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New Methods for Sourcing Fine-Grained Volcanic Artifacts in the Salish Sea: a Holistic Approach

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New Methods for Sourcing Fine-Grained Volcanic Artifacts in the Salish Sea: a Holistic Approach Western Washington University Western CEDAR WWU Graduate School Collection WWU Graduate and Undergraduate Scholarship 2014 New methods for sourcing fine-grained volcanic artifacts in the Salish Sea: a holistic approach Whitney S. (Whitney Selina) Osiensky Western Washington University Follow this and additional works at: https://cedar.wwu.edu/wwuet Part of the Anthropology Commons Recommended Citation Osiensky, Whitney S. (Whitney Selina), "New methods for sourcing fine-grained volcanic artifacts in the Salish Sea: a holistic approach" (2014). WWU Graduate School Collection. 341. https://cedar.wwu.edu/wwuet/341 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]. NEW METHODS FOR SOURCING FINE-GRAINED VOLCANIC ARTIFACTS IN THE SALISH SEA: A HOLISTIC APPROACH By Whitney Selina Osiensky Accepted in Partial Completion Of the Requirements for the Degree Master of Arts Kathleen L. Kitto, Dean of the Graduate School ADVISORY COMMITTEE Chair, Dr. Sarah K. Campbell Dr. Todd A. Koetje Dr. Joan Stevenson 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 right to 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. Whitney S. Osiensky May 9, 2014 NEW METHODS FOR SOURCING FINE-GRAINED VOLCANIC ARTIFACTS IN THE SALISH SEA: A HOLISTIC APPROACH A Thesis Presented to The Faculty of Western Washington University In Partial Fulfillment Of the Requirements for the Degree Master of Arts by Whitney Selina Osiensky May 2014 Abstract This investigation presents an alternative method to sourcing fine-grained volcanic (FGV) artifacts from the Salish Sea in western Washington. Past sourcing strategies have utilized geochemical methods focusing on the trace element composition of artifacts. This research has verified the extensive use of the only known geologic source (Watts Point, B.C.) but has not yet identified other geologic sources for artifacts from the Salish Sea. The research presented herein develops a three-tiered holistic approach to sourcing FGV artifacts from the region. The addition of whole rock major element and mineralogical analyses in conjunction with trace element analysis develops a more accurate method to sourcing FGV artifacts. Artifacts from nine sites in western Washington (45WH1, 45WH4, 45WH17, 45WH34, 45WH55, 45SK46, 45WH300, and three sites from the North Cascades National Park) are compared with geologic samples from nine locations in the North Cascades and Salish Sea using this three-tiered holistic approach to sourcing. Using this methodology, 17 new unknown sources are identified; these sources represent many types of FGVs (dacite, andesite, rhyolite, and trachydacite). Of the artifacts, 72% are composed of dacite while the remaining 28% are other various types of FGVs. Of the dacite artifacts only about half come from Watts Point, showing that native people were not dependent on Watts Point as a source for their tool stone and had access to many other FGV sources. iv Acknowledgements First, I would like to thank my thesis committee Dr. Sarah Campbell, Dr. Todd Koetje and Dr. Joan Stevenson for your tireless work helping me complete my Master’s degree. Your knowledge, insight, support and encouragement has had a profound influence on my life. Thank you! Thank you to George Mustoe at Western Washington University for the hours you spent helping me understand the geology behind the artifact. Your knowledge on the scanning electron microscope, mineralogy and sample preparation was crucial to the methodology presented herein. Erin Macri at Scientific Technical Services at WWU was essential to teaching me how to use the scanning electronic microscope. Your knowledge on the use of the microscope as well as how to properly prepare samples was vital to my thesis. Thank you! Thank you to Dr. Craig Skinner at Northwest Research Obsidian Studies Laboratory for analyzing my artifacts and geologic samples and for answering many question regarding the results. The results you provided were crucial to the results of this thesis. I also want to thank the Western Washington University’s Graduate Research Fund who provided the funding for this analysis. Geologists Susan Debari (WWU) and Dave Tucker were very helpful in understanding the geology of Mount Baker. Thank you for the time you spent with me showing me samples of volcanic rock in the region and for taking me with you to Nooksack Falls to obtain dacite samples. I would also like to thank geologist Tom Sisson (USGS) for helping me understand the geology of Glacier Peak and geologist Joe Dragovich (DNR) for providing me with information on lahar deposits from Glacier Peak. Thank you to Kim Kwarsick, Dave Tucker, Sarah Campbell and Julie Gross who provided me with geologic samples that were used in this thesis. Thank you also to Dr. John Greenough (UBC) for answering many questions regarding his research on mineralogical sourcing of artifacts. I would also like to acknowledge the incredible support that my fellow graduate students gave me during this process. Your expertise and encouragement was vital to the completion of this thesis. Lastly, thank you to my family who were so supportive in this endeavor. Thank you to my parents for your support throughout this process. Thank you to my father-in-law for your editing, advice and encouragement. Thank you, especially, to my husband who spent many hours with me canvasing the region looking for the geologic samples that were used in this thesis. Your support and encouragement throughout this project mean everything to me. I can’t thank you enough. Lastly, I want to thank my children who are my reason for everything I do in my life. This is dedicated to you. v Table of Contents Abstract………………………………………………………………………………………………………….………………iv Acknowledgments…………………………………………………………………....…………………..….…………….v List of Tables……………………………………………………………………………………………….….…………….viii List of Figures………………………………………………………………………………………………….……………….x Chapter I: Introduction………………………………….……………………………………………….………….…….1 Chapter II: Background on Lithic Procurement in the Northwest Coast…………….………...….5 Past Research on Fine-Grained Volcanic Artifacts in the Salish Sea……….……..………..7 Complications Identified in Past Research………………………………………..…………………..10 Coast Salish Prehistory: Settlement Patterns, Mobility, and Lithic Procurement…….12 Chapter III: Regional Geology and Potential Geologic Sources of Fine Grained Volcanic Artifacts in the North Cascades…….……………………………………………………………….22 Regional Geology……………………………………………………………………………………………….…22 North Cascadian Volcanoes.……………………………………………………………………………….…24 Chapter IV: Methods…………………………………………………………………………………………………..…30 Introduction to Artifact Sourcing…………………………………………..……………………………..30 Archaeological Site and Artifact Sample Selection………………………………………………..31 Geologic Sample Selection……………………………………………..…………………………………….61 Analytical Methods for Sourcing FGV Rocks.………………..…………………………………….…67 Laboratory Methods and Protocols…………………………………………………………………….…76 Chapter V: Results and Discussion…………………………………….….……………………………………....85 Results of Whole Rock Major Element Analysis………………………………………………….….85 Results of Trace Element Analysis..……………………………………………………………………....98 vi Results of Mineralogical Analysis……..………………………………………………………………...102 Discussion……………………………….……….………………………………………………………….……..122 Geographic and Temporal Patterns in Tool Stone Procurement..………………………..126 Chapter VI: Conclusions and Implications…………………………….………………………………………140 Implications for Watts Point……………….………………………………………………………………140 Implications for Mount Baker and Glacier Peak…………….…………………………………….142 Implications for Unknown FGV Sources………………………….……………………………..……143 Value of a Mineralogical Approach to Sourcing FGV Artifacts…………….……………….144 Value of Whole Rock Major Element Analysis …………………..…….…………………………145 References…………………………………………………………………………………………………..……………...147 Appendix A: Sample Catalog…………………………………………………………………………..……………158 Appendix B: SEM Images of All Samples..…………………………………………………………………….173 Appendix C: Results of Trace Element Sourcing..………………………………………………………….311 Appendix D: Mineral Catalog.………..…………………………………………………………………………….317 vii List of Tables Table 2.1 Diagnostic artifacts of Gulf of Georgia culture phases....…………….…………….…..…17 Table 3.1 Lava types and the igneous rocks they produce……………………………………….…..….23
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