60 
BULLETIN 61, TJ. S. DEPARTMENT OF AGRICULTURE. 
The accumulation of sodium sulphate in the center is of interest. The absence of 
potassium compounds in the brine and the low content in the marginal deposits are 
conspicuous. The accumulations in Sevier Lake are undoubtedly due to compara- 
tive recent action. Deeper bores would have revealed more of the history of the 
basin and perhaps beds of salines characteristic of the Bonneville period would have 
been discovered. 
BLACK ROCK DESERT, NEVADA. 
The Black Rock and Smoke Creek Deserts are of notable extent. The northern 
extension of Lake Lahontanoccupied this area, but no surface deposits of salines have 
been discovered. Some saline crusts can be found, but these are of little importance. 
A 500-foot well was put down at Sulphur, on the line of the Western Pacific Railroad 
and on the edge of the mud flat, but neither oil nor salines were found. West of 
Gerlach, salt is produced in small quantities by the evaporation of brines obtained from 
shallow wells. 
But few data of a chemical nature are available for this area. In the vicinity of 
Gerlach samples of mud were obtained from a shallow auger hole. From the same 
vicinity water samples were also obtained. The analytical results are given below. 
The muds show a high content cf salines, and these consist of chlorides and sulphates, 
together with small quantities of carbonates. The potassium content is about what 
would be expected. The mud is a tenacious clay. The waters are somewhat similar 
in composition to the salines contained in the clays. 
Analyses of saline crust and muds from the Black Rock Desert, Nevada. 
Sample and depth. 
. Percentage of total soluble salts. 
Total solu- 
Ca. 
Mg. 
Na. 
K. 
C0 3 . 
[ 
HCO3. S0 4 . CI. 
ble salts. 
P.ct. 
1.56 
.78 
.71 
.63 
.68 
P.ct. 
0.02 
.02 
.03 
.02 
.03 
P.ct. 
34.41 
35.90 
36.09 
36.32 
36.48 
P.ct. 
1.12 
2.32 
2.06 
2.28 
2.33 
P.ct. 
0.05 
.16 
Tr. 


P.ct. 
0.10 
.33 
.66 
.49 
.35 
P. ct. P. ct. 
21. 36 40. 99 
P.ct. 
59.68 
Muds: i 
0-1.25 feet 
6.85 
7.84 
4.97 
4.07 
53.63 
52.57 
55.37 
56.03 
18.31 
1.25^-2.5 feet 
23.19 
2.5-3.75 feet 
24.83 
3.75-5 feet 
34.47 
1 Average ratio Na to K in muds is 16. 
Analyses of waters from the Black Rock Desert, Nevada. 
Sample. 
Percentage of total solids on evaporation. 
Solids on 
Ca. 
Mg. 
Na. 
K. 
C0 3 . 
HCO3. 
SO*. 
CI. 
tion. 
"Water from surface trench 
P.ct. 
0.48 
2.11 
2.48 
P.ct. 
0.08 
.06 
Tr. 
P.ct. 
36.03 
32.08 
32.63 
P.ct. 
1.49 
2.73 
2.70 
P.ct. 
0.10 
.19 

P.ct. 
0.46 
2.97 
1.35 
P. ct. 
4.64 
8.13 
11.25 
P.ct. 
55.11 
47.57 
47.93 
Parts per 
100,000. 
5,209 
428.4 
Boiling hot spring 
444 
[Saline clays and crust from point 1.5 miles northeast of Gerlach, Nev. Watei from surface trench from 
same place. Samples by W. S. Palmer; analyses by J. A. Cullen.j 
The waters from the "four springs averaged were taken 0.25 mile from Gerlach. The temperature of 
these springs ranged from 16.1° to 32\2° C. Samples by W. S. Palmer: analyses by S. C. Dinsmore. 
The boiling spring was three-fourths mile northwest of Gerlach. Sample by W. S. Palmer: analyses 
by J. A. Cullen. 
BURIED DEPOSITS OF SALINES. 
The deposits resulting from the desiccation of Searles Lake are exposed on the 
surface and their discovery was a simple matter. Geological reasoning indicates 
that the conditions exemplified by Searles must have been repeated at other places 
in the Great Basin. Evidences of Quaternary lakes are to be found in a number of 
places, but not in all places do we find the expected saline deposits. The largest 
Quaternary lake basin, excepting Bonneville, is Lahontan, and it is now occupied 
by Pyramid, Walker, Humboldt, Carson, and Winnemucca Lakes. Unlike Mono, 
