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Geology of the Bunkervilie Section of the Virgin

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Geology of the Bunkervilie Section of the Virgin Geology of the Bunkerville section of the Virgin Mountains, Nevada and Arizona Item Type text; Dissertation-Reproduction (electronic); maps Authors Seager, William R. Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 24/09/2021 23:17:31 Link to Item http://hdl.handle.net/10150/565133 GEOLOGY OF THE BUNKERVILIE SECTION OF THE VIRGIN MOUNTAINS, NEVADA AND ARIZONA by William Ralph Seager A Dissertation Submitted to the Faculty of the DEPARTMENT OF GEOLOGY In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 1966 THE UNIVERSITY OF ARIZONA GRADUATE COLLEGE I hereby recommend that this dissertation prepared under my direction by ______ William Ralph Seager_________________________ entitled __________ Geology of the Bunkerville Section of the __________ Virgin Mountains; Nevada and Arizona________ be accepted as fulfilling the dissertation requirement of the degree of _________ Doctor of Philosophy_________________________ Dissertation Direct^ Date After inspection of the dissertation, the following members of the Final Examination Committee concur in its approval and recommend its acceptance:* 4*- 2/ - fafo 4-Zf-iC *This approval and acceptance is contingent on the candidate's adequate performance and defense of this dissertation at the final oral examination. The inclusion of this sheet bound into the library copy of the dissertation is evidence of satisfactory performance at the final examination. STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at the University of Arizona and is deposited in the University Library to be made available to borrowers under rules of the Library, Brief quotations from this dissertation are allowable without special permission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or re­ production of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his judgment the proposed use of the material is in the in­ terests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED: ACKNOWLEDGMENTS The writer is indebted to Dr. Brans B. Mayo for his advice and helpful suggestions in the field and for critically reviewing the manuscript. Pertinent comments and criticism from Dr. Joseph F. Schreiber, Jr., Dr. Richard Wilson, Dr. Willard Pye, Dr. Edgar McCulloch and Dr. Spencer Titley greatly aided in preparation of the report. The Pan American Petroleum Corporation granted the writer leave of absence and provided funds and equipment which defrayed, in part, the expenses incurred during field work and preparation of the report. Drafting excellence of the map and cross sections is due to the skill of Earl Rhodes of the drafting department of Pan American Petroleum Corporation, All of this generous aid is gratefully acknowledged. Special appreciation is due my wife, D. D. Seager, whose en­ couragement and long hours in the field and at the typewriter made this dissertation possible. Finally, we both would like to acknowledge the 1 V graciousness and hospitality of the people of Bunkerville, Nevada, who made our stay there truly enjoyable. iii TABLE OF CONTENTS Page - U S T OF ILLUSTRATIONS ..................... .. ; . ^ , vi LIST OF TABLES. ................. ................ .. , . viii ABSTRACT. ........... .................. .. ........... ..... x./.;'!*. INTRODUCTION. ............................. ........-I Location and Accessibility . ■ . ^ . -. '1 ; ' Purpose and Scope. ............................... .. • . .' 3 Method of Investigation................ .. 4 Previous Work........ .. .... .... .... .5 Physical Features. ................. .. i 5" STRATIGRAPHY. ............................... .......... General Features . ............. .. 8. Precambriam Rocks. .......... ....... .12 Cambrian Formations............ ................ .. 13 General .... ................ ...... 1 3 Prospect Mountain Quartzite ................. 1 5 Pioche Shale. .......... ........ 16 Lyndon Limestone. ..................... .. 17 . Chisholm Shale. ............... .19. Peasley Limestone .......... .20 Cambrian Undifferentiated .......... 22 Pogonip Group (Ordovician) ..................... ♦ 25 Muddy Peak Limestone (Devonian). .... 27 Monte Cristo Group (Mississippian) ........ .30 Callville Limestone (Mississippian?-Pennsylvanian) . 32 Permian Formations .................. ...... .35 G e n e r a l.......... ........................ .. 35 Pakoon Limestone. .............. 35 Queantoweap Sandstone . .37 Hermit Formation. .............. 39 Coconino Sandstone............ .. 41 Toroweap Formation. ........... .. .42 Kaibab Limestone. .............. .44 Triassic Formations........ ...................... 45 General . ............ ........... ♦ 45 Mdenkopi Formation. ............. .. .45 Chlnle Formation. ........................... Aztec Sandstone (Triassic? and Jurassic) . • . * * 4 8 iv V TABLE OF CONTENTS— Continued ..... Page Cretaceous Formations. ..................... • . 49 G e neral.....................................................49 Willow Tank Formation...................................... 49 Baseline Sandstone.................. $0 Overton Fanglomerate (Cretaceous or Tertiary).................. 5 1 Tertiary Formations. ..... ................................. 52 G e n eral................................................... 5 2 Horse Spring Formation...................... 52 Muddy Creek Formation ........................... ..... 53 Bunkerville Ridge Fanglomerate (Pliocene ?) .......... 55 Recent Deposits............................................. .. 58 STRUCTURE ............................................................. 59 Regional Setting ................................................ 59 General Features ..................................... 62 Structure of the Precambrian R o c k s .................... .. 63 Laramide (?) Structure . ......................................... 65 Origin. ................... 70 Dating of Structural Events ................................ 72 Tertiary Structure .......... .......... ......... 73 High Angle Normal Faults................ 73 Decollement and Glide Faults................................ 76 Low Angle Normal Faults ................ 8 6 Dating of Structural Events ................................ 88 Structural Synthesis ........................................... 89 APPENDIX - measured sections.......................................... 92 Bunkerville Ridge Section........................................ 92 Whitney Pockets Section.................. 106 Tramp Ridge Section.................. Ill Tom and Cull Wash Section............ 117 Lime Kiln Canyon S e c t i o n ....................................... 319 REFERENCES............................................................ 121 LIST OP ILLUSTRATIONS Figure Page 1. Index M a p .............. .. ..................... ............ 2 2. Upper Cretaceous and Tertiary strata at Tom and Cull Wash, Arizona................ 56 3. Bunkerville Ridge Fanglomerate one mile northwest of ' Hen Spring on Bunkerville Ridge............ 5 6 4. a, b, c. Evolution of overthrusting in the Cougar Canyon area.......... 6 9 5. Major Laranri.de (?) overthrust exposed in south wall of Cougar Canyon ............ 71 6. Decollement fault exposed at northwestern corner of Virgin Peak Block............ 79 7. Gravity glide block just south of Sheep Canyon................ 81 8. Gravity glide block just north of Sheep Canyon................ 81 9. Field sketch of gravity glide block north of Cave Wash on Bunkerville Ridge............ 84 10. Field sketch of gravity glide block south of Sheep Canyon on Bunkerville Ridge, ...............................84 11. Field -sketch of faulted glide blocks on Bunkerville Ridge near mouth of Sheep Canyon . ........... .. 84 12. Klippe of imbricated Monte Cristo Group and Callville limestone on strongly overturned Pakoon, Queantoweap, and Hermit beds at mouth of Cabin Canyon ............ .. ....................... .. ... 86 13. Low angle normal fault at the southern end of Tramp Ridge in the Southern Virgin Mountains............ .. 88 14. Geologic map of the central Virgin Mountains, Nevada and A r i z o n a ........ ................ .. .in pocket 15. Structure sections A-A* through H-H'.......... .in pocket vii LIST OF ILLUSTHATIOSS— Continued Figure Page 16. Structure sections I-I ’ through L-L*........ .. .in pocket 17. Stratigraphic cross section of; the Paleozoic , strata In the Virgin Mountain area,.............. Arizona-Hevada ......................... .... .in pocket LIST OF TABLES Table Page 1. Formations'of the Virgin Mountain Area, Nevada and Arizona 10, 11 viii ABSTRACT The Northern Virgin Mountains of northwestern Arizona and adjacent Nevada are an arc-shaped anticlinal uplift that contains marine Paleozoic platform carbonate rocks flanking a central core of well-foliated Precam- brian metamorphic rocks. Except for strong truncation of Ordovician and Cambrian beds toward the southeast, and marked facies changes in the Mis- sissippian System, Paleozoic formations display little lithologic varia­
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