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Early Paleozoic Biochronology of the Great Basin, Western United States

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Early Paleozoic Biochronology of the Great Basin, Western United States Early Paleozoic Biochronology of the Great Basin, Western United States Michael E. Taylor, Scientific Editor U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1579 Chapter titles are listed on volume contents page UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1997 CONTENTS I CONTENTS [Letters designate chapters] A. The Ibexian, Lowermost Series in the North American Ordovician By Reuben J. Ross Jr., Lehi F. Hintze, Raymond L. Ethington, James F. Miller, Michael E. Taylor, and John E. Repetski With a section on Echinoderm Biostratigraphy By James Sprinkle and Thomas E. Guensburg B. An Ibexian (Lower Ordovician) Reference Section in the Southern Egan Range, Nevada, for a Conodont-based Chronostratigraphy By Walter C. Sweet and Celeste M. Tolbert C. Upper Ordovician–Silurian Macrofossil Biostratigraphy of the Eastern Great Basin, Utah and Nevada By Peter M. Sheehan and Mark T. Harris III The Ibexian, Lowermost Series in the North American Ordovician By Reuben J. Ross Jr., Lehi F. Hintze, Raymond L. Ethington, James F. Miller, Michael E. Taylor, and John E. Repetski With a section on ECHINODERM BIOSTRATIGRAPHY by James Sprinkle and Thomas E. Guensburg EARLY PALEOZOIC BIOCHRONOLOGY OF THE GREAT BASIN, WESTERN UNITED STATES U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1579–A UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1997 U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY Gordon P. Eaton, Director For sale by U.S. Geological Survey, Information Services Box 25286, Federal Center Denver, CO 80225 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 CONTENTS Abstract.................................................................................................................................. 1 Introduction ........................................................................................................................... 1 Ibexian Series Type Area and Sections ......................................................................... 2 Acknowledgments ......................................................................................................... 3 Definition of the Ibexian Series............................................................................................. 3 Lithostratigraphy ................................................................................................................... 5 Construction of the Composite Stratotype .................................................................... 6 Notch Peak Formation........................................................................................... 7 Hellnmaria and Red Tops Members.............................................................. 7 Lava Dam Member........................................................................................ 7 House Limestone ................................................................................................... 8 Fillmore Formation................................................................................................ 8 Basal Ledge-forming Limestone Member (1)............................................... 8 Slope-forming Shaly Siltstone Member (2) .................................................. 9 Light-gray Ledge-forming Member (3)......................................................... 10 Brown Slope and Ledge Member (4) ............................................................ 10 Calcarenite Member (5)................................................................................. 10 Calathium Calcisiltite Member (6)................................................................ 11 Wah Wah Limestone ............................................................................................. 11 Ibexian Biostratigraphy .........................................................................................................11 Introductory Statement .................................................................................................. 11 Pre-Ibexian Faunal Zones.............................................................................................. 13 Ibexian Faunal Zones and Chronostratigraphy.............................................................. 14 Ibexian Stages and Trilobite Zones ....................................................................................... 14 Skullrockian Stage (New).............................................................................................. 14 Eurekia apopsis Zone ............................................................................................ 14 Missisquoia Zone................................................................................................... 14 Symphysurina Zone (=Zones A and B, Revised) .................................................. 15 Bellefontia-Xenostegium Zone (=Zone B in Part) ................................................. 16 Paraplethopeltis Zone (=Zone C) ......................................................................... 16 Stairsian Stage (New) .................................................................................................... 17 Leiostegium-Kainella Zone (=Zone D) ................................................................. 17 Tesselacauda Zone (=Zone E)............................................................................... 17 Rossaspis superciliosa Zone (=Zone F) ................................................................ 18 Tulean Stage (New) ....................................................................................................... 18 Hintzeia celsaora Zone (=Zone G-1) .................................................................... 18 Protopliomerella contracta Zone (=Zone G-2)..................................................... 19 Blackhillsian Stage (New)............................................................................................. 19 Trigonocerca typica Zone (=Zone H) ................................................................... 19 Presbynileus ibexensis Zone (=Zone I) ................................................................. 20 Pseudocybele nasuta Zone (=Zone J).................................................................... 20 Hesperonomiella minor Zone (=“Zone K” of Hintze, 1953) ................................ 20 Whiterockian Series............................................................................................................... 21 Rangerian Stage (New).................................................................................................. 21 Paralenorthis-Orthidiella Zone (=Zone L) ........................................................... 21 Conodont Zones..................................................................................................................... 22 Introductory Statement .................................................................................................. 22 Pre-Ibexian Conodont Zones......................................................................................... 22 Ibexian Conodont Zones................................................................................................ 23 VI VI CONTENTS VII Cordylodus proavus Zone (=Fauna A, Lower Part).............................................. 23 Cordylodus intermedius Zone (=Fauna A, Upper Part)........................................ 23 Cordylodus lindstromi Zone (=Fauna B, Lower Part) .......................................... 23 Iapetognathus Zone (New) (=Fauna B, Middle Part) ........................................... 23 Cordylodus angulatus Zone (=Fauna B, Upper Part) ........................................... 24 Rossodus manitouensis Zone (=Fauna C)............................................................. 24 Low Diversity Interval (=Fauna D, Lower Part)................................................... 24 Macerodus dianae Zone (New) (=Fauna D, Middle Part).................................... 25 Acodus deltatus/Oneotodus costatus Zone (New) (=Fauna D, Upper Part) ......... 25 Oepikodus communis Zone (=Fauna E, Lower Part) ............................................ 25 Reutterodus andinus Zone (New) (=Fauna E, Middle Part) ................................. 26 Whiterockian Conodont Zones ..................................................................................... 26 Tripodus laevis Zone (New) (=Fauna E, Upper Part) ........................................... 26 Graptolite Correlations.......................................................................................................... 27 Ibexian Graptolites........................................................................................................ 27 Anomalies and Correlations.......................................................................................... 28 Historical Perspective............................................................................................................ 28 Background and Appeals for Tradition......................................................................... 28 Alternative Viewpoints ................................................................................................. 29 Geographic Perspective......................................................................................................... 29 North America............................................................................................................... 29 Utah and
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