Corwin Springs Known Geothermal Resources Area, Park County, Montana. [General geologic description]

摘要

The Corwin Springs Known Geothermal Resources Area (KGRA) is contiguous to Yellowstone National Park along a part of the northern boundary of the park near Gardiner, Park County, Montana. The area contains two known sites of hot-spring activity: LaDuke Spring, 2.8 km southeast of the small resort community of Corwin Springs, and Bear Creek Spring, 2.6 km east of Gardiner. LaDuke Spring issues from brecciated quartzite and has a flow rate of 380 l/min, a surface water temperature of 65/sup 0/C, a silica-geothermometer temperature of 68.7/sup 0/C, and a Na-K-Ca geothermometer temperature of 76.8/sup 0/C. Bear Creek Spring issues from limestone and has a flow rate of 4 l/min, a surface water temperature of 32/sup 0/C, a silica temperature of 46.7/sup 0/C, and a Na-K-Ca temperature of 87.2/sup 0/C. The springs, which are actively depositing travertine, are on or near the trace of the Gardiner fault, a high-angle reverse fault which forms the southwestern boundary of the Beartooth uplift. The geological, geophysical, and geochemical data which contribute to the overall geologic delineation of the Corwin Springs Known Geothermal Resources Area are summarized.