STRATIGRAPHY AND DEPOSITIONAL ENVIRONMENT OF SAUROPOD DINOSAUR TRACK SITES, LOWER CRETACEOUS GLEN ROSE FORMATION, COW HOUSE CREEK CENTRAL TEXAS

Although hundreds of isolated dinosaur tracks have been documented in the Cretaceous rocks of Texas, few sauropod trackways occur. Two sauropod trackways have recently been documented in the hard, resistant Glen Rose Limestone exposed by Cow House Creek just south of Gatesville (Coryell County), Texas. The first track site contains 17 tracks that trend southeast. The second track site, identified by examining 2012 imagery from Google Earth, has been covered by shallow water since fall of 2012, but contains 21 tracks that trend southwest to southeast. This research focuses on identifying the stratigraphic position and depositional environment of the sauropod trackways in Coryell County, Texas.

A total of 14.5 meters of section have been measured, varying in lithology from limestone to marl and calcareous shale. All three members of the Glen Rose Formation are present in the outcrop (the lower Glen Rose, the Thorp Springs, and the upper Glen Rose members). The track-bearing layer occurs in the lower Glen Rose member. The depositional environment varies from supratidal to intertidal and subtidal zones. The tracklayer appears to have been deposited in the supratidal zone. The most likely trackmaker was Sauroposeidon.