Skip to main content
U.S. flag

An official website of the United States government

Paleocene coal deposits of the Wilcox group, central Texas

January 1, 2011

Coal deposits in the Wilcox Group of central Texas have been regarded as the richest coal resources in the Gulf Coastal Plain. Although minable coal beds appear to be less numerous and generally higher in sulfur content (1 percent average, as-received basis; table 1) than Wilcox coal deposits in the Northeast Texas and Louisiana Sabine assessment areas (0.5 and 0.6 percent sulfur, respectively; table 1), net coal thickness in coal zones in central Texas is up to 32 ft thick and more persistent along strike (up to 15 mi) at or near the surface than coals of any other Gulf Coast assessment area. The rank of the coal beds in central Texas is generally lignite (table 1), but some coal ranks as great as subbituminous C have been reported (Mukhopadhyay, 1989). The outcrop of the Wilcox Group in central Texas strikes northeast, extends for approximately 140 mi between the Trinity and Colorado Rivers, and covers parts of Bastrop, Falls, Freestone, Lee, Leon, Limestone, Milam, Navarro, Robertson, and Williamson Counties (Figure 1). Three formations, in ascending order, the Hooper, Simsboro, and Calvert Bluff, are recognized in central Texas (Figure 2). The Wilcox Group is underlain conformably by the Midway Group, a mudstone-dominated marine sequence, and is overlain and scoured locally by the Carrizo Sand, a fluvial unit at the base of the Claiborne Group.

Publication Year 2011
Title Paleocene coal deposits of the Wilcox group, central Texas
Authors Robert W. Hook, Peter D. Warwick, John R. SanFilipo, Adam C. Schultz, Douglas J. Nichols, Sharon M. Swanson
Publication Type Book Chapter
Publication Subtype Book Chapter
Series Title AAPG Studies in Geology
Index ID 70192679
Record Source USGS Publications Warehouse
USGS Organization Eastern Energy Resources Science Center