148 ECONOMIC GEOLOGY OF SLLVERTON QUADRANGLE, [bull.182. 
sericite, and other secondary products by the action of the vein solu- 
tions. A close study of all exposures of such conjugations of the 
veins of the two groups failed to show any evidence of different age. 
The filling of both sets of veins is continuous, as it would be in syn- 
chronously filled branches of a single fissure, or is separated by a 
clay gouge due to subsequent movement. As far as is known, there 
is no continuation of the lodes of the second group north of the Silver 
Lake lode. A single small vein (the Jim Owen), shown in fig. 2, 
has been prospected for a short distance northward from the Silver 
Lake lode, but it is very improbable that this represents the continua- 
tion of any of the productive lodes south of the latter. If the Silver 1 
Lake lode were, as is supposed by the miners, younger than the lodes> 
of the second group, the absence of the latter on the northern side of i 
the intersecting lode could be accounted for only on the assumption! 
that the Silver Lake fissure is a fault of at least 2,500 feet throw. 
The entire evidence of the region, however, as is elsewhere shown,, 
indicates that the fissures now occupied by productive ore bodies 
were not formed by large faults, but on the contrary often reveal no 
appreciable displacement of their walls. 
The relation of the lodes of the second group to the great Titusvilh 
lode on the south are not so well known as in the case of the Silvei jj 
Lake lode on the north. The lodes in this portion of the basin ar( 
imperfectly exposed and have received very little undergrounc 
exploration. 
The ore bodies of the lodes of Group II have not been worked ii 
such a manner as to give any very definite data as to their dimension 
and shapes. In nearly every slope considerable masses remain wliic] 
are regarded as pay ore. The pay shoots are supposed to pitch north 
ward, but it is by no means certain that there is any regularity i 
their pitch. 
In addition to the main lodes a great number of smaller fissure 
traverse the country rock, particularly west of the lake. The st 
of these minor veins ranges from 20° to 40° west of north. They 
nearly vertical, but one group of them sometimes exhibits a stee 
northeasterly dip, while another group dips southwesterly. The iatt< 
case appears to be more common. They are often so closely space< 
a few feet apart, as to produce a conspicuous sheeting of the count) 
rock. This spacing does not exhibit any regularity or recognizab 
rhythm in its occurrence. Many of these fissures are ore bearin 
and it is not uncommon to see on a clean exposure of rock a stringe 
an inch or so wide, consisting of quartz next the walls and solid galei 
in the medial portion. Such mineralized stringers can be seen 
branch or to wedge out completely in the rock and be succeeded 1 
an overlapping stringer a short distance to one side. On a smj 
scale they repeat the phenomena to be observed underground in t 
larger veins of the second group. They are believed to belong to t 
same system and to have been formed at the same time as the latt« | 
ure 
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