In their study published in Lithosphere this week, James Kessler and colleagues examine the geology of a scientific borehole drilled into the Snake River Plain, Idaho, USA, to investigate the potential for geothermal energy at depth. The site discussed in this paper is on the Mountain Home Air Force Base, where a drillhole in 1984 indicated that geothermal fluids were present at about 1.8 km depth.
In their study published in Lithosphere this week, James Kessler and colleagues examine the geology of a scientific borehole drilled into the Snake River Plain, Idaho, USA, to investigate the potential for geothermal energy at depth. The site discussed in this paper is on the Mountain Home Air Force Base, where a drillhole in 1984 indicated that geothermal fluids were present at about 1.8 km depth.
With ARRA funding for new energy research and a grant from the International Continental Drilling Program, Kessler and colleagues drilled three 2-km-deep holes in the region. The Snake River Plain is the track of the Yellowstone Hotspot, and consists of rhyolite and basalt. Volcanic rocks near Yellowstone are quite young, whereas at Mountain Home, Idaho, the rocks are three to five million years old. Despite the abundant evidence for heat, the Snake River Plain does not produce geothermal energy due to a cool water aquifer present in the upper 500 m of the rocks.
The work reported in this paper is on the Mountain Home site, where waters of about 150 °C were encounter at 1745 m depth. Kessler and colleagues report on the geology of the basaltic rocks of the borehole, including determining the distribution of the basalts, the presence of faults and fractures at depth, and evidence for older hydrothermal interactions.
Read more at Geological Society of America
Image: Examples of fractures and vesicles in the MH-2 core. (Credits: Kessler via Geological Society of America)
