ASPEN SPECIAL MAP. 69 
ment took place at an early period before the ore deposition, while the rest 
of the fracture was undisturbed, and that the later movement, which was 
centralized in Tourtelotte Park, produced the Justice fault along the 
southern part of this fracture in postmineral times. 
East Aspen Mountain faults——Q)n the east side of Hast Aspen Mountain there 
comes in a series of nearly parallel faults, which extend continuously into 
the Tourtelotte Park district, where they are much more important than on 
Aspen Mountain, since they belong to the Tourtelotte Park system, which 
has its greatest development at a point farther south than the Aspen 
Mountain system, to which most of the faults on Aspen Mountain belong. 
These faults, as shown on Hast Aspen Mountain, have a general northwest 
trend, which is a slight variation from the normal north-south trend of the 
same faults, or of faults belonging to the same system, in the Tourtelotte 
Park district. With the change in trend on Aspen Mountain there is also 
a convergence, so that the various faults tend to unite, and after uniting, to 
die away. The amount of dislocation decreases steadily from the south 
toward the north, and on the north side of Kast Aspen Mountain, as is 
shown by the displacement of the Parting Quartzite, which is found to be 
nearly continuous in outcrop, the system comprises only two planes of 
shght faulting. Judging from these indications, it is likely that these faults 
die out very soon after leaving East Aspen Mountain, and it is probable 
that, like the Chloride and Bonnybel faults, they stop on reaching the 
Silver fault. No ore has been found along them on East Aspen Mountain, 
and in the Tourtelotte Park district it has been shown that they were 
developed subsequent to the period when the ores were deposited, and 
are, therefore, not at all mineralized. 
At the extreme southern end of the map, on Hast Aspen Mountain, 
there is shown one of the cross faults that are so common in the Tourtelotte 
Park district, which belongs to the general system of east-west postmineral 
faults that is there so conspicuously developed. In this case the fault has 
apparently brought the Silurian dolomite on the south side into contact 
with the Archean granite on the north side. 
Mary B. fault—'T‘he Mary B. fault is so named from its being cut in the 
Mary B. workings, which pass through the lower arenaceous limestone of 
the Maroon formation into the dolomite of the Silurian. In a tunnel which 
starts from near the bed of Castle Creek in Triassic sandstones and runs 
