: bioclastic material is a source for early calcite cement and bioclastic rocks act as a reservoir facies. Walderhaug and Bjorkum (1998) report that the distribution of biogenic carbonate is the source and the control on geometry of early calcite cements in shallow marine sandstones of the Norwegian shelf. In Doig cores, calcite cemented layers and concretions are often associated with bioclastic debris. Walderhaug and Bjorkum's (1998) study also implies that the distribution of bioclastic carbonate in Doig sand bodies controls the distribution of early calcite cement which in turn acts as a control on the distribution of secondary porosity. A study by Molenaar (1998) of the Luxemburg sandstone further suggests that early marine calcite cements form lenses that are laterally controlled by the original sedimentary structures formed by storm-built ridges, tidal delta lobes, dune foresets and channel lags. The calcite lenses in the Luxemburg sandstone are discontinuous with lateral extents up to several tens of metres. The distribution of early calcite layers in Doig sandbodies by similar factors suggests that calcite cemented intervals in Doig sand bodies may also be laterally discontinuous. The 80 capacity of bioclastic beds to act as a reservoir lithology is related to fracture controlled dissolution. Abundant fractures at West Stoddart and Cache Creek, a consequence of burial and pervasive early calcite cements, enhance the permeability and porosity of the coquina lithofacies (Fig. 12b). The most extensively developed secondary porosity is developed in the West Stoddart and Cache Creek fields. The enhanced permeability created by the fracture network allowed for increased dissolution of bioclasts and interstitial and replacement cements, creating or enlarging secondary pores. Production in sandbodies along the reservoir trend is a function of depositional environment, lithology, diagenesis, sand body geometry and orientation of the wellbore. Rapid production declines at West Stoddart and Cache Creek is an example of this interaction. Deposition of sandbodies at West Stoddart and Cache Creek as distributary channel fills results in relatively small, compartmentalized sandbodies of significantly lower volume than sand bodies in other areas along the Doig trend. The deposition of abundant carbonate bioclasts within these sand bodies provides a source of pore occluding early calcite that significantly preserved inter-granular porosity. Early cements and perhaps tectonic factors contributed to the formation of fractures and faults, enhancing the permeability and allowing for the dissolution of framework grains and cements to form secondary pore networks. The high relative permeability of sandstones at West Stoddart and Cache Creek (Table 2) result in higher and more consistent decline rates than those observed in the higher porosity and lower permeability sandstone at Buick Creek. The constant decline rate for production in the West Stoddart and Cache Creek reservoirs (Fig. 13a) suggests that the fracturing of these reservoirs has enhanced permeability to fluid flow between wells. 81 In general, horizontal wells produce, as anticipated, at significantly higher rates than vertical wells. The reverse occurs at the Fireweed and Valhalla fields however, where a scarcity of data prevents a meaningful comparison between deviated and non-deviated wells. The highest average daily production rates for deviated and non-deviated gas wells are achieved in the Sinclair field. The absence of a liquid hydrocarbon phase at Sinclair significantly increases the relative permeability of this reservoir to gas (Levorsen, 1967). The lowest average daily production values for oil and gas are observed for the Fireweed field. The lack of secondary porosity generation and removal of inter-granular calcite cement in a significant proportion of Fireweed wells results in lower overall average production rates, although individual wells achieve much higher production rates. 3.10. - Constraints on Exploration The risk of exploration for Doig sandbodies can be reduced by constraints provided by stratigraphy, diagenesis, structure, sedimentology, basin modeling, and core analysis and production data. Constraints can be mapped onto the regional Doig reservoir trend (Fig. 15) in order to delineate an exploration fairway. The fairway is bounded to the west by a stratigraphic pinch-out of the reservoir facies, and to the east and north by thinning of the Doig Formation and erosion by the overlying Halfway shoreface. Underlying faulted slope breaks structurally controls the position of the Doig shoreline trend (Harris and Bustin, submitted). The depth of the sand body trend is controlled by burial and tilting produced by subsidence and extensional tectonics related to the Dawson Creek Graben and sediment loading related to Laramide tectonism. The 82 R N G E 13 11 09 07 LEGEND ** ^ ** Stratigraphic Pinchout J B ** KJ Doig Sandstone Bodies Local Erosion & Thinning ^ Base of Oil Window \ v j Trend of Increasing /f>\ Dolomite & Anhydrite v/J Cement > ^ Gas Prone Reservoirs - Overmature -S C A L E Kms 20 40 60 Fig. 3.15 - Exploration fairway map for Doig sand bodies in the Peace River area. Gas-prone exploration area reflects the extension of the reservoir trend below the oil window. 83 source for numerous Triassic hydrocarbon accumulations is the Phosphate Zone at the base of the Doig Formation (Riediger et al., 1990). Thermal maturity data from Bustin (1999) allows the base of the oil window in Nordegg time (Tmax = 465°C from Rock Eval pyrolisis) to be overlayed onto the reservoir trend (Fig. 15). The Nordegg formation lies 250 metres above the reservoir unit in the study area and is used to approximate the base of the oil window for Doig reservoirs. The base of the oil window separates the Doig trend into oil and gas prone reservoirs in the northwest and gas prone reservoirs in the southeast. Evidence to support the maturity data is observed at the Valhalla and Sinclair fields of Alberta. The two fields are 25 kilometres apart and lie on either side of the base of the oil window. The Sinclair field is an abundant producer of gas and the Valhalla field is a moderate producer of oil and gas. The economics of oil and gas production will direct the decision to explore to the south or north of the base of the oil window. Two final factors to consider are the distribution of open fractures and cements. Abundant open fractures occur in the West Stoddart and Cache Creek fields only. The distribution of fractures is associated with the distribution of early calcite cements. The distribution of calcite cements is, in turn, controlled by the distribution of bioclastic material related to the original depositional environment. The disposition of bioclastic material can be predicted through the development of facies models for individual reservoirs. The control on bioclastic material distribution along the regional reservoir trend is unknown and therefore cannot be used to constrain exploration. The increasing abundance of dolomite and anhydrite cement in Doig reservoirs in a southeastward direction along the reservoir trend is predictable (Fig. 15) although not well understood. The impact of this cement trend on reservoir quality and production is beyond the scope of this study and would be useful theme for future work. 84 3.11. - CONCLUSIONS Doig sand bodies in northeastern British Columbia and west Central Alberta consist of clean sandstones and bivalve coquinas deposited as part of a regressive shoreface during the Middle Triassic. The sandstones are sub-lithic to quartz arenites with varying amounts of detrital dolomite, apatite, calcite and microcline. The coquinas are well to poorly sorted sub-imbricate bivalve wackestones to packstones. Diagenetic constituents in order of abundance are calcite, quartz, apatite, dolomite, anhydrite and pyrite. Open porosity is essentially secondary inter-granular, vuggy and moldic, with varying amounts of primary inter-granular and fracture porosity. Early diagenesis includes the formation of calcite concretions and layers, mechanical compaction and fracturing, and the dissolution of bioclasts to form moldic and vuggy porosity. Late diagenesis included further compaction and the formation of authigenic quartz, quartz dissolution and replacement by carbonate, precipitation of ferroan calcite filling open porosity, dissolution of framework grains and cements to form secondary porosity, precipitation of anhydrite and dolomite, and finally charging of the reservoirs with hydrocarbons. Lithology and diagenesis control the distribution of effective porosity and permeability and thus hydrocarbon production across the reservoir trend. The distribution of early calcite sourced from bioclastic material is a critical factor in the preservation of primary porosity from the irreversible destructive effects of compaction and for the formation of open fractures. Dissolution of early calcite and framework quartz to form secondary inter-granular porosity is responsible for much of the effective porosity in Doig 85 reservoirs. Augmentation of dissolution by fracturing associated with burial is critical in the formation of secondary porosity and increasing permeability in both the sandstone and coquina lithofacies. Enhancement of effective porosity and permeability through fracturing and dissolution provide the controls on reservoir development and guide exploration for Doig sand bodies along the reservoir trend. 3.12. - REFERENCES CITED Adams, A.E., MacKenzie, W.S., and Guilford, C , 1984. Atlas of sedimentary rocks under the microscope. Wiley & Sons, New York, p. 104. Berner, R.A., 1981. A new geochemical classification of sedimentary environments. Journal of Sedimentary Petrology, v.51, pp.359-365. Berner, R.A., 1984. Sedimentary pyrite formation: an update. Geochim. Cosmochim. Acta, v.48, pp.605-615. Bustin, R.M., 1999. Organic maturity in the Peace River Arch area of the Western Canada Sedimentary Basin (poster). Canadian Society of Petroleum Geologists Convention, Calgary, Alberta. Curtis, CD., 1978. Possible links between sandstone diagenesis and depth-related geochemical reactions occurring in enclosing mudstones, Geological Society of London Journal, v135, pt.1, pp.107-117. Dickson, J.A.D., (1965). A modified staining technique for carbonates in thin section. Nature, v.205, p.587. Dunham, R.J., 1962. Classification of carbonate rocks according to depositional texture, in W.E. Ham, edit., Classification of Carbonate Rocks. Memoir of the American Association of Petroleum Geologists, v. 1,pp. 108-121. Dypvik, H., 1983. Clay mineral transformations in Tertiary and Mesozoic sediments of the North Sea. Bulletin of the American Association of Petroleum Geologists, v.67, pp.160-165. Evoy, R.W. and Moslow, T.F., 1995. Lithofacies associations and depositional environments in the Middle Triassic Doig Formation, Buick Creek Field, northeastern British Columbia. Bulletin of Canadian Petroleum Geologists, v43, p. 461-475. 86 Evoy, R.W., 1997. Lowstand shorefaces in the Middle Triassic Doig Formation: implications for hydrocarbon exploration in the Fort St. John area, northeastern British Columbia. Bulletin of Canadian Petroleum Geologists, v45, p537-552. Gibson, D.W. and Edwards, D.E. 1990. An overview of Triassic stratigraphy and depositional environments in the Rocky Mountain Foothills and Western Interior Plains, Peace River Arch. S.C. O'Connell and J.S. Bell (eds.). Bulletin of Canadian Petroleum Geology, v.38, p. 146-158. Hayes, J.B., 1979. Sandstone Diagenesis - The Hole Truth, in P.A. Scholle and P.R. Schluger, edits., Aspects of Diagenisis. Special Publication of the Society of Economic Paleontologists and Mineralogists, no.26, pp.127-139. Hesse, R. and Abid, L.A., 1998. Carbonate cementation-the key to reservoir properties of four sandstone levels (Cretaceous) in the Hibernia Oilfield, Jeanne d'Arc Basin, Newfoundland, Canada, in S. Morad, edit., Carbonate Cementation in Sandstones. Special publication of the International Association of Sedimentologists, no. 26, pp.363-393. Hsu, K.J., 1977. Studies of Ventura Field, California, II: Lithology, Compaction, and Permeability of Sands. The American Association of Petroleum Geologists, Bulletin, v.61, pp.169-292. Galloway, W.E., 1974. Depositional and diagenetic alteration of sandstone in Northeast Pacific arc-related basins: Implications for graywacke genesis. Geological Society of America, Bulletin, v.85,pp.379-390. Jonas, E.C. and Mcbride, E.F., 1977. Diagenesis of sandstones and Shale: Application to Exploration for Hydrocarbons: Continuing Education Program Publication 1, The University of Austin at Texas, p. 165. Levorsen, A.L, 1967. Geology of Petroleum. W.H. Freeman and Comapany, San Fransisco, pp.724. McBride, E.F., 1963. A classification of common sandstones. Journal of Sedimentary Petrology, v.34, p.667. Meckel L.D., 1975. Holocene sand bodies in the Colorado Delta area, northern Gulf of California, in M.L. Broussard, edit. Deltas. Houston Geological Society, p87-98. Molenaar, N., 1998. Origin of low-permeability calcite-cemented lenses in shallow marine sandstones and CaC03 cementation mechanisms: an example from the Lower Jurassic Luxemburg Sandstone, Luxemburg, in S. Morad, edit., Carbonate Cementation in Sandstones. Special publication of the International Association of Sedimentologists, No. 26, pp.179-192. Pearson, M.J., Watkins, D., Pittion, J.L., Caston, D., and Small, J.S., 1983. Diagenesis, organic maturation and paleothermal history of an area in the South Viking Graben, 87 North Sea. in J . Brooks, edit., Petroleum Geochemistry and Exploration of Europe. Special Publication of the Geological Society of London, v. 12, pp. 161-174. Riediger, C.L., Fowler, M.G., Brooks, P.W. and Snowdon, L.R., 1990. Triassic oils and potential Mesozoic source rocks, Peace River Arch are, Western Canada Basin. Organic Geochemistry, v. 16, p.295-305. Schmidt, V. and McDonald, D.A., 1979. The role of secondary porosity in the course of sandstone diagenesis. in P.A. Scholle and P.R. Schluger, edits., Aspects of Diagenesis. Special publication of the S E P M , no. 26, pp.175-207. Selley, R . C , 1978. Porosity gradients in North Sea oil-bearing sandstones. Geological Society of London, Journal, v.135, pp.119-132. De Sousa, R.S. and De Assis Silva, C M . , 1998. Origin and timing of carbonate cementation of the Namorado Sandstone (Cretaceous), Albacora Field, Brazil: implications for oil recovery, in S. Morad, edit., Carbonate Cementation in Sandstones. Special publication of the International Association of Sedimentologists, no. 26, pp.309-325. Taylor, J .M. , 1950. Pore-space reduction in sandstones. American Association of Petroleum Geologists, Bulletin, v.34, pp.701-716. Tucker, M.E. and Wright, P.V., 1990. Carbonate Sedimentology, Blackwell Scientific Publication, London, pp 482. Walderhaug, O. and Bjorkum, P.A., 1998. Calcite cement in shallow marine sandstones: growth mechanisms and geometry, in S. Morad, edit., Carbonate Cementation in Sandstones. Special publication of the International Association of Sedimentologists, No. 26, pp. 179-192. Wilson, J . C and McBride, E.F., 1988. Compaction and Porosity evolution of Pliocene sandstones, Ventura Basin, California. American Association of Petroleum Geologists, Bulletin, v.72, pp. 662-674. Wittenberg, J . , 1992. Origin and stratigraphic significance of anomalously thick sandstone trends in the Middle Triassic Doig Formation of west-central Alberta. Unpublished M.Sc. thesis, University of Alberta, Edmonton, Alberta. 600p. 88 CHAPTER 4 Conclusions The ultimate control on reservoir quality and production of sand bodies along the Doig Formation reservoir trend is deposition. The distribution of bioclastic carbonate and calcareous mudstone rip-up clasts act as a source for early calcite cement. The distribution of early calcite cement acts to preserve primary inter-granular porosity and influence the formation of fracture networks. The formation of secondary porosity is enhanced during burial diagenesis by permeability created by earlier fracturing. Underlying extensional faults act as a control over the position and orientation of the sand trend and syn-sedimentary faulting and slumping is locally responsible for isolated sand accumulations. Thick sand bodies of the Doig Formation in northeastern British Columbia are deltaic and inter-deltaic shallow marine sands deposited during a regression of the Doig shoreface into the study area. The sandstones are sub-lithic to quartz arenites with varying amounts of detrital dolomite, apatite, calcite and microcline. The coquinas are well to poorly sorted sub-imbricate bivalve wackestones to packstones. Diagenetic constituents in order of abundance are calcite, quartz, apatite, dolomite, anhydrite and pyrite. Open porosity is secondary inter-granular, vuggy and moldic, with varying amounts of primary inter-granular and fracture porosity. Early diagenesis includes the formation of calcite concretions and layers, mechanical compaction and fracturing, and the dissolution of bioclasts to form moldic and vuggy porosity. Late diagenesis included further compaction and the formation of authigenic 89 quartz, quartz dissolution and replacement by carbonate, precipitation of ferroan calcite filling open porosity, dissolution of framework grains and cements to form secondary porosity, precipitation of anhydrite and dolomite, and finally charging of the reservoirs with hydrocarbons. Enhancement of effective porosity and permeability through fracturing and dissolution provide the controls on reservoir development and guide exploration for Doig sand bodies along the reservoir trend. Results from this investigation further constrain the depositional environment, and outline the paragenetic sequence for Doig sandbodies in northeastern British Columbia. The wide scope of this investigation leaves many possibilities for future work. The paragenetic sequence requires further geochemical constraint. The transition from calcite to dolomite and anhydrite cements down dip along the reservoir trend is not understood. The dissolution and replacement of quartz by calcite is reported but not adequately explained. Additional investigations of sedimentology of Doig sand bodies lying along the reservoir trend between our field area and producing sand bodies in west central Alberta should be integrated with this and other studies in order to better understand the regional depositional setting. 90 APPENDICES Appendix A - Core Identification and Location Appendix B - Core Descriptions Appendix C - Catalogue of Thin Sections Appendix D - Core Analysis Data 91 APPENDIX A Core Identification and Location License Well ID Field Interval Analysis # 10019 b-21-L/94-G-9 Tommy Lakes Doig NA 1 5132 d-73-F/94-G-9 Tommy Lakes Doig Y 2 5113 d-91-G/94-G-9 Tommy Lakes Doig Y 3 8724 d-39-E/94-A-14 Buick Creek Doig Y 4 7479 09 34 88 20W6 Buick Creek Doig Y 5 7200 d-86-l/94-A-11 Buick Creek Doig Y 6 4622 d-45-l/94-A-11 Buick Creek Doig NA 7 7679 d-35-A/94-A-14 Buick Creek Doig Y 8 4172 d-46-l/94-A-11 Buick Creek Doig Y 9 3973 2/d-57-l/94-A-11 Buick Creek Doig Y 10 3996 d-58-l/94-A-11 Buick Creek Doig Y 11 3992 d-68-l/94-A-11 Buick Creek Doig Y 12 6872 b-77-l/94-A-11/2 Buick Creek Doig Y 13 7623 d-76-l/94-A-11 Buick Creek Doig Y 14 7520 2/d-96-l/94-A-11 Buick Creek Doig Y 15 7538 d-6-A/94-A-14 Buick Creek Doig Y 16 7438 a-29-K/94-A-10 Buick Creek Doig Y 17 10581 01 07 85 15W6 Unknwn-Rigel Doig NA 18 9621 a-66-l/94-A-10 Rigel Doig Y 19 9851 15 21 87 20W6 Fireweed Doig Y 20 4369 b-26-D/94-A-14 Fireweed Doig Y 21 4454 b-6-D/94-A-14 Fireweed Doig Y 22 7716 d-42-H/94-A-13 Fireweed Doig Y 23 4530 C-80-L/94-A-11 Cache Creek Doig Y 24 10155 12 35 87 22W6 Cache Creek Doig Y 25 4914 b-64-l/94-A-12/2 Cache Creek Doig Y 26 10012 04 03 88 22W6 Cache Creek Doig Y 27 6856 06 07 79 20W6 Groundbirch Doig Y 28 7175 10 13 79 21W6 Groundbirch Doig Y 29 9970 04 29 83 18W6 Ft. St. John Doig Y 30 5020 16 34 82 16W6 Two Rivers Doig Y 31 5684 12 01 78 14W6 Kilkerran Doig Y 32 92 License Well ID Field Interval Analysis # 7469 Scott Doig Y 33 9890 01 05 88 21W6 W.Stoddard Doig Y 34 9972 14 31 87 21W6 W.Stoddard Doig NA 35 9971 11 29 87 21W6 W.Stoddard Doig Y 36 10582 10 36 87 22W6 W.Stoddard Doig Y 37 6693 2/06 04 86 20W6 W.Stoddard Doig Y 38 APPENDIX B Core Descriptions Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. 01-05-88-21W6 West Stoddart Scale 1:50 Metric #9890 1 DOIG From: 1650 Cut: To : 1658 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 Lithology Geological Descriptions o q ~ Porosity (*/•) Qulii Oiiu (nun) Facies 2c : X-bedded fg-mg qtz sandstone, intervals of missing core Facies 2c/2g : x-bedded poorly sorted vfg-fg qtz sandstone + abundant mudstone interclasts + minor fossil debris Facies 2g : sediment starved compacted mudstone lag 95 Porosity (%) Gram Size (mm) 3 Facies 2c : coarsening up lower/middle shoreface bedded sandstone Facies 2g : sediment starved mudstone Facies 1a : laminated mudstone = channel abandonment. Facies 2b/2g : Poorly sorted massive sandstone + mudstone interclasts = channel lag. Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. 2/06-04-86-20-W6 West Stoddart Scale 1:50 Metric #6693 1 DOIG From: 1596.5 To: 1614.8 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 GR (units) Sonic (units) Lithology Geological Descriptions Porosity (%) Grain Size (mm) Porosity (%) Grain Size (mm) -Facies 1c : Laminated to very finely bedded siltstone, mudstone and vfg ss. Horizontal laminae, abundant flame structures. Shelf/shoreface transition, below storm wave base Abrupt contact FACIES 1C/2A : 3 coarsening up cycles of laminated siltsone to laminated ss. Appear as progradational cycles of tidal dominated lower shoreface deposit. ?Prodelta? 97 FACIES 1c : laminated siltstone with vfg ss, abundent rounded mudstone interclasts, absence of bioturbation. Coarsening up FACIES 2b : fining-up vfg-fg qtz ss, basal lag of bioclastic debris FACIES 2b : fining-up vfg-fg qtz ss, basal lag of bioclastic debris FACIES 2b : weakly bedded to massive vfg-fg qtz ss, sparse convolute thin mudstone laminae. Evidence of soft sed. deformation, rare bioturbation (?Ophiomorpha), rare zones of fossil debris (? slump deposit?) GR (units) -Sonic (units) Abrupt contact. Eroslonal? FACIES 1a : Laminated mudstone FACIES 1c : laminated siltstone/mudstone with vfg sandstone, fining upward gradatlonal contact FACIES 2a : Laminated sandstone and mudstone FACIES 1c : Laminated siltstone with vfg ss Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 10-36-87-22-W6 West Stoddart #10582 DOIG From: 1599.5 Cut: To : 1605.6 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology TG, C1-C5 GR (units) Sonic (units) Geological Descriptions GR (units) Porosity (%) Grain Size (mm) -Porosity (%) Grain S izr (mm) -Facies 0/7 : weakly convolutely laminated to massive fg quartz ss, concretions, rare fossil debris, coarsening up Facies 2a : wavy laminated fg qtz ss and mudstone, coarsening up - PROGRADING DELTA FRONT Facies 1a: laminated mudstone -SHELF {ionic (unit^l 1*0 GR (units) 1*0 100( 100( 100t 1001 99 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 14-31-87-21W6 West Stoddart 1 DOIG From: 1627 To: 1644 #9972 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 GR (units) Sonic (units) Lithology Geological Descriptions . a :K a 1 o ' a n. 1 1 1- -1 C B (unite) ) 1 Sonic (units 3 1' 0 100( 0 10CK : 1 1 1 1 GR (units) 3 1 ionic (units 3 1 IO 100C IO 1000 • - -: . , - •• ~ Porosity {%) Grain Size (mm) I Porosity I'yiJ | Gram Stze (mm) "561 FACIES 2f/2e : massive qtz ss + fractured concretionary coquina, dissolution features, fractured, abundant moldic and vuggy porosity FACIES 2c : hz laminated vfg-fg qtz ss, calcite cement zones towards upper contact, large open vertical fractures FACIES 1a : laminated mudstone, channel - abandonment FACIES 2c : x-bedded qtz ss, sand filled ; vertical fractures, abundant concretions FACIES 2e : x-bedded vuggy coquina and fg qtz ss, abundant small sub-vertical fractures 100 Porosity (%) train Size ^ mm)" FACIES 2c : x-bedded qtz ss and coquina, coquina intervals both fining and coarsening up, abundant concretions and fractures, gradational contacts FACIES 2f : x-bedded imbricate vuggy coquina, continuous energy regime, no break FACIES 2e : as below, abundant open and partially filled fractures and vugs FACIES 2f : massive eg coquina, basal lag, rare large vugs FACIES 2e : x-bedded qtz ss and coquina, coquina intervals both fining and coarsening up FACIES 2c : x-bedded fg qtz ss, abundant tabular concretions/breccia, abundant fractures FACIES 2f : basal coquina lag, highly abraded, abundant vuggy porosity FACIES 2e/2f : lo-angle x-bedded fg-mg qz ss & coquina, abundant concretions & thicker coquina horizons, abundant vertical sand-filled fractures - -- -. . . - -i — 1 1 1 GR (units) 3 1 Sonic (units ) 1 lO 1001 -10 100C • - -101 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 01-05-88-21W6 West Stoddart 2 DOIG From: 1661 To: 1667.2 #9890 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) — Grain Size (mm) -Lithology Geological Descriptions TG, C1-C5 Porosity (%) Quil 3lie(iilill) FACIES 2e : x-bedded vfg-fg qtz ss and coquina interclasts, patchy calcite cement, moldic and inter-granular porosity, filled sub-vertical fractures FACIES 2f : abraded x-bedded bivlave coquina and qtz ss, coquina appears as large clasts (perhaps rip-ups) FACIES 2c/2g : x-bedded fg qtz ss and mudstone rip-ups, lo-angle planar x-beds, rip-ups are tabular and follow bedding, abundant calcite cement and fossil debris FACIES 2c : x-bedded vfg-fg qtz ss, lo-angle, planar x-beds, moderately sorted, abundant fossil debris and mudstone interclasts, ophiomorpha traces, patchy calcite cement FACIES 2g : poorly sorted fg-mg qtz ss, eg pyrite and mudstone intrerclasts, abundant fossil debris and muddy intervals, ophiomorpha traces FACIES 2b : massive vfg-fg qtz ss, patchy calcite cement FACIES 2a : convoiutely laminated vfg qtz ss and mudstone, bioturbated?? deformed, rare pyrite and fractures , abundant calcite cement 102 C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: 11-29-87-21W6 West Stoddart #9971 1 DOIG From: 1659 Cut: To : 1677 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology TG, C1-C5 GR (units) Sonic (units) Geological Descriptions FACIES 2f : x-bedded coquina, as below FACIES 2e : x-bedded qtz ss/coquina FACIES 2f : x-bedded abraded coquina, lithic interclasts, abundant moldic/vuggy porosity FACIES 2c : x-bedded qtz ss Abrupt/erosional (anydrite?) FACIES 2c : X-bedded fg qtz ss FILL • CHANNEL GR (units) 1 1 1 • 1 1 11 ionic (unit! D 11 ) o iooc 1 1 1 " " " 1 GR (units) 0 V ionic (unit: 0 1i 0 100t ) -0 100( 103 I Porosity (%) Grain Size (mm) -Abrupt contact FACIES 2e : x-bedded qtz ss/coq CHANNEL FILL FACIES 2c : x-bedded fg qtz ss FACIES 2a : x-bedded vfg qtz ss, abundant mudstone stringers MISSING CORE 1 . _ _ 1 1 1 1 GR (units) 0 11 ionic (unit! 0 1i 0 100C ) 0 100C : • • : _ _ .. „ -104 C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: 12-35-87-22-W6 Cache Creek 1 ,2 ,3 DOIG From: 1655 To: 1675.2 #10155 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology TG, C1-C5 GR (units) Sonic (units) .11 Geological Descriptions G R (units) 1 1 1 1 onic (unit! » Ii ) 0 100C . . . - . • •• ~ • - " -1 .1 1 ; i G R (units) S 1 ionic (unit! a 1 1 0 100C ) . 0 100C Facies 2e : Inter-bedded qtz ss/coquina, highly abraded,mudstone intraclasts, fractured, abundant inter-granulzr and moldic pores - CHANNEL FILL Facies 2g: as below Facies 2c: as below Facies 2f : coquina highly abraded, fractured, moldic porosity Facies 2c: laminated-bedded fg qtz ss 30cm of blocky blck mudstone Facies 2c : Hz bedded qtz ss Missing Core Facies 2a : Laminated/bioturbated sanstone/mudstone in a series of coarsening up packages - LOWER 105 o . o 6 °o' °. Abrupt, pyritized - condensed? Facies 1a : Convolute siltstone/mudstone, soft sed. deformation Facies 2b/2c/2g : massive to hz bedded ss, mudstone and mudstone interclast lag Erosive, either TSE or channel abandonment Facies 2c : vfg-fg low-angle x-bedded qtz ss, concretions, fractures -CHANNEL FILL? Facies 10 : Interbedded qtz ss/coquina, highly abraded, mudstone rip ups, early fractures - CHANNEL FILL Facies 2f: Weakly bedded coquina, highly abraded, vuggy and moldic pores Facies 2e : Interbedded qtz ss/coquina, highly abraded, intergranular and moldic pores, abundant mudstone interclasts -CHANNEL FILL • • - -1-- • -1 . . . . . . . 1 1 GR (units) 1 1 ionic (unit! a 1 0 100( ) 0 1001 • •• " -- - - - - - - - - •• . .. I I 106 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 04-03-88-22W6 Cache Creek DOIG From: 1692 Cut: T o : 1708.5 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C 1 - C 5 GR (units) Sonic (units) 'JL 2-Lithology Geological Descriptions a !c » ,o a a. V §«> O i O = •V) :K O Porosity (%) flialil3u.il (mill) J . I I I FACIES 2c : planar - wavy laminated fg ss, bioturbated, abundant mudstone intervals/interciasts gradational FACIES 2a : x-laminated fg ss/mudstone abrupt contact - channel abandonment? GR (units) 1 1 >onic (unit! D 11 ) 0 100< — __- r . . . .. 107 FACIES 2c : lo-angle, planar x-bedd fg-mg qtz ss .occaisional massive intervals-CHANNEL FILL GR (units) 1 feonic (units)) 1*0 •0 100( 100( abrupt contact FACIES 2c : lo-angle bedded fg ss aprupt contact • erosional FACIES 1a : laminated-massive mudstone, deformation at upper contact - SHELF abrupt contact FACIES 1c : mottled siltstone/vfg ss, bioturbated? SHELF Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. D-64-I/94-A-12/2 Cache Creek Scale 1:50 Metric #4914 1 DOIG From: 1696 To: 1713.9 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 GR (units) Sonic (units) Lithology a. E a* o Q a. Geological Descriptions Porosity (%) Si all i sue (mm) 3s Porosity (%) Grain Size (mm) -p ~ - i - i - r T i - i -T-i-rp. FACIES 2c : HCS(?), x-bedded fg-qtz ss, tidal couplet mud drapes, no trace fossils/body fossils - UPPER SHOREFACE abrupt hi-angle erosional contact FACIES 2b : ripple laminated - massive vfg-fg qtz ss, abundant lithic, mudstone abrupt contact? FACIES 1c : convolute laminated siltstone/vfg ss, bioturbated, abundant micropyrite abrupt contact - bored hardground ? FACIES 1c : siltone/vfg ss laminae • bioturbated? GR (units) 1""" 1 ionic (unit; D 1< ) 0 100( . . . • -- - •• 1 1 J 1 '1 GR (units) J 1 ionic (unit: a 1 0 10W ) 0 100C 109 is Porosity (%) Qraln Size (mm) - Ibl r M v - i c o ia : massive to weaniy laminaiea silty mudstone, no visible trace fossils, rare body fossils - SHELF FACIES 1a : massive to weakly laminated silty mudstone, no visible trace fossils, rare body fossils - SHELF - pyritized, weakly laminated wt vfg ss abrupt contact FACIES 1c : laminated siltstone, mudstone & vfg ss - SHELF . — - -1- - - -1 i" ~"'"" 1 GR (units) ) - M ionic (unit: a 1i 0 -tow ) . . . 0 100< , -. _ : — : 110 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric C-80-U94-A-11 #4530 Cache Creek (Fireweed) 4 DOIG From: 1606 To: 1624.5 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534^ Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 GR (units) Sonic (units) Lithology Geological Descriptions Grain Size (mm) 1? Porosity (%) Grain Size (mm) -~m •r FACIES 2c/1a : Generally fining up intebedded and laminated mudstone & vfg qtz ss. ss interbeds have erosive bases and fine upwards (TUBIDITES). ss intervals are bioturbated and are not present in upper 3m of interval, abundant micropyrite in upper 6m {Sonic (unit: 1*0 *o GR (units) Isonic (unit: 100C 100( 1^ 0 10(K 100( 111 U L . Porosity (%) Grain Size (mm) - - 1, \p---z-z-z-\ abrupt contact FACIES 2f : massive fossil debris coq, whole and abraded bioclast, vfg qtz ss matrix - MASS FLOW abrupt pyritized contact FACIES 2c : laminated vfg ss with fossil debris lenses, bioturbated • MASS FLOW abrupt contact, cut & fill FACIES 1c : laminated mudstone/siltstone abrupt contact • TS? FACIES 2f : massive coquina/ vfg ss gradational contact FACIES 2f: brachiopod/bivlave/echinoderm coquina, matrix = vfg qtz ss, convolute to weakly laminated mudstone. bioclasts are generally delicate and moderatly to unabraded. masive,disorganized texture -MASS WASTING - SLUMP DEPOSIT abrupt, loading structures FACIES 2b : massive - weakly laminated vfg qtz ss, abundant scatterd fossil debris (isolated & lenses) abrupt contact FACIES 2a : laminated vfg qtz ss & mudstone, weakly bioturbated -SHOREFACE TRANSITION . . . • - • • • • .. . .. 1 - - — 1 1 1 GR (units) ) • - 1i ionic (unit: J 1i 0 10CH ) 0 1001 . . . . . . . - - • r 112 Well Name: Location: Contractor: Core #: Formation: Core interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 04-29-83-18-W6 Ft. St. J o h n 1,2 DOIG From: 1509 To: 1528.4 #9970 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) S Perotlty (iZ^ Grain Size (mm) FACIES 2e : x-bedded vfg-fg qtz arenite and coquina, lo-angle planar x-beds, highly abraded moldic coquina, pebble sized mudstone and pyrite interclasts, increasing fossil debris toward core top FACIES 2c: horizontally x-laminated/bedded vfg qtz ss (10% lithic grains), calcite concretions, calcite filled vertical fractures, rare traces, calcite cements increase towards upper contact, mudstone interclasts and fg bioclastic debris appear toward upper contact FACIES 1c/2b : convolutely interbedded muddy siltstone and vfg qtz ss, coarsening 1 1 1 - 1 CB (units) 0 1i ionic (unit! D * 0 100( ) 0 10W 1 1 1 1 GR (units) 0 - 1i ionic (unit! ) 1i 0 10M ) 0 100C - - - - - - -_ 113 • • • T V . 15 . . - r : Porosity (•/.) Grain Size (mm)' m CO J«M to JCM to 0> JCM filled vertical fractures, rare trace fossils, ripples, calcareous and visible calcite cements FACIES 1c/2b : convolutely interbedd muddy siltstone and vfg qtz ss, coarsening up, abundant calcite concretions, calcite filled vertical fractures, rare trace fossils, ripples, calcareous and visible calcite cements FACIES 1c : mottled to convolutely laminated muddy siltstones and vfg qtz ss, abundant soft sed. deformation, calcareous, filled vertical fractures - • • -. . . 1 1 1 1 GR (units) D 1' ionic (unit! ) 1i 0 100( ) 0 100C - - - • • - - - - - - - •• - • - • - • •• • - -114 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. 1-7-85-15-W6 Rigel Scale 1:50 Metric #10581 Halfway/DOIG From: 1476 Cut: To: 1486 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology TG, C1-C5 GR (units) Sonic (units) t = « w a. o Geological Descriptions Porosity (14) Grain Size (mm) 1? FACIES 2c : laminated vfg qtz ss, It brown, planar-convolute laminae, abundant traces (abundance & variety), mudstone intervals, occaisional fg bioclastic intervals, non-calcareous -PROXIMAL SHELF abrupt, marked by lag of rounded fg bioclasts FACIES 1b : light grey coquina, siltstone matrix, abundant mudstone stringers, abundant vfg It brown qtz ss interbeds (event deposits?), bioclasts include whole and abraded pelecypod, brachiopod, echinoid & bryozoan, overall texture consists of fining-up packages with random internal organization •* j>onic (units) 1*0 1*0 100( 100< 115 Porosity (%) Grain Size (mm)- 1 : FACIES 1c : weakly laminated - massive siltstone, occaisional grey vfg qtz ss interbeds, abundant bioclasts (whole and abraded pelecypod, brachiopod, horizontally aligned), rare traces towards upper contact - DISTAL SHELF FACIES 1 1 1 1 GR (units) ) 11 ionic (unit! D 1i 0 10« ) 0 100C - - -116 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. a-66-l/94-A-Rigel 10 Scale 1:50 Metric #9621 Halfway/DOIG From: 1333 Cut: To : 1345.3 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) 1 1 - - • - -GB (units) 0 1' Sonic (unit! 0 -11 0 100( ) 0 100( . . . . . . - - - - - -_ .. .. _ . . . — - - - - - -. — — . . . . - • -i s . -5--mottled buff dolomite/calcite, abundant intraclasts abrupt, HALFWAY/CHARLIE LAKE contact marked by laminated dolomite & dessication cracks FACIES 2c : laminated fg-mg qtz ss (sub-arkose), lo-angle planar laminae, x-laminated towards upper contact, abundant bitumen staining, single 20cm coquina interval (abraded pelecypod, brachiopod, visible open moldic porosity), occlusion of open porosity by calcite increases towards upper contact -UPPER SHOREFACE/FORESHORE abrupt? FACIES 2c : laminated fg-mg qtz ss, planar Hz laminae, no visible calcite, weak Rx, no traces/body fossils abrupt, possible DOIG/HALFWAY contact marked by abrupt coarsening and absence of calcite cement 117 I Pclosity (%) 'Grail Size (mrr IT 20; 1 9 1 1 m FACIES 2c : laminated fg qtz ss, lo-angle-Hz planar laminae, occaisional disruption by water escape structures, abundant visible calcite spar, no traces/body fossils 1 1 1 1 GR (units) D 1i ionic (unit! 0 1i 0 100c ) 0 100c • - - - -— - -118 C O R E STRIP LOG WellSight Systems Inc. Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: D-6-D/94-A-14 Fireweed 1 DOIG From: 1643.9 To: 1659.5 Scale 1:50 Metric #4454 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 GR (units) Sonic (units) Lithology Geological Descriptions FACIES 2c : Laminated fg-mg qtz sandstone, planar lo-angle laminae, abundant concretions, fossil debris horizons, mudstone intraclasts, sub-horizontal fractures (calcite), poor -good intergranular porosity gradatlonal contact FACIES 2b : massive fg qtz ss, abundant lensed of massive poorly sorted coquina. good intergranular porosity (14%0 abrupt contact Facies 2c : Laminated - massive vfg-fg qtz ss, mod-angle planar laminae. abrupt contact FACIES 2b : Massive to convolutely laminated qtz ss gradatlonal contact FACIES 2a : convolute laminated mudstone/vfg qtz ss abrupt contact, pyrttlzed, fossil debris FACIES 1a : weakly laminated biack-brown calcareous mudstone, lo-angle planar laminae, scattered fossil debris. GR (units) 1 1 i " i 1 1 ionic (unit! 0 11 ) 0 100( - - - •• -.. . .. _ -• - - '--1 .1 1 -i GR (units) 3 1 ionic (unit! D 1 0 100( I 0 1001 119 Porosity <%) 20| Grain Sfcze(mm) ? contact FACIES 1a : Laminated black calcareous mudstone. Lo-angle planar laminae, rare vfg qtz ss laminae abrupt contact FACIES 1a : Massive - weakly laminated calcareous black mudstone abrupt contact FACIES 1c : Laminated siltstone/vfg qtz ss. Calcareous, hz planar laminae, abundant micro pyrite • -- • • _ . . . . 1 - - - •-1 GR (units) J • 1 ionic (units 0 10« ) . 120 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric D-26-D/94-A-14 Fireweed 1 DOIG From: 1655.1 To: 1673.4 #4369 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) GR (units) FACIES 2c : laminated fg-mg qtz ss, lo-angle laminae, abundant concretions, coquina lenses /intraclasts, mg-cg mudstone intraclasts towards upper contact. Syn-sed deflectoin of laminae gives convolute appaerance, good porosity in bitumen stained ss Jfionic (unit: GR (units] ) 1*0 fconic (units) -tow 100( 1*0 100C 100C 121 Porosity (%) Grain Size (mm) . c • c . FACIES 2c : laminated fg qtz ss, lo-angle unidirectional laminae, abundant concretions, coq intraclasts, bitument staining. Good intergranular porosity in bitumen stained ss FACIES 2a : massive-convolute laminated vfg ss/mudstone, abundant soft sed defm abrupt contact, pyrttized, fossil debris FACIES 1a/1c : weakly laminated - massive siltstone-mudstone & vfg qtz ss, planar, horizontal laminae, calcareous, rare echinoid debris. Abundance of vfg ss decreases towards upper contact giving fining upward appearance • - - - -. . - . . . . . . . . . . • - -1 1 r i GR (units) » - V ionic (unit! 0 1' 0 10(K ) 0 100( 122 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 15-21-87-20-W6 #9851 Fireweed (Buick Creek) 1 ,2 ,3 DOIG From: 1558 Cut: To: 1591 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology € i " i o i o ==; M ig O Geological Descriptions TG, C1-C5 GR (units) Sonic (units) FACIES 1a : massive black calcareous mudstone, no traces or body fossils abrupt contact no deformation or rip-ups FACIES 2a/2b coarsening up package of vfg ss & mudstone to mg ss + mg fossil debris abrupt contact FACIES 2e : as below abrupt contact FACIES 2e : as below with basal mudstone-rich interval abrupt contact FACIES 2e : coarsening up package of lo-angle planar bedded fg-mg qtz ss & coquina MISSING CORE Sonic (unit: •1 Bonic (units) 1*0 GR (units] •1*0 1*0 100C 100( 100( 100( 123 FACIES 2a : lo-angle planar laminated vfg qtz ss. Abundant mudstone stringers, concretions, absence of traces and body fossils - PROGRADING SHORFACE ? FACIES 2c/1c : convolutely interbedded/lensed vfg-mg qtz ss with dark grey massive siltstone. evidence of soft sed defm, absence of traces and body fossils, abundant concretions. abrupt contact, erosional,fractured, abundant rip-ups -TSE? upper section of Facies 2f is highly brecciated and fractured coquina, geopetal infill is poorly sorted fg-mg qtz ss FACIES 2f : oversteepened planar bedded coquina with fg qtz ss matrix, abundant fg-mg qtz ss stringers. Evidence of deformations, slumping. Coq is 70% imbricate, transported bivalve fragments -INLET FILL FACIES 2c : oversteepened, convolutely bedded fg qtz ss. Evidence of slumping, abundant bioclastic debris - INLET FILL GR (units) - 1*0 fconic (units) 1*0 100C 100C 124 0 PdVoslry (%) 3 Porosity (%) 20 Grain Size (mm) 1[ FACIES 2f : oversteepened planar bedded to massive to x-bedded coquin, matrix is fg qtz ss, bioclasts are poorly sorted and imbricate, abundant fractures and mudstone intraclasts - INLET FILL FACIES 2c : highly fractured planar bedded fg ss, fossil debris abrupt contact FACIES 1a : massive black mudstone abrupt contact, erosional, angular rip-ups FACIES 2e : x-bedded fg qtz ss & coq, lo-angle bedding, primary structures over-printed by concretions and 'breccia' texture FACIES 2c : bedded fg ss, bedding is planar and lo-angle, scattered bioclasts, abundant fractured concretions abrupt contact FACIES 2c : planar bedded fg ss, mod-angle bedding, mudstone laminae gradatlonal contact FACIES 2e : x-bedded fg qtz ss & coq, abundant concretions & 'breccia' texture abrupt contact, erosional, slumped, rip-ups FACIES 1a : massive silty mudstone -• - • • 1 1 1 1 GR (units) 0 - - - 11 Sonic (unit! 0 1i 0 100C ) 0 100( - - - - - - r - --1 — ,1 1 1 GR (units) » - • - 1 ionic (units a 1 0 100( ) 0 100( 125 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric d-42-H/94-A-13 #7716 Fireweed 1 DOIG From: 1522.2 Cut: To: 1528.9 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology |g|j Geological Descriptions TG, C1-C5 GR (units) Sonic (units) 1 1 - - - - • -SR (units) 0 1i Sonic (unit! 0 1i 0 100C ) 0 100C - - - - - - -- - •• • • — . FACIES 2c : weakly laminated-thinly bedded vfg-fg qtz ss, x - planar bedded, patchy brown bitumen staining & light grey calcite gives mottled appearance, rare micropyrite, rare vertical traces (escape) abrupt contact FACIES 2e : as below abrupt contact FACIES 2c : as below, weakly bedded abrupt contact FACIES 2e : weakly laminated-thinly bedded fg-mg qtz ss + coq abrupt contact FACIES 2c : weakly laminated-thinly bedded fg-vfg qtz ss, horizontal laminae, mottled diagenetic texture, bioturbated? - CHANNEL FILL 126 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 08-18-80-17W6 Scott #7469 1,2 DOIG From: 2034 Cut: To: 2055.6 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) FACIES 2b/2c : massive to x-bedded fg qtz ss, poorly sorted, rare traces, mudstone intervals, vertical fractures, dolomitic FACIES 2c : planar laminated sandstone, dolomitic • HCS vfg silty FACIES 2b/2c : massive to x-bedded vfg-fg GR (units) 1 1 1 1 I ti ionic (unit! D 11 o "out I 0 100( : -_ - -i .1 1 i GR (units) 3 1 ionic (unit! 9 1 0 100( ) 0 1001 127 J !3 Porosity (%) 20| Grain Size (mm) 1 — T ~ —T-ciacite cement, rare styiontes FACIES 2a : convolute to planar laminated vfg qtz ss and silty mudstone, abundant traces, rare fractures, calcite cemented FACIES 1a/2a : 5 coarsening up cycles of lamiated silty mudstone and vfg qtz ss, abundant traces, fracturing, calcite cemented FACIES 2a : highly deformed vfg qtz ss and silty mudstone, slumped, bioturbated, calcite cemented FACIES 1a/1c : as below, abundant bioturbation FACIES 2a : convolutely to planar laminated vfg qtz ss and silty mudstone, flame structures, load casts, calcite cemented, sparse Hz traces FACIES 1a/1c : convolutely to planar laminated silty mudstone and vfg qtz ss, calcareous, soft sed. deformation, abundant sub-vertical fractures, sparse horiz. traces • - -- ' - - - •• •-. - -. 1- • - .1 1 -f GR (units) J 1 ionic (units 3 1 o -toot I 0 100t . . . - - • -128 • in in In 1 -1 1 o CM co in - - - - -o CM 129 C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: 10-13-79-21-W6 Groundbirch 1 ,2 ,3 DOIG From: 2598 To: 2608.2 #7175 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 TG, C1-C5 Porosity (%) — GR (units) Grain Size (mm) _ _ _ ' • j j Sonic (units) Lithology j Geological • \t I j I i Descriptions Iff™ £ i f |8 MM il SI a IrS 'OT QC O Porosity 4%^  Grain Size (mm) -Win 1 CM 1 Porosity (•/.) Grain Size-(mm)-FACIES 2c : laminated vfg qtz ss, planar lo-angle x-laminae, periodic mudstone intervals, Hz fractures, rare Vt traces missing core FACIES 2c : laminated vfg-fg qtz ss, lo-angle planar x-laminae, abundant mudstone filled micro-fractures, stylolites, rare traces FACIES 2c weakly laminated vfg qtz ss, f 1#0 onic (units) 1*0 IGR (units) - •» Ii 10 . _ponic (unit! ,1b 100( 100( 100( 100( 130 stringers FACIES 2c : flaser laminated vfg qtz ss, abundant mudstone stringers, stylolites, occaisional traces, highly distorted structure FACIES 2a : convolute laminated vfg qtz ss & mudstone abrupt, mudstone break FACIES 2c : laminated vfg-fg qtz ss,planar lo-angle laminae, clean, poorly sorted, abundant mudstone filled Hz microfractures, abundant stylolites, mudstone stringers, non-calcite cements, no traces/body fossils Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. 06-07-79-20-W6 Groundbirch 1 DOIG From: 2429.5 To: 2439.6 Scale 1:50 Metric #6856 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) GR (units) Porosity (%) Grain Size (mm) -Porosity (%) Grain Size (mm) -FACIES 2c : laminated vfg qtz ss, planar -convolute Hz laminae, abundant open Hz fractures, stylolites FACIES 2b : mottled fg qtz ss, irregular fractures, visible qtz cement, ? abundant bioturbation? FACIES 2a : interbedded vfg qtz ss & laminated non-calcareous mudstone, abundant open fractures, abundant micropyrite in mudstone, rare Hz traces & : massive fg qtz ss, abundant fractures FACIES 2c : weakly laminated fg qtz ss, planar Hz laminae, occaisional mg ss interbeds, abundant visible dolomite & qtz cements, bioturbated toward lower contact abrupt, mudstone lag & unidentified Hz traces FACIES 2c : as below, very faint laminae, bioturbated at lower contact abrupt, marked by 1st appearanc of Vt traces FACIES 2c : laminated vfg-fg qtz ss, planar jionic (unit: 1 0 . ionic (unit: 10 1 * 0 GR (units) 1 * 100C 100C 10W 100( 132 structures & open fractures, zones of unusual salt& pepper texture, rare zones of abundant mudstone intraclasts, visible dolomite spar & qtz overgrowths, fractures appear to post-date compaction Porosity (%) Grain Size (mm) -GR (units) (Sonic (units. 1*0 100C 100C 133 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 12-01-78-14-W6 Kilkerran #5684 2 DOIG From: 2059.5 Cut: To: 2073.1 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) GR (units) 11 fconic (units Porosity (•/.) Grain Size (mm) -pLrosJty (%) Grain See (mm) -s rr:_: : T •T: •: •: • FACIES 2c : TCS fg-mg qtz ss. poorly sorted, bioturbated at intervals, coarsening-up package boredJburrowed firmground - glosstfungltes Facies 2b : massive qtz ss as below FACIES 2a : massive sanstone and mudstone, hz traces FACIES 2b : massive to HCS, poorly sorted fg qtz ss, moderate traces, bitumen stained intervals, trace pyrite FACIES 2c : poorly sorted qtz ss inter-bedded with mg qtz ss, lo-angle x-bedding, vetical traces increase toward upper contact, massive interval GR (units) 3 - 1 tonic (unit: 1B *0 I) 100< 100( 100< 100( 134 FACIES 2c : as below, visible skolithos, qtz ss is very clean arenite FACIES 2c : as below, traces absent, horizontal fractures FACIES 2c : as below, scattered pyrite gives salt and pepper appearance, abundant fractures, few traces FACIES 2c : x-bedded vfg -vf qtz ss, some coarser interbeds, planar bedding, abundant stylolites, vertical traces, abundant dolomite cement 1 1 1 1 GR (units) 3 11 ionic (unit! 3 11 0 10M ) 0 100C • - •• - • • ::: : ::: 135 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric D21L/94-G-9 Tommy Lakes #10019 DOIG From: 1148.5 Cut: To: 1161.55Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) i t IS io io Vt ice 6! GR (units) 11 Jionic (units]! Porosity (*/•) Grain Size (mm) -4-I Porosity (%) (Grain Size (mm) F I Facies 2e: interbedded ss and coquina, shale partings, abundant stylolites, escape traces Facies 2b: massive fg qtz ss, rare thin coquina interbeds Facies 2g: coquina as below, abundant stylolites Facies 2c: weakly laminated fg qtz ss, rare coquina interbeds, sharp contacts Facies 2g : bivalve coquina, highly abraded, thin sanstone/siltstone interbeds Facies 2b: massive fg qtz ss, rare mudstone laminae, scattered fossil debris GR (units) D 11 Jionic (units!) *0 100( 100( 100< 100( 136 Facies 2g: bivlave coquina with thin sandy interbeds, ubundant stylolites Facies 2b: massive fg qtz ss, convolute shale partings, scatterd fossil debris Facies 2e: interbedded vfg qtz ss and coquina, abundant traces, rare mudstone rip-ups Facies 2b: massive fg qts ss, convolute shale partings, bioclastic debris increasing toward upper contact appearing as lenses and intraclasts Aprupt contact, slumped high-angle Facies 1c: steeply dipping laminated siltstone & vfg ss. Abundant soft sed. and pyrite . . . . . . . . 1 1 r i GR (units) o v ionic (unit! 0 V 0 100C ) 0 100C . . . -137 C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: d-73-F/94-G-9 #5132 Location: Tommy Lakes Contractor: Core #: 1 Formation: DOIG Core Interval: From: 1197 Cut: To: 1215.3 Recovered: Bit type: Size: Coring Time: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology TG, C1-C5 GR (units) Sonic (units) Ufi§! ? § « « IQ: O I Geological Descriptions t (units) Porosity (%»= lo Grain Size (mm) • i i jo"! Porosity (%) Grain Size (mm) -I I F TJ o.o. b -p 0 - o. FACIES 2c : Hz to x-stratified mg sub-lithic arenite, basal lag, pyritized lower contact FACIES 1c : siltsone interbedde with vfg ss and mudstone, soft sed deformation, increasing clacite cement towards upper contact FACIES 1a : black laminated mudstone, abundant pyrite FACIES 1c : laminated siltstone and mudstone, occaisional ripples, scattered bioclastic debris, large anhydrite filled vugs {Sonic (units. GR (units' Jionic (unit: 100( 100C 1*0 Its!) 1*0 100( 100( 138 FACIES 1c : massive siltstone with sandy lenses and occaisional fossil debris, large anhydrite filled vugs FACIES 2b : convolutely laminated fg sub-lithic arenite and siltstone, soft sed. defm., calcareous FACIES 1c : Hz laminated siltstone, rare vert traces FACIES 2c : convolutely laminated vfg lithic arenite and siltstone, scattered fossil debris FACIES 2b: fining upward package of vfg • fg sub-lithic arenite, becoming more calcareous towards upper contact, bioclastic debris, convolute mudstone laminae FACIES 2b : massive vfg sub-lithic arenite, convolute mudstone laminae, abraded bioclastic debris, weakly calcareous, rare calcite filled fractures FACIES 2d : Bioclastic ss, abundant mudstone and lithic interclasts, ss % increases toward upper contact FACIES 2c : stratified vfg sub-lithic arenite, pyrite, bioturbated FACIES 1a : black laminated mudstone, siltsrone and vfg qtz ss, abundant pyrite, rare x-stratification, Hz traces, ss is calcite cemented • — --. -1 1 i" " " 1 GR (units) ) 11 ionic (unit! 3 11 0 100( ) o iooc - - -. . . . . . . 139 C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: d-91-G/94-G-9 #5113 Location: Tommy Lakes Contractor: Core #: 1 Formation: DOIG Core Interval: From: 1257.5 Cut: To: 1269 Recovered: Bit type: Size: Coring Time: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) Halfway ss - vfg qtz ss, planar laminated, dolomitic, increasing fossil debris toward upper contact Facies 1c/1a : lamianted siitsone and mudstone, coarsening upwards to sandstone unit FACIES 1c : laminated siitsone and mudstone,lo angle planar laminae, moderate bioturbation GR (units) Sonic (unit! 1 to GR (units) D 1 Sonic (unit: •0 100( 100( 1*0 100C 100( 140 eg - granule lithic lag FACIES 1a : massive - laminated black mudstone, pyritized and bioturbated upper contact GR (units) 10 100 Sonic (units) 10 100 1000 Porosity (%) Grain Size (mm) 20 V= 1 1000 141 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 16-34-82-16-W6 Two Rivers #5020 2 DOIG From: 1446 Cut: To: 1464.2 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%; Grain Size (mm) ' £ Lithology • Q. •>. •t- ;o> ff JZ . c * Q. o Q a. « a o Geological Descriptions TG, C1-C5 GR (units) Sonic (units) FACIES 2c : HCS vfg-fg qtz ss, patchy calcite cements FACIES 2c : HCS - x-bedded fg qtz ss, moderately sorted, lithic arenite interbeds,patchy calcite cement FACIES 2c : planar x-bedded fg-mg qtz ss, poorly-moderately sorted, patchy calcite cement, rare traces and filled vugs, vague coarsening up texture 3° 1t° Sonic (units 1*0 GR (units) * 11 0 Sonic (unit!) TjO 1*0 iooc 100( 100X 100C 142 FACIES 2c : x-laminated vfg-fg qtz ss, moderately sorted, dolomitic, rare mudstone stringers and interclasts, stylolites, rare escape structures, tidal couplets observed FACIES 2b/2c : massive to lo-angle laminated vfg-fg qtz ss, non-calcareous, abundant mudstone laminae, stylolites, occaisional dolomite filled vugs FACIES 2c : fg quatz aa, lo-angle planar x-lam, moderately sorted, dolomitic • -• - -1 — 1 i i GR (units) ) - 1i ionic (unit! 3 1 0 10(X ) 0 100( . . . . .. .. _ 143 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 16-34-82-16-W6 #5020 Two Rivers Halfway From: 1421.5 To: 1430.8 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology l O ! O = w a: o Geological Descriptions TG, C1-C5 GR (units) Sonic (units) 1 1 r ~ " 1 GR (units) 0 li Sonic (unit! 0 1i 0 100C ) 0 100( — . . . --.. _ . _ :.. FACIES 2c : poorly sorted, fg-mg qtz ss, tabular x-bedded, patchy dolomite cement, visible intergranular porosity FACIES 2b: massive fg-mg qtz ss, convolute mudstone laminae, dolomite cements, rare eg lithic rich interbeds FACIES 2b : dark brown massive muddy qtz ss FACIES2b/2c : massive to weakly laminated fg-mg qtz ss, zones of dolomite cements, vertical fractures 144 Pbroslty (%) Qrajn Size (mm) -] Facies 1a : green claystone interval (paleosol?) FACIES 2b : massive bimodal eg iithic and qtz grains floating in a well sorted fg qtz arenite matrix 1 - - - 1 1 1 GR (units) ) - - - H ionic (unit! D 1i 0 10« ) 0 100( 145 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 2/d-57-l/94-A-11 Buick Creek #3973 DOIG From: 1351.8 Cut: To: 1376.8 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) GR (units) FACIES 2c : laminated fg qtz ss, lo-angle planar laminae defined by mg bioclastic sands, abundant fractures offsetting structure, muddy intervals & rare Hz traces, abundant distorted laminae (faulting?) abrupt, slumped hl-angle contact, abundant mudstone stringers In a vertical position Sonic (unit! U> - t i e - - I M 9 146 >ize (mm) -?3r Grain Size! (mm) -15 r : • T . FACIES 2c : as below, occaisional loading structures, laminae defined by calcite stringers (?bioclastic sands?) FACIES 2c : planar laminated fg-mg qtz ss, lo-angle laminae, occaisional mg ss interbeds (sub-rounded, well sorted), abundant calcite halos assoc with wavy mudstone stringers, rare scattered mudstone intraclasts, traces & bioclasts not observed in ss, rare vert open fractures, rare laminated mudstone rich zones with assoc hz traces Rubble, fg qtz ss FACIES 2c : laminated vf-fg qtz ss, mod-angle laminae, abundant convolute mudstone stringers, loading & defm pX'cTt:S"2a : laminated vfg qtz ss/mudstone, lo-angle laminae, moderate Hz traces, non-calcareous mudstone FACIES 2c/2b : massive to laminated fg qtz 1- 1 r '" i GR (units) 0 1i Sonic (unit! 0 11 0 100( ) 0 100C - • --. _ . 1 1 1 i GR (units) 3 1 ionic (unit! 3 1i 0 100( ) 0 100( — . -147 s I a s i i a v « r v u i V I O I U I C l a n i i u a c u u c L U U I I M W I I I I lithology), lo-mod angle laminae, rare mudstone stringers, several pebble-sized rounded mudstone intraclasts, rare fossil debris, abundant calciete halos, no visible traces FACIES 2c : laminated vf-fg qtz ss, planar mod-angle laminae, abundant wavy mudstone stringers & assoc calcite halos, rare mudstone intraclasts and bioclasts, no visible traces Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric d-68-l/94-A-11 Buick Creek 1 DOIG From: 1392.9 T o : 1417 #3992 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) 1 1 • • 1- - 1 CR (units) D 11 ionic (unit! 0 11 0 100C ) 0 100C . . • - • --Porosity (%}•  Grain Size (mm) TP FACIES 2c : laminated fg qtz ss, mod-high-angle planar laminae, abundant wavy mudstone stringer & assoc traces and calcite halos (?concretions)?, periodic laminated mudstone intervals with overlying mudstone rip-ups, evidence of soft sed defm, slumped high angle contacts, generally sparse fossil debris and bioturbation fractured mudstone stringers & ss intralcasts FACIES 2c : laminated fg qtz ss, mod-high-angle planar laminae, abundant wavy mudstone stringer & assoc traces and calcite halos (?concretions)?, periodic laminated mudstone intervals with overlying mudstone rip-ups, evidence of soft sed defm, slumped high angle contacts, generally sparse fossil debris and bioturbation lens of calcite cemented fg-mg ss, Intraclasts & bioclastic sands 149 Porotity (%) Qrainpize (mm) Ml I I PorosirJ(%) 20 ? 1 I T . : : : T : : : f r : •r: pebble-cobble sized mudstone Intraclasts, deformed contact FACIES 2c : laminated fg qtz ss, mod-high-angle planar laminae, abundant wavy mudstone stringer & assoc traces and calcite halos (?concretions)?, periodic laminated mudstone intervals with overlying mudstone rip-ups, evidence of soft sed defm, slumped high angle contacts, generally sparse fossil debris and bioturbation high angle stringers, faulted, slumped, Irregular contact mudstone-rlch, mudstone rip-ups - contact? mudstone rich, mudstone rip-ups • contact? 1 1 1 1 GR (units) 3 V ionic (unit! D 11 0 100( ) 0 100C • -• - - - • -- - • - - --• - - - • • -1 1 i i GR (units) J 1 ionic (unit: D 1 0 100« ) 0 100( . 150 FACIES 2c : as below, abundant mudstone intraclasts & visible calcite (spar? bioclastic?) FACIES 2c : laminated fg qtz ss, lo-angle planar laminae, abundant calcite halos, rare mudstone stringers, no visible traces FACIES 2a : laminated fg qtz ss, wavy laminae, abundant mudstone stringers, angular mudstone intraclasts, bioturbation assoc. with mudstone C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: d-58-l/94-A-11 Buick Creek #3996 DOIG From: 1367 Cut: To: 1385 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) 1 1 1 4 CR(»nit.,l D 1i ionic (unit! 0 1' 0 100( ) 0 100C " 1- 1 r i GR (units) ) 1 ionic (unit! 0 1 0 100< ) . 0 100( — - -— - -• - . — -FACIES 2c : laminated fg qtz ss, hi-mod angle laminae, abundant mudstone stringers & intraclasts, rare bioclastic horizons with visible moldic porosity, abundant clacite halos/concretions, rare fractures open and filled, sparsely bioturbated, bioclastic sand horizons 152 re porosity <•/.) ain Size (mm) -FACIES 2c : laminated fg qtz ss, hi-mod angle laminae, abundant mudstone stringers & intraclasts, rare bioclastic horizons with visible moldic porosity, abundant clacite halos/concretions, rare fractures open and filled, sparsely bioturbated, bioclastic sand horizons FACIES 2a : 3 fining-up cylces of planar laminated vfg ss/siltstone, hz laminae, abundant micropyrite, moderately bioturbated, calcite halos, ripples, soft sed defm observed at lower contacts -FINING UP CHANNEL FILL7MASS FLOWS - • 1- 1 1 1 GR (units) ) 1i ionic (unit! 0 V 0 100C ) 0 100( 153 C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: d46l/94-A-11 #4172 Location: Buick Creek Contractor: Core #: 1 Formation: DOIG Core Interval: From: 1361.8 Cut: To: 1375.3 Recovered: Bit type: Size: Coring Time: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) GR (units] FACIES 2e : laminated fg-mg qtz ss & coquina, weak lo-angle planar laminae, coquina appears as fractured rinded clasts/lenses showing partial dissolution & geopetal fill, abundant mudstone stringers, absence of traces, fossil debris is highly abraded embricate pelecypod shells, strong deflection of laminae around concretions -compaction abrupt? not visible in core FACIES 2a : Hz laminated vfg ss/mudstone fconic (units 1*0 1b -roea 154 Porosity (%) 5u| Grain Sizer(mnT) 1 IZI. FACIES 2a : laminated, bedded vfg ss/siltstone, weakly planar Hz laminae, abundant mudstone stringers, traces, scattered fine echinoid debris, abundant calcite concretions/halos, soft sed defm strucutres, slumping, rare fractures FACIES 2b : as below FACIES 2f : weakly imbricate, massive -convolute coquina, highly abraded, variable vuggy porosity FACIES 2b : massive fg brown qtz ss abrupt contact, bioclastic rip-ups FACIES 2a : laminated vfg qtz ss & mudstone, planar to convolute laminae, occaisional massive ss intervals, sharp based, cut & fill structures, scattered traces, fossil debris beds (echinoid), rare mudstone intraclasts 1 1 1 1 GR (units) 3 V ionic (unit! D 1i 0 100( ) 0 100C -- • -- -155 CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: d-45-l/94-A-11 #4622 Location: Buick Creek Contractor: Core #: 1 & 2 Formation: DOIG Core Interval: From: 1408 Cut: To : 1427.4 Recovered: Bit type: Size: Coring Time: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology •sis Geological Descriptions TG, C1-C5 GR (units) Sonic (units) Porosity^ Grain Size (mm) 12 Porosity (%) Grain Size (mm) -o ' . O . o«o" °. FACIES 2c : laminated vfg qtz ss, convolute laminae, abundant mudstone at base, abundant sot sed. defm features, rare fractures, cut & fill, bioturbation absent abrupt, ?mudstone lag?, TSE FACIES 1b : convolutely bedded coquina, poorly sorted whole & fragmented pelecpod, brachiopod and eichinoid, delicate & robust, tight calcareous siltstone matrix, abundant mudstone stringers, bedding is inverse graded, abundant deformation structures - MASS FLOW grades from massive - convolute laminated grey siltstone with echinoid debris to coquina abrupt, pyritized FACIES 1a : laminated mudstone, black, calcareous, abundant thin vfg qtz ss stringers and laminae, abundant traces associated with ss 1P ponic (unit GR (units) 1 tonic (units]: 1*0 t (units) 1*0 100( 10(K 100( 100( 156 P o r o s i t y 58] Grain Size (mm) - -contact marked by first appearance of vfg ss laminae FACIES 1a : massive mudstone,black, calcareous, bioturbation absent, scattered echinoid debris GR (units) 3 1 (ionic (unit: 100C 100( 157 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. D-77-I/94-A-11/2 Buick Creek Scale 1:50 Metric #6872 2 DOIG From: 1387.5 To: 1405.5 Cut: Recovered: Printed by STRIP.LOG from WellSight Systems Inc. 1-800-447-1534 C u r v e T rack 1 Poros i ty (%) Gra in S ize (mm) L i t h o l o g y G e o l o g i c a l D e s c r i p t i o n s T G , C 1 - C 5 G R (units) S o n i c (units) Pi Grain Size (mm) Porosity (%) Grain Size (mm) -~m abrupt contact with Facies 1c FACIES 1a : massive mudstone, as below FACIES 2a : laminated vfg qtz ss/mudstone, convolute laminae, abundant trace fossils and mudstone intraclasts FACIES 1a : massive mudstone & floating qtz grains, as below FACIES 2a : laminated-bedded vfg qtz ss/mudstone, wavy laminae, rare trace fossils, deformation at upper contact FACIES 2c : planar laminated vfg qtz ss, lo-angle laminae, rare mudstone stringers & trace fossils, occaisional muddy intervals FACIES 2a : laminated/interbedded vfg qtz ss/mudstone, wavy laminae, abundant traces FACIES 2b/2c : massive - laminated vfg qtz ss, wavy laminae, abundant mudstone intraclasts & trace fossils £onic (unit: to G R (units) D 11 S o n i c (units!) 100C 100C *0 100( 100( 158 Porosity (%) Grain Size (mm) -"561 FACIES 1a : as below FACIES 1a : massive grey mudstone, occaisional interbeds of FACIES 1 (as below, sharp contacts), absence of trace/body fossils, regularly spaced horizontal fractures, abundant well rounded qtz grains (fossils?) floating in massive mudstone, calcareous FACIES 1c : laminated siltstone/vfg qtz ss, minor ripples, abundant micropyrite, no traces observed, ss laminae - STORM EVENT BEDS abrupt contact with FACIES 1a i --. . . . . . . . . 1 1 i i GR (units) J 11 ionic (unit: 9 11 0 100C I . 0 100C . . . . . _ . . . . . . . _ . . . _ . — . : 159 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. D-77-I/94-A-11/2 Buick Creek Scale 1:50 Metric #6872 1 DOIG From: 1373 To: 1385.5 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology TG, C1-C5 GR (units) Sonic (units) Geological Descriptions o ; o = • FACIES 2c : laminated vfg qtz ss, lo-angle planar laminae defined by increasing mudstone content, no body/trace fossils, abundant calcite halos, rare mudstone stringers, excellent reservoir quality in brown ss abrupt, hlgh*angle slumped contact j ton ic (unttSJ i(uniU) 1*0 100C 100C 160 r M U i c o za : lammaiea vwg qiz ss/mudstone, convolute laminae & mudstone stringers, moderate Hz traces, scattered calcite halos FACIES 2c : laminated fg qtz ss, lo-angle laminae FACIES 2b : massive vfg qtz ss, abundant fossil debris (brachiopod, pelecypod) FACIES 2c : laminated - massive fg qtz ss, abundant bioclastic sands, rare mudstone stringers, no traces observed FACIES 2a/2c : 2 coarsening-up cycles of laminated vf-fg qtz ss abrupt mudstone rip-ups FACIES 2c : laminated vf-fg qtz ss, Hz-mod-angle planar laminae, large articulate pelecypod fossil, rare mudstone stringers FACIES 2a : interbedded massive calcareous black mudstone/convolute laminated fg qtz ss, abundant Hz traces 1 1 1 1 GR (units) 0 1i Sonic (unit: 0 1< 0 100C ) 0 100( 161 1 C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: d-86-l/94-A-11 #7200 Location: Buick Creek Contractor: Core #: 3 Formation: DOIG Core Interval: From: 1395 Cut: To: 1413.2 Recovered: Bit type: Size: Coring Time: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) — Grain Size (mm) Lithology i !& < >> *-! * l a a. S X V O • O O 0. eft • Rounding • Oil Shows Geological Descriptions TG, C1-C5 GR (units) Sonic (units) 0 Porosity (14) 30 0 Grain Size (mm) 1 I94 13 FACIES 2g : abraded coquina, lo angle bedding, occaisional qtz ss interbeds, sharp based and graded FACIES 2c : laminated fg qtz ss, weak planar, lo-angle laminae FACIES 2g : coquina in fg qtz ss matrix, lo-angle bedded, weakly graded to massive, sharp based 1 1 1- =1 U K (units) 0 11 ionic (unit! 0 • 11 0 100( ) 0 100( r 196 1395 13 . _'. r 196 1395 13 196 1395 13 \> CO cT cn CO T ~ O l cn -. • -. •. •. • j. .'.;>>.—I . . . . . . CO o • - - - i- - i-. . . . '—•"~ 7 ' • ^  0 I Porerityltt) 20 0 'Grain Size (irtrn) 1 f ! F o 5 Li | i. -;i=p^ - 1 1 r 1 GR (units) 3 1 Sonic (unit 3 1 o ioo< > 0 100( 162 0 I I Porosity (%) 55 0 I I Grain Size (mm) 1 lo-angle laminae, rare mudstone stringers & assoc calcite halos, occaisional sharp-based fining up coquina interbeds with highly abraded, disorganized bioclasts, rare faulting & slump features, soft sed. deformation, flame structures FACIES 2b : massive - weakly planar laminated fg qtz ss, lo angle laminae, moderate mudstone stringers & assoc calcite halos. FACIES 2a : laminated fg qtz ss, wavy planar to convolute lo angle - mod angle laminations, abundant mudstone stringers & bioturbation. --• — _ . .. . 1 1 1 ' !i G R (units) D 1i ionic (unit! 3 1 0 10<K ) 0 100( • - . - - '- •• : - -. . . . - -163 C O R E STRIP LOG WellSight Systems Inc. Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: a-29-K/94-A-10 Buick Creek Scale 1:50 Metric #7438 3 & 4 DOIG/HALFWAY From: 1368 Cut: To: 1386 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 TG, C1-CS Porosity (%) — — • i ! GR (units) ^ — Grain Size (mm) _ _ _ Sonic (units) Lithology j Geological i • ! Descriptions & VI ! H o ills o £ FACIES 2c : bedded mg brown qtz arenite, well rounded/sorted, lo-angle planar bedding, non-calcareous, unusual white diagenetic mottling following structure, strong HC odor, excellent inter-granular porosity abrupt, marked by mudstone break FACIES 2b : mottled fg qtz arenite, mottling caused by patchy light, brown clay FACIES 2c : bedded fg-cg arkosic arenite, planar-Hz bedding, bimodal grainsize distribution, non-calcareous FACIES 2c : TCS-planar laminated fg qtz arenite, non-calcareous, no trace/body fossils Sonic (unit! 1 GR (units) 1 -1J .' ionic (unit! 13 1 100C 100C 100( 1001 164 FACIES 2c : weakly laminated mg qtz arenite, poorly sorted, abundant pebble sized black angular intraclasts, scattered fossil debris FACIES 2c : x-bedded fg qtz arenite, well rounded, moderately sorted, scattered fish debris/qtz pebbles at lower contact (lag), abundant micropyrite towards lower contact, occaisional massive intervals, non-calcareous, no visible trace fossils abrupt, erosional, DOIG/HALFWAY contact FACIES 1a/2c : laminated mudstone/vfg qtz ss, lo-angle planar laminae, non-calcareous, coarsening up, trace fossils appear towards upper contact FACIES 2b : massive mottled (geopetal filled pelecypod molds?) vfg qtz ss, abundant micropyrite & fossil debris FACIES 2a : laminated vfg qtz ss/mudstone, Hz lo-angle planar laminae, non-calcareous, moderate bioturbation, scattered fossil debris, rare TCS, occaisional mudstone intervals FACIES 2b : massive vfg qtz ss, mottled texture, non-calcareous, rare fossil debris, occaisional intervals of planar laminated fg qtz ss FACIES 2c : x-laminated (HCS) vfg qtz ss, interrupted laminae, rare Vt traces, rare brachiopod bioclasts FACIES 2d : bioclastic massive vfg qtz ss, abundant mudstone stringers, whole and fragmented bioclasts abrupt, non-erosional FACIES 2b/2c : massive to laminate vfg qtz ss, Hz planar laminae, calcareous, bioclastic interval (pelecypod) FACIES 2c : x-laminated vfg qtz ss, finely laminated, calcareous - — • - — 1 1 1 1 GR (units) ) 1i ionic (unit! 3 1i 0 100C ) . 0 100C . _ _ . . . . . . . . . _ i i : ; i 165 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: CORE STRIP LOG WellSight Systems Inc. Scale 1:50 Metric 9-43-88-20-W6 7479 Buick Creek 2 DOIG From: 1428.9 To: 1447.1 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 GR (units) Sonic (units) Lithology Geological Descriptions GR (units) rr.-.-r T • k V . - . - . T FACIES 2e : weakly laminated fg-mg qtz ss with imbricate coquina interbeds/lenses, rare fractures, mudstone stringers, coq is poorly sorted, abraded FACIES 2b/2c : weakly x-laminated -massive fg qtz ss, lo-mod angle laminae, rare fractures, mudstone stringers, stylolites FACIES 2a : laminated fg qtz ss & mudstone, convolute laminae, sparset bioturbation abrupt contact? missing core FACIES 2a : laminated mudstone & vfg qtz ss, planar laminae, abundant bioturbation FACIES 2g : bivalve coquina, vuggy & imbricate .{ionic (unit Sonic (units) 1*0 GR (units) 1 0 0 ( 100( 1 * 0 1*0 100< 1 0 0 ( 166 ——j Porosity (%) to H Grain Size (mm) ft ft La 3 3 FACIES 2c : planar - x-laminated vfg qtz ss, rare mudstone intraclasts, moderate bioturbation FACIES 2a : laminated vfg qtz ss, convolute mudstone laminae, abundant bioturbation FACIES 2c : planar-x-laminated vfg-fg qtz ss, weak loangle laminae, massiver intervals, rare bioclasts & mudstone rip-ups FACIES 2a : x-laminated - laminated vfg qtz ss & mudstone, sparse bioturbation FACIES 2b : massive, well sorted vfg qtz ss FACIES 2a : x-laminated vfg qtz ss & mudstone, lo-mod angle laminae, planar towards upper contact, sparse bioturbation assoc with mudstone abrupt contact, mudstone rip-ups FACIES 2c : laminated vfg qtz ss, weak, lo-angle laminae, abundant convolute mudstone stringers - • • • • -• •- • 1 1 1 1 GR (units) 0 11 Sonic (unit! 0 1i 0 100C ) 0 100C - •- - L 167 C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: 09-34-88-20-W6 Buick Creek 1 DOIG From: 1410.7 To: 1428.9 #7479 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Geological Descriptions TG, C1-C5 GR (units) Sonic (units) GR (units) FACIES 2g : massive-bedded semi-imbricate coquina, highly abraded bivalve clasts, rare fg qtz ss interbeds, abundant vuggy/moldic porosity & mudstone intraclasts, both sharp & slumped contacts between graded coquina beds FACIES 2c : laminated fg qtz ss, weak lo-angle laminae FACIES 2g : as below FACIES 2e : inter-bedded coquina & laminated fg qtz ss as below, lo-angle planar laminae, bedding contacts are sharp & gradational, occaisional oversteepened contacts FACIES 2g : massive imbricate coquina as below, abraded, abundant convolute interbeds & lenses of fg qtz ss, moderate abundance of mudstone intraclasts Sonic (unit: 1P 168 0 Porosity (•/.) 20 ,1 0 Grain Size (mm) 1 r - M o i e o 4.3 : lammaiea i g qtz ss, convoiuie laminae, abundant bioclasts, stylolites FACIES 2e : bedded coquina & fg qtz ss, well sorted vuggy coquina interbeds FACIES 2c : laminated vfg-fg qtz ss, lo-angle planar laminae, fractures and deformation noted at lower contact FACIES 2g : massive to weakly oriented coquina, sparse fg qtz ss matrix, abundant vuggy porosity, bioclasts = bivalve, both fining and coasening up cycles observed, rare to abundant mudstone intraclasts FACIES 2c : laminated fg qtz ss as below FACIES 2g : coquina as below, well sorted FACIES 2c : laminated fg qtz ss, lo-angle planar laminae, fractured calcite concretions FACIES 2g : massive coquina as below, abundant vuggy porosity FACIES 2c : weakly planar laminated fg qtz ss, patchy calcite cement FACIES 2g : weakly imbricate-massive coquina, densely packed, vuggy, moderatly sorted, abraded, fg qtz ss matrix and interbeds, rare mudstone intraclasts Sonic (unit 1 GR (units) 100C 100C GR (units) 10 100 Sonic (units) 10 100 1000 1000 169 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. 2/d-96-l/94-A-11 Buick Creek 4 DOIG From: 1389 To: 1416 Scale 1:50 Metric #7520 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions GR, Sonic GR (units) Sonic (units) 1 1 1- 1 CB (unite) 0 1i Sonic (unit! 0 11 0 100C ) 0 100C 1 1 • 1 1 GR (units) 0 - M ionic (unit! 0 1i 0 100t ) . 0 100( . . . --Porosity 4%f-Grain Size (mm) 1 Porosity (%) 55| ImlllSllB (linn) 11 upper sandstone contact not visible In core FACIES 2c : massive-laminated-x-laminated vfg-fg qtz ss, planar low-moderate angle laminae, rare mudstone stringers, scattered calcite halos following structure, water escape structures, no body/trace fossils 170 FACIES 2b : massive fg qtz ss FACIES 2c : massive-laminated-x-laminated vfg-fg qtz ss, planar mod-hi angle laminae, rare mudstone stringers, scattered calcite halos following structure, water escape structures, no body/trace fossils GR (units) * 11 sonic (unit! 11 100C 100( FACIES 2c : massive-laminated-x-laminated vfg-fg qtz ss, planar mod-hi angle laminae, rare mudstone stringers, scattered calcite halos following structure, water escape structures, no body/trace fossils FACIES 2c : weakly laminated vf-fg qtz ss, moderate mudstone stringers, rare calcite halos, scattered bioclastic sands, no trace fossils FACIES 2c/2a : wavy laminated vfg qtz ss, mod-low angle laminae, abundant mudstone stringers grading to cm scale interbeds, no 171 Porosity (%) Grain Size (mm) -1 FACIES 2c : planar laminated - x-laminated vf -fg qtz ss, lo-hi angle laminae, irregular mudstone stringers, abundant mudstone intraclasts, no traces or bioclasts abrupt, soft sod defm, slumped FACIES 1c/2a : convolute laminated siltstone/mudstone grading up to vfg ss/mudstone, abundant mudstone intraclasts, soft sed defm features FACIES 2a : convolute laminated vfg qtz ss/mudstone, abundant mudstone stringers & bioclastic sands MISSING CORE -1- 1 1 1 GR (units) 0 1i Sonic (unit! 0 1i 0 100C ) o iooc . . . • - • - • -- - • 172 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric d-6-A/94-A-14 Buick Creek #7538 2 DOIG From: 1376 Cut: To: 1386 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) Lithology Geological Descriptions TG, C1-C5 GR (units) Sonic (units) Grain Size (mm) Porosity (%) Grain Size (mm) - T B I FACIES 2c : laminated vfg-fg qtz ss, planar-lo-angle laminae defined by white ?bioclastic sands/spar?, laminae are disrupted & offset by numerous sub-vertical faults & water escape structures abrupt, slumped pyrltized FACIES 1a : massive to laminated mudstone, laminae are planar, lo-angle and defined by vfg qtz ss, calcareous, regularly spaced Hz fractures, scattered echinoderm debris £bnic (unit: 1*0 GR (units) |onlc (ui 100C 100< nM) 1*0 100( 100( 173 Weil Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. d-6-A/94-A14 Buick Creek 1 DOIG From: 1358 To: 1376 Scale 1:50 Metric #7538 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 GR (units) Sonic (units) Lithology Geological Descriptions !g|Si iity (%) Grain Size (mm) Porosity (%) I Grain Size (mm) -I J f t FACIES 1c : weakly laminated siltstone, planar Hz laminae, scattered echinoid debris, calcareous abrupt sharp contact FACIES 1a : laminated dark grey mudstone, convolute • planar lo-angle laminae, scattered echinoid debris, trace fossils absent abrupt coarse sand/pebble lag • TSE? FACIES 2c : laminated fg qtz ss, lo-angle planar laminae.occaisional water escape structures & vertical traces disrupting laminae, rare mudstone stringers, occaisional sub-vertical fractures offsetting laminae, abundant calcite halos, rare bioclastic sand laminae sonic (unit! 1 GR (units) 1 fconlc (units!) - 1 b 1» t (uniK) •0 1*0 100C 100C 100( 100< 175 0 3 Ur 0 j Porosity! (W) • 0 I Grain Size (mm) I 1 ; 1 FACIES 2c : laminated vf-fg qtz ss, planar lo-angle laminae, abundant zones of calcite occlusion halos (10-30cm) occaisionally fractured, absence of trace/body fossils, rare mudstone stringers, fluid escape structures, rare mudstone intraclasts FACIES 2c : laminated vf-fg qtz ss, planar lo-angle laminae, abundant zones of calcite occlusion halos (10-30cm) occaisionally fractured, absence of trace/body fossils, rare mudstone stringers, fluid escape structures FACIES 2c : laminated vf-fg qtz ss, planar-lo-angle laminae defined by ?bioclastic sands/spar?, bioclastic sands coarsen towards upper contact, ss is moderately sorted, sub-rounded, occaisional wavy mudstone stringers, absence of trace/body fossils — - --1— • -1 1 1 GR (units) ) - 11 ionic (unit! ) 1i 0 100( ) 0 100C - _ . _ .. _ • - -- -. _ _ 176 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric d-76-l/94-A-11 Buick Creek 4 DOIG From: 1391.6 To: 1409.6 #7623 Cut: Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 GR (units) Sonic (units) Lithology Geological Descriptions re := ™ 0 0 = VI tc .0 Porosity (%) Grain Size (mm) ' Porosity (%) I Grain Size (mm) -abundant concretions and calcite cemented horizons towards upper contact, no bioclasts, calcite source may be calcareous mudstone rip-ups FACIES 2e : laminated fg qtz ss with coq interbeds, high angle planar laminae/interbeds, abundant vuggy porosity & pebble-coarse sand sized interclasts assoc. with abraded coq horizons, abundant fractured coquina, geopetal filled Hz & Vt fractures, rare deformed mudstone intraclast horizons & mg qtz ss horizons, no traces observed 1- 1 1 1 GR (units) 0 V ionic (unit: 0 11 0 100( ) 0 100( 1 1 1 1 GR (units) 0 - • -11 ionic (unit! 0 1< 0 10W ) 0 100< L . . - - - • • L 177 Porosity (%) Grain Size (mm) UN erosional contact (RSE?) FACIES 2a : convolute laminated vfg qtz ss/mudstone, highly deformed, abundant bioturbation, deformed at lower contact abrupt, deformed, slumped contact abundant micropyrite FACIES 1a : massive, medium-grey calcareous mudstone, abundant Hz fractures, abundant rounded qtz grains floating in mudstone matrix (<1%) FACIES 1a : laminated mudstone/vfg qtz ss (>90% mudstone) = "phosphatic shale", abundant micropyrite, calcareous, no visible traces - - -1 1 1 1 GR (units) a 1 ionic (unit! 0 1 0 10<K ) 0 100C — _ -178 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric d-76-l/094-A-11 Buick Creek #7623 3 DOIG From: 1361 Cut: To: 1373 Recovered: Printed by STRIP.LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 ROP (min/m) Gas (units) TG, C1-C5 Lithology t i S " to ce o Geological Descriptions Gas (units) 50 lo.o. d«o- o ; ; T . ; . ; |o'.<>.'b ° o' ° FACIES 1a : calcareous black laminated mudstone, occaisional vfg qtz ss stringers FACIES 1a/2a : laminated vfg qtz ss/mudstone (50%), fine planar Hz to weakly rippled laminae, rare traces, coarsening upward to facies 2b, massive to laminated vfg qtz ss abrupt, coarse pebble lag over 30cm - TSE? 179 ROPlminW 5! Gas (units) - • - -50 ss and mudstone, abundant rip-ups, laminae at lo-mod-angle, vertical escape traces FACIES 1a : massive dark grey calcareous mudstone, floating rounded qtz grains as in core #4 180 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric d-39-E/94-A-14 Buick Creek # 8724 1 DOIG From: 1490 Cut: To: 1508 Recovered: Printed by STRIP .LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 GR (units) Sonic (units) Lithology Geological Descriptions Baretity (%) Grain Size (mm) 1 N FACIES 2c : laminated vfg qtz ss, non-bioturbated, planar laminae •MIDDLE/UPPER SHOREFACE FACIES 2a : x-laminated vfg qtz ss, planar laminae, abundant bioturbated mudstone stringers - LOWER/MIDDLE SHOREFACE FACIES 1c : laminated siltstone & massive bioclastic siltstone interbeds, sharp bioturbated contacts, planar laminae FACIES 1b : massive coq, abundant mudstone stringers, whole & abraded brachiopod, pelecypod, eichinoderm. FACIES 1c : massive black siltstone with convolutely interbedded/iensed bioclastic ss, ss is massive, bioclasts are are poorly Sonic (unit: 1*0 100C 100( 181 tf f> —, Porosity (%) k) I Grain Size (mm) • .T- • —T~ abraded and whole FACIES 21: massive coq, abraded, fining up to fg carbonate sands FACIES 2c : laminated fg qtz ss & fg bioclastic debris FACIES 2b : massive fg qtz ss, bioturbated FACIES 1a : massive mudstone, abundant fossil debris FACIES 2b : massive fg qtz ss abrupt, pyritized FACIES 1a : massive mudstone, occaisonal bioclastic-rich intervals. Bioclasts delicate, random, fragmented to whole bivalve and brachiopod, non bioturbated FACIES 1c : Laminated siltstone with vfg qtz ss interbeds. Interbeds are mm - cm scale, abundant bioturbation, scattered echinoderm debris 1 1 1 1 GR (units) 0 11 Sonic (unit; 0 V 0 100C ) 0 100C • - • • • -. . . . . . . . - .. _ - -Porosity (%) Grain Size (mm) T O ; 1 100 1000 182 Well Name: Location: Contractor: Core #: Formation: Core Interval: Bit type: Size: Coring Time: C O R E STRIP LOG WellSight Systems Inc. Scale 1:50 Metric d-35-A/94-A-14 #7679 Buick Creek 1 DOIG From: 1353 Cut: To: 1375 Recovered: Printed by STRIP.LOG from WellSight Systems Inc. 1-800-447-1534 Curve Track 1 Porosity (%) Grain Size (mm) TG, C1-C5 Sonic (units) Lithology Geological Descriptions F r . - . ; - T - . . . s" •.' • FACIES 1c : convolute laminated siltstone/vfg ss, slumped contacts, soft sed defm structures, rare ripples, no visible traces • MASS WASTING (see upper unit • 4622) FACIES 2c : disrupted, convolute laminated mudstone/siltstone, abundant bioturbation, dewatering structures? FACIES 2c : laminated siltstone/mudstone & vfg ss interbeds, generally Hz planar laminae with rare wavy laminae (ripples?), rare traces, bedding contacts are sharp, non calcareous mudstone Facies 2g : eg pebble lag abrupt, TSE? FACIES 2c : brown, weakly laminted fg qtz ss, laminations difficult to see due to uniform lithology, mod-hi angle planar laminae, scattered mudstone stringers, abundant calcite concretions/halo assoc. with fossil debris, fractures, mudstone stringers 1 1 ionic (unit! 5 11 0 100C • ~ — - - -- • .-183 abrupt, marked by 1st appearance of concretions FACIES 2c : brown, weakly laminated fg qtz ss, Hz • oversteepened laminae, scattered mudstone stringers, patchy zones of calcite cement follow depositional texture, rare fossil debris FACIES : 2c/2a laminated fg qtz ss, oversteepened mudstone laminae, minor fossil debris, mudstone stringers FACIES 2b : massive brown well sorted fg qtz ss, well sorted, scattered mg calcite spar FACIES 2b/2c : laminate-massive fg qtz ss, convolute & distorted hi-angle mudstone laminae (oversteepened), scattered fossil debris, traces assoc with mudstone intervals 1 1 onic (unit! ) 1i 0 100C . . . - --. - - . . -1 - 1 ionic (unit D 1 ) 0 10(K . . . . . 184 FACIES 1c : laminated siltstone, calcareous, oversteepened laminae, scattered fossil debris FACIES 2b : massive vfg qtz ss APPENDIX C Catalogue of Thin Sections Well ID C O R E * SECTION P L U G * INTERVAL (m) FACIES D-21-L/94-G-9 10019 1 1 10p 1160.1-1161.55 2b 1 2 3p 1151.4-1152.8 2f 1 3 2p 1149.9-1151.42 2b d-73-F/94-G-9 5132 1 1 43 1211.5-1212.9 2e 1 2 38 1210-1211.5 2b 1 3 19 1205.7-1207.1 2d 1 4 1 1197-1198.4 2b d-91-G/94-G-9 5113 1 1 57 1257.5-1259 2b d-39-E/94-A-14 8724 1 1 6 1497.5-1499 2c 1 2 5 1497.5-1499 2f 1 3 1 1490-1491.5 2c 09 34 88 20 7479 1 1 72 1427.4- 1427.6 2c 1 2 62 1425.2-1425.4 2g 1 3 59 1424.5-1424.8 2c 1 4 44 1421-1421.2 2c 1 5 14 1413.8-1414 2c 2 1 120 1446.6-1446.7 2b 2 2 112/111 1442.5-1442.8 2b 2 3 103 1438.8-1439.2 2b/2d 2 4 79 1429.9-1430 2e d-86-l/94-A-11 7200 3 1 113 1410-1410.4 2b/2d 3 2 74 1400.4-1400.7 2b 3 3 70 1399.4-1399.7 2f d-45-l/94-A-11 4622 1 1 1412 1a/2f 1 2 1412.1 2f d-35-A/94-A-14 7679 2 1 71 1371.5-1371.7 2b 1 2 31 1363.1-1363.4 2c 1 3 20 1360.6-1360.7 2c 1 4 1356.5 2c d-46-l/94-A-11 4172 1 1 40 2f 1 2 24 2b 1 3 16 2e 1 4 17/16 2c 186 Well ID CORE# SECTION P L U G * INTERVAL (m) FACIES 1 5 16 2e 2/d-57-l/94-A-11 3973 2/3 1 70 2c 2/3 2 56 2c 2/3 3 21 2c 2/3 4 6 2c d-58-l/94-A-11 3996 1 1 16 2b 1 2 36 2b 1 3 52 2a d-68-l/94-A-11 3992 2 1 77 2g 1 2 68/67 2c 1 3 27 Halfway ss 1 4 22 Halfway ss b-77-l/94-A-11/2 6872 2 1 37 2c 1 2 21 2c 1 3 3 2c 1 4 1/2 2c d-76-l/94-A-11 7623 4 1 39 2c 4 2 32 2e 4 3 23 2b 4 4 15 2b d-6-A/94-A-14 7538 2 1 2a 2 2 67 2c 1 1 41 2c 1 2 23 2c 1 3 21/22 2c 1 4 2 2c 2/d-96-l/94-A-11 7520 4 1 55 2e 3 1 45 2b 3 2 24 2b a-29-K/94-A-10 7438 4 1 1383.5 2f 4 2 49 2c 4 3 44 Halfway -massive ss 4 4 17 Halfway - bedded ss 01 07 85 15 10581 1 1 1476.25 2b a-66-l/94-A-10 9621 1 1 12 2c 1 2 11 Halfway ss 187 Well ID CORE# SECTION PLUG# INTERVAL (m) FACIES 1 3 5 Halfway ss C-80-L/94-A-11 4530 4 1 5th from top 2b 4 2 2f 12 35 87 22 10155 1 1 38 2c 1 2 10p 2c 1 3 8p 2f 1 4 12 2f 04 03 88 22 10012 1 1 24 2b 1 2 22 2e 1 3 ast7 2e 1 4 3 2c b-64-l/94-A-12/2 4914 1 1 1713.5 1c 1 2 1701.25 1a 1 3 9 2c 15 21 87 20 9851 1 1 >25 2f 1 2 8 2f 1 3 1 2d b-26-D/94-A-14 4369 1 1 48 2b 1 2 46 2e 1 3 38 2c 1 4 1 2b D-6-D/94-A-14 4454 1 1 13 2e 1 2 6 2c 2/06 04 86 20 6693 1 1 9 2b 10 13 79 21 7175 1,2,3 1 ast8 2c 1,2,3 2 top of core3 2c 06 07 79 20 6856 1 1 7 2c 1 2 2431.75 2a/2b 04 29 83 18 9970 1 1 3p 2f 16 34 82 16 5020 2 1 24 2c 2 2 6 2c 1 1 28 Halfway ss 1 2 12 Halfway ss 12 01 78 14 5684 1 1 26 2b 188 Well ID CORE# SECTION PLUG# INTERVAL (m) FACIES 08 18 80 17 7469 1 1 4 2b 01 05 88 21 9890 2 1 14 2e 01 05 88 21 9890 1 1 1651.25 2g 1 2 2 2c C-11-I/94-A-13 C11I/94A13 1 1 1500 2c 11 29 87 21 9971 1 1 12 2g 1 2 10 2c 14 31 87 21 9972 1 1 24 2f 1 2 below plug 9 2b 1 3 1 2f 10 36 87 22 10582 1 1 1 2c d-42-H/94-A-13 7716 1 1 32 2c 189 APPENDIX D Core Analysis Data FACIES | Porosity (%) | Kmax (mD) | Kv (mD) FACIES Porosity (%) | Kmax (mD) Kv (mD) 2/d-57-l/94-A-11 2/d-96-l/94-A-11 11 9.5 4 0.76 11 13 25.9 9.63 11 8.8 6.6 0.86 11 13 25.9 9.63 11 10.5 7 0.84 11 6.9 4.36 0.19 11 7.5 3.4 0.09 11 13 25.9 9.63 11 9.7 8.8 0.16 11 14.5 28.4 18.3 11 11.8 20 3.2 11 15.5 38.9 25.1 11 7.4 4.6 0.12 11 15.5 38.9 25.1 11 6.3 1.4 0.39 11 15.3 49.2 38.3 11 6.8 1.1 0.3 11 15.3 49.2 38.3 11 6.4 0.87 0.34 11 13.1 11.2 2.94 11 9.4 6.8 0.75 11 13.1 11.2 2.94 11 4.9 1.5 0.05 11 14 22 1.9 11 8.8 3.5 0.64 11 12.3 9.06 3.89 11 10.1 8.6 0.67 11 12.3 9.05 3.89 11 12.1 21 2.4 11 4.5 0.11 0.04 11 8.5 3.3 1.5 11 4.5 0.11 0.04 11 9.5 10 2.2 11 15.3 38.2 36 11 8 2.9 1.2 11 13.1 16.5 12.1 11 8.5 4.3 0.6 11 13.1 16.5 12.1 11 8.3 3.5 0.97 11 5.6 1.46 0.1 11 1.9 0.07 0.01 11 11.2 11.3 0.21 11 0.8 0.03 0.01 11 14.2 28.3 19.6 11 3.9 0.14 0.05 11 14.2 28.3 19.6 11 2.1 0.07 0.05 7 14.4 24.7 16 11 3.1 0.19 0.06 7 12.8 22.9 5.86 11 8.9 17 0.18 7 12.8 22.9 5.87 11 10.3 24 0.23 11 10.6 5.59 3.86 11 8.2 14 0.07 11 10.6 5.59 3.86 11 9.4 15 1.1 11 11.2 4.35 0.21 11 2.3 0.04 0.01 11 7.9 0.97 0.09 11 11 11.9 6.72 3.85 11 8.2 2.8 0.6 11 11.5 5.17 2.42 11 13.5 51 21 11 9.9 2.37 1.53 11 4.3 4.3 2.8 11 9.8 3.91 0.43 11 14.9 54 14 11 9.8 3.91 0.43 11 15.1 66 52 11 12.9 10.8 3.44 11 14.4 50 8.3 11 12.9 10.8 3.44 11 15.5 76 65 11 10.9 9.07 0.3 11 14.8 64 7.5 11 9.2 4.87 0.26 11 0.8 0.03 0.01 11 9.4 4.3 0.64 190 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 11 13.7 49 3.3 11 9.2 6.41 0.11 11 14.8 60 36 11 12.4 16.9 11.6 11 7 14 1.6 11 12.4 16.9 11.6 11 12.9 56 16 11 9.3 5.6 0.43 11 13.2 0.02 0.01 11 12.6 19.8 4.28 11 13.5 35 11 11 5.2 1.72 0.24 11 15 65 13 11 12 14.7 9.51 11 1.7 0.03 0.01 11 10.3 2.9 0.71 11 6.4 1.9 1.3 11 13 26.9 3.92 11 9.2 7.9 2.4 11 8.7 7.29 11 9.1 5.9 0.25 11 12.9 15.5 9.96 11 12.5 54 1 11 7 2.04 0.3 11 13.5 63 9.2 11 8.3 1.25 0.26 11 18.7 177 108 0 2.1 11 15.4 89 57 0 5.4 0.18 0.16 11 8.9 4.8 2.9 0 4.5 0.32 0.13 11 16.1 74 40 11 15.6 28 22.3 11 14.4 68 53 11 15.6 28 22.3 11 15.4 80 40 11 12.2 15.8 13.2 11 2.2 0.06 0.01 11 12.2 15.8 13.2 11 15.5 74 16 11 8.9 5.15 0.45 11 14.4 59 10 11 9.4 7.65 0.49 11 2 0.01 0.01 11 12.6 15.9 7.67 11 16.5 106 47 11 12.6 15.9 7.67 11 11.1 44 25 1 3.2 0.05 0.03 11 14.8 65 34 0 3.4 0.11 0.09 11 7.5 8.4 3.2 d-58-l/94-A-11 11 13.2 39 16 11 11.4 12 5.3 11 8.3 12159 172.25 11 5.7 5.4 0.36 11 2.5 0.39 0.01 11 9 27 0.1 11 5.5 8.4 0.01 11 2.4 0.14 0.05 11 6.3 9.3 0.08 0 7.6 1.7 0.36 11 12.1 13 4.1 0 12.9 24 21 11 8.1 11 0.13 11 13.7 41 27 11 12.8 23 6.6 11 11.5 9.2 3.8 11 10.1 5.9 2.3 11 2 0.05 0.01 11 14.1 52 26 11 4 0.06 0.01 11 15.1 58 44 11 3.2 2.7 1.9 11 4.6 1.7 0.05 11 15.8 97 50 11 13.1 30 16 11 17.2 123 72 11 7.9 16 5.9 11 2.4 0.04 0.01 11 7.6 19 0.69 11 15.6 69 27 11 13.8 45 22 11 15.3 66 45 11 5.3 4.3 0.03 11 6.8 5.5 0.55 11 14.5 58 42 11 2 0.09 0.04 11 15.5 74 57 11 5.6 1 0.37 11 3.1 1.2 0.02 191 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 11 9.4 5.6 0.87 11 14.4' 66 37 11 2.6 0.05 0.04 11 12.2 34 0.14 11 8.7 1.1 0.69 11 14 38 20 11 8.3 2.6 1 11 7.8 15 0.39 09 34 88 20 W6 11 2.6 0.38 0.07 11 13.3 41 16 6 13.8 1.81 0.23 11 3 0.3 0.01 6 11.7 57.7 15.2 11 7.2 3.1 0.42 6 0.07 0.09 0.04 11 12 20 9.1 6 15.4 45 0.14 11 13.5 39 14 6 17.8 1.52 0.28 11 12.3 38 19 6 0.07 0.09 0.04 11 2.9 5.1 0.01 6 10.5 0.78 0.09 11 5.4 7.8 0.08 6 10.3 0.63 0.1 11 10 14 0.1 6 12.3 0.91 0.16 11 10.6 7.1 1.2 6 13.6 4.71 1.24 11 3 0.67 0.01 6 13.6 4.71 1.24 11 17 134 130 6 12.8 1.8 0.55 11 7.3 8.4 0.81 6 8.5 0.4 0.06 11 13.9 54 14 6 6.3 0.59 0.06 11 15.6 90 48 6 13.7 44.6 10 11 2 0.3 0.02 6 13.3 1895 43.6 11 13.6 75 36 11 5.1 0.25 0.12 11 9.3 25 24 6 11.9 4.51 0.13 11 15 60 28 6 11.2 1.17 0.28 11 11.8 19 5.6 10 6.7 0.33 0.25 11 6.7 7.8 0.05 10 8.8 0.4 0.05 11 14 48 28 10 5.5 0.06 0.03 11 15.2 76 57 10 12.8 0.19 0.04 11 14.5 71 35 10 6 0.2 0.06 11 13.5 56 11 10 7.1 0.38 0.11 11 2.7 0.03 0.01 6 11.5 0.77 0.36 11 13.7 39 24 6 11.4 5.23 0.4 11 5.4 0.29 0.13 6 11.4 5.23 0.4 11 4.7 0.25 0.02 6 7.5 0.22 0.04 11 7.3 1.3 0.62 6 4.6 0.16 0.14 11 10.5 13 10 6 7.2 1.52 0.19 11 8.7 1.1 0.71 6 5.5 0.2 0.08 11 1 0.02 0.01 6 7.9 0.35 0.22 11 6.6 0.71 0.18 0 6.4 3.04 0.49 11 1.6 0.02 0.01 10 1.6 0.01 0.01 11 13.5 43 26 10 10.3 0.14 0.09 11 14.3 68 65 10 7.8 0.15 0.03 11 7.2 1.9 1 10 8.9 0.23 0.04 11 7.2 0.52 0.39 10 11.1 4.24 0.47 11 9.8 11 5.6 11 4.4 0.1 0.05 11 9.7 9.1 4.8 6 14 1.91 0.47 11 3.1 0.21 0.01 192 FACIES Porosity (%) | Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 6 14 1.91 0.47 11 1.9 0.03 0.01 6 9.1 0.33 0.05 11 2.1 0.04 0.01 6 10 1.54 0.2 11 1.4 0.01 0.01 6 12.5 1.98 1.52 11 1.5 0.01 0.01 6 12 9.9 0.29 11 1.5 0.01 0.01 6 10.4 1.46 0.1 11 1.5 0.01 0.01 6 11.5 2.45 0.55 11 1.2 0.01 0.01 6 11.4 4.18 1.34 11 0.8 0.01 0.01 6 9.6 0.6 0.21 11 1.3 0.01 0.01 6 12 2.09 1.33 6 8.9 0.47 0.14 b-77-l/94-A-11/2 6 8.7 0.92 0.37 6 5.7 0.21 0.07 11 11.8 6 8.8 1.01 0.54 11 8.2 6.6 0.06 6 4.1 0.07 0.04 11 16.6 87 27 6 4.9 0.08 0.03 11 15 35 13 6 4.3 0.05 0.01 11 14.9 33 12 6 7.7 0.15 0.1 11 13.6 35 1.4 6 6.1 1.93 0.07 11 7.5 2.6 0.05 6 4.6 0.07 0.03 11 7.6 0.94 0.03 6 10.6 0.4 0.05 11 15.9 55 38 11 5.8 2.32 0.07 11 11.6 24 0.13 11 8.2 28.3 0.16 11 13.1 19 6.1 11 9.9 17 0.69 11 13.2 22 4.9 6 7.3 6.8 0.13 11 15.4 38 18 6 11.3 6.5 0.07 11 14.5 33 17 6 9.1 0.36 0.22 11 4.6 0.05 6 8.3 11.8 3.77 11 14.8 40 15 11 8.3 0.29 0.04 11 14 30 9.9 11 9.1 11.8 3.77 11 2.1 0.03 11 11.9 0.74 0.08 11 14.5 31 17 11 6 1.86 0.1 11 14.3 29 14 6 7.3 0.2 0.06 11 14 33 23 6 11.1 3.55 0.19 4 0.72 6 7.9 0.06 0.03 11 9.7 4.8 3.6 6 7.9 0.06 0.03 4.9 0.04 11 6.6 3.11 0.05 11 8.8 4.1 0.05 11 11.4 9.31 1.83 11 8 3.2 0.29 6 10.5 27.4 0.23 11 4.4 0.47 6 8 0.15 0.07 11 3.4 0.12 6 11.4 9.31 1.83 11 7.1 0.25 6 7.9 0.06 0.03 11 6.2 3.7 2.4 6 11.4 9.31 1.83 11 10.5 4.7 3.2 10 11.4 16.8 0.15 11 9.5 3.1 1.9 10 8.1 15.7 0.12 11 4.1 0.23 0.02 10 10.4 7.64 0.35 0 3.4 0.06 10 13.5 46.4 16.5 0 2.1 0.01 193 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 10 9.2 11 0.13 11 7.5 1.8 0.14 10 13.5 46.4 16.5 11 11 5.8 3.4 10 7.6 3.82 0.15 11 2.9 0.02 10 7.6 3.82 0.15 11 9.2 1.7 0.95 10 5.2 0.06 0.01 11 6.5 0.36 0.1 10 10.6 9.13 0.1 0 2.2 0.06 11/7 8.8 5.59 0.31 d-35-A/94-A-14 11/7 13.4 14.8 6.96 11/7 5.9 0.75 0.07 11 5.8 6.4 0.03 11/7 4.1 0.86 0.06 11 11.8 9.84 11/7 6.2 2.11 0.15 11 12.4 10.9 1.95 11/7 5.5 0.31 0.1 11 12.2 11.4 0 1.8 0.02 0.01 11 5.2 0.04 0.03 0 2.2 0.01 0.01 11 10.6 3.97 6 5.6 28.4 0.1 11 8.9 1.37 0.1 0 2.9 0.02 0.01 11 12.6 17 10.4 0 7.3 0.54 0.24 11 7.9 3.1 0 4.6 0.05 0.02 11 4.5 1.44 0.03 0 13.8 27.4 11.7 11 13.1 15.6 8.28 11 13.8 27.4 11.7 11 11.7 8.69 1 11 2.5 0.03 0.01 11 9.6 1.91 11 11.5 24.1 4.97 11 4.9 2.23 11 11.2 29.4 0.1 11 3.3 0.02 11 2.6 0.05 0.01 ' 11 14.1 37.3 11 16.4 43.1 21.1 11 13.7 17.4 9.88 11 9.5 9.66 0.4 11 12.5 13.6 11 14.3 27 4.67 11 8.1 3.76 1.95 11 14.3 27 4.67 11 9.2 1.52 0.62 11 3 0.02 0.01 11 11.6 5.1 11 5.7 3.86 0.01 11 12.2 5.91 3.01 11 11.6 7.35 2.12 11 4.5 0.04 0 2.2 0.07 0.01 11 12.7 15.1 0 2.3 0.02 0.01 11 13.7 17.6 11.2 0 2 0.06 0.01 11 12.8 7.37 2.95 7 16.5 57.2 42.9 11 12 4.41 3.96 7 2 0.02 0.01 11 11.6 5.54 7 16.1 71.3 35.2 11 12.1 6.6 5.9 0 3.3 0.09 0.05 11 10.9 3.77 0 16.1 71.3 35.2 11 13.5 12 10.1 0 3.3 0.09 0.05 11 13.4 11.6 10.2 0 4.5 0.06 0.01 11 7 0.18 0 4.3 0.11 0.01 11 6.8 0.26 0.05 0 2.8 0.06 0.01 11 13 17.5 0 4.5 0.08 0.02 11 10.7 4.26 0.88 0 6.2 0.41 0.06 11 11.8 6.9 3.05 11 11.4 11.8 5.04 11 11.6 8.45 11 12.8 13.2 5.99 11 11 5.06 2.82 194 FACIES | Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 11 10.6 6.42 2.03 11 11.8 5.76 4.56 a-29-K/94-A-10 11 11.6 6.84 11 12.6 9.99 6.37 1 11.3 0.14 11 12.7 10.3 8.46 0 5.9 0.08 11 10.5 3.44 0.37 0 6.8 11 10.1 1.89 7 7.2 11 12.1 7.55 5.24 7 6.9 11 12.1 10.1 5.06 d-39-E/94-A-14 11 7.5 2.48 11 13.5 21.4 0 4 0.07 11 8.7 0.88 0.23 9 1.3 0.04 11 10.3 2.71 1 1.3 0.02 11 9 1.39 0.33 6 11.3 0.45 11 6.7 0.15 6 11.9 0.4 11 8.4 0.7 0.27 6 1.7 0.06 11 11.1 5.86 1.89 d-46-l/94-A-11 11 10 3.35 11 7.4 0.32 0.09 10 8.5 1114.58 192.52 11 8.6 2.26 10 6.8 3.6 0.44 11 7.7 1.39 10 12 19 5.3 11 7.7 2.73 0.1 10 4.1 2.8 0.01 11 7.8 0.57 0.2 10 5.3 0.13 0.05 11 9.9 4.32 10 8 9.4 0.3 11 9.1 2.66 0.24 10 13.1 20 5.8 11 6 0.16 10 6 0.32 0.05 11 6.4 0.19 0.14 10 8.7 0.3 0.01 11 10 4 0.05 0.05 11 6.3 0.22 10 6 2.1 0.01 11 6.2 0.12 0.06 10 8.4 7.5 1.3 0 9.1 2 10 8 22 0.42 7 12.1 11.4 4.5 10 9.8 31 22 7 11.6 12 10 3.6 1.3 0.05 7 12.3 10.3 6.92 10 4.4 5.6 0.07 7 4.3 0.05 0.02 10 5.2 3.5 3.5 7 3.4 0.02 10 1.7 0.24 0.01 7 3 0.01 10 11.3 24 0.7 7 4.1 0.19 0.01 10 1.8 0.04 0.01 7 4.2 0.09 10 10.8 66 8.4 7 5.8 0.12 10 2.4 0.12 0.01 7 6.2 0.23 0.08 10 4.7 5.1 0.01 7 2.6 0.01 10 17.5 146 75 7 3.1 0.03 10 1.1 0.04 0.01 d-68-l/94-A-11 10 13.3 36 11 10 7.2 3.3 0.27 11 7.3 1519.88 526.89 10 15.3 82 42 11 8.7 1.6 1.2 0 1.4 0.03 0.01 11 11.8 30 7.4 195 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 0.8 0.01 0.01 11 10.7 7.8 3 1 1.5 0.03 0.01 11 5 1.3 0.55 0.7 0.01 0.01 11 11.9 22 9 0.9 0.07 0.01 11 12.6 32 11 0.8 0.04 0.01 11 12 12 7 0.7 0.03 0.01 11 9 3 0.06 1 1.6 0.02 0.01 11 10.2 5.6 0.48 0.5 0.01 0.01 11 9.3 3.5 1.4 1 1.2 0.02 0.01 11 10.1 7.6 1.8 7 8.2 5.9 0.1 11 11.9 12 7.7 6 ' 4.4 1 0.1 11 12.2 25 4 6 4.1 0.07 0.01 11 8.6 8.9 3.1 7 13 27 12 11 12.6 29 13 7 2.2 0.28 0.01 11 9.4 5.5 1.6 0 2.4 0.05 0.01 11 4.6 7.1 0.01 0 1.6 0.02 0.01 11 7.9 11 0.04 0 1.4 0.05 0.01 11 7.3 3.2 0.6 0 1.3 0.01 0.01 11 10.7 11 3.2 0 1.3 0.02 0.01 11 12 21 13 0 1.8 0.04 0.01 11 11.8 28 7.8 0 2 0.04 0.01 11 12.7 32 15 0 1.9 0.01 0.01 11 11.5 21 2.1 d-6-A/94-A-14 11 9.9 4.3 2 11 9.5 18 0.64 11 9.9 7.92 0.36 11 8.9 3.5 2 11 7.6 6.06 0.79 11 10 13 0.77 11 10 8.7 0.87 11 8.7 4.7 0.78 11 8.1 5.23 0.96 11 7.5 8.1 0.85 11 6.4 2.46 0.06 11 7.4 5.5 0.49 11 6.6 1.31 0.07 11 10.6 18 15 11 5.3 0.53 0.1 11 8.2 9 0.14 11 9.8 0.05 1.29 11 4.7 0.24 0.01 11 10.5 11.4 0.16 11 10.3 6.3 2.7 11 6.7 0.39 0.24 11 10.5 8.8 3.3 11 9.2 8.02 0.17 11 9.4 3.6 2.2 11 11.8 12.1 2.14 11 10.1 7 3 11 11.1 4.48 0.48 11 9.5 2.6 0.99 11 11.4 13.3 1.02 11 9.7 3.7 1.7 11 10.5 7.47 0.56 11 3.4 1 0.01 11 10.2 6.39 0.36 11 10.6 9.2 7.3 11 10.8 12 0.68 11 9.9 5.2 1.6 11 10.8 13.1 11 5.6 3.8 0.01 11 14 34.2 23.2 11 1.6 0.02 0.01 11 12.7 21.5 23 11 10.1 5.2 1.9 11 5.6 2.74 0.04 11 11.5 11 6 11 13.4 51.1 24.5 11 11.7 13 9.1 11 4.3 2.23 0.02 11 11.4 9.8 4.3 196 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 11 13 43 29.3 11 11.2 6.9 3.5 11 14 33.1 6.9 11 11.3 9.4 3.6 11 11.5 10.8 1.55 11 10.3 3.8 0.81 11 15.3 47.4 25.5 11 8.7 1 0.33 11 15.1 39.1 28.2 11 3.4 0.73 0.07 11 14.4 37.3 18.4 11 9.6 2.8 0.72 11 15.4 54.2 34.4 11 7.8 1.7 0.41 11 14.7 38.2 21.3 11 10.9 5.4 3.1 11 14.1 47.6 11 10.2 3.1 1.2 11 12.5 26.7 11 11.3 9.3 3.8 11 14.7 38 17 11 3.2 0.07 0.04 11 15.1 40.7 19.6 11 10.3 3.4 0.81 11 14.9 41.6 9.93 11 8 11 0.01 11 13.8 29.9 4.96 11 6.4 1 0.01 11 13.6 30.8 15 11 7.6 0.64 0.22 11 12 11 1.89 11 11.3 11 6.4 11 12.8 11.8 5.6 11 10.9 16 2.5 11 13.7 25.8 9.17 11 7.3 1.5 0.2 11 9.3 5.64 2.14 11 3.6 0.3 0.01 11 7.6 0.87 0.51 11 4 0.57 0.05 11 9.2 3.17 1.33 11 3.1 0.16 0.01 11 7.5 1.3 0.31 11 4.4 0.14 0.03 11 6.6 0.37 0.25 11 5.4 0.28 0.05 11 7.9 1.11 0.91 11 6.7 0.51 0.3 11 7.1 0.41 0.12 11 5.6 0.24 0.04 11 9.1 3.21 1.43 11 7.8 1.4 0.95 11 8.5 1.94 0.97 11 2 0.12 0.01 11 7.9 1.36 0.35 11 3.7 0.11 0.02 11 9 2.53 1.42 11 6.9 0.65 0.36 11 10 4.78 1.26 11 1.5 0.01 0.01 11 10.5 5.77 3.07 11 2 0.14 0.01 11 9.3 3.75 0.53 11 2.2 0.12 0.03 11 9.1 3.83 0.59 11 4 0.39 0.06 11 8.3 1.83 0.64 11 6.3 1.6 0.53 11 9.9 4.22 3.97 11 9 2.2 1.5 11 8.8 1.8 1.26 11 2.9 0.06 0.04 11 6.8 0.36 0.19 11 5.1 0.19 0.11 11 6.5 0.2 0.15 0 3.2 0.19 0.02 11 6.5 0.26 0.33 0 2.2 0.26 0.01 11 6.6 0.38 0.3 0 2.7 0.15 0.01 11 6.5 0.35 0.27 d-86-l/94-A-11 11 6.6 0.96 0.19 11 8 1.8 0.56 6 12.7 11 11 5.9 0.57 0.03 6 6.9 0.13 0.01 11 8.8 4.23 1.05 6 7 0.17 0.04 11 6.8 1.07 0.52 6 6.4 4.2 0.11 d-76-l/94-A-11 6 4.8 0.2 197 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 6 4.5 0.08 0.02 10 16.2 194 6 8.8 9.9 0.07 10 17.2 121 6 7.3 0.14 0.11 10 9 17.1 6 10.2 0.3 10 13.3 0.24 6 3.7 0.07 0.04 10 6.1 0.16 6 5.3 0.11 0.04 0 7.4 0.68 6 8.7 16 0.57 b-26-D/94-A-14 11 12.2 24 11 13.6 35 0.45 11 11.4 117 46.9 11 11.4 20 0.98 11 12.4 61.9 39.8 6 7.2 1 0.01 11 9 35.6 11 6 4.6 0.16 11 5.1 14 0.52 6 6.8 0.08 0.04 11 8.4 34.7 28 6 5.6 0.13 0.03 11 5.7 21 17.4 6 5.4 0.11 0.01 11 6.8 36.2 24 6 6 0.18 11 7.1 28.4 3.54 11 6.3 6.14 0.03 11 7.6 41.5 23.3 11 6.1 0.72 0.02 11 7.3 9.8 6.88 11 10.7 23.04 0.22 11 7.2 27.4 14 11 6.9 0.45 11 5.5 32.2 7.32 11 12.6 31 0.75 11 11.3 77.7 72.8 11 10.2 11 0.3 11 8.3 39.7 35.9 11 10.9 12 2.4 11 10.4 51.2 46 11 5.8 0.14 11 9.1 38.6 27.4 11 7.2 4.7 0.06 11 6 30.4 1.42 11 9.2 4.5 0.36 11 7.9 45.9 13.5 11 6.7 14 0.13 11 12.5 187 141 11 16.1 71 11 8.9 69.3 61.8 11 10 22 0.1 11 13.6 138 137 11 9.7 6 0.31 11 10.4 50.2 32.3 11 5.4 2.1 0.03 11 7.1 47.3 36.6 11 4.1 0.98 11 12.9 102.5 99.1 11 7.4 8 0.04 11 10.9 67.8 53.5 11 11.1 19 0.2 11 7 55.9 0.54 11 9.9 9.9 0.56 11 7.2 43 0.48 11 8.4 0.14 11 9.7 48.6 22.6 11 8.3 0.61 0.08 11 10.9 64.2 41.6 11 5.8 1.4 0.08 11 6.6 17.6 1.29 11 13 23 1.3 11 10 32.8 32.6 11 16.8 71 11 8.3 36.2 23.1 11 7.4 16 0.04 11 9.2 90.6 27 11 5 11 0.04 11 12.4 105 98.4 11 15.5 35 9.6 11 11 96.6 63.2 7 12 3.1 11 10.6 78.7 66.7 7 15.2 37 17 11 8.8 188 47.7 7 1.8 0.12 0.01 11 10.3 76.7 14.7 7 5.8 28 0.01 198 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 11 11.9 20.8 8.48 7 8.6 0.42 11 6.3 78.6 0.4 7 4.5 2.2 0.01 11 9.3 37.4 14.8 7 12.8 20 11 11 9.4 46.7 17.4 7 14.1 33 19 11 13.7 90.3 0.19 7 8.8 1.6 11 4.3 2.2 0.13 7 4.4 0.4 0.01 11 4.4 7.23 3.26 7 8.2 5.7 0.16 11 4 3.81 0.96 7 10.3 9.4 2.4 11 5.4 17 10.7 7 8.6 0.9 11 14.5 70.6 7 12.6 25 18 7 1 0.06 0.05 7 9.1 6.5 3.6 D-64-I/94-A-12 7 11.3 12 2.3 0 11.1 6.4 11 2.9 1215.9 60.79 0 2.3 0.15 0.01 11 9.5 11 0.77 0 3 0.29 0.01 11 0.6 0.02 0 6.3 0.32 11 0.1 0.13 0 4.7 0.39 0.01 11 0.1 0 2.8 0.08 0.01 11 0.1 0.06 0 9.6 2.5 11 0.7 0.04 0 6.2 0.45 11 6.5 26 0.21 D-6-D/94-A-14 11 16.5 98 76 11 15.3 65 52 11 6.6 33437.25 10.13 11 13 50 27 11 9.2 38.8 0.1 11 9.9 20 2 11 12.9 30.9 11 0.3 0.01 11 4 2.29 0.14 C-80-L/94-A-11 11 9.4 51.5 2.52 11 17.2 281 87.6 9 1.4 0.12 0.01 11 18.4 171 9 3 0.28 0.03 11 9.8 72.1 0.06 9 1.5 0.14 0.07 11 7.1 15.5 2.6 9 2.9 0.15 0.05 11 7.8 49 0.09 9 3.5 0.25 0.05 7 6.1 7.45 0.25 9 1.3 0.03 0.03 7 4 5.91 0.26 9 2.2 0.01 0.01 7 11 20.6 2.22 9 2.2 0.3 0.04 7 14 22.8 9 2.4 0.09 0.04 11 2.3 0.08 0.02 9 2.7 0.24 0.04 11 9.2 6.59 1.52 9 1.9 0.17 0.1 7 1.2 0.05 9 1.9 0.24 0.07 7 5.2 0.14 9 2.2 0.01 0.01 0 1.1 0.08 1 1.4 0.02 0.02 d-42-H/94-A-13 1 0.5 0.02 0.02 1 1.4 0.02 0.02 11 5.2 0.6 0.11 1 1.5 0.03 0.03 11 4.8 0.37 0.08 0 9 0.15 0.09 11 6.1 0.67 0.22 1 2.7 0.09 0.03 11 4.1 0.48 0.02 199 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 1 3.6 0.12 0.06 11 9 5.82 1 2.7 0.09 0.09 11 7.1 1.94 0.26 0 2.1 0.07 0.07 11 6.2 0.54 0.14 1 1 0.08 0.03 11 6.9 0.64 1 1.4 0.34 0.07 11 4.5 0.16 0.02 1 1.7 0.3 0.06 11 6.1 1.14 0.46 1 1.3 0.35 0.03 11 6.9 0.49 1 1.2 1 0.07 11 7.6 1.02 0 2 1.5 0.02 11 5.6 0.59 0.21 0 1.7 0.4 0.01 11 7.5 1.08 1 0.5 0.06 0.01 11 5.4 0.77 0.06 1 0.5 0.2 0.02 11 6.8 0.69 1 0.5 0.12 0.12 11 7.3 0.74 1 0.5 0.14 0.07 11 6.5 0.34 1 2.2 1.2 0.01 11 3.4 0.07 0.01 a-66-l/94-A-10 11 4.1 0.37 0.03 11 5.6 0.81 0.35 11 6.7 0.11 11 6.8 0.77 11 3.1 0.02 11 7.8 0.75 11 11.6 1.39 11 3.8 0.19 0.04 11 12.5 6.83 3.4 0.09 0.02 11 12.7 7.87 11 3.8 0.15 0.06 11 14.4 5.16 1.8 0.03 0.02 11 13.5 7.79 3.6 0.12 0.05 11 17.1 68.4 11 6.7 0.54 0.17 11 16.1 84.3 11 6.3 1.02 0.25 11 15.4 57.9 11 2.9 0.37 0.02 11 15.8 47.3 11 8 2.18 11 11.7 11.1 11 7.9 2.74 11 8.3 0.54 11 7.8 2.5 11 8.6 0.86 11 5.9 1.21 0.16 11 6.4 0.22 11 3.5 0.09 0.07 11 6.9 0.19 10-13-79-21W6 11 8 0.88 11 6.6 0.19 11 4.1 10.13 11 7.2 0.26 11 2.7 0.03 11 10.2 1.89 11 1.5 0.03 11 8.7 0.87 11 2.9 0.01 16-34-82-16W6 11 2.4 0.01 11 2.3 0.01 11 10.2 3.3 3.1 11 2.3 0.01 11 11.2 4 4 11 2.3 0.01 11 11.1 3.9 3.3 13 2.4 0.01 11 11.5 5.6 3.8 11 9.8 8.04 11 11.7 3.9 3.5 12.2 0.03 11 11.1 3.9 3.2 11 12.2 0.03 11 11.1 5.1 4 11 10.4 20.9 200 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 11 10 3.9 3.6 11 12.2 0.63 11 10.1 2.8 2.5 11 10.4 20.9 11 9.8 3.1 2.9 11 3.4 0.03 11 9.3 3.9 3.7 11 8.8 20.6 11 10.5 4.2 3.8 11 3.7 0.01 11 10.8 8.9 8.1 11 10.4 20.9 11 11.4 9.8 9.4 12-01-078-14W6 11 11.7 3.9 2.7 11 10.1 1.6 0.81 11 10.7 7.9 11 10.6 2.8 1.1 11 10 11.7 11 9.8 2 1.2 11 10.1 15.7 11 10.8 2.9 1.5 11 7.7 1.15 11 10.4 0.9 0.4 11 9.3 1.34 11 10.5 4 2.3 11 8.4 14 11 10.8 5.1 2.3 11 8.9 0.91 11 10.9 8.7 1 7 2.5 0.13 11 12 10 2.9 7 8.2 0.63 11 10.2 5.8 3.6 7 10.3 10.62 11 10.3 4.5 0.69 7 8.9 11.57 11 6.9 2.6 0.13 7 9.7 2.51 11 8.5 0.61 11 9.3 1.86 11 7.7 3.6 0.18 11 9.2 2.92 11 10.2 3.1 0.87 11 10.3 10.41 11 9.4 3.1 0.17 11 10.5 16.59 11 9 2.4 0.25 11 9.8 5.93 11 6.9 0.95 0.36 11 10 1.54 11 7.6 1.58 0.06 11 9.4 1.96 11 8.2 2.9 • 0.42 11 10.3 13.96 11 9.5 1.8 0.69 11 10.1 16.46 11 7.2 1 0.18 11 9 0.93 11 9.3 4.1 1.3 11 9.9 13.87 11 8 1 0.86 11 10.2 10.93 11 10.4 2.4 1.8 11 10.4 10.59 11 9.5 1.6 0.69 11 10.6 20.53 11 8.9 2.1 0.56 11 8.1 2.66 11 9.2 1.9 0.54 11 10.2 7.68 11 9.1 1.5 0.55 11 9 3.96 11 10 2 0.99 11 9.7 1.15 11 8.9 1.2 0.6 11 8.4 1.23 11 8.5 1.1 0.24 11 9.9 6.48 11 9 1.6 0.86 11 9.7 19.71 11 8.9 1.9 0.06 11 10.2 10.82 11 4 2.6 0.05 11 9.9 8.73 11 5.6 0.96 11 9.2 8.6 11 6.5 0.48 0.06 11 9.1 1.8 11 2.1 2.7 11 8.8 3.12 11 4.5 2.8 0.1 11 9.1 1.68 201 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 11 7.6 2.1 0.93 11 9.8 11 6.6 0.8 0.3 06-07-79-20W6 11 7.7 3.2 0.46 11 9.3 4.4 2 11 3.2 0.03 11 9.3 2.8 0.48 11 2.7 0.02 11 9.5 2.5 0.8 11 2.1 0.01 08-18-80-17W6 11 2.8 0.03 11 3.2 0.03 0.01 11/7 5.8 0.03 11 3.7 0.03 11/7 4.9 0.02 11 5 0.11 0.03 11/7 7.1 0.15 11 4.1 0.06 11/7 7.9 0.29 11 1.1 11/7 7 0.12 11 4.9 0.05 11/7 5.7 0.07 11 5.1 0.09 0.04 11-29-87-21W6 11 3.6 0.1 10-36-87-22W6 6 2.2 0.11 0.01 6 7.9 1.08 0.01 11 5.4 0.2 10 2.4 0.27 0.01 11 2.9 0.07 10 2.3 12 0.01 11 3.1 0.08 10 7.4 0.88 0.03 11 2.2 0.04 10 1.4 4.27 0.01 11 1.7 0.04 10 1.4 0.75 0.03 12-35-87-22W6 10 5 20.4 0.01 10 6.7 0.06 0.01 10 4.4 0.35 0.05 10 16.5 304 128 10 5.8 3.86 10 5.1 9.03 11.4 10 7.8 1.9 10 4.1 7.09 0.03 10 5.5 2.47 0.03 6 5.9 0.1 0.01 10 12.9 74 11 3.5 9.05 0.05 10 14.9 99.1 33.4 11 5.9 0.1 0.01 10 12.8 43.2 11 3 0.11 0.01 4 12.8 0.19 11 12 44.1 6.7 4 8.3 0.86 0.05 11 11.7 34.9 4.15 4 5.9 4.24 0.06 10 9.6 13.6 2.15 11 8.2 2.83 0.92 10 3.6 0.05 0.01 11 6.5 35.7 0.25 10 9.4 16.5 1.57 11 8.9 0.46 10 3.6 0.05 0.01 4 4.3 3.95 0.01 10 12.1 48 12.5 4 4.6 32 0.12 10 0.5 0.04 0.01 4 5.3 2.42 0.14 11 11.2 31.5 7.26 11 2.9 0.02 , 0.01 11 8.5 7.02 3.48 11 3.7 3.79 0.07 11 2.5 0.17 0.01 11 3.8 1.27 1.23 15-21-87-20W6 11 17.3 155 104 11 17.3 349 7 10.3 0.2 11 14 228 7 7.3 0.19 0.09 11 1.9 0.03 0.01 202 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 7 9.2 0.19 11 10.3 20.6 0.18 7 2.8 0.09 0.05 10 14.6 41.2 10 12.1 0.72 10 7.9 56.9 0.08 10 4.2 0.19 0.14 10 9.5 59.2 12.9 10 11.9 0.43 10 10.1 7.5 10 12.7 1.7 0.19 10 12 9.37 10 10.7 0.54 10 10.4 37.2 10 5.9 0.3 0.09 10 8.4 2.35 0.55 10 7.7 0.2 10 3.4 28.5 10 2.7 0.11 0.07 10 7.7 0.45 10 1.6 0.12 0.04 10 8.6 27.2 0.56 10 11 0.56 6 9.6 3.48 10 3.9 0.12 0.04 6 7.2 12.8 0.27 10 6.2 0.94 0.05 6 6.5 25.2 0.14 10 12.2 0.5 6 12.5 139 0 0.8 0.03 0.03 6 8.1 74.2 0.08 12 0.3 0.83 0.02 10 3.8 4.55 0.04 12 0.3 0.24 0.05 10 4 14.6 0.1 6 7.1 0.15 0.03 10 5.3 8.65 0.7 6 7.5 0.25 10 4.2 0.74 6 12.6 3.4 10 5.2 5.3 0.08 6 6.4 1.6 0.1 10 7.7 20.5 6 7.1 3.7 0.89 10 5.1 34.3 6 4.8 0.39 10 3 2.85 0.17 6 3.3 0.36 0.09 10 7 4.54 0.05 6 0.6 0.07 0.02 10 7.7 0.83 6 1.9 0.09 10 5.6 0.08 11 7.7 1.9 10 4.8 0.29 0.05 11 1.7 0.09 0.02 10 4.6 22.1 11 4.7 0.11 11 6.1 28.3 17.4 11 5 0.13 01-05-88-21W6 11 3.5 0.17 0.05 11 3.1 0.12 11 1.8 0.06 0.01 11 5.3 0.34 11 18.7 217 227 6 5.6 1.1 11 16.5 58.9 30.2 6 4.6 0.14 0.05 11 1.6 0.07 0.02 6 8.1 6.4 0.84 11 10.6 15.5 6.24 6 9 0.56 11 13.3 18.7 13.7 6 5.8 2.2 0.16 11 4.4 0.99 0.05 6 7.1 0.15 11 8.8 4.12 1.84 11 3 0.09 0.08 11 4.4 0.99 0.05 10 5.4 0.23 11 7.9 3.11 1.36 10 5.9 0.61 11 4.4 0.99 0.05 10 5.1 6.5 0.28 11 7.9 3.77 1.24 10 5.4 2.9 0.06 11 2.1 0.99 0.02 11 5.1 0.15 10 5.5 1.24 0.06 11 5.3 2.6 0.6 10 14.6 22.7 15.6 203 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 11 1.8 0.06 0.03 10 3.9 8.44 0.03 11 5.3 0.16 10 14.7 22.7 15.6 10 5.6 4.5 0.14 6 6 0.29 0.01 10 8.3 2.5 11 14.6 22.7 15.6 10 3.7 0.08 11 16 66.5 93.4 10 2 0.16 0.05 11 11.4 13.3 1.89 10 3 0.13 11 7.8 1.9 0.07 10 1.5 0.07 0.02 0 3.1 6.59 0.01 10 2.8 0.09 0 3.1 0.03 0.01 02/06-04-86-20W6 11 2.5 0.13 0.01 11 5.5 1.9 0.24 1 0.1 0.03 0.01 7 1.3 0.03 0.01 1 0.2 0.01 0.01 7 3.4 0.09 0.01 1 0.1 0.01 0.01 0 2.7 0.02 0.01 0 0.3 0.02 0.01 0 3 0.03 0.01 1 0.1 0.01 0.01 04-03-88-22W6 1 0.5 0.01 0.01 11 1.1 0.02 0.01 11 0.8 0.05 0.02 11 3.5 0.11 0.09 0 9.3 9.67 3.79 11 2.5 0.09 0.06 0 8 2.51 1.24 11 4.8 0.2 0.05 11 2.7 0.06 0.02 11 9.5 3.4 0.69 11 0.8 0.03 0.01 11 3.8 0.85 0.04 11 13.2 88.8 6.35 11 5.4 1.9 0.03 11 2.7 2.29 0.04 11 12 24 4.9 11 11.4 39.6 1.63 11 6.7 2.1 0.52 11 2.7 2.29 0.04 11 4.5 3 0.65 11 14.4 133 85.3 11 4.3 2.2 0.01 11 16.6 181 76.3 11 10 8.4 11 12.4 33.8 3.28 11 13.9 26 2.7 11 11.2 35.7 1.05 11 10.5 15 0.06 11 6.9 31 0.07 11 9.5 11 0.1 11 13.6 150 72.6 11 9.5 4.8 1.6 11 11.5 70.9 3.3 11 9.5 7.9 0.81 11 15.2 127 36.4 11 0.4 0.07 0.03 11 14.6 165 46 11 1.4 0.16 0.09 11 1.8 0.08 0.03 1 1.2 0.01 0.01 11 3.7 0.62 0.03 1 1.5 0.01 0.01 11 1 0.02 0.03 1 0.7 0.02 0.01 11 12.6 187 52.3 1 2 0.01 0.01 11 1.7 12.9 0.03 d-73-F/94-G-9 11 12.6 187 52.3 11 10.6 89.1 36.1 11 7.3 0.4 0.29 11 5 14.2 0.55 11 6.1 0.25 0.13 11 1.4 0.26 0.05 11 6.4 0.34 0.14 d-91-G/94-G-9 11 5.7 0.05 0.01 11 7.6 0.42 0.04 7 9.6 1.1 0.2 204 FACIES Porosity (%) Kmax (mD) Kv (mD) FACIES Porosity (%) Kmax (mD) Kv (mD) 11 7.4 0.5 0.07 7 14.1 0.39 0.06 11 7.3 0.71 0.19 7 9.4 0.42 0.01 11 9.7 16 0.43 7 8.5 0.18 0.01 11 10.2 16 2.6 7 9 0.57 0.01 11 5.9 0.19 0.01 7 4 0.18 0.01 11 5.5 0.09 0.01 7 3.3 0.08 0.03 11 4.4 0.05 0.01 10 1.7 0.05 10 2.2 0.04 10 1.7 0.05 10 2.2 0.04 10 2 0.05 10 2.3 0.05 10 2 0.05 10 2.6 0.05 10 1.9 0.04 10 1.9 0.04 10 2.1 0.04 10 1.9 0.04 10 3.1 0.06 10 6.1 0.1 205 

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