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Trace Element Analysis of Selected Springs in the Virgin River Basin

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Trace Element Analysis of Selected Springs in the Virgin River Basin UNLV Theses, Dissertations, Professional Papers, and Capstones 5-1996 Trace element analysis of selected springs in the Virgin River Basin Mary A. Yelken University of Nevada, Las Vegas Follow this and additional works at: https://digitalscholarship.unlv.edu/thesesdissertations Part of the Fresh Water Studies Commons, Geology Commons, and the Hydrology Commons Repository Citation Yelken, Mary A., "Trace element analysis of selected springs in the Virgin River Basin" (1996). UNLV Theses, Dissertations, Professional Papers, and Capstones. 1458. http://dx.doi.org/10.34917/3445028 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 Theses, Dissertations, Professional Papers, and Capstones by an authorized administrator of Digital Scholarship@UNLV. For more information, please contact [email protected]. TRACE ELEMENT ANALYSIS OF SELECTED SPRINGS IN THE VIRGIN RIVER BASIN by Mary A Yelken A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Water Resoorces Management Department of Geoscience University ofNevada, Las Vegas May 1996 1l1c thesis of Mary A. Yelken for the degree of Master of Science in Water Resources Management is approved. Graduate Faculty Representative, Vernon F. Hodge, Ph.D. Dean ofth~ Graduate College, Dr. Ronald W. Smith, Ph.D. University ofNevada, Las Vegas May 1996 ii ABSTRACT Spring water from 23 springs in and near the Virgin River Basin (southwestern Utah, northwestern Arizona, and southeastern Nevada) was collected and analyzed for field parameters and chemical concentrations. Trace element concentrations and major ion chemistry were used to determine the potential for using water chemistry, specifically trace element concentrations, to provide information on spring water source and flow pathways. Principal Component Analysis (PCA), rare earth element (REE) normalization patterns, and mineral equihorium modeling (PHREEQE) techniques were used to analyze the data set. The PCA analysis grouped spring water with similar chemistries. Four major spring water groups were displayed from the analysis of the chemical data set. Pah Tempe Hot Springs grouped away from other springs except when the PCA analysis included only REE data. Petrified, Blue Point, and Roger's springs formed a consistent group throughout the PCA Clover-UNK, Creeper, and Putting Green springs formed an isolated group only when REE data was a part of the PCA The remainder of the springs clustered together with few subgroups emerging when different combinations of the data -· ·; set were entered into the PCA The analyses suggest that spring water chemical concentrations are a result of interactions with the rocks through which the waters flow. The small number of sampling locations relative to the large areal extent of the Virgin River Basin limited the usefulness of the water chemistry to suggest actual spring source iii and flow pathways. Although the PCA displayed four major spring water groupings, additional research is warranted in the study area to gain a better understanding of the groundwater flow system. iv TABLE OF CONTENTS ABSTRACT............................................................................................................. iii LIST OF FIGURES.................................................................................................. vn LIST OF TABLES................................................................................................... viii LIST OF ABBREVIATIONS................................................................................... ix ACKNOWLEDGMENTS........................................................................................ X CHAPTER I INTRODUCTION............................................................................... 1 Review of Literature................................................................... .. .. .. .. .. .. ... 5 Overview ofthe Virgin River Basin............................................................... 8 The Virgin River .............................................·................................... 8 Climate.............................................................................................. 11 History of the Virgin River Basin....................................................... 15 Demands on the Virgin River Basin.................................................... 16 CHAPTER2 GEOLOGY .......................................................................................... 19 Major Geologic Structures............................................................................. 23 Geologic Subdivisions of the Virgin River Basin............................................ 25 Upper Virgin River Basin................................................................... 25 Central Virgin River Basin.................................................................. 25 Lower Virgin River Basin................................................................... 26 CHAPTER 3 GROUNDWATER.............................................................................. 28 Previous Investigations.................................................................................. 28 Major Springs................................................................................................ 31 Pah Tempe Hot Springs..................................................................... 31 Toquerville Springs............................................................................ 34 Littlefield Springs............................................................................... 35 CHAPTER 4 METHODOLOGY.............................................................................. 36 Field Reconnaissance and Spring Selection..................................................... 36 Sample Collection.......................................................................................... 37 Sample Analysis............................................................................................. 42 v CHAPTER 5 RESULTS OF CHEMICAL ANALYSIS............................................. 44 Field Parameters......................................................................................... ... 44 Chemical Concentrations................................................................................ 47 CHAPTER 6 DATA ANALYSIS RESULTS AND DISCUSSION........................... 60 Major Ion Chemistry...................................................................................... 60 Principal Component Analysis........................................................................ 66 Resuhs of Principal Component Analysis............................................ 68 Rare Earth Element Concentrations................................................................ 79 Rare Earth Element Normalization ...................................................... 81 PHREEQE ..................................................................................................... 86 Stable Isotopes (oxygen-IS and deuterium).................................................... 92 Major Spring Water Groups........................................................................... 95 Roger's, Blue Point, and Petrified Springs........................................... 95 Clover Mountain Springs.................................................................... 98 Pah Tempe Hot Springs...................................................................... 99 Majority of Springs in the Study Area................................................. 99 CHAPTER 7 CONCLVSION AND SUGGESTIONS FOR FUTURE RESEARCH......................................................................... 101 APPENDICES ........................................................................................................... 106 Appendix A: Spring Site Geology.................................................................. 107 Appendix B: Spring Site Descriptions............................................................ 111 Appendix C: Field Reconnaissance................................................................ 118 Appendix D: Principal Component Analysis .................................................. 122 Appendix E: Rare Earth Element Normalization............................................ 143 REFERENCES.......................................................................................................... 147 vi LIST OF FIGURES Figure 1: General Location of Study Area............................................................... 2 Figure 2: Map of Study Area.................................................................................. 9 Figure 3: Location Map for Climatic Data Stations.................................................. 13 Figure 4: Geologic Diagram of Colorado Plateau and Basin and Range................... 20 Figure 5: Generalized Stratigraphy from the Lower Virgin River Basin................... 21 Figure 6: Generalized Stratigraphy of the Upper Virgin River Basin........................ 22 Figure 7: Spring Location
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