THE EARTH MOVEMENT ON THE FAULT OF APRIL 18, 1906. 99 
At the San Andreas dam, the fault past thru a rocky knoll which serves as an abutment 
for the dam on both sides, the embankment being in 2 parts. The rocks were shattered 
and the road over the dam and the fence paralleling it were offset several feet in the 
usual direction. The ground here was traversed by several cracks, those on the south- 








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\ Gate house 

Scale in feet 
t) 100 200 3 

00 400 ae? 
é 
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et wee 
WASTE FLUME 



Scale in feet 
10 20 30 
Scale infeet 
100 

50 

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Fic. 36.— Intersection of San Andreas dam by fault. A. Plan of dam in two parts, with 
rock between. 8B. Relation of dam to waste weir tunnel. C. Detail of waste weir tunnel. 
west side of the fault branching southerly from it and those on the northeast side branch- 
ing northerly. Below the dam a heavy wooden flume on a trestle within 50 feet of the 
fault-trace was demolished for about 60 feet of its length. 
