WOODMAN: GOLD-BEARING SLATES OF NOVA SCOTIA. 
385 
■cleavage, but departing from that relation gradually towards the 
top and bottom. The metals within the vein, and even on contacts 
between gangue and country-rock, have not shared in the general 
distortion, and thus appear to have been protected by their relations 
to the resistant quartz. The cleavage planes of the calcite in the 
veins are often curved; but it is not possible at present to designate 
which of the various orogenic forces concerned in the history of the 
series produced the result. 
Structure. — The whole series of rocks is folded in a direction 
averaging N. 65° E. in Halifax county, becoming more northerly in 
the western part of the Province. It is noticeable that the general 
trend of the peninsula also changes correspondingly. The force 
producing these plications probably came from the south, although 
the evidence on this point is not clear. A second folding took place 
subsequently in a direction nearly at right angles to the former, 
■culminating in an extensive series of faults, which strike roughly 
north-south. These newer flexures are said to be less frequent in 
the eastern portion of the field, and to become gradually more 
Abundant westward. They have been equally instrumental with 
the earlier ones in locating the present mining settlements, by 
doming veins up so that denudation has given intermittent expo¬ 
sures. 
The faults are both normal and reverse. As they were formed 
in the main by pressure, the latter are most abundant, and tension 
or gravity faults afforded local relief. In places their magnitude is 
considerable, the throw being several hundred feet. Most of them 
belong to the end of the second period of folding, and those formed 
as a result of the first plications are small. 
The structures produced by these orogenic processes can be seen 
in most of the mining districts. Oldham, Renfrew, and Moose 
River Mines are cases in point. The first two have been mapped 
in a general way (Hind, ’72) . Of the last, a detailed map on a 
scale of I : 3,000 has been published by Mr. Faribault of the 
Geological survey of Canada. 
In many places the bedding is smooth but in many others it is 
disturbed by corrugations, which vary from minute crenulations up 
to “rolls” several feet from crest to crest and two or more in 
depth. The large cases are known locally as “barrel quartz,” and 
from smallest to largest are all the same in character and in origin. 
They start in veins, and are participated in by them and the adja- 
