Precambrian and Paleozoic stratigraphy; Franklin Mountains, west Texas
The Franklin Mountains are located in far West Texas (ElPaso County) and southernmost central New Mexico (Dons Ana County). The range, when including the North Franklin Mountains (north of Anthony Gap), is 23 mi (38 km) long and less than 5 mi (8 km) wide (Fig. 1). It consists of a linear series of north–south-trending, westward-tilted fault blocks, which are bounded on the east and west by major normal faults. Gravity slides are common throughout the range. The mountains are reasonable examples of the basin-and-range structural and physiographic type. The structure is distinctly different from the thrusted (autochthon and three allochthons) Cretaceus sequence of the northern Chihuahuatrough of the Sierra de Juarez to the south in Mexico. The Texas lineament, the major structural feature separating these disparate northern and southern structural styles, if it exists, would pass through downtown El Paso. Access to the area is by 1-10. Three localities are suggested for examination (Fig. 1). Localities 1 and 2 are on paved, public thoroughfares. Locality 3 (Vinton Canyon) maybe reached from 1-10 at Westway, approximately 3 mi (4.8 km) south of the Texas-New Mexico line, byproceeding eastward on a dirt track toward the mountains. A high-clearance vehicle is required.