AN ABSTRACT OF THE THESIS OF GEORGE WARNER KENDALL for the degreeMaster of Science (Name of student) in Geology presented on February 14, 1975 (Major department) (Date) Title: SOME ASPECTS OF LOWER ANDMIDDLE DEVONIAN STRATIGRAPHY IN EUREKA COUNTY, NEVADA Redacted for Privacy Abstract approved: D . G. Johnson During much of the Early and MiddleDevonian, dolomite was deposited in shallow restricted environmentsin eastern Nevada, and limestone was deposited in norrnal shallowt*}^ marine environments in central Nevada.The dolomite was deposited on a nearsea-level carbonate mud flat, and the limestone wasdeposited on a continental margin shelf.Lithofacies boundaries trend approximatelynorth- south and pass through central EurekaCounty, Nevada.The transi- tion zone in Eureka County movedonshore and offshore with changes in sea level and sedimentation.Neither the McColley Canyon-Denay nomenclature of western Eureka County northe Sevy-Simonson nomenclature of eastern Nevada isappropriate for rocks deposited in the transition zone.Tongues of Sevy Dolomite andMcColley Canyon Formation require that partsof both nomenclatures be recog- nized.Deposition of dark subtidaldolomite in the transition zone requires that a new formationbe named: SadlerRanch Formation. Significant late Emsian and early Eifelian eventsin central Eureka County include:1) westward progradation of the Sevytidal flat (late Bartine time); 2) eastward transgressionand deposition of the Bartine Tongue (early Coils Creek time);3) development of a southward prograding barrier bar during earlyOxyoke Canyon time (Quartzose Member of the Oxyoke CanyonFormation); 4) deposition of the Sadler Ranch Formation (late CoilsCreek and early Denay times); and 5) westward progradation ofthe Coarse Crystalline Member of the Oxyoke Canyon Formation(late Oxyoke Canyon time). The character of the edge of the carbonateplatform in Nevada changed from mid- Emsian to early Eifeliantime.During the mid to late Emsian, the Bartine Member of the McColley Canyon Formation was deposited in shallow water over abroad area of the shelf.Later, several lithofacies were deposited in the same area.Shallow facies "migrated" offshore, and deep facies"migrated" shoreward.The result was a sedimentation-induced steepeningof the shelf gradient by early Eifelian time. Some Aspects of Lower and Middle Devonian Stratigraphy in Eureka County, Nevada by George Warner Kendall A THESIS submitted to Oregon State University in partial fulfillment of the requirements for the degree of Master of Science Commencement June 1975 APPROVED: Redacted for Privacy Assoate Professor of Geo lo in charge of major Redacted for Privacy C,iairman of the Department of Geology Redacted for Privacy Dean of Graduate School Date thesis is presented February 14, 1975 Typed by Opal Grossnicklausfor George Warner Kendall ACKNOWLEDGMENTS Many people contributed to thethoughts expressed in this thesis, and I cannot thank them allhere. Dr. J.G. Johnson is especially appreciatedfor his stimulating discussions and wealth of knowledge.The intellectual environment he cultivates was essential to thecompletion of the project. Dr. A. R. Niem critically readthe manuscript and offered valuable criticisms.Dr. M. A. Murphy of theUniversity of Cali- fornia discussed Devonian sedimentationand stratigraphy with the writer.Dr. C. A. Nelson, also of theUniversity of California, provided a geologic map of part of theSulphur Spring Range.Dr. Gilbert Klapper of the Universityof Iowa made conodont age deter- minations essential to the thesis.Dr. C. Kent Chamberlain ofOhio University made some helpfulenvironmental determinations on the basis of burrows. Mary Fisher kindly draftedseveral figures and columnar sections.Claudia DuBois graciously andpatiently prepared the numerous conodontsamples. Walt Niebuhr, Roy Smith,Dick Flory, Bill Koch, DaveRohr, and Pete Isaacson allcontributed through many interestingdiscus- sions. And the joy of living providedthe impetus to write this crazy thing. TABLE OF CONTENTS INTRODUCTION 1 Geologic Setting 1 Purpose 3 Previous Work 4 Location and Accessibility 5 Methods of Investigation 8 FORMATIONAL NOMENCLATURE 11 SEVY DOLOMITE 14 General Statement 14 Diamond and Pirion Ranges 17 Basal Quartzite 17 Middle Dolomite 18 Upper Quartzose Unit 23 Mahogany Hills 29 Sulphur Spring Range 31 Transitional Unit 32 Upper Quartzose Unit 38 Age and Correlation 49 BAR TINE TONGUE OF THE McCOLLEYCANYON FORMATION 52 General Statement 52 Lower Limy Dolomite 56 Middle Limestone 58 Upper Limy Dolomite 73 Combined Upper and Lower Units of thePirion and Diamond Ranges 73 Age and Correlation 79 SADLER RANCH FORMATION 82 General Statement 82 Lower Dolomite 85 Middle Crinoidal Dolomite 98 Upper Dolomite 102 Age and Correlation 105 OXYOKE CANYON FORMATION 112 General Statement 112 Quartzose Member 112 Diamond Range 116 Outcrop Character 116 Thin Section Description 118 Pion Range 121 Outcrop Character 121 Thin Section Description 124 Depositional Environment 125 Coarse Crystalline Member 130 Outcrop Character 130 Thin Section Description 137 Depositional. Environment 138 Age and Correlation 140 SEDIMENTARY PETROLOGY 143 Grain Size Analysis 143 Heavy Mineral Analysis 148 Organic Carbon Content 149 Provenance 150 GEOLOGIC HISTORY 154 164 CONCLUSIONS REFERENCES CITED 167 APPENDIX I 174 APPENDIX II 177 APPENDIX III 190 APPENDIX IV 193 195 APPENDIX V 197 APPENDIX VI APPENDIX VII 199 (in pocket) PLATES 1-21 LIST OF FIGURES Figure Page 1. Index map of Eureka County, Nevada,showing major geographic features.Outlined areas are Devonian outcrops. 6 2. Index map of Eureka County, Nevada,showing the locations of sections studied.Map areas are shown in green. 7 3. Correlation chart for part of the Lower andMiddle Devonian of Nevada. 12 4. Lithofacies distribution during mid-Kobeh time. 15 16 5. Lithofacies distribution during mid-Bartinetime. 6. Transitional zone of upper Sevy Dolomite inOxyoke Canyon.Oxyoke Canyon Formation is in upperright corner of photo. 25 7. Vertical sand-filled burrows in the upper partof the Sevy Dolomite in Oxyoke Canyon. 25 8. Mudstone covered ripples in the quartzose upperunit of the Sevy Dolomite in Oxyoke Canyon. 27 9. Bartine Tongue interbed in the quartzose upperunit of the Sevy Dolomite in Oxyoke Canyon. 27 10, Lithofacies distribution during late Bartinetime. 30 11. Conformable contact between the BartineMember of the Mc Colley Canyon Formation andthe overlying transitional unit of the Sevy Dolomite inthe Sulphur Spring Range. 33 12. Photomicrograph of intraclasts from thetransitional unit of the Sevy Dolomite in theSulphur Spring Range. 33 13. Photomicrograph of a silicified brachiopodshell in the transitional unit of the Sevy Dolomite inthe Sulphur Spring Range. 37 Figure Page 14. Hand sample of a quartz arenite bed in the upperunit of the Sevy Dolomite in the SulphurSpring Range showing basal scour and graded bedding. 41 15. Facies tract model for deposition of theBartine Limestone and upper tongue of the SevyDolomite in central Eureka County, Nevada.No vertical scale. 46 16. Successive steps in the westward progradationof the Sevy tidal flat.Depths are approximate. 48 17. Schematic diagram of facies relationships inthe Bartine Tongue (early Coils Creek age).No vertical or horizontal scale. 54 18. Lithofacies distribution during early CoilsCreek time. 55 19. Typical exposure of the middle limestoneof the Bartine Tongue in the Sulphur Spring Range. 61 20. Slabbed sample of the middle limestone ofthe Bartine Tongue showing variations in texture. 61 21. Weathered surface of a stromatoporoidboundstone lense from the middle limestone of theBartine Tongue (Sadler Ranch Section). 64 22. Slab through a sediment "smothered"Favosites sp. from the middle limestone of the BartineTongue (Telegraph Canyon Section). 64 23. Poorly exposed lense in the middle limestoneof the Bartine Tongue (Telegraph CanyonSection). 67 24. Photomicrograph of microlaminated limemuds tone overlain by packs tone with patchy sparrycement, Sample from the Bartine Tongue atTelegraph Canyon. 67 25. Facies tract model for depositionof the Bartine Tongue and corresponding part of theSevy Dolomite in central Eureka County, Nevada.No vertical scale. 72 Figure Page 26. Laminated limy dolomite mudstone from the Bartine Tongue (Oxyoke Canyon Section). 77 27. Lithofacies distribution during early Sadler Ranch and Oxyoke Canyon time. 84 28. Sharp contact between the Bartine Tongue andSadler Ranch Formation in Telegraph Canyon.Note the clast of Bartine Tongue lithology in the overlyingSadler Ranch Formation. 86 29. Slab of KDL-183 showing burrows, silicifiedbrachi- opods, and siliceous fracture fillings. 89 30. Photomicrograph of KDL-183 showing a silicified brachiopod in a pseudospar matrix. 89 31. Facies tract model for deposition of theSadler Ranch Formation, Quartzose Member of the Oxyoke Canyon Formation, and upper Sevy Dolomite in centralEureka County,No vertical scale. 97 32. Typical exposure of the crinoidal unit of theSadler Ranch Formation in the Sulphur Spring Range. 100 33. Loading at the base of a crinoidal packstone bedin the upper dolomite of the SadlerRanch Formation. 100 34. Contact between the Sadler Ranch Formation andthe overlying Coarse Crystalline Member of theOxyoke Canyon Formation (Sadler Ranch Section). 103 35. Generalized cross section perpendicular todeposi- tional strike during mid-Oxyoke Canyon time.Five miles is hypothesized distance betweenUnion Mountain and Telegraph Canyon prior to faultingin Bruffey Canyon.Depths are in feet and are approximate. 108