The Allamoore district of Hudspeth and Culberson counties, Texas, has become one of the most significant talc-producing areas of the United States. Exploitation of talc deposits in the district began in 1952 with a cumulative production of 120,000 tons through 1957 (Flawn, 1958).

The Texas Coastal Zone is marked by diversity in geography, resources, climate, and industry.

This field guide is designed to provide an opportunity to observe a variety of facies that are the fundamental blocks with which principal depositional systems have been fabricated. Available data is provided and a genetic interpretation is proposed.

The Fredericksburg Group is one of three groups of rocks which comprise the outcropping Lower Cretaceous sediments in north central Texas. Four formations form this group; from the base upward these are the Paluxy, Walnut, Comanche Peak and Edwards (fig. 1).

The West Chinati stock, well exposed in San Antonio Canyon and immediately westward on slopes of the southwestern part of the Chinati Mountains, Presidio County, Texas, is a large stocklike body of porphyritic hornblende granite cut by numerous dikes and irregular-shaped plutons of rhyolite, rhyo

Geologic map that depicts surface geology of Tarrant, Dallas, Kaufman, Ellis, Johnson, Somervell, and Rockwall Counties and parts of Parker, Hood, Erath, Bosque, Hill, Navarro, Henderson, Van Zandt, and Hunt Counties, Texas.

Endemic ammonite faunas evolved from cosmopolitan faunas in a series of successive episodes over about 35 million years of the Cretaceous of the Gulf Coast of the United States.

Basic geologic, hydrologic and engineering criteria on which selection of sanitary landfill sites should be based include (1) thickness, excavation characteristics, permeability, solution-holding capacity, and reactivity of host and cover materials; (2) hydrologic properties including depth to wa

Regional surface and subsurface studies indicate that thick deltaic (Queen City Formation) and thin shelf (Reklaw and Weches Formations) sequences compose the stratigraphic interval between the top of the Carrizo Sand and the base of the Sparta Formation.

The Van Horn-Sierra Blanca region lies athwart part of the boundary between two contrasting geologic provinces. The contrast between these two provinces, splendidly displayed by Holocene landforms in the present map area, has a history that dates back to at least Late Precambrian time.