152 ECONOMIC GEOLOGY OF SILVERTON QUADRANGLE, [bull. 182. 
such an irregularity as might be expected near the lower edge of the 
large horse which divides the lode on this level and the one above. 
(2) Strike faults, essentially parallel with the lode, are more con- 
spicuous in the case of the Silver Lake than in the other lodes of the 
mine. They are indicated by gouges, often of considerable thickness, 
on foot or hanging-wall, and by sheeting of the country rock when 
accompanied by soft gouge. Their effect upon the lode is well seen 
near the northwest end of level 2, where there is a pronounced strike 
fault on the hanging-wall side of the vein associated with approxi- 
mately parallel slips within the country rock of the hanging wall. 
The lode here is crushed and contains much clayey gouge. The char- 
acter and amount of the movement could not be determined in any 
case. It is believed, however, to have been in the main oscillatory, 
with but little net displacement. Had it been otherwise it would be 
very difficult to account for the present relation of the Silver Lake 
N9 3 Lever 
Fau/f 
Fro. 11.— Sketch section across the Silver Lake lode between levels 1 and 2, showing probable 
faulting of the lode by a flat strike fault. 
lode to the lodes of Group II and for the absence of gouge or other evi- 
dence of recent movement in certain portions of the former lode. 
(3) Strike faults making a considerable angle with the plane of the 
lode are not common on the Silver Lake lode. The best example of- 
this form of dislocation was noted in a large stope between levels 1 
and 2. The fault here is nearly horizontal and cuts both branches of 
the Silver Lake lode near the apex of the horse which divides them. 
The dislocation is a thrust fault with about 12 feet throw. The 
character of the fault and its result upon the ore body are shown by the 
accompanying sketch section across the stope (fig. 11). This fault 
appears to die out within a comparatively short distance to the south- 
west, as it was not noted on the stopes of the Royal and Stelzner lodes. 
(4) Irregular fracturing of the lode includes those minor disloca- 
tions which it has not been found possible to group according to any 
prevailing regularity of direction. They are often directly connected 
with the more regular fissures and are of small importance. 
