DEATH VALLEY, GENERAL GEOLOGY. 
Analysis of soil from heath Valley. 
Per cent. 
Chloride of sodium 
Chloride of potassium 
Sulphate of sodium 1 :;. 53 
Sulphate of calcium (hydrou's) . 7;) 
Moisture . 14 
Undissolved residue (gypsum and clay) 
This large supply of salt, while at present, as Campbell states, too 
impure to be of commercial value, may in the future be economically 
important. From 1883 to 1887 an extensive plant extracted borax 
from the salts of this marsh, but on the discovery of extensive 
colemanite deposits in the Tertiary lake beds on Furnace Creek it 
was closed down. Borax is also reported in the clay of the plava 
2 miles east of south of Surveyors Well. 
Death Valley is one of the best watered areas within the limits 
of the area here discussed, and the water for the most part is good. 
Salt Creek and the warm Indian Springs have already been described 
(pp. 19, 20). At Stovepipe Wells, Surveyors Well, Ruiz Well, Salt 
Creek Wells, and the water hole on the Furnace Creek road, 1 mile 
north of the boundary of this area, water stands in shallow holes dug 
in the sand and clay. The water of the last-named hole is too salt for 
man's use, although animals will drink it. Mesquite Spring is a small 
spring in Recent gravels, while the water of Cow Creek and Triangle 
Spring Hows from Tertiary lake beds. 
GENERAL GEOLOGY. 
SEDIMENTS. 
General statement. — Two sedimentary series much later in age than 
the Paleozoic rocks of the Amargosa and Panamint ranges outcrop 
in Death Valley. The one is composed of coarser fragmental mate- 
rial, well rounded, and appears to have been deposited in a wave- 
swept lake, while the material of the other is angular or subangitlar 
and evidently analogous in origin to the present alluvial slopes and 
fans. Associated with each are finer grained clays and limestones— 
those of the one series, lake deposits; those of the other, playa de- 
posits. The delineation of these finer deposits on the map is in many 
cases probably inaccurate. The lake deposits are clearly older than 
those of the playa and are better cemented and in general more 
deformed. The two formations, while less extensively developed, 
are much more easily differentiated on the east side of the Amargosa 
Range and in the adjoining portions of the Amargosa Desert, where 
the detrital and playa deposits are uncemented angular gravels, clays. 
and chemically precipitated limestones, which are particularly undo 
