Allan K Clark
Hydrologist, Oklahoma-Texas Water Science Center
Education and Certifications
Master of Science, Geology (2002) University of Texas San Antonio
Bachelor of Science, Geology (1992) University of Texas San Antonio
Associates Degree, General Studies (1987) Victoria College
Affiliations and Memberships*
Professional Geoscientists License (#5877) The State of Texas
Honors and Awards
Bernold M. "Bruno" Hanson DEG Excellence of Presentation Award (2008) AAPG Annual convention
Thirty Years of Service award (2021) USGS
Science and Products
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Geologic framework and hydrogeologic characteristics of the Edwards aquifer, Uvalde County, Texas Geologic framework and hydrogeologic characteristics of the Edwards aquifer, Uvalde County, Texas
The Edwards aquifer in Uvalde County is composed of Lower Cretaceous carbonate (mostly dolomitic limestone) strata of the Devils River Formation in the Devils River trend and of the West Nueces, McKnight, and Salmon Peak Formations in the Maverick basin. Rocks in the Devils River trend are divided at the bottom of the Devils River Formation into the (informal) basal nodular unit...
Authors
Allan K. Clark
Vulnerability of ground water to contamination, Edwards Aquifer recharge zone, Bexar County, Texas, 1998 Vulnerability of ground water to contamination, Edwards Aquifer recharge zone, Bexar County, Texas, 1998
The Edwards aquifer, one of the most productive carbonate-rock aquifers in the Nation, is composed of the Kainer and Person Formations of the Edwards Group plus the overlying Georgetown Formation. Most recharge to the Edwards aquifer results from the percolation of streamflow loss and the infiltration of precipitation through porous parts of the recharge zone. Residential and commercial
Authors
Allan K. Clark
Geologic framework and hydrogeologic characteristics of the Edwards Aquifer outcrop, Medina County, Texas Geologic framework and hydrogeologic characteristics of the Edwards Aquifer outcrop, Medina County, Texas
The hydrogeologic subdivisions of the Edwards aquifer outcrop in Medina County generally are porous and permeable. The most porous and permeable appear to be hydrogeologic subdivision VI, the Kirschberg evaporite member of the Kainer Formation; and hydrogeologic subdivision III, the leached and collapsed members, undivided, of the Person Formation. The most porous and permeable rocks of...
Authors
Ted A. Small, Allan K. Clark
Geologic framework of the Edwards Aquifer and upper confining unit, and hydrogeologic characteristics of the Edwards Aquifer, south-central Uvalde County, Texas Geologic framework of the Edwards Aquifer and upper confining unit, and hydrogeologic characteristics of the Edwards Aquifer, south-central Uvalde County, Texas
The stratigraphic units of the Edwards aquifer in south-central Uvalde County generally are porous and permeable. The stratigraphic units that compose the Edwards aquifer in south-central Uvalde County are the Devils River Formation in the Devils River trend; and the West Nueces, McKnight, and Salmon Peak Formations in the Maverick Basin. The Balcones fault zone is the principal...
Authors
Allan K. Clark, Ted A. Small
Science and Products
Filter Total Items: 15
Filter Total Items: 13
Filter Total Items: 22
Geologic framework and hydrogeologic characteristics of the Edwards aquifer, Uvalde County, Texas Geologic framework and hydrogeologic characteristics of the Edwards aquifer, Uvalde County, Texas
The Edwards aquifer in Uvalde County is composed of Lower Cretaceous carbonate (mostly dolomitic limestone) strata of the Devils River Formation in the Devils River trend and of the West Nueces, McKnight, and Salmon Peak Formations in the Maverick basin. Rocks in the Devils River trend are divided at the bottom of the Devils River Formation into the (informal) basal nodular unit...
Authors
Allan K. Clark
Vulnerability of ground water to contamination, Edwards Aquifer recharge zone, Bexar County, Texas, 1998 Vulnerability of ground water to contamination, Edwards Aquifer recharge zone, Bexar County, Texas, 1998
The Edwards aquifer, one of the most productive carbonate-rock aquifers in the Nation, is composed of the Kainer and Person Formations of the Edwards Group plus the overlying Georgetown Formation. Most recharge to the Edwards aquifer results from the percolation of streamflow loss and the infiltration of precipitation through porous parts of the recharge zone. Residential and commercial
Authors
Allan K. Clark
Geologic framework and hydrogeologic characteristics of the Edwards Aquifer outcrop, Medina County, Texas Geologic framework and hydrogeologic characteristics of the Edwards Aquifer outcrop, Medina County, Texas
The hydrogeologic subdivisions of the Edwards aquifer outcrop in Medina County generally are porous and permeable. The most porous and permeable appear to be hydrogeologic subdivision VI, the Kirschberg evaporite member of the Kainer Formation; and hydrogeologic subdivision III, the leached and collapsed members, undivided, of the Person Formation. The most porous and permeable rocks of...
Authors
Ted A. Small, Allan K. Clark
Geologic framework of the Edwards Aquifer and upper confining unit, and hydrogeologic characteristics of the Edwards Aquifer, south-central Uvalde County, Texas Geologic framework of the Edwards Aquifer and upper confining unit, and hydrogeologic characteristics of the Edwards Aquifer, south-central Uvalde County, Texas
The stratigraphic units of the Edwards aquifer in south-central Uvalde County generally are porous and permeable. The stratigraphic units that compose the Edwards aquifer in south-central Uvalde County are the Devils River Formation in the Devils River trend; and the West Nueces, McKnight, and Salmon Peak Formations in the Maverick Basin. The Balcones fault zone is the principal...
Authors
Allan K. Clark, Ted A. Small
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government