Stratigraphy and Geologic History of the Uppermost Cretaceous, Paleocene, and Lower Eocene Rocks in the Wind River Basin, Wyoming GEOLOGICAL SURVEY PROFESSIONAL PAPER 495-A Prepared in cooperation with the Geological Survey of Wyoming and the Department of Geology of the Un,iversity of Wyoming as part of a program of the Department of the Interior for development of the Missouri River basin PROPERTY OF: C ~~~~~~;'H! ~t: P..~n~~~C' U• ~j'· ~t~YV-.L:L.~u \JiLJ i\.Jlll~•...:-....,.:; AREA VI r\·;h-JERAL REJOURCE Ui-k-a~A;a Stratigraphy and Geologic History of the Uppermost ~- ,/ ·~. .,......... , . i Cretaceous, Paleocene, and • Lower Eocene Rocks in the Wind River Basin, Wyoming By WILLIAM R. KEEFER GEOLOGY OF THE WIND RIVER BASIN, CENTRAL WYOMING ,\if GEOLOGICAL SURVEY PROFESSIONAL PAPER 495-A Prepared in cooperation with the Geological Survey of Wyoming and the Department of Geology of the University of Wyoming ·as part of a program of the Department of the Interior for development of the Missouri River basin ~ .·~ {( . --....~:...' UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1965 .<~ UNITED STATES DEPARTMENT OF THE INTERIOR STEWART L. UDALL, Secretary GEOLOGICAL SURVEY Thomas B. Nolan, Director For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 CO~ TENTS Page Page Abstract __________________________________________ _ A1 Stratigraphic sections-Continued 2. Lance Formation at Conant Creek ___________ _ A64 Introduction--------------------~------------------ 2 Acknowledgments _____________________________ _ 2 3. Lower part of Fort Union Formation, California Co. Madden L __________________________ _ History of investigations ________________________ _ 3 65 Geography __________ -·- ____________________ .____ _ 4 4. Fort Union Formation near Ethete ___________ _ 66 Geologic setting ___________________________________ _ 5. Fort Union Formation at north end of Alkali 6 Butte anticline ___________________________ _ StratigraphY--------------------------------------- 6 66 Upper Cretaceous Series ________________________ _ 8 6. Fort Union Formation near Castle Gardens ___ _ 67 7. Indian Meadows Formation, sec. 3, T. 5 N., R. Rocks underlying Meeteetse Formation and 5 w____________________________________ _ Lewis Shale _____________________________ _ 8 68 Meeteetse Formation and Lewis Shale ________ _ 8 8. Partial section of Lysite Member of Wind River Lance Formation __________________________ _ 17 Formation, sec. 29, T. 39 N., R. 90 W ______ _ 69 Paleocene Series _______________________________ _ 21 9. Partial section of Lost Cabin Member of Wind Fort Union Formation ______________________ _ 21 River Formation, sec. 22, T. 38 N ., R. 89 W __ 69 Lower Eocene rocks ____________________________ _ 35 10. Partial section of Lost Cabin Member of Wind Indian Meadows Formation _________________ _ 35 River Formation, sec. 25, T. 39 N., R. 89 W __ 69 Wind River Formation _____________________ _ 44 11. Partial section of lower part of Wind River Younger Tertiary rocks _________________________ _ 54 Formation, sec. 21, T. 33 N., R. 90 W ______ _ 70 Summary of geologic history and paleogeography ______ _ 55 12. Partial section of upper part of Wind River For- Significance of downfolding in basin tectonics __________ _ 58 mation, sec. 32, T. 33 N., R. 90 W _________ _ 70 Economic geology _________________________________ _ 60 13. Generalized section of lower Eocene and Paleo­ Oil and gas ___________________________________ _ 60 cene rocks, Continental Oil Co. Moneta Hills Coal _________________________________________ _ 11-1 ____________________________________ _ 62 70 Uranium _____________________________________ _ 62 Literature cited _____ ------_______________ ---------- 71 Other commodities _____________________________ _ 63 Index--------------------------------------------- 75 Strati graphic sections ____ ---- ____ - __ -- __________ - __ _ 63 1. Lance and Meeteetse Formations at Castle Gardens ________________________________ _ 63 ILLUSTRATIONS- [Plates are in pocket] PLATE 1. Geologic map of uppermost Cretaceous, Paleocene, and lower Eocene rocks in Wind River Basin. 2. Fence diagram showing stratigraphic relations of uppermost Cretaceous, Paleocene, and lower Eocene rocks in the Wind River Basin. & 3. Correlation of Paleocene and lower Eocene rocks across central part of Wind River Basin. 4. Progressive stages in the structural evolution of the Wind River Basin during the Laramide orogeny. Page Index map of Wyoming _________________________________ -·-_____________________ A3 'w FIGURE 1. 2. Principal sources of geologic mapping data used in this report _________________ -_-_- 4 3. Major physiographic and structural features in central Wyoming____ _ ____________ - 5 4. Sketch map of Wind River Basin showing ~hicknesses and distribution of Meeteetse Formation and Lewis Shale ___ ---------------------------------------------- 12 5. Outcrop of Meeteetse Formation north of Shotgun Butte___ _ ____________________ - 14 6. Correlation of Meeteetse Formation and Lewis Shale, southeastern Wind River Basin_- 15 7. Unconformity between Lance and· Mesaverde Formations along east flank of Alkali Butte anticline ____________________________________ --------_________________ 16 8. Nomenclature and correlation of uppermost Cretaceous, Paleocene, and lower Eocene rocks in the Wind River Basin and adjacent regions in Wyoming_________________ 18 III IV CONTENTS Page FIGURE 9. Isopach map of Lance Formation ____________ -------_____ ----------_______ ------ A19 10. Exposure of Lance and Fort Union Formations northeast of Waltman _ _ _ _ _ _ _ _ _ __ _ _ _ 20 11. Part of Lance Formation at Castle Gardens---------------------,..---------------- 20 12. Isopach map of Fort Union Formation _______ _:__________________________________ 23 13. Exposure of Waltman Shale Member of Fort Union Formation southeast of type section---------------------------------~---------------------------------- 24 14. Isopach map of Waltman Shale Member of Fort Union Formation ____·______________ 25 15. Characteristic electric logs of Waltman Shale Member of Fort Union Formation and associated strat~- _______ - ________________ ---_--- _- _-- __ - _____ - _---- _ _ _ _ _ _ _ _ _ 26 16. Distribution of elements in Waltman Shale Member of Fort Union Formation_ ------ 27 17. Unconformity between Indian Meadows Formation and overturned strata of Mesaverde, Meeteetse, and Fort Union Formations at Twin Buttes _________________________ _ 31 18. Unconformity between Lysite Member of Wind River Formation and nearly vertical strata of Lance and Fort Union Formations at Hells Half Acre __________________ _ 32 19. Unconformity between Wind River and Fort Union Formations north .of Castle Gardens------------------------------------------------------------------- 34 20. An interpretation of geography during Paleocene time in parts of Wyoming and ad- jacent States--------------------------------------------------------------- 35 21. Generalized geology in type area of Indian Meadows Formation ___________________ _ 36 22. Generalized geology of the Badwater Creek area _________________________________ _ 37 23. Outcrops of Paleocene and lower Eocene rocks along west flank of Casper Arch _______ _ 38 24. Sections showing stratigraphic and structural relations of Paleocene and lower Eocene rocks in parts of the Wind River Basin _______________________________________ _ 40 25. Indian Meadows Formation on west side of Shotgun Butte ________________________ _ 41 26. An interpretation of the origin of detached masses of Paleozoic rocks in the Indian Meadows Formation near Twin Buttes _______________________________________ _ 44 27. Wind River Formation overlapping Triassic rocks along north wall of Dinwoody Canyon-------------------------------------------------------------------- 46 28. Prominent badlands in variegated strata of Lysite Member of Wind River Formation at Hells Half Acre _________________________________________________________ _ 50 29. Generalized isopach map of lower Eocene rocks _________________________________ _ 52 3G-34. Wind River Basin- 30. At maximum westward advance of Lewis Sea ____________________________ _ 55 31. Near end of Lance deposition _________________________________________ _ 56 32. During deposition of Waltman Shale Member of Fort Union Formation _____ _ 57 33. At beginning of Wind River deposition---- ______________________________ _ 58 34. At end of Wind River deposition _______________________________________ _ 59 1 1 35. Index map showing lines of section A~ A , plate 4, and section B-B , figure 36 _______ _ 60 1 36. Restored section (B-B ) at end of early Eocene time across southeastern part of Wind River Basin---------------------------------------------------------------- 61 37; Alternate interpretations of crustal movement in central Wyoming _________________ _ 61 38. Evolution of folds in northwestern part of Wind River Basin _______________________ _ 63 TABLES Page TABLE 1. List of geologic sections used in construction of fence diagram, plate 2 _______________ _ A7 2. Fossil collections in the Wind River Basin ____________________________ ._ __________ _ 9 3. Collections of spore and pollen in Wind River Basin________________________________ _ 12 4. Chemical analyses of shale from Waltman Shale and Cannonball Members of Fort Union Formation and average composition of selected samples from the Pierre Shale and Green River Formation ___________________________________________ _ 25 5. X-ray analyses