Sedimentary Petrology, Depositional Environment, and Tectonic
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Western Washington University Western CEDAR WWU Graduate School Collection WWU Graduate and Undergraduate Scholarship Fall 1985 Sedimentary Petrology, Depositional Environment, and Tectonic Implications of the Upper Eocene Quimper Sandstone and Marrowstone Shale, Northeastern Olympic Peninsula, Washington William E. (William Ernst) Rauch Western Washington University Follow this and additional works at: https://cedar.wwu.edu/wwuet Part of the Geology Commons Recommended Citation Rauch, William E. (William Ernst), "Sedimentary Petrology, Depositional Environment, and Tectonic Implications of the Upper Eocene Quimper Sandstone and Marrowstone Shale, Northeastern Olympic Peninsula, Washington" (1985). WWU Graduate School Collection. 741. https://cedar.wwu.edu/wwuet/741 This Masters Thesis is brought to you for free and open access by the WWU Graduate and Undergraduate Scholarship at Western CEDAR. It has been accepted for inclusion in WWU Graduate School Collection by an authorized administrator of Western CEDAR. For more information, please contact [email protected]. WESTERN WASHINGTON UNIVERSITY Bellingham, Washington 98225 • [206] 676-3000 MASTER'S THESIS In presenting this thesis in partial fulfillment of the requirements for a master's degree at Western Washington University, I agree that the Library shall make its copies freely available for inspection. I further agree that extensive copying of this thesis is allowable only for scholarly purposes. It is understood, however, that any copying or publication of this thesis for commercial purposes, or for financial gain, shall not be allowed without my written permission. Signature Date ^ j I9S5 MASTER'S THESIS In presenting this thesis in partial fulfillment of the requirements for a master's degree at Western Washington University, I grant to Western Washington University the non-exclusive royalty-free rightto archive, reproduce, distribute, and display the thesis in any and all forms, including electronic format, via any digital library mechanisms maintained by WWU. I represent and warrant this is my original work and does not infringe or violate any rights of others. I warrant that I have obtained written permissions from the owner of any third party copyrighted material included in these files. I acknowledge that I retain ownership rights to the copyright of this work, including but not limited to the right to use all or part of this work in future works, such as articles or books. Library users are granted permission for individual, research and non-commercial reproduction of this work for educational purposes only. Any further digital posting of this document requires specific permission from the author. Any copying or publication of this thesis for commercial purposes, or for financial gain, is not allowed without my written permission. Date: SEDIMENTARY PETROLOGY, DEPOSITIONAL ENVIRONMENT, AND TECTONIC IMPLICATIONS OF THE UPPER EOCENE QUIMPER SANDSTONE AND MARROWSTONE SHALE, NORTHEASTERN OLYMPIC PENINSULA, WASHINGTON A Thesis Presented to the Faculty of Western Washington University In Partial Fulfillment of the Requirements for the Degree Master of Science by WILLIAM E. RAUCH December, 1985 SEDIMENTARY PETROLOGY, DEPOSITIONAL ENVIRONMENT, AND TECTONIC IMPLICATIONS OF THE UPPER EOCENE QUIMPER SANDSTONE AND MARROWSTCNE SHALE, NORTHEASTEPN OLYMPIC PENINSULA, WASHINGTON by WILLIAM E. RAUCH Accepted in Partial Completion of the Requirements for the Degree Master of Science Advisory Committee Chairperson FRONTISPIECE The finest workers in stone are not copper or steel tools, but the gentle touches of air and water working at their leisure with a liberal allowance of time. Henry David Thoreau ABSTRACT The Upper Eocene ^Refugian) Quimper Sandstone and overlying Marrowstone Shale document approximately 300 meters of sediment deposited in a tectonical ly active, shal low marine area during a transgression. The Quimper Sandstone and Marrowstone Shale can be roughly divided into three facies, representing deposition from outer shore face and inner shelf to offshore or outer shelf. Petrographic analysis of the Quimper Sandstone and Marrowstone Shale indicates geography and hydrodynamic conditions were responsible for a slight petrologic trend in composition such as more feldspar and lithic grains in the lower energy facies. The sandstones are lithic and feldspathic arenites and wackes with abundant feldspars and volcanic lithic fragments. The petrology requires source areas with granitic rocks, andesite, basalt, and chert exposed. Possible source areas include the Crescent Formation, the Coast Plutonic Complex, the San Juan Islands, Vancouver Island, and the North Cascades. Deposition of the Quimper Sandstone and Marrowstone Shale marks the culmination of movement on the Discovery Bay Fault Zone. These sediments are found overlying the fault zone but not apparently offset by it. Bedding attitudes are consistent across the fault zone. The Discovery Bay Fault Zone has been suggested to be a tectonic suture between the Crescent Terrane and local Tertiary North America. The arrival and subsequent docking of the Crescent Terrane is coincident with a plate reorganization along with a decrease in convergence rates between the Farallon and North American plates. Cessation of movement on the Discovery Bay Fault, along with simple thermal subsidence of the Crescent basalts, deepened the basin, as shown by the sediments grading from i hummocky cross-stratified sands of the inner shelf to silty shales of the outer shelf. ii ACKNOWLEDGMENTS I would like to thank my thesis committee members: Dr. Christopher A. Suczek who gave hours of guidance and for continuous encouragement especially during the final days of this project; Dr. David C. Engebretson for many stimulating discussions, particularly on tectonics and for introducing me to the problem; and Dr. Randall S. Babcock for petrographic consultation. I would also like to thank Patty Combs and Vicki Critchlow for their patience in answering many questions regarding graduate student life. Thanks to George Mustoe for consultation on photography and thin section production. Special thanks to Dr. Joanne Bourgeois and Elana Leithold for discussions on sedimentology. Dr. Mark Brandon for discussions about coeval sedimentary rocks on Vancouver Island, and Dr. Robert Gray, Mr. Karl Halbach, Mr. Philip Olson, and Ms Terri Plake of Santa Barbara City College for introducing me to the great science of geology. I would also like to thank Cmdr. J.A. Hamilton of the United States Navy and all personnel at NUWES, Indian Island Detachment, for allowing me access to the base. Thanks also go to the numerous residents of Marrowstone Island and the Quimper Peninsula who allowed me access to the rocks on their property. Many thanks to the members of the 'Olympic Team': Kurt Anderson for introducing me to the Olympic Peninsula field experience at its wettest, Jennie DeChant for field assistance, Ron Moyer for discussions on tectonics, Joel Purdy and Tim Roberts for many Olympic discussions and for putting up with me as a house-mate. Special thanks to Kurt Anderson, Keith Pine, and Moira Smith whose commitment to recreation in the form of aerobics, skiing, sail boarding. Ff- and mountaineering allowed me to experience the specialness of the Pacific Northwest which not only stimulated the body but also the mind, allowing this project to be completed. Most of al 1 I would like to thank my parents. Bill and Selma Rauch, for their continual love and support, and who taught me at an early age the value of education. This project was partial ly funded by the American Association of Petroleum Geologists, Grants-in-Aid program, and a grant from the Geology Department at Western Washington University. iv TABLE OF CONTENTS Abstract i Aknowledgements iii Table of Contents v List of Figures vii List of Tables and Plates x Introduction 1 Regional Geology 1 Local Geology 7 Previous Work Depositional Environment 14 Introduction 14 Depositional Features 14 Hummocky Cross-Stratified Facies 14 Laminated Facies 22 Silty Shale Facies 22 Interpretation 28 Discussion 33 Petrology and Petrography 36 Introduction 36 Descriptive Petrography 39 Post-Depositional Changes 47 Provenance 51 Tectonic Provenance 51 Possible Source Areas 53 Coast Plutonic Complex 55 San Juan Islands 55 V Vancouver Island 56 North Cascades 57 Olympic Peninsula 58 Discussion 59 Deposition and Tectonics 61 Deposition 61 Discussion of Tectonics 66 Summary and Conclusions 71 References Cited 73 Appendix 1: Description and Discussion of Grain Categories 79 Appendix 2: Modal Analysis of Samples from the Hummocky Cross- Stratified Facies 90 Appendix 3: Modal Analysis of Samples from the Laminated Facies 93 Appendix 4: Modal Analysis of Samples from the Silty Shale Facies 99 Appendix 5; Average Modal Compositions 100 vi LIST OF FIGURES Figure 1. Generalized location map showing the distribution of the Olympic Core Terrane and the Crescent Terrane. 2 Figure 2. Generalized cross-section of the Olympic Peninsula from west to east. 4 Figure 3. Map showing major faults. 6 Figure 4. Geologic Map of the Quimper Peninsula area showing the location of the Quimper Sandstone and Marrowstone Shale. 8 Figure 5. Composite stratigraphic column of the Quimper Peninsula area. 10 Figure 6. Stratigraphic column of Marrowstone Island. 16 Figure 7. Stratigraphic column of Indian Island. 18 Figure 8. Dynamic zones of the beach to outer shelf. 19 Figure 9. Hummocky cross-strata. 21 Figure 10. Concretionary pebble lens. 21 Figure 11.