78 GEOLOGY OF ASPEN MINING DISTRICT, COLORADO. 
varying in position from that of the Silver fault. ‘This movement, repre- 
sented by the Clark fault, is therefore very nearly parallel to the bedding, 
and is also very close to the Silver fault, into which it probably merges 
both to the north and to the south. This third faulting was entirely sub- 
sequent to the ore deposition and to the Silver and Della systems of faults, 
both of which it faults wherever it intersects them. 
RED MOUNTAIN. 
This mountain, which lies immediately northwest of Smuggler Moun- 
tain and on the other side of Hunter Creek, is made up almost entirely of 
uniformly west-dipping sandstones and grits of the Maroon formation It 
offers, so far as known, no complications in geological structures ‘There is 
no folding, and what faulting may exist is obscured by the uniformity of 
the beds. No mineral deposits have been discovered on Red Mountain, and 
there is no great probability of any ever being found. There is a popular 
notion, however, that this mountain lies in the same belt as West Aspen 
Mountain, on which large deposits of ore have recently been found. This 
idea arises from the fact that Red Mountain is situated directly opposite 
West Aspen Mountain on the north side of the Roaring Fork; thus it has 
been supposed to have the same relation to West Aspen Mountain as has 
Smuggler Mountain to the eastern part of Aspen Mountain. Across 
Smuggler Mountain and East Aspen Mountain there is a continuous belt of 
mineral-bearing rocks, and the same has been thought to be true of West 
Aspen and Red mountains. It is clear, however, that West Aspen and Red 
mountains are in totally distinct geological formations, and that the corre- 
spondence in position is due to the domelike uplifting and synclinal folding 
of Aspen Mountain, which does not extend across Roaring Fork to the 
north. There has been a small amount of exploration for ore on Red 
Mountain, and some of the workings have cut belts which show a slight 
amount of mineralization, but the character of the rock is not favorable to 
such extensive mineralization as has occurred in the limestone and dolomites 
of the underlying formations. 
Pl. II is from a photograph of Red Mountain taken from the foot 
of Aspen Mountain. The rounded or flattened summit is due to glacial 
action, for on top there is considerable morainal material, consisting mostly 
of granite and quartzite which is derived from the other side of Hunter 
