Upper Pensylvanian and lower Permian rocks of the Eastern Shelf in North-central Texas are composed of 10 to 15 repetitive sequences including open shelf, deltaic, fluvial, and interdeltaic depositional systems. Sediments derived from the Ouachita Mountains and associated piedmont were transported westward across a narrow coastal plain. Fluvial and deltaic sandstone fac1es define a southwest paleoslopc of about 5 feet per mile. Sandstone facies are delta front sheets, distributary mouth bars, distributary and fluvial channels, and destructional bars.

Geologic map that depicts the surface geology of Carson, Gray, and Wheeler Counties and parts of Moore, Hutchinson, Roberts, Hemphill, Potter, Randall, Armstrong, Donley, and Collingsworth Counties.

Papers in this volume were presented at the Fourth Forum on Geology of Industrial Minerals sponsored by the Bureau of Economic Geology, The University of Texas at Austin, on March 14 and 15, 1968. The program and meetings were organized and directed by co-chairmen W. L. Fisher and P. U. Rodda, Bureau of Economic Geology. Papers in this volume are arranged in the order of presentation at the meetings; contributions have been edited only as necessary to present a standard format. Mr. James Macon, Cartographer, and Mrs. Elizabeth T.

Geologic map that depicts the surface geology of Montgomery, San Jacinto, and Hardin Counties and parts of Madison, Trinity, Polk, Tyler, Jasper, Newton, Orange, Jefferson, Liberty, Harris, Waller, Grimes, Walker, and Robertson Counties. The 4-page booklet indicates geologic formations, abbreviations, and ages. This Sheet is a memorial to the late Harold Norman Fisk, distinguished geologist who was associated with Humble Oil & Refining Company at the time of his death in 1964. Dr.