Equus Beds Aquifer

The Equus Beds Aquifer is a distinct part the High Plains Aquifer System{{cite web |access-date = 2023-04-07 |quote= The Equus Beds aquifer is part of a regional aquifer system known as the High Plains aquifer system. |url= http://www.gmd2.org/About%20us.html |title= ABOUT GMD2 |website= Equus Beds Groundwater Management District No. 2 }} and is a principal municipal aquifer in south-central Kansas,{{cite journal |title= Water Resources of Sedgwick County, Kansas |first= Hugh E. |last= Bevans |publisher= United States Geological Survey |journal= Water-Resources Investigations |issue= Report 88-422 |url= https://pubs.usgs.gov/wri/1988/4225/report.pdf |page= 4 |access-date = 2023-04-07 |year= 1989 |quote= Results of an investigation of the geology and ground-water resources of the Equus beds, the principal aquifer in the area, ... }} underlying Hutchinson, McPherson, Newton, and Wichita.{{cite journal |url= https://www.kgs.ku.edu/Hydro/Equus/OFR00_60/index.htm |journal= KGS Geohydrology Reports |issue= Open File Report 2000-60 (Version 2.0) |publisher= Kansas Geological Survey |title= Sources, Transport, and Management of Salt Contamination in the Groundwater of South-Central Kansas |author= Hillel Rubin, David Young, and Robert Buddemeier |date= 2001 |access-date = 2023-04-07 |series= Equus Beds Mineral Intrusion Project}}{{cite web |title = Boundaries of Equus Beds Location |website= Public Works & Utilities |url= https://www.wichita.gov/PWU/UtilitiesDocuments/EQUUS%20BEDS%20LOCATION.pdf |publisher= City of Wichita |access-date = 2023-04-07 }}

While generally illustrated as an extension of the Miocene-Pliocene Ogallala Aquifer, this aquifer is composed of alternating beds of sand and clay mostly deposited in the later Pleistocene and was named the "McPherson Equus Beds" for having characteristic modern horse fossils.{{cite web | title = Geologic Unit: McPherson | series = Geolex — Significant Publications | work = National Geologic Database | publisher = United States Geological Survey | url = https://ngmdb.usgs.gov/Geolex/UnitRefs/McPhersonRefs_8782.html | access-date = 2023-04-07 }}{{cite web | title = Geologic Unit: Equus | series = Geolex — Significant Publications | work = National Geologic Database | publisher = United States Geological Survey | url = https://ngmdb.usgs.gov/Geolex/UnitRefs/EquusRefs_16578.html |access-date = 2023-04-07 |quote= The USGS in general calls the beds containing EQUUS remains the EQUUS zone, ... }}

The aquifer beds overlie, and are partially recharged by the Dakota Aquifer and certain Permian aquifers. These particular High Plains Aquifers are also known sources of widespread natural salt contamination, including portions of the Equus Beds, which can be aggravated by human extraction of water as well as by salt mining and oil wells.{{cite journal |url= https://www.kgs.ku.edu/Hydro/Publications/2004/OFR04_62/ |journal= KGS Geohydrology Reports |issue= Open-file Report 2004-62 |publisher= Kansas Geological Survey |title= Geochemical Identification of Sources of Salinity in Ground Waters of the High Plains Aquifer South of McPherson, Kansas |first= Donald O. |last= Whittemore |access-date = 2023-04-07}}{{cite journal |journal= KGS Geohydrology Reports |issue= Open File Report 2000-30 |publisher= Kansas Geological Survey |title= Final Summary and Data Report: The Equus Beds Mineral Intrusion Project |author= D. P. Young, R. W. Buddemeier, D. O. Whittemore, and H. Rubin |url= https://www.kgs.ku.edu/Hydro/Equus/OFR00_30/ |date= 2001 |access-date = 2023-04-07 }}