Lusk Creek Subdistrict

The mines and prospects of the Lusk Creek Subdistrict are aligned along the Lusk Creek Fault Zone, which generally marks the northwestern margin of the IKFD (Figure 27). Arranged in a line more than 4 miles long, all these mines and prospects share a common structural setting. The fault zone is 500 to 1,000 feet wide, is nearly linear, and has an overall trend of N 35° E. Parallel high-angle, southeast-dipping reverse and normal faults compose the fault zone. These faults delimit central slices of Mississippian rocks that are older than the rocks on either side of the fault zone. Two episodes of faulting are thereby indicated. First, compressional stresses induced reverse faulting that raised the southeastern block. Relaxation and extension then induced normal faulting that lowered the southeastern block below its original position, creating the Dixon Springs Graben (Weller 1943c; Nelson et al. 1991). Most of the mineralization took place along the reverse fault on the northwest side of the zone.

The most detailed information on mines in the Lusk Creek Subdistrict comes from a series of unpublished reports authored by J.M. Weller to characterize mineral deposits during World War II. Written while several of the mines were active, these reports include large-scale geologic maps surveyed by pace and compass.