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UBC Theses and Dissertations

Mineralogy and computer-orientated study of mineral deposits in Slocan City Camp, Nelson Mining Division,… Orr, John Frederick Walter 1971

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MINERALOGY AND COMPUTER-ORIENTATED STUDY OP MINERAL DEPOSITS IN SLOCAN CITY CAMP, NELSON MINING DIVISION, BRITISH COLUMBIA by JOHN F. W. ORR B.Sc. 1968 University of British Columbia A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in the Department of Geology We accept" this thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA May, 1971 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of Brit ish 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 representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of The University of Brit ish Columbia Vancouver 8, Canada X . ABSTRACT Slocan City mineral deposits are "dry" fissure types (Cairnes, 1934, p.114) consisting of high grade silve r veins i n quartz, with minor amounts of lead and zinc. These veins, almost a l l i n Nelson plutonic rocks, occur i n an area of approximately 100 square miles along the eastern margin of Slocan Lake. Mineralogical analysis revealed a definite concentric zoning i n the camp; a pyrite halo with high gold values surrounds a core of galena and sphalerite with high silve r values. The most commonly occurring minerals i n order of deposition are: pyrite, sphalerite, chalcopyrite, gold, tetrahedrite, galena, silver, ruby silvers, and argentite. Quartz i s the dominant gangue mineral, with small amounts of calcite, siderite, barite, and fluorite generally concentrated i n the central zone. Publically available production data for 73 mineral deposits, and geological and mineralogical data obtained from f i e l d and laboratory studies,were organized i n a computer-processible data f i l e . Methods used to investigate the usefulness of such a f i l e for both academic and practi-cal purposes include: computer generated plots and contour maps, correla-tion studies, trend surface analysis, multiple regression, and chi square analysis. Computer contour plots and trend surface analysis were rapid means of analyzing lateral zoning of average metal grades and ratios. Patterns obtained substantiated the mineral zoning which was based on data from appreciably fewer mineral deposits. Multiple stepwise i i regression showed that value of a deposit (estimated by total production in tons) is dependent on average grades of lead and zinc, and volume percentage total sulphides. Consequently, the tonnage potential of a prospect might be predictable within specified limits from a single bulk sample and a brief geological examination. Chi square analysis showed that relatively large deposits are characterized by a more-or-less north-easterly strike and the presence of small amounts of barite and carbonate gangue. The ease and rapidity with which proven statistical techniques can be applied to the mass of informal ion in a computer-processible data f i l e gives great scope and practicality to the concept. i i i TABLE OP CONTENTS CHAPTER PAGE I INTRODUCTION I PURPOSE OF STUDY I PHYSICAL SITUATION I NATURE OF DEPOSITS 3 FIELD METHODS 4 HISTORY OF SLOCAN CITY CAMP 7 RECENT ACTIVITY 8 II MINERALOGY OF SLOCAN CITY DEPOSITS 10 GENERAL GEOLOGY 10 CLASSIFICATION OF DEPOSITS 11 ANALYSIS OF SAMPLES 12 ORE MINERALOGY 13 SUPERGENE MINERALOGY 28 GANGUE MINERALOGY 29 VERTICAL ZONING HYPOTHESIS 39 CONCLUSIONS 41 III DEVELOPMENT OF A COMPUTER-PROCESSIBLE DATA FILE FOR SLOCAN CITY MINERAL DEPOSITS 46 INTRODUCTION 46 SLOCAN CITY DATA FILE 49 IV ANALYSIS OF SINGLE VARIABLES 57 INTRODUCTION 57 SLOCAN CITY UNVARIANT DATA 59 V COMPUTER PLOTS 59 INTRODUCTION 69 VEIN ORIENTATION PLOT 69 MINERALOGY PLOTS 74 i v . CHAPTER PAGE VI MACHINE CONTOURED PLOTS OF METAL GRADES AND RATIOS 76 INTRODUCTION 76 APPLICATION TO SLOCAN CITY DATA FILE 77 DISCUSSION 88 VII TREND SURFACE ANALYSIS 90 INTRODUCTION 90 METAL ASSAY TREND SURFACES 93 SUMMARY 120 VIII MULTIPLE REGRESSION ANALYSIS 123 INTRODUCTION 123 ESTIMATE OF SLOCAN CITY MINE VALUE 124 IX CHISQUARE ANALYSIS 129 INTRODUCTION 129 CHI SQUARE ANALYSIS OF SLOCAN CITY DATA FILE 131 CONCLUSIONS 135 X SUMMARY AND CONCLUSIONS 136 BIBLIOGRAPHY 141 LIST OP TABLES Page Table I Identification and Tonnage for 73 Slocan City Mines 6 Table II Average Mineral Percentages, Slocan City Ores 11 Table III Correlations and Error Measures for Equations of a l l Variables compared to Elevation 40 Table IV Coding System Slocan City Data F i l e : Card One 52 Table V Coding System Slocan City Data F i l e : Card Two 54 Table VI Means and Standard Deviation of Arithmetic and Logarithmic Values of Variables 67 Table VII Correlations of Mineralogy and Metal Grades 78 Table VIII Trend Surface Accuracy Measures 92 Table IX Equations and Data for Silver Trend Surfaces 94 Table X Equations and Data for Lead Trend Surfaces 98 Table XI Equations and Data for Zinc Trend Surfaces 102 Table XII Equations and Data for Gold Trend Surfaces 106 Table XIII Equations and Data for Lead/z inc Trend Surfaces 110 Table XIV Equations and Data for Gold/Silver Trend Surfaces 114 Table XV Equations and Data for Silver/Lead Trend Surfaces 117 Table XVI Correlation Matrix of Logged Variables 124 Table XVII Contingency Table of Rock Type versus Deposit Type 129 Table XVIII Contingency Table of Deposit Size versus Dykes 132 Table XIX Contingency Table of Deposit Size versus Wall Rock 133 Table XX Contingency Table of Deposit Size versus Gangue 134 Table XXI Contingency Table of Deposit Size versus Vein Orientation 134 LIST OF FIGURES Page Figure 1 - Location and Geology of Slocan City Mining Camp 2 Figure 2 - Mine Site Locations 5 Figure 3 - Contoured Pyrite Distribution 15 Figure 4 - Contoured Sphalerite Distribution 17 Figure 5 - Contoured Chalcopyrite Distribution 19 Figure 6 - Contoured Galena Distribution 20 Figure 7 - Contoured Tetrahedrite Distribution 22 Figure 8 - Contoured Native Silver Distribution 24 Figure 9 - Contoured Argentite Distribution 26 Figure 10 - Photomicrograph of Argentite and Native Ag, Meteor mine 32 Figure 11 - Photomicrograph of Galena and Freibergite, Hampton Mine 32 Figure 12 - Photomicrograph of Sphalerite with Chalcopyrite, Slocan Bob Mine 33 Figure 13 - Photomicrograph of Galena, Tetrahedrite, and Chalco-pyrite, Enterprise Mine 33 Figure 14 - Photomicrograph of Chalcopyrite, Argentite, Gold, and Sphalerite, Ottawa Mine 34 Figure 15 - Photomicrograph of Argentite and Chalcopyrite, Tamarack Mine 34 Figure 16 - Photomicrograph of Sphalerite, Chalcopyrite, Tetra-hedrite, and Electrum, Coronation Mine 35 Figure 17 - Photomicrograph of Galena with Freibergite, Kalispell Mine 35 Figure 18 - Photomicrograph of Magnetite with Hematite, V&M Mine 36 V l l . Page Figure 19 - Photomicrograph of Galena "Halo", Enterprise Mine 36 Figure 20 - Photomicrograph of Ruby Silver and Argentite, Goldstream Mine 37 Figure 21 - Photomicrograph of Native Silver and Galena, Black Prince Mine 37 Figure 22 - Photomicrograph of Tetrahedrite, Chalcopyrite, Sphalerite, and Galena, L i t t l e Tim Mine 38 Figure 23 - Photomicrograph of Pyrrhotite, Marcasite, and Sphalerite; Hope #2 Mine 38 Figure 24 - Van der Veen Diagram of Paragenesis 42 Figure 25 - Bar Graph Diagram of Paragenesis 42 (a) Figure 26 - Diagrammatic Cross-section of Inferred Mineral Zonation Pattern 44 Figure 27 - Cumulative Probability Graph of Average Silver Grades 58 Figures - Histograms of Arithmetic and Logarithmic values for 60 28 - 33 Tonnage, Silver, Lead, Zinc, Gold, and Volume fo of to 65 Sulphides Figure 34 - Vein Orientation Plot 70 Figure 35 - Contoured Stereonet Plot of Fissure Orientations 72 Figures - Computer Contoured Plots of Silver, Lead, Zinc, 80 37-40 and Gold to 83 Figures - Computer Contoured Plots of Silver/Lead, Lead/Zinc, 85 41 - 43 and Gold/Silver to 87 Figures - Silver Trend Suifaces 95 44 - 46 to 97 Figures - Lead Trend Surfaces 99 47 - 49 to 101 Figures - Zinc Trend Surfaces 103 50-52 to 105 Figures - Gold Trend Surfaces 107 53 - 55 to 109 COLUMNS DESCRIPTION 1-4 Location number, keyed to Camp and Map Position 5-13 Alphanumeric name 14-19 X and Y coordinates, UTM System 20-23 Elevation of main workings above sea level 24-25 Total years of production 26-32 Total recorded production, i n tons 33 Replacement ""N 34 Conformable Fissure ^ ColeV^T^Ljor 35 Cross-cutting Fissure j 2 - Minor r,r • T J I 3 - Present 36 Massive Lode J 37 Quartzite " ~~ 38 A r g i l l i t e 39 Limestone 40 Nelson Granite 41 Porph. Nelson Granite 42 Kaslo Greenstones Host Rock Coded by 1 - Major 2 - Minor 3 - Present 43 Lamprophyre and basalt dykes 44 Aplite dykes 45 Quartz Proph/pegmatite dykes 45-51 Fissure Orientation 52-55 Silver Oz/ton 56-59 Lead, # 60-63 Zinc, fo 64-68 Gold, oz/ton 69-72 Cadmium, #/ton 73-76 Copper,'#/ton 77-78 Year of latest production 79 Classification of deposit as wet,dry anomalous, or float -after Cairnes 80 Unassigned Table IV. Coding System Slocan Data F i l e , Card #1. v i i i . Page Figures - Lead/Zinc Trend Surfaces 111 56 - 58 to 113 Figures - Gold/Silver Trend Surfaces 115 59 - 60 to 116 Figures - Silver/Lead Trend Surfaces 118 61-62 to 119 Figure 63 - Idealized Composite Diagram of Inferred Zonal Distribution 122 Figure 64 - Scatter Diagram of Expected versus Observed Tonnages 128 ix. ACKNOWLEDGEMENTS The writer wishes to acknowledge financial support by grants from the Geological Survey of Canada, and Cominco Ltd. Supervision and moral support of the writer by Dr. Alastair Sinclair was v i t a l i n completion of the thesis. Mr. James G. Lawrence ably assisted i n the f i e l d work. Mr. Melvin H. McKortoff volunteered his help i n enlarging and photor graphic work. Discussion with experienced geologists and mine personnel of the di s t r i c t including: Mr. Prank Mills (former manager of Galena Farm), Mr. Stan Pedley (former manager of the Victor), Mr. Van Hansen (operating the Freddy), and Mr. Adrian Kessler (miner and prospector l i v i n g i n Silverton); aided the writer appreciably. Much assistance was obtained from employees of the B.C. Department of Mines and Petroleum Resources, at their offices i n Vancouver, Nelson, and Kaslo. Technical assistance in programming by Mr. Leo Fox i s gratefully appreciated. A l l computations were done using IBM 360/67 model computer, at the University of British Columbia. Mrs. Maria Orr and Mrs. Alexis Clague did excellent typing and c l e r i c a l work in preparation of the thesis. 1. CHAPTER ONE INTRODUCTION PURPOSE OF STUDY This investigation was conceived to yield a case history of the usefulness of computer-processible f i l e s i n examining geological and assay data from an established mining camp with numerous mineral deposits. The project had two general aims: (l) to develop a computer-processible f i l e containing both published assay data and f i e l d data, and (2) to investigate possible academic and practical applications of the data f i l e . The main reason for such a study i s an attempt to mesh rapidly expanding computer technology with analysis of mineral deposits. In particular, the writer was interested i n examining (l) the possibility that computer-oriented techniques might do away with much of the labourious and time consuming procedures used routinely i n studying mining camps, and (2) the potential of numerous methods of data analysis that can be handled ef f i c i e n t l y only by a computer. PHYSICAL SITUATION Slocan City mining camp i s a strip of rugged mountainous terrain roughly seven by fifteen miles, along the eastern shore of Slocan Lake; centred some thirty miles northwest of Nelson, B.C. ( f i g . l ) . Most of the country rock i s a variety of phases of the Nelson batholith, mainly / £v « I \ % \ ; ' \ \ \ -'-i i H ' • ^ a » ^ \ .... . . | ; ) + • Slocan group quartzites, slates, volcanics Valhalla granite , Aylwin Peak - ^ i - . . . + + Imbricate Zone / Horsethief Creek Group Slocan City Area U.S.A. FIGURE I Geology of Slocan City Mining Camp, British Columbia (After Ross and Kellerhals, 1968;Little,I960;and Cairnes, 1934) (Location outlined by inset map) 3. porphyritic granodiorites to quartz monzonites. A granitic augen gneiss (structurally overlying impure arenaceous schists) and the Nelson granites grade into each other i n a "crushed" zone over a distance of about one hundred feet on the western margin of the camp (Ross and Kellerhals, 1968). A few i n l i e r s of Triassic Slocan Group slates and quartzites are scattered i n the batholith. Slocan Group rocks are abundant immediately north of the Nelson batholith where they are the host for mineral deposits of Slocan camp. Prospecting i s d i f f i c u l t ; the country i s covered by thick coniferous forest, with devil's club and alders abundant in moist low areas. Glacial d r i f t mantles the entire camp,except for bedrock exposures along ridges and i n stream beds. NATURE OF DEPOSITS The ores are important for silve r and to a lesser extent gold; with minor amounts of lead and zinc. They occur mostly as quartz-sulphide veins formed by open space fil l i n g , w i t h minor effects of wallrock alteration and limited replacement. The deposits have been classed by Cairnes (1934) as "dry" veins, and are mineralogically distinct from the "wet" vein (massive galena and sphalerite, i n siderite and quartz gangue) deposits of Slocan camp to the north. "Dry" ores are characterized by small tonnages (up to 20,000 tons production), granitic host rock, abundant quartz gangue and a low sulphide content including pyrite, galena,sphalerite, tetrahedrite, chalcopyrite, native gold, and a variety of silver minerals such as 4. argentite, native silver, ruby silvers, stephanite, and others. "Wet" ores are characterized by much larger tonnages (commonly 10,000 - 100,000 tons ore more), Slocan Group metasedimentary rocks as host, prevalence of quartz and a variety of carbonates (siderite, with lesser amounts of calcite and rare dolomite) as gangue, and a high proportion of sulphides (particularly galena and sphalerite) i n veins. This study i s based on the mines of the Slocan City camp that have both recorded production and a known location ( f i g . 2). Their commonly accepted names, and the total shipped ore tonnages produced at any time between 1893 and 1969 are l i s t e d i n Table I. FIELD METHODS A geologist i n the f i e l d tends to assess the potential of a group of claims on the basis of a relatively small number of variables familiar to him. Along with his subjective impressions, however, a s t r i c t l y objective l i s t of facts for each site visited should be f i l e d , diminishing the tendency toward laconic notes such as "same host rock and gangue as last site, many mosquitos, trace unidentifiable sulphides". During the summer of 1970, the writer examined 37 of the 73 mines with recorded production i n Slocan City camp, taping f i e l d data with a Philips cassette recorder. Variables recorded include host rock, dyke rocks, vein and joint orientation, gangue and sulphide mineralogy and abundance, elevations of workings, and wallrock alteration type and intensity around the mine site. Cairnes' map (1934) was used as a primary reference for most of the area, as i t was 5. # ,.2 4«P 6 .7 .9 Aylwin Peak .16 10 70, .22 ,g 2425*26 *27 3 2 * . . 3 4 33 *35 (Cross-Sect ion,F ig .26) J 7 60 .73 •69 • 68 FIGURE 2 Mine S i t e Locations 6. NO NAME TONNAGE NO NAME TONNAGE 1 GET THERE 10 37 PORT HOPE 15 2 GOLDEN 1 38 CRIPPLESTICK 11 3 L.H.GROUP 216 39 MORNING STAR 27 4 ROCKLANDS 331 40 DAYTON 26 5 LITTLE DAISY 51 41 TAMARACK 117 6 SILVER NUGGET 2 42 ALMA 2 7 SILVER LEAP 43 43 OTTAWA 24342 8 HIGHLAND LIGHT 11 44 ANNA (SILVER KING) 195 9 KALISPELL 22 45 LILY B 45 10 WESTMONT & EASTMONT 4391 46 ARLINGTON 15604 11 DUMAC-AUSTIN 40 47 SPECULATOR 29 12 NEEPAWA 506 48 ALICE S 16 13 ENTERPRISE 12274 49 BANK OF ENGLAND 4 14 MABOU & OHIO 8 50 TWO FRIENDS 168 15 RIVERSIDE 22 51 SLOCAN PRINCE 1918 16 PARA-ROYAL 17 52 BLACK PRINCE 1608 17 BOOMERANG 3 53 HAMPTON 100 18 PAYSTREAK 126 54 EXCHANGE 18 19 HAMILTON 38 55 SMERALDA 3 20 HOMESTAKE 148 56 EVENING STAR 95 21 HAPPY MEDIUM 13 57 CALUMET 1 22 SAPPHIRE & CHAMPION 41 58 HOWARD FRACTION 212 23 V AND M 15 59 METEOR 2878 24 BATCHELOR 150 60 MARMION & MARYLAND 48 25 CORONATION 2 61 HOPE NO.2 527 26 COLORADO 27 62 CHAPLEAU 326 27 MYRTLE (ALMA) 83 63 SKYLARK AND RANGER 3 28 CUB 9 64 KILO 2357 29 GRAPHIC AND ROSEBUD 10 65 GOLDSTREAM 40 30 LITTLE TIM 160 66 DUPLEX-JOAN 10 31 BONDHOLDER 72 67 CRUSADER 6 32 BELL No.2 5 68 ORO FINO 18 33 REPUBLIC 242 69 ALPINE 17099 34 SLOCAN BOB 1 70 JOYCE 10 35 CLUB 5 71 B&R GROUP 3 36 GOLD VIKING 40 72 ELK 2 73 BARNETT GROUP 2 Table II. L i s t of Mines and Total Tonnages Produced. 7. invaluable for locating the older workings. There are few passable roads l e f t i n the h i l l s , and most of the travelling was done on foot. Samples of ore and country rock were collected, and, where possible, color slides of outcrops and workings. A l l observations were made by the writer, i n order to provide a relatively uniform quality of f i e l d data. HISTORY OF SLOCAN CITY CAMP The history of the camp extends back to the 1880's, when miners attracted to the Ainsworth or Hot Springs camp to the east prospected the Selkirk Mountains. The f i r s t mines of the boom period of 1890-1910 were worked during the winters, with the ore being skidded out on rawhides by horse. Access t r a i l s , steep winding paths of well-built stonework, s t i l l zigzag up to some of the early adits. A railway was constructed to the north end of Slocan Lake, and sternwheelers plyed the length. Tourists in the thirti e s were told of the "lost mine" on the western shore of Slocan Lake by the captain of one of these ships. It was an outcrop of galena visible from the water, carefully touched up every other voyage by his crew. The rest of the western shore i s almost barren of mineralization.. Due to the steep and d i f f i c u l t terrain of the area, many steam-Dperated aerial tramways were built to the mines. Over sixty of these were built in Slocan and Slocan City camps, the longest being the Silverton to Mammoth mine tram. The whole area has had a history of overinvestment. The ruins of many concentrating mills sprawl beside the creeks, mills that ran out of ore before the companies made their profits. Today, l i t t l e exploration or 8. development work i s being done i n Slocan City camp. Claims have been allowed to lapse (tinlike the Slocan camp properties) and comparatively few mines have operated during the past decade. RECENT ACTIVITY The future of the area as a viable mining camp has been judged poor by popular opinion. Most companies seem to feel that a l l possible vein lodes were traced out by prospectors back near the turn of the century, and the ore grubbed out by hand tools. Regional controls of the ore are not obvious, though individual mines display abundant and varied ore controls. The mass of published data on the camp, however, has never been brought together under one format for analysis - i t may well reveal the better targets for more specialized local examination by techniques that are new to the Slocan City camp, but well known otherwise. There has been a recent quickening of interest and activity i n the Slocan area generally. Several mines of the Slocan City camp are producing intermittantly, and various forms of development work are being done on others. A partial l i s t of mines operating i n the area at various times during the past three years includes: Freddy L i t t l e Tim Homestake Meteor Alice S Arlington Colorado Ottawa Enterprise Joyce Westmont and Eastmont Myrtle New access roads have been bulldozed to the Gold Viking, Hampton, Rocklands, Slocan Prince, Two Friends, Black Prince, and Bank of England properties. 9. The Speculator northeast of the Arlington deposit has a good access road, and the old mine dump has been channel sampled recently. Minor amounts of work have been done on other properties such as the Smeralda. Even the Senator (Bachelor) property now has a new ladder to the lower workings. Nearly a l l this work i s local; poorly financed and necessarily sporadic i n nature. A few men who know the area well estimate that for a minimum of $50,000 any of a choice of properties could be brought into production -with a possible tenfold yield. 10. CHAPTER TWO MINERALOGY OP SLOCAN CITY DEPOSITS GENERAL GEOLOGY Mineral deposits of the Slocan City mining camp are nearly a l l housed i n various phases of the Nelson batholith, dated recently at about 162 m.y.; lowermost Middle Jurassic (Nguyen, Sinclair, and Libby, 1968). Erosion following the emplacement of this plutonic rock has uncovered several phases of granitic rock, with random exposures of various para-gneisses. A strip paralleling the lake just north of Slocan City i s composed of an intensely deformed gneissic metasediment dipping eastward. It i s structurally overlain by a foliated leucogranitic augen gneiss which grades through a heavily chloritized and fractured vertical "crush" zone to Nelson granites (coarse grained hornblende-biotite granodiorite to quartz monzo-nite, with large euhedral phenocrysts of potassium feldspar). There are outcrops to the south of a similar, but non-porphyritic member; an equi-granular biotite-hornblende granodiorite. The batholith contains several masses of the slightly younger Vahalla plutonic rocks. A few metasedimentary roof pendants are scattered through the western margin of Slocan City camp. Most of these are a r g i l l i t e s or quartz-ites, with minor amounts of marble; a l l derived from the Upper Triassic Slocan Group ( L i t t l e , I960, p. 54). Several of the mines have dr i f t s cutting these rock types, while a few are completely contained i n them: such as two disseminations i n shear zones (L.H. and Rocklands properties), and one 11. unique skarn deposit (Piedmont, or Hope #2). CLASSIFICATION OF DEPOSITS Nearly a l l of the veins are sharply defined cross-cutting fissures, with relatively simple gangue and alteration mineral suites. Wallrock alteration includes s i l i c i f i c a t i o n , sericitization, chloritization, carbona-tization, pyritization, and feldspathization (K-spar with hematite), Gangue minerals were ever-abundant quartz, with minor amounts of calcite, siderite, barite, or fluorite. The ores i n general are quartz veins cutting plutonic rocks. The low total percentage of vein sulphides yields silver and gold, with minor lead and zinc values. A standard mineralogy i s pyrite, galena, sphalerite, tetrahedrite, argentite, native silver, chalcopyrite, and ruby silvers. TABLE II':. Average Percentages and Frequencies for Major Minerals of the Slocan City camp, B.C. MINERAL APPROXIMATE AVERAGE FREQUENCY Pyrite 3.7$ 59 Galena 2.9$ 58 Sphalerite 1.8$ 55 Tetrahedrite 0.9$ 35 Total Sulphides i n Vein 10.4$ (geometric mean) 70 Cairnes (l934> pp.112-116) defined types of deposits found i n the Slocan and Slocan City camps. His group four "dry" ores are the typical 12. ores of the Slocan Cityj silver ores with minor lead and zinc values, abundant quartz gangue, and a Nelson granitic host. The writer agrees with Cairnes' separate classification for the "dry" ores of the Slocan camp. Those quartz veins cutting plutonic rocks are distinguished by their suite of ore minerals: tetrahedrite (freibergite), pyrite, chalcopyrite, stibnite, silver, argentite, and ruby silvers. There i s only minor galena, and no sphalerite whatever. Cairnes set up his group two classification of gold values i n quartz, with a possible mineralogy of pyrite, pyrrhotite, chalcopyrite, arsenopyrite, and gold. No silver, lead, or zinc values were involved. Two of the three properites mentioned were the L.H. (with anomalous late native arsenic carrying s i l v e r values), and Rocklands properties of the northern Slocan City area - both atypical disseminations through heavily s i l i c i f i e d shear zones. The writer has records of three other gold-quartz deposits i n the immediate area that suggest a modification to Cairnes' category. The L i t t l e Daisy, Golden, and Get There, E l i deposits contain gold and silver values, i n quartz veins that cut Nelson plutonic rocks. The possible mineralogy includes pyrite, with gold, chalcopyrite, pyrrhotite, galena, and perhaps sphalerite. ANALYSIS OF SAMPLES Samples of ore from 3 7 mines i n the Slocan City camp were collected during the summer of 1 9 7 0 . The mineralogy of ore and gangue was estimated in the f i e l d , and notes on the nature of wallrock alteration recorded. Evidence of cyclic fracturing and deposition of vein materials i s not 13. uncommon; often one set of fractures grades much richer than the rest i n the larger vein lodes. Laboratory work began with established hand specimen analysis techniques. Large specimens yielded the most diverse and dependable infor-mation. Several of the minerals are worth mentioning for the unusual habit they displayed. Argentite occurred as soft black elongate crystals i n quartz. Native silver formed fresh lustrous flakes or less commonly wire silver. Fresh galena had an exceptionally bright lustre, which eventually tarnished through shades of iridescent blue to a dull grey. Sphalerite i s a resinous yellow brown i n most cases,but some specimens closely resembled a form of tetrahedrite with anomalous cleavage. Ruby silvers were a dull translucent reddish grey. Other minerals obvious i n hand specimen, such as pyrite, chalcopyrite, tetrahedrite, and the gangue minerals^ occurred normally. ORE MINERALOGY  Magnetite Magnetite i s extremely rare, occurring i n a few mines toward the southern end of the camp. This high temperature hypogene oxide probably formed early i n the paragenesis. It i s associated with pyrite i n the Chapleau mine. Magnetite i s replaced by hematite (supergene?) i n ores from the Alice S and V&M properties ( f i g . 18). 1 4 . Pyrite Pyrite i s widespread throughout the camp. I t i s most abundant i n a peripheral belt about a pyrite-poor central area. This zoning was tested by examining the geographic positions of the following categories: ( 1 ) Pyrite absent (2) Trace amounts of pyrite i n s o l i t a r y grains (3) Pyrite replaced to various degrees by p r i n c i p a l l y sphalerite and galena ( 4 ) Fresh euhedral cubes of p y r i t e . Results show a central barren area bounded on the south and west by a spotty belt of s o l i t a r y pyrite grains. Replaced pyrite blended sporadically with t h i s a l l around i t s perimeter. The large unreplaced pyrite crystals plotted farthest from the core area, toward the south and west. Quite possibly, then, the pyrite formed as a primary sulphide halo i n quartz veins, surrounding a pyrite-deficient zone. This belt was "overtaken" and replaced by l a t e r deposition of galena and sphalerite mineralization (most abundant i n the central core). None of the other minerals show a good positive correlation with p y r i t e ; though native s i l v e r , argentite, and tetrahedrite display a s l i g h t relationship to i t s map plot. Galena, sphalerite, chalcopyrite, and ruby s i l v e r s have a negative correlation with pyri t e . Pyrite was the f i r s t hypogene sulphide to form. Excellent cubes are found i n the Chapleau and Goldstream mines. Elsewhere, pyrite i s replaced i n the ores of one mine or another by almost every other sulphide mineral, Miles n 1 — — i 7~ r. n z i& c '6.0 'fl.o no FIGURE 3 Contoured Pyrite Distribution 16, particularly sphalerite and galena. Supergene goethite rims some pyrite. Arsenopyrite Arsenopyrite occurs in only one deposit, the anomalous L.H. mine. It is associated with pyrite and pyrrhotite. Apparently gold values are linked with arsenopyrite in this mine (Cairnes, 1934, p.125). Scheelite Two lumps of scheelite weighing a total of 525 pounds were identified in the vein material from the Meteor mine (Cairnes, 1934, p.128). Pyrrhotite Extremely rare, pyrrhotite probably formed after pyrite and simultaneously with sphalerite in the paragenetic sequence (fig. 23). Trace amounts occur in Chapleau ores. The Piedmont (Hope #2) mine has massive pyrrhotite associated with chalcopyrite and sphalerite, and pyrrhotite exsolved from sphalerite along with chalcopyrite; in a skarn of garnet, diopside, and calcite.^ Marcasite Well developed marcasite occurs in the Piedmont mine, where i t heavily replaces pyrrhotite along crystallographic planes. It is associated with pyrrhotite, sphalerite, and chalcopyrite (fig. 23). 17. B Pi) 0 W . O ~T " I .6 .0 ~1 ;R.O _ T — nu.o — i — n«?.t) 84 o FIGURE 4 Contoured S p h a l e r i t e D i s t r i b u t i o n 13. S p h a l e r i t e S p h a l e r i t e i s a r a t h e r common v e i n m i n e r a l , though i n small amounts. I t i s d i s t r i b u t e d as a c e n t r a l high, w i t h a narrow t r o u g h - l i k e low t r e n d i n g northwest through the southern h a l f of the camp. In the paragenetic sequence i t f o l l o w s , and r e p l a c e s , p y r i t e . A contoured p l o t of s p h a l e r i t e abundances ( f i g . 4) c o r r e l a t e s c l o s e l y w i t h that of galena ( f i g . 3 ) • T e t r a h e d r i t e and c h a l c o p y r i t e a l s o d i s p l a y a p o s i t i v e r e l a t i o n s h i p w i t h s p h a l e r i t e . P y r i t e c o r r e l a t e s n e g a t i v e -l y w i t h s p h a l e r i t e . S p h a l e r i t e commonly contains exsolved blebs of c h a l c o p y r i t e (fig.12) w i t h e i t h e r emulsion or c r y s t a l l o g r a p h i c t e x t u r e . T e t r a h e d r i t e ( L i t t l e Tim, Neepawa, and Bondholder), and p y r r h o t i t e (Piedmont) a l s o occur as p o s s i b l e e x s o l u t i o n blebs i n s p h a l e r i t e , but more r a r e l y . S p h a l e r i t e , found i n a s s o c i a t i o n w i t h galena and c h a l c o p y r i t e (Hampton), and w i t h t e t r a h e d r i t e as w e l l ; i s replaced by galena (Westmont), t e t r a h e d r i t e ( L i l y B), and c h a l c o p y r i t e (Meteor). In one case, the cleavage planes of the r e p l a c e d s p h a l e r i t e are v i s i b l e extending i n t o an adjacent g r a i n of c a l c i t e . C h a l c o p y r i t e C h a l c o p y r i t e i s present i n minor amounts i n many mines of the area. The only w e l l defined h i g h occurs around the Ottawa, Tamarack, and Anna mines, s l i g h t l y south of the p y r i t e - p o o r c e n t r a l zone. C h a l c o p y r i t e c o r r e -l a t e s w i t h t e t r a h e d r i t e , a r g e n t i t e , and n a t i v e s i l v e r . P y r i t e d i s p l a y s a Contoured Chalcooyrite D i s t r i b u t i o n 21. negative correlation with chalcopyrite. In the paragenetic sequence, chalcopyrite appears to be i n part contemporaneous with and i n part later than sphalerite ( f i g . 22). It re-places argentite (Meteor), and pyrite (Two Friends); and i s replaced by supergene goethite (Howard Fraction). Slocan Bob ores display excellent crystallographic textures of aligned chalcopyrite i n sphalerite (fig.12). Native Gold (Electrum) Native gold occurs rarely i n the Slocan City camp. The Neepawa, L.H., Chapleau, Republic, Arlington, Meteor, Coronation, and Golden properties have native gold or electrum as tiny grains i n quartz. There i s no particular spatial distribution of native gold i n the camp. Native gold i s associated with pyrite, chalcopyrite, rarely tetrahedrite (fig.16); and i n one case with arsenopyrite. Galena Galena i s widespread throughout the Slocan City camp,being present in minor amounts at most times. It i s most abundant in the central area and to the northwest, with low amounts occurring to the southwest and extreme north. It follows sphalerite and deposited contemporaneously with late chalcopyrite and much of the tetrahedrite. Galena i s closely related to sphalerite, and less positively to tetrahedrite. Pyrite correlates negatively with galena. Galena locally has replaced both pyrite and sphalerite, and i s AYLWIN P E A K x '0 Miles 3 6b.a i — c a . o n — /ci.o - i 1 1—" 12. 'J 71 C /6.0 V-HVrs i /H.O FIGURE 7 Contoured Tetrahedrite D i s t r i b u t i o n 2 3 . associated with or rimmed by chalcopyrite. Excellent intergrowths of galena and tetrahedrite occur in the L i l y B mine. Galena i s apparently barren of si l v e r i n solid solution, based on electron microprobe analysis of Arlington ores. It does contain blebs of argentite, ruby silvers, and occasionally native silve r (one subhedral crystal of native silver was found i n galena, Black Prince property). It has been replaced by calcite and perhaps tetra-hedrite i n other mines ( f i g . 19) . Tetrahedrite Tetrahedrite occurs far less commonly than expected, based on the mineralogy of the "dry" ores of the Slocan camp. The southern half of Slocan City camp i s rather barren, with minor highs plotting north and east. The Homestake mine has comparatively abundant tetrahedrite. It i s dis-tributed similarly to chalcopyrite, native silver, and sphalerite, Pyrite and ruby silvers correlate negatively with tetrahedrite. Tetrahedrite seems contemporaneous with chalcopyrite i n the para-genetic sequence ( f i g . 2 2 ) , but some of the evidence i s contradictory. Along with chalcopyrite, i t i s exsolved from sphalerite i n ores of Neepawa and L i t t l e Tim mines. Hampton ores contain complex intergrowths of tetra-hedrite and galena ( f i g . 11). Tetrahedrite replaces galena and i s associa-ted with electrum i n the Howard Fraction. Chalcopyrite replaces tetrahedrite i n Coronation ores. Host examples of this mineral should be called freibergite (low hardness and high silve r content). True tetrahedrite, and possibly tennantite do occur i n the camp as well. 25. Native Silver Much of the silve r value i s probably due to minor amounts of native silver, which form a central high slightly southwest of the peaks for galena and sphalerite abundances. The highest percentages occur i n Meteor and Anna ores. Most of the native silver i s probably hypogene. It i s associated with galena, pyrite, chalcopyrite, and tetrahedrite. Lobes of native silver interlock with argentite (Meteor ore, f i g . 10), and are replaced by argentite i n Tamarack ores. A subhedral crystal of native silver i s i n -cluded i n galena ( f i g . 2l), and other silver f i l l s a fracture i n quartz from Black Prince vein material. Native silve r possibly replaces galena (Alice S). The distribution of native silve r correlates positively with argentite, chalcopyrite, and tetrahedrite. Ruby Silvers The ruby silvers (mostly pyrargyrite) occur far less commonly and at lower percentages than would be considered appropriate from the high silver values i n the camp. Ruby silvers are spread sporadically across the camp, with perhaps a slight eastern high. They occur late i n the para-genesis, during and after the last stages of galena deposition. Ruby silvers form lath-like crystals i n quartz ( f i g . 20) of Goldstream and Chapleau ores. They form blebs i n galena (Alice S), and replace pyrite, sphalerite, and galena (Alice S, Black Prince, and Joyce FIGURE 9 Contoured Argentite D i s t r i b u t i o n 27. properties). Host of the ruby silvers examined seemed hypogene, except for some extremely fine grained aggregates in vuggy calcite which might possibly be supergene. Stephanite This silver sulphosalt, 5Ag2S«Sb2S^, has a slightly greater hard-ness than the ruby silvers pyrargyrite and proustite. It has no internal reflection, and displays a strong anisotropism. It has been positively identified i n ores of the Anna, Arlington, and Tamarack mines. Argentite Trace amounts of argentite are found throughout the camp, with a barren zone toward the southwest. Argentite forms late, occurring i n both hypogene and supergene sulphide categories. It i s replaced by chalcopyrite (Meteor and Tamarack mines, f i g . 15), and by late calcite (Black Prince). Argentite i s later than ruby silvers of the Goldstream mine (which i t has replaced) (fig.20). Argentite replaces galena in ores from Slocan Prince and Alice S. and possibly replaces native silver (Black Prince). Argentite replaces goethite, which in turn i s a supergene replace-ment of chalcopyrite (Howard Fraction property); indicating that some argentite i s definitely supergene. 2 8 . Native Arsenic Native arsenic occurs with c a l c i t e stringers cross-cutting an orebody i n the L.H. mine. S i l v e r values were associated with these late stage minerals (Cairnes, 1934, p. 112). Molybdenite A sample containing a single rosette of molybdenite was collected from a cross-cutting pegmatite dyke near the Ottawa mine above Springer creek. Cairnes (1934, p. 127) recorded molybdenite from lower Enterprise creek, associated with high temperature quartz veining a pegmatitic granite. SUPERGBNE MINERALOGY Goethite Goethite forms perfect rims on pyrite cubes i n the southern ha l f of the camp, replaces chalcopyrite (Howard Fraction), and i s produced by weathering of s i d e r i t e . Hematite Hematite i s probably supergene, replacing magnetite i n ores from V&M ( f i g . 18) .and A l i c e S mines. 29. Anglesite Anglesite f i l l s thin fractures i n galena from the upper oxida-tion zone of several mines i n Slocan City camp. Azurite and Malachite These two copper carbonates replace chalcopyrite and tetra-hedrite, especially i n the oxidized zone of the shear at Rocklands mine. Chalcocite There i s a trace of chalcocite, probably after chalcopyrite; at the Lakeview property on Springer creek just above Slocan City. Cerrusite Cerrusite occurs as a soft flakey weathering product i n the outcrops of veins containing abundant galena. GAHGUE MIIIERALOGY Quartz Quartz i s recorded as the gangue for some 68 mines. It f i l l s on the average perhaps QOfo of every vein in the camp. Early quartz i s some-times associated with chlorite (Joyce mine). Later varieties include 30. both massive white quartz, and open space f i l l i n g s by moderately clear crystals interlocked i n vugs or grown perpendicular to the walls of frac-tures cutting the ore. Some late banded chalcedony was noticed at the Kalispell mine. Quartz is associated with a l l other minerals found i n the camp. Calcite Coarsely crystalline calcite probably f i r s t precipitated contemporaneously with late galena and some of the silve r minerals, Later calcite commonly forms layered masses and f i l l s vugs with clear crystals. Calcite i s distributed throughout the camp i n the gangue of at least 32 mines. Siderite There are only 14 mines with recorded siderite gangue, and they a l l occur i n a zone slightly northeast of the pyrite-poor core. This correlates positively with sphalerite, galena, and chalcopyrite. Siderite probably occurs earlier i n the paragenetic sequence than calcite. Siderite i s possibly replaced by late galena. It weathers to a dark reddish brown caused by a mixture of manganese and iron oxides. Barite The nine mines with barite gangue are spread over a narrow north-31. south zone just west of the core area. Barite has not been recorded i n mines that also have siderite. There i s a good positive correlation between barite and such minerals as native silver and argentite. Barite probably occurs simultaneously with calcite i n the paragenesis. .. Fluorite Fluorite i s uncommon i n the camp, occurring i n perhaps three mines. It i s definitely late i n the paragenetic sequence. Figure 10. Argentite (grey-green) and native silv e r (white), replaced by chalcopyrite (yellow): Meteor mine. Figure 11. Sphalerite (dark grey) with chalcopyrite (yellow blebs), surrounded by an intergrowth of galena (white) and freibergite (pale green-grey): Hampton mine. Figure 12. Massive sphalerite (dark grey-green), exsolving some tetrahedrite (pale green-grey) with crystallographically orientated blebs of chalcopyrite (yellow); pyrite (yellowish white) i s present: Slocan Bob mine. Figure 13. Tetrahedrite (brown-grey), galena (white), and chalcopyrite (yellow); sphalerite (pale grey) i s present: Enterprise mine. 34. Figure 14. Sphalerite (grey) and chalcopyrite (yellow) near electrum? (bright white); argentite (pale grey) against electrum and after chalcopyrite: Ottawa mine. Figure 15. Massive argentite (brown-grey) rimmed by chalcopyrite (yellow): Tamarack mine. Figure 16. Sphalerite (medium grey) with chalcopyrite (yellow) and tetrahedrite (white); electrum (bright yellowish white) in tetrahedrite: Coronation mine. Figure 17. Freibergite (green-grey) in galena (grey with triangular p i t s ) : Kalispell mine. 36. Mag j * *" - TP] -Figure 18. Magnetite (pale grey) replaced by hematite (brown): V&M mine. Figure 19. Galena (white, with triangular pits) sur-rounded by a matching halo of galena blebs i n calcite gangue; possibly cyclic deposition: Enterprise mine. 37. Figure 20. Laths of ruby silve r (pale grey) surrounded and replaced by argentite (dull greenish grey) in quartz gangue: Goldstream mine. Figure 21. Native silver (pale cream) crystal i n massive galena (green-grey): Black Prince mine. Figure 22. Tetrahedrite (dull green-grey), chalcopyrite (yellow) and sphalerite (dark brown-grey); surrounded by massive galena (pale grey): L i t t l e Tim mine. Figure 23. Pyrrhotite (olive brown) replaced along fractures by marcasite (pale yellow-grey) with prominent cleavage: Hope #2 mine. 39. VERTICAL ZONING HYPOTHESIS A concept of vertical zoning i n the Slocan camp to the north has been under examination since i t was f i r s t proposed by Cairnes (1934). He observed a change i n mineralogy ve r t i c a l l y down many vein lodes. Outcrops had silve r minerals and galena i n a carbonate gangue. Regular sampling at increasing depth found a gradual change to a pyrite and sphalerite i n quartz ore. Cairnes accounted for this with, a steep thermal gradient con-t r o l l i n g deposition; operating i n relation to a surface very similar to the present topography, despite the passage of 160 million years and the removal by erosion of probably a f u l l mile of rock. Hedley (l952), observing the same f i e l d evidence, considered i t a pressure phenomena; as the veins dilated closer to the surface, the lowered confining pressure led to a change i n the mineralogy. In the Slocan City camp the r e l i e f i s less and the environment of deposition far different; but the possibility of vertical zoning in the ore minerals does exist. In order to test such a hypothesis, one could conduct a complete vertical sampling of several major vein lodes to ascertain how and i f the values change. Failing this, however, and supplied with a data f i l e containing outcrop elevations, average metal assays, and the typical mineralogy i n each vein, the writer examined a slightly different concept; of overall vertical zoning. The best way to attempt this would be with a three dimensional trend program, to give an accurate slice-by-slice view of any zoning or patterns both vertical and horizontal. Since no such program was available, 40. INDEPENDENT VARIABLE FREQUENCY CORRELATION (R) $ VARIANCE EXPL (R 2xl00) Silver 70 0.0036 0.00$ Lead 47 0.0262 0.07$ Zinc 34 -0.2021 4.09$ Gold 45 0.0412 0.17$ Galena 58 0.1036 1,07$ Sphalerite 55 -0.0160 0.03$ Pyrite 59 -0.1283 1.65$ Tetrahedrite 35 -0.0034 0.00$ - A l l linear correlations are not significant. - The dependent variable i n each case i s elevation. Table III. Linear Correlations, Frequencies, and $ Variance Accounted for by Regression Analysis of Metal Grades and Mineralogy, against Elevation. 41. the w r i t e r adapted a l e s s s o p h i s t i c a t e d approach i n v o l v i n g p l o t s of e l e v a -t i o n versus a v a r i e t y of other v a r i a b l e s . L i n e a r c o r r e l a t i o n c o e f f i c i e n t s were obtained at the same time f o r e l e v a t i o n versus other v a r i a b l e s as l i s t e d i n Table I I I , None of these f i g u r e s were s i g n i f i c a n t to the f i v e percent l e v e l ; they could be the product of random sampling e q u a l l y w e l l as the r e s u l t of v e r t i c a l zoning. The r e s u l t s have not proved that v e r t i c a l zoning i s non-existent i n the area. They i n d i c a t e , however, that i f v e r t i c a l zoning does e x i s t , i t i s e i t h e r not present as a simple f u n c t i o n of e l e v a t i o n , or e l s e the v e r t i -c a l r e l i e f e x i s t i n g i n the camp i s i n s u f f i c i e n t to show such zoning. CONCLUSIONS The v e i n s of the Slocan C i t y camp are remarkably s i m i l a r i n many re s p e c t s . They n e a r l y a l l occur as f i s s u r e s or v e i n lodes c u t t i n g p l u t o n i c rock. The v e i n s are predominantly quartz, w i t h p y r i t e , galena, s p h a l e r i t e , t e t r a h e d r i t e , s i l v e r m i n e r a l s , and minor carbonates. Metal values recovered from ores of the area i n c l u d e s i l v e r , gold, l e a d , z i n c , cadmium, and copper; i n order of decreasing economic importance; S i l v e r apparently d e r i v e s mainly from n a t i v e s i l v e r , a r g e n t i t e , and f r e i b e r g i t e , while ruby s i l v e r s account f o r very l i t t l e . The gold seems n e a r l y absent from the mineralogy. Some t i n y f l a k e s of f r e e gold do occur i n a v e ry few mines, but these values probably would not be recovered by the smelter. Lead and z i n c come from the more abundant galena and s p h a l e r i t e r e s p e c t i v e l y ; but as the average percentage of sulphides i s low, 42. FIGURE 24 Van der Veen Diagram of Paramnesia FIGURE 25 Bar Graph Diagram of Paragenesis for Slocan City Ores GANGUE MINERALS Quartz Calcite Siderite Barite Fluorite I I Jarnet/Calcite /Pyroxene HYPOGENE MINERALS Scheelite Pyrite Magnetite Arsenopyrite Pyrrhotite Marcasite Sphalerite Chalcopyrite Gold Tetrahedrite Silver Galena Ruby Silvers Stephanite Argentite Freibergite Arsenic WEATHERING AND SUPERGENE MINERALS Goethite - after pyrite, chalcopyrite, and siderite Hematite - after magnetite Anglesite - f i l l s fine cracks in galena Azurite - after chalcopyrite and tetrahedrite Malachite - after chalcopyrite and tetrahedrite Chalcocite - after chalcopyrite, very rare Cerussite - after galena in oxidized outcrops 43. these values remain minor. Both reported cadmium returns were probably principally derived from sphalerite. Warren and Thompson (l945) detected the cadmium content of sphalerites. The only copper return recorded came from a chalcopyrite rich shipment of ore from the Anna mine in 1918. There i s a definite pattern to the mineralogy as a whole that resembles a concentric form of zoning. An abundant peripheral halo of fresh pyrite becomes sporadic and increasingly replaced towards a central core, which i s barren of any sign of pyrite. This same core i s high i n galena and sphalerite. Siderite or barite gangue i s much commoner i n this central zone. Tetrahedrite, chalcopyrite, and most of the silver minerals are distributed irregularly across the camp, with a slight tendency toward central highs. The possibility that pyrite existed at one time i n the nov; pyrite-poor central zone must be considered. Both galena and sphalerite have replaced pyrite extensively. In the central zone where these two minerals are most abundant, any early formed pyrite could have been completely re-placed. However, as only isolated - not r e l i c t - grains of pyrite have been found i n deposits from the core, i t appears l i k e l y that i f pyrite did exist there early i n the depositional history, i t was present in only very small amounts relative to elsewhere i n the camp. The lateral zonal distribution of minerals i s somewhat unusual i n comparison to Emmons' zonal vein sequence (1940, p.196) derived from batholiths. The pyrite fringe with minor precious metal values might correspond to his barren level five; while the galena, sphalerite, and silver core zone could be a sparse combined version of levels six (silver) FIGURE 26 Diagrammatic Cross-Section of Inferred Mineral Zonation Pattern (On a line drawn from just north of Slocan City to the Speculator Mine: see Figure 2 ) SCALE VERTICAL I = 5000 HORIZONTAL I = 4224 / ° o l 0 o / ° 0 /oo|° / o ° o v O I o / O o r 0 ° l o ' 0 o ° .roo°|/o 0o°o° ^ o 0 / o 0 o ° ° 0 oo o ° ° o ° ° o ° o o Speculator(47) LEGEND + Geology after Ross and Keflerhals, 1968 GEOLOGY - NELSON Plutonic - Granite Gneiss - Crush Zone - Horsethief Creek Gp MINERALOGY - P y r i t e > 5 % - Pyrite 1-5 % - Galena > I 0 % - Galena 5-10% %o?e - Sphalerite > I 0 % Spholerite 5 - 1 0 % e • • Chalcopyrite > 5 % 45. and seven (lead). The paragenetic sequence of ore-forming minerals appears standard; magnetite, p y r i t e , arsenopyrite, p y r r h o t i t e , marcasite, s p h a l e r i t e , chalco-p y r i t e , gold, t e t r a h e d r i t e , galena, s i l v e r , stephanite, ruby s i l v e r s , and arg e n t i t e . High temperature molybdenite was deposited w e l l a f t e r the hypo-gene ores had been formed. The paragenetic sequence i s much harder to decipher f o r the gangue. In probable order of i n i t i a l appearance, the minerals were quartz, s i d e r i t e , c a l c i t e , b a r i t e , and f l u o r i t e ; with repeated subsequent periods of p r e c i p i -t a t i o n f o r quartz and carbonates. The Slocan C i t y deposits are probably the r e s u l t of two separate pulses of ore-forming f l u i d s ; emanating from the same c e n t r a l source, and i n some way associated with the Nelson b a t h o l i t h . 46. CHAPTER THREE DEVELOPMENT OP A COMPUTER-PROCESSIBLE DATA PILE FOR SLOCAN CITY MINERAL DEPOSITS* INTRODUCTION Computerized data f i l e s are becoming increasingly important to mineral exploration companies in dealing with ever-increasing quantities of information, and as a basis for testing new methods of estimating exploration p r i o r i t i e s . In the past few years considerable time and money have been expended in an effort to produce f i l e s of geological and other data, with a variety of purposes i n mind. For example, several groups of researchers have been involved i n setting up computer f i l e s of information obtained i n the normal course of geological mapping (Wynne-Edwards et.al., 1970; Hutchison and Roddick, 1968). A larger comprehensive study i s that of the ad hoc committee on storage and retrieval of geological data i n Canada (Ediger and Brisbin, 1967). In a more specific way, industry has attempted to develop specialized f i l e s relating to mineral deposits (e.g. Drummond, 1969). Sutterlin and de Planke (1969) of the University of Western Ontario have developed a storage and retrieval system for mineral deposits which i s being applied i n i t i a l l y to the Cobalt camp in northern Ontario. There are many problems inherent i n the establishment of a data f i l e , i f the f i l e i s to be both comprehensive and useful for s c i e n t i f i c Itewn from: Orr and Sinclair, 1971. 47. and applied purposes. These include: 1) the high cost of establishing a comprehensive data f i l e ; 2) the highly variable quality of data available for different deposits and from different areas; 3) programming d i f f i c u l t i e s ; 4) the excessive time required to set up a f i l e and to code i n -formation; 5) the vaguaries of geological and other terms. The writer decided to investigate the possibility of preparing a computer-processible f i l e for a single mining camp as a means of determining the use of such a data base for (l) general evaluation of the mining camp in terms of establishing theories of ore control and ore genesis, and (2) i t s potential for outlining high priority explo-ration targets using a variety of multivariate s t a t i s t i c a l procedures. A third purpose i s the application of a data f i l e to the normal eva-luation approach in delineating exploration targets. The region chosen for this case history approach was the Slocan City mining camp. The homogeneity of the host Nelson plutonic rocks, and the great similarity of the ores led the writer to presuppose a single continuous network of open fractures and joints. Deposition of ore and gangue minerals i n such a system from a simple sequence of ore forming fluids would presumably be governed principally by temperature and pressure. Selection of this area was supported by the writer's familiarity with the region, and the abundance of published informa-tion available. 48. Only information that i s f a i r l y readily available has been recorded to f a c i l i t a t e investigation of the practical usefulness of the data f i l e . Many of the problems encountered i n setting up a comprehensive data f i l e for general application have been avoided, and time has been kept to a minimum, by confining the study to var i -ables that pertain to a particular area. This has the advantage of decreasing confusion i n dealing with coding forms. Programming d i f f i c u l t i e s are minimal because of the simple and r i g i d format, and the relatively small number of variables. Field examination by a single geologist has, hopefully, produced a uniformity i n the data. Despite the specific design to a particular project one should not forget that a relatively simple computer program could be written to translate the f i l e to a more general format. The study was envisaged as incorporating three stages: (l) accumulation of data from the literature and from various un-published, but publically available, sources; (2) f i e l d examination of as many deposits as possible, and laboratory investigation of their ores i n an effort to provide uniformity of quality and completeness for geological data; and (3) applications of the computer-processible f i l e . In a sense, of course, the data f i l e w i l l never be complete i n that new information i s continually becoming available. Many of the advantages of the f i l e have become apparent, however, particularly the ease and rapidity of data retrieval. 49. SLOCAN CITY DATA FILE The data f i l e could be considered a natural result of the matrix of facts relating to i t s development. The Slocan City camp has been worked for 78 years; with prospectors, companies, syndicates, and cartels spurring the search for ore. Today, the valley i s an economic disaster area. Tourists and lumber pay the piper. The camp seems worked out: but i n the working, a mass of data has accumulated about the general geology and each mine that is of great practical potential. A data f i l e was set up to house this store of information, and to easily accomodate new data arising from f i e l d work. It seemed appropriate to design a two card system for recording data from each deposit, the f i r s t card to contain a l l material to be found in the many published references and governmental f i l e s ; the second card to store f i e l d information and the results of laboratory research. The f i r s t card used annual reports of the British Columbia Depart-ment of Mines and Petroleum Resources as i t s principal source of informa-tion. Each yearly report from 1883 to 1968 was read thoroughly, and data on any of the mines in the Ainsworth, Slocan, and Slocan City camps was collected on separate sheets. Production summaries and special papers added very detailed information. The Geological Survey of Canada special volume on lead and zinc (Alcock, 1930, pp.340-347) proved useful, as did the various memoirs and preliminary reports concerning the area. Many different problems were encountered, however; most due to the wide variety of authors and departments that had recorded the original facts. One major hindrance was repetition of names: borders of the mining camp have been shifted over 50. the years, and mines of Lardeau, Crawford Bay, and more southerly d i s t r i c t s were lumped i n with Slocan mines of the same name. Mine mergers, and the mining of one property through another's workings added to the confusion. The ore i s very sporadic i n grade and appearance, and this irregularity made any channel or grab sample assays vi r t u a l l y useless. Some shipment assays were list e d as percentages, others as pounds of metal produced; and the units involved ranged through pounds, tons, sacks, and railway cars of ore. In addition, no record was kept of zinc values before roughly 1905, due to a smelter penalty on zinc. The f i r s t cadmium returns from the ores came in approximately 1953. In such cases, the most recent or most depend-able assays were used to extrapolate "hidden" grades for early shipments. Very l i t t l e factual information on the location of these mines was ever given; i t would be "two miles up the McAllister mine road"; a road that might have been both shortened and overgrown in part, or completely abandoned! The best source for locations was Geological Survey of Canada Memoir 177 (Cairnes, 1934). Cairnes' 1932 map showed a l l mines in existence at the time, even prospects that never produced any ore. Much assistance was obtained from various employees of the British Columbia Department of Mines and Petroleum Resources at their offices i n Vancouver, Nelson and Kaslo. Their records of taxes paid, and master maps showing the claims and claim numbers, aided immensely in pinpointing a number of smaller properties. Much information concerning both production and property location came from conversations with experienced miners and mine managers of the d i s t r i c t . Mr. P. M i l s (former manager of the Galena Farm), Mr. S. Pedley (former manager of the Victor), Mr. Van Hansen (operating the Freddy), Mr. Thickett (formerly i n the Ottawa, now working the Homestake and Joyce mines), and Mr. A. Kessler (miner and prospector l i v i n g i n Silverton) gave invaluable help. They indicated two specific problems as well,concerning typical behavior in the area. Often production records depend upon the mine owner's tax forms; ignored or neglected by many of the old miners. Since the d i s t r i c t i s ideal for small operations, many people hold claims or leases which they work occasionally, stockpiling the sacked ore i n their backyards u n t i l a new smelter schedule allows higher ieturns for silver and lead. The f i n a l data format used on the cards was the product of lengthy consideration, governed by the specific problems arising from each variable (Table IV). A location number was determined by plotting a l l the deposits (numbered by their alphabetical order) on a large-scale map, and assigning new numbers reading across and down from the northwest. The location (essential for any data manipulation beyond numerical analysis) was set as a six figure number, representing the easting and northing by the Universal Transverse Mercator grid overlay, common to most 1:50,000 topographic maps issued by the Department of Mines and Technical Surveys. Since many deposits span a wide elevation range, the A.M.S.L. height of either the principal exposure or the main workings was recorded. A l l years i n which ore was actually mined were totalled, and the f i n a l year of production was li s t e d by i t s last two digits. Tonnage recorded was the sum of annual production figures from the many different sources. Where conflicting figures appeared, the higher figure was chosen. There i s a bu i l t - i n bias COLUMNS DESCRIPTION 1-4 Location number, keyed to Camp and Map Position 5-13 Alphanumeric name 14-19 X and Y coordinates, UTM System 20-23 Elevation of main workings above sea level 24-25 Total years of production 26-32 Total recorded production, i n tons 33 Replacement 34 Conformable Fissure 35 Cross-cutting Fissure 2 - Minor 36 Massive Lode 3 - Present 37 Quartzite "*> 38 A r g i l l i t e 39 Limestone V. Host Rock ' Coded by 1 - Major 40 Nelson Granite 2 - Minor 41 Porph. Nelson Granite 3 - Present 42 Kaslo Greenstones A 43 Lamprophyre and basalt dykes 44 Aplite dykes 45 Quartz Proph/pegmatite dykes 45-51 Fissure Orientation 52-55 Silver Oz/ton 56-59 Lead, fo 60-63 Zinc, fo 64-68 Gold, oz/ton 69-72 Cadmium, #/ton 73-76 Copper, #/ton 77-78 Year of latest production 79 Classification of deposit as wet,dry anomalous, or float -after Cairnes 80 Unassigned Table IV. Coding System Slocan Data F i l e , Card #1. V Type of Deposit Coded by 1 - Major 53. f o r small deposits, most of which were subjected to hand picking; with the r e s u l t that t o t a l production i s r e l a t i v e l y low, and grade fi g u r e s are r e l a t i v e l y high. Grades f o r each metal were recorded as follows: oz/ton f o r s i l v e r and gold, percentages f o r lead and zinc, and lbs/ton f o r cadmium, antimony, and copper. The average grade and t o t a l production of ore can be used to c a l c u l a t e the t o t a l d o l l a r value i n terms of present day metal p r i c e s . Consequently, d o l l a r value was excluded from the f i l e . The deposit type, host rock, and dyke rocks presented d i f f i c u l t i e s i n that the f i l e covered deposits whose wall rocks included Nelson granites, Slocan Group a r g i l l i t e s and quartzites, M i l f o r d Group sediments, and Kaslo greenstones to the east. Since the format was by no means intended to be u n i v e r s a l , t h i s information was condensed to a minimum of s i x i n d i v i d u a l catagories instead of using a prepared a l p h a b e t i c a l code f o r rock types. This data and the o r i e n t a t i o n of the main f i s s u r e were compiled from references or from the b r i e f f i e l d examination a l l o t t e d each property. The second card f o r each deposit (Table V) was intended to accommodate the f i e l d data, and the r e s u l t s of laboratory research. Local wall rock a l t e r a t i o n was measured su b j e c t i v e l y , based on the r e l a t i v e abundances of any of the following s i x minerals: quartz, s e r i c i t e , chlo-r i t e , carbonate, potassium feldspar (with hematite), and p y r i t e . Relative i n t e n s i t i e s v/ere recorded on an a r b i t r a r y scale: 1) fresh, unaltered host rock; 2) minor fractures or j o i n t s are l i n e d with t h i n layers of a l t e r a -t i o n minerals; 3) extensive f r a c t u r i n g with v e i n l e t s of quartz or carbonate, perhaps COLUMNS DESCRIPTION 1-4 5-10 11 12-17 18-20 21-22 23-24 25-26 29-30 31-32 33-34 35-36 37-38 39-40 41-42 43-44 45-46 47-48 49-50 51-52 53 54 55 56 57-80 Location Number Orientation of prominent cleavage in wall rock Intensity of alteration (range 1-5) Alteration minerals, Silica, Sericite, Chlorite, Carbonate, K-spar (Hematite), Pyrite Volume Percent Sulphides in Vein Quartz Pluorite Barite Dolomite Siderite. Galena Sphalerite Pyrite Tetrahedrite Pyrrhotite Chalcopyrite Polybasite Argentite Native Silver Stibnite . Gangue Minerals (Abundance and Paragenesis) y Principal Ore Minerals (Coded Percentage and Paragenesis) Arsenopyrite Gold Magnetite Goethite Unassigned Table V. Coding System Slocan Data Pile, Card #2, 55. t i n y p y r i t e c r y s t a l s or blebs of new s i l i c a developing i n the w a l l rock; 4) a spreading and blending of m i n e r a l f i l l e d f r a c t u r e s i n t o the w a l l rock, s i l i c i f i c a t i o n , c h l o r i t i z a t i o n , and p y r i t i z a t i o n proceeding throughout; 5) completely a l t e r e d , o r i g i n a l rock u n i d e n t i f i a b l e ; spotty, g r a n u l a r appearance. A l t e r a t i o n minerals present i n any one deposit were assigned i n t e g e r values i n ascending order of importance. Ore and gangue mineralogy was compiled from i n f o r m a t i o n i n the l i t e r a t u r e (Cairnes, 1935; F y l e s , 1967; S c h o f i e l d , 1920; L i t t l e , I960), and f i e l d and l a b o r a t o r y examination of hand specimens. T o t a l sulphide content was estimated from v e i n outcrops and under-ground exposures; or, f a i l i n g t h a t , from grab samples of dump m a t e r i a l . Gangue minerals are l i s t e d i n order of abundance. The sulphide mass, how-ever, i s s p l i t i n t o i t s component minerals and coded by a range of percent-ages: 1) l e s s than a tenth of a percent (trace amounts) of the sulphide present; 2) a t e n t h to one percent; 3) two to f i v e percent; 4) s i x to ten percent; 5) eleven to f i f t e e n percent; 6) g r e a t e r than f i f t e e n percent. Each mine's paragenetic sequence i n c l u d i n g both gangue and p r i n c i p a l 56. sulphides (based on the i n i t i a l appearance of each mineral) has been established from a mineralographic examination of the collected ores. Every mineral has either an individual paragenetic number, or shares i t with a contemporaneous mineral. One of the major advantages of computer-processible data f i l e s i s that the information i s stored in such a manner that i t can be manipulated and extracted rapidly at low cost. Unforeseen applications and new concepts can be examined ef f i c i e n t l y (using standard, readily available computer programs) without laborious repeated scanning of notes gathered during months of f i e l d work. 57. CHAPTER FOUR ANALYSIS OF SINGLE VARIABLES INTRODUCTION A useful early procedure i n the analysis of a mass of numerical data i s i t s presentation as common bar histograms. A histogram assists i n deciding upon suitable contour intervals for subsequent plot maps, and aids in choosing cutoff grades for anomalous highs, ore, and waste rock. Basic-ally , however, histogram analysis i s useful as a preliminary estimate, a general appreciation of the nature of each variable and i t s frequency dis-tribution (Lepeltier, 1969). It should be remembered that the variables carry no identification or location index through a histogram analysis. A large number of classical s t a t i s t i c a l tests are made with the understanding that the data has a normal or Gaussian distribution. If this i s not so, the data must be transformed using some appropriate function; logarithm, arc sine, log log, square, etc., each of which maintains the same relative order among values i n any given population. As i t happens, many variables i n nature display a positively skewed leptokurtic d i s t r i -bution (Shaw, 1961; Ahrens, 1954), and are best normalized by a log transform. Cumulative percentage curves drawn on probability paper constitute another method of simple graphical analysis. The typical unimodal log normal data distribution plots as a sigmoidal or "s" curve i n a standard cumulative graph. The same distribution forms a straight line on log N-£ f f r Y u l d t l v e --P¥o\fat 3 5 Oft 0rtQpl it 40 C 1 HE H E Average r o o T s i-t-Slocarv - r t 4 if ±4 i t U4J r—i-m 0.01 0.05 0.1 0.2 0.5 1 10 20 30 40 50 60 70 80 90 95 98 99 99.5 99.8 99.9 99.99 CO 59. probability paper (McCrossan, 1969). Surprisingly accurate estimates of the median (usually equivalent to a geometric mean) and standard deviation can be derived quickly. The most practical value of cumulative percentage probability plots, however, i s displayed i n application to bimodal data distributions. The graphs show straight line segments representing background and anoma-lous populations respectively; joined by a curved line derived from the mixed values ( f i g . 27). In contrast, the histogram of such distributions plot i n a one shouldered high that closely resembles a positively skewed curve. SLOCAN CITY UNIVARIANT DATA Visual examination of the histograms of each individual variable was desired to determine the type of distribution. Because of the large mass of data available for study, a computer program was written to pro-vide computer-plotted histograms for both arithmetic and logged values of a l l variables. In addition, means and standard deviations of the data were calculated. A l l bar intervals were set at one-quarter standard deviation. Continuous variables i n the Slocan City data f i l e were run through this program, and the resultant histograms are shown in figs. 28 - 33. The tonnages, percentage volume of vein sulphides, and each metal's assay grades from the Slocan City data a l l showed a lognormal distribution. Arithmetic values of elevation of workings, however, have a normal d i s t r i -bution. The numerical results (calculated means and standard deviations) are l i s t e d i n Table VI; including arithmetic values, and the antilogs for CD WX !2 — ti n it ^ = -Nl -10 OJ U) • S«—^- ; — ^ ; • '«.•;* fe*1:1' O -NI OJ "T" Ol _ i _ Ol o cn O O X I 2 n O ro — -vl O>OJ *-FIGURE 29 Histograms of Arithmetic and Logarithmic Values f o r S i l v e r 62. FIGURE 30 Histograms of Arithmetic and Logarithmic Values f o r Lead 63. N * 34 X = 3 76 S * 5 09 BI = I 27 •100 75 A N 34 0 025 BP • 024 h50H N N tooj — - -o O O O O O O O - -I I I I ' I I I FIGURE 31 Histograms of Arithmetic and Logarithmic Values f o r Zinc 64 N = 45 X = 0-63 S = 0 87 B I 0 22 rlOO-r-75 N 45 071 BI = 0 24 r-50-^ FIGURE 32 Histograms of Arithmetic and Logarithmic Values f o r Gold 65. FIGURE 33 Histograms of Arithmetic and Logarithmic Values f o r Volume fo Sulphides 66. the geometric mean and range values. An individual variable - silver - has been analyzed as an i l l u s t r a -tion of the meaning behind these measures of central tendency. Arithmetic and geometric means were calculated, as well as the median value from a plot of the cumulative percentages against the log values, on probability graph paper. These parameter estimates were: arithmetic, 88.9 oz.Ag/ton; geometric, 39.0 oz.Ag/ton; and median, 56.9 oz.Ag/ton. The positively skewed arithmetic distribution has a dubious mean strongly influenced by a few extremely high grades. The geometric mean from what closely resembles a normal distribution, i s probably the most dependable for s t a t i s t i c a l purposes. The cumulative percentage median, however, does not equal the geometric mean; as i t should i f the silver values were unimodal. This dis-crepancy between geometric mean and graphic median i s a strong indication of a bimodal distribution. The cumulative curve was plotted with grouped instead of raw data, but figure 27 gives reasonable support for the existence of a second anomalous population i n the silver grades. The average gross dollar value per ton for the ores of Slocan City camp i s 8 82.04 using 1971 values (Engineering and Mining Journal, February 1971) and the geometric means for each variable of metal assay grades. The arithmetic means gave a value of $200.05. In contrast to this, Cairnes (l934, p. 77) gave an average gross dollar value of $38/ton for the Slocan City ores. In summary, the Slocan City camp could be des-cribed as low tonnage, predominantly quartz veins; grades of lead and zinc are very low, whereas the rich gold and silver minerals contribute moderately high precious metal grades to the average dollar value. Slocan City Variable Arithmetic Logarithmic N X S X X + S X - S Elevation (feet above mean sea level 73 5154.8 1310.6 4966.0* 6592.0 3742.0 Tonnage 73 1192.1 4109.3 44.1 508.2 3.8 Silver (Oz.Ag/ton) 70 88.9 97.7 39.0 208.5 7.3 Lead(WeLght Percentage) 47 5.98 7.96 2.13 15.21 0.30 Zinc(Weight Percentage) 34 3.76 5.09 1.06 9.66 0.12 Gold (Oz/ton) 45 0.63 0.87 0.19 1.79 0.02 Cadmium (Lbs/ton) 2 1.11 1.21 0.71 3.01 0.16 Percentage Sulphides by Volume 70 13.69 10.51 10.40 22.34 4.84 Each Logarithmic value l i s t e d i s the antilog of the calculated result. Table VI. Means and Standard Deviations for Selected Slocan City Variables. 63. A f i r s t hasty conclusion would restri c t the camp to one and two man mining operations; but the average grades and tonnage are controlled by the many minute showings, and de-emphasize the extreme highs. The dollar value of metals extracted from such deposits as the Enterprise (S3,308,502), the Arlington ($1,752,218) and the Ottawa ($2,726,198) should be kept i n mind. 69. CHAPTER FIVE . COMPUTER PLOTS INTRODUCTION Computer plots of data to scale represent one of the simplest applications of a computer to data analysis. In this study several types of basic plots were used to various ends, and serve to i l l u s t r a t e the advantage of having data readily available i n computer-processible form. Plots of tonnage, mine identification, mineralogy codes, strikes and dips of veins, and metal grades were obtained; a l l of which proved relevant to a general appreciation of the camp as a whole. As an example, figure 2 shows location of 73 deposits i n Slocan City camp that have produced one or more tons of ore. Table I l i s t s names and tonnages. These deposits form the basis of this study. VEIN ORIENTATION PLOT A concept of controlling main vein orientation has been proposed, at least for the Slocan camp to the north: "the fault fissures tend, on the whole, to stand at high angles,a condition which, particularly in the Slocan series, i s attributed to their control by a northeasterly system of steep joints" (Cairnes, 1934, p.80). This idea was studied i n three ways: histograms were prepared for frequencies of vein orientations in mines of the Slocan and Slocan City camps, an equal area stereonet plot was constructed on the Slocan City data, and the main vein strike and dip were plotted on a map. The plot map revealed patterns that were not STRK-DIP 7 AYLWIN -f- PEAK 70. CO f _2fiS SUOCAN -f- CITY _i2H 9 7 0 6-Miles 1 1 1 1———- - r — 1 r — 0(1.0 GO. 3 70.3 72.0 74.3 7C.3 VH.3 x -FIX rs PJ.J Pi!. 3 p-i J FIGURE 34 Vein Orientation P l o t 71. obvious from stereonet analysis. The plot map ( f i g . 34) displays a sub-radial pattern about a locus immediately north of Slocan City. Of course, i t is possible that this pattern of radial and scattered concentric elements i s formed from spatial arrangement of a northwest trend (similar to the Slocan camp's), an east-west trend, and a southeast trend respectively; but this would require three separate extremely localized phases of deformation affecting three adjacent areas of a homogeneous batholith. The histograms of vein strikes were useful in examining possible hypotheses based on the map plot pattern. If the strikes occurred with equal frequency from 000° to 180°, there would be no support lor a "favoured orientation" concept - but also no support for any particular spatial pattern, such as radial, randomly grouped, or concentric. The existence of one principal mode would strongly favour a single tectonic phase of deformation controlling the vein strike. Working with 112 orienta-tions from the Slocan camp, most plotted between 035° - 094°, with a strong mode at 050° - 057°; positive evidence of a principal phase of deformation. The Slocan City camp had a much more even distribution. Sixty-one strike orientations plotted with three slight highs between 030° - 100°. In contrast to the Slocan camp, there i s a low between 041° - 064°. Considering the small number of observations, however, there is no j u s t i f i -cation to rule out an even spread of strikes from due north to due south. The contoured stereonet plot of poOes to veins ( f i g . 35) i s poor evidence for any hypothesis. It reveals a broad diffuse band that FIGURE 35 Contoured Stereonet P l o t of F i s s u r e Orientations 73. effectively denies any principal vein orientation, or sets of controlled fissures. A strain ellipsoid could be f i t t e d into the nebulous pattern of highs, but with l i t t l e or no validity. Speculation on many topics could be attempted to explain the apparent radial pattern, but the concepts not ruled out by age relation-ships are dubious. Br i t t l e fracture of the rocks due to simple erosional unloading i s possible, but any regional pattern i n the relatively iso-tropic rocks of the batholith remains unexplained - as does the f i l l i n g of the veins with ore and gangue minerals. Ross and Kellerhals (1968) proposed that the Kootenay Arc was the result of interaction between a long term phase-one deformation that pro-duced a recumbent geanticline closing to the east i n the Slocan, and a relatively short phase-two deformation that refolded the earlier structure into an open synform. Fractures are common orientated parallel with, and normal to the trend of the Kootenay Arc rocks, which bend around with the Slocan area as a core. Unfortunately, there i s again no reason against both sets of fractures being equally developed across the entire area. The age relationships, however, are conclusive; deposition and subsequent phase-three deformation of the Slocan Group (Triassic) occurred before the intru-sion of the veins' host Nelson batholith (tentatively dated at 162 million years, approximately Middle Jurassic (Nguyen, Sinclair, and Libby, 1968)); long after both phase one and phase two deformations had ceased. A radial fracture pattern i s often the result of doming (or sub-sidence). The Vahalla Gneiss Dome (Reesor, 1965) i s situated directly across Slocan Lake from the radial pattern in the batholith; i t , however, 74. i s probably the result of two earlier deformations. The dome would have to be activated upwards in the Cretaceous or early Tertiary to account for the fracturing. It seems far more lik e l y that the mineralization i s associated directly with the Nelson batholith. There is much evidence supporting successive pulses of mineralization; but nothing supports a late injection at depth beneath the western margin of the consolidated batholith, to account for the radial fracturing that accommodates the mineralization. MINERALOGY PLOTS The mapping of mineralogy has been established as the most useful of the plotting attempts. After ores from each mine had been examined visually and by opaque microscopy, each mineral was assigned a code number representing i t s percentage volume of the complete vein. The resulting map i s ideal for either colour coding or simple hand contouring. Mineralogy plots assist i n answering questions about correlation between metal grades and minerals. Which minerals indicate specific highs in each metal? What, i f any, pattern of mineral zoning exists throughout the camp? A color coded map of sphalerite ( f i g . 36) displays a central high, with lows to the south, barring one anomalous high sphalerite skarn deposit (Piedmont mine) to the southwest. This plot should be compared to the hand-contoured version, ( f i g , 4), and to the very different zinc metal contour (fi g , 39) and trend surfaces (figs. 50-52). -^-Aylwin Peak % Slocan City LEGEND - greater than 15% ' - II to 1 5 % - 6 to 1 0 % - 2 to 5 % - 0 1 to 1% - less than 0 1 % 0 u 2 3 1 Miles FIGURE 36 Color Coded Sphalerite Distribution Plot CHAPTER SIX MACHINE CONTOURED PLOTS OP METAL GRADES AND RATIOS 76. INTRODUCTION Computer controlled contouring techniques vary widely (e.g. Smith, 1968), so i t i s imperative to have a clear understanding of the contouring procedures employed i n order to evaluate the results. Virtually a l l methods dealing with irregularly spaced data f i r s t superimpose a grid over the area to be contoured, assign nev; values to grid intersections according to some pre-determined method, and f i n a l l y contour the data at designated contour intervals. One should be aware that the generation of a regular grid for contouring involves some smoothing of the original data. The method of machine contouring used here was developed by personnel at the U.B.C. computing centre and has been described i n general terms by Coulthard and Leigh (1969). This program involves superposition of a grid over irregularly spaced data with new "smoothed" values genera-ted for each grid intersection. These new values are obtained by dividing the area about each grid intersection into octants and determining the weighted average of the nearest real control points i n each octant. Weighting i s proportional to the inverse of the square of the distance from grid intersection to appropriate control points. If more than four consecutive empty octants are encountered, the edge of the area to be con-toured i s recognized and contouring stops. The U.B.C. program provides for a wide variation i n scale, allowing output of maps for comparison with a variety of pre-existing data such as aeromagnetic maps, geological maps, and so on. It permits a choice 77. of contours, and provides a numerous assortment of coded symbols suitable for reference axes, notations, and important locations (ci t i e s , mountain peaks, mine sites). The program i s attractive for application to a wide variety of types of geological data; and where control points are modera-tely uniformly distributed, i s very similar to results of r o l l i n g mean analysis (e.g. Nichol, Garrett, and Webb, 1969; Bayrock and Pawluk, 1967). The contouring program does, however, contain problems that can be encountered. The most significant of these i s the generation of false con-tours, particularly i n regions where l i t t l e or no sample control exists. These can generally be spotted readily i f the relevant control stations have been plotted, as false contours occur in areas with no real data. A similar problem i s one of extreme edge effects. Fortunately, these are generally minor as the program does not attempt to extrapolate beyond the area outlined by the data. APPLICATION TO SLOCAN CITY DATA FILE Two types of variables have been analyzed i n computer-derived contour plots; (l) simple variables such as tonnage and average metal grades; and (2) more complex variables such as metal ratios of average mine grades. A l l plots were output to a common scale for ease of compari-son. Purpose of the study was to evaluate the use of average metal grades in studying metal zonation (cf. Freeze, 1966). It i s important to note that average metal grades represent a relative concentration level for various deposits irrespective of their 78. size. Furthermore, average grade contour maps need not correspond with mineral abundance maps; due i n part to the frequent presence of a given metal i n more than one mineral. Silver, an extreme example, occurs p r i n c i -pally i n the common minerals tetrahedrite, argentite and native silver; with only minor amounts in the rarer ruby silvers, stephanite, etc. Linear correlation between mineral abundance and average assay values are shown i n Table VII. Those coefficients significant at the 5$ level are indicated. These correlations are useful as an aid to visual analysis of the computer output maps of metal grades and ratios, a dis-cussion of which follows. TABLE VII. Correlations between Mineralogy and Metal Grades (Arithmetic), Slocan City Camp, B.C. MINERAL SILVER LEAD ZINC GOLD Galena (58)* 0.1343 (57) 0.5371 (44)** 0.2677 (3l) -0.1925 (3l) Sphalerite (55) 0.2629 (54) 0.4431 (43) 0.5166 (31) -0.2524 (28) Pyrite (59) -0.2086 (57) 0.3727 (36) 0.2538 (25) 0.2395 (40) Tetrahedrite (35) 0.0640 (34) -0.0960 (26) 0.3335 (20) -0.4069 (2l) * - figures i n parentheses are the observed frequencies for each category. ** - underlined correlations are significant at the 5$ level. Silver Contoured silver values (fig.37) plot in an irregular central high, orientated slightly towards the northwest. Lows occur about the perimeter. Highest values are found i n the Hampton (lOO tons grading 487 oz.Ag/ton), Evening Star (95 tons grading 363 oz.Ag/ton), and Coronation (2 tons grading 380 oz.Ag/ton) deposits. There i s a positive correlation between silver and 79. both sphalerite and galena (though surprisingly not significant for galena). Pyrite correlates negatively with silver. Native silver, argentite, chalco-pyrite, tetrahedrite, and ruby silvers each correlate only slightly with the silver assay plot. This probably implies that the dominant silver' values occur in different minerals from place to place in the camp. Lead Average lead assays (fi g . 38) form a high across the central part of the camp, with an additional northwest high caused by the Coronation property with ore grading 20$ lead. Exceptional highs occur at the Speculator (293 tons 22.6$ lead) and the Two Friends (l968 tons 44.7$ lead) mines. Both galena and sphalerite correlate strongly with the lead assays. There i s some minor positive correlation between lead and the following minerals, on the basis of visual comparison of plots: native silver, tetrahedrite, argentite, and chalcopyrite. Pyrite has a s i g n i f i -cant negative correlation with lead. Zinc Zinc values (figure 39) form a pronounced trough orientated north-westerly, with the lowest values along the southwest side. Highs appear to the southwest, and at the Enterprise mine (12,274 tons grading 21.9$ zinc). The Piedmont (527 tons grading 14.8$ zinc), and the Dayton (26 tons grading 14$ zinc) are the other high grade zinc producers. Apart from sphalerite no other minerals correlate moderately with zinc; but pyrite, % 1 - » , —I— 1 1 1 1 1 1 a i l I'J 0 U.O MO 16.0 W.O 80.0 8i.3 fi« 0 X HX!.' FIGURE 37 Computer Contoured Plot of S i l v e r Metal Grades PB 0 1 2 3 Miles FIGURE 38 Computer Contoured Plot of Lead Metal Grades Miles i i iu o ~u.i> MU TO!O W.O aa.a X-HXIS FIGURE 39 Comnuter Contoured Plot of Zinc Metal Grades 83. FIGURE 40 Computer Contoured Plot of Gold K e t a l Grades (x 10^) 84. tetrahedrite, galena, and chalcopyrite i n that order have some slight positive relationship. There i s a good chance that the early penalty on zinc values exacted by the smelters may have distorted the zinc patterns, since even the sphalerite plot disagrees with much of the metal assay contoured surface. Gold Gold ( f i g . 40) i s remarkable for plotting strong highs to the north and southwest, around a well defined central low. The entire pattern i s exaggerated towards the north by the Golden property ( l ton grading 5 oz.Au/ton). It i s flanked, however, by the L i t t l e Daisy, the L.H. property, and the Rocklands - a l l with substantial gold values. The Morning Star (27 tons grading 1.68 oz.Au/ton) i s on the western rim of the camp, while the Evening Star (95 tons grading 1.25 oz.Au/ton), Chapleau (326 tons grading 2.9 oz.Au/ton), the Crusader, the Alpine, the Oro Fino, and the Skylark and Ranger properties spread across the southern extremity of the camp. Pyrite correlates to a surprising degree with the gold netal values. Silver/Lead The ratio of silver to lead ( f i g . 41) forms a rather vague plot with random highs scattered around the map area. Since several of the mines have extremely low lead values, their moderate silver values "balloon" the ratio value. Peak values occur at the Meteor, Republic, and Duplex (Joan) properties. Of the minerals, only pyrite has a slightly positive FIGURE 42 Computer Contoured P l o t of Lead/zinc Grade Ratios RU RG FIGURE 43 Computer Contoured Plot of G o l d / S i l v e r Grade Ratios (xlO^) 88. correlation with silver/lead, whereas chalcopyrite has a slight negative correlation. Lead/Zinc The lead/zinc ratio ( f i g . 42) has a strong high i n the western central area, produced by the values at such mines as the Ottawa, Arlington, Speculator, and Two Friends. Pyrite correlates negatively with this ratio, whereas both tetrahedrite and chalcopyrite have a slight positive corre-lation with lead/zinc. Gold/Silver There i s a great similarity of pattern between gold, and gold/ silver; due to the peripheral highs of gold and the central high of silver. The pattern of north-south highs and a central low i s repeated - but the west as well as the east i s now low. High values of gold/silver (fig.43) come from the Oro Fino, Alpine, Marmion and Maryland, L i t t l e Daisy, Morning Star, and L.H. properties- For the minerals: chalcopyrite has a negative correlation and pyrite has a slight positive correlation with gold/silver. DISCUSSION Computer contouring i s an efficient timesaver that produces relatively unbiased contour maps of variables such as metal values and grade 89. ratios. Versatility of the available contouring subroutines i s shown in the adjustable scale, choice of contours, and the variety of symbols; a l l of which combine to permit clear, legible computer output in a form for easy comparison to maps having a wide range of scales. In a general way the patterns obtained agree with mineral zona-tion and trend surface analyses. Variations among the different methods of data analysis are explicable in terms of (l) a given metal may be present in more than one mineral; (2) sampling error; and (3) d i f f i c u l t i e s result-ing from poor distribution of control points. The zoning of mineralogy i s substantiated by a comparison to these metal grade patterns. Lead, and now silver, plot i n strong core highs. The anomalous low i n zinc metal grades(opposed to the sphalerite d i s t r i -bution) must have been caused by the early smelter penalties. Contoured gold assays match the zoning of pyrite. Gold was probably deposited as tiny grains, trapped against successive faces i n the developing pyrite crystals. The apparent zoning could be considered either concentric or perhaps semicircular, since the gold and gold/silver contour patterns remain low toward the east. 90. CHAPTER SEVEN TREND SURFACE ANALYSIS INTRODUCTION Trend surfaces themselves are smoothed "best f i t " polynomial surfaces - computed i n much the same way as a least squares line i s f i t t e d to a two dimensional graph. The f i r s t degree equation i s necessarily a plane, either horizontal or t i l t e d in some direction. Quadratic (second degree) surfaces are regular domes, saddles, or basins; though they can be elongated into ridges or troughs. Cubic (third degree) equations plot in interacting "dome and basin" surfaces. The quadric and higher degree equations become progressively more capable of adapting to the irr e g u l a r i -ties in the original data. The total variance i s calculated for every set of data, and the amount of variance accounted for by each successive equation i s measured against i t to give the coefficient of determination; a measure of the accuracy of the equation i n explaining the variation i n the original data. The usefulness of the various trend surfaces differs. The f i r s t and second degree polynomials can point out a tendency to higher values in some direction (such as a hypothetical increase i n metal grades towards the Slocan camp to the north), or indicate generalized centers of minera-lizati o n . The contoured residuals to these planes often give a good approximation of the higher degree surfaces, and compare with the computer plots. Other hidden patterns may be revealed: the plot of second degree 91'. residuals for silver metal grades ( f i g . 45), for example, shows a vague radial pattern similar to that of the fissure orientations ( f i g . 34). The quadric or pentic surfaces are useful as a comparison to the computer con-toured plots, i n appreciating the effect of greater smoothing, and detect-ing the extreme highs or lows which may be deforming the results of both techniques. Interpretation of the trends i s essential, once the results are classified as either basic trend with anomalies, or a smoothed surface equivalent to contouring. Trend surface analysis i s ideal for the appreci-ation of anomalies and/or inherent trends i n geochemical, aeromagnetic, or sediment analysis maps: i s there perhaps a change in the underlying rock type, or does one sheet of sediment derive from several different source areas? For the Slocan City metal grades, the technique hopefully has indicated the anomalously rich areas and a general center of minera-lization, as well as smoothed maps similar to the contoured values. Results presented in this section are trends based on logarithms to base 10 of original variables (Table VIII), as was indicated to be essential by histogram analysis of data. The logarithmic surfaces, though very similar to the arith-metic trend surfaces i n appearance and positioning, explain much more of the variation i n the original data; as would be expected from the shapes of the histograms for arithmetic and logged data. The writer was forced ' to choose the third degree trend i n certain values since the higher order surfaces had "blown up" in an attempt to match the input data. -The f i t t e d surface undulates in wild domes and troughs where the data might best suit 92. Table VIII. Slocan City Trend Surface Accuracy Measures VARIABLE Silver (oz/ton) Lead {%) Zinc (fo) Gold (oz/ton) Gold/Silver Silver/Lead Lead/Zinc ORDER OP POLYNOMIAL SURFACE 4 3 3 4 3 3 4 LOGARITHMIC R COEFFICIENT OF DETERMINATION 0.45 0.67 0.23 0.48 0.32 0.56 0.81 0.90 0.64 0.80 0.17 0.41 0.47 0.69 ARITHMETIC R COEFFICIENT OF DETERMINATION 0.18 0.42 0.08 0.28 0.29 0.54 0.40 0.63 a simple f l a t plane. Characteristically, this condition leads to enormous highs or lows in the areas of poor data coverage. A quick test of the r e l i a b i l i t y of any surface can be made by collecting the residuals i n the form of a histogram. If they closely approximate a normal distribution, then the surface i s more than l i k e l y the true "best f i t " desired. The polynomial trend surface program used figures with five decimal places,but even so the coefficients of higher order terms are often too small to register. The x and y terms involved are the UTM easting and northing coordinates used to locate each mine site. Any values of the selected variable recorded on the following trend maps should be transformed by taking the antilog - except for negative values. There i s no such logarithm as the -0.07 recorded on the second degree trend for lead ( f i g . 47). The computer handles negative logs by considering them as absolute values i n a negative direction from 93. zero. This means that simple addition can be used to increment an i n i t i a l log value whether i t i s negative or positive. Each negative value has a true mantissa equal to the absolute value to the next lower unit; which becomes the characteristic. For example, -0.07 becomes 1.93, the antilog being 0.85 percent lead. The residual maps are contoured by hand, with the units being plus or minus one standard deviation; of the data about the chosen sur-face. The importance of the residuals can be estimated from the coefficient of determination and the total variation included i n the error measures for each trend chosen; the unexplained variation makes up the residual map. METAL ASSAY TREND SURFACES Silver Trend Surfaces The second degree trend surface ( f i g . 44) forms a dome with i t s long axis aligned northwesterly. The residual ( f i g . 45) seems to correlate with the plot of vein orientation, radial from a point offshore i n Slocan Lake. There i s no resemblance betweenihe residuals and higher order sur-faces. The fourth degree shows a definite central silv e r high, occupying a sub-triangular area t i l t e d slightly west of north ( f i g . 46). The southern highs are suspect; i n the third degree surface they formed lows, and i n any case the data coverage i s scanty. 94. Table IX. Error Measures and Equations for Silver Trend Surfaces Surface SECOND FOURTH Standard Deviation 0.59 0.54 Variation not Explained by Surface 24.28 20.04 Coefficient of Determination 0.336 0.452 Total Sum of Deviations about the Mean i s 36.55 units. Equations: Quadratic Z = - 51.37829 + 0.12279(x) + 0.10085(y) - 0.00007(x2) - 0.00008(xy) - 0.0001l(y 2) Quadric Z = - 1553-50833 + 9.56999(x) - 8.00304(y) - 0.02277(x2) + 0.04302(xy) - 0.02799(y2) + 0.00002(x5) - 0.00007(x2y) + 0.00003(y5) 95. FIGURE 44 Second Degree Trend Surface for Silver Metal Grades (log i n ) FIGURE 45 Contoured Second Degree Residuals for Silver Metal Grades FIGURE 46 Fourth Degree Trend Surface for Silver Metal Grades (log 10) 98. Lead Trend Surfaces The second degree trend surface ( f i g . 47) shows a dome aligned toward the northwest, parallel to that displayed by the corresponding silver trend. The residual plot, however, has a northeasterly orientation ( f i g . 48). The third degree trend ( f i g . 49) reveals a sub-triangular central dome skewed slightly northwest. A minor tendency towards the southwest i n the third trend and the second degree residuals i s controlled by very few mines. Table X. Error Measures and Equations for Lead Trend Surfaces Surface SECOND THIRD Standard Deviation 0.70 0.75 Variation not Explained by Surface 28.59 25.56 Coefficient of Determination 0.146 0.237 Total Sum of Deviations about the Mean is 33.49 units. Equations: Quadratic Z = - 35.42935 + 0.07712(x) + 0.06474(y) - 0 .00004U 2 ) - 0.00005(xy) - O.00O06(y2) Cubic Z = - 800.58884 + 3-6l72l(x) - 2,12818(y) - 0.00536(x2) - 0.00552(xy) + 0.00059(y2) 99. FIGURE 47 Second Degree Trend Surface for Lead Ketal Grades ( l o g ^ ) 100 FIGURE 48 Contoured Second Degree Residuals for Lead Metal Grades Miles x - see p.92 FIGURE 49 Third Degree Trend Surface for Lead Metal Grades (log 102. Zinc Trend Surfaces The zinc trend surfaces are somewhat anomalous; both second ( f i g . 50) and third degree trends show a strongly developed trough-like central low, orientated toward the northwest. The second degree residuals ( f i g . 51), and to some extent the third degree trend ( f i g . 52), indicate a possible central high within the trough. The distribution of zinc assay trends i n a parallel inversion of the silver and lead highs seem to support a distinctly different source, or control, of the zinc from that of the lead or silver. Table XI. Error Measures and Equations for Zinc Trend Surfaces Surface SECOND THIRD Standard Deviation 0.90 0.79 Variation not Explained by Surface 26.58 20.54 Coefficient of ' Determination 0.126 0.324 Total Sum of Deviations about the Mean i s 30.40 units. Equations: Quadratic Z = 15.O8563 - 0.03184(x) - 0.06876(y) + 0 . 0 0 0 0 2(x 2) + 0.00008(xy) + 0.00004(y2) Cubic Z = 1205.76844 - 3.71594(x) - 4.85029(y) + 0 . 0 0 3 5 4 U 2 ) + 0.01227(xy) + 0.00127(y2) - 0 . 0 0 0 0 l(x 2y) x - see p.92 FIGURE 50 Second Degree Trend Surface for Zinc Metal Grades (log l 0 ) FIGURE 51 Contoured Second Degree Residuals for Zinc Metal Grades 105. FIGURE 52 Third Degree Trend Surface for Zinc Metal Grades (log , n) 4 106. Gold Trend Surfaces Both second ( f i g . 53) and fourth degree ( f i g . 55) trend sur-faces show a definite central low for gold assay values. The second degree residuals ( f i g . 54) plot i n a vague radial pattern, also with a central low. The basin-like low opens to the east, but this may be an indication of scarcity of control points i n the eastern margin of the map. Table XII. Error Measures and Equations for Gold Trend Surfaces Surface SECOND THIRD Standard Derivation 0.61 0.41 Variation not Explained by Surface 16.14 7.47 Coefficient of Determination 0.603 0.816 Total Sum of Deviations about the Mean i s 40.67 units. Equations: Quadratic Z = 46.83376 - 0.0814(x) - 0.13268(y) + 0.00003(x2) + 0.00008(xy) + 0.00022(y2) Quadric Z = - 13832.5271 + 90.81558(x) - 58.8326(y) - 0.2142(x2) + 0.21749(xy) + 0.05256(y2) •. + 0.00022(x3) - 0.00026(x2y) - 0.00018(xy2) + 0.00006(y5) AYLWIN PEAK x - see p.92 FIGURE 53 Second Degree Trend Surface for Gold Metal Grades (log FIGURE 54 Contoured Second Degree Residuals for Gold Metal Grades FIGURE 55 Fourth Degree Trend Surface for Gold Metal Grades (IOQ|Q) 110. Lead/Zinc Trend Surfaces The second degree trend surface ( f i g . 56)forms an elongate dome orientated northwesterly. The fourth degree trend and the residuals from the second degree surface, however, both indicate a strong positive anomaly in the central zone of the camp (figs. 58, 57). This seemed to n u l l i f y the high plotted i n the zinc second degree residuals ( f i g . 51), but a close check revealed the lead/zinc high occurred immediately south, i n an area of rather low zinc values. This combined with the extremely high lead values i n the area to develop the strong high apparent i n the lead/zinc surfaces. Other than this, there seems to be a good correlation between lead and zinc values, with the lead always more abundant. Table XIII. Error Measures and Equations for Lead/Zinc Trend Surfaces. Surface SECOND FOURTH Standard Deviation 0.44 0.34 Variation not Explained by Surface 6.25 3.93 Coefficient of Determination 0.168 0.477 Total Sum of Deviations about the Mean i s 7.51 units. Equations: Quadratic Z = - 39.18293 + 0.0904(x) + 0.07176(y) - 0.00005(x2) - 0.00007(xy) - 0.00006(y2) Quadric Z = - 14825.72105 + 54.48539(x) + 105.26804(y) - 0.05815(x2) - 0.44128(xy) + 0.05906(y2) + 0.0000l(x5) + 0.0006(x2y) - 0.00012(y5) 111. x - see p.92 FIGURE 56 Second Degree Trend Surface for Lead/Zinc Grade Ratios ( l o g m ) FIGURE 57 Contoured Second Degree Residuals f o r Lead/zinc Grade Ratios 113. x - see p.92 FIGURE 58 Fourth Degree Trend Surface f o r Lead/Zinc Grade Ratios ( log. n ) 114. Gold/Silver Trend Surfaces Only the third degree trend (Fig. 59) and residuals (Fig. 60) are shown. Higher order surfaces contained highly attenuated highs and lows in areas of l i t t l e control. The second order surface had the same general trend as does the third. The basic pattern i s a basin, open some-what to the east; similar to the gold trend surface patterns (Figs. 53» 55). The third degree gold/silver residuals show a series of highs and lows elongate i n an easterly direction. Table XIV. Error Measures and Equations for the Gold/Silver Trend Surface Surface THIRD Standard Deviation 0.79 Variation not Explained by Surface 25.96 Coefficient of Determination 0.643 Total Sum of Deviations about the Mean i s 72.65 units. Equation: Cubic Z = 1447.42932 - 5.92635U) + 1.36989(y) + 0.0081l(x2) - 0.0037(xy) - 0.00036(y2) 115. FIGURE 59 Third Degree Trend Surface for Gold/Silver Grade Ratios, (log (Au/Ag 116. FIGURE 60 Contoured Third Degree Residuals for Gold/Silver Grade Ratios 117. Silver/Lead Trend Surfaces The silver/lead fourth degree trend has not been included, as i t was controlled completely by the density of data coverage. This loss of v a l i d i t y i s often indicated by a leap i n the amount of variation "explained"; the third degree surface accounts for 16.6$ of the deviation (Table XV) while the fourth covered 43.6$. The third degree surface forms a f l a t dome indicating almost no discernable trend (Fig. 61), while i t s residuals (Fig. 62) correlate almost perfectly with the residual plot from the second degree lead assay trend (Fig. 48) in outlining the high lead zones. Table XV. Error Measures and Equation for the Silver/Lead Trend Surface. Surface THIRD Standard Deviation 0.76 Variation not Explained by Surface 26.27 Coefficient of Determination 0.166 Total Sum of Deviations about the Mean i s 31.49 units. Equation: Cubic Z = 216.30049 - 1.3363U) + 2.06027(y) + 0.00237(x2) - 0.00513(xy) - 0.0006l(y 2) 118. FIGURE 61 Third Degree Trend Surface for Silver/Lead Grade Ratios (log ) 119. FIGURE 62 Contoured Third Degree Residuals for Silver/Lead Grade Ratios 120. SUMMARY The general results of the trend surface analysis have been most interesting. Of the simple second or third degree surfaces, four have shown a strong northwesterly orientation: silver, lead, and lead/zinc plot as elongate domes; while zinc, surprisingly, forms a trough. Silver/ lead shows as a very f l a t and diffuse dome slightly higher to the north. Only the gold and gold/silver trend surfaces are definitely opposed, both revealing a well developed central low opening towards the east. Basically, then, there seems to be a high core of lead and silver values tending northwest; with the gold occurring to the north, west, and south. The exception to this rule i s the northwest tending trough of zinc assays. The residuals from lower degree surfaces often end up containing much of the variation i n the original data; and are correspondingly important. The silver and gold residuals both show a vague radial trend from a point i n Slocan Lake just north of Slocan City, roughly matching the main vein orientations. Neither gold nor silver residuals look like the related fourth degree surfaces. Both lead and zinc residuals resemble each other, except for a central area where high lead over-rules low zinc developed i n the lead/zinc residual plot. The zinc and more strongly the lead residuals plot with a northeasterly orientation. The gold/silver residuals display a non-committal series of east-west r o l l s . Naturally enough, the hand contoured residuals usually relate i n some way to the higher degree trend surfaces. The fourth (or third) degree surfaces are normally best 121. employed as smoothed versicna of the contoured raw data surfaces. The gold and g o l d / s i l v e r show strong central lows with peripheral highs to the south east, and north. The f o u r t h degree s i l v e r and the t h i r d degree lead trend both have the same sub-triangular c e n t r a l high orientated s l i g h t l y north-west. The fourth degree lead had a spurious southern high and northeast low that gave the o v e r a l l surface a d e f i n i t e northeasterly o r i e n t a t i o n , contrary to i t s own second and t h i r d degree surfaces. The fourth degree surface f o r s i l v e r / l e a d was equally spurious, though i t s northeasterly tendency was a high-for-low i n v e r s i o n of that of lead. Fourth degree zinc developed a c e n t r a l high, threatening to cut across the northwesterly trough shown i n the second degree trend. For the o v e r a l l view of metal assay zoning ( F i g . 6 3 ) , the gold and g o l d / s i l v e r i n d i c a t e a semicircular halo of high assays north, west, and south; surrounding a d e f i n i t e core of high s i l v e r and lead. Zinc's trend seems r e l a t e d to both patterns; i t has a c e n t r a l low c u t t i n g across the map towards the northwest; but the centre has a r e s i d u a l high. Both ends of the trough-like low occur i n areas of poor data coverage. There i s uncertainty as to the e f f e c t of time on the anomalous pattern of zinc assays; gold, s i l v e r , and lead were recorded from the i n c e p t i o n of the mining camp, whereas zinc values were not honoured by the smelters u n t i l approximately 1905. 122 / / / / / I. tit ir— \ \ \ / / / / A I / •i±z— \ V -\ V ,/-y-Aylwin Peok ^ \ \ —^ -N A \ \ \ \ 1 l / | II lg y ' / I V Slocan City \ ^ \ - High Silver Trend - High Lead Trend \ \ \ \ s T 7 - - - High Zinc Trend \ [ J ] - High Gold Trend / FIGURE 63 Idealized Composite Diagram of Inferred Zonal Distribution of Metal Grades 123. CHAPTER EIGHT MULTIPLE REGRESSION ANALYSIS INTRODUCTION The simplest form of regression analysis i s the f a m i l i a r "least squares" or "best f i t " technique: i n which a l i n e i s drawn through a series of points representing the relationship of a (dependent) variable upon another (independent) variable. Ideally, observed values of the dependent variable remain normally distributed about the predicted value, for any value of the independent variable; i f an i n f i n i t e l y large number of samplings were plotted, t h e i r mean values would a l l plot, or regress, on the best f i t l i n e . In l i n e a r regression, the l i n e i s such as to mini-mize the sum of the distances (squared) from each data point to the l i n e . Multiple regression extends the concept to several independent variables. Judgement of the accuracy of a re s u l t i n g equation i s both desireable and necessary; i f even the best equation f a i l s to account s i g -n i f i c a n t l y f o r the va r i a t i o n , then the technique i s useless. A rule of thumb assessment of a multiple regression equation can follow from a study of the multiple correlation c o e f f i c i e n t s between the dependent variable and every other ( S i n c l a i r and Percy, 1969),(Table XVl). In correlation, a l i n e that matches the data points perfectly, and has either a positive or negative slope ranks as plus or minus unity, respectively. A completely random scatter of points on the graph means zero correlation. The fewer the data points, the less r e l i a b l e i s the 124. Table XVI. Correlation Matrix of Logged Variables, for 22 Mines i n Slocan City Camp, B.C. VARIABLE TONS SILVER LEAD ZINC GOLD fo SULPHIDES TONS 1.0000 SILVER -0.1328 1.0000 LEAD -0.0421 0.4582 1.0000 ZINC -0.2714 0.3587 0.9198** 1.0000 GOLD -0.4538 -0.3816 -0.5387* -0.3517 1.0000 fo SULPHIDES 0.4687 -0.0787 0.4409 0.3442 -0.5600* 1.0000 **— Significant at the 1% level * - Significant at the 5f° level correlation coefficient. A more useful error measure i s the square of the correlation coefficient, called the coefficient of determination (R ); a quantitative measure of the proportion of the total variance explained by the equation. The total variance i s the variation of the dependent variable about i t s own mean - and from this can be subtracted the varia-tion unexplained by (or about) the equation, to obtain the coefficient of determination.The goodness of f i t i s merely the coefficient of determina-tion multiplied by 100; a percentage of the total variance. ESTIMATE OF SLOCAN CITY MINE VALUE The purpose of a l l stepwise multiple regression equations cal-^ culated (using standard subroutines from the s t a t i s t i c a l package program TRIP of the Computing Centre, U.B.C.), was principally one of establishing an empirical relationship between some measure of value (such as tonnage) 125. and other easily measurable variables (Orr and Sinclair, 1971). If such a relationship can be shown, there are obvious advantages i n providing a means of re-evaluating known deposits, and evaluating the potential of newly discovered deposits. In the present case a natural f i r s t choice for the dependent variable was total dollar value for each mine; but this figure contains hidden s t a t i s t i c a l flaws (Sinclair and Wordsworth, 1970). If several mines had values i n silver only, their dollar value would be linearly dependent upon silver grades; whereas other mines with a different predominant metal would have a value dependent on i t . Since dollar value was not i n -cluded on the data f i l e , a special subroutine had to be written to calcu-late i t ; and the presence or absence of specific metal grades tends to produce a b u i l t - i n variation. Furthermore, dollar value i s a purely a r t i -f i c i a l variable which changes, sometimes drastically, over the short term with changes in metal prices. The variable f i n a l l y chosen was tonnage. This may seem to ignore value as such, but i t i s certainly a measure of relative size; which i s one of the more important factors i n establishing the "value" of a deposit i n this area of relatively high grade deposits. A prediction of value was achieved i n four steps. A small group of mines with relatively complete data was selected arb i t r a r i l y , an equa-tion calculated relating tonnage to other variables, and this formula ( i n -cluding only the most decisive variables, by a process of stepwise dis-carding of unrelated factors) was applied to the entire mass of data. The predicted value was then compared to the observed value by a simple graph, (Fig. 6 4 ) . 126. The most interesting mines, of course, were those with low observed and high calculated tonnages; where i s the ore that should have been there? The major d i f f i c u l t y encountered i n applying the method was the scarcity of control points for which a l l independent variables were ava i l -able. To counteract this, various substitutions were attempted. I n i t i a l l y , any blank was replaced with a reasonable figure, such as a trace amount, a unit value, or the mean value. Further attempts involved calculation of subsidiary multiple regression equations for each of zinc, lead, and silver; against a l l other variables except themselves and tonnage. For example, the derived lead equation (based on 17 data points, goodness of f i t 89.64$) was: Log 1 Q($ Lead) = - 0.283 + 0.785(Log 1 Q($ Zinc)) - 0.142(Log10(0z.Au/ton)) + 0.387 (Log 1 Q(Total Years of Production)). Log^($ Lead) had a standard error of 0.386, and the equation was signi-ficant at the 1$ level. The increase i n goodness of f i t using these more sophisticated substitutions for blank metal grades, however, was i n the range of only one or two percent. The f i n a l equation for mine value in the Slocan City camp was derived from the data of 22 mines, with a 55.25 percent goodness of f i t . Log1Q(Tonnage) = 0.265 + 1.072 (Log 1 0($ Lead)) - 1.353 (Log 1 Q($ Zinc)) + 1.756 (Log 1 Q($ Volume Sulphides i n Vein)) This equation (significant to the 1$ level) was used to calculate the expected tonnages for a second group of 46 mines. The linear correlation between observed and expected tonnages (Fig. 64) for these mines was +0.6003. The chosen equation i s practical i n that two of the variables 127. are based on ore assay values, while the other i s a general mineralogical variable easily measured i n the f i e l d . The variables are a l l independent of each other, and of any measure of time or tonnage. Any equation that used a variable linearly related to the dependent variable resulted i n a near perfect f i t ; unfortunately the best equation always ended up comple-tely controlled by this variable alone. Ideally,'one could predict with a measureable degree of accu-racy the expected tonnage yield of a new property from the f i r s t shipment of ore. For example, a typical prospect might grade on the average 6.8$ lead and 1.0$ zinc; i n a vein containing 28$ by volume sulphides. The most l i k e l y prediction of tonnage for this prospect using the above multiple regression equation would be 5,000 tons; with upper and lower 50$ confidence limits at approximately 19,540 and 1,280 tons. 128. 40 o Ui a> 30 o c c o TD a> 20 Ui _Q o 10 00 10 20 30 40 C a l c u l a t e d T o n n a g e s ( i o g l 0 ) FIGURE 64 Scatter Diagram of Calculated versus Observed Tonnages for 46 Mines 129. CHAPTER NINE CHI SQUARE ANALYSIS INTRODUCTION Relatively few published examples exist i l l u s t r a t i n g the use of chi square methods for establishing significant relationships among various characteristics of ore deposits. Peach and Renault (l965) examined the dependence of types of molybdenite deposits i n Br i t i s h Columbia on type of wallrock. The contingency table they used (Table XVII) was derived entirely from a literature survey. Each pigeon hole i n the table contains the number of deposits of a particular type characterized by a certain type of wallrock. They were able to show that molybdenite deposits are dependent on general rock type; i n particular molybdenite deposits are associated with plutonic masses. Table XVII. Condensed Contingency Table of Rock Type versus Deposit Type for British Columbia Molybdenite Occurences- (after Peach and Renault, 1965). Deposit Type Quartz Veins and Lenses Fractures and Shears Disseminations Contact Breccias Column Totals Rock Type Intrusions and A l l Other Rock Pegmatites Types 26 (31.0)* 16 15 5 _L 65 (11.9) (10.7) (7.75) .(3.58) 26 (22.0) 4 (8.06) 3 (7.26) 8 (5*24) 3_(2.42) 44 Row Totals 52 20 18 13 6 109 Grand Total * Figures i n parentheses are the theoretical frequencies. 130. Chi square tests involving two-way contingency tables of the type shown in Table XVII test for dependence or independence of the variables l i s t e d i n rows versus those lis t e d i n columns. The .two variables are i n -dependent i f , for example, the ratio of variables in a l l rows are approxi-mately the same, or, i f the ratio of variables in a l l columns are similar. The procedure involved i s to estimate the most l i k e l y ratio of distribution of deposits i n rows or columns by totalling both rows and columns. The expected or theoretical value for any pigeonhole i s then estimated by multiplying i t s row total by i t s column total, and dividing the product by the grand total. A chi square value for the entire contingency table i s arrived at by totalling, for a l l pigeonholes, the square of the difference between observed and expected values, divided by the expected value. \ ~ m n 0 x2 = r: r ((<>..- E. .f / E. .) j=i 1=1 i j 1 3 ' xy If this measure of the deviation i s low, then the variables are independent. If high, the variables are dependent. C r i t i c a l chi squared values that distinguish dependence from independence for various levels of significance can be obtained from standard s t a t i s t i c a l tables such as those i n Krumbein and Graybill (1965). The chi square test i s dependable and easy to apply; but there are limitations. None of the category (pigeonhole) frequencies can be less than one, and not more than 20$ of the frequencies can be less than 5« Commonly, the f i r s t arrangement of values must be recombined to yield a suitable table of frequencies. Like most other s t a t i s t i c a l procedures, the chi square test becomes more significant as the number of observations 1 3 1 . increases; the scarcer the information, the less one can derive from i t . CHI SQUARE ANALYSIS OF SLOCAN CITY DATA FILE The major purpose in applying the chi square technique to Slocan City data was to establish whether various recorded parameters were dependent or independent of some value measure of the mineral deposits. The writer's hope was that the presence of certain features would indicate relatively high mine value and thus have considerable practical application. As with the other s t a t i s t i c a l techniques described here,the variable "production to date" (in tons) was used for a value measure. In order to establish contingency tables suitable for chi square analysis i t was necessary to establish appropriate tonnage intervals. Those intervals f i n a l l y arrived at after some t r i a l and error were: I (l-lO tons), II (11-50 tons), III (51-500 tons), and IV ( greater than 501 tons). Contingency tables were prepared by running the Slocan City data deck through the card sorter to obtain any mine's card with a record of the chosen variable. These cards, i n order of tonnage, were recorded on hard copy using the card sorter and computer l i s t i n g for each data deck. Chi square values for each contingency table were calculated using a library subroutine available through the U.B.C. Computing Centre. A variety of variables were tested i n turn against the relative value measure, tonnage: including ( l ) types of associated dykes, ( 2 ) type of wall rock alteration, (3) type of gangue mineralogy, and ( 4 ) main vein orientation. Corresponding contingency tables are shown in Tables XVIII to XXI inclusive. 132. Table XVIII. Contingency Table of Deposit Size Versus Associated Dykes for the Slocan City Camp, B.C. TYPES OP DYKE TONNAGES ROW TOTALS 1-10 Tons 11-50 Tons 51-500 Tons >501 Tons B*asic Dykes 8 4 9 9 30 Aplite Dykes 4 5 5 4 18 Pegmatite and Quartz Porphyry J j _ _4_ _4_ _5_ 18 Column Totals 17 13 18 18 66 2 X = 1.901, degrees of freedom = 6, Percentile Accuracy of Dependence i s 7T. The basic hypothesis being tested i n Table XVIII i s whether or not dykes have some special relationship with tonnage, in mines of Slocan City camp. Prom a preliminary examination, i t seems obvious that f e l s i c dykes occur randomly, whereas the basic dykes conceiveably might not be. The chi square results, however, affirm that in 924$ of the cases, one would be correct in saying that the dykes in and about these mines have no connection with, or are independent of, the possible tonnage yield. No inferences can be drawn from this statement about possible relation-ships between the dykes and the actual ore minerals i n the mines. Which came f i r s t could be established by age dating, or perhaps through study-ing the structural orientation of the dykes versus the veins. Were the ores leached or remobilized by later dykes? Did early basic dykes provide a more favorable environment for precipitation of certain ore minerals ? These and other questions are s t i l l open to speculation. 133. Table XIX. Contingency Table of Deposit Size versus Type of Wall Rock Alteration for the Slocan City camp, B.C. ALTERATION TONNAGES ROW TOTALS 1-10 Tons 11-50 Tons 51-500 Tons >501 Tons S i l i c a 15 11 11 7 44 Chlorite 12 11 12 9 44 K-Spar and Pyrite 8_ 11 8 _8 35 Column Totals 35 33 31 24 123 2 X = 1.949? degrees of freedom = 6, Percentile Accuracy of Dependence is 8. Prom the evidence gathered i n the f i e l d , type of wall rock alteration appears to have l i t t l e relationship with deposit size (see Table XIX). This conclusion, unfortunately, i s far less certain than perhaps i t could be. Alteration has been identified by the presence of selected key minerals, instead of by such terms as saussuritization or s i l i c i f i c a t i o n . A single mine's records could, for example, indicate pyritization, carbonatization, and chloritization; a l l well developed. A definite problem arose i n proper classification of some minerals as either "vein" or "key alteration" forms. Very few deposits were not classifiable i n the format used; the Piedmont (Hope #2) mine is a skarn deposit with abundant garnet, calcite, and diopside; a former limestone unit within a small pendant. Even considering these problems, however, the 9 ^ accurate rejection of alteration as a guide to higher tonnage seems conclusive. 134. Table XX. Contingency Table of Deposit Size versus Type of Gangue Minerals, for the Slocan City camp, B.C. GANGUE TONNAGES ROW TOTALS 1-10 Tons 11-50 Tons 51-500 Tons >501 Tons Calcite and Siderite 9 13 10 14 46 Quart 21 20 16 11 68 Column Totals 30 33 26 25 114 2 X = 4.041, degrees of freedom = 4, Percentile Accuracy of Dependence i s 60. Insufficient data were available for chi square analysis of dolomite* barite, and fluorite (barite - 9, fluorite - 3, and dolomite - 0) values. In the calcite and siderite pigeonhole of Table XX, there i s hidden information; the siderite strongly correlates with high tonnages, whereas calcite i s independent of tonnage. Since there i s a problem of positive identification, especially for weathered dump material, calcite and siderite were considered together. In brief, a carbonate gangue i s a positive indicator of high tonnages in Slocan City camp. From this chi square test i t s e l f , however, a l l we can say i s that tonnages and gangue mineralogy (unspecified) do have some connection or dependence. Table XXI. Contingency Table of Deposit Size versus Main Vein Orientation i n the Slocan City camp, B.C. STRIKE RANGE TONNAGES ROW TOTALS 1-10 Tons 11-50 Tons 51-500 Tons >501 Tons 000°-060° 6 6 4 8 24 06l°-120° 10 5 9 2 .26 121°-180° 5 4 5 1 11 Column Totals 19 15 16 11 61 2 X = 8.40, degrees of freedom = 6 Percentile Accuracy of Dependence i s 75. 135. The hypothesis of dependence between main vein orientation and the total tonnage produced i n the Slocan City camp i s approximately 75$ accurate (Table XXI). More specific questions on this basic topic can be answered, but only with guesses. If one were interested i n a relatively o o large mine, one would probably ignore fractures striking 121 -180 . Large deposits would l i k e l y be found more often by concentrating on fractures with strikes from 000°-060°. In general, the chances of finding a mine with greater than f i f t y tons total production seem to be favorable in roughly half of the cases. CONCLUSIONS The usefulness of the chi square s t a t i s t i c a l technique can be best appreciated in a series of simple concluding statements; with v a l i d i t y measured in terms of percentage significance. Tonnage in the mines of the Slocan City camp i s : (l) not related to type of associated dyke (92-g$ significant); (2) not related to type of wall rock alteration present (92$ significant); (3) related to the gangue mineralogy (60$ significant); and (4) related to the orientation of the main vein (75$ significant). The importance of these results to an exploration geologist i s obvious. These statements form a set of regional tonnage indicators that are easy to apply i n the f i e l d . The general potential of the chi square method i s increased through i t s a b i l i t y to point out the poorer information - the collection of which should either be improved, or ignored entirely, with extra time spent on ascertaining more relevant facts. 136. CHAPTER TEN SUMMARY AND CONCLUSIONS The Slocan City mining camp i s small, covering a strip of rugged terrain along the east side of Slocan lake. Nearly a l l the veins occur i n the rocks of the Nelson batholith, which ranges in composition from fresh homogenous quartz monzonite to porphyritic granodiorite. The veins are strikingly different from those in the Slocan camp, having a different mineralogy (Cairnes, 1934, p.113) and lacking a dominant strike direction. At the time of deposition of the ore minerals, the present surface was approximately one mile beneath the then existing surface. The inter-connected network of fissures and lodes in the rock provided a natural gradation i n temperature and pressure conditions for mineral deposition. Since many of the mines have been worked for years, the total production from each represents a good estimate of average grade of the ores. The paragenesis of minerals seems relatively normal, and the distribution approximately f i t s with levels five through seven of Emmons' reconstructed vein system ( l 9 4 0 , p . 1 9 6 ) . Pyrite with minor amounts of galena and spalerite occur sparsely i n a gangue consisting primarily of quartz (with some carbonate). This i s succeeded by a core mineralization of galena, sphalerite, and silver sulphides; i n a gangue of quartz with minor amounts of siderite, calcite, and barite. Argentite and native silver are common. Chalcopyrite i s present, but in trace amounts. Exceptions to the above sequence are found in disseminated sulphide ores from the L.H., Rocklands, and Speculator mines; and in the Piedmont skarn ores. 137. The w r i t e r was unable to prove the existence of any form of v e r t i c a l zoning through a study of the enti r e camp. L a t e r a l zoning, however, revealed i t s e l f i n several minerals and some of the metal values. There seem to have been two separate pulses of m i n e r a l i z a t i o n that spread through the veins and f i s s u r e s with l i t t l e contamination from the wall rock. A primary pulse of m i n e r a l i z i n g f l u i d deposited a p a r t i a l r i n g of p y r i t e . Gold metal values follow t h i s pattern as well, almost c e r t a i n l y as minute i n t e r s t i t i a l material that formed and was trapped on the surfaces of the developing p y r i t e cubes. The c e n t r a l zone might have contained p y r i t e , but only rare r e l i c t grains remain. Perhaps the thermodynamic con-d i t i o n s v/ere inappropriate, or the chemical nature of the ore-forming f l u i d changed such that e a r l y formed p y r i t e i n the core was dissolved by l a t e r i n j e c t i o n s of f l u i d . The second pulse involved a change i n the locus of deposition, and i n the nature of the ore-forming f l u i d . Sphalerite followed by galena occupies the core zone, and has replaced part of the inner edge of the py r i t e m i n e r a l i z a t i o n . The minor minerals f a i l e d to d i s p l a y any p o s i t i v e pattern, except f o r the s i l v e r minerals c o i n c i d i n g v/ith the galena-s p h a l e r i t e high. The very sporadic nature of the ore and the l i m i t e d a b i l i -ty to c o l l e c t t r u l y representative samples (caved adits,barren v/aste dumps, etc) have s e r i o u s l y impeded the chances of assessing accurately the d i s -t r i b u t i o n of any of the minerals present i n trace amounts. I n t e r e s t i n g l y , native gold (though rare) displays no systematic pattern of occurrence i n the camp. I t may even represent a l a t e r stage of precious metal m i n e r a l i -zation, perhaps contemporaneous with chalcopyrite. Unfortunately, any 1 3 8 . such conclusions are based on the dubious identr'fication of extremely small grains as gold, instead of s i l v e r - r i c h electrum. S i l v e r and lead metal values closely follow the high indicated by galena. Zinc values are anomalous due to the high zinc penalty l i s t e d i n the smelter schedules during the early boom years of the camp. Contoured maps of metal values represent s l i g h t l y smoothed versions of the o r i g i n a l data, due to the preliminary development of a regular grid of values. Trend surfaces, however, exhibit much more smoothing and are perhaps more r e l i a b l e i n predictions of grades for spe-c i f i c mines i n the area. There i s generally excellent correlation between the patterns exhibited by the thi r d or fourth degree trend, and the shape of the machine contoured surface. In places, computer plotted contours closely resemble hand contoured residuals from the second degree surface. Trend surfaces can be grouped as to their most useful applica-tions. The second degree trends appear to indicate centers of mineraliza-t i o n . Their residuals, hand contoured, correlate reasonably well with the machine contour plots; or w i l l tend to point out possible sub-patterns i n the data, such as the fissure alignment present i n the Slocan City data and detected i n the second degree residuals for s i l v e r and gold. The fourth degree surface (or t h i r d , i n cases of poor data coverage) i s the best means of smoothing data, and produces contours that roughly p a r a l l e l those of machine contoured plots. Higher degree plots are not often a p p l i -cable, because of i r r e g u l a r spacing of control points and because the considerable v a r i a t i o n i n o r i g i n a l data forces these trend surfaces into wild distortions i n attempts to match the data more perfectly. 139. Slocan C i t y camp has d e f i n i t e mineral p o t e n t i a l , p r i n c i p a l l y f o r small operations up to a few thousand tons reserves. One of the more successful deposits of the l a s t few years has been the Freddy; owned and operated by two men. The mines, though high grade, are simply too small to i n t e r e s t the giants of the mining trade. This r e s t r i c t i o n does not, however, apply to the Slocan camp to the north. There are excellent p o s s i b i l i t i e s f o r several more ten to twenty thousand ton operations i n the camp, probably from the zone between Enterprise and Springer creeks. I t i s extremely u n l i k e l y that any present method of mining other than surface s l u i c i n g or expensive underground development would be f e a s i b l e . The computer processible f i l e of data f o r Slocan C i t y mineral deposits has proved a u s e f u l a i d i n both academic and p r a c t i c a l evaluation of the camp. Apart from permitting an easy systematic study of mineral and grade d i s t r i b u t i o n that might have been done equally well, at length, by the standard method of map preparation; i t has allowed the write r to i n -vestigate the data by a v a r i e t y of techniques that othsrwise could not have been attempted. In p a r t i c u l a r , trend analysis of metal grades and r a t i o s , c h i square a n a l y s i s , and multiple regression methods were attempted with some u s e f u l r e s u l t s as indic a t e d above. Given a s p e c i f i c area i n the camp, i t should be possible to predict with measurable accuracy the values i n metals, minerals, and tonnage to be expected. The most obvious example of t h i s would be a miner holding a block of claims on which he had found a promising vein. E s t i -mates of metal assay grades per ton would come from the value of the t h i r d 140. or f o u r t h trend surface f o r the area, modified by the i n d i c a t i o n s from the machine contoured o r i g i n a l data p l o t s . These values could then be read into the multiple regression equation f o r tonnage, to y i e l d the best pro-d i c t i o n of t o t a l tonnage f o r the mine. Better yet, a preliminary bulk sample of ore could be sent to the smelter, and the returned assays run through the tonnage equation. The mineralogy predictions would be les s accurate, as many minerals occur s p o r a d i c a l l y through the camp. Sphalerite, galena, and py r i t e d i s p l a y d e f i n i t e patterns, whereas minerals l i k e ruby s i l v e r s , native gold, chalcopyrite or native s i l v e r are l e s s predictable. More sop h i s t i c a t e d s t a t i s t i c a l techniques could be applied i n the Slocan C i t y camp, such as f a c t o r a n a l y s i s or discriminant a n a l y s i s . An expansion of the data f i l e to include deposits without recorded produc-t i o n , as well as minor prospects and showings, i s d e f i n i t e l y advised. This study has shown that these prospects can be evaluated as to economic p o t e n t i a l using assay and mineralogical v a r i a b l e s that could be obtained by r e l a t i v e l y l i m i t e d sampling and ge o l o g i c a l observations. The writer f e e l s , however, that a s i m i l a r study based on the Slocan camp would y i e l d f a r more u s e f u l and productive economic r e s u l t s . 141. BIBLIOGRAPHY Ahrens, L*H. 1954. 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Proc. of a symposium on decision-making in mineral exploration II, Engineering Programs, Extension Department, U.B.C. pp.107-120. Ediger, N,M., and W.C.Brisbin. 1967. Report of the ad hoc committee on storage and retrieval of geological data in Crnada, .in, A National System for the Storage and retrieval of Geological Data in Canada. Geol.Surv.Canada. Emmons, W.H. 1940. Principles of Economic Geology. 2nd. ed. New York, McGraw-Hill Book Co., P-196. Engineering and Mining Journal. Market Prices. February 1971. Fyles, J.T. 1967. Geology of the Ainsworth-Kaslo Area, British Columbia. B. C.Department of Mines and Petroleum Resources, Bulletin 53. Freeze, A.C. 1966, On the Origin of the Sullivan Orebody, Kimberley,BiC. C. I.M.M. Special Volume No. 8, pp.263-294. Greenwood, B. 1969. Sediment Parameters and Environment Discrimination; an Application of Multivariate Statistics. Can.J.Earth Sci. 6, pp. 1347-1358. 142 Hedley, M.S. 1947. Geology of the Whitewater and Lucky Jim Mines, B.C. Dept. of Mines, Bulletin 22. Hedley, M.S, 1952. Geology and Ore Deposits, Sandon Area, Slocan Mining Camp. B.C. Department of Mines, Bulletin 29. Hutchison, W.W., and J.A. Roddick, 1968. Machine retrieval and processing for recording geological data. Western Miner. February 1968. Krumbein, W.C., and Graybill, F.A. 1965. An Introduction to Statistical Models in Geology. New York, McGraw-Hill Book Co. Lepeltier, C. 1969. A simplified statistical Treatment of Geochemical Data by Graphical Representation, Econ.Geol.,64, pp.538-550, Little, H.W. I960. Nelson Map-Area, West Half, British Columbia. Geol. Surv.Canada, Memoir 308, McCrossan, R.G. 1969. An Analysis of Size Frequency Distribution of Oil and Gas Reserves of Western Canada. Can.J.Earth Sci., 6, pp.201-211, Nguyen, K.K., Sinclair, A.J., and Libby, W.G, 1968, Age of the Northern Part of the Nelson Batholith. Can.J.Earth Sci. 5, pp.955-957. Nichol, I., Garrett, R.G., and Webb, J.S. 1969. 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Wynne-Edwards,H.R., K.N.M.Sharma, A.F.Laurin, A* Nandi, M.M. Kehlenbeck and A. Franconi, 1970. Computerized geological mapping in the Grenville province, Quebec; jLn: Proc. of a symposium on decision-making in mineral exploration III. Extension Department, U.B.C. pp.1-21. APfcjSIIDIX Computer Listing oi£ / Slocan City Data Base (Format outlined in Tables IY and V; pp. 5 2 , 5 4 ) < < Z < u oo" OS w > 3 O o z < > "COLUMBIA LISRKRT OF BRITISH X X X X X X X X X X X X X X X X X X A X X X X X X X A X X A X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X X U N I V E R S I T Y OF 6 C COMPUTING CENTRE M T S ( A N i 2 0 i xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx RF S K G . 0 2 3 4 4 3 * * C G ^ F U T E R CENTRE WILL tit CLOSED riUNOAY FOR THE H O L I D A Y * * J S I G C R R J * * L A S T S I G N G N W A S : 1 3 : 4 1 : * 1 0 5 - 2 2 -U S E R " C R R J " S I G N E D UN A T I 3 ; 4 5 : l 5 i l l S T *SCURC£* i 71 UN 0 3 - 2 2 - 7 1 . L G G A N L i T Y D A i A DfcUi\ CARD DUE" 1 3 : 4 5 : 1 2 0 5 - 2 2 - 7 1 c C 1 G E T T G , t L I 7 3 3 2 6 4 3 2 0 0 10 10 1 1 1 1 6 5 1 5 E 5 1 . 2 0 . 4 0 38 6 C 2G0LUEN 7 4 3 2 6 1 5 0 0 0 ID 1 5.GOD 05 7 C 3 L . H.GROUP7 5 9 2 6 8 5 2 5 0 3D 2 1 6 2 1 22 1 G 9 0 5 5 N . 2 8 2 . 5 1 4 39 8 C 4R0GKLANUS73 32 5 53 900 I A 331 1 i 1 G507GS 0 . 7 0 99 9 c 5 L i i 1 LbOSY / 4 G 2 5 / 4 4 0 0 3U 51 i 1 1 . 8 5 1 . / 2 0 36 IC C 6 S L V R N U G G T 7 4 7 2 4 3 6 6 0 0 20 2 211 0 6 3 5 5 S 2 2 7 . 1 . 1 7 05 11 C / S I L V R L b A F 7 5 6 2 4 7 6 4 0 0 3D 43 i i. 0 6 5 8 4 S 1 7 . 9 6 . 7 5 7 . 2 9 51 12 C o H i u i l L D L T / 4 J 2 3 8 6 D G 0 J O 11 212 1 21 1 3 0 7 5 N 2 5 8 . 18 13 C 9 K A L I S P E L L 7 0 5 2 3 2 2 3 2 5 3A 22 2 1 3 1 4 3 0 2 0 5 5 E 2 4 0 . 9 7 14 C 1 0 W S T + E S T M T 7 o 9 l 9 6 4 3 7 5 i 5 D 4391 1 1 1 O 6 0 7 3 N 7 9 . 8 4 . 8 2 1 . 3 0 . 0 1 4 8 . 2 5 4 70 15 c 1 1 DUMA6-A03 /bui663i0u 2A 40 1 9 . 8 0 3 . 1 7 3 . 4 9 . 0 0 4 0 5 b 16 C 12NEEPAWA 7 6 1 1 6 7 4 6 0 0 60 506 1 4 1 2 0 3 0 6 5 E l 17 .2 .0.1. 730 25 17 C 1 3 E N T E R P R 1 S 7 6 4 1 8 4 4 6 0 0 1 9 U 12274 2 i 2 1 1 2 0 5 0 7 0 S 9 D . 2 1 6 . 5 2 1 . 9 . 0 0 0 5 1 . 9 7 68 18 C 1 4 M A u U U U H l u 7 3 6 l 8 06GGu 20 8 1 1 0 5 5 7 U S 2 G . 5 1 . 8 7 3 . 2 48 19 C 1 5 R I V E R S i D b 7 / 5 1 7 2 62UG 3D 22 21 1 0 4 U 8 0 E 4 4 . 4 2 . 5 0 2 . 3 i 37 2C C 1 6 P A R A - R 0 Y L 8 2 4 2 0 8 7200 3D 17 21 1 0 0 5 3 / E l l . 8 3 . 0 4 . 0 . 0 0 2 32 21 c 1 / B 0 0 M b K A N G 6 3 0 l 6 3 6 4 3 u i A 5 l l 1 / 3 8 0 b 4 6 . 04 . 4 3 4 . 52 56 22 c 1 8 P A Y S T K C A K 6 6 1 1 8 7 2 4 0 0 8D 126 1 21 1 1 0 2 7 N 1 3 . 7 1 0 . 1 9 . 9 2 . 1 9 8 0 51 23 C 19HAMILTQN 0 8 5 1 8 5 2 6 0 0 40 3 8 1 1 1 9 7 . 6 3 . 6 6 . 0 7 8 9 15 24 C 2 0 H G M b S T A K c 6 o Q O U J U U U 3 D 148 1 1 1 1 3 5 4 5 E 8 3 . 3 . 5 7 5 9 70 25 C 21HP YMED1UM6 8o18 730 GO 2D 13 1 1 1 2 0 2 5 W 1 6 6 . 8 . 5 7 0 . 3 0 7 06 26 C 2 2 S A P P +CHAM6901905306 10 41 4 1 . 0 . 8 0 4 8 04 27 c 23V AND H 69il85 .34Gu 20 13 21 l 2 1 2 0 1 3 23b / 2 . 9 .1oo.063 . 46 t>0 55 2 a C 2 4 S A I G H E L U K 6 9 1 1 8 5 3 4 G 0 40 150 1 1 1 0 1 0 3 5 E 5 2 . 4 . 5 4 3 5 ' 4 U 29 C 2 5 G U R U N A T I N 6 9 3 1 8 5 3 6 5 U 10 2 1 1 23 0 9 0 6 5 N 3 8 G . 2 0 . 0 15 3C C 26GGLURAD0 6 9 ^ 1 8 5 4 3 0 0 3D 2 7 1 1 1 5 7 . 70 31 C 2 7 M Y R T L E ( A ) 7 0 i l 7 8 33GO 50 83 2 i 1 2 1 0 4 0 3 7 E 5 7 . 2 1 . 0 7 1 . 8 2 66 32 C 28CUB / 3417+63UU l O 9 1 1 1 G Q G 5 0 S 5 0 . G 1 . 9 6 1 . 7 3 33 "3 "3 ~s -* C 2 9 G K A P + R 6 6 G 7 3 6 i 7 4 / 0 5 0 ZD 10 1 i 1 0 6 5 / 0 6 2 5 6 . 1 1 . 7 Oo 34 c 3 0 L I T I L L T I M7361(La7 5 0 i u D 160 1 1 1 0 6 5 o 0 S l o 6 . 1 0 . 9 2 . 8 6 . 0 0 6 5 68 3 5 c 3 1 6 O N D H D L 0 R / 4 5 1 7 4 6 o 3 U t l ) 72 1 1 0 6 5 5 8 S 2 0 1 . 6 . 7 5 04 3 6 c 3 2 B E L L N G t . 2 6 7 5 1 6 5 4 5 0 0 ID 5 1 1 12 0 6 5 3 0 N 4 0 . 0 . 5 0 0 40 27 c 3 3 K E P U B L i G 6 7 3 1 6 4 4 5 6 0 60 2 4 2 i 31 12 0 8 G 3 0 N 5 5 . 0 . 0 5 3 . 0.35. 4 3 9 0 52 3a c 34SLGCAiM6GD6 /81b3450G ID 1 1 1 0 4 0 2 5 N 1 5 0 . . 5 0 0 9b 3 9 c 33GLU6 68ii624i60 10 5 1 I 1 2 0 3 5 3 0 W 5 4 . 0 . 4 0 0 u 04 4C c 36GLJV. IK i N b o 7 9 1 4 0 3 50 0 20 40 1 1 1 7 2 5 8 E 9 . 0 6 . 0 9 1 0 . 7 G 6 3b 4 I c 3 7 P 0 R f H 0 P E 5 8 4 1 4 2 5 7 5 0 2 0 15 1 1 1 7 6 . 0 . 7 2 7 37 42 c 38GR I P P L E S i 6 8 7 1 4 7 3 3 5 0 2D 11 i 1 1 9 . 5 . 0 9 1 04 4 3 c 39MORN 6 r . A R o 9 i i 4 0 3 5 G 0 2 0 27 1 3241 3 2 1 1 5 0 6 0 W 4 . 5 o 2 . 2 4 l . 8 3 1 . 6 8 0 49 • 4 4 c 40DAY TUN 6 9 5 1 3 3 3 4 0 0 4 0 26 21 1 1 6 0 3 5 6 2 2 . 1 7 . 8 0 1 4 . 0 . 1 6 6 35 45 c 41T AMAKAuR 7061504500 t o 1 1 / 21 1 2 1 0 9 O 3 0 6 1 O 1 . 7 . 9 9 07 46 c 42ALMA{0 T T ) 7 0 7 1 5 95450 ID 2 1 1 1 0 9 0 2 8 6 8 6 . 0 1 . 5 0 2 . 3 0 35 47 c 43GTTAWA 71215149UU47D 2 4 3 4 2 21 1 1 1 0 0 5 3 2 E 6 4 . 7 2 . 1 3 . 0 4 1 . 0 0 1 1 67 4 8 c 44ANNA ( 6K) 7 i 6 i . 5 0 4 9 G 0 i 3 D 195 21 1 1 0 1 0 3 5 E 1 5 0 . . 7 3 0 . 0 8 3 ' 1 . 2 4 6 4 49 c 4->LILY 8 . 7 3 ^ 1 4 1 5 0 3 0 3D 45 1 I 0 9 0 5 5 5 8 0 . 6 1 2 . 3 . 0 2 2 2 22 c 46ARL1 NUTUN 74U13 i 3 i u 0 l d D 156041 21 1 1 0 3 4 6 7 E 5 9 . 3 4 . 9 7 . 5 1 8 . 0 0 1 2 70 J 51 c 4 /SPbL .OL A l K / 4 5ibU5^30 20 293 1 l 1 1 034b/b28. 4 2 Z . 6 2 . 6 8 31 y 53 54 55 56 C 4 8 A L I G E S 7 4 9 1 3 2 6 0 0 0 ID 16 21 1 C 49BANKQ.FbNG735x40o250 ID 4 1 1 C 50rvJ0FRiGNG75914G6l5G 70 168 1 1 C 5 l 6 L C N P K N G b 7 6 2 i 3 8 6 i 5 0 l B D 1916 1 1 C 5 2 B L K P R I N G f c 7 b 5 i 4 0 6 4 5 0 1 2 D 1608 1 1 1 G 7 0 8 5 S 8 2 . 9 1 5 . 3 1 2 0 6 5 B 0 N 1 1 . 7 . 9 5 0 . 8 5 0 12 0 o 5 8 0 N 1 8 0 . 4 4 . 7 5 . 6 3 21 0 2 5 6 0 W 1 0 2 . 3 . 4 3 1 . 2 9 22 0 2 5 6 0 W 1 5 o . 4 . 3 . 3 70 62 29 62 22 5 7 58 59 fcC 61 62 C C c c c c 53HAMPTON / o 2 1 5 6 5 3 G 0 54EXCHANGE 7 0 0 1 2 0 5 3 0 0 55 SMERALOA 7 0 b l 1 3 5 3 0 0 5 6 E V E N S T A K 6 7 1 3 1 1 9 5 6 0 0 5 /GALUMET 7 2 3 1 1 6 6 7 0 0 58HUWARU F R 7 4 2 1 1 1 6 7 0 0 8 0 l u O 1 L l 1 4 U 6 0 S 4 8 / . 1 . 9 7 1 . 0 0 30 18 1 1 8 7 . 7 . 5 5 6 ID 3 2 0 2 . 5 . 1 6 1 1 . 3 50 95 1 1 1 5 0 5 5 E 3 6 3 . 1 . 2 5 IA 1 1 22 1 0 6 G 6 0 N 8 . 0 0 1 2 . 0 60 212 1 1 1 2 0 9 0 1 2 N 2 9 . 8 . 1 6 2 0 4U 40 30 41 15 50 63 C 59MbTbUK 7451197GG0ZUD 2878 64 C 6 G M A R + M A K Y 7 8 4 l G 9 6 1 0 G 20 48 65 C 61HGPE I M U . 2 701O6G4700 4A 5271 66 C 62GHAPLbAU 71o0925/u0 oD 32b 67 C 6 3 S K Y L A R K + R 7 1 8 0 9 6 6 5 0 0 .1 0 3 68 C 64K1LO 7 2 6 0 6 9 5 0 0 0 60 2357 1 3 1 2 1 1 0 3 3 5 N 5 2 . 4 . 0 3 3 . 0 3 4 . .1450 4 . 5 4 . 8 4 5 2 324 1 2 l 0 3 0 5 0 W 4 . 5 o 5 . 0 2 1 4 . 3 i 24 21 2 i l i O 2 7 N 4 0 . 4 2 . 9 0 0 i 1 3 1 1 1 0 2 7 N 1 I 1 . 1 . 3 3 3 1 1 1 1 4 5 3 5 N . 3 6 9 . 0 u 2 . 0 0 1 . 4 0 4 7 ' o7 40 59 41 84 39 69 70 71 72 72 74 C 65G0L0STHM C 6 6 0 U P L c X - J N C 6 7CRUSADbR C 680KU F IND C 69ALP1NE C 70JOYCE 737093513O ID 40 1 12 739J.0G5800 2D 10 1 1 7 5 3 0 8 2 6 1 5 0 ID 6 1 1 8 i 7 0 3 3 6 8 G 0 i D 18 1 1 8 2 1 0 3 9 7 1 5 0 1 1 0 17099 1 1 6 8 5 1 9 0 2 8 0 0 ID 10 1 1, 21 1 1 G / 3 2 0 N . 5 7 5 0 . 5 5 1 3 5 3 5 N 6 4 . 3 . 0 5 5 . 8 0 0 0 6 5 . 7 1 . 1 6 b 0 1 5 6 5 E 7 . 7 5 1 . 3 1 3 . 0 8 0 . 5 0 0 7 5 2 O N . 4 1 1 . 3 1 7 . 1 1 1 . 6 5 2 0 I 2 0 2 5 W 3 G . 5 . 1 9 5 . 1 0 . 2 0 0 36 4 7 39 40 48 6 7 7 6 77 78 79 8 C C 71B + R uRUUP C 72ELK C 73 BARNET T 7 6 3 1 3 1 6 1 5 0 i A 3 1 3 7 4 4 1 2 6 7 0 0 U ID 2 1 3 1 4 G 9 6 o 2 G u ID 2 1 1 3 106545N 1 . 0 1 1 1 5 3 G S 1 G . G 1 0 2 0 1 4 W 3 . 5 1 . 0 ,2 ),02 16 32 39 SLUGAN C I T Y DATA DECK - CARD TWO 81 C 117U85b4i • 1 6 ' 4 82 C 2 2 . 1 3 6 83 C 3G77oOW3l2 1 4 . 1 4 4 3 5 3 6 84 C 403065W4 3 2 3 . 1 4 5 4 85 c 5 6 . 1 3 6 5 86 C C t i 5 0 O 5 W 5 8 . 1 3 5 5 87 C 7 0 7 0 8 4 S 4 1 1 3 . i i 2 6 5 4 4 2 43 43 88 C 8 0 4 0 7 5 E 4 1 b . l 4 2 3 3 4 89 C 9G5G50E31 3 3 1 3 . 1 1 37 3 4 4 3 4 2 5 5 66 b 7 SC C 1 0 0 5 0 8 9 3 3 1 2 3 . 1 1 4 3 3 3 3 2 5 6 5457 67 91 c 11 3 i 1 2 . 1 3 3 3 5 92 c i 2 0 0 0 8 5 b l 31 2 5 1 2 . 11 3 6 4 4 4 3 4 2 6 5 55 6 9 2 C 131607 Ob 522 i 5 4 3 0 . 1 1 45 2 3 3 4 1 3 3 2 4 5 465 / 4 94 C 1403CD5E1 31 2 5 1 5 . 1 3 2 6 3 4 c c J —' C 15 5 . i 5 5 4 5 96 C i o 1 7 0 4 0 b 4 i 1 i . 1 4 5 3 5 4 97 C 17 1 3 . 1 4 4 3 4 5 98 c 18 51 1 2 5 3 8 . 1 4 1 1 5 6 99 C 19 4 1 3 . 1 ' 4 6 3 6 3 ICC C 2017 38UW4 1 4 2 . 1 6 1 2 6 5 4 o 101 C 21 22 1 3 3 . 1 5 6 4 5 3 1C2 C 22 1C3 C 2 3 0 4 u o 3 w 4 I 2 54 6 . 1 1 4b 5 3 4 2 64 43 1C4 C 2414U4 0W31 3 2 6 . 1 1 644 34264 63 6 1C5 c 2 5 0 4 2 u 6 E 3 3 1 1 8 . 1 1 38 5 8 4 4 2 3 o 2 4 5 46 67 b o 1C6 C 26 4 0 . 1 4 3 1 4 1 C 7 C 2 /OG3.55E22 1 8 . 1 2 5 5 6 6 o ICS c 2 8 1 1 0 5 2 N 4 1 2 1 0 . 1 4 4 4 4 1C9 C 2 9 1 1 0 5 2 N 4 1 2 9.1 3 4 o 6 4 o 5 5 11C C 3 0 0 1 0 5 8 E 4 1 2 2 3 . 1 1 4 6 3 6 4 3 1 2 6 1 5 2 54 55 J 111 c 3 1 0 2 0 3 1 E 5 1 i / . i i 26 5 3 4 4 2 2 62 63 67 6 0 ( 112 C 32 3.1 1 22 2. i 4 5 6 6 6 O 113 C 3 3 0 1 0 6 0 E 3 1 1 22 3 . 1 4 5 6 6 o 1 14 C 340 7575S32 2 i 3 i 7 . 1 1 4 a 36 544 3226 5 53 5666 115 C 3 5 1 2 6 9 0 N 4 1 3 8.1 6 3 5 s, 116 C 3 6 0 5 5 / 0 5 3 1 2 i 1 4 . 1 1 34 5 6 4 3 3 2 o5 J ? 117 C 3 7 8 .1 b o 3 3 5 n e C 38 3 .1 b 4 6 119 C 3902050W31 1 5 . 1 4 2 3 4 2 6 12 C C 4 0 1 4 3 5 8 E 4 2 3 1 6 . 1 5 4 4 6 121 C 41 16083632 1 1 4 . 1 1 2838 455 36245 34 4 756 122 C 4 2 G 8 5 9 0 S 2 2 1 9 . 2 2 5 5 4 123 C 4 3 i 6 0 6 0 ^ 5 1 320.114826 3 8 4 3 4 3 3 2 4 5 44 4 / 3 6 124 C 44 i 2 2 . 1 5 5 3 4 1 6 5 4 6 6 125 c 4 5 0 9 0 4 2 N 4 1 3 2 9 . 1 1 1 4 4 3 6 2 4 5 56 126 C 4 6 0 5 G 5 0 E 2 i 3 i 4 4 3 8 . 1 1 39 2 9 3 4 1 3 5 2 6 7 566 5 68 6 127 C 4 7 0 3 6 7 4 c 2 1 2 2 0 . 1 3 2 3 5 5 6 6 128 c 4 8 0 3 3 4 5 E 2 2 1 2 0 . 1 1 36 2 8 2 5 4 3 4 2 5 4 b 6 6 7 6 7 56-129 c 491608Ub42 1 11.11 26 63o 56254 64 5 13C C 5 0 0 6 0 8 0 S 4 3 1 4 8 . 1 1 26 1 4 1 3 4 2 6 3 45 6 131 G 5106 5 8 9 3 2 1 5 3 1 7 . 1 1 38 2 8 4 4 2 3 5 2 6667 6 5 132 C 52G6073N44 1 2 i . i l 29 3 9 2 6 3 3 5 2 445 8695 7 1^3 C 5 3 0 4 5 6 6 E 3 5 1 2 2 . 1 1 26 3 322 44 55 134 c 54 1 6 . 1 6 6 2 5 5 125 c 53 136 c 5o 1 4 . 1 4 2 5 5 137 C 57 42 2 6.1 3 4 4 4 128 C 5 3 0 6 0 8 9 N 4 i 2 4 . 1 1 o 5 b _>424o 64 6b 4 139 C 59170o2v»2132 3 2 1 2 . 1 1 2 9 49 5 4 4 3 3 2 5 8 4 7 4 6 4 5 6 140 C 80 141 C u i 1 5 0 6 5 ^ 3 2 i 5 5 . 4 1 1 / 3 / 4 4 1 3 4 2 2265 66 142 C 6203560W32 1 4 5 . 1 1 J o 3 4 5 3 4 2 6 4 6 3 6 3 6 6 6 143 c 6312 5 80N52 1 4 .1 4 3 144 c 64100/4651 2 1 2 . i 4 4 3 5 145 c 6 5 0 5 0 7 5 3 2 1 2 21 6 . i t 5 0 6352 6 3 6 4 6 5 146 c 66000/5^41 4. i 4 4 5 14 7 c 6 7 / . i 3 5 6 6 148 c 68G70uOS31 9 . 1 4 5 3 149 c 69 7 . 1 3 3 6 3 15C c 7 0 0 3 0 8 0 E i i 5 i 2 1 3 . 1 1 4 4 4 3 3 2 5365 151 c 71 b . i 4 4 152 c 72 41 6 , 1 3 6 153 c 7 3 0 6 0 7 0 3 4 1 8 7.1 2 4 5 6 EKC CF F I L E > 

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