TOPOGRAPHIC FEATURES OF THE DESERT BASINS. 41 



THE PANAMINT BASIN. 



The Panamint Valley occupies the southern portion of the trough east of that of the 

 Owens Valley, being the second trough east of the Sierra. It has two tributary valleys, 

 the Leach Valley in the southeast corner and a part of the Coso Valley to the north- 

 west, from both of which the drainage is still entirely open. The floor of the Panamint 

 is divided by a low alluvial divide into two sections, each of which contains a playa, 

 the northern one having a present or very recent drainage into the southern. Both 

 of these playas are saline, the southern one especially so. Stream decay has also pro- 

 duced a number of small local playas in both ends of the valley, all of which are 

 recent and unimportant. 



The most interesting feature in the topography of the Panamint is the possible former 

 drainage from the Searles Basin, as discussed above. However, as there noted, this 

 inflow was at most very brief and has probably not affected very greatly the geochem- 

 ical history of the valley. Excepting the pass into Searles all outlets from the 

 Panamint are high and all are far above any possible lake level. The history of the 

 valley has been essentially one of independence. The present drainage areas of the 

 various playaa are impossible of accurate estimation. Very seldom is there any 

 drainage at all. The total area of the basin is 1,950 square miles, including all tribu- 

 taries except Searles. Including Searles and Owens the area would be 6,800 square 

 miles, but it must be remembered that this greater area was tributary to the Panamint 

 only very transiently, if at all. 



THE SALINE VALLEY. 



The Saline Valley occupies what is essentially a northern extension of the Panamint 

 trough, though cut off therefrom by a prominent cross uplift. The basin is entirely 

 surrounded by high structiu"al divides, the lowest pass being nearly 4,000 feet above the 

 deepest depression. There is no possibility of overflow since the basin has had its 

 present structure. In the southeast corner of the basin are two small subsidiary basins, 

 previously tributary, but now cut off by stream decay and alluvial damming. One of 

 these contains a playa known as the Racetrack. The other contains a very small 

 playa unnamed. The deepest depression of the Saline Basin is occupied by a very 

 saline playa having an area of about 12 square miles and carrying a deposit of common 

 salt, the commercial exploitation of which is now being attempted. The area of the 

 basin, including the small subsidiary basins above mentioned, is 845 square miles. 



THE EUREKA BASIN. 



The Eureka Basin lies just north of the Saline Valley (last discussed) and is very 

 similar thereto, except that the only playa it contains is small and not saline. The 

 lowest pass is over 2,000 feet above the present bottom, all divides are structural and 

 ancient, and there is no possibility of overflow dxu-ing or since the Lahontan period. 

 This basin and the Saline Valley are perhaps the best and simplest known examples 

 of the inclosed basin of structural origin, and would probably well repay careful 

 scientific study. 



Cowhorn Valley, in the mountains west of the Eureka Basin, is now cut off behind a 

 low alluvial divide, but was formerly tributary. Including this, the area of the 

 Eureka Basin is 590 square miles. It is probable that the Deep Springs Valley (next 

 below) was also tributary to the Eureka during Lahontan time. Including it, the 

 total area is 775 square miles. 



THE DEEP SPRINGS VALLEY. 



West of the northern end of the Eureka Valley lies the similar, though smaller, basin 

 of the Deep Springs Valley. In the main, the surrounding divides are high and struc- 

 tural, but the eastern wall of the basin is breached by the narrow canyon of Soldier 



