When a reference is made to the mineral resources of Texas, most people think of oil and gas, and some few also of sulfur. And, of course, it is true that of the whopping $4.4 billion dollars’ worth of minerals produced in Texas in 1963, 92% was oil, gas, and natural gas liquids.

Since the days of R. T. Hill (1901) two Upper Cretaceous lithic units have been used as formations but have remained unnamed.

Minerals play a vital role in the economy of an industrial State. In Texas, where annual production of minerals currently amounts to more than $4.

Studies along the southern and southeastern borders of the High Plains have demonstrated the presence of outliers of fossiliferous Ogallala Formation in Borden and Scurry counties and have documented the occurrence of Pliocene deposition as far southeast as Sterling County.

Sediments of the Fredericksburg Division in south-central Texas were deposited on the slowly subsiding west flank of the Tyler basin. In this region there are three stratigraphically distinct areas. The southern area has a thick Edwards Limestone unit overlying a thin Walnut Formation.