? Lower and Lower Middle Devonian Rugose Corals of the Central Great Basin GEOLOGICAL SURVEY PROFESSIONAL PAPER 805 Lower and Lower Middle Devonian Rugose Corals of the Central Great Basin By C.W. MERRIAM GEOLOGICAL SURVEY PROFESSIONAL PAPER 805 A stratigraphic-paleontologic study of rugose corals as aids in age determination and correlation of Great Basin Devonian rocks with those of other regions UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1974 UNITED STATES DEPARTMENT OF THE INTERIOR ROGERS C. B. MORTON, Secretary GEOLOGICAL SURVEY V. E. McKelvey, Director Library of Congress catalog-card No. 73-600011 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 - Price $2.85 (paper cover) Stock Number 2401-02488 CONTENTS ±"age Page Abstract ........................................................................................ 1 Coral succession and evolution as related to geologic Introduction ................................................................................ 1 change and faunal migration ........................................ 25 Purpose and scope of investigation.................................. 3 Coral changes at close of Silurian.................................... 27 History of investigation...................................................... 4 Late Silurian and Devonian bursts of rugose Methods of investigation.................................................... 5 coral evolution ......................................................... 28 Acknowledgments .............................................................. 6 Zone D coral burst...................................................... 28 Stratigraphy of central Great Basin Devonian rocks........ 6 Zone F coral burst........................................................ 28 Great Basin Devonian f acies belts and coral Zone I coral burst........................................................ 29 reference sections................................................... 6 Age and correlation of Great Basin Early and early Antelope-Roberts Mountains facies belt.................. 6 Middle Devonian coral zones........................................ 29 Lone Mountain reference section...................... 8 Age and correlation with distant regions. 29 Nevada Formation, unit 1.......................... 8 Coral zone A ..................... ........................ .......... 29 Nevada Formation, unit 2.......................... 8 Coral zone B ................................................................ 29 Nevada Formation, unit 3.................. .. 8 Coral zone C ................................................................ 29 Nevada Formation, unit 4.......................... 8 Coral zone D . ...........-...........................'............. 30 Nevada Formation, unit 5.......................... 9 Correlation with other areas in the Cordilleran Belt.... 30 Devils Gate Limestone................................ 9 North-central Great Basin ........................................ 31 Southern Sulphur Spring Range Northern Sulphur Spring Range...................... 31 reference section...................................... 9 Southern Tuscarora Mountains........................ 31 Beacon Peak Dolomite Member............... 11 Cortez Mountains .............................................. 31 Nevada Formation, unit 1........................... 11 West-central Great Basin.......................................... 31 Nevada Formation, unit 2...................... .. 13 Toiyabe Range .................................................... 31 Sentinel Mountain Dolomite Member.... 13 South-central Great Basin ........................................ 32 Woodpecker Limestone Member.............. 13 Hot Creek Range ................................................ 32 Bay State Dolomite Member.................... 13 Southern Great Basin ................................................ 32 Devils Gate Limestone................................ 15 Ranger Mountains .............................................. 32 Diamond Mountains facies belt................................ 15 Desert Range ...................................................... 32 Beacon Peak Dolomite Member ...................... 15 Northern Panamint Mountains. .. 32 Oxyoke Canyon Sandstone Member................ 15 Funeral Mountains ............................................ 32 Sentinel Mountain Dolomite Member ............ 15 Northern Inyo Mountains.......... ..................... 33 Woodpecker Limestone Member.................. 16 Systematic and descriptive paleontology................................ 33 Bay State Dolomite Member ............................ 16 Classification of Great Basin Early and early Devils Gate Limestone........................................ 17 Middle Devonian Rugosa .............................................. 33 Monitor-Simpson Park facies belt....................... .. 17 Taxonomic interpretation of rugose coral structure...... 34 Rabbit Hill Limestone........................................ 17 Exterior corallum features ........................................ 34 Coral biostratigraphy of the central Taxonomic evaluation of corallum interior Great Basin Devonian .................................................... 17 structures ........................................................ 35 Early and early Middle Devonian coral zones.......... 19 Septa .................................................................... 35 Coral zone A ................................................................ 19 Tabulae ................................................................ 36 Coral zone B .......................................................... ... 20 Dissepiments ...................................................... 36 Coral zone C ................................................................ 20 Stereoplasmic deposits ...................................... 37 Coral zone D ................................................................ 20 Rugose coral symmetry and taxonomy.................... 37 Middle Middle Devonian coral zones.............................. 21 Growth changes and reproductive features............ 37 Coral zone E ................................................................ 21 Variation and dimorphism........................................ 38 Coral zone F ................................................................ 21 Descriptive terms ................................................................ 38 Coral zone G ................................................................ 21 Family Laccophyllidae ...................................................... 38 Late Middle and Late Devonian coral zones.................. 21 Genus Syringaxon ...................................................... 39 Coral zone H................................................................ 22 Family Streptelasmatidae ................................................ 40 Coral zone I.................................................................. 22 Subfamily Siphonophrentinae ........:....................... 41 Biof acies aspects of Devonian coral distribution Genus Siphonophrentis .................................... 41 and zonation .................................................................... 22 Subgenus Breviphrentis ............................ 42 Syringaxon biofacies .......................................................... 23 Genus Nevadaphyllum ...................................... 44 Kobeha biofacies ................................................................ 23 Family Kodonophyllidae .................................................. 44 Papiliophyllum biofacies .................................................. 24 Family Stauriidae .............................................................. 45 Breviphrentis biofacies ...................................................... 24 Genus Dendrostella .................................................... 45 Hexagonaria-Sociophyllum biofacies .............................. 25 Family Halliidae ................................................................ 46 Phillipsastraea biofacies .................................................... 25 Subfamily Halliinae .................................................. 46 in IV CONTENTS Page Page Systematic and descriptive paleontology Continued Systematic and descriptive paleontology Continued Family Halliidae Continued Family Disphyllidae Continued Subfamily Halliinae Continued Genus Hexagonaria .................................................... 60 Genus Aulacophyllum ............................... 46 Subgenus Pinyonastraea .................................. 61 Genus Odontophyllum ............................... 47 Genus Billingsastraea ................................................ 62 Subfamily Papiliophyllinae .............................. 47 Family Cystiphylloidae .................................................... 64 Genus Kobeha ............................................ 47 Genus Cystiphylloides .............................................. 65 Genus Papiliophyllum .............................. 50 Family Digonophyllidae .................................................. 67 Genus Eurekaphyllum .............................. 52 Subfamily Digonophyllinae ...................................... 67 Family Bethanyphyllidae ................................................ 53 Genus Mesophyllum .......................................... 67 Genus Bethanyphyllum ...........................................