Ancient Lake Tecopa
The basin of former
Pleistocene
Lake Tecopa, in
southeastern Inyo County, Calif., is located in the Mojave
Desert about 32 km east of Death Valley The nearest large city
is Las Vegas, Nev., which is located about 97 km to
the east.
The town of Shoshone is located in the northern part of the basin, and the town of Tecopa is located in the southern part; Shoshone is on State Route 127, which runs generally north-south through the basin. The lake basin is bounded on the west by Dublin Hills, Ibex Hills, and the southern part of the Greenwater Range and on the east by the southern parts of the Nopah Range and Resting Spring Range. To the south are the Sperry Hills through which the Amargosa River flows, draining the study area. The lake beds cover an area about 18 by 23 kilometers.
Pleistocene Lake Tecopa in southeastern Inyo County, Calif., was formed when the Amargosa River was blocked at the southern end of its valley. The lake acted as a settling basin for detrital material being transported by the river. This detritus consisted of clays, quartz, feldspars, and micas which became mudstones and siltstones. These mudstones and siltstones, much eroded and dissected after the draining of the lake, extend over the entire basin and are interbedded with tuffs formed by the intermittent deposition of volcanic ashfalls in the former lake waters.
(USGS)
