Stratigraphy of the Harper Ranch Group and Tectonic History of the Quesnel Terrane in the Area of Kamloops, British Columbia
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STRATIGRAPHY OF THE HARPER RANCH GROUP AND TECTONIC HISTORY OF THE QUESNEL TERRANE IN THE AREA OF KAMLOOPS, BRITISH COLUMBIA by Tyler Wayne Beatty B.Sc., University of Western Ontario, 1997 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE In the Department of Earth Sciences 43 Tyler Beatty 2003 SIMON FRASER UNIVERSITY November 2003 All rights reserved. This work may be reproduced in whole or in part with permission of the author APPROVAL Name: Tyler Beatty Degree: Master of Science Title of Thesis: Stratigraphy of the Harper Ranch Group and Tectonic History of the Quesnel Terrane in the Area of Kamloops, British Columbia Examining Committee: Chair: Dr. Diana Allen Associate Professor dr. peter Mustard Senior Supervisor Associate Professor mes MacEachern rvisory Committee Member iate Professor D'r. ~=el Orchard .--- Supervisory Committee Member Geological Survey of Canada Dr. kmes Wn'ger External Examiner Adjunct Professor SFU Earth Sciences Date Approved: November 28, 2003 PARTIAL COPYRIGHT LICENCE I hereby grant to Simon Fraser University the right to lend my thesis, project or extended essay (the title of which is shown below) to users of the Simon Fraser University Library, and to make partial or single copies only for such users or in response to a request from the library of any other university, or other educational institution, on its own behalf or for one of its users. I further agree that permission for multiple copying of this work for scholarly purposes may be granted by me or the Dean of Graduate Studies. It is understood that copying or publication of this work for financial gain shall not be allowed without my written permission. Title of ThesislProjectlExtended Essay: Stratigraphy of the Harper Ranch Group and Tectonic History of the Quesnel Terrane in the Area of Kamloops, British Columbia Author: (signadre) - Tyler Wayne Beatty (Name) -- -(Date) ABSTRACT The late Paleozoic Harper Ranch Group (Harper Ranch Group) of south-central British Columbia is a >3 km thick sedimentary succession consisting mostly of marine siliciclastics and carbonates. In the area of Kamloops, the Harper Ranch Group comprises the oldest rocks of Quesnel Terrane. Here, the Quesnel Terrane comprises three unconformity bound successions of island-arc affinity: the Harper Ranch Group, the Late Triassic Nicola Group, and the Early Jurassic Rossland Group. Each succession records subduction-related volcanism and associated sedimentation. Three new formation-rank stratigraphic units are recognized in the Harper Ranch Group. The clastic Tk'emlups Formation, overlain successively by the predominantly carbonate South Thompson and McGregor Creek formations are all formally defined with type sections and detailed descriptions. The South Thompson Formation records volcanic quiescence, the end of volcano-sedimentary sedimentation of the Tk'emlups Formation, and development of arc flanking carbonates in the Late Mississippian. Pre-Early Permian uplift and erosion of Harper Ranch Group units are implied by the character and lithology of the Permian McGregor Creek Formation, a secondary chert-rich carbonate platform succession. Upper Permian to Middle Triassic rocks are not recognized in the area. The Nicola Group records renewed arc-related volcanism, sedimentation, and plutonism in the Late Triassic. The Rossland Group, represented by conglomerate, agglomerate and undifferentiated volcanics, represents a third, Early Jurassic, island-arc succession. Rocks of the Rossland Group unconformably overlie those of the McGregor Creek Formation. New biostratigraphic data from each of the Harper Ranch, Nicola, and Rossland groups, in concert with map relationships, provide time constraints for the tectonic evolution of Quesnel Terrane. iii For my parents and grandparents. Their support was integral to this achievment. ACKNOWLEDGEMENTS Foremost, I acknowledge the financial and logistical support of the Geological Survey of Canada (GSC), the National Sciences and Engineering Research Council (NSERC Grant to P. Mustard), and Simon Fraser University. I am indebted to my supervisor, Peter Mustard, for providing an environment in which I could complete this project. I thank Michael Orchard for encouraging me to return to academics and for introducing me to the wonderful world of microproblematica. Field research for this project was implemented as part of the Ancient Pacific Margin National Geoscience Mapping Program (NATMAP) project of the GSC. I must thank Bob Thompson for providing this umbrella under which this project could survive. Ted Danner, Wayne Bamber, and Lin Rui are thanked for their expert paleontological skills and moreover their excellent conversation. Charles Henderson helped me hone my skills as a geologist and paleontologist. James MacEachern and J- P Zonneveld taught me the value of sedimentology and ichnology; J-P also taught me to appreciate an Islay. John Jules of the Kamloops Indian Band is thanked for providing access to the bands ancestral land. John Wong of the Canada Lafarge Cement Company was helpful in providing access to the quarry and surrounding land. I especially would like to thank Natalka Allan, Spencer Beatty, and Stephen Haas for their expert field assistance. Finally I would like to thank the grad-crew (and associates), they provided me with friendship, entertainment, understanding, adventure (Slopers), and respect that, if expounded, could fill volumes. Rebecca preceded and endured this oeuvre; I am forever beholden. TABLE OF CONTENTS Approval ................................................................................................................ ii ... Abstract ............................................................................................................... IH Dedication ............................................................................................................iv Acknowledgements ...............................................................................................v Table of Contents ................................................................................................. vi ... List of Figures .....................................................................................................VIII List of Tables ........................................................................................................x CHAPTER 1: INTRODUCTION ............................................................................I Objectives of the Study ............................................................................................ 1 Methods of Study ..................................................................................................... 2 Thesis Format .......................................................................................................... 3 Location ................................................................................................................... 3 General Geology and Previous Work ....................................................................... 5 CHAPTER 2: GEOLOGY AND FORMAL DEFINITION OF THE HARPER RANCH GROUP. KAMLOOPS. BRITISH COLUMBIA ......................................... 9 Abstract .................................................................................................................... 9 Introduction ............................................................................................................ I0 Geologic Setting ..................................................................................................... II Lithostratigraphy.................................................................................................... -14 Harper Ranch Group .............................................................................................. 14 Type area and composite type section ............................................................... 17 Definition ........................................................................................................... 17 Tk'emlups Formation .............................................................................................. 19 Type section and reference section ................................................................... 21 Definition .......................................................................................................... -24 Fauna ................................................................................................................ 28 South Thompson Formation ................................................................................... 29 Composite Type Section .................................................................................... 32 Definition ................................................................................................................ 34 Fauna ................................................................................................................ 44 McGregor Creek Formation ....................................................................................46 Type Locality and Section ..................................................................................48 Definition ........................................................................................................... 51 Fauna ................................................................................................................ 52 Depositional History ..............................................................................................