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Stratigraphy of the Upper Cretaceous Fox Hills Sandstone and Adjacent

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Stratigraphy of the Upper Cretaceous Fox Hills Sandstone and Adjacent Stratigraphy of the Upper Cretaceous Fox Hills Sandstone and AdJa(-erit Parts of the Lewis Sliale and Lance Formation, East Flank of the Rock Springs Uplift, Southwest lo U.S. OEOLOGI AL SURVEY PROFESSIONAL PAPER 1532 Stratigraphy of the Upper Cretaceous Fox Hills Sandstone and Adjacent Parts of the Lewis Shale and Lance Formation, East Flank of the Rock Springs Uplift, Southwest Wyoming By HENRYW. ROEHLER U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1532 Description of three of/lapping barrier shorelines along the western margins of the interior seaway of North America UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1993 U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY Dallas L. Peck, Director Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government. Library of Congress Cataloging-in-Publication Data Roehler, Henry W. Stratigraphy of the Upper Cretaceous Fox Hills sandstone and adjacent parts of the Lewis shale and Lance formation, east flank of the Rock Springs Uplift, southwest Wyoming / by Henry W. Roehler. p. cm. (U.S. Geological Survey professional paper ; 1532) Includes bibliographical references. Supt.ofDocs.no.: I19.16:P1532 1. Geology, Stratigraphic Cretaceous. 2. Geology Wyoming. 3. Fox Hills Formation. I. Geological Survey (U.S.). II. Title. III. Series. QE688.R64 1993 551.7T09787 dc20 92-36645 CIP For sale by USGS Map Distribution Box 25286, Building 810 Denver Federal Center Denver, CO 80225 CONTENTS Page Page Abstract......................................................................................... 1 Stratigraphy Continued Introduction................................................................................... 1 Formations exposed on the east flank of the Rock Springs Description and accessibility of the study area ................. 1 uplift Continued Geographic setting............................................................... 3 Lance Formation ......................................................... 23 Previous investigations....................................................... 4 Type of outcrops ................................................. 23 Acknowledgments................................................................ 4 Composition and thickness................................ 23 Stratigraphy.................................................................................. 4 Paleontology........................................................ 23 Regional stratigraphic relationships.................................. 4 Depositional environments and lithofacies....... 26 Formations exposed on the east flank of the Bay cycles................................................ 27 Rock Springs uplift................................................ 6 Definition....................................... 27 Lewis Shale................................................................ 6 Origin............................................. 27 Type of outcrops ............................................... 6 Stages of development.................. 28 Chemistry of bay waters............... 28 Composition and thickness.............................. 7 Importance of bay cycles in coal Paleontology and age....................................... 7 exploration............................... 31 Depositional environments and lithofacies .... 7 Composition, texture, and color of sandstone beds in the Fox Hills Sandstone................................................... 7 Fox Hills Sandstone and lower part of the Lance Type of outcrops ............................................... 7 Formation.......................................................................... 32 Composition and thickness.............................. 8 Correlation of surface sections and drill holes................... 33 Paleontology and age ....................................... 8 Regional paleogeography of the Fox Hills Sandstone in Depositional environments and lithofacies .... 8 the Rock Springs uplift area during maximum Barrier shoreface.................................... 10 marine transgression ....................................................... 36 Tidal inlets, flood-tidal deltas, and Paleogeography of barrier shorelines Nos. 1-3 of the ebb-tidal deltas ........................ 11 Fox Hills Sandstone on the east flank of the Unnamed ebb-tidal delta in Rock Springs uplift........................................................... 36 barrier shoreline No. 1 ............ 13 Summary and conclusions ............................................................ 39 North inlet..................................... 14 References cited............................................................................. 40 Jim inlet........................................ 14 Appendix A. Lithologic descriptions of measured sections 23, Black Butte inlet........................... 16 116, 149, and 3575 of the upper part of the Ericson South inlet..................................... 18 Sandstone, Almond Formation, Lewis Shale, Fox Hills Salley sound............................................ 19 Sandstone, and lower part of the Lance Formation........... 42 Accretionary swash bars at Jim inlet Appendix B. Core description of U.S. Geological Survey and Salley sound................................ 21 corehole BC No. 1................................................................. 50 Shoreline submergence and marine Appendix C. Lithologic description of measured section 104 trangression............................................... 21 of the upper part of the Lewis Shale, Fox Hills Sandstone, Barrier island models....................................... 22 and lower part of the Lance Formation.............................. 56 ILLUSTRATIONS [Plates are in pocket] PLATE 1. Map of the Rock Springs uplift area, southwest Wyoming, showing locations of measured sections and stratigraphic correlations. 2. Stratigraphic correlation A-A' of outcrops of the lower part of the Lance Formation, Fox Hills Sandstone, and upper part of the Lewis Shale, east flank of the Rock Springs uplift, southwest Wyoming. 3. Columnar section, gamma-gamma density log, and depositional environments, U.S. Geological Survey corehole BC No. 1, east flank of the Rock Springs uplift, southwest Wyoming. 4. Columnar section identifying bay cycles in measured section 104 of the Lance Formation, southwest Wyoming. 5. Surface-subsurface stratigraphic correlations B-B', C-C', D-D', and E-E' of the Fox Hills Sandstone and adjacent formations, east flank of the Rock Springs uplift, southwest Wyoming. in IV CONTENTS Page FIGURE 1. Index map showing location of outcrops of the Fox Hills Sandstone and adjacent formations in the Rock Springs uplift................................................................................................................................................................................... 2 2. Photograph of outcrops of the Lewis Shale, Fox Hills Sandstone, and Lance Formation................................................. 3 3. Photograph of outcrops of the Fox Hills Sandstone and Lance Formation........................................................................ 3 4. Paleogeographic map of the interior Cretaceous seaway of North America during the Maastrichtian Age ................... 5 5. Restored regional cross section of the Fox Hills Sandstone and other Upper Cretaceous formations across northeast Utah and southern Wyoming........................................................................................................................... 6 6-12. Photographs of fossils: 6. Helminthoidea..............................................................................................................................................^ 7 7. Current-oriented oyster shell fragments ................................................................................................................. 8 8. Layer of oyster shells in shoreface deposits............................................................................................................ 8 9. Terebellina.... .............................................................................................................................................................. 9 10. Ophiomorpha ............................................................................................................................................................. 9 11. Cylindrichnus (top view)........................................................................................................................................... 9 12. Cylindrichnus (side view)......................................................................................................................................... 9 13. Diagram showing nomenclature of barrier islands and associated depositional environments and lithofacies.............. 10 14. Generalized columnar section showing nomenclature of shoreface and associated depositional environments and lithofacies........................................................................................................................................................................... 11 15-20. Photographs of outcrops of the Fox Hills Sandstone: 15. Lower shoreface sandstone and shale ..................................................................................................................... 11 16. Very thin, parallel beds of lower shoreface sandstone
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