Lower Cretaceous sands have long been important aquifers in Central, North-Central, and North Texas. In recent years these sands also have been sources of high-silica industrial or specialty-purpose sand. Lower Cretaceous sands of northern Texas and Cenozoic sands of the Texas Coastal Plain comprise the main resources of high-silica sands in the State. Knowledge of their occurrence, distribution, stratigraphic relation, quality, and suitability for industrial uses is necessary to their future development.

Regional investigation of the lower part of the Wilcox Group in Texas in outcrop and subsurface indicates seven principal depositional systems. These include: (1) Mt.

This report deals with the occurrence and potential production of industrial sand in the Gulf Coast area of Texas. The study area covers approximately 23,000 square miles underlain by alluvial, deltaic, beach, and eolian deposits of Pleistocene and Recent age. Deposits are intermixed and interbedded sands, gravels, silts, and clays. Sand bodies are irregular in size and shape depending on environment of deposition; they vary in physical character and mineralogical and chemical composition.

Limestone is one of the most important nonfuel mineral resources in Texas. Annual production exceeds $30 million; value added in the manufacture of such products as cement and lime amounts to about $100 million annually. Lower Cretaceous limestone is the source of more than 40 percent of the State's total production of limestone and is utilized chiefly as crushed stone (aggregate and constructional stone), sources of raw materials for lime and portland cement, chemical and industrial process stone, agricultural limestone, fluxstone, and dimension stone.

This report treats the sedimentary petrology and history of the Haymond Formation, a monotonous sequence of interbedded sandstone and shale that has a maximum preserved thickness of 4,300 feet. The upper part of the formation includes massive coarse sandstone beds and a complex of pebbly mudstones and slumped beds that encase exotic and erratic rock fragments up to 130 feet long. The Haymond is part of a 12,000-foot sequence of flysch that was deposited during late Paleozoic time in the Marathon geosyncline, a part of the Ouachita geosyncline located in Trans-Pecos Texas.