INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis arxi dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6" x 9" black and white photographic prints are available for any photographs or illustrations appearing In this copy for an additional charge. Contact UMI directly to order. Bell & Howell Information and Learning 300 North Zeeb Road, Ann Arbor, Ml 48106-1346 USA 800-521-0600 UMI NOTE TO USERS This reproduction is the best copy available. UMI Stratigraphy, Conodont Taxonomy and Biostratigraphy of Upper Cambrian to Lower Silurian Platform to Basin Facies, Northern British Columbia by Leanne Pyle B. Sc., University of Saskatchewan, 1994 A Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of DOCTOR OF PHILOSOPHY in the School of Earth and Ocean Sciences We accept this dissertation as conforming to the required standard , Supervisor (School of Earth and Ocean Sciences) Dr. D. Canil, Departmental Member (School of Earth and Ocean Sciences) Dr. K. M. GUKs, Department^ Member (School of Earth and Ocean Sciences) r. L. Hobson, Departmental Member (Department of Biology) Dr. G. S. N ^ la n , External Examiner (Geological Survey of Canada) © Leanne Pyle, 2000 University of Victoria All rights reserved. This dissertation may not be reproduced in whole or in part, by photocopying or other means, without the permission of the author. il Supervisor: C. R. Bames A b s t r a c t This study establishes the stratigraphie framework and conodont biostratigraphy of Lower Paleozoic strata of the Northern Canadian Cordilleran Miogeocline, which document a non-passive tectonic evolution of the rifted margin of Laurentia. Only a few reconnaissance stratigraphie studies have been conducted previously in the study area. Nine key sections span an east-west transect from the Macdonald Platform to the Kechika Trough (platform-miogeocline-basin) and 3 key sections comprise a transect across the parautochthonous Cassiar Terrane. Over 12 000 m of strata from the Kechika and Skoki formations and Road River Group in northeastern British Columbia were measured and described, from which a total of 405 conodont samples (4-5 kg each) were taken. A total of 39 526 conodonts have been used to refine the Upper Cambrian to Lower Silurian conodont biostratigraphy across the transect. The stratigraphy is revised to divide the Kechika Formation (late Cambrian to early Arenig in age) into 5 formal members: Lloyd George, Quentin, Grey Peak. Haworth and Mount Sheffield members. The Skoki Formation (early to late Arenig in age) comprises 3 new formal members defined as: Sikanni Chief. Keily and Redfem members. The Road River Group is divided into 3 new formations: Ospika (early Arenig to Llanvim in age), Pesika (Lower Silurian in age) and Kwadacha (formerly the Silurian Siltstone). The Ospika Formation is further subdivided into 5 formal members: Cloudmaker, Finlay Limestone, Chesterfield, Finbow Shale and Ware. Conodonts of Late Cambrian to Early Silurian age are described taxonomically from the Kechika, Skoki, Ospika and Pesika formations across the transect. A total of 39 526 identifiable conodonts recovered from 142 productive samples indicate high species diversity and abundance in shallow water facies and less diversity and abundance with in deeper water facies. Elements are moderately to well preserved, typically with a colour alteration index (CAl) of 3-5. A total of 197 species, representing 73 genera are identified and illustrated among which 6 new genera and 39 new species are described. Fifteen of the 39 new species had too little material and were described in open nomenclature. The new genera are Graciloconus, Kallidontus, Planusodus and 3 new genera (A, B. C) treated in open Ill nomenclature. The new species are Acodus kechikaensis n. sp., Acodus neodeltaiiis n. sp., A. quentinensis n. sp., A. warenesis n. sp., Cordylodus delicatus n. sp., Colaptoconus greypeakensis n. sp., IDiaphorodns n. sp., Drepanoistodus minutus n. sp., Graciloconus concinnus n. gen. n. sp., Kallidontus serratus n. gen. n. sp., K. nodosus n. gen. n. sp., K. princeps n. gen. n. sp., Laurentoscandodus sinuosus n. sp., Macerodus cristatus n. sp., M limatus n. sp., Microzarkodina n. sp., Oepikodus n. sp., Oistodus n. sp., Paroistodus n. sp., Planusodus gradus n. gen. n. sp., IPrioniodus n. sp., Proioprioniodus n. sp., Rossodus kwadachaensis n. sp., R. muskwaensis n. sp., R. sheffieldensis n. sp.. R. subtilis n. sp., Scolopodus amplus n. sp., Striatodonius strigatus n. sp., Triangulodus akiensis n. sp., Tricostaius infundibulum n. sp., T. terilinguis n. sp., 3 unnamed new genera and 3 new species and 5 new species of Drepanoistodus (A, B. C, D, E). The conodont zonation for Upper Cambrian to Lower Silurian strata is refined, using Sections 4, 5, 13 and Grey Peak as reference sections. It allows close dating of stratigraphie boundaries. The oldest zones in the Kechika are cosmopolitan and include the Eoconodontus Zone (upper Cambrian), Cordylodus proavus and Cordylodus lindstromi zones (uppermost Cambrian) and lapetognathus Zone (base of Tremadoc). Ten higher zones are recognized and redefined for shallow water platform facies containing faunas of the Midcontinent Realm. Four of these are new {Polycostatus falsioneotensis, Rossodus tenuis, Scolopodus subrex and Acodus emanualensis zones) and 10 new subzones are established. Those for the Kechika Formation include, in ascending order, the Polycostatus falsioneotensis Zone (lower Tremadoc). Rossodus tenuis Zone (lower Tremadoc); Rossodus manitouensis Zone with R. muskwaenesis and R. sheffieldensis subzones (middle Tremadoc), Low diversity interval (upper Tremadoc), Scolopodus subrex Zone with Graciloconus concinnus and Colaptoconus bolites subzones (lower Arenig) and Acodus kechikaensis Zone with Kallidontus serratus. Diaphorodus russoi and Kallidontus nodosus subzones (lower Arenig). Those for the Skoki Formation include the Oepikodus communis Zone with Tropodus sweeti, Bergstroemognathus extensus and Juanognathus variabilis subzones (middle Arenig). The O. communis Zone spans the Kechika-Skoki boundary and the uppermost Kechika lies within the lowermost part o f the O. communis zone underlying the T. sweeti Subzone. The Skoki Formation also contains the Jumudontus gananda Zone (middle Arenig) and IV Tripodus laevis Zone (upper Arenig). The Phragmodus undatus Zone (Upper Ordovician) lies within the Road River Group in the Cassiar Terrane. Thirteen deep water zones are recognized for basinal facies containing faunas of predominantly the North Atlantic Realm. Five new zones are established {Drepanoistodus nowlani, Acodus deltatus, Paracordylodus gracilis, Paroistodus horridus and Dzikodus tableheadensis zones) and one new subzone within the P. gracilis Zone is proposed. Those within the Kechika Formation include Cordylodus angulatus Zone (lower Tremadoc), Paltodus deltifer Zone (middle Tremadoc), Drepanoistodus nowlani Zone (middle Tremadoc), Acodus deltatus Zone, (middle Tremadoc), Paroistodus proteus Zone (upper Tremadoc), Paracordylodus gracilis Zone with Oelandodus elongatus Subzone (upper Tremadoc) and Prioniodus elegans Zone (base of Arenig). Those within the Skoki and Ospika formations include Oepikodus evae Zone (Skoki Formation, middle Arenig), Paroistodus originalis Zone (Skoki and Ospika formations, upper Arenig), Paroistodus horridus and Dzikodus tableheadensis zones (both within the Ospika Formation, lower Llanvim). The Amorphognathus tvaerensis Zone lies within the Road River of the Cassiar Terrane (Upper Ordovician). The Distomodus staurognathoides Zone lies within the Pesika Formation (middle Llandovery). The conodont faunas therefore provide detailed temporal constraints for the stratigraphie framework. Some evolutionary remarks are made for selected species involved in radiations, especially in the Tremadoc and Arenig, that are useful in further refining the standard Midcontinent Realm zonation. The Midcontinent Realm conodont faunas are used for regional correlations within North America and those of the Atlantic Realm provide calibration on an interregional scale, for example, with Baltica. Dr. C. R. Bames, Supervisor (School of Earth and Ocean Sciences) Dr. D. Canil, Departmental Member (School of Earth and Ocean Sciences) _______________________________________________ Dr. K. M. Gillis, Departmental Member (School of Earth and Ocean Sciences) — ----------------------------------------------------------------------------------------------------------------------------------------------- Dr. L. Hobson, Departmental Member (Department
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