292 The American Geologist. May, 
uted to faulting, definite evidence of displacement is not al- 
ways discernible, it may be said that this is plainly because 
of the fault <urfaces having been eroded. Moreover, definite 
evidence exists at some points. For instance the steep north 
slope of the Silver Peak range is ascribed to faulting and along 
the north base of the range the lake beds of the Esmeralda for- 
mation are crumpled and broken and at some points stand ou 
edge, while a few kundred feet away they dip rather evenly 
to the north and north-east at angles of 20 degrees to 35 de- 
grees. A basalt dike for a short distance follows this E—W. 
fault. 
The Palmetto mountains likewise appear to have been ele- 
vated along an 1¢.—-\W. fault line, and along this line are sey- 
cral strong springs, and a dike of rhyolyte with an E.—W. 
course seems to iizve intruded along this fault zone. 
Smaller faults of the normal type are extremely abun- 
dant, and can be plainly seen at nearly all points where the 
rocks are arranged in lavers, as in the rhyolitic tuffs, and in 
tlie slates and sandstones of the Esmeralda formation. In the 
more massive igneous rocks as well, such faults are some- 
cumes apparent as in andesyte north-west of Cow Camp, the 
original groovings of the fault wall being still preserved as is 
shewn on Plate XVIU--B. 
Direction of the faults. In general it may be stated that 
many of the faults 1rend either N.—S. or E—W. 
Time of faulting. There is evidence that some of the Pal- 
eozoic beds were folded and displaced before the period of nor- 
mal faulting. These earlier disturbances perhaps occurred at 
the time of the intrusion of the granolytes. Much of the nor- 
mal faulting, however, appears to date from the close of the 
Tertiary. 1£:identiy, for example, the displacement along the 
north face oi the Silver Peak range must have occurred after 
the deposition of the Tertiary lake beds for they are involved 
in this disturbance. Probably faulting occurred well into Pleis- 
tocene time for the detrital materials of the early Pleistocene 
along the cast base of White mountain on the west side of 
lish Lake valley, appear to have been rather sharply uplifted 
along a N.—S. line. This fault line cuts across the older de- 
trital fans leaving scarps facing the valley. Other evidences 
of the uplift of the Pleistocene materials have already been _ 
noted under the head of “Pleistocene.” 
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