Geology of DDRS
The geological features of the DDRS are highly varied and the topography is complex. The uplands in the western part of the site consist primarily of desert pediments overlying the Oligocene Tascotal Mesa Formation and the Mitchell Mesa Welded Tuff, which is dated at about 32 mya. Both units are the product of volcanic activity in the Chinati Mountains far to the west. The eastern part of the site includes an extensive exposure of the Eocene to early Oligocene Devil’s Graveyard Formation, which is approximately 235 m (750 ft) thick below a north-south trending escarpment. These layered fluvial and lacustrine volcaniclastic sediments are now being eroded into badlands-type topography by water and wind. Two forks of Alamo de Cesario Creek cut through the property and have created typical desert arroyos, buttes, mesas, alluvial fans, and hoodoos. The southern part of the DDRS is transected by a major east-west trending faultline, the Tascotal Mesa Fault. South and west of this fault are outcrops of the Rawls Basalt, produced 28 mya by volcanic activity in the Bofecillos Mountains.
The DDRS provides many opportunities for learning and research in the Geosciences. Though there are a several publications dealing with the geology of the area, comprehensive mapping and description of the rock units on the property have yet to be undertaken. Mapping can be accomplished through a combination of remote sensing and field mapping techniques, enabling units on the property to be correlated to those found nearby. Description of the different rock types through petrographic and quantitative elemental analysis will further enhance understanding of the processes that shaped the geology of the area. With its highly variable and unique setting, the DDRS is an ideal outdoor laboratory for geosciences as well as environmental science majors. Field trips to the property have been and will continue to be conducted in conjunction with courses and research projects. In addition, the varied geology of the DDRS makes the site ideal for hosting a Geology Field Camp, which would involve students from MSU and other universities. Field camp, a six credit-hour course covering 6-8 weeks of practical field experience, is required for most geology majors across the country.