Jay A. Raney and Edward W. Collins, co-principal investigators; Thomas A. Tremblay, Rachel L. Waldinger, William A. White, and James C. Gibeaut

During the first quarter of 2004, work dealt with new mapping and completion of open-file geologic maps within the Hill Country Trinity aquifer near Kerrville and Bandera, Central Texas, and of the Christmas Point quadrangle-San Luis Pass area, Texas Gulf of Mexico coast. Other work during 2004 focused on a digital compilation mapping project for the Del Rio, Texas, area in South-Central Texas. Maps of the Hill Country Trinity aquifer area will be used to make decisions regarding aquifer management and modeling, land use, and environmental protection for Central Texas, a region where population growth is causing greater demands for use of water and Earth resources. The area straddles the east edge of the Edwards Plateau, the boundary between the Edwards-Trinity aquifer of the plateau and the Hill Country Trinity aquifer. The map of the Christmas Point quadrangle includes Holocene and Pleistocene environmental geologic units associated with coastal depositional environments within this important tidal-inlet area of the Texas Gulf Coast. It will support crucial activities, such as evaluating historic changes of coastal depositional environments, addressing erosion issues, educating the public, and establishing a framework for conducting studies and presenting data for management of other Texas inlets. The digital compilation map project encompasses a Rio Grande Border area that includes Del Rio, Amistad National Recreation Area, and major transportation routes from Mexico, as well as parts of two aquifers, the Edwards limestone aquifer and the alluvial Uvalde aquifer. The geologic map of the Del Rio area is intended to be used by professionals and laypersons as a source of general geologic information that relates to land and resource use and management. Mapping for these projects is supported by the STATEMAP program, part of the National Cooperative Geologic Mapping program administered by the U.S. Geological Survey for the production of geologic maps to augment the Texas and national geologic database, and includes collaboration with the Texas Water Development Board and the Texas General Land Office.


For more information, please contact Jay Raney, principal investigator. Telephone 512-471-5357;