1. Isotopic Composition of the Ogallala-high Plains Aquifer Andvadose Zone
- Author
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Britney S. Katz, Randy L. Stotler, Donald O. Whittemore, Adam Yoerg, Greg A. Ludvigson, Daniel R. Hirmas, Jon J. Smith, and James J. Butler
- Subjects
Hydrology ,geography ,geography.geographical_feature_category ,Artesian aquifer ,Specific storage ,Earth and Planetary Sciences(all) ,Aquifer ,General Medicine ,Groundwater recharge ,vadose zone ,recharge ,Ogallala-High Plains aquifer ,Aquifer test ,Phreatic zone ,Depression-focused recharge ,Groundwater model ,stable isootpes ,equilibrium method ,Geology - Abstract
The Ogallala-High Plains aquifer is an important resource for irrigated agriculture in a semi-arid region of the United States. Steep declines in groundwater levels are putting increasing strain on the viability of the aquifer for irrigation, necessitating improved estimates of recharge rates and sources to the aquifer. This study uses a combined approach to obtain high resolution geochemical and isotopic composition of the vadose zone and aquifer pore fluids to better understand recharge dynamics to the aquifer. Significant differences between the shallow, intermediate and deep vadose zone and shallow and deep aquifer indicate modern precipitation is not providing a significant source of recharge to the aquifer across a large area (diffuse recharge). Rather, recharge to the aquifer is a result of either focused recharge or long-term, delayed drainage from the portion of the vadose zone which was saturated before irrigation development.
- Published
- 2015