The Salt Domes of South Texas

Abstract

In south Texas, there are three known salt domes, Palangana, Piedras Pintas, and Falfurrias; three possible domes, Sal del Rey, Sal Vieja, and Chapeno; and two much less probable domes, Smith Corkill and La Lomita. The structure of Palangana, fairly well known from drilling, is that characteristic of an American salt dome, and is distinctly reflected in the topography. Palangana has no production. At Piedras Pintas, the salt and cap have been drilled into, but not much is known in regard to the structure of the dome. Piedras Pintas has a small, shallow oil field. Both domes gives evidence of the very great upthrust of the salt. On the basis of the evidence afforded by the German salt domes, the origin of salt domes is the plastic deformation of sedimentary salt beds. The rigin of salt domes is the plastic deformation of sedimentary salt beds. The origin of the cap, such as is present at both Palangana and Piedras Pintas, has not been satisfactorily explained, although several plausible theories have been proposed. At Falfurrias, the salt has not been encountered, but the presence of a characteristic salt-dome mound and characteristic cap rock indicate the presence of a salt dome. Sal del Rey and Sal Vieja are saline lakes whose topography in a general way is similar to that of a central-depression type of salt-dome mound. The lakes, however, are more probably due to wind activity with concentration of normal surface waters in the wind-scooped basins. Chapeno suggests salt-dome structure in the presence of sulphur deposits. La Lomita is a mound near the R o Grande, and Smith Corkill is a group of chalcedonic knobs.