Earth and Planetary Sciences ETDs

Publication Date



The Salado Formation, a member of the Ochoa Series, is a bedded salt deposit which is found in the Delaware Basin southeastern New Mexico and west Texas. It is comprised primarily of halite and sylvite with minor amounts of sulfate minerals. Rubidium-strontium age determinations of the evaporite minerals in the Salado indicate an age of final equilibration of 214 15 m.y. This age is fairly consistent with the geologic age of the formation, precluding substantial alkali-alkaline earth migration since deposition. Polyhalite and anhydrite samples from the Salado give / values of about .7078, which are consistent with reported valued for Permian seawater. The REE and trace element concentrations of the polyhalite and anhydrite samples are very low, reflecting and composition of seawater.

Rabidium-strontium age determinations of the clay minerals extracted from the salt suggest a minimum age of 390 77 m.y. This age probably represents the minimum age of the provenance of the clay minerals. The REE and trace element concentrations as well as the mineralogy of the clay minerals indicate a detrital origin for the clay minerals with some clay-brine interaction. Clay minerals seem generally depleted in the light REE (relative to NAS) which most likely were replaced by and from the evaporitic brines.

Degree Name

Earth and Planetary Sciences

Level of Degree


Department Name

Department of Earth and Planetary Sciences

First Committee Member (Chair)

Douglas Gridley Brookins

Second Committee Member

Roger Yates Anderson

Third Committee Member

Gary Perrin Landis



Document Type


Included in

Geology Commons