POTASH SALTS AND OTHER SALIlsTES IN THE GREAT BASIN REGION. 43 



it more nearly approximates the ideal type described before than any other. It is a 

 circular basin of 232 square miles area, occupied by a playa of 3.2 square miles area. 

 The ratio of basin area to playa area is 72.5. It receives its principal underground 

 waters from the Sodaville-Mina Valley. Undoubtedly its history is similar to the 

 Silver Peak Marsh. The central area is occupied by a reddish-brown mud, locally 

 covered by efflorescences. In places the mud is dried to a brown, pulverulent soil, 

 containing more or less sodium chloride and small amounts of other salines. The 

 present movement of the salines from the deeper beds is taking place, first, by slow 

 upward movement of the water contained in the muds (caused by capillarity), and, 

 second, in the marginal portions by a slow movement upward caused by capillarity 

 and by the banking up of the water plane where it strikes the more or less impervious 

 mud bodies of the central playa. The water of the central area is saturated with 

 salines and deposits them as crusts at the surface. In the marginal portions the 

 underground water becomes more or less saturated as it passes through the beds and 

 carries saline material to the surface, where it crystallizes out. LeConte's idea in a 

 large measure is correct. His term "springs" would include seepage water in all its 

 phases of upward movement. Occasional heavy rainfalls produce sufficient run-off 

 to form a shallow lake. Such waters dissolve salines and concentrate them in the 

 central depression. Salt is the principal compound concentrated in this manner. 



A number of analyses were made upon samples of salines from this marsh, but 

 potassium in small amounts only was found. A sample of moist sand and salt from 

 the central part of the playa shows the following: 



Analysis of salt in sand from playa, Sample No. 15. 

 [Analysis by J. A. Cullen.] 

 Per cent. 



Ca-.-...; 1.20 



Mg 44 



K 3.03 



Na 30.39 



Per cent. 



SO4 47.68 



CI 14.17 



CO3 3.09 



Total soluble salts in sand 12. 15 



The analysis shows sodium sulphate and chloride in greatest amoimt. Minor 

 amounts of sodium carbonates and some potassium chloride are shown. The sodium- 

 potassium ratio is 10. No analyses of the brines are available. Excepting for the 

 borax and salt, this marsh is a very doubtful source of commercial salines. The potash 

 content is too low and its separation would be complicated by the presence of sulphates 

 and carbonates. 



Saline Valley, Into County, Cal. 



This is an inclosed basin. The central portion, of about 12,000 acres extent, is 

 covered by a salt crust 2 inches thick and beneath are muds saturated with brines. 

 When the crust is scraped off it renews itself in about 15 days. At almost any place 

 over the salt area at a depth of 2 feet salt brine can be obtained. In warm weather 

 the salt crystallizing out is pure; in cold, it contains small amounts of soda. The 

 salt deposits are being worked and preparations are being made on a large scale for 

 its shipment by the Saline Valley Salt Co. The regional rocks about this basin are 

 granites, limestones, and volcanics. Marsh borax was worked at one tingie in the 

 valley. 



A single sample of the salt crust from this valley was submitted and found to con- 

 tain 40.98 per cent soluble salts, and the soluble salts contained 4.2 per cent potassium. 

 Three brines and one spring water were also submitted. The analyses follow: 



Analyses of brines and spring water from Saline Valley. 

 [Per cent of total solids.] 



No. 



Ca. 



Mg. 



Na. 



K. 



CO3. 



HCO3. 



CI. 



SO,. 



Total solids 

 on evapo- 

 ration, parts 

 per 100,000. 



1 



. 10.0 



3.08 

 .37 

 .79 

 .73 



13.84 

 36.31 

 34.38 

 32.57 



Tr. 

 1.17 

 .73 

 .71 



Tr. 

 .07 

 Tr. 



Tr. 



7.64 

 .03 

 .15 

 .28 



24.62 

 48.78 

 48.70 

 45.45 



28.46 

 12.85 

 13. 37 

 17.30 



130 



2 



.18 

 1.55 

 2.97 



35,506 

 8,237 



3 



4 



4,238 







No. 1. Spring water. 



No. 2. Brine from center of flat. 



No. 3. Brine from pothole on south edge of flat. 



No. 4. Brine from pothole one-half mile east of No. 3, 



Analyses by J. A. Cullen, Bureau of Soils. 



