Salinization of the Upper Colorado River— Fingerprinting Geologic Salt Sources Scientific Investigations Report 2009–5072 U.S. Department of the Interior U.S. Geological Survey COVER: Uncompahgre River near Ridgway, Colorado. Photograph by John G. Elliott, U.S. Geological Survey, July 20, 2005. Salinization of the Upper Colorado River— Fingerprinting Geologic Salt Sources By Michele L. Tuttle and Richard I. Grauch Scientific Investigations Report 2009–5072 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Suzette M. Kimball, Acting Director U.S. Geological Survey, Reston, Virginia: 2009 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Suggested citation: Tuttle, M.L., and Grauch, R.I., 2009, Salinization of the upper Colorado River—Fingerprinting geologic salt sources: U.S. Geological Survey Scientific Investigations Report 2009–5072, 62 p. iii Contents Abstract ...........................................................................................................................................................1 Introduction.....................................................................................................................................................1 Methods...........................................................................................................................................................2 Sample Collection .................................................................................................................................2 Analytical Procedures..........................................................................................................................2 Results .............................................................................................................................................................4 Flow and Solute Loads .........................................................................................................................4 Piper Diagrams ......................................................................................................................................5 Geochemistry at Stations Along Tributary Watersheds to the Upper Colorado River Above Cisco, Utah ............................................................................................................................6 Eagle River .............................................................................................................................................7 Eagle River Near Minturn, Colorado .........................................................................................7 Eagle River at Avon, Colorado ...................................................................................................8 Eagle River at Gypsum, Colorado ..............................................................................................8 Geochemical Evolution Along the Eagle River ........................................................................8 Roaring Fork River at Glenwood Springs, Colorado ........................................................................9 Gunnison River ....................................................................................................................................10 Uncompahgre River ............................................................................................................................10 Uncompahgre River Near Ouray, Colorado ...........................................................................10 Uncompahgre River Near Ridgway, Colorado ......................................................................10 Uncompahgre River at Delta, Colorado .................................................................................10 Geochemical Evolution Along the Uncompahgre River ......................................................12 Gunnison River Below Gunnison Tunnel, Colorado.......................................................................13 North Fork of the Gunnison River Below Paonia, Colorado .........................................................13 Lower Gunnison River ........................................................................................................................13 Gunnison River at Delta, Colorado ..........................................................................................13 Gunnison River Near Grand Junction, Colorado ..................................................................14 Geochemical Evolution Along the Gunnison River ........................................................................14 Dolores and San Miguel Rivers ........................................................................................................16 San Miguel River at Uravan, Colorado ...................................................................................16 Dolores River at Dolores, Colorado ........................................................................................16 Dolores River at Bedrock, Colorado .......................................................................................16 Dolores River Near Cisco, Utah ...............................................................................................17 Geochemical Evolution Along the Dolores River ..................................................................18 Geochemistry in Main Stem Colorado River Above Cisco, Utah .........................................................19 Colorado River Near Kremmling, Colorado ....................................................................................19 Colorado River Above Glenwood Springs, Colorado ....................................................................19 Colorado River Near Cameo, Colorado ...........................................................................................20 Plateau Creek Near Cameo, Colorado ............................................................................................21 Colorado River Near Colorado-Utah State Line .............................................................................21 Colorado River Near Cisco, Utah .....................................................................................................21 Geochemical Evolution of the Colorado River Above Cisco ........................................................22 iv Fingerprinting Major Geologic Salt Sources ...........................................................................................23 Evaporites in the Eagle Valley Evaporite .........................................................................................24 Evaporites in the Paradox Formation ..............................................................................................24 Salts Derived From Weathering of the Mancos Shale .................................................................25 Dolores River Watershed .........................................................................................................25 Gunnison River Watershed ......................................................................................................25 Colorado River Headwater-Plateau Watershed ...................................................................26 Summary........................................................................................................................................................26 Acknowledgments ......................................................................................................................................26 References Cited..........................................................................................................................................27 Appendix I. Chemical and Isotopic Data for All Water Samples Collected in This Study ............30 Appendix II. Chemical Loads for Major Chemical Elements and Total Solutes .............................50 Appendix III. Chemical, Isotopic, and Mineralogical Data for All Geologic Samples Collected in This Study ..................................................................................................................53 Figures 1. Map showing study area and sampling locations ..................................................................3 2. Schematic of flow during high-water, irrigation, and base flows ........................................4 3. Schematic of total solute loads during high-water, irrigation, and base flows .................5 4. Piper plots for water during high-water flow, irrigation flow, and base flow .....................6 5. Index map for watersheds considered in this study ...............................................................7 6. Map of the Eagle River watershed ............................................................................................7