Jurassic, Cretaceous, and Tertiary sediments in the East Texas Basin have been structurally modified by movement of Middle Jurassic Louann Salt.

Geologic map that depicts the surface geology of Nacogdoches, Shelby, San Augustine, Sabine, and Angelina Counties and parts of Anderson, Cherokee, Rusk, Newton, Jasper, Tyler, Polk, Trinity, Robertson, Madison, Leon, Freestone, and Panola Counties, Texas.

Geologic maps that depicts the surface geology of McLennan, Limestone, and Falls Counties and parts of Bosque, Hill, Navarro, Freestone, Leon, Madison, Robertson, Milam, Bell, Lampasas, Coryell, and Hamilton Counties, Texas.

Three closely spaced oblique-slip faults displace a Quaternary gravel and sand unit overlying Eocene Claiborne strata in the Trinity River Valley, Leon County.

Lignite development will place major demands on ground-water supplies.

Analysis during the second year was highlighted by a historical characterization of East Texas Basin infilling, the development of a model to explain the growth history of the domes, the continued studies of the Quaternary in East Texas, and a better understanding of the near-dome and regional hy

Oakwood Salt Dome in Leon and Freestone Counties, East Texas, is under consideration as a nuclear waste repository.

The third year of research was highlighted by the integration of regional basinal studies with growth histories for specific domes, studies of cap-rock diagenesis and salt deformation, preliminary studies of ground-water flow and geochemistry around Oakwood Dome, and preliminary studies of micros

Surficial geologic investigations at Palestine, Keechi, and Oakwood salt domes have provided information necessary for evaluating these domes as nuclear waste repositories. Diapir growth uplifted sediments to form domes and created complex radial faulting.

Principal fault systems in the East Texas Basin were examined in terms of their distribution, geometry, displacement history, and possible origins.