Cooperative Agreement for Affiliated Partner with Great Basin Cooperative Ecosystems Studies Unit

The USGS is offering a funding opportunity to a CESU partner for research on applications of isotope geochemistry to surface and groundwater hydrologic problems.  Essential components of the funding opportunity are: 1) student, faculty, and laboratory support for application, refinement, and development of geochemical methods, that 2) address sediment and water sources and transport pathways, through 3) application of a wide range of stable and radio-isotopic systems (ranging from hydrogen, helium, and lithium through uranium and lead), by 4) analysis of the isotopic composition of diverse sample media (including plant and animal tissue, sediment, rock, and aqueous phases, especially high salinity brine). There is an urgent need for isotopic characterization of sediment from the San Juan River Basin.  The objective of this research is to characterize fine grained sediment with respect to different sources within the basin.  An established approach is to use lead (Pb) isotopic analysis to differentiate sediment sources.  Would extend the application of this research to new sample material from Lake Powell, including sediment traps in the San Juan delta, cores throughout the San Juan and Colorado River deltas, and suspended sediment samples from the USGS stream gage at Mexican Hat, Utah.  Comprehensive geochemical analysis for many samples exists, and in many cases have splits of previously analyzed powders.  Keys tasks would be to:  1) evaluate all sediment chemistry data, 2) choose samples from the sample library for Pb isotope analysis, 3) manage sample submission to laboratory, 4) manage data delivery from the lab, 5) work with USGS Utah Water Science Center staff to establish QA/QC procedures for the data, 6) explore the use of additional isotopic systems (e.g., 87Sr/86Sr) to address provenance questions.