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Mylonitic Breccia near the Gunsight Formation

Detailed Description

Mylonitic breccia in alluvium of Little Deer Creek, downstream from a moderately west-dipping contact between biotitic quartzite of the Gunsight Formation, which is structurally overlain by garnet-chloritoid-bearing banded siltite of the banded siltite unit of the Apple Creek Formation. That structural contact is interpreted as a thrust fault, and this mylonitic breccia probably is from that thrust fault.


Public Domain.