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Denali National Park and Preserve Geologic Resources Inventory Report

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Denali National Park and Preserve Geologic Resources Inventory Report National Park Service U.S. Department of the Interior Natural Resource Program Center Denali National Park and Preserve Geologic Resources Inventory Report Natural Resource Report NPS/NRPC/GRD/NRR—2010/244 THIS PAGE: Mountaineering rangers on backcountry patrol in a land of giants. Ruth Glacier, Denali National Park and Preserve. National Park Service photograph by Tucker Chenoweth, Denali National Park and Preserve. ON THE COVER: View of the terminus of Buckskin Glacier with Mount McKinley (20,320 ft) in the back- ground, Denali National Park and Preserve, Alaska, August 6, 2004. Photo courtesy of Ronald D. Karpilo, Jr., Colorado State University. Denali National Park and Preserve Geologic Resources Inventory Report Natural Resource Report NPS/NRPC/GRD/NRR—2010/244 Geologic Resources Division Natural Resource Program Center P.O. Box 25287 Denver, Colorado 80225 September 2010 U.S. Department of the Interior National Park Service Natural Resource Program Center Ft. Collins, Colorado The National Park Service, Natural Resource Program Center publishes a range of reports that address natural resource topics of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Report Series is used to disseminate high-priority, current natural resource management information with managerial application. The series targets a general, diverse audience, and may contain NPS policy considerations or address sensitive issues of management applicability. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner. This report received informal peer review by subject-matter experts who were not directly involved in the collection, analysis, or reporting of the data. Views, statements, findings, conclusions, recommendations, and data in this report do not necessarily reflect views and policies of the National Park Service, U.S. Department of the Interior. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the U. S. Government. Printed copies of this report are produced in a limited quantity and they are only available as long as the supply lasts. This report is available from the Geologic Resources Inventory website (http://www.nature.nps.gov/geology/inventory/gre_publications.cfm) and the Natural Resource Publications Management website (http://www.nature.nps.gov/publications/ NRPM). Please cite this publication as: Thornberry-Ehrlich, T. 2010. Denali National Park and Preserve: geologic resources inventory report. Natural Resource Report NPS/NRPC/GRD/NRR—2010/244. National Park Service, Ft. Collins, Colorado. NPS 184/105592, September 2010 ii NPS Geologic Resources Division Contents Lists of Figures and Tables ........................................................................................... iv Executive Summary ....................................................................................................... v Acknowledgements ...................................................................................................... vi Introduction ................................................................................................................... 1 Purpose of the Geologic Resources Inventory ............................................................................................................... 1 Park Setting and Establishment .................................................................................................................................... 1 Geologic Setting .......................................................................................................................................................... 1 Geologic Issues .............................................................................................................. 5 Introduction ................................................................................................................................................................. 5 Glacial Issues................................................................................................................................................................ 5 Earthquakes and Earthquake Hazards ........................................................................................................................... 6 Mining and Disturbed Lands......................................................................................................................................... 8 Permafrost Issues ......................................................................................................................................................... 9 Surface Water Issues .................................................................................................................................................. 10 Paleontological Resources .......................................................................................................................................... 11 Geothermal Activity ................................................................................................................................................... 12 Slope Processes and Erosion ....................................................................................................................................... 12 General Geology Issues and Research Possibilities ....................................................................................................... 13 Geologic Features and Processes ................................................................................ 20 Mt. McKinley (Denali) ................................................................................................................................................. 20 Denali Fault System .................................................................................................................................................... 20 Kantishna Hills ........................................................................................................................................................... 21 Accreted Terranes ...................................................................................................................................................... 22 Glacial Features .......................................................................................................................................................... 22 Glaciers ..................................................................................................................................................................... 24 Glacial Retreat and Surging Glaciers ........................................................................................................................... 25 Other Notable Geologic Features ................................................................................................................................ 25 Map Unit Properties .................................................................................................... 31 Geologic Units of Denali National Park and Preserve ................................................................................................... 32 Geologic History .......................................................................................................... 51 Precambrian (prior to 542 million years ago) ............................................................................................................... 51 Paleozoic Era (542 to 251 million years ago) ............................................................................................................... 51 Mesozoic Era (251 to 65.5 million years ago) .............................................................................................................. 51 Cenozoic Era (the past 65.5 million years) ................................................................................................................... 52 Glossary ........................................................................................................................ 58 Literature Cited ............................................................................................................ 64 Appendix A: Overview of Digital Geologic Data ....................................................... 69 Appendix B: Scoping Session Participants ................................................................. 73 Attachment 1: Geologic Resources Inventory Products CD DENA Geologic Resources Inventory Report iii List of Figures Figure 1: Map of Alaska Showing major mountain ranges and rivers. ............................................................................... 2 Figure 2: Generalized cross section through central Alaska showing the juxtaposition of accreted terranes ....................... 3 Figure 3: Map of Denali National Park and Preserve.......................................................................................................... 4 Figure 4: The Straightaway Glacier is one of many surge-type glaciers which issue from Mt McKinley. ............................ 14 Figure 5: Glacial retreat photography pairing at the head
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