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SMITHSONIAN MISCELLANEOUS COLLECTIONS VOLUME 116, NUMBER 5 Cfjarle* £. anb Jfflarp "^Xaux flKHalcott 3Resiearcf) Jf tmb MIDDLE CAMBRIAN STRATIGRAPHY AND FAUNAS OF THE CANADIAN ROCKY MOUNTAINS (With 34 Plates) BY FRANCO RASETTI The Johns Hopkins University Baltimore, Maryland SEP Iff 1951 (Publication 4046) CITY OF WASHINGTON PUBLISHED BY THE SMITHSONIAN INSTITUTION SEPTEMBER 18, 1951 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOLUME 116, NUMBER 5 Cfjarie* B. anb Jfflarp "^Taux OTalcott &egearcf) Jf unb MIDDLE CAMBRIAN STRATIGRAPHY AND FAUNAS OF THE CANADIAN ROCKY MOUNTAINS (With 34 Plates) BY FRANCO RASETTI The Johns Hopkins University Baltimore, Maryland (Publication 4046) CITY OF WASHINGTON PUBLISHED BY THE SMITHSONIAN INSTITUTION SEPTEMBER 18, 1951 BALTIMORE, MD., U. 8. A. CONTENTS PART I. STRATIGRAPHY Page Introduction i The problem I Acknowledgments 2 Summary of previous work 3 Method of work 7 Description of localities and sections 9 Terminology 9 Bow Lake 11 Hector Creek 13 Slate Mountains 14 Mount Niblock 15 Mount Whyte—Plain of Six Glaciers 17 Ross Lake 20 Mount Bosworth 21 Mount Victoria 22 Cathedral Mountain 23 Popes Peak 24 Eiffel Peak 25 Mount Temple 26 Pinnacle Mountain 28 Mount Schaffer 29 Mount Odaray 31 Park Mountain 33 Mount Field : Kicking Horse Aline 35 Mount Field : Burgess Quarry 37 Mount Stephen 39 General description 39 Monarch Creek IS Monarch Mine 46 North Gully and Fossil Gully 47 Cambrian formations : Lower Cambrian S3 St. Piran sandstone 53 Copper boundary of formation ?3 Peyto limestone member 55 Cambrian formations : Middle Cambrian 56 Mount Whyte formation 56 Type section 56 Lithology and thickness 5& Mount Whyte-Cathedral contact 62 Lake Agnes shale lentil 62 Yoho shale lentil "3 iii iv SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Il6 Page Cathedral formation 64 Type section 64 Lithology and thickness 65 Cathedral-Stephen contact 69 Ross Lake shale member 69 Stephen formation 70 Type section 70 Lithology and thickness 72 Stephen-Eldon contact 74 Ogygopsis shale lentil 75 Burgess shale lentil yy Faunas 79 General statement 79 Fauna of the Bonnia-Olcncllus zone 81 Lower-Middle Cambrian boundary 84 Fauna of the Wcnkchcmnia-Stcplioiaspis zone 87 Fauna of the Plaghira-Kochaspis zone 90 Fauna of the Albert ella zone 93 Fauna of the Glossoplcura zone 96 Fauna of the Bathyuriscus-Elrathina zone 99 Order of succession of the faunules 108 Species not discussed in this paper no Geographic and vertical distribution of trilobites 112 Environment of deposition 117 Index of localities 121 PART II. PALEONTOLOGY General statement 131 Terminology 131 Classification of Cambrian trilobites 132 Descriptions of genera and species of trilobites 133 Order Agnostida 133 Order Eodiscida 137 Order Opisthoparida 138 Superfamily Burlingioidae 138 Superfamily Corynexochoidae 139 Family Zacanthoididae 140 Family Dolichometopidae 156 Family Corynexochidae 188 Family Dorypygidae 188 Family Ogygopsididae 190 Family Oryctocephalidae 192 Superfamily Ptychoparioidae 198 References 251 Explanation of plates 255 Index 271 LIST OF PLATES (All plates following page 270.) 1. South face of Mount Temple. 2. Middle Cambrian strata on Mount Stephen and Park Mountain. 3. Northwest face of Mount Stephen. 4. Lower part of the northwest face of Mount Stephen. 5. Interfingering limestone and dolomite in the Cathedral formation. 6. Anomalous lithology of the Cathedral formation on Mount Stephen. 7. East face of Mount Odaray. 8. Trilobites of the Bonnia-Olcnellus and Wenkchemnia-Stephenaspis zones. 9. Trilobites of the Wenkchemnia-Stephenaspis zone. 10. Trilobites of the Wenkchemnia-Stephenaspis zone. 11. Trilobites of the Wenkchemnia-Stephenaspis zone. 12. Trilobites of the Wenkchemnia-Stephenaspis zone. 13. Trilobites of the Plaginra-Kochaspis zone. 14. Trilobites of the Plaginra-Kochaspis zone. 15. Trilobites of the Plaginra-Kochaspis zone. 16. Trilobites of the Plaginra-Kochaspis zone. 17. Trilobites of the Albertclla zone. 18. Trilobites of the Albertella zone. 19. Trilobites of the Albertella zone. 20. Trilobites of the Albertella zone. 21. Trilobites of the Albertella (?) zone. 22. Trilobites of the Albertella ( ?) zone. 23. Trilobites of the Glossopleura zone. 24. Trilobites of the Glossopleura zone. 25. Trilobites of the Bathyuriscus-Elrathina zone (Burgess and Ogygopsis shales). 26. Trilobites of the Bathyuriscus-Elrathina zone (Burgess and Ogygopsis shales). 27. Trilobites of the Bathyuriscus-Elrathina zone (Burgess and Ogygopsis shales). 28. Trilobites of the Bathyuriscus-Elrathina zone (Burgess and Ogygopsis shales). 29. Trilobites of the Bathyuriscus-Elrathina zone (Burgess and Ogygopsis shales). 30. Trilobites of the Bathyuriscus-Elrathina zone (Burgess and Ogygopsis shales). 31. Trilobites of the Bathyuriscus-Elrathina zone. 32. Trilobites of the Bathyuriscus-Elrathina zone. 33. Trilobites of the Bathyuriscus-Elrathina zone. 34. Trilobites of the Bathyuriscus-Elrathina zone. TEXT FIGURES 1. Map of the area indicating location of sections 10 2. Mount Whyte section 17 3. Contour map of Mount Stephen indicating fossil localities 4° 4. Section in the eastern and western parts of Mount Stephen 44 5. Map indicating thickness of the Mount Whyte formation 61 v Cfjarlefi 29. anb jffllarp ^Taux flialcott 3&eaearcl) Jfunfc MIDDLE CAMBRIAN STRATIGRAPHY AND FAUNAS OF THE CANADIAN ROCKY MOUNTAINS By FRANCO RASETTI The Johns Hopkins University Baltimore, Maryland (With 34 Plates) PART I. STRATIGRAPHY INTRODUCTION THE PROBLEM The area described in this work is situated on or near the Conti- nental Divide in the southern Canadian Rocky Mountains. The portion of the Divide investigated centers around Kicking Horse Pass and extends northwest to Bow Pass and south to Wenkchemna Pass. The mountains forming the Divide are known as the Waputik and Bow Ranges, respectively north and south of Kicking Horse Pass. All the localities discussed are either in Banff National Park, Alberta, or in Yoho National Park, British Columbia. Stratigraphically this study covers the lower portion of the Middle Cambrian, i.e., the Mount Whyte, Cathedral, and Stephen formations. These strata average, in the area investigated, a thick- ness of somewhat over 2,000 feet and represent about one-half of the total thickness of the Middle Cambrian series. Immediately un- derlying and overlying formations are occasionally discussed. The area is famous for the great development, high fossil content, and splendid exposures of the entire Cambrian system. The simple fault-block structure of these mountains facilitates the study of the stratigraphy. Hence the Canadian Rocky Mountains attracted the at- tention of the foremost student of the Cambrian in North America, Charles D. Walcott, who devoted more time and work to the Cam- brian in this area than in any other portion of North America. He established the general Cambrian section of the region, named the SMITHSONIAN MISCELLANEOUS COLLECTIONS, VOL. 116, NO. 5 2 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. Il6 formations, described a number of sections in detail, and made an extensive study of the fossils. His discovery and study of a large fauna of invertebrates preserved in exceptional manner in the Burgess shale represents one of the greatest paleontologic contributions of all time. Walcott fully realized the provisional character of some of his work, a consequence of the enormous geographic and stratigraphic range of his studies, the rugged topography, and difficult communica- tions. He often pointed out the necessity for more detailed investi- gation and especially more intensive fossil collecting by future stu- dents. The choice of the particular problem discussed in this paper was determined by the following considerations : The area was chosen for reasons of accessibility and because it includes the type sections of the formations that it appeared desirable to revise. The portion of the stratigraphic column investigated, the lower half of the Middle Cambrian, was chosen because of the poor knowledge of the faunas of this age, and because the southern Canadian Rockies probably con- tain one of the thickest, most fossiliferous, and better-exposed sec- tions of this stratigraphic interval. Hence a study of the faunal suc- cession in this area was expected to present much more than local interest leading to the establishment of a standard sequence for the entire Cordilleran province. The results rewarded these expectations, as the writer believes that the fossils here described give for the first time a clear idea of the succession of trilobite faunas that followed the Olenellus fauna and preceded the Albertella fauna. The Cambrian beds underlying those investigated (the Lower Cam- brian sandstones) and those immediately overlying (the Eldon dolo- mite) are but sparsely fossiliferous and are represented by more fossiliferous equivalents in other areas of the Cordilleran province; hence they presented less interest than the strata studied in this work. ACKNOWLEDGMENTS The present work was made possible by grant No. 509-47/48 from the Penrose Bequest of the Geological Society of America. The grant defrayed the writer's and an assistant's expenses for two field seasons. The writer is glad to acknowledge his deep gratitude to the Society. Thanks are also due to the Department of Mines and Resources, Ottawa, for permitting the collection of fossils in the Canadian National Parks; and to the officials of Banff and Yoho Parks for their helpful cooperation. NO. 5 MIDDLE CAMBRIAN STRATIGRAPHY—RASETTI 3 The writer is also greatly indebted to