National Park Service U.S. Department of the Interior Natural Resource Program Center Zion National Park Geologic Resource Evaluation Report Natural Resource Report NPS/NRPC/GRD/NRR—2006/014 Zion National Park Geologic Resource Evaluation Report Natural Resource Report NPS/NRPC/GRD/NRR—2006/014 Geologic Resources Division Natural Resource Program Center P.O. Box 25287 Denver, Colorado 80225 March 2006 U.S. Department of the Interior Washington, D.C. The Natural Resource Publication series addresses natural resource topics that are of interest and applicability to a broad readership in the National Park Service and to others in the management of natural resources, including the scientific community, the public, and the NPS conservation and environmental constituencies. Manuscripts are peer-reviewed to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and is designed and published in a professional manner. Natural Resource Reports are the designated medium for disseminating 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. Examples of the diverse array of reports published in this series include vital signs monitoring plans; "how to" resource management papers; proceedings of resource management workshops or conferences; annual reports of resource programs or divisions of the Natural Resource Program Center; resource action plans; fact sheets; and regularly-published newsletters. Views and conclusions in this report are those of the authors and do not necessarily reflect policies of the National Park Service. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the National Park Service. Printed copies of reports in these series may be produced in a limited quantity and they are only available as long as the supply lasts. This report is also available from the Geologic Resource Evaluation Program website (http://www2.nature.nps.gov/geology/inventory/gre_publications) on the internet, or by sending a request to the address on the back cover. Please cite this publication as: Graham, J. 2006. Zion National Park Geologic Resource Evaluation Report. Natural Resource Report NPS/NRPC/GRD/NRR—2006/014 . National Park Service, Denver, Colorado. NPS D-259, March 2006 Table of Contents List of Figures .............................................................................................................. iv List of Tables ................................................................................................................ iv Executive Summary ...................................................................................................... 1 Introduction ................................................................................................................... 2 Purpose of the Geologic Resource Evaluation Program ............................................................................................2 General Information and Regional Setting..................................................................................................................2 Park History................................................................................................................................................................2 General Geology ........................................................................................................................................................3 Geologic Issues............................................................................................................. 9 Landslides and Debris Flows......................................................................................................................................9 Earthquakes ...............................................................................................................................................................9 Volcanism.................................................................................................................................................................10 Soil ...........................................................................................................................................................................10 Impacts of Mineral Extraction ...................................................................................................................................10 Quaternary Studies...................................................................................................................................................10 Structural Geology Projects......................................................................................................................................11 Hydrogeology ...........................................................................................................................................................12 Hydrogeology Projects .............................................................................................................................................12 Paleontology and Palynology ...................................................................................................................................12 Diagenesis................................................................................................................................................................13 Identification of Type Sections..................................................................................................................................13 Geologic Features and Processes............................................................................. 17 Map Unit Properties .................................................................................................... 21 Map Unit Properties Table........................................................................................................................................23 Geologic History.......................................................................................................... 27 Tectonic History........................................................................................................................................................27 Depositional History..................................................................................................................................................28 References................................................................................................................... 36 Appendix A: Geologic Map Graphic .......................................................................... 39 Appendix B: Scoping Summary................................................................................. 41 Attachment 1: Geologic Resource Evaluation Products CD ZION Geologic Resource Evaluation Report iii List of Figures Figure 1. Location map of Zion National Park ................................................................................................................4 Figure 2. Location of Zion National Park on the Colorado Plateau ................................................................................5 Figure 3. Geologic cross-section of the Grand Staircase ...............................................................................................6 Figure 4. Sketch map showing major plateaus, terraces, cliff lines, and faults .............................................................7 Figure 5. Stratigraphic column for Zion National Park....................................................................................................8 Figure 6. The distribution of young basalts in southern Nevada and southern Utah ....................................................14 Figure 7. Locations of selected geologic sites in Zion..................................................................................................20 Figure 8. Geologic time scale.......................................................................................................................................33 Figure 9. Depositional environments represented by the strata in Zion National Park.................................................34 Figure 10. Location of the Cretaceous Period, Western Interior Seaway.....................................................................35 List of Tables Table 1. Quaternary research projects identified in the 1999 Workshop......................................................................15 Table 2. Potential research projects identified in the 1999 Workshop at Zion..............................................................16 iv NPS Geologic Resources Division Executive Summary This report has been developed to accompany the digital geologic map produced by Geologic Resource Evaluation staff for Zion National Park. It contains information relevant to resource management and scientific research. The spectacular cliffs, arches, spires, temples, and An abandoned uranium mine and three abandoned oil colorful strata of Zion National Park record changing wells within park boundaries may pose issues in the environmental conditions through 275 million years of future. Both types of operations may impact geologic time. Zion lies in a transition zone where the groundwater