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The geology of the Rocky Mountains Riley, Christopher 1929

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THE GEOLOGY OF THE ROCKY MOUNTAINS — by — CHRISTOPHER RILEY A Thesis submitted for the Degree of MASTER OF ARTS In the Department of GEOLOGY The University of British Columbia C O N T E N T S Page* INTRODUCTION 1. CHAPTER 1 GENERAL DESCRIPTION OP THE CORDILLERA OF NORTH AMERICA General Statement General Description of Topographic Units Coast Ranges The Pacific Coast Downfold Belt of High Uonntains Area of Plateaus and Mountain Masses 1* The Colorado Plateaus 15 The United States Rockies 16 The Endicott Mountains 16 The Mackenzie Range 17 Eastern Cordillera in Canada 18 CHAPTER II THE TOPOGRAPHY AND PHYSIOGRAPHY OF THE ROCKY MOUNTAINS General Features 20. Ranges of the Rocky Mountains 25. Drainage 29. Lakes S3. Glaciers 33. Parks 34. -3-CHAPTER III GENERAL GEOLOGY Pagi Introduction 35. Representative Tables of Formations 36. Descriptive of Formations 42. Beltian and Pre-Cambrian 42. 49th Parallel 43. The Lewis Series 43. The Galton Series 47. Bam Creek 52. Windermere 54. C.P.R. Hain Line 55. Robaon Peak §6. Cambrian 57. North Kootenay Pass 56. Flathead 58. Elko 59. Ram Creek 60. Windermere 61. C.P.R. Main Line 62. Robson Peak 67. Finlay River 69. Ordivician 69. Windermere 70 C.P .R.Main Line 71. Robson Peak 72. Silurian 73. Windermere 73 C.P.R. Main Line 73. Devonian 74. Galten Range 75. MacDonald Range 75. Crewsnest 76. Elke 77. C.P.R. Main Line 77. Roche Miette 79. Carboniferous 79. Flathead 79. C.P.R. Main Line 80. Roche Miette 81. Permian 81. Triassio 82. Flathead 83. Banff 83. Roche Miette 84. Jurassic 84. -3-Page. Crowsnest 85 Banff B6 Roche Miette 66 Cretaceous 86 Crowsnest 88 Banff 91 Northern Areas 92 Tertiary 92 Flathead 92 Pleistocene and Recent 93 Igneous Rocks 94 Parcel! Lavas 94 Crowsnest Volcanics 95 Jurassic Tuffs 97 Ice River Intrusive 98 Cross River Intrusive 99 Bull River Intrusive 99 CHAPTER IV THE STRUCTURE OF THE ROCKY MOUNTAINS Introduction 100. Structure of the Southernmost Rockies 101. Western Area 102. Central Area 102. Eastern Area 102. The Lewis Overthrust 103. General History of the Structure 104. Structure in the C.P.R. Section 105. Eastern Section 105. Central Section 106. Western Area 107. Summary of Structure of C.P.R. Section 107. Structure in the Yellowhead Pass 108. Structure in the Peace River Area 109. Structure in the Liard River Area 110. Structure of the Rocky Mountain Trench 110. -4-CHAPTER V HISTORICAL GEOLOGY Page. Depositions! History 114 Beltian 115 Paleozoic 115 Mesozoic 117 Structural HiBtory 118 History of Drainage 120 Glacial History 122 BIBLIOGRAPHY LIST OF KAPS. PLATES AND CORRELATION T BLB. In Pocket. Structure Section across the Rocky Mountains on the C.P.R. main line from Columbia valley to Cascade trough. Panoramic Map of the Canadian Pacific Rockies. Map of the Canadian Rockies. Triangle Tour of B.C. Plate I. Map Illustrating Nomenclature of the fountains of Western Canada 4. Plate II. Physiographic Regions of the Cordillera of the United States 5. Physiographic Regions of Mexico. 5. Plate III.View over Coast Range near Kleena Kleene 11. View over Interior Plateaus . 11. Plate IV. Takakkaw Falls 28. Lake Minnewanka, nerr Banff. 28. Plate V. Bow River valley at Banff. 29. Mora&ne Lake and the Ten Peaks 29. Plate VI. Moraine Lake 31. Lake McArthur 31. Plate VII.Emerald Lake 32. PI.--' - g^xe o'Hara 32. Plate VIII Development of Rocky Mountain structure 104. Plate IX. Sections Across the Beav^rfoot and Brlsco Ranges 106. Map showing location of sections 41. Correlation Table 99. INTRODUCTION A paper on the geology of so large an area as that occupied by the Rocky mountains will necessarily be somewhat in the nature of a written reconnaissance. Though the subject may suffer from the lack of detailed treatment, yet there is considerable value in grouping the known geological facts of a system as a whole. Such is the aim of this paper. Considerable geological work has been done in the Rocky mountains, but the great majority of it has been confined to the areas contiguous to the mai n line of the Canadian Pacific Railway and south to the 49th parallel. Enough has been done throughout the area to afford a general idea of the geology of the entire system. Vast areas, however, are still unexplored by the geologist and a very attractive field of study offers itself in these mountains. It is attractive because of the many problems there that still await solution, because the comparatively little deformed strata and their generally conformable nature should render the solution not too difficult, because it is almost a virgin field of study and because of the richness of the fossil record. The writer wishes here to express his appreciation for helpful criticism, advice and time given by Dr. Schofield during the preparation of this thesis. CHAPTER I. GENERAL DESCRIPTION OF CORDILLERA OF NORTH AMERICA The Reeky Meuntains, farming as they de, only a unit of the great mountain system of western North America, can be best discussed after the general physiography of that system is outlined and the relationship of the part to the whole is made clear. Hence, before beginning a detailed description of the Rockies themselves, the geography and geology of the entire Cordillera will be briefly outlined. That no definite nomenclature has been accepted for this great System is evidenced by the fact that as many as twenty-six different names are recorded in the literature and on maps, in some cases the name of Rocky Mountains being 1 given to the entire area. The admirable suggestion of Daly that the name be the Cordillera of North America will be followed in this paper. The Cordillera forms one of the grandest mountain systems on the globe, covering an area of over 2,300,000 square miles. By way of contrast it might be stated that the area of the Andes is about 1,000,000 square miles, the Himalayas 300,000 square miles, and the Alps 70,000 square miles. The Cordillera of North America stretches from Alaska in the north to Central America in the south and 2 east to west from the Great Plains to the Pacific. 1. Daly,R.A. Geol.Surv.Can.Mem.38. 1912. P.18 2. Idem P.17 -8-This vast sea of mountains is neither structurally no? physiographically one unit, but on the contrary 8ho.?s a great complexity in these characteristics. It has,however, two great general structural zones kno-?n as the Eastern and Eastern Géosynclinal Belts, having as a general dividing line a narrow area roughly parallel to the summits of the Canadian Selkirks. Eastward to the Plains sedimentary forms are dominant and almost entirely included in one huge structure called the Rocky Mountain Géosynclinal Prism. This reaches from Alaska to Arizona. Paralleling this and west of the Columbia lies the Western Géosynclinal consisting mainly of 1 sediments of post Mir.sisslpian age. The Cordillera may be conveniently divided into a 2 number of topographic units. These are: 1. The Coast Ranges including the Queen Charlotte Islands, Vancouver Island, the Olympics of Washington, the Coast Ranges of Oregon, the Coast Ranges of California and the axis of the Californian Peninsula. 2. The Great Pacific Trough formed by Hecate strait, Georgia Strait, Paget Sound, the Cowlitz and Williamette valleys in Washington and Oregon, the Great Valley of California and the Gulf of California. 3. Belt of high mountains...*...which includes the Coast Range of British Columbia, the Cascades of Washington and Oregon, the Sierra Bevadas, the San Gabriel and San Bernard-ino ranges of California and the sierra Maire Occidental of Mexica. 1. Sehofield,S.J. Gaol.surv.Can. Guide Book Ko.9.1913. p.20 2. Jonaa and Bryan, Rorth america, 1924. p.136 -9-4. A great area of plateau, and irregular mountain masses... mad* up of the interior plateaus of Alaska, Yukon and British Columbia, the Columbia and Colorado Plateaus, the Groat Basin and Range provinces of the United states and the Northern Basin of Mexico. 5. The Rocky Mountains of Canada and the United States. A few general features characterise the entire 1 system: 1. A continuity of the main physiographic features. 2. A decreasing width northward of the Cordillera. 3. Decreasing height northward. 4. The extraordinarily continuous trough-like water valleys whose trend is almost north-westerly. General Description of Topographic Units The Coast Ranges. The Coast Ranges occupy the western borderland of the United States. In Canada they are located west of the main land and form Vancouver Island and Queen charlotte Islands. In British Columbia they form one structural unit and are known as the Insular system, of which the Queen Charlotte Islands form the northern range. This range,which o trend* 38.28 y, is about 180 miles long and averages twenty milea in width. It is separated from the mainland by the submerged porthem part of the Pacific Coast Downfold called hare Hecate strait. 1. Jonas and Bryan, North jmerica. p.492. GBOGRAPmC BOARD OF CANADA MAP NOMENCLATURE M O U N T A I N S W E S T E R N C A N A D A T!ON BKLlH ^YSTiM^. MUUH'M).^  ¿6 ^UtUtJH, AMR M^ /ÎHiAPS AH'^AKÌ^! MM%ti rA^n.&.J^  r J^'nA -5 The Queen Charlotte Island range, In the main, is made up oi resistant metamorphic and crystalline rocks. It is ragged with steep glaciated slopes with rounded, rarely serrated summits which vary from 3,000-6,000 feet in height. In the northern part of the range are lew areas underlaid by sediments and volcanics generally less resistant than the older rocks. The largest of these low areas forms the north 1 oast section of graham Island. The Vancouver Range constitutes the whole of o Vancouver Island, trending E.55 The island is 290 miles long aad 50 to 80 miles broad* Its insular nature is due to the Pacific Coast Downfold to the east and a smaller tramrerse o downfold to the south which strikes B.70 and is now occupied by the Strait of Juan de puea. The elevation of the moamtains of the island is about 1,800 feet near the southern aoaat. This increases rapidly northward, where in many parts It reaches 4+000 feet with eld residuals attaining an eleva-tion of 5,000 and 7+000 feet. The materials are deformed, metamorphic, volcanic and sedimentary rocks intruded and replaced by many irregulr^ bodies of granitic rocks and fringed along both coasts with fragmaatal sediments resting unconformably on metamorphic and 2 granitic rocks. The Olympic range of Washington is still very imper-fectly known due to the density of its forests. The Oregon mountains consist of Cretaceous and Tertiary beds which have 1* Clappt C.H. Seal.surv.Can. sum.Rep. 1912. 0.17 8. Idem. Idem. Guide Book.Ro.6.1%111. p.200 Plate II, n ^ + ^ Sfaphic Regions of the Cordillera of the United btates. ( After Blackwelder). Physiographic Regions of Mexico, ( After Jones and Bryan) + -6-been anly moderately folded. The Olympics rise to a height of 8+009 feet. The Oregon mountains are lower and less continuons. These ranges are crossed successively by thé 1 Chanalia. Columbia and Umpqua rivers. Extending between the Coast Ranges of Washington and Oregon and those of California is a small transverse range .. the Xlamatha. Its materials are granites intruded into 2 Devonian. Carboniferous and later rocks. South of the Klamaths the Coast Range is again continued in California. similar to the ranges in the north, the relief is not great, being on an average from 3,JOO to 4,000 feet with isolated peaks reaching 6,000 feet. They expose Cretaceous and mare recent rocks, lava flaws and igneous intrusives, the whole broadly deformed and dissected. The most important agent in the present general relief hag been block faulting* The western edge of the dissected block on which the Coast Ranges are developed is a submarine line 600 feet deep. West of this, the surface falls 8,000 feet or more into the pacific abyss. The eastern edge over-looks the 6ret Valley 50 to 100 miles from the coast. Between these majer scarps are a number of longitudinal valleys outlined in parallel faults and set somewhat oblique to fha coast line so that the extremities of the ridges reach the *$*at in bald promontories and the ends of the valleys in low bays. The southernmost part of the Coast Ranges is formed by the Sierra Madre Mountains and the Mountains of Lower 1. Blaakweldar, E. Gsol.u.S.A. p.191 2. Diller, J.S^S.S.S.S. Bull.102. -7-California. V.hile not continuous with the Coast Range of California, they are similar in materials and history. The Pacific Coast Dowifold Like the Coast ranges, the Pacific Coast Downfold preserves its north-south trend with few interruptions, the greatest being the Klamath Mountains. North of this range,it consists of Hecate Strait,the Strait of Georgia,Puget Sound, and the Cowlitz and '..illiamette Valleys. It is continued southward by the Great Valley of California, of which the structure deserves pome comment. Prior to the Pliocene,this valley was already existent, but the thrusting and folding of the ranges to the east and west of It during that period accentuated the depression by a sharp closing in. Since that time there has been a continuous deposition of fluviatile and sub-aerial sediments of alternating sand,gravel,clay and loess until the large area of 400 miles long and 50 miles wide has 1 been filled 1,000 feet or more. Completing the long Pacific depression is the 'hilf of California with the Sonoran Desert to its east. Belt of ^igh Mountains *** Included by Spencer in the Belt of High Mountains are the Kuskokwin Mountains, the Alaskan Range, the Kenai Mountains, the St.Elias Ran??e and the Nutnotin Mountains all of Alaska. Stated briefly,this writer's opinion is that the uniform summits found over the greater portion of the Pacific IT Drake, N.F. JouiTof Geology.Vol.5. 1897. p.573 2. Spencer, A.C. Geol.3oc.Am. Vol.14.1903. p.118 -8-Mountain System In the north are representatives of elevated peneplains which have suffered deep dissection. He arrives at this conclusion mainly because the peneplains of the different portions of the coastal mountains and the inland plateaus can be correlated with one another. The Pacific Province was raised, after the production of the peneplain by erosion extending through Eocene time, mainly by uplifts of a continental character. Regional elevation, which was accom-panied by warping, flexure or displacement, elevated tectonic blocks which have not been effaced by subsequent erosion. Tangential compression has not been the cause of this mountain building. The most southerly portion of the laskan coast ranges is the low range in the Alexander Archipelago. North-ward is the St.Elias Range, the southern end of which is over-lapped by the Coast Range of British Columbia to the east just before that range merges into the plateaus of the interior. The St.Elias Range averages 150 miles wide and beyond its culminating peaks divides into tw ranges, the skolai and the Chugash. Skolai on the east continues to the vicinity of Mount #rangell. North-east of this volcano lies the Nutzotin range which also has a north-west trend. The tlaskan range overlaps the Butzotins which continue north-west as far as Mount Kimball where their axis assumes a westerly direction as far as Mount McKinley, the highest mountain of North jmerica. Here the range turns south westerly gradually diminishing in height towards Cook Inlet. Occupying the Alaskan Peninsula is the Aleutian Range and to the north is the little known Kuskokwin Mountains. The Coast Range of British Columbia is a deeply dissected granitic ridge 50 to 100 miles wide and 1,000 miles long, rising from the sea with few intervening plateaus to 4,000-6,000 feet and increasing to 7,000-8,000 feet in the axis of the range. The height as a rule is uniform with few outstanding summits. Deep,ice-worn, steep-sided valleys penetrating the range in all directions are one of its characteristic features. A fiord system is well developed along the coast with fiords penetrating the range to a depth often exceeding 100 miles. This range is essentially a complex batholith of late Jurassic or early Cretaceous age cutting, enclosing and flanking masses of Paleozoic and earlier 1 Mesozoic strata. In the same general topographic area as the Coast Range of British Colombia, though not a continuation either physically or geologically, are tho Cascades of ^ashin^-ton and Oregon. Two subdivisions exist, the dividing line being in the general vicinity of Mt.Rainier. Both north and south divisions are uplifted masses of peneplained, metamorphosed Paleozoica. The main deformation aid uplift took place in Tertiary times* <Vith the uplift, north and south .^arpings gave rise to three rangas and two intermediate valleys. In relief, the Cascades consist of a 75 mile wide, dissected, rather flat-topped range with somewhat accordant altitudes of about 5j,000 feet. Extending north and south rather toward 1. McConnell, R.G. Geoi.Surv.Can. Guide Book Ko.10. p.6 -10-the eastern side of the Cascades are numerous volcanic cones rising 5,000 to 4,000 feet above the general level of the range. The main feature of this belt of high mountains in California is formed by the great sierra Bevadas. Their continuation in northern California is known as the Cascade and Lava Sheet Mountains, while in the south they branch into 1 the San Gabriel and San Bernardino ranges. The Sierra Eevadas are composed of a complex series of rocks of .any ages which have been close folded, metamorphosed, subjected to repeated volcanism and peneplained. They were folded at the close of the Paleozoic with mucn igneous intrusion. At the close of the Jurassic they were compressed, folded and up-lifted with batholithic intrusions and much metamorphosed. During the Cretaceous and Tertiary, peneplanatlon occurred, and at the end of the Tertiary a great uplift with much faulting and shearing, accompanied by wide lava flows took place. The main crest of this rugged range varies between 6,000 and 13,000 feet with a maximum height in one peak of 18,000 feet. In Mexico, the Sierra Madre Occidental continues the province aouth ard. Coming first into evidence at the international boundary, this range extends south t^ the Rio Grande de Santiago, where it adjoins the volcanic plexus of Southern Mexico. its history is nome?hat linked up with 1. Drake, N.?. Jour.of Geology. Vol.5. 1897. p.573 -li-the central table land of Mexico, but it suffered greater uplift and a more general volcanism. A narrow, deeply dissected tableland forms the highest mountain belt and is almost smothered in the igneous flows which accompanied its 1 uplift* Area of Plateaus and Mountain Masses The province of plateaus is represented in Alaska by the Interior Plateau* This is a broad Arctic slope lying between the Pacific Mountain system and the North Easterly Mountain Ranges. Though the relief is considerable the elevations are less than the bordering ranges and are 2 often rounded and of an accordant summit level. In the Yukon territory the Plateau system is a continuation of the Alaskan with a general width of 260 to 300 miles. In the main it consists of a folded basement of Cretaceous limestone cut by quartz monzonite or granite upon which rests a great thickness of Tertiary lavas. A mountainous area in northern British Columbia forms a generai division between the interior plateaus of Yukon and British Columbia. The plateau region of the latter province has a general elevation of 3,000 to 4,000 feet and is formed of a succession of plateau surfaces, some of great extent but broken by deeply cut valleys of a drainage system whose main channels lie 1,^00 feet or more 1. Jones and Bryan, North\jnerica. p.428. 2. Idem. p*510. View over th^ Coast Range from a of the Kleena Kleene river. ioint on the UBC Scanned by UBC Library View over the Interior Plateaus from the same UBC Scanned by UBC Library South point as Piote III. -12-below the remnants of the upland surface. ¿long its western border, the plateau region in places directly adjoins the Coast Range, but in others is separated from it by high, rugged mountain ranges such as tne Cascade Mountains of southern British Columbia, which in turn are separated from the Coast Range by the deeply intrenched Fraser Valley, long its eastern side the plateau region is bordered by a series of mountains divided into mountain groups by long, deep valleys trending north-westward and northward, and separated from the Rockies by the Rocky fountain Trench. Toward the south the eastern bordering mountain assemblage broadens to include the exceedingly ragged Selkirk Range, whose higher summits rise to elevations of 11,000 feet and more, and finally in the vicinity of the International Boundary the interior plateau surface is reduced to a comparatively narrow width by the encroaching mountain groups on both sides. 1 In respect of geologic structure Ransome says: "It is impossible in the present sta^e of knowledge to make any satisfactory generalization of the geologic structure of the Interior Plateaus of Canada and Alaska." In general, the structure is complex and. much work remains to be done before the number, age and relative importance of deformational epochs can he known. The moat marked effects are those referable to late Mesozoic time. Although part of the 1. Ransome, F.L. Problems of American Geology, 1913. p.336 -13-intermontane region of Canada was covered by Cretaceous deposits, geologic descriptions of that area as a rule fail to present clear evidence of deformation due to the Laramide revolution. Most workers, however, seem to agree that the g e n e r a l plateau character of this surface dates in part at least from early Tertiary time, and the fact that much of the area from the International Boundary north to tne 55th parallel is covered by nearly horizontal lavas of mid-Tertiary age indicates that the belt of interior plateaus 1 has been a fairly rigid mass throughout the Tertiary. Continuing the Interior Plateau area south of the 49th parallel is the Columbia plateau. It lies between the Cascades to the west and the Bitter Root Mountains on the east, and to the south is bounded by the extension of fault block ranges from Nevada. It consists essentially of great Tertiary lava flows of an intermittent nature which reach thicknesses up to 4,000 feet. These lavas buried a rugged topography as is shown in some of the deeper canyons and by the fact that the Blue Mountains of eastern Oregon rise like a a great island above the general lava level. After the flows came the rise of the Cascades with minor warpings of the plateau itself. South of the Columbi Plateau is the Great Basin and Range Province. Its area is roughly 800 miles north and south and 500 miles east and west, and includes all Nevada, 1. Ranaome, F.L. Problems of American Geology. 1913. p.336 2. Idem p.339 -14-moat of Utah, and much of Arizona and New Mexico. It is formed of a large number of isolated north and south trending ranges, most of which, tilted and block faulted, are masses of previously folded and peneplained sedimentarles, some real d e s e r t s and the Great Basin of Nevada and Utah. The origin of the Basin and Desert Ranges is generally regarded as due mainly to extensive and vigorous deflation on a region that had been previously flexed and profoundly faulted and then planed off, bringing narrow belts of resistant rocks into juxtaposition with broad belts of weak rocks, the former now forming the desert highlands and the latter the desert low-1 lands and interment plains. The Mexican Plateau occupies a great part of Central Mexico, and lies between the Slerrn Madre Occidentals and Orientals. It stretches from the United states boundary almost the entire length of the country. Its structure is summed up by Suess in the statement that "it is a broken, folded land of much the same type as the Basin Ranges." There iB no real orographic boundary between the provinces of United States and Mexico, though the beds entering into the structure of the Great Basin Ranges are Jurassic or older, whereas the beds of the Mexican Plateau are chiefly Cretaceous with the Paleozoics unrepresented. The geology of all Mexico is much alike in that the area was submerged entirely during the Cretaceous, emerging at the close of the 1. Gilbert, G.K. U.S.G.S. Prof.Paper 153. 1928. p.7. -15-period. This uplift was accompanied by much north and south close folding and faulting. It was worn to a peneplain in early Tertiary times. The raising and tilting of this peneplain with accompanying extensive volcanism makes the present Mexico. 1 The Colorado Plateaus Included in the southern part of the united States Rockies is a series of wide uplands...the Colorado Plateaus. They lie between tho Great Plains to the east and the Basin Range Province to the west. On the south they merge into the Mexican Plateau, and to the north they terminate irregularly against several ranges of the Rockies. ¿heir general elevation is about 6,000 feet, and in some cases reaches 7,000, but they are notable for the continuous weight of wide areas. Their structural characteristics are the general horizontal nature of their sedimentary strata, and a great north and south series of faults, by which huge blocks of these still roughly horizontal strata have been at various periods elevated or depressed. Topographically, they con-sist of a great number of individual plateaus of varying elevations, bounded by deep canyons, fault scarps, and 2 erosion cliffs. R.T.Hill says* "An area of strata so extended, lifted so high without serious deformation since Algonkian time, is most remarkable. Yet but a short distance 1. Ransome, F.L. problems of American Geology, pp.331-334 2. Hill, R.T. quoted in Ransome, idem. pp.332-333 -16-both to the north and to the south in the Rocky Mountains and in the Mexican Plateau, we have examples of intense mountain folding and deformation." The United States Rockies The Rocky Mountain system of the United states north of the Colorado Plateaus is very complex and contains a large number of separate ranges. The rocks vary in age from pre-Cambrian to Tertiary and all varieties are represented. The area gives evidence to having been at different times subjec-ted to many forces indicated by intrusive masses, large and small, by volcanic flows, by profound faulting and overthrust-ing and by folding. The periods of deformation are confined chiefly to post Cretaceous times and eight periods are known. The geology is consequently very complex and does not permit of treatment in as short a space as is available in this paper. 1 The Kndicott Mountains The Kndicott Range of A l a s k a forms the most northerly range of the Cordillera. It extends in an almost east-west direction a cross Alaska. The mountains rise to a generally uniform elevation of 6,000 feet, suggesting a much dissected plateau. The northern slope descends abruptly to the edge of the gentle arctic slope and meets it at an elevation of about 2,500 feet. The rocks are mainly eHdiments of an age 1. Ransome, F.L. Problems of American Geology, 1913. p.336 -17-from Silurian to Upper Cretaceous. The folding is generally open except on the north side, where overturning and considerable faulting Occurs. The deformation seeas to be post-Cretaceous on the whole. 1 The Mackenzie Range South of the Endicottu and not included here in the British Columbia Rockies is the Mackenzie Range. It extends from the lowland between the Yukon and Porcupine Rivers in the north-west to the Liard River in the south, and attain a maximum width of 300 miles. Elevations vary from 2,800 to 8,000 feet. These mountains consist of crystalline metamorphic rocks probably pre-Cambrian to Cretaceous with comparatively small masses of intrusive rock. Their struc-ture is mostly of open folds though sometimes close and overthruat to the west. Eastern Cordillera in Canada "The Eastern division (of the Cordillera in Canada) consists from west to east of the Columbia, Selkirk and Rocky Mountain systems. The groat intermontane depressions which individualise the above ranges are the Selkirk depression, occupied by the south-flowing Columbia River, which separates the Columbia Range from the Selkirk Rcnge; the Purcell trench, occupied for the most part by Koetenay Lake, which subdivides the Selkirk system, and the Rocky Mountain trench, occupied in its southern, part by the south-flowing,Kootenai ^iver, and in its northern part by the Colu Dia river which flows northward and crosses the main line of the Canadian Pacific Railway at Golden. This trcnch 1. Ransome, F.L. Problems of American Geology, 1913. p.336 -18-"separatee the Selkirk system ir cm the Rocky Mountain system, tne most eastern mountain system of the Canadian Cordillera." 1 An important part of the Selkirk system is the 2 Purcell range. Schofield describes it as an elliptical-shaped group of mountains about 250 miles long by 60 miles wide, lying between the Rocky Mountain trench and the Purcell trench. Describing the topography of the Selkirks, 3 Schofield writes: "In a view from one of the higher peaks of tne Selkirk range, the moat striking feature is the series of almost unbroken ridges, having an approximate elevation of 7,000 feet. The ridges trend in all directions without relation to the underlying structure, and evidently represent the remnants of an uplifted and dissected peneplain. Numerous peaks having elevations of from 8,000 to 9,000 feet project above this old land surface, and great valleys have been carved to a depth of 6,000 feet below it." The rocks of the Selkirk system consist of pre-Cambrlan,Paleozoic and Mesozoic sediments intruded by great masses of granite. Sedimentation went on fairly continuous-ly from Beltlan times to Upper Jurassic times 3?hen the Jurasside revolution occurred. Peneplanation followed, but further uplift took place at the same time as the building 4 of the Rocky Mountains. 1. Schofield, 3.J. Geol.surv.Can. Memoir 117. 1920. p.7 2. Idem Memoir 76. 1915. p.8 3. Idem Memoir 117. 1920. p.61 4. Idem Royal soc.Can.,Trans.& Proc. 1923. p.92 -19-The Rooky Mountain system forms the most eastern belt of the Canadian Cordillera. As discussed in this paper, it stretches from the 49th parallel to the Liard River, and has an average width of 40 to 60 miles. It is made up of a series of ranges in north and south "en echelon" relationship to one another. The rocks are almost entirely sedimentary of ages from Beltian to Cretaceous. These have been almost continuously deposited. Uplift took place in the early Tertiary and both folding and faulting, thrust and normal, were involved in their uplift. UBC Scanned by UBC Library -20-CHAPTER II. THE TOPOGRAPHY AND PHYSIOGRAPHY )F THE ROCKY MOUNTAINS General Features The Rocky Mountains proper form the eastern part of the Cordillera from Yukon in the north to the Colorado Plateaus in the United states. In British Columbia and Alberta they extend from the International Boundary north soma 860 miles to the Liard River. They are bounded on the west by the Rooky Mountain trench, and on the east by the foothills. The system has an average -'idth of 50 miles between the 49th and 53rd parallels. Northward it diminishes to about 40 miles at the Peace river, decreasing still more to the Liard. The general trend of the system o ia north 35 ¿est, and the strike is roughly sub-parallel to the western side of the continent. It is made up of a number of parallel ranges and ridges which, in a general way, lie "en echelon," the more northerly segment being situated slightly west of the ono to the south. The ruggedness of the topography varies in different latitudes, and although tna highest point in the entire Rockies is found in Pike's Peak, which is 14,147 feet high, yet the most highly sculptered ridges and ranges occur between the Crowsnest pass and the Robson district. Here the summits attain an average height of about 10,000 feet. Robson Peak, the highest peak of the Canadian Rockies, has an elevation of 12,792 feet. A very definite western boundary of the Rockies exists in the Rocky Mountain trench, which forms one of the most prominent depressions of the entire Cordillera. It extends from south of the 49th parallel at least to the Liard river, a distance of nearly 1,000 miles. Throughout its length it is the course for numerous rivers of varying sizes flowing either north or south. Northward fr jm the inter-national Boundary it is occupied by the Flathead river (north flowing), the Kootenay (sjuth flowing), the Columbia (north), the Fraser (north), the Parsnip (north), the Finlay (south), the Kachika (north), and the Highland (south). 1 Quoting Schofield: "One of the most peculiar features of the trench, whose walls on both sides rise on an average 4,500 feet above the valley floor, is the f.ct tnat it is occupied by streams which vary greatly in size. For example, the Kootenay river enters the trench as a large river from the north, while less than a mile away from this point, the north flowing Columbia has its beginning in two small lakes. In the same manner, the south flowing Canoe rises and continues as a very small river to join the mighty Columbia in the trench. From these examples, which might be greatly amplified, it can be seen that the size and depth of the valleys which unite linearly to form the Rocky Mountain trench bear no relationship to the size of the streams which occupy them,which is contrary to the results of normal stream erosion. 1. Royal soc.of Canada. 1920. Pt.III. p.63-64 "The general trend oi the regional drainage is toward the trench, except in the case of the Kootenay River and the Columbia River, which break through the western wall of the trench and reach the Pacific, while the Peace river cats through the eastern wall and finally reaches the Arctic........ "The width of the trench averages 4 to 6 miles but in places ......is much greater. The floor of the trench is usually flat or slightly rolling, and is covered generally by the unconsolidated gravels and silts of the Cenozoic. The walls of the trench usually rise abruptly from the floor, especially on the eastern side, where it is usually precipitous. This feature is the most noticeable in the southern part of the trench." The line of demarcation between the prairies and o the mountains is even more prenounced from latitude 49 to o latitude 53 than the westerly limit of the mountain system. * prominent escarpment, 2,500 to 3,000 feet high, in places almost perpendicular, and composed largely of massive-bedded gray limestone strata, sharply defines tie mountain topo-graphy from the rounded-topped ridges, for the most part oovered with vegetation, that form the inner foothills. This topographical feature is the result of overthrusting which occurred during the period of mountain building. The more massive rocks of the west were thrust in a north-easterly direction over the softer strata forming the under-structare of the plains. At certain places along the base of this escarpment the plans along which the faulting occurred is exposed, and is generally known as the Lewis Overthrust. North of the Athabasca river, this front escarpment is not so marked because the extent of overthrusting wag net so great, the faults having to a certain degree bean replaced by folds. 1 Stewart's general description of the foothill region is: "The foothills form a belt, averaging 10 to 20 miles in width, bordering the east side of the Rockies for practically their entire length. They form a distinct topographic feature, though they gradually merge into the plains to the east. The mountains generally rise abruptly from the foothills, but in a few places the two are so nearly alike in height that they can be distinguished mainly by the lack of soil and vegeta&on on the limestones and quartzites forming the front range." The base level of the Rockies on the foothills side is much higher than on the western side. On the east, as ascertained by taking the average level at which the larger streams leave the mountains proper and pass into the foothill region, it is about 4,360 feet. On the west, the average elevation of the Columbia-Kootenay vatley is approximately 2,450 feet. In consequence of this difference, the passes traversing the Rockies have a steep and sudden descent to the west of the watershed in contrast to the more gradual slope to the east. Due to their structure, the Rocky Mountains may be divided into two topographic areas trending parallel with the system. The boundary between these is approximately on a line north and south from Banff. The mountains in the eastern division derive their form from the fact that they are thrust blocks with a sharp eastern face and gently II Stewart. J.S. Geol.Surv.Can. Hem.112. 1919. p.11 dipping westerly slopes; those in the western are in the main the results of open folding and hence present the appearance of folded mountains modified by erosion and some normal faulting. The forms assumed by typical mountains are well 1 summarised by Allan: "The influence which the rock structure has had upon the present scenery in the Rocky Mountains is so marked t h t brief mention must be made of it here. The type of sculpturing produced by weathering depends on the composition of the rock and also on the existing structure. Seven distinct types of mountains can be recog-nised in this area: (1) "Mountains composed of horizontal strata tend to weather into pyramid forms, usually broadbased, sloping regularly to the apex. The slopes depend on the character and thickness of the composing strata. Examples are formed principally along the watershed range, such as Robson, Pyramid, Geikie, Forbes, Lyell, Temple, Deltaform and AsBiniboia. (2) "In slightly inclined strata the pyramid outline is slightly lopsided, as seen in the Aylmer, Goodsir, Ball, Balfour or Crowsnest. (3) "¿hen the strata is moderately inclined the block type of mountain is produced, as in Bundle, Cascade, Roche l.iiette and many peaks in the first three ranges of the Rockies. (4) "In vertical or steeply dipping strata, mountains like Edith, Hole-in-the-^all or Spike Peak are produced. (5) "Anticlinal mountains are rare, as uparched strata soon become incised and eroded along the central axis. Knobs like Stoney squaw at the south end of Cascade Mountain illustrate this type rather poorly. 1. Allan. J.A. Can.Alpine Journal, 1917 (6) "Synclinal mountains are common and indicate mature erosion since the syncline at one time occupied the trough between up-arched masses of rock. Folding Mountain, President Range, Castle Mountain Range and the range in which Mt+Melar and Mt.Hector are situated give examples of this type. (V) "¿hen thick beds of resistant rock are inter-bedded with less durable strata, "weather terraces" are formed, as seen in Amlskwi Peak, Pilot. Redoubt, and also in Mt.Molar. This last type is olosely related to those mountains which belong to either the first or second classes." Ranges of the Rocky Mountains The Rocky Mountains consist of numerous ridges and ranges. inly a general summary of these can be given here, due mainly to the fact that they are still largely unexplored and often without names, especially in their more northern portions. 1 At the 49th parallel, Daly has recognised four ranges. The most easterly or front range of the Rockies in northern Montana extends into Canada f r about throe miles. At that distance from the boundary the mountain front turns sharply to the west and runs in that direction for about six miles, presenting a steep face to the north. Beyond, the oontiunity of the mountains is broken by the deep depression occupied by .Taterton lakes and ,/aterton river. To the west of the depression rises the Clarke range, which forms the front range north to the valley of the Castle river* ./est of the Clarke range, the Flathead river flows. The 1. Daly, R.^. Geol.Surv.Can* Mem.38. 1912. Pt.l. p.29 MacDonald Range lies west of it. This range is separated from the Galton, the most westerly range of the system at the 49th parallel, by the ,/igwam River. The northern limit 1 of the MacDonald Range is placed on Dawson's map at the North Kootenay pass and the Galton at Elk River. Mountains between the North Kootenay and Kaaanaskis passes ^ Beyond the North Kootenay and the Crowsnest passes, the mountains became well defined. The Livingstone range, continued farther northward by the Highwood range, forms the outer ridge of the mountains, and extends with slight interruption for a distance of 80 miles to the Elbow river. A second limestone ridge is formed by the Flathead and High Rock ranges, which lie nearly parallel to the first and have, like it, a slight convexity eastward. The Elk mountains continue this line to the sources of the Elbow, where the space between this and the outer range is nearly filled by the Intercalated Misty range. Farther west, the ./i-suk-i-tahak range forms a third imperfect parallel range. Beyond this is the very high and rough range to the west of Elk river, between which and the Hughes range, bordering the trench, a wide area is not well known. 1* Dawson. Geol.Surv.can. Ann.Rep. 1885. Pt.B. p.22 2. Idem. -27-MwcntalBB between Kananaskis and Vermilion Passes The mountain region between the upper part of the Elbow river and Kananaskis pass on the south, and the Bow river and Vermilion pass on the north, lacks the wide Cretaeeoua valleys found in the part last described. It is composed of 8 to 10 main ranges, with but two wide inter-vening valleya, one running from the head of Kananaskis to Spray river, the other holding the headwaters of the south flowing Kootenay. The parallelism of these ranges is not lass well marked, but their continuity is frequently interrupted both by transverse valleys and by an echelon-like arrangement which exists among them. Fisher's range here constitutes the western front of the mountains. Behind it a second ridge is formed by a somewhat irregular range which ends in the Pigeon mountain on the Bow. The Opal mountains and connecting elevations ending in Mt.Bundle form a third range, while the Kananaskis and Goat ranges with Terrace mountain, constitute a fourth. The Spray and Bourgeau mountains are the best known portions of a fifth parallel, and a sixth runs northward from Pilot mountain but dies out before reaching the /hite Man's pass. The Blue mountains and connecting mountains ending in Mt. Ball on the Vermilion pass, form a wide and somewhat irregular seventh range. Between this and the important 1. Dawson, G.M. Geol.surv.Can. Ann.Rep. 1885. Pt.B. p.22 -28-ridge formed by the Mitchell and Vermilion ranges there are probably two ahert intercalated ranges, of which the ends are seen en the Cross river. The Brisco and Stanford ranges constitute the western elevations of the Rockies in this part, and are wider and more persistent than most of the ranges mentioned above. North of the Bow river and Vermilion pass the parallelism of the constituent ranges is continued in the Pairhelme mountains, the Palliser and Saw Back ranges. The Bow range and %aputtehk mountains, cut across by the Kicking Horse pass, together form a very massive range, which, to the ^est. in the vieinity of the pass, become broken up into rather irregular groups of mountains. The . lefty Ottertail mountains are continued to the north-wast by two ranges, the Van Home mountains and Mt+Runter range. The Beaverfoot range, really a continuation of the Briaco range, fronts on the Columbia Valley. Ranges north to the Peace The mountain ranges northward of the areas already described have not been so specifically mapped and named as these to the south. The front range north of the sawback and Palliser ranges is the Bighorn, and at the wescern border of the Rockies, the spencer range lies north of the Van Home. The general topographic features are carried on north to the Liard thaugh the area becomes narrow. The Takakkaw Falls, Yoho Valley. UBC Scanned by UBC Library Lake Minnewanka, near Banfi. Plate IV. -29-aeantains to the Yallowhead pass are extremely ragged and contain many high peaks and great snow fields. The eleva-tions onlminate in Robson Peak beyond which they become lower aa the Liard river is approached. Drainage In the Rooky mountains is found the watershed between the eastward and northward flowing streams which reach either the Hudson Bay or the Arctic, and the waters draining into the Pacifio. Two interesting examples are found in the Peace and the Liard rivers which cat across the entire system. The watershed follows no direct coarse, paralleling the general trend of the ranges, but shows a 1 considerable variation in its directions. Dawson says: "No single ridge or system of elevations constitutes the watershed range in this part of the mountains (49th to 53rd parallels), nor does the portion of the mountains characterised by the greatest conneoted areas of high mountain country and crowned by the higher peaks coincide with it." In the main, the divide is nearer to the Rocky Mountain trench than to the foothills. The slope to the trench is much steeper as well as shorter than the slope to the plains, hence the rivers draining into the trench are short and swift, and those flowing easterly are longer and larger and have a more gradual gradient. 1. Geol.3urv.Cen. Ann.Rep. 1885. Part B. p.23 Looking across the Bow River; Mount Rundle at the left, Sulphur Mountain at the right. UBC Scanned by UBC Library Moraine Lake and the great circle of the Ten Peaks. -31-the Elk, Eeetenay and the Flathead which are all southward flowing rivers* The Bow follows a rather remarkable course. After flowing in an anticlinal valley it turns eastward and breaks completely across the series of ridges which form the Sawback range. There it reaches an important Cretaceous infold, and after following it for a number of miles to the south-east, again tarns nearly at right angles, and breaking through the outer ranges, reaches the foothills. The North Saskatchewan and the Athabasca rivers are among the largest rivers draining the Rockies. Their main streams cat quite sharply eastward thfoagh the ranges while numerous tributaries drain longitudinal valleys. The Peace and the Liard are the sole examples of rivers catting entirely acrosE the Rockioa. The Peace drains not only the mountains in this part, but moreover receives the waters from areas drained by the Parsnip, Finlay and Omineca rivers. At the Liard the Rocky System breaks sharply and only continues northward as the Mackenzie mountains IOC miles further east. The Liard occupies this break, carrying through it water from regions to the north, 1 south and westward. Quoting McConneH "Rising in a country west of the Rocky mountains, the Liard falls rapidly toward the east, the difference in elevation between the mouth of the Dease and Mackenzie being 1,650 feet...... The Rocky mountains are consequently interrupted in this part of their length. H Geol.Soc.Can. Ann.Rep. 1888-1889. p.34D Plate VI. Plate VI. -32-"The width of thia persistent range probably averages throughout about 50 miles; and its main physical and geological features are almost identical in all parts of its length.... "South of the Liard the bare limestone ridges are ranged in parallel lines and are sur-mounted by sharp zig-zag knife edges or jagged serrated crests. The ridges have a general strike of N.30 The spar of the mountains which crosses the river consists of a greyish and moderately compact limestone*" As would be expected in a mountain system of parallel ranges such as are found in the Rockies, the valleys and basins are well developed. Particularly in the area of the sain line of the C.P.R. and southward, large north and south depressions occur. The larper of these valleys are occupied by the more important rivers of the system. Superficial deposits of glacial drift and alluvium are cotton features and many of the valleys of the south and eastern parts are floored with infolded Mesozoic rocks, in places containing coal seams. All the valleys have the typical U-shape consequent on glacial action. The topography of the major trunk valleys has been much changed by the morainal debris left by the disappearing valley glaciers. In many cases the outlets of these valleys became blocked and in the lakes formed behind these barriers, gravels, sands and clays ware deposited. These deposits are exposed in terraces along the sides of the larger valleys. Emerald Lake. Lake O'Hara. Scanned by UBC Library Plate VII. -33-Lakes The lakes found in the Rockies are neither large nor numerous. The^ possess, however, an excellence of scenic beauty which rivals that of any portion of the globe. "Glaciers have been the cause of the formation of the Rocky Mountain lakes. Three prominent types might be mentioned. Those occupying rock basins carved out by glacial action such as Lake Agnes at Laggan, Turquoise and Margaret on the upper Bow, Lake Magog at Ht.Assiniboine and Berg Lake ut Robson peak. "Such lakes as Moraine, Louise. Minnewanka, Kinney, Maligne, Pyramid and ..aterton occupy basins formed behind morainal detritus. A third type of lake is represented by such as Hector, Bow, gmarald, Gloria and Marvel. The barrier in this case consists of the outwash of gravel and sand from the front of the ice. "3. Glaciers So high a system of mountains is naturally produc-tive of glaciers and ice fields in abundance throughout its length. The presence of great glaciers in the C.P.R. sec-tion has ina&eased the value of this area as a tourist resort due to their addition to the attractions of mountaineering. At present the glaciers of the Rockies are retreating, and notable diminutions in length have taken place within livipg memory. 1. Allan, J.A. Can.Alpine Journal. 1917 -34-Parks It were needless here to elaborate on the beauty of scenery in the Rockies. That is well attested to by the fact that they contain no less than seven national parks which have been set aside because of the unusual attractive-ness of the areas which they embrace. Their qualities are set forth by numerous booklets issued by the railroad companios,in glowing terms, which are fortunately well supplemented by excellent views. The parks may be reached either by rail or motor road, the latter of which are rapidly opening the mountains mere and mare to travellers. -51-CHAPTER 11?. . ,,;.< GENERAL GEOLOGY Introduction The Rocky Mountains are formed almost entirely of sediments* In comparison to most mountain systems the strata are relatively undisturbed and little metamorphosed. The strata are remarkably conformable and no great erosional breaks are known* Beltian rocks are represented mainly in the region contiguous to the 49th parallel. Paleozoic sediments scour throughout and constitute the bulk of the exposed rocks. Mesozoic formations are found chiefly in the eastern division and north of the Kootenay Pass. Tertiary rocka are recorded in the Kiahenana valley in the aouthern Rockies and in the Rocky Mountain trench in the vicinity of the Pinlay river. Pleistocene and Recent are found aa superficial deposits in the valleys and basins. Igneous rocks are conspicuous by their scarcity and are not known north of the area of the main line of the C.P.R. -36-Reoresentative Tattle* of Formations 1 1. Sections at the 49th Parallel Lewis Serloe Galton Series Beliiao Lowest Middle Cambrian Llsconformity Kintla Shoppard Pnroell Lava Siyeh Crinell Appekanny Altyn Vaterton Total: 800') 600') 260' 4,100' 1,600' 2,600' 3,600' 2 0 0 ' 13,420' Roosville Phillipe Gateway Piircell Lava Siyeh 'ig-wam Mao Donald Hpfty Altyn 1,0)0' 500' 2,02ß' 310' 4, OX)' 1,200' 2,300' 776' 660' Total: 12,100' 1. Daly, R.A. Oeol.Surv.Can. Memoir 38. -37-1 g. Section at Berth Kootenay pass Devonian — — — — -----Jefferson limestone 800' Disconformity Middle Cambrian 435' Disconformity P r e - C a m b r i a n v — - — — Lewis series 2 Section at Elko Devonian Jefferson limestone 300* Disconformity Middle Cambrian --—Elko formation 90' " " Barton " 80' Lower Cambrian Burton " 17' " " Cranbrook con-glomerates 1' Disconformity Pro-Cambrian — — G a l t o n series 3 4. section at Ram Creek Middle Cambrian -—Elko formation 1,000' Burton " ) ) 475' Lover Cambrian " * j Cranbrook conglomerates) 1,220' Unconformity Late Pre-Cambrian- --Toby " 40' Disconformity or Unconformity H Adams & Dick, Can.Commission 1915. pp.8-13 2. Schofield, S.J. 6eol.Surv.Can. Mem.76. 1915. p.42 3.( Idem Idem Hus.Bull.35. 1922. p.15 ( ¿alker, J.y. Idem Hem.148.1926. p.17 -38-4. Section at Ram Creek (Continued) Beltian- -Roosviile Phillips Gateway Siyeh Purcell lava Siyeh Kitchener Creston Aldridge Base unexposed formation 1,000' 400' 1,500' 500' 50' 4,000' 4,500' 5,000' 5,000' w ti n M t : M f! M Section at Blairmore 6. Recent and Pleistocene—Superficial deposits Cretaceous Allison Creek sandstone 1,9)0' Benton formation 2,7 30' Crowsnest voloanics 1,150' Blairmore formation 2,5)0' Kootenay " 565' Jurassic Pernio shales 75)' Devono-Carboniferous 10,000' 2 Section in Flathead Area Recent and lleistocene-superficiai deposits Tertiary Kishenena formation Cretaceous -Flathead beds ) Alk conglomerates) kootenay formation Jurassic —Fernie shales Triassici?) Carboniferous Devono-Carboniferous 7)0' 6,5))' 3,5)0' 3,j)0' 2,500' 2,300' 3, 30' H Leach, ¿.J. Geol.Surv.Can. Sum.Rep. 1911. p.193 2. Rose, B. Idem Idem 1917. p.29-C 1 T. Section at Windermere Recent Alluvium Pleistocene Glacial drift Unconformity Silurian- -Brisoo formation ) ) 260' Richmond-- — — — B e a v e r f o e t " ) (?) dCnah quartzlte 167' Disconformity Loser Ordivician Glenogle shales 2,000' Lower Ordivician ) Upper Cambrian ) - — - — — Goodsir formation 300' Upper Cambrian Otiertail " 1,000' Unconformity Late Pre-Cambrian Horaethief " ) 4,000' Toby conglomerate j 50-2,000' 2 8. Section at Lake Minnevanka. Banff Cretaceoua- Upper Ribboned sandstone) 550' Kootenay 2800' Lower " " Jurassic Pernie formation Triasaic — spray River " 1,500' Permian — Rocky Mountain quartzite 600' Pennsylvanian and Missiaaippian — — Bundle formation 1,5)0' Missisaippian— — - Banff " 1,200' Devonian— — atinnewanka" 1,000' 1. dhlker, J.F. 6eol.Surv.Can. Mem.148. 1926. p.7 2. Shimer, H.<?. Idem Mas.Bull.Ro.45.1926.p.3 (Cretaceous found east at Bankhead) \ - 4 0 -8. Section at Lake Minnawanka, Banff (Continued) (?) — --ghost River formation 300' Cambrian --------—------cathedral " 1 9* section in Field Map Area Post Cretaceous Igneous complex Silurian- Halysites beds 1,850' OrdAvician— Graptolite shales 1,700' Goodsir shales 6,340' Upper Cambrian Ottertail 1,775' Chancellor 4,500' Sherbrooke 1,375' Paget 360' Bosworth 1,855' Middle Cambrian--- —Eldon 2,728' Stephen 640' Cathedral 1,595' Lower Cambrian* Mt. .¿hyte 390' St.Piran 2,706' Lake Louise 105' Fairview 600' Conformable in some places Pre-Cambrian Hector 4,590' Corral Creek 1,320' 2 10. Section at Roche Miette Recent am Pleistocene—-superficial deposits Lower Cretaceous— —Kootenay formation Jurassic--——— Pernio shales H Allan. J.A. Geoi.Surv.Can. Mëix.55. 1914. p.63 a* Bowling, D.B. Idem Sum.Rep. 1911. p.206 41 10. section at Rocha Mie&te (Continued) Triaeeic apd Permian (Carboniferous ( 3,000' (Devonian Silurian (?) Cambrian 1 11. section in Robson Peak Area ./alcott Burling Ordivician -Robaon 3.000' Unnamed 375' Upper Cambrian--Lynx 2,100* Lynx 5,000' Middle Cambrian— -Titkana 2,200' Titkana 2,500' Mumm 600' Absent Hitka 1,700' Absent Tatay 600' Tatei 1,000' Che tang 900' Che tang 950' Adolphus 400' L^er Cambrian-— -Hota 800' Hahto 1.800' Mahto 1,200' Tah 8)0' Mural 1,000' McBaughton 500' Unnamed 400' Di sconformity Pre-Cambrian ---—Miette 1. (Jalcott. C.D. smith, Inst. Misc.Coll. Vol.57.Bo.12. f - 1913. pp.327-343 (Burling, L.D. Geol.soc.Am. Vd.34. 1923. p.726 -42 DESCRIPTION OF FORMATIONS BELTIAN The oldest rocks known in the Canadian Rockies are the northern continuation of the Belt series of Montana and 1 Idaho. The age is Algonkian. Included by ¿alcott in the Beltian are the strata which occur between the general unconformity that marks the base of the Cambrian, whether Lower, Middle or Upper Cambrian, and another unconformity at the top of the basement complex, wich he classified as Archean. Beltian formations are represented best in the Rookies in the vicinity of the International Boundary where they make up the bulk of the ranges and consist of 13,000 feet of sediments *?ith the base of the series unexposed and the top lost by erosion. The strata, known as the Levis Series in the eastern part of the Rocky mountains and the Purcell Series in the west, consist very largely of argillites, no?? siliceous and partly recrystallised, but with one very thick horizon of impure limestone and argillite in the upper part. Other thick, siliceous limestone or dolomite formations occur in the eastern part of the section and the associated strata on the yhole are finer grained than the corresponding beds to the west. in the upper part 1. Valeett, C.D. Geol.Soc.Am. Vol.10. 1899. p.200 -43-h*g*itie lavaa * few hundred feet thick oocnr at the same general constant horizon. * The Beltian ia exposed northward to North Kootenay Pass where it disappears ander later rocks. It is foand along the Rocky Mountain trench north to Windermere Lake, and in the trench in the vicinity of Finlay river. It outcrops in the Bow River area and at Yellowhead Pass, and it ia probable that with farther exploration it may be found to underlie the entire Rocky Syatem in Canada, especially since probable Beltian rooks outcrop in the Mackenzie 1 mountains. In a survey of formations of the Rocky Mountains, the problem of the limited occurrences of Beltian rocks in areas other than that contiguous to the 49th parallel, is one that 8uggeats itself as worthy of detailed analysis. Beltian Rocks at the 49th Parallel 2 The Lewia Serle8 Waterton Formation The Waterton dolomite is the oldest known rock on the 49th parallel. It is exposed at the point where Oil Creek falls into Waterton Lake. Here it is conformably overlain by the Altyn. It consists of an exceptionally strong and massive dark grey carbonate rock, weathering dark grey to brownish H Geol.8urv.Can. Sum.Rep. 1922. p.75-B 3. After R.A.Daly, Idem. Mem.38. 1912. pp.42-82 -44-grey tad sometimes buff. Bezlaga for oil near Oil Creek show 1,500 feet of the Lewi* Series not outcropping. Altyn Formation Exposures of the Altyn are known chiefly along Oil Creek where it is 3,500 feet thick. The rock may be called a dolomite end contains arenaceous magnesian limestones, dolomitic sandstones, dolomitic grits and pure dolomites in order of relative importance. A tripartite division is recognised: an upper member of thin-bedded, siliceous dolomite, a middle member of thick-bedded, massive, arenaceous dolomite and a lower member of generally thin-bedded, siliceous dolomite contain-ing sandy beds towards the base. In this formation have been found numerous fragments of what are probable foaailB which have been identified aa Beltina danaii by Walcott. If true fosails, they are one of the oldest species yet deacribed. They may have some value as horizon markers. Appekuimy Metarxillite The Appeknnny is generally found exposed in the 1 oliffs throughout the C3aa*a and Lewis rangea. Willis says: *It occurs every-he** above the Altyn limeatone along the eastern front of the Lewis Range above i. Willis, B. Ball. Ceol.Soc.Am. Vol.13. 1902. p.322 Flathead Valley, and is there the lowest member of the series seen from Kintla Lakes southward to MacDonald Lake*" A complete section is found on a ridge south of Oil City. This formation is a masB of highly siliceous, argillaceous sediment. The content of silica is often so great that the rock might well be called an impure quartzite. Grinnell Hetargilllte The Grinnell argillite outcrops continuously along the eastern side of the Lewis Range and its spurs. It Occurs in its proper stratigraphic position between the forks of the Belly River and west in the northernmost extremity of he Lewis Range. In the Clarke Range it outcrops in the vicinity of Upper Kintla Lake. The formation is a mass of red rocks of predominant-ly shaly argillaceous character. The beds are generally ripple-marked, exhibit mud-cracks and the irregular surface of shallow water deposits. siyeh Limestone Conformably on the Grinnell is the conspicuous Siyeh formation* It constitutes the principal upper part of the Lewis Range and forms the massive peaks between yaterton and the North Fork drainage lines. Due to its capping of resistant Purcell lava, and its own resistant -46-nature it stands up in precipices thousands of feet in height. "The Siyeh is in general an exceedingly massive limestone, heavily bedded.......It is dark blue or grayish, weathering buff, and is so jointed as to develop large rectangular blocks and cliffs of extraordinary height and steepness." Prominent in the Siyeh is a molar-tooth structure caused by the weathering of layers of calcium carbonate with the consequent relief of ribs of siliceous, magnesian lime-stone. She^pard Dolomite Conformably on the Purcull Lava in the Legis and Clarke Ranges is a group of strata called the sheppard 2 quartzite by Willis . It is generally distributed through-out these ranges. Though the colour, compactness and general habit of the Sheppard rock are those of an impure, flaggy quartzite, thin sections show it to he largely composed of dolomite, and that quartz occurs as minute grains rather evenly dis-tributed throughout the mass. The staple rock is than a siliceous dolomite or dolomit-ic quartzite. Kintla Metargillite In the field the Kintla formation is a conspicuous element of the Lewis Series. Stratigraphically, the 1. /illis, B. Bull. Geol.Soc.^m. Vol.13. 1902. p.323 2. Idem p.324 -47-highaat known member of the series, the Kintla commonly occurs on the higher summits and thus above tree line. It consists of thin bedded argillite and subordin-ate quartzite. An amygdaloidal lava flow of 40 feet is found near the bottom. A special feature of the argillite is the great abundance of easts of salt crystals. Ripple marks and sun cracks are abundant. Features of the series 1 Quoting Daly: "The recurrence of microperthite found in most of the clastic beds through the entire Le?is Series sho.s that probably one great crystalline terrane furnished the detritus during the deposition of the whole series.....The great freshness of the feldspars in most of the beds suggests that the erosion of that terrane and the process of sedimentation were rapid It is probable that the climate in which disintegration overtook chemical weathering was arid. The presence of salt crystals in the Kintla rocks strengthens the probability." 2 The Galton series Westward from the Flathead River, the mountains are composed principally of the Galton series which is the western extension of the sa-ae stratified series that form the peaks and massifs of the Clarke and Le?is Ranges. Some of the formations are clearly continued and bear the same names, others contain enough individual characteristics 1. Geol.Surv.Can. Mam.38. 1912. p.83 2. ^ftor Daly. Geol.Surv.Can. Hem.38. 1912. pp.97-112 to merit special names, while same formations outcrop only in the MacDonald range. Altyn Dolomite afest of the Flathead, the Altyn outcrops in two localities - on the ridge overlooking the Flathead from the west and culminating in Mt.Hefty where 660 feet are shown at one point, and in a canyon six miles west of the Hefty ridge. Here 120 feat are exposed. Stratigraphic relations and composition are similar to the Upper member of the Lewis Altyn. In each ease the rock is a siliceous dolomite. Hefty Quartzite In the MacDonald ran^e the Altyn is conformably overlain by a froup of strata which are exposed at the same two localities. The staple rock of the formation is a heavily-bedded red or reddish-grey, fine grained sandstone. As a rule it has not metamorphosed to a true quartzite. Sun cracks and ripple marks are common at various horizons. The formation passes upward with some abruptness into the MacDonald limestone, and there is some dovetailing with the ¿ltyn below. From its position and petrographic nature it is likely that the Hefty is the coarser grained equivalent of the lower Appekunny in the Lewis series. -49-MacDonald Metargillite Above the Hefty formation is a thick division of beds which indicates long continued deposition of rather uniform sediments* These rocks underlie an extensive part of the MacDonald range. The formation is notably homogeneous, the principal rock phase throughout being a highly siliceous argillite or metargillite. Sun cracks and ripple marks are abundant in many horizons from summit to base. ,<lgwam Sandstone and Metargillite Two exposures of the wigwam are known near the International boundary. The formation consists of a mass of fairly homo-geneous red or brownish-red sandstone, interrupted by partings of red, siliceous metargillite* sun-cracked, ripple-marked and sometimes cross-bedded horizons are found. The Vigwam is evidently the western equivalent of the Grirmeil of the Le^is beries. Slyeh Limestone The general equivalence of the Lewis and Galton Series is. lithologicaily, most evident in the t^ick formation overlying respectively the Grinnell and ¿igwam beds. Great similarity is obvious in age, composition, structure and -50-orlgin. More or lese complete sections are found on the eastern slope of the Rocky Mountain trench, along Phillip's Creek and Wigwam River. The general nature is like that of the Lewis Siyeh, namely, a massive limestone with argillaceous layers, sun cracks and ripple marks are numerous and molar-tooth structure is very prominent. Gateway Metargillite and Quartzite A striking difference in thu character of the Lewis andGnlton series is to be found in tne nature of the beds lying coitfornably on the iurcell Lavas in the respective ranges. In t o Galton, the bads between the purcell Lava and the red beds equivalent to the Kintla of the Le is, have a much greater total thickness than the Lheppard and a quite dif..'erent composition. The formation includes two meubers of unequal thickness. The lower nember, resting imme-diately upon thj Purcell Lava, contains beds suggesting an identity of origin jith the Shejpard. It is 125 feet thick. The upper neiaber is about 1,850 feet. It is a fairly homogeneous mass of thin-bedded, highly siliceous motargillite. Ripple marks, sun cracks and salt crystal oasts are plentiful. The position, composition and general structure of the lower dolomitic oenber are features directly correlating it with the Sheppard formation of tha eastern ranges. -51-The Sheppard thus thins rapidly to the west. The thick upper member of the Gateway, carrying abundant salt crystal casts, is almost certainly of contemporaneous origin with the lower part of the intla, and like it, was doubtless deposited as a continental deposit in an arid climate. Phillips Ketarglllite The Phillips consists for the most part of about 800 feet of dark, purplish or brownish-red, fine-grained to compact metargillite and metasandstone, in thin, alternating beds. The general composition, c lour and field relations of the Phillips are so similar to those of the upper part of the Kintla that they are, in the main, stratigraphic equiva-lents can hardly be doubted. Roosville Uetargillite The Roosville forms the highest member of the Galton series. In the boundary area it outcrops on a peak near Phillip's Creek Cascade, erosion has removed the upper part of the formation, but 600 feet of the beds remain. The formation is essentially made up of thin-bedded, siliceous metargillite. Numerous sun cracks and ripple marks exist. The materials of the upper member of the Galton as well as the others, show evidence of static metamorphism. -52-though the older and deeper members naturally are in a more advanced state, but it is clear that the Roosville, like the Kintla of the Levis, has been buried beneath thousands of f e e t of still younger strata, doubtless including the heavy Devonian and Carboniferous limestones. The formation appears to be *ounger than any beds belonging to the Lewis series. It may be the equiva-lent of an unexposed upper division of the ¿intla, or may represent the western extension of a distinct formation. 1 Beltian Rocks at Ra^ i Creek Most of the Pre-Cambrian rocks of Ram Creek section have been described either under the Levis erias or the Galton series. only those formations which do not occur in those series will be dealt with. "The various members of the lurcell series from the Aldridge to thj Roosville have been recog-nised as far north as the vicinity of Ram Creekp on the east side of the Rocky Mountain trench." Aldridge Formation The Aldridge formation is made up of a series of argillaceous quartzites, purer quartzites and argiilites. The argillaceous quartzites form about three-quarters of the whole series and occur in beds with an average thickness 1. ¿chofield, 3.J. deol.Surv.Can. ^us.Bull.Ro.35.1932.p.11 2. talker, J.F. Idem. Hem.148. 1926. p.7 -53-ef on* toet. They are fine-grained rocks, dark gray to black on fresh fracture, and weather rusty brown, which is the moat distinctive feature of the formation as a whole. Creston Formation The Creston formation passes by gradual transition into the overlying Creston quartzites. It embraces a succession of greyish argillaceous quartzites and purer quartzitea whose beds average about one foot in thickness. They are light grey on fracture and weather in greyish tones in contrast with the rocks of the underlying Aldridge formation. Kitchener Formation In comparison with the underlying Creston and Aldridge formations, the most notable feature of the Kitchener is its content of lime. It consists of calcareous and argillaceous quartzites and impure limestones in beds about 6 inches thick. Toby Conglomerate *....**In the Ram Creek section, a remnant of the Toby conglomerate rests conformably on the R008Ville formation......Two and a half miles to the north, the 40 feet of shale and conglomerate represented in the i'oby conglomerate, increases to a thickness of 800 feet....... 1. ¿alker, J.?. Geol.surv.Can. Mem.148. 1926 p.^7 -54-The nature of the Toby conglomerate is extremely variable. The matrix may be largely slate, limestone or of a siliceous nature. The boulders may vary as much. The percentage of boulders to matrix is also variable. The materials composing the conglomerate has not travelled far. In all cases the boulders can be identified with the underlying series. The average size of the boulders is about 4 to 13 inches. 1 Pre-Uambrian Rocks at Windermere Only one pre-Cambrian formation has been identified in the Rocky Mountains in this area. It is of an age later than the youngest of the Galtan aeries. Horsethief Formation The Horsethief formation, of late pre-Cambrian age, outcrops at intervals along the front of the Stanford Range from Windermere Cr ek south to Upper Columbia Lake. It is made up in lar^e part of grey, green and purplish slate with several lenticular beds of coarse quartzite and pebble conglomerate . The numerous thin interbeds of blue-grey, crystalline, and mostly non-magnesian limestone, ;.-?hich occur at different horizons, form but a relatively small part of the \?holc. formation. 1. talker. J.y. Geol.surv.Can. Meia.148. 1926. p.14 -55-1 Walker places the age of the Horsethief formation as Ister than that of the Roosville. He correlates the Hector and Corral Creek formations with the Horsethief In preference to correlation with the Kintla-She^pard. Pre-Cambrian Rocks in the O.P.K.Main Line Area 2 Beltian rocks extend throughout the bottom and lower slopes of the Bow River valley from Bow Peak to Cascade on the C.P.R. East of Mt.Hector and in the lit. Richardson-Ptarmigan Peak mass, they rise in high hills both east and west of Pipestone River and continue eastward across Corral and ^aker Creeks before passing beneath the Cambrian on the north slopes of Castle fountain. The width varies from 3 to 6 miles. These rocks were grouped by JcConnell as part 3 of the Bow River series. Corral Creek Formation Corral Creek rocks are the oldest exposed in the C.P.R.section. The fortation consists of a grey sandstone underlain by a coarser quartzitic sandstone with an arkose-like conglomerate at the base. The nature of the con-glomerate suggests shallow water or near shore conditions of origin. H Ralker, J.F. Geol.Surv.Can. Mem.148. 1&26. p.19 2. talcott.C.D. Smith, Mis.Coll. Vol.53. No.7. p.427. 3.McConnell,R.G. Geol.Surv.Can. An.Rep. 1885. p.29-D. 4. Allan, J.A. Geol.Surv.Can. Sum.Rep. 1912. p.170 -56-1 Hector Formation The beds of the Hector consist of grey, purplish and greenish shale interbedded with bands of conglomerate. The best exposure is in the Bow Range east of Storm moun-tain* where it has a thickness of 4,590 feet. It thins toward the north-west. The contact with the Cambrian is conformable in the Bath Greek valley, but unconformable at two other places examined* Ire-Cambrian Rocks in Robson Peak Area 2 Jalcott reports Pre-Cambrian or Haitian rocks in the Yellonhead. Pass area. Here the topography of both these and the Cambrian rocks bears a striking resemblance to those of the Bo.v River Valley. 3 Miette Formation On both sides of the Yellohead Pass the Miette occurs in rounded, wooded ridges that rise some 3,000 feet above the Pass. The rocks consist of massive grey and greenish siliceous shales. Most of them suggest deposition of sand in muddy waters. 1* Allan, J.A. Geol.jurv.Can. Sum.RepJ 1912. p.170 2. ^alcott, c.D. Smith. Misc.Coll.Vol.57. No.12. p.340 3. Idem Idem Idem. -57-An erosional unconformity exists between the Miette and the Cambrian above. The thickness is 2,000 feet. 1 Pre-Cumbrian Rocks of the Pinlay River Area Rocks, probably of Pre-Cambrian age, are found on the east wall of the Rocky Mountain trench from the Peace River north to the Fox River. The rocks are mainly quartz-mica schist, mica quartzite and acid gneiss with a few small bands of impure limestone and lenses of hornblende gneias. All three main types are essentially quarts-mica rocks with small quantities of feldspar and garnet. j?he more abundant of the three principal rocks is the quartz-mica schist which constitutes aboui; three-quarters of t^e '¿hole. THE CAMBRIAN The Rocky Mountains are comprised in a very large part of Paleozoic rooks, and of these the Cambrian is the most complete and widespread. Jith the exception of the area at the 49th parallel, it is found throughout the entire system from the North Kootenay Pass to the peace and the Liard. During all of Cambrian it is likely that a sea way occupied the whole length of this no? mountainous area. No complete section of the Cambrian is found south of the C.P.R. Lower Cambrian is known in the Flathead area 1. Dolmage. V. Geol.Surv.Can. Sum.Rep. 1927. Pt.A. p.25-A ^ M H & t t *nd at Ram Creek; Hiddle . Bpper Sgg&gAan only la the Vindermere area. The classic Cam-brian area of the Cordillera, and indeed one of the finest Cambrian exposures of the earth, is found in the area of the main line of the C.P.B. where this system of rooks is com-plete in 18,000 feet of sediments. Northward, in the Robson Peak area, the Cambrian is probably also fully repre-sented where 12,000 feet of strata are found. On the Peace and Hard, McConnell reports rocks similar to his Castle-Bow series. 1 Cambrian at North Kootenay Pass Cambrian rocks have been found in the vicinity of north Kootenay Pass. They are composed of brownish lime-stones of unmeasured thickness. Fossil evidence places their age as Middle Cambrian. Here they are separated from the Kintla of the Beltian below by 200 to 300 feet of reddish white sandstones with a conglomeratic layer containing pebbles of white, opalescent quartz up to one-half inch diameter. This conglomerate marks a disconformity between the formations. 2 Cambrian Rocks of the Flathead Area Conglomerate of the same type as found at North 1. Adams & Dick. Can.Comm.Conservation. 1915. p.13 2. Roee, B. Geol.Surv.Can. Sam.Rep. 1917. p.296 -59-Kootenay Pass is found at the top of the Beltian in the Flathead area. The cnnglomerate and the limestone above 1 it are placed provisionally in the Lower Cambrian by Rose . 2 Cambrian Section at Elko Burton Formation. (Lower and Middle Cambrian) The Barton formation rests on the hoosville with no structural discordance, yet with evidence of unconformity 3 at the base. It consists mainly of greenish-black,calcareous shales with interbedded siliceous limestone bands. A thin 4 conglomerate is found at the base. Schofield places the lower 17 feet in the Lower ^ambrian and the upper 60 feet in the Middle Cambrian. Elko Formation (Upper Cambrian) The Elko rests conformably on the Burton. Its rocks are siliceous limestone and siliceous dolomite of 5 about 90 feet thickness. Kalker places it in the Upper Cambrian. 1. Rose, B. Geol.Surv.Can. Sum.Rep. 1917. p.296 2. Schofield, S.J. Geol.Surv.Can. Mem.76. 1915. pp.43-47 3. Idem. Idem. Mus.Bull.No.35. 1932. p.13 4. Idem. Idem. Idem. p.15 5. Walker, J.F. Geol.Surv.Can. Mem.148. 1926. pp.17 & 21, -60-1 Cambrian Section at Ram Creek The only occurrence of Cranbrook Conglomerates of any appreciable thickness in the Rocky Mountains is known at Ram Creek. Cambrian formations thicken greatly from Elko to Ram Creek. Cranbrook Conglomerates The Cranbrook is forned of massive white quartzite and a conglomerate mainly of quartz pebbles. The lower 5 feet contain rounded fragments of underlying Beltian rocks. The formation rests with unconformity or discon-formity on the Beltian. Its age is Lower Cambrian. Burton Formation The Burton formation is found in greater thickness at Ram Creek than at hlko. It grades from Lower Cambrian to Middle Cambrian. Elko Formation The H k o formation at Ran Creek is 1,000 feet thick. Its age is Upper Cambrian. 1. Schofield, S.J. Geol.Surv.Can. Hus.Bull. No.35. p.15 1 Cambrian at Windermere Only Upper Cambrian rocks are exposed in the Yinder-mere area because "the Ottertail formation overlaps here the complete Cambrian section as developed in the l.ocky ¡fountains 2 and rests on the Horsethief formation." Ottertail Formation The Ottertail formation is well exposed along the western face of the Stanford Range. It is made up of thick and thin-bedded, magnesian, crystalline limestone. It is a distinct lithologlc unit throughout the Stanford range. The thickness varies from 2,000 feet south of Fairmont Springs to 270 feet on the <?net end of Law Ridge. Y.ithin the Windermere area the Ottertail formation rests on the Horsethief, in some places conformably, and other unconfornably, and underlies the Goodsir conformably. In general it is the equivalent of the Ottertail formation of the Field map area, 40 miles distant alon?r the strike of the strata. Walcott has used the word Lyell (';) in des-cribing this formation in the Stanford Range. The correla-tion with the Lyell is made over a gap of 100 to 1?2 miles and across the summit of the Rooky Mountains. 1. R&lker, J.F. Geol.Surv.Can. Hem.148. 1926. p.21 2. Idem Idem p.21 -62-"South from the Tindermere area the formation is traceable for 25 miles to Ram Creek. It is the Elko formation of Schofield's Ram Creek section and of the described sections on Grainger and Sabine Mountains. In its southward exten-sion from the indermere area, the Ottertail rests successively on the Cranbrook quartzites, east of Sabine mountain, and the Burton or Mt. V.hyte formation on Grainger mountain at Ram Creek."! Goods ir Formation In the Windermere area th*. ^ oodsir formation is found throughout the Stanford ranr-e, varying in thickness and character. It is composed of shales with interbedded limestones. The formation is considered to he the lithologie and stratigraphie equivalent of the ^oodsir formation of the Field map area and of the Sabine and Ions formations of K'alcott. Its age is considered as including both Upper Cambrian and early Ordivician horizons. The Cambrian in the Main C.P.h.Section "The Cambrian is complete in the C.r.h.section with both lower and upper contacts exposed, ^here is a total of 18,578 feet which represents one of the thickest Caabrian sections yet measured in the world. It consists essentially of 3,800 feet of Hiliceous beds, chiefly quartnitic sandstone; 10,275 feet of calcareous and dolomitic limestone, and ^,500 feet of shale, much of which is calcareous."** 1. Talker, J.F. Geol.Surv.Can. Tern.148. 1926. p.23 2. Allan, J.A. Idem Guide Book No.8. Part 2. p.172 -63-Description of Formations (After Kalcott) Fairview Type Locality: Character: Thickness: Organic Remains Lower Cambrian North-east slope of Fairvlew moun-tain. Grey Quartzitic sandstones. 6 0 0 ' . Unknown. Lake Louise Type Locality: Character: Thickness: Organic Remains Both sides of Lake Louise, at its upper end; well shown in north-west and north sides of Fairview Moun-tain. Siliceous shale. 105' at upper end of Lake Louise. Lower Cambrian. St.Piran Type Locality: Character: Thickness: Organic Remains: South-east slope Mt.St.Piran. The basins of Lake Apnea an8 Mirror Lake are both excavated In this formation. Mainly grey quartzitic sandstones with a few bands of siliceous shales. At Mt.St.Piran 2,640'. Lower Cambrian in upper portion. 1. Walcott, C.D. Smith. Mis.Coll. Vol.53, no.l. pp.2-5. -64-Mt.Whyte Type Locality: Character: Thickness: Organic Remains Mt.Yhyte above Lake Agnes and east-ern slopes of Pope's Peak south-west of Mt.St.Piran. Alternating bands of limestone and siliceous and calcareous shale. Rorth slope of Mt.Bosworth 390'. Lower Cambrian. Cathedral Type Locality: Character: thickness: Organic Remains: Middle Cambrian Cathedral Mountain and Cathedral Crags, east of Mt.Stephen and south-east of Zlt.Bosivorth. Massive arenacioui limestone. and dolomitic Cathedral fountain 1,600'. Mt. Stephen 1,800'. Middle Cambrian. Note: In this formation the Monarch mine at Field is located, also other mineral prospects. Stephen: Type Locality: Character: hicknesc: Organic Remains: Bluish-grey and greenish-grey 11; estone and shale bands about 2,700 feet above railroad track on north and east sides of Mt.Stephen near -R'ield. Limestones and shales, calcareous and siliceous. Includes "Ogygopsis and "Burgess" shales. Mt.Stephen 562*. Loc^l development of "Ogygopsis" shales at summit. Middle Cambrian.Burgess shale prominent for its variety of orranie remains. -81-ElAon Type Locality: Character: Thickness: Organic Remains: Upper massive limestone of Castle Mountain, one or two miles north of idon switch on C.P.R. Massive, arenaceous, dolomitic Limestone ?ith a fe?7 bands of purer bluish-grey limestone. Castle Mountain, 5,728*. Jliddle Cambrian. Bosworth Upper Cambrian Tyre Locality: Character: Thickness: Organic Remains: Ridr-e extending north-.vest irom Mt.Boscrth and south-east base of Paf-ct Peak. Arenaceous, dolomitic limestones, maapive, thin-bedded and shaly *?ith bands of purple and grey, siliceous shales. Mt.bOKWorth, Rone observed. Payet Type Locality: South-east slo^e of Paget Peak be-neath the ^herbrooke formation which forms the hiph cliffs of rafot peak and Mt.Daly. The Pa^et breaks down more readily than the nhorbrooke, presenting a slightly broken cliff line. Character: Thinly bedded bluish-grey and oolitic limestones. Thickness: At Mt.Bosr.'orth 360*. Organic Remains: Upper Cambrian fauna. -66-Sherbrooke Type Locality: ./est slope of Mt.Bosworth, overlook-ing Sherbrooka Lake, 5 miles north of Rector* Character; Bluish-grey, arenaceous, dolomitic massive and thin bedded limestones with a few oolitic layers and cherty inclusions Thickness Organic Remains At Mt.Bosworth, 1,375' Upper Cambrian. Note: This formation includes the highest beds in the Bo*j Range in the vicinity of hector lass. The remaining Cambrian formations are all exposed in the western portion of the C.P.R* section between t^e Bow Ran^e and Columbia Vailey* Valley, underlies the Ottertail range and makes up a large portion of the Van home range. 500 feet are metargillites, '%ell cleaved along the bedding planes. These shales become much m o e highly cleaved toward the base of the formation so that the lowermost ¿¿,000 feat consist chiefly of phyllites, slates with argillites and a few interbedded layers of shaly limestone. 1 Chancellor ?he Chancellor formation floors the ottertail It consists essentially of shales. The uppermost 1. Allan, J.A. Geol.Surv.Can. Guide Book.Uo.8. Pt.S. p.179 -67 1 Ottertail The Ottertail consists almost entirely of blue limestone, massive toward the top and rather thin-bedded toward the base. .It has a thickness of over 1,725 feet in the Ottertail range, where it is well exposed in an almost perpendicular escarpment along the east side of the range. This limestone represents the highest series in the Cambrian in the western section of the C.P.R.saction. 2 The Cambrian in Robson Peak Area The area examined by ,ialcott in the Robson Peak area lies between Robson Peak and Moore Pass, a distance of 9^ miles. LO 'er Cambrian McNaughton The McNaughton rests unconforutably on the Beltian rocks* It consists of a light-grey, massive-bedded quartzltic sandstone. Tah Tab rocks are hard, green and purple siliceous shales with irregular beds of grey and purple, compact limestones interbedded in the central portion. 1. Allan, J.A. Geol.Surv.can. Guide Book RO.6. Pt.2. p.179 2. .¿alcott, C.D. Smith. Mis.Coll, Vol.53. No.12 Mahto Massive bedded quartsite sandstones with thin-bedded hard sandstones and dirty, greyish-brown shales in thin bands. HQta Massive-bedded arenaceous limestone in great bands of light and dark grey colour. Middle Cambrian Chetang Bluish-grey, thin-bedded limestones. Tatay Massive-bedded grey siliceous and arenaceous limestones. Hitka Alternating bands of grey, thin-bedded arenaceous limestones and siliceous, arenaceous ana argillaceous shales. Nmam Massive-bedded, grey siliceous limestone, weathering to grey and buff tints on cliffs. Titkana Massive-bedded, bluish-grey limestone in thin layers, interbedded with grey, siliceous, buff-weathering limestone that occurs in bands 50 to 100 feet thick. -69-Upper Cambrian Thin-bedded, blulshrgrey limestone i,7ith interbedded bands of light grey shale and at the base a band of about 200 feet of grey, greenish and reddish-brown shale. 1 Cambrian Rooks in the Pinlay River Area East of the Rocky Mountain trench in the Finlay River area the Rocky mountains consist largely of limestone, /here studied, it is for the most part quite pure and white or grey. Ro fossils have been found in the limestones, hut 2 because of their position above the schists, McConnell considered them to be a part of the Castie Mountain proup. ORDtVICIAN Early and Middle Ordivician rocks only are repre-sented in the Canadian Rockies. They are found in the ..'inderaere, C.P.R. and Robson leak areas. southward they decrease in thickness and disappear, but apparently extend an indefinite distance northward. 1. Dolmage, V. Geol.Surv.Can. sum.Rep. 1927. p.26-A a* McConnell. R.G. Geol+Surv.Can. An.Rep.Vol.7. 1894 -70-1 Ordivlcian Rooks in Windermere Area OlenoRle Shale This formation is found north and south of Windermere Creek. The lower part of the formation is chiefly black shale with interbeds )f a hard, mud rock and bluish limestone. The upper purt grades from a sandy shale to a thin-bedded, argillaceous sandstone. This sandy shale is missing in the more westerly exposures. This formation is considered to be the strati-graphic and lithologic equivalent of the graptolite shales of the Field map area. Burling rave the name Clenople to g these shales in 1922. An unbroken section has not yet been fou d at or near Clenogle. Wonah Quartzite In the Windermere area the '.onah occurs in a few places along the eastern part of the Stanford ranp-e. It is the etratigraphic equivalent of the quartzites at the base of the Halysites beds of the C.t.R.area. It rests, in the Windermere area, on what appears to he an erosion surface of the Clenogle shales and at two localities on the Coodair. It is separated from the formations below by a considerable 1. Kalker, J.F. Geol.Surv.Can. Mem.148. 1926. pp.24,25. 2. Purling L.D. Geol.Mag. Vol.69. 1922. p.456 -71-tim^ internal, but is overlain conforiably by the Beaverfoot-Brisco formations, the lower of which is of Richmond age. The wonah, then, may be of early Richmond ape and can hardly be as old is Chazy. Beaverfoot-Brisco Formations These two formations are found throughout the Stanford range in the indermere area. They consist of thick to moderately thin-bedded crystalline ana seii-crystalline limestones. The beds are the strati^raphical equivalent of tne Halysitee beds of the '^ield area. The Beaverf^ot are of Richmond a.^re and the Brisco of Silurian, bat in the inoermere area they are tran-itiun! aid it is i vencible to make mi accurate div'sion. Ordivician of the Main C.P.h.Area 1 Ooodsir For mation This formation is ^ell exposed in ,..'t. Goodsir, where it is 6,040 feet thick. It lies confor ably on the Ottertail and consists a1 the base of 3, J00 feet of alterna-ting hard and soft bands of argillaceous, calcareous and siliceous eMales. The ut-per part of the formation consists of banded cherts, eherty limestones and dolomites, thin-bedded ana very dense. The beds in this series recome very highly sheared in the Beaverfjot valley and the range to the vest. ll Allan, J.A. deol.Su v.Can. 'luiac Book No.8. Pt.S. p.180* Glenoale (Graptolite) Shales These shales consist of black, carbonaceous and brown, fissile shales at the top, underlain by grey shales which grade into the underlying Coodsir formation. The thlcness of this formation varies, and the lower contact is ill-defined, hot a thickness of at least 1,700 feet is represented, in which are found faunas of Beekmantown and uhazy age. Olenoxle shales occur as two infolded bands in the Beaverfoot ran^e. 1 Ordivician Rocks of the Robson Peak Area Koison limestones The Kobson formation is considered to extend from the summit of ^obson Peak some 3,0)0 feet down. "his thickness was estimated by a view frum Billing's Butte. The rocks are light-grey, thin-bedded limestones, forming massive strata on eliff exposures. The formation lies conformably on the Upper Cambrian. 2 Burling disagrees with Yalcott in most particulars regarding all formations of this area and especially in res-pect of the Robson. 1. '.alcott, C.D. Smithsonian Misc.Colls.Vol.57.No.12.p.331 2. Burling, L.D. Bull.3eol.Soc.Am. Vol.34. 1923. p.727 -73-SILUKIAN Silurian strata of Clinton age, consisting mainly of limestones more than 1,0)0 feet thick, have been found in the mountains bordering the Rocky mountain trench south of the Kicking Horse river. Beds of this age appear to be absent farther east. They may continue northward along the western ranges of the Rocky mountains. Silurian of the Windermere Area Brisco Formation This formation has already been described under the Ordivician of this area. 1 Silurian of the C.P.R.Area Halysites Beds (Brisco Formation) "These beds are the stratipraphic equivalent of the limestone part of the Halysites bods of McConneH and Allan. Burling first referred to these beds as being of Richmond age, and in 1922 gave the name Beaverfoot to them. '.alcott has given the name Brisco to the Silurian beds, but in the Sinclair Canyon section, as reported by Kalcott, and in the Windermere mrp area the Richmond is transitional into the Silurian."2 The Halysites beds consist chiefly of dolomitic limestone and white quartzite. ThiB formation lies 1. Allan, J.A. Ceol.Surv.Uan Guidf Book Mo.8. Pt.2. p.181 2. Valker, J.F. Idem. Mem.148. 1926. p.32 -74-conformably upon the Graptolite beds. The character of the rock sharply distinguishes it from the older strata. The formation is terminated above by a fault contact or by an erosion Burface. A measured section gave 1,850 feet. The white quartzite is over 900 feet thick. It is infolded with the Graptolite beds in the Beaverfoot range. Some of the beds of dolomitic limestone are highly fossillferous; corals are most abundant, but crinoids, brachipods and gastropods are also present. This is the youngest formation exposed to the west of the Continental Divide, along this section of the Rocky Mountains. DEVONIAN "In Devonian time, perhaps after a general with-drawal of the sea, the whole eastern Cordilleran region was again submerged, and in this sea, which presumably extended far to the east, were deposited calcareous strata attaining in places a thichness of several thousand feet. The Devonian beds have been recognised at intervals from the International Boundary line in the south to the Alaska-Yukon boundary in the north, but nowhere have either the earliest or the latest Devonian faunas been found, and as in the case of the earlier Paleozoic hori-zons, the western edge of the basin of deposition seems to have lain not far west of the edpe of the Rocky Mountains. The Devonian beds in the south and in various places in the eastern part of the Rocky Mountains rest on late Pre-Cambrian or Cambrian strata, but in the western part of the Rocky Mountains they in places succeed Silurian beds."! 1. Young, G.A. Geol.Surv.Can.Geology & Economic Minerals of Canada, 1926, p.151 -75-1 Devonian of the Galton Kan^e At the eastern edge of the drift covered Tobacco Plains a block of Devonian limestone has been faulted down into contact with the Gateway formation. The main fault which limits the block on the east can be rather sharply located, the strikes of the limestone and ihe Gateway metargilllte being nearly at rirht angles. ^he apparent tbic^nees of the strata is about 1,600 feet. Of this ZOO feet represent dolomitic quartzite, occurring at ihe base of the section. Fossils froi the limestone indicate it to be of Devonian a^e. The quartzite contains ¡o fossils but is probably of Devonian age also. The greater part of the limestone can be correlated with the Jefferson limestone of Montana. Devonian and MiHsi-sippirmJLimestones of the tacDoni ld Ran^e^ Great displacements on the western side of the Flathead trough have cropped Devonian and ^i.siasipplan lime-stones down into contact with the oldest te thers of ihe Galton Series. The result of this faulting is that n long slab-lire block of Altyn, Hefty and MncDonald beds is bounded on both sides by Mississippian linestone. "he younger fossiliferous 3. Daly, R.A. Geol.Surv.Can. Mem.38. 1912. p.110 2. Idem Idem Idem. p.113 -76-limestones form two masses seuarated by the slab and may be referred to as the western and eastern blocks. The western block Is nol well exposed. The lime-stone is dark, bluish-grey, massive, rarely shewing strati-fication planes. Fossils seem to indicate its a?e as Upper Mississippian. The eastern block is composed of both Devonian and Missi^sippian limestones, greatly broken by step-faults, with down-throw to the east. The combined thickness of the Devonian and Missi sippian is probably well over 1,010 feet. 1 Devono-Carboniferous of the Crowsnest Area The great Levono-Carooniferous series of rocks are found widespread in the Crowsnest Pass area, where they have not as yet been separated. Here they form the main range of the Rocky Mountains separating tbe Crowsnest coal areas of British Columbia from those of Alberta, also a minor range, the Yisukishak or Erickson ridge, near Michel, and the high mountains of the MacDonald range west of the Flathead valley. The rocks consist largely of evenly-bedded, compact, grey limestone, and lie conformably under the ^ernie shales, The unper portion is of a light coloured quartzite and sili-ceous limestone. It may probably be correlated w!th the Rocky Mountain quartzile at Banff. ^ section, measured at the Crowsnest station, gives a thiciness of about 10,000 feet with the base not exposed. 1. Rose, B. Ceol.Surv.uan. Sum.Rep. 1615, 1916, 1H7. -77-Contact with the underlying Middle Cambrian is known only in the vicinity of North Kootenay Pass. The rock here overlying the Cambrian is a massive, unfossiliferous limestone, and above this the first fossils are Devonian. The fossils toward the top of the series are all of Carboniferous age. 1 In the Flathead area, Mackenzie divides the rocks into a Devono-Carbonifarous and a Carboniferous formation. The thickness of the former he places at 3,000 feet. Devonian at Klko Devonian limestones, probably of Jefferson are, rest with a disconformity on tbe underlying Elko of the Cambrian. The staple rock is a massive, dark-grey lire-stone, weathering a whitish-grey colour. The thic ness is 300 feet. Devonian Rocks in the O.P.R.Area 3 Ghost iHver Formation Between the Cambrian and the hevonlan of the C.P.R. section is a formation of 300 feet of thin-bedded and shaly, buff-coloured, magnesium limestone lying conformably between the superjacent Devonian beds and the Middle Cambrian bees beneath. Lack of fossils prevent its assignment of a 1. Mackenzie, J.D. Geol.Surv.Can. Mem.87. 1916. p.15 2. Schofield, S.J. Idem. Mem.76. 1915. p.48 3. Shimer, H.h. Idem. ^ius.Bull.No.42. p. 2 weat, and in the Devonian. t Minnewanka Formation Two Devonian formations were originally recognised the C^.R.section, the Intermediate limestone and the Î 2 3 Lewer Banff limestone of McConnell, Saimer, and Allan. A - . . r: Kindle gsoapsd the two formations into one and substituted the name Banff limestone and dolomite. His chief reason ^ for the re-naming and re-grouping of these formations was because he regarded the dolomitization aa being largely of * S anbaeqaent or secondary origin. Shimer later changed the name to Minnewanka. That nomenclature and classification t '. . - ' - -have been accepted here as appearing to be the most satisfactory. The Minnewanka limestone and fauna are found in the front ranges north Urom the Bow river to the Athabasca. . ..S -S)--;'.' - ' ' The lower 1,000 feet consist of thin-bedded magneaian limeBtones; the upper 1,900 feet of massive, grey limestones with shale interbedded. The whole formation ia regarded as being approximate ly the equivalent of the Jefferson limeatone of Montana. 1. McConnell, B.G. Geol.Surv.Can.An.Rep. 1886. p.l5-D 2. Shimer, H.W. Bull.Geol.Soo.Am. Vol.24. 1913. p.234 3. 411*9, J.A. Geol.Surv.Can. Sum.Rep. 1912. p.168 4. g&a%le,Z.M. Pan-Am.Geologist. Vol.42. 1924.pp.113-124 6. Shimer. H.W. Ball. Geol.8oc.Am. Vol.24. 1913. p.234. i. - 7 9 -1 Devonian of Roche Mjette s The Devonian at Roche Miette is constituted of heavily-bedded limestones. It is similar to the Devonian of the Bow River area. CARBONIFEROUS "The Devonian beds of the Rocky mountains in many localities are followed by Carboniferous strata ranging in age from Mississippian to late Pennsylvanian. In districts about Banff, the earboniferous measures have a total thickness of nearly 5,000 feet and consist of a lower argillaceous member, a middle limestone member and an upper sandy member.^ The whole succession is conformable, but sudden changes in the character uf the fossil faunas indicate temporary withdrawals of the sea. The upper sandstone or quartzitic horizon appears to occur as far south as the International Boundary and presumably this persistent horizon with the underlying limestones extends northward through the whole length of the Rocky Mountains 4 Carboniferous of the Flathead Area Carboniferous rocks underlie a considerable area in the district about the Flathead river. Their thickness is about 2,000 feet. The rocks are wholly limestones of various kinds. They are mostly light weathering, grey to black rocks, the latter owing their colouring to bituminous matter, which also gives them a strongly foetid odour when struck. They are 1. Dowling, D.B. Geol.Surv.Can. Sum.Rep. 1911. p.206 2. Shimer has since placed this member in the Permian. 3. Young, G.A. Geol.& Econ.Minerals of Can. 1926. p.153 4. Mackenzie, J.D. Geol.Surv.Can. Mem.87. 1916. p.16 -80-found as flaggy, thin-bedded and massive layers, with platy parting parallel to the stratification. The formation lies conformably on the Devono-Carboniferous, and is set off from the formation above by a disconformity. The fossil content, which contains, among other genera, Productus, Feneslella, Spirifer, Tripophyllum, Ptilopora, Batostomella and Derbya, makes it evident that the formations range from upper Missi^sippian to lower Pennsylvanian in age. 1 Carboniferous of the C.P.R.Section The Carboniferous in this section is found in the mountains in the vicinity of Lake Uinnewanka. Banff Formation (Lower Banff Shale) This formation is of Mississippian age and rests conformably on the Minnewanka limestone. It is predominantly a dark grey to black calcareous shale, weathering brownish, which changes at the top to a shaly limestone difficult to distinguish from the overlying limestones. The thickness is 1,200 feet. Bundle Formation (Upper Banff Limestone) 2 For the Upper Banff limestone Kindle proposes the 3 name Rundle ibrmation. Shimer uses the sane term but divides 1. Shiner, H.V.. Geol.Surv.Oan.Mus.Bull.ho.42. p.6 2. Kindle, E.M. Pan-Am.Geologist. Vol.42. 1924. p.123 3. Shimer, H.Y.. Geol.Surv.Can. Mus.Bull. No.42. p.2 ^the Randle into a Pennsylvanian upper two-thirds and a !: Hls8iBsippian lower third. He describes the beds as thin-tedded light to dark grey limestones, becoming more shaly downwards until they merge into the Banff shales. The formation is over 2,300 feet thick and has good exposures in the Sawback and Cascade ranges. 1 Carboniferous at Roche Miette Carboniferous limestones, sandstones end shales in thick beds are found in the Roche Miette area. The thickness is about 3,000 feet. The formation may be regarded as the equivalent of the Bundle and Banff formations at Lake Minnewanka. PERMIAN Permian beds are known in the area about Lake Minnewanka,and north at Roche ^lette Bowling describes a formation as Triassic-Pernian. It is probable that the 2 white quartzitic rock mentioned by Young as extending southward to the International Boundary as upper Carboni-ferous is Permian. If this is so, Permian rocks extend the entire length of the Rocky system on the eastern part. 1. Bowling, D.B. Geol.Surv.Can. Sum.Rep. 1911. p.206 2. Geol.& Been.Minerals of Can. Geol.Surv.Can. 1926. p.153 * * ' ^ Rocky Mountain quartzite 1 Allan classes this formation as Pennsylvanian; 2 Shiaar, on faunal evidence, places it in the Permian. The thickness of this formation in the Sawback Range is 800 feet. It thickens rapidly to the east and 1,200 feet are exposed at Lake Minnewanka. The formation is an alternation of light grey quartzite and light-grey limestone, the former predominating in the upper part, the latter In the lower, where it merges imperceptibly with the Rundle limestone. The uppermost 50 feet contain considerable conglomerate with rounded quartzite and calcareous pebbles up to 2 inches in diameter. MESOZOIC TRIASSIC "In the Banff district, the Carboniferous (Permian) beds are overlain disconformably by about 15,000 feet of sandstone and shale of marine origin and Triassic ago. Beds of this ape may extend throughout the length of the Rocky mountains. They have been recognised along the ^eace and Liard rivers and occur in the western ranges of the Mackenzie mountains. In these various areas the Triassic beds, though deposited after an interval of emergence from the sea, are essentially ^ conformable with the underlying Paleozoic strata." 1. Allan, J.A. Geol.Surv.Can. Guide Book No.8. Pt.2. p.183 2. Shimer, H.A. Idem. Mus.Bull. No.42. 1926. p.6 3. Young, G.A. Geol.& Econ.Minerals of Can. Geol.Surv.Can. 1926. p.153 , "J *' - _ . .* ' . ^ ^ Triassic of Flathead Area Rocks tentatively assigned to the Triassic epoch are the aarf&ce formation of a considerable area in the western portion of the district about the Flathead river. The thickness is about 2,500 feet. The formation is strikingly homogeneous wherever it has been observed. It consists throughout of white or pale gray, very fine, even compact sandstone. there unweathered, the rock is pale grey, with a sub-vitreous lustre, simulating a qaartzite. Though good exposures showing contact with formations above and below are not known, structural relations indicate a disconformity belor and conformity with the Femie above. The formation is barren of fossils and on strati-graphical grounds is placed in the Triaseic. Triassic in Banff Area Spray River Formation 2 The Upper Banff shale which Allan places in the 3 4-Permlan, Kindle and Shimer place in the Triassic and call the Spray River formation. This is an alternation of heavy-bedded, light grey, calcareous arenaceous shales. At . - - ' . ^ 1*1 MacKenzie, J.D. 5eol.Surv.Can. Hem.87. 1916. p.*20 Allan, J.A. Geol.Surv. Can.Guide Book No.8. Pt.2. p.183 3. Kindle. E.M. Pan-Am.Geologist. Vol.42. 1924. p.115 4. Shimer, H.A. Geol.Surv.Uan. Hus.Bull. No.42. 1926. p.2 areqaant intervals throughout the entire thickness occur many Fippla marks, mud flows, minor crossbeaaing and mud cracks. The contact with the fbrmations above and below is conformable. Good exposures occur at Rundle mountain, where a thickness of about 1,400 feet has been found. Area at Roche ^lette Triassic rocks at Roche Alette have already been t described under Permian. 1 McConnell recognised Triassic rocks on the Peace and Hard on reconnaissances through those areas. JURASSIC From the 49th parallel northward to the Athabasca river, and probably farther, the Triassic, or where they are absent, late Paleozoic strata, are succeeded by the dark marina shales of the Femie formation of Jurassic age. The Femie beds in places rest conformably on the underlying strata, but the presence in places, of a few feet of basal conglomerate holding fragments of Paleozoic strata indicates that, preceding Femie time, considerable areas lay above the sea, and were subjected to erosion. The ^ernie measures in the eastern ranges of the Rooky mountains are less than 1,000 feet thick, but near the International Boundary increase in thickness to the west, ^here in places they are more than 1, McConnell, R.B. Geol.Surv.Can. An.Rep. Vol.7. 1894.p.31-C Idem Vol.4. I888.p.44-D 3^000 feet thick. The *emie appears to grade into the overlying Kootenay. The composition of the thin basal conglomerate at the base of the ^ernie indicates that the strata of the land mass to the west were sufficiently domed or folded to permit agents of erosion attacking different formations. Workers in the Fernie have correlated formations to such good effect that one ns^ te applies to this formation throughout the great areas it covers in the Rockies. This has been aided by the presence of the Kootenay above with Its coal measures. 1 Jurassic in the Crowsnest Pass Area Fernie Formation The Fernie formation is found evenly distributed throughout the Cyowsnest Bass area, and commonly occurs in the valleys and basinr of this district. The formation consists in the main of shale contain-ing Jurassic fossils; brown-black, grey-black, thinly lamina-ted and fissile shales predominate, and a persistent band of quartzite, 50 to 100 feet thick, is found at the base. At the top, the Fernie becomes arenaceous, and alternating bands of brownish sandstone and shale lead up to a massive, coarse-grained sandstone above which are plant remains and eoal seams. The base of this heavy sandstone is used as a dividing line between the ^ernie shales and the overlying Kootenay formation. H Rose, B. 3eol.3urv.Can. Sum.Rep.1917. p.30 ; f^ ^ e ^em le is o w 3,000 feet thick in the Elk ^ylwr valley hut thins toward the east where a maximum thickness of 700 to 800 feet occurs in the Crowsnest coal areas on the Alberta slope of the mountains. Jarassio in the Banff Area y * ' , ' -Femie Formation The Femie holds much the same character all through the Rocky mountains. In the Banff area it consists of black and dark brown siliceous shales thinly laminated. West of Banff its distribution is limited, lying on the Spray river formation. East of &anff, and on the north side of the Cascade trough, it forma a band about 1,500 feet thick. p Jurassic at Roche Mlette Femie Shales Typical Femie shales with sandstones Interbedded are found in the Roche Mlette area. CRETACEOUS "The Femie strata appear to-grade into the over-lying Kootenay formation, which is non-marine in origin, holds thick coal seams and consists largely of alternations ofcrossbedded sandstones * and dark shales. The Kootenay formation , TI Allan, J.A. Geol.Surv.Oan. Ouide Book No.8. Pt.2. p.184 2. Bowling, D.B. Geol.Surv.Oan. Sum.Rep. 1911. p.206 -87-decreases in thickness from west to east; the greatest thickness is 5,000 feet. The coal bearing Kootenay measures are preserved in places along the whole length of the Rocky mountains, hut in some localities are separa-ted from the F$mie beds by a thick series of sediments. The Kootenay strata are considered to be of Lower Cretaceous age and to be separated by a considerable time interval from the under-lying marine Jurassic, despite the seeming gradation of one formation into the other J The marked increase in thickness, in a westward direction, of both the ^ernie and Kootenay beds, indicates that the source of the clastic materials composing these formations lay to the west, Sandstones and conglomerates in the Kootenay lead to the general conclusion that, commencing in late Jurassic time, the part of the Cordillera lying west of the Rocky mountains was withdrawn from the sea and was subjected to differential movements of gradually increasing intensity, so that the region affected assumed a mountainous character. "Along the eastern border of the Cordilleras region the deposition of sediments was a con-tinuous process from the Kootenay period in later Lower Cretaceous time, to the close of the Upper . , Cretaceous, and the strata of this long interval are displayed throughout the length of the Rocky mountains. In the southern p-.rt of these mountains, the coal-bearing Kootenay beds are overlain by the Blairmore formation consisting of interbedded sandstones'and shales with bands of conglomerate and having a thickness of 2,000 to 3,000 feet, increasing in amount westward. The upper part of this formation may be of Upper Cretaceous age. Along the Crowsnest pass, the Blairmore is overlain by bedded tuffs and agglomerates which attain a maximum thickness of 1,100 feet. These beds are found within a limited area, outside of which the BlPlrmore is overlain by marine shales of Colorado age. These beds, in places 3,000 feet or more thick, are succeeded upwards by the Allison beds of fresh and brackish-water origin, possibly corresponding to the ^elly River beds of the plains region to the east ..The thickness of the Cretaceous strata is 20,000 feet or more, and this great volume of clastic material, spreading far to the east, was derived from the then rugged region/ to the west."l l" Young, G.A. Geol.& Econ.Minerals of Oan^Gepl.Sury.Can. The Cretaceous of the Crownest Pass Area -68-1 Kootenay Formation The kootenay is found widespread in the Crowsnest region, both in Alberta and British Columbia. The formation is made up of alternating sandstones, shales and coal seams with considerable conglomerate toward the top of the section. Massive, coarse-grained and cross-bedded, grey sandstones stand out prominently. The formation is sab-adrial in origin as is shown by the character of the sediments, coarse, croBs-beddec and ripple-acrked sandstones, fossil l?nd plants and shales associated with coal seams. It is difficult to designate an upper limit of the formation as the strata above is much the same except that the sand-stones are coarser and there are a number of conglomerate bands. A section on the Elk river escarpment north of Morrissey shows 216 feet of coal in 3,300 feet of strala. T6 the north, in the Upper Elk valley coal basin, the Kootenay reaches a thickness of 3,600 feet. In the Flsthead valley there are about 1,100 feet of strata, and at Plairmore, Alberta, the thickness has diminished^ to 450 feet. 1. Rose, B. Geol.Surv.Can. Sum.Rep. 1917. p.30-C 105 Blairmore Formation The Blairmore formation is confined in its dis-tribution to the eastern part of the Crowanest pass area ana mainly to Alberta. Here it overlies the Kootenay without any evidence of unconformity unless the conglomerate at the top of the Kootenay should mark a short cessation of deposition. The formation consists essentially of sandstones and conglomerate varying grently in colour and texture with one thin bed of bluish, shaly limestone towards the middle of the series which is very persistent in the Blairmore area. Marked differp-nceBin thicknesses take place in comparatively short distances. In the Hairmor^ area 2,100 feet are represented. 2 Elk Conglomerates and Flathead Beds In the districts about the headwaters of the Flathead river and on some of the higher mountains east of the Klk river, recks of Blairmore age are found and are known as the Llk conglomerates and ^'lethead begs. They are formed by the gradation of the Kootenay strata upward into conglomerates, coarse sandstones and shales. These beds have been called the Elk conglomerates to distinguish them from the less conglomeratic strata below 1. Leaoh, V.K. Ceol.Surv.Can. Sum.Rep. 1911. p.195 2. Rose, B. Idem. Idem. p.31-C -90-and above. The rocks above the Elk conglomerates are mostly green, and reddish shales and sandy shales interbedded with sandstones and some conglomerates. It is this upper part that is known as the Flathead beds. The combined thickness of the two formations is 6,500 feet. 1 Benton (Colorado) Formation The Crowsnest volcanics rest on the Blairmore forma-tion. Conformably on these is the Benton formation. It occurs widely in the Blairmore area. The rocks are almost wholly dark grey to black fissile clay shales. Near the top of the lower third of the measures occurs a bed of very hard, fine to medium grained qaartzitic sandstone, ordinarily from 10 to 30 feet thiol , bat in the vicinity of North Kcotenay pass 150 feet. Above this band the measures are mora arenaceous. The thickness of the Benton averages 2,000 feet, in places reaching 3,009 feet. 2 Allison (Belly River) Formation The Allison beds lie conformably on the Benton shales and stratigraphlcally are the youngest of the bed rock forma-tions of the Blairmore area except that "in certain districts it is overlain by an aeeembla-ie of shales and sandstones, in 1. Leach, t .Y.. Geol.Surv.Can. Bum.Rep.1611. p.197 "* A-Idem ' Idem Idem p.198 -91-10,000 feet thick, whose higher beds are presumably 1 very late Upper Cretaceous age." In the Alliaon, sand-atoaee predominate, mostly white or light grey, sometimes pale green, massive or with shaly structure, often laminated and croasbeddcd and rather soft. Some considerable beds of dark gray shales occur, also several beds of light green, plastic shales. The top of these beds is not known, but about 2,000 feet are exposed on the west branch of the South Fork river. 2 Cretaceous in the Banff Area Lo-.er Ribboned Sandstone The Cretaceous beds are exposed along the eastern base of Cascade mountain. The Lower Ribboned sandstone consists of alternating bands of brown-weathering sandstone and shale. This formation follows the bottom of the Cascade trough and is exposed on the road between Bankhead and the west end of Lake Minnewanka. The beds here are about 1,000 feet thick. Kootenay The Xootenay here is similar to the corresponding formation described above. It consists of 2,800 feet of - sandstone and shale enclosing several workable seams of coal. Particularly good coal measures occur at Oanmore and a considerably high.grade bituminous coal has been mined at t 2 BaaXhead. Upper Ribboned Sandstone This formation consists of thin-bedded sandstones and shales. It is exposed at the eastern base of Cascade aosntain. The beds are wedged between the coal measures below and a thrust plane above. Some of the uppermost Cretaceous beds were planed away when the older beds were thrust over them. There are about 55C feet of beds exposed in Cascade mountain, but tnis formation becomes thicker to the north-west and south-e&st of this section. Cretaceous in Northern Areas In the -aoche ^ ictte area the typical coal-bearing Kootenay rocks of the mountains and foothills occur. The top of the formation is not present. Cretaceous beds -probably occur in the little known 1 Peace and Liard sections of the hocky mountains. - MeConnell has recognised Mesozoic rocks on both slopes of the mountains in the Liard river area. TERTIARY 2 Kishenena Formation of the ¿lathead Area The Kishenena formation underlies a large portion of the ^lathead trough. It is known to extend from the 49th parallel northward beyond Beryl lakes. 1*7—MuCunnell, H.G.- Geot.Sui-u.Can. An.iarpiVul.4.1M8.p.44-D 2. MacKenzie, J.D. iaent Mem.87. 1916. p.31 Little information is available in regard to the thickness of these beds, They apparently reach a thickness wf 1,600 feet and may be much thicker. - These sediments may be divided into t^o facies. The iggwt consists of coarse gravels ana ^ands 3ith seme clay, is eraee-bedded and lenticular in characbcr and contains many thin seams of lignite. The second facias is mj.de up of partially consolidated, v.,ry fine-grained, evenly-laminated, feasiliferous, freshrat^r linostones, alternating with fine clay beds and very thin aeaus^oi' lignite. Fossil eviaence, thouginot absolute, at least strongly supports the conclusion that the Rishenena is of 1 Eocene age. ^illi$ nolds th^t those beds are freshwater J& ke sediments. 'Tit ¡"i^T.'.'H The description given in Guide Book 8 of Pleistocene and Recent oeooaite of the C.P.R.area is typical of ail such deposits in the Rocky mountains. ^The unconsolidated material is represented by three types of Jeposits as ¿ho^n in the section. The fluviatlle and. lacustrine deposing a,i„p.;.-..r in terraces abouu the sides of the larger valleys, while the former also floors the broad plains of the main streams such as the Bow, the Kicking Horse, the Bcaverfcot and the Yoho. "Glacial till veneers the more gradual dlopes of - the various ranges, to an elevation ab least 9,000 feet above sea level. 1* ¿illis, B. Geol.Soc.Am. Vol.13. 1902. p.327 /Allan, J.A. Oeol.Surv.Can. Guide Book 8. Pt.2. p*186* 93*.(Insert) ' T*rtia&v Rocks in the Finlay Area. , Three small areas of unmetamorphosed Tertiary ^(^aants acaur in the ^cky Mountain trench in the T I B M ^ area. They extend from the mouth of the Ingetilka rivar north to the mouth of the Fox and probably beyond* i ; The rooks aonslst of coarse conglomerate and sandstones, being clearly derived from the underlying formation. Plant remains determine their age as Tertiary* Dolmaga, V., Gaol. Surv. Can., Sum* Rapt. Part A. 1927. IGHEOUS ROCKS Igneous rooks are not comaon in the Rooky S#aatain region, though there is a possibility that this may t* aooonntea for by the great thickness of the sediments and the comparative youthfulnoss of the system. Igneous rocks are limited to three lava flo^s throe Intrusives. 1 FuroQ i.l Lavas The i-urceil lnv..s have been traced from south-east of Altyn, Montana and from heights overlooking ^atorton Lake all the way to the eaet--rn summits of thu lurcell range on the International Boundary. Summary of Lithoiogical Features Galton range 60' amygdaloid 40' coarse breccia 200' amygdaloid ",'ith phanocrysta 90* non-vesicular porphyry 390* Clarke range 260' amygdaloid Total lava 260' _-ykeu and sills cutting siyeh immediately belo Lewis range 35' amygdaloid in Shappard 40' amygdaloid in Kintla 18' massive amygda-loid flow 40' repy lava passing belc.-- Into plllot; lava Total lava 58'.Dykes and sills cutting Siyah immediately below 1* Daly, R. Geol,Surv.Can. Mem.38. 1912. pp.207-220 the Hvingatone xange to the east and the main range of the g^g&y mimntaina to the vest. Good exposures occur near the ttppaa of Blairmore and Coleman. The contact between Biairmore measures and the vol-sanie rooks is a gradational one. Yhe beds often pass gradually from greenish sanéatenos and shales into well stratified tufaoeoue rocks and exact contact ear. often not be placed at any ^iven horizon. ^ gradational relation-ship occurs aiso between the volcantes - ad the Benton aleve. The Cronsnost rocks are finer and thinner bedded to-ard the top and the transition becomes ísifíievlt of detection. "At the time the deposition of the Cronrsneat volca:dcs begun, the area the no;' cover i^ as Occupied b¿ a shallor sea probably of fresh .vater, containing lo..' marshy lands. rhe.-e is no r cognised evjdence to shov whether the ?ents emptied into the air or -ere submarine; any cenes thai, ,.¡ay have b en built up above sea level would naturally be destroyed during the incursions of the sea in Beaton time. thickne&s of bhe deposits in relation tu tr.eir lateral extent seems to indícate that the beds aro due to the simultaneous effect of several small volcanoes of moderate activity, rather tha.< to the action of one iarpe vent. The eruptions ;?ere of the explosive type, unaccompanied by flovs ey^e, t very locally, and toak place in continual sequence during a rela-tively short period oí time. By far the greater part of the ejected material fell into the ¿ea and there was eepoeiúed in mo e or less well stratified beds."A The Jrovsnost volcanics con.-iet of franmental atratified pyroclastic rocks which exhibit sevarai primary types occurring as fragments. These are, in order of abundance, trachytes, blairmorites and latitas. The MacEo! aie, J.jj. &ool.jurv.jan. ^us.¿ull.B0.4* p.13 g trachytes are soda-rich varieties. Aegerine-augite trachyte ^âBBé meianite trachyte havé been recognised aa aeparate ^ types. %he blairmoritea are unusual rocks, ultra alkaline, teda-rich porphyries, characterised by primary analcite in large qnantitiea up to 71%. The primary typea have been altered only slightly. The fragmentai volcanic rocks conaiat of both mineral and rock fragments of varying aizes and associationa characterised by minerals typical of alkaline rocks, ortho-elaae, aanidine, soda orthoclase, aegerine-augite, analcite, ^ melanite, titanite, etc. The maximum thickness of this formation is 1,180 feet, measured near Crowsnest mountain. A constant decrease in thickness ia shown from this vicinity toward the north, south, and mere rapidly, toward the east. The overthrust-ing of the weat conceals outcrops there. Jurassic Tuffs "In the quarry section at Blalrmore and on the Castle river is a bed of green tuff 50 feet wide In the latter section. This is the earliest appearance of volcanic material in the Mesosolo -sediments of the.Northern Rocky mountain system." It corresponde to the great flood of volcanic rocks which occur in Western British Columbia In the Jurassic. 1. BCLeam, P.H. Geol.Surv.Can. Sum.Rep. 1915. p.Ill \ s ff; Ice River Intrusive The Ice River intrusive is the largest intrusive body in the Rocky mountains. It is located on the Ice River and is exposed for about 12 square miles. Its form is that of an asymmetrical laccolith with a stock-like conduit. The igneous mass as a whole is alkaline. The various types together with their transitional phases form a complete aeries between two widely separated extremes. The one end of the series which is most highly alkaline is repre-sented by a light-grey or greenish-grey nepheline syenite. In this normal type the relative amounts of feldspar vary, and with the addition of sodalite the rock becomes a light, bluish-grey, sodalite nephelite. At the other end of the aeries is a jacnpiranglte. This rock is black and lacks all light coloured minerals. The distribution of this type is not as well defined in the fieid as the nepheline syenite and it passes into pyroxenite when pyroxene becomes the essential and practically the only mineral present. A type intermediate between these two extremes is an ijolite which is mad* up essentially of nephelite and aegirite-augite. There is a marked contrast in the fie^d between these three main types, bat when the numerous transitional phases are included, no sharp line of division can be made and the complex affords a continuous petrographic series. 1. Allan, J .A. Gaol.Surv.Can. Mem.55. p.105-195. sgj^ The age of the intrusive Is believed to be poat-erataeeoaa aa determined by structural and correlation '* B' * g'. Cross River Intrusive On the Cross river are "numerous large masses of greeniah-grey diorite (Y) somewhat resembling the intrusive 0% Ice river bat apparently not, like that, a nepheline syenite. They have derived from an intrusion of the same material.......Associated with and cutting the diorite are 1 quartz veins carrying copper pyrite." Bull River Intrusive "North of the Bull river a low, isolated hill was found to be composed of a remarkable crystalline rock which is evidently intrusive. It is chiefly composed of well-formed orthoclase feldspar crystals which are pinkish in colour and in some cases nearly an inch in length It may be regarded as a variety of quartz porphyry in which the quartz is, however, observable under the microscope only."2 1. Dawaan, G.M. 9eol.Surv.0an. An.Rep.No.1. 1085. p.ll6-B a. Idem Idem Idem P.151-B -100-CHAFTER 3y. TEE STRUCTURE OF THE ROM? MOUNTAINS mTBODUCTION The disturbance ^ hich uplifted the Rocky Mountains was one last of the great tectonic movements of the Cordillera. The cause of the mqrement is related tp the causes for all mountain building and is a pro-blem which is still fsr from solution. The theory of a shrinking or com-pacting earth is one of the ;aore plausible theories. In such a case the entire globe is effected with a consequent deformation of shell, fhis need not rule out the factor of ieostatic balance but leaves it as a factor determining where deformation shall be most expressed and when it «hall oeeur. Thocs parts of the earth which react to the greatest extent r-e the heavier oceanic segments. They are depressed much oore than co. ^ inent-al segments and to such a degree that continental segments are forced up or at leaw^in greater relief than before movement began. According to this theory, the greatest application of the force would occur along the edgea of the continents with deformation in those regions. Such a theory suggest the permanence of continents and of the sites of mountain ranges. Thus might have risen the Rocky Mountains. One objection to this theory is that the Rockies are found far inland. 3ut it is known that de-foliation of an area increases its resisting power. The areas between the Rocky Mountains and the coast were already considerably deformed and yield-ed to pressures lea* easily than the Sastem Oeosyncllne. waaawe aCBaaBarim, R.T. Jour. Geology, vol. SRX11. No. 7. pp. 545 - 574. —1Q1?* This explanation does not rule out the possibility of rising isogeother-mal lines having had some share in uplift of the sediments into a great mountain system* Chsmberlin ^  applies the wedge theory of disatrophism to the up-lift of continents and mountain systems. Hence he explains the Rooky Mountains by a vigorously contracting earth breaking the area in the form of a great wedge^abeve the level previously assumed. This explan-ation would involve overthrust faulting on both eastern and western edges-. Though such exists on the eastern side, his contention that overthrusting is also a feature of the western edge receives the support of but a few of the investigators of that area. The general features of Rocky Mountain etructure are similar in the greater part of the mountains. The whole system forms a great syncliaorium* The eastern edge is marks;! from thj Peace River to the 49th parallel by an almost continuous overthrust. The eastern ranges are the result of thrust faulting which raised great blocks ?rith sharp east-a m escarpments and gently-dipping western slopes. The central ranges are formed of gently-folded sediments cut by a few great normal faults. The western ranges are marked by close and overturned folds and Many great faults. The Rocky Mountain Trench is partly a structural feature and partly the result of erosion. 2 StuMtgra af the Southemrraaat Rockies MeeKeazie divides the section of the Rockies, lying between the 49th pay Hal and the Crowaneat Pass district into three structural areas, a western, a central, and an eastern. 1. Chanaarlln, R.T. Jaar* Geology Vol.XXXlll No.e, pp. 755 - 79S* 2* MaeKaazie, J.9* Royal Soc.Csn., Proc. & Trans.1922.Pt.lV.r.97-130. Western Area This area Mas between the Elk and the Kootenay Rivera on the weat ami the Flathead River on the east. In its southern part it is characterized by hcmoclinal fault blocks separated by large normal faults. Northward, folding predeminatea over normal faulting. Central Area At the 49th parallel the central structural area is a great synclima of pre-Cambriac strata, l^is structure holds north to the vic-inity af Norta io^taaay Pass. In this distance it is separated from the area to the wast by a great normal fault or zone of faults along the east side of the yiathead Valley. These faults have a downthrow to the west. The area is narrowed towards the Crowsnest Pass by the western swing of the Lewie overthrust. Eastern Straataral Area The third and eastern area consists of the foothills and mount-ains of western Alberta adjacent to the Crowsnest 1 ass. Here the rocks are Cretaceous with the exception of soma uevono-Carboniferous strata in the Pasa. Structurally it is characterized by numerous, nearly parallel, reverse, strike faults, of great lengths and unusual steepness, ith them are associated strong folds. The reverse faults of the eastern area are notable in many re-spects. They are very long and generally parallel the strike of the rocks. Unusually little disturbance and breakage has taken place in their part-ing aarfaeea and no preliminary folding is indicated. On the whole, they hawe a very high angle of dip, and their strike is quite straight. Twenty-two faults near Blairmore give an average dip of over 70°. They afford good lllaatrations of the lH&ricate structure described by Cadell. The Lewis Overthrust -103-A large part of the Clarke Range haa been bodily thrust over younger strata to the east so that its massive Beltlan rocks rest on Cretaceous* This great thrust haa been named the Lewis Overthrust. oil borings near Waterton Lake disclose Cretaceous shales under 1,500 feet of siliceous dolomite of the Beltian, thus giving the thrust a known width of 15 miles, and if the oil and gas of the Flathead Valley eman-ate from Cretaceous beds below, the thrust would have a width of 40 miles representing the operation of a gigantic force by which the entire Clarke Range was torn from ita foundations and thrust for a great distance. Longitudinally, the thrust extends from the Boundary to latitude o 50 , a distance of 65 milea, and la thought to continue almoat to the Peace River. It Ilea at the base of the front ranges north to North Kootenay Paas where it passes behind the Livingstone Range. Everywhere it reverses the normal order of strata. Those strata above it are not greatly disturbed bat those inmedlataly below have been Intensely fold-ed and faulted by the thrust stresses from the southwest. The dip of the thrust westward ia gentle. The age of the thrust can not be fixed precisely. That it took place before the depoaltion of the conglomerate of riocene age of the Cypress Hilla aeeiaa established. It was probably one of the latest effects of the compressive stresses of the Laramide Revolution, the age of ahich ia placed not earlier than the uppermost Cretaceous and not later than the latest Eocene. ' ' ' ' ? -104-"5. "6. General Historr/ of the Structm-e Willis advances a rath^  r Involved history of the structure of 3 Front Ranges. This has been well suonarizod by Daly as follows: The 'Algonkian' strata iverc reduced to a peneplain i:j. early Cretaceous time. This old erosion surface subsided beneath the Benton sea, which extended as far west as about the long-itude of Waterton Lake. During Dakota and Benton tiue there was a very gentle and broad upwarp of lite Front lanpes area, accorcpanied by sed-imentation. in a sea which covered only the eastern part of the belt now occupied by the lewis lango. At the close of the Laranie (presumably at the of the general Larai?idc revolution^ - there was a single uprorp of the 'Algonkian' and overlying Cretaceous beds, f orrd-p- an unsymnetric fold with steeper di^ on the east. there was During the early Tertiary a long period of crustr! rerose during which the upturned rocks were all .ore or less per-fectly planed and the Blackfoot erosion cycle ccifieted. The peneplain was most perfect on uae soft trebaceous reeks, .but there was probably ' lor hilly, post-rn-.turc relief on the Algonkia?i ( Lewis feries) rocks«' In the mid-Tertiary the gieat Lewis overthrrst to^k .lace, hereby the greatly eroded. '.-.Lponkia^ ' bl.ck of L'.e riro t Ranges and the equally broad nass of Lho Geltou-LcCLWala group were uplifted. Apart from local normal faulting, the subsequent istory of the regie** has consisted in steady erosion, leadi:^ to , mature mountain topography." The earliest strata Consisted of pre-C; nbriart, ""Hloozoie ar.d r es-ozoic rocks. In the vicinity of the 49th parallel the flat-lyi*rg beds were gently folded, first in the west and near the noint of forcc. Grad-ually the folds steepened and thickened. Continued pressure foldeJ the Mesozoic beds to the east. All the beds ir* the west were ruijed to a con-siderable height and the . esozolc were probably ouch broken. Since tltat 1, Willis, B. S. Daly, R.A. Ceol. Soc. ^  Vol. 15, 1903, Ceol.Surv.Can. ;'em. 08, n.507. DP. 341 -549 Platg. Vili, 03 f-1 ^ cj ^ c3 Hi .3 <u a cs! m o ¡L) o 3 * ^ M +3 O co -<-) a 3 W r-t (g O > c3 03 o3 3 r¡ ¡L) M a m -r-t 3 ^  o ^ 33 'r! ^ S a m o G 3 o 03 ^ -á +J o >i 0) 03 H ¿3 0<fL,3 8 P H tw O G o -w cá K-cg r-f 0) ^ 03 03 Cg o M G r-t ai <n rW g ' S o a 03 M M 03 a á ^ n a cJ c3 a oí u o cá o) oo-t^a) o^^r-t M cg o, o e?-c¡Dc3 hH g S-) co 03 > ^  03 O 33 O O ^ Q) O t¡-t r-) a C0 -t-< (!) tw 3 O bO+3 a -H a !3n3-<-!OCO tu o M a a ^  3 03 - O -r-t ) ^ r-1 OD-H 03 ^  a ^ 03 3) g O 33 03 03 03 3 O, 33 t¡¡) 33 O Cg +3 M CO ¡> T3 O, 03 r-t >s a T3 03r-)tá 03 eg cg 03 4-* 3 a O ai o 3 C3 o a a 03 r-) O 03 03 S !> 03 ¡o a 03C00303003 H ^  03 03 a 03 g Cj 03 E tiO tg O 93 03 T3 03 35 03 ^ ^ <-) 9) CQTfOf^  03 S 03 a <-< o o C) 3 d ^a03a<^T333Kt C^ O^ -*-) 03b--W -H 3 Q3 3 -W r-^  03+*+^ +^  co aa3(g o a ^  C-) 3 -<-) 03 03 33 a h r-< }=. a a 0+*9.Q30K03 M Î3 M 03 Fl Ü O o M r-t cá >) o 03 -H N a^ M o á 03 a o 03 03s* o o <4 M u O P^  ü -105-tia^ they hava bawn eroded. Continued pressures caused the lees compet-ent beds of the east to fault and thrust* developed, but resistance in-creased and the Lewis Overthraat took up the strain. At the end of the period of compression the western areas were high but not greatly deformed being disposed in moderate folds. Following the relaxation of the pressure, a series of normal faults took place in the west, the deep Flathead valley being one result. There a lake formed and the Twtiary Kishanena beds ware laid down. In the North Kootenay Pasc section the structure differs in the facta that Meaozoic rocks are found in the western division, that the central structural area ta narrow and that reverse faults are very num-erous in the east. The chief feature of the structural development was the a pearance of soles from some of the reverse faults. Movement along these caused rotation on the reverse faults thus giving them the steep dip before mentioned. Normal faulting occurred in the west consequent to re-laxation. 1 ' Structure in the C. P. R. Section !he Rocky Mountains in the area crossed by the 51st parallel are divided by radical differences in structure into three distinct geological 3** eastern section haa bean broken by a number of nearly parallel longitudinal fraaturea into a series of oblong orographic blocks and these are titled and shoved over one another into the form of a westerly 3* McConnall, R*B. Ceol* Surv. Can. An. Rer. 1866. -106-dipping monocline. In the section examined by McConnell were seven prin-cipal faults, besides some of minor importance, and six well-defined blocks, the latter resting on one another in regular succession from west to east. The thrust producing these crust movements and dislocations came from the west and must have been highly energetic in its action, as some of the breaks are of huge proportions and are accompanied by displacements of many thousands of feet. The faulted region is now about 25 miles wide and was probably SO before faulting took place. Overturned folds are pre-sent but are small and of minor importance. The great earth rents seem to have bean produced without much preliminary bending. The titted blocks form a series of more car lees parallel ridges running lengthwise with the chain, bat the intervening depressions are true valleys of erosion and although their direction is determined by the course of the fault, are due to unequal hardness of the formations. Thrust Fnalts One of the largest and moat important of the thrust faults occurs along the eastern base of the chain and brings the Cambrian over the Cre-taceous of the foothills. This fault has a vertical displacement of more than 15,000 feet and an estimated horizontal displacement of the Cmbrian beds of about seven miles in an easterly direction. Central Section The characteristic structural feature of the central mountain area in the C. H* section is open folding. In places great faults displace the strata. It McConaell, R*a. Ceol. Surv. Can. /in. <3^ . S true tur e tetMona acroas the Beaverfoot and Briaco rane a a (After Shepard. Jounnal of Geology, V0I. 34/1926). UBC Scanned by UBC Library Plate IX."- - ' ' *' " The formations of the Ottertail Van Home, Bow and Caatle Moun-tain ranges are flat-lying, gently undulating or dipping to the south-west." 1 western Area The western area of the Rocky Mountains has been intensely de-formed. This is strikingly shown in the Beavcrfoot and Brisco ranges where the folds are dominantly, although no L entirely isoclinal. " Intense folding occurs (in the Field map area) only in areas underlain by softer rocks, such as in the valley of the Otter-tail and in that of the Beaverfoot and in the range of the same name. Anticlinal, synclinal, open, closed, symmetrical, and assynmetrical folds were noted. The latter as a rule are overturned towards the south-west." 2 " Faulting is also an important and prominent structural feature in the Field map area. The faults are normal in character, and in this respect the westward slo s of *5he Rocky Mountain system in this latitude differs from the eastern slope, in which reversed and overthrust faults prevail. " There are two principal systems of faults represented. The one which includes oost of the large breaks has a northwest and south-east trend, which corresponds to the major axis of the mountain folds. The other sys-tem has a north and south trend and t!n- faults are apparently younger than the others. There ar.j numerous minor breaks and slips which are not of significant importance." 5 Summary of the Structure o." the C.^.R. Section The C.P.R. section of the Rocky Mountains is characterized in its eastern part by a series of great fractures and thrust faults, in the centre by broad, sweeping folds, and in the weat by normal faulting, by folding and crumpling, accompanied by the development of cleavage planes, and a limited amount of metanorphism. Among its other more important 1. Allan, J.A., Geol.Surv.Can., -um. Rep. 1913, p.125 2. Allan, J.A., Ceol.-urv.Can., "em.53, p.199 3. Allan, J.A. idem P-202 -108-features, may alao bo notes the absence of unconformities, the relatively smaller amounts of disturbance in the central part of the range than to-wards the edges, the want of similarity in the sequence of the formations east and west of the axis and the prevalence and great thickness of the sediments. Area in the Yellowhead Pass Little information is available in respect of the Rocky Mountain in the Yellowhead Pass section. It is probable that it is similar to that 1 found in the Banff-Golden area. KcEvoy in his necessarily hasty exam-ination of the area between Edmonton to Tete Jaune Cache gives no detail-ed description of structure. In lacea he noted overthrust faults and sharp folding. He seems to doubt the fact of an overthrust on the east-2 ern front. He writes: " On the Brazeau, the transition from the mountains to the level plains is abrupt. Ho folding or crushing is to be seen but a straight uplift without contortion of the beds and apparently without overthrust, for although the talus from the limestones hides the line of contact with the Cretaceous rocks of the level country beyond, these rocks are both found in place in the bed of the stream in pos-itions which seem to preclude the possibility of a lateral movement of any extent." This evideree does not seem enough to preclude the possibility of a feature of structure which is so prominent in the front ranges to the south of this area. 3 Dowli!^ saye of the structure hero: " The general structure of the Rocky Mountains from the International Boundry north to the Saskatchewan River is that of a series of westerly dipping fault blocks of similar strata resting against each other. A repet-ition of form and of strata, and a continuity in the 1. McEvoy, J.D. Geol.Surv.Can.An. Hep. Vol. XI. 1898. p.40 D. 2. idem 3. Dowling, D.B. Geol.Surv.Can. Sum.Pep. 1911 p.208 -109-ranges, therefora, obtains, but in going northward, mora diversity in the form of the blocks is noticeable. The uniform westerly dip and regular repetition of beds is to a great extent replaced by folding of tin- strata, while a greater variety in the outline of the ridges is apparent. " The Roche Miette district forms a part of the outer ranges of the Rocky Mount-ins and is crossed in an east-west direction by the deeply eroded valley of the Athabasca River, into which drain several streams flowing between the tilted and folded blocks of strata that forte the ranges. " The drainage channels that are eut through the mount ins or foothills in many instances anem to owe their origin to breaks in the upthruste; blocks." Peace River Area 1 In a hurried reconnaissance of the Peace River, McDonnell noted: " The rocks exposed along the pass consist principally of gpeyish Paleozoic limestones striking in a north-west direction and dipping persistently to the south-west. Repetition of parts of the limestone series caused by overthrust faults, occur at several points. " Immediately east of the main range, exposures of yellow-ish-weathering calcareous sandstone, probably of Cre-taceous ago, occur in the banks of the river. These are replaced going westward, by greyish limestone.- dipping steeply to the west. The junction between the limestone and the aandstone is concealed in the valley, but there ia little doubt, from the relative position of the two formations, that the contact is a faulted one and that the Paleozoic llmeatone of the mountains here, as else-where along the eastern houndry of the ran e, are thrust up over the Mesozoic rocks of the foothills. * The Peace River section through the Rocky Mountains, thus resembles the Bow River section through the same range, in the predominance of limestones and in the persistent westerly dips due to repetition of the beds by overthMist faulting, but differs from it in its abaenoe of beds newer than the Triessic and in the gradually increasing age of the rocks from east to west." 1. McConnell, R.O. Geol.Surv. Can. An. Rep Vol.Vll, 1894. p.32C. Hard River footing McConnell ^  " The Una of crunpling and upheaval to which this range is due die away at the Liard." Approaching the mountains from the west the beds are horizontal but are soon thrown into alraost vertical attitudes and have the appear-ance of a aharp anticlinal. Mesozoic strata are found on both sides of range. 2 Structure of the Rocky mountain Trench Schofield writes; ^  " The Rocky Mountain Trench is the r.iost reinarkable structural feature of the Canadian Cordillera. It extends from the 49th parallel of latitude at least to the boundary between British Columbia and Yukon." The Trench is the result of normal faulting which took place in the later stages of the mountain-building and of erosion. " Thus the Rocky Mountain Trench may be divided into two portions, a northern one which includes the ''eace Ri\er drainage, due to normal river erosion, and a southern portion which is due to faulting primarily." 4 Section of Trench at 49th Parallel The Trench at the 49th parallel is the result of a normal fault of large throw en the east side and a small reverse fault on the western aide. The block consists of a long, narrow mass, which has been tilted en a longitudinal axis which was nearer the western border of the block se that its inclination is to the east. 1. "eConneil, R.cl Geol. 'urv.Can. ^ ^ " /**< a. SH&eiMclA, S.J. Royal sec.Can., roc.& Trans. 1920. t.lv. 3, Ida* P* 36 1* Daiy. R.A. Keol.Surv.Can. en.6^  , 1915. 3.113 -111-Seotion at Ball River The structure at Bull River is a continuation of that farther *{ aouth at the boundary line. ', Section at Canal Flats The structure is a normal failt with the apparent downthrow on the western side bringing the Beltian-Kitchener formation into contact with the Mid-Cambrian Elko formation. The throw is purely a matter of conjecture and may be in the neighbourhood of 10,000 feet. Section at Golden Describing the structure of the Trench at Golden Daly says:^ * The master fault of the Trench is normal with downthrow on the north-east." Section from Surprise Rapids to Lake Timbaskis Faulting in the Trench has brought 'aleozoic rocks on the east aide to e level with Archean rocks on the west. Section from Tete Jaune Cache to Big Bend of the Fraser At Tete Jaune Cache, shearing and crushing of the rocks exposed in the floor of the Trench haa occured. This breakage is considered to be related in age to similar shearing and faulting whieh have determined the Treneh to the south. The Bow River Series borders on the north-east alepo of the trough from Tete Jaune. Cache to Goat River. Northward twaa thie river the reeks on both eides are of similar age. " " " . Oool. Sarv. Can. ^em.60, 1915. p. 115. -112-Daly writes: ^  " Thua, for at least 850 miles of its length the Rocky Mountain Trench is located on a continuous zone of faulting which is characterized by very great upthrow on the west." Other views of the structure of the Trench have been taken by, Shepherd in artioles in the Journal of Geology 1922 and 192. pace does mot permit a detailed exposition of his theories, ''uoting him in 2 part: " Structurally the Trench has hitherto been considered aa a sort of graben or at least the product of norisal faulting " " The Rocky Mountain Trench does not appear to be tho unit in development and structure that it has been thought to be. It appears instead to have been pro-duced partly by normal erosion, partly along lines of structural weakness, and partly by the escariment of a fault. Even is this last instance, the faulting is probably of the thrust rather than of the normal type." 3 Shepherd's second paper^ discusses the geology of the Trench and the ranges east of it between the towns of 'inddmere and Golden. The structure is oomplex with nnch isoclinal folding and thrust faulting. A cooperative study ia afforded by croas-sections of the Beaverfoot-Briseo Ranges. A aeries of transverse faults have helped produce some intravalley ridgea, but were not important in developing the Trench. A huge breccia, several hundred feet thick and miles in extent, is found at many placea along a vertical bedding-plane fault which probably has several milea of displacement. Part of the Trench has a horst type of structure, rather than the graben type of structure. 1. Daly. STC Geol.Surv.Cen. Hem 66 1915, p. 113 B* Shepherd, P.P. Jour. Geology, vol.3 , 1922. p.131 3. Idem -.159 4. Idem vol.34, 1926 p.C23 -113-" That much of a tramendoualy long depreaaion like the Rocky Mountain Trench should be 1 cated along a horat would seam remarkable, but in this connection it is interesting to note that in a reconnaissance of the Qmineca-Findlay Rivers, 400 miles farther north along the aame Trench, MeConnell found the same general relations of older rock within the Trench and younger on each side. " 1 UBC Scanned by UBC Library 1. Shaw&M*, y. Pi Jour. Geol. Vol. 34. 1926, p. 641. CHAPTER V. HISTORICAL 680L0S? The Rocky Mountain area has had a remarkable history. During the millions of years of Beltian, Paleozoic and Mesozoic history it was main-ly an area of deposition. In a comparatively shore period of time this sea bottom was elevated into a great mountain system. Revolutionary changes took place to occaaion such a transition. These changes will be discassed In the pages following. ^positional History. The history of the Rocky Mountains is closely linked up with that of other parts of the Cordillera. That relationship has been discussed 1 by Schofield in a paper on the record of the Canadian Cordillera. In this paper he suggests, for the first time, the occurrence of a land mass, Caacadia, in an area now occupied by the waters of the Pacific Ocean. During Beltian times a narrow basin of sedimentation stretched northwestward through the eastern part of British Columbia to Yukon and Alaska. A Palaoao&c and early Mesozolc basin of sedimentation extended from Caacadia eastward to the Canadian Shield. During the Jurassic re-velation tha Selkirk Mountains appeared and in Cretaceous times a basin of sadimant^&on lay to the east of the Jurasside Selkirke. -WiL.- .J. .1- . u, . — - — - — — — - — 1. Sehsflald, s*j. Royal Soc.Can. Proc.a Trans. 19;,. Pt.17. p.?f -115-Beltian epositional History "Daring Beltian times a narrow basin of sedimentation stretched wrthwestward through the eastern part of British Columbia" 1. This included gii the area now occupied by the Canadian Rockies. "That a land mass was not far distant to the west is indicated by conglomerates in the western range of the mountains near Boll River. No conglomerates are found ^t the vicinity of the 49th parallel, but in the neighbourhood of Meld, alcott und -llan describe minor thicknesses of fine conglomerates or coarse sandstones. Daly states that limestones of Beltian age become relatively more abundant to the east." 3. Thus the Beltian w.-s a ti e of practically continuous sedinea-tation. This sedimentation is generally regarded as having taken place in shallow waters as is evidenced by the prevalence of ripple i^ arks, mud cracks, and casta of salt crystals in the rocks. "Divers opinions are held as to the origin of the Holt eries by those who have worked in them, '..lie Kintla, "rirmell a,id prob-ably the Appekunny are certainly of continental origin as shown by their unmistakable characteristics. The dolonitet are stat-ed by Daly to be the chemical precipitates in marine basins while ^ alcott. su gests that t ey are of epicontinental origin and precipitated in fresh water through the arency of algae. 'Whatever its origin this pre-Caibrian series forms a unib, though opinions differ as to how distinct it is from the succeeding Paleozoic series.." 3. Paleozoic Deposition 4 MacKenzie taa thus sumnarized opinions in respect to the contact of Beltian and Paleozoic rocks : "alcott considered them to be separated b/ a lengthy period of uplift and erosion, while Daly states the view th-t these two series form a simple Paleozoic-beltian goosynclinal prisn, which is only locally interrupted by unconformities, ^ vicence that there was as interval of erosion is given by chofield. At Elko he found the lowest Xidlle Cambrian, Burton formation, 1. chofield, S*J. Royal Soc.Can. 'roc. A Trans.1923 Pt.IV. p.92. St Schafield, S.J. Idem p.93. 3,MaeK*szie, J.D. Royal Soc.Can. Proc. & Jrans.1922 Pt.IV. p.99. 4.HacKenzie, I.D. Royal Soc.Can. *roc. & Trans. p.99. -116-lying without angular diacordanee on roeks which he aasigna to the pre-Canbrian. Further evidence of a break in sedim-entation ia given by Adams and Diek, and Rose also recognizes a diaconformity at the base of the Paleozoic. In the stunner ef 19Z1, Sehofield discovered a conglomerate at the base of the Cambrian containing Olenellus and resting on Beltian Though aedmntetion may have been interrupted at the end of the Beltian, the break was followed by a long period of desposition. In respect of "In this basin ( of which the Rocky Mountain area was a part ) sedimentation was almost continuous throughout the Paleozoic and early Meeozoic periods. Local dieconformitiee are pre-sent throughout the basin, but in general it may be said that no land ansa sufficiently high to furnish any great amount of sediments roee above this continental sea. Ko folding or or-ogenic movements interrupted the process of sedimentation in the basin as no structural unconformity has been recorded from the sediments which collected in this Paleozoic and early Meaozoic geosyncline." The sedimentation was marine resulting in the accumulation of immense thicknesses of fossiliferous limestones, shales and sandstones. In the area about the Crowanest Pass and southward, rocks representative of the time from lower Pennsylvanian to the lower Jurassic are absent. "It ia supposed that from the beginning of the Permian to lower Jaraaaic this region was land-, a terrene of low relief, main-ly ef limestones but with seme sandstones - undergoing sub-aerial weathering with prob bly but litHe loss of the products ef reek disintregration". North of the Crewaneet area, however, sedimentation went on P until the latter part of the Paleozoic when according to .'acKenzie "Near the close of the Paleozoic er the Rocky Mountain aynelinal waa broadly uplifted without appreciable deformation." recite** 3. JB^g^haia, S.I. Royal Soc.Can. Proc.& Trans I.D. Royal Soc.Can Proc.& Trans J.D. Idem Heeozoic Deposition it ia prob^le that a general sinking took place in the Rockiea ia A e earAy part of the Mesozoic. Trlassic formations Juraaaic aedlaMits are widespread. An interpretation of the history of the Jurassic peaMod ia the ¡southern part of the Rockies is given by Tram the varying thickness and uniform character of the sediments formed in the Pernio it ia apparent that great volumes of fine mad were delivered to thin sea by rivers flowing from low land to the west, and there may have been several large estuaries a&sng the weateam edge of the marine basin at that time -A thin bad of a greenish rock which cLeam haa termed tuff oeeara in the Pernio Alatrict. If its designation as tuff be esawct, it marks the firat evidence of igneoua action in the Rocky Mountain area aince the pre-Cambrian Purcell lavas." Do^lte the seeming gradation of the Femie formation into the Kootenay, these formations are considered to have been separated by a 3 considerable time interval. During this time the marine waters must have gradually withdrawn and wideapread freah water basins succeeded thasu In these ahallow lakes the Kootenay measures were laid down. "The western expoau^e of Kootenay strata are notably coarser than thee* oocarriag farther east - The rejuvenated streams (from a weatem land maaa) spread over the newly exposed soft lake aaABaeate, end removed a portion of them, covering the remain-der with a veneer of cherty and quartzitlc pebbles - The graTWl was apraad evenly over an enormous extent of territory and ia now found overlying the Kootenay formation throughout t - the aouthem Rocky Mountaina." 4 A saaaatt^ Mt Apant Young haa already been given under the general deacriytion of the reeks of that period and need not be repeated here. *May extMd throughout the length of the Rocky Fountains", 1 ' } a Min. of Can. Royal See. Can. Proc. & Trans. ?*A* aaaA. & Boon. Min. of Can. y*D* Royal Soe. Can. Proc. &. Trans. p. 154 p. 100 p . 155 p. 102 y -118-In tbia, lika MacKenzie, ho pointe ont that oro^anic oovw-ìenta, in late Jweeeie ttsa in an area west of the praaent Rocky i%^ntaina, gava rise te coagloMoratas of the Crataceous and was the reason for the is-ereaeÌBg thieknass of Cretaeaous a^dioe^ts in a aestaard direct ion. whole deposi tional history of the Roeky Sountaina.î^y well 1 ho aamaanaed la thc vords that usas of the hlatory of the area et the 39th parallel: * It vuld he wobable that durlng the aozole, t is part of the Cordi liera was nev r far --¡Love eoa levai, "rea the earliast pya-CMdbrl^m in tî^ e t^ oe^ y Xoamtaiaa to tì^ e U^^er ^retacoous 01- early ïertiury, a streteh of ti-tse raprasont-iag moat of the ì ecorde : geologie history of the globe, there la no oviô^mca in this ra?-ioa for ore tb.an rolat-ively allait apllfte and éepraasio;-^  vlth no more .^for-mation than that eoneenuent of differenti al subsida3Mte." Structural ^istory. 3o«a aoiyaaat on the history of the atructur 1 devalops^nt of the *!aeky Moaatalns hai already been c^de \mdar the discussion of structure and hanae ^at history need be lealt with in a brand imy. !hortly after the cloae of the Crotaeeous the great :-oeky Mount-ain awe bullt. The ereetioìn of this Kxì -ntaln systea occupied a peri od of vezy aâîayt duration in com^rlaon to the time reruired for tha- uccus-ì-ulatian af the materiale out of t^ich they are bullt. lite period of E their risa is atatad by :chofield to be : " Boat-Upper Cretaceous and. preU;per roe^ ne." 53J Geol. arv.of CarJ' âm.^ Ì91S ' p.C07 oyal aoc* of Caa. MSS . Hfaa. r. TraM.Pt.l?. pici. t .^ ¡w^ y -119-The Wogenic history of the Rocky Mountains es stated by Mae Kami* ^ aad others in brief is that compression from the west first gently folded the western area of the system. Further pressure folded it mere, but, by thickening the folds caused them to become stronger,with the result that the pressure was taken up in the eastern ranges by thrust faulting on a large scale. Continual pressure caused the great Lewis Over-thrust along with a revolution of the imbricate fault blocks giving them ateeper dips. yellowing compression came relaxation with normal fault-ing. Somewhat divergent views are held by other workers. -illis sug-geeted the more complicated history already mentioned. 2 Dealing has also proposed a different view of the orogenic history of the Rocky Mountains from the commonly accepted view. His inter-pretation will be briefly summarized. The sinking of the Rocky Mountain geosynelinal would have the tendency to cause tension at its western mar-gin. A final reault would be normal faulting. s?ith the break and conseq-uent relaxation of tension, an upwarping of the fault scarp would occur and great displacement would be the result. The present division of the system into a weetam area of older rocks and an eastern area of younger formetions indicates a great normal fault at the edge of the Cretaceous baain. A fault ia now known which once had a displacement of 30,00. feet. Thus at the beginning of Cretaceous times a long block appeared in the weatesm area Of the Rcekiea. This bleak is now present and extends from Pernio northward. It ia widest at Castle Mountain and is known at Jasper Pose whOKO Mt*Rob*on has been carved from it. The western Rocky Mountains Royal 3oe. of Can. Proc. & Trans.1922 t.lV. Royal Soc. Of Can. rroc. & Trans. 1922 P .IV. p.175. -120-are fia^ aed frtM Ala block and have taken their present form eubeequent intense sculpturing and a gentle folding eanaed by egression in the late aeeene. Accompanying this Eocene folding came the intrusion of the lee River complex* A period of tension at the end of the Eocene is not evident and the drainage of the western mountains has an age earlier than that time. Ia the late Eocene occurred the elevation of the plains and the formation of a great antiellnmrium in the western part of the Rocky system. Feu It blocks dipping west were further inclined and, being hinged near the Rocky Mountain T&enah, have caused its present graben structure. The age of the major normal fault which divides the Rocky Mountains in age end materials is to be judged especially from the coarse sediments of the Keotenay and the Elk conglomerates. These conglomerates dwindle in thtekneas eastward. The age of the faulting can then be set as " The beginning of the Cretaceous with probably a major period of movement at the close of the Kootenay period." 1 Eastern Division Deposition continued in the Eastern Division of the Rockies during all ef Cretaceous time under varying conditiona. The folding and faulting of the mountains occurred in the late 2 History of Drainage It is probable that prior to, or in early Cretaceous times orogenic took piece in an area somewhat west of the Rocky ibuntain Trench. peneplained before the end of the period. "JiiHMi't roc. Trans.19ZZ. pTTCI Proc. & Trans.1930.It.IV. p.tO-97. Jb nw*jR*3+ B*B* R6y*iSoc. of Can. Sehofiald, s^y* . Royal sec. of can. -121-Rivera flawing eastward through them eroded headward to the interior baain to their weat. Included in these rivers were probably the ancestral rivers of the present Liard, Peace and the rivers now flowing eastward through the Yellowhead, Kicking Horse and Growsnest Passes. The ances-twa of ^ a KooteMty and Columbia were also present in Cretaceous times. With the uplift of the Rockies in the 3ocene many of the streams continued to flaw eastward and to cut their valleys across the rising mountains. Such rivers were those in the valleys of the present peace, Athabaaca, Bow, and Crowaneat Rivers. Some of the streams were unable to maintain their eouree eastward and became tributaries to the larger rivers. Such streams, separated by divides, occupied portions of the de-pression which later became the Rocky Mountain Trench. Normal faulting in the Eocene changed the drainage courses consid-erably* Faulting in the Trench does not extend north of the Big Bend of the Traaer and hence the Hard and the Peace continued their courses un-disturbed, but the rivers which crossed the faulted area had their drain-age diverted into the Trench. Its rivers then flowed southward. The normal faulting also caused a divide to appear in the former through vallaya of the Rocky Mountains with the result that short streams now flowed westward into the Trench. Gradually these streams pushed their watersheda eaatward. Thus were formed such rivers as the Kicking Horse and the Elk. By continual pushing of the headwaters eastward, they were enabled to form the western portions of the numerous passes through the -122-Glacial Hietory. The glacial history of the Rocky Mountains is not yet fully 1 worked out, Dawson has stated that there were at least two glacial 2 periods. Speaking of the Purcell range, Schofield says : "The records of the first Glacial period, if ever present in the Purcell range, have been removed during the erosion periods which followed this advance of the ice....... The climate after the firet retreat of the Ice, as indicated by the plant fossils found in the St,Mary silts, was, accord-ing to Mr.Arthur Hollick, milder than that of middle United States. This period of comparative warmth was followed by another refrigeration of the whole Cordillera." Movement of the ice in the Rocky Mountains was in the main southward and continued only a short distance east of the foothills. A considerable modification of topography was effected in the forma-tion of U-ahaped valleys, lakes, lateral and terminal morraines. Glacial action still continues in the higher altitudes though present glaciers are in retreat. I* Daaaon, 3*M. Royal Soc. of Can. ''roc. Trans. 1091, Vol8. Pt. IV. pp.3 - 74. & Schefield.S.y. Geol.Surv. Can., Bern. 76, 1915, p. 103. BIBLIOGRAPHY Adams, ?*D* & Dick, .¿.J. "Discovery of Phosphate of Linn In the Rooky Mountains." Canada, CcmmiBaion of Conservation. 1915. Allaa, J*A* Blackwalder, Burling, L.D. "Geology of the yield Map ¿rea, B.C. and alberta." Ged^surv.can.summary Report, 1911. "Rocky Mountain Section between Banff, Alberta and Golden, B.C. along the C.P.R." Geol*Surv.Can.summary Report 1912. "Rooky Mountains, Bankhead to Golden" 6eol.8urv.Can. Guide Book aio.8.1913. "Geology of the Field Map Area, B.C."-Geol.Surv.Can. Memoir 56. 1914. "The Geology of the Rooky Mountains" Canadian Alpine Journal 1917. "Handbuoh der Regionalen Geologle, United states of ja^rlca." "A Cambro-Ordivician Section in the Boaverfoot Range, near Golden.B.C." The Geological Magazine, Vol.59.1922. "A Cambro-Ordivician Section near Mount Robeon, B.C." Bull. Geol.soc* unerica. Vol.34. 1923. "Geology of the Canadian Rooky Mountains." Canadian JLpine Journal.Vol.2. 1920. "Oragenic and Physiographic Histojey of the Rooky Mountain Geocynclinal." Canadian alpine Journal.Vol.2. 1920. "Coast Range, Lytton to Vancouver." Geol.3urv.Can. Guide Book No.8.1913. ." - Y* * .s Clapp, O.H. Chamberlin, R.T. -2-"A Geological Reconnaissance on Graham iBland, Queen Charlotte Group, B.C." Geol.surv.Can. Summary Report 1912. "Vancouver Island." Geol.surv.Can. Guide Book 1:0.8. 1913. "The APfdachian Folds of central Pennsylvania. " Journal of Geology. Vol.18. Ho.J. 1910. "The Significance of the Framework of Continents." Journal of Geology, Vol.32. ho. 7. 1924. "The Jedge Theory of Diastro^hism." Journal of Geology, Vol.33. Ko.8. 1925. Collie, J.N. "Exploration in the Canadian Rocky Mountains." The Geographical Journal, Vol.17. 1901. Daly. R.A. "Furtner Exploration in the Canadian Rocky Mountains." The Geographical Journal, Vol.21. 1903. "Geology of the north jnerican Cordillera at the 49th parallel." Geol.surv.Can. Memoir 38. 1912. "Introduction to the Geology of the Cordillera." Geol.surv.Can. Guide Book I;o.8. 1913. Dawto*. M * 4 ' "A Geological Reconnaissance between Kamloope and Golden, B.C.,alon^ the C.P.R." Geol.surv.Can. Jeoolr 68. 1915. "Preliminary Report on tne ihysical and Geological Features of that portion of the Rocky Mountains between Latitudes 49° and 51°31'." Geol.Surv.Can.Annual Report Vol.1. 1885. Ds*aoH, C.H. (Continued) Diller. 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"The topography ^f California." journal of Geology, Vol.5. 1897. Brief Review of l-.ocky mountain Structure." Journal of Go-.logy.Vol.32. 1924. -4-Gilbert, G.E. "Studies of Basin Range Structure." U.S.G.S. Prof.Paper.No.153.192B. Jones, L.R. and Bryan, P.W. "North America, An Historical, Economic and Regional Geography." 1924. Kindle, K.M. Leach, K.W. McConnell, R.G. McEvoy, J. "A Standard paleozoic Section of the Rooky Mountains near Banff, Alberta." Pan-American Geologist, Vol.42. 1924. "Geology of the Blairmore Hap Area,Altcrta." Geol.Surv.Can. Su;wnary Report, 1911. "Report on the Geolor*ioa^Fentures of a Portion of the Rocky mountains accompanied by a section measured near the 51st Parallel." Geol.Surv.Can. Ann.Rept. 1886, Pait "D". "Report on an Exploration in the Yukon and Mackenzie Basins, Ii.'. .T." Geol.Surv.Can. Ann.Rept.1888-89, Pa^ rt "D" "Report on an Exploration of the Fihlay and Omineca Rivers." Geol.Surv.Can. Ann.Rept.1894. Part "C". "Prince Rupert and Skeena River." 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"Relationship of the Pre-Cambrian (Beltian) ^errane to tbe Lo\?er Camtri^ Strata of S mth-eastem B.C." Geol.Surv.Can.^ull.i^o.35. Geol. Series Ho.42. 1922. "The Geolorical Record of the Cordillera in Canada." Royal Soc.Can. Proc.and Trans. Vol.17. 3rd Series, Sec.4.1923. "The Structural Relations of the Purcell Range and the Rocky Mountains of Canada." Jour.of Geol.Vol.30.No.E.1922. "Problems in Stratigraphy along the Rocky fountain Trench." Journ^f Geol.Vol.30.No.5.1922. -7 Shepard, P.P.(Continued) Shimer. H.t<. "Further Investigations in the Rooky Mountain Trench." Jour.of Geol. Vol.34. 133 6. "Upper Paleozoic Faunas of the Lake Minnewanka Section, near Banff, Albert^." Ge ol. Surv. Can .Tm*l. No. 42. Series 45, 1926. Smith, G.O. and Calkins,F.C."A Geological Reconnaissance across the Cascade Range." Spencer, A.C. Stewart, J.S. TJalcott, C.D. Walker, J.F. U.S.G.S. Bull.235. 1904. "The Pacific Mountain System in B.C. and Alaska." Bull.Geol.Soc.America.Vol.14. 1903. "Geology of the Disturbed Belt of South-western Alberta." Geo1.Surv.Can.Memo ir 112,1919. "Pre-Cambrlan Rocks of the Bow River Vailey, Alberta." Smithsonian Miscellaneous Collections,Vol.53.Ho.7. 1910. "Nomenclature of Some Cambrian Cordillpran Formations." Smithsonian Misc.Colls.Vol.53, Ho.l, 1910. "Cambrian Formations of the Robson Peak District, B.C. and Alberta." Smithsonian Misc.Colls.Vol.57, No.12, 1C14. "Geology and Mineral Deposits of Windermere Map Area, P.C." Geol.Surv.Can. Memoir 148. 1926. Willis, Bailey, "Stratigraphy and Structure,Lewis and Livingstone Ranges, Montana." Bull.Geol.Soc.America, Vol.13. 1902. "Rocky fountain Structure." Jour.of Geol. Vol.33. No.3. 1925. 


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