The Twin Falls times. [volume] (Twin Falls, Idaho) 1905-1916, 1915-10-22
new FAULT THE CAUSE
Eartl's Crust Drops Twelve Feet for
Distance of Thirty Miles.

That the big earthquake which oc-
Cured on the night of October End,
was due to hitherto unknown fault
in the Sonoma range of mountains
along the foothills of Mount Tobin
sixty miles south of Winnemucca, is
the opinion of j. G. Jones. professor
of geology Of the state university.
Professor Jones and Professor
Boardman, of the engineering depart
ment of the university, arrived from
Reno Saturday morning and left for
Pleasant valley, accompanied by At
torney l.. G. Campbell, with Roy X.
Brown as driver of their auto They
returned last evening and Professors
Jones and Board left for Reno.
Speaking of their observations
along the fault or break in the earths
crust, which they examined from one
end to the other Mr. Campbell said
to representative of "The Star" this
morning.
'The northern end of the fault is
| in the foothills of Mount Tobin, about
three miles from Mud Springs, and
it extends continuously almost due
south about thirty miles to point a
few miles below the Cooper and
Uniacke ranch. At the southern end
the fault spreads out like a hand.
From distance the line of the
| break along the fault resembles a
railroad grade. Measurements of the
| fault showed it to be from twelve to
/ fifteen feet The angle of the fault
is 54 degrees, the dip being to the
west, the earth having movd in that
direction. The trend is almost due
north and south.
'In few places along the break
we find slickenslides, as found on
the walls of veins, proving the plane
of action. The slickens'ides showed
a slight movement of the sliding mass
to the north, hut ou" observations ci
/ tie break where it inte ',ucted fences
roads and irrigation bitches showed
the drop to be straight downward
in the valley and along the hill
sides near the Cooper and Uniackt
ranch there were many light frac
lures, not along the line of the fault
i These fractures were caused by thu
tremendous jar when the slip occur
red. This fracturing, occurring on thu
surface is seen for miles. Surface
water came up through these craks
and the ground had the appearance
) of being swept by an enormous cloud
burst.
From our examination we fount
no evidence of the great fault or slil
being the reopening of an old one
the conclusion being that the sill
: which caused the earthquake was !;
new one. However, there were indi
cations of old faulting above the new
break, the old fault scarp shown,
quite plainly.
Professor Jones, speaking of th'
probability of other earthquakes. will
this section as the center of distur
bance, gave it as his opinion tina
there is no danger and that it vii
probably be years before another sim
liar drop will occur on this faul
plane like those of the afternoon ant
| night of October End. He said tina
for two or three weeks, however, ligh
jars would probably occur, the re
suit of the settling of the great mas
of segemnts, which have to adjus
4 themselves after the great move
e ment which occurred. To this set
Y tling is due the light shocks whicl
5 have occurred since the big one O
: eight days ago.
S ut is probable that Professo
t Jones will come to Winnemucca a
e an early date and deliver publi
lecture on earthquakes, when he vii
fully and plainly explain what cause
: the great shake-up of October IN
= which he said was great enough
! violence to be felt in New York Cit.
: He also said that faults of the exten
: of the new one at Mount Tobin us,
i ally are about five miles in depth" :
VNinu o,n,,oeo