UNLV Retrospective Theses & Dissertations 1-1-2006 Volcanology and petrogenesis of the Navajo Lake volcanic field Shara L Stowell University of Nevada, Las Vegas Follow this and additional works at: https://digitalscholarship.unlv.edu/rtds Repository Citation Stowell, Shara L, "Volcanology and petrogenesis of the Navajo Lake volcanic field" (2006). UNLV Retrospective Theses & Dissertations. 1980. http://dx.doi.org/10.25669/6mt8-tvhq This Thesis is protected by copyright and/or related rights. It has been brought to you by Digital Scholarship@UNLV with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in UNLV Retrospective Theses & Dissertations by an authorized administrator of Digital Scholarship@UNLV. For more information, please contact [email protected]. VOLCANOLOGY AND PETROGENESIS OF THE NAVAJO LAKE VOLCANIC FIELD by Shara L. Stowell Bachelor o f Science University o f Idaho, Moscow 2001 A thesis submitted in partial fulfillm ent o f the requirements for the Master of Science Degree in Geology Department of Geoscience College of Sciences Graduate College University of Nevada, Las Vegas May 2006 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 1436793 Copyright 2006 by Stowell, Shara L. All rights reserved. INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. UMI UMI Microform 1436793 Copyright 2006 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Thesis Approval The Graduate College University of Nevada, Las Vegas December 14 _,2005_ The Thesis prepared by Shara L. Stowell E ntitled VOLCANOLOGY AND PETROGENEIS OF THE NAVAJO LAKE VOLCANIC FIELD is approved in partial fulfillment of the requirements for the degree of Master of Science Examination Committee Chair s : Dean of the Graduate College Examination Committee Member C [<3uc^ C rD Ld Examination Committee Member Graduate College Faculty Representative 11 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ABSTRACT Volcanology and Petrology o f the Navajo Lake Volcanic Field by Shara Stowell Dr. Eugene I. Smith, Examination Committee Chair Professor o f Geology University o f Nevada, Las Vegas The Navajo Lake voleanic field is an ideal natural laboratory for volcanologieal and geoehemical studies. This field extends from Navajo Lake, east o f Cedar City, Utah to Panguiteh Lake, Utah and lies in the Colorado Plateau and Basin and Range Transition Zone between the Hurrieane and Sevier faults. The voleanie field is eharacterized by numerous basalt flows that erupted from more than 28 cinder eones. Many o f the cones are aligned in a SE-NW direction. Three stages o f basalt flows are reeognized by mineralogy and morphology. Additionally, traehy-andesite oeeurs in the Panguiteh Lake area. Many o f the flows appear to be young beeause they are devoid o f vegetation and have flow fronts 10 to 100 meters high. Flows erupted from the base and on the flanks of several einder eones that are generally well covered by vegetation. In the Panguiteh Lake area, the northernmost A ’a flow is composed o f a basal basalt flow and an upper traehy- andesite flow. These flows appear to have erupted from a eommon fissure system. The lava flow just north o f Navajo Lake covers approximately 4 km^ and erupted from two vents on the west flank o f a well-vegetated eone. Tertiary Brian Head and Claron formations and Isom formation pyroclastic flows underlie the volcanic field. I ll Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ABSTRACT .................................................................................................................................. i i i LIST OF FIGURES...................................................................................................................... v ACKNOWLEDGMENTS.........................................................................................................v ii CHAPTER 1 INTRODUCTION ........................................................................................... 1 Regional Geology and Background ..................................................................................... 2 Previous W ork ........................................................................................................................ 3 CHAPTER 2 VOLCANIC STRATIGRAPHY AND GEOCHRONOLOGY................ 8 CHAPTER 3 MINERALOGY AND PETROGRAPHY..................................................20 CHAPTER 4 GEOCHEMISTRY AND GEOCHRONOLOGY.................................... 23 Analytical Techniques for Geoehemistry .......................................................................... 23 Geochemistry o f M afic Rocks ............................................................................................. 24 Analytical Techniques for Geochronology ........................................................................ 26 CHAPTER 5 PETROGENESIS .......................................................................................... 36 Model Descriptions ................................................................................................................36 Fractional Crystallization ........................................................................................... 36 Assimilation .................................................................................................................37 Independent Partial M elts ..........................................................................................40 Chemical Variation within Individual Volcanic Centers ...................................... 41 The Mantle Boundary ........................................................................................................... 51 CHAPTER 6 SUMMARY AND CONCLUSIONS..........................................................55 A P P E N D IC E S .............................................................................................................................56 XRF & ICP-MS data............................................................................................................. 57 Isotope data .............................................................................................................................73 Sample Location ....................................................................................................................74 Step Heating data ...................................................................................................................76 REFERENCES ............................................................................................................................82 VITA .............................................................................................................................................87 IV Reproduced with permission of the copyright owner. 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LIST OF FIGURES Figure I Map of Utah .............................................................................................................. 6 Figure 2 Satellite photo of Navajo Lake Voleanie Field ................................................... 7 Figure 3 General stratigraphy .............................................................................................. 12 Figure 4 Cinder pit layering from Haneock Peak ............................................................... 13 Figure 5 Cinder pit layering within the N LVF ....................................................................14 Figure 6 Navajo Lake Cinder cone vegetation ................................................................... 15 Figure 7 Boeas on Navajo Lake Cinder Cone ..................................................................... 16 Figure 8 Aerial photo o f Panguiteh North flows and fissures ............................................ 17 Figure 9 M iller Knoll vents .....................................................................................................18 Figure 10 Arcuate Andésite fissure ........................................................................................19 Figure 11 Classifieation diagram ..........................................................................................25 Figure 12 Alkaline-Subalkaline classification diagram ....................................................