64 REPORT OF THE CALIFORNIA EARTHQUAKE COMMISSION. 
earlier movements. A review of the facts indicates that the addition to the height of the 
old scarps and the total elevation of the new ones rarely, if at all, exceeded 3 feet. In 
general it was less than 2 feet. 
The distribution of the line of faulting for a typical stretch of the Rift near Fort Ross, 
_ the auxiliary cracks, the disposition of the 
scarps upon these, and the relation of the 
whole to the old Rift features, are well 
shown on map No. 3 by Mr. F. E. Matthes. 


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ne: The horizontal displacement is also indi- 
are cated on the map, but this needs more 
2” detailed statement. 
‘ On the line of the fault, about 300 
12497 12-7 1-1-10, yards northwest of the road from Sea 
i eawe View to Fort Ross, a steel water-pipe 
let25 “6 tr, Was dislocated by the earth movement, 
anes fo. “lz. and found to be offset 8 feet, the south- 
11+35 oe: . 
a ; west portion having moved northwest- 
Tren erly. This of course affords only a mini- 
mum measure of the relative movement. 
Where the road just mentioned intersects 
the fault-trace, both the road and the 
bordering fences were offset about 7.5 
feet, with a slight sag on the northeast 
side. The zone of shearing here was from 
10 to 20 feet wide. A wagon road on 
the Call ranch, south of the one above 
referred to, was offset 12 feet 3 inches, 
the line of dislocation being marked by 
an open fissure in the soil a few feet deep, 
and several short diagonal cracks, as 
shown in plate 36c. Another offset 
fence is shown in plate 36a, the displace- 
pute ment being here 8 feet at the fault-trace. 
ee The effects of the earth movement in the 
timber to the south of this are well shown 
in plate 344. Several large trees stand- 
ing on the fault line were split or torn 
asunder. The offset of the south line 
pp fence of the Call ranch was carefully 
surveyed by Mr. E. 8. Larsen, and the 
results of his survey are shown in fig. 15. The bearing of the fence is N. 36° E. He 
reports that for the first 1,000 feet from the southwest end of the fence the greatest 
error in alinement was about 1 inch, and that practically there was no deformation in 
this stretch. In the next 125 feet going northeast there was found a deviation from 
this alinement of 4 inches to the southeast. In the next 50 feet the deviation in 
the same direction was 7 inches more. In the next 140 feet the deviation in the same 
direction was 3 feet 7 inches more. Then came. the fault-trace with an abrupt displace- 
ment of the fence of 7 feet 5.1 inches. Northeast of the fault-trace the fence retained its 
line very well. In 100 feet it was out only 1 inch. Beyond this it enters the timber and 
its course is somewhat influenced by the larger trees, but maintains its line within a 
few inches. These measurements give a total horizontal displacement of 12 feet distrib- 

Fic. 15.— Offset of fence by 
fault at Fort Ross, showing 5440 Km | 
distribution of the deforma- 
tion on southwest side of 
fault. Scales: Along fence, 
1 inch = 200 feet. Normal to 
fence, 1 inch = 20 feet. 
