This report describes the three-dimensional distribution of hydraulic conductivity in the Edwards aquifer from Kinney to Comal Counties, Texas.

The Upper Cretaceous Olmos Formation in South Texas continues to be an active exploration target 60 years after oil was first discovered in this clastic assemblage. The shallow, oil-bearing formation was deposited on a broad, wave-influenced shelf. Sand accumulated in two depocenters.

The Smackover and lower part of the Buckner Formations (Oxfordian) comprise a thick regressive sedimentary sequence deposited on a Jurassic carbonate ramp. Four major depositional systems are recognized: (1) basinal, (2) low-energy open shelf, (3) high-energy shoal, and (4) sabkha.

The Sligo and Hosston Formations of Aptian age occur over thousands of square miles in the subsurface of South Texas.

Upward-coarsening sandstone units of the Upper Cretaceous San Miguel Formation in South Texas were deposited in wave-dominated deltas during minor regressive phases, periodically interrupting a major marine transgression.

Geologic map that depicts surface geology of Kinney County and parts of Terrell, Val Verde, Edwards, Real, Uvalde, and Maverick Counties, Texas.

Oversize color geologic map that depicts surface geology of Dimmit, LaSalle, and McMullen Counties and parts of Maverick, Zavala, Frio, Atascosa, Karnes, Wilson, Live Oak, Jim Wells, Duval, and Webb Counties, Texas. The 6-page booklet indicates geologic formations, abbreviations, and ages.

This report is a compilation of all available data on mineral resources (exclusive of oil and gas) in 39 south Texas counties. Information from published and unpublished sources was checked and supplemented by field investigations.

Uvalde County is located in southwestern Texas, including part of the north margin of the Gulf Coastal Plain and the south margin of the Edwards Plateau. Its principal mineral resources are asphalt rock, clay, limestone, gravel, trap rock, and surface and underground water.