First Results from HOTSPOT: The Snake River Plain Scientific Drilling Project, Idaho, U.S.A.
1Department of Geology, Utah State University, 4505 Old Main Hill, Logan, UT 84322-4505, USA
2Department of Physics, CCIS 3-091, University of Alberta, Edmonton, Alberta, T6G 2E1, Canada
3DOSECC, Inc., 2075 Pioneer Road, Suite B, Salt Lake City, UT 84104-4231, USA
4Department of Geological Sciences, Brigham Young University, Provo, UT 84602, USA
5U.S. Geological Survey, Central Mineral and Environmental Resources Science Center, Box 25046, MS-973, Denver Federal Center, Denver, CO 80225, USA
6Center for Geophysical Investigation of the Shallow Subsurface, Boise State University, 1910 University Drive, Boise, ID 83725-1536, USA
7Huffington Department of Earth Sciences, Southern Methodist University, P.O. Box 750395, Dallas, TX 75275-0395, USA
8U.S. Geological Survey, 345 Middlefield Road, Menlo Park, CA 94025-3591, USA
9Department of Earth and Ocean Sciences, University of South Carolina, Columbia, South Carolina, 29208, USA
Abstract. HOTSPOT is an international collaborative effort to understand the volcanic history of the Snake River Plain (SRP). The SRP overlies a thermal anomaly, the Yellowstone-Snake River hotspot, that is thought to represent a deep-seated mantle plume under North America. The primary goal of this project is to document the volcanic and stratigraphic history of the SRP, which represents the surface expression of this hotspot, and to understand how it affected the evolution of continental crust and mantle. An additional goal is to evaluate the geothermal potential of southern Idaho.
Project HOTSPOT has completed three drill holes. (1) The Kimama site is located along the central volcanic axis of the SRP; our goal here was to sample a long-term record of basaltic volcanism in the wake of the SRP hotspot. (2) The Kimberly site is located near the margin of the plain; our goal here was to sample a record of high-temperature rhyolite volcanism associated with the underlying plume. This site was chosen to form a nominally continuous record of volcanism when paired with the Kimama site. (3) The Mountain Home site is located in the western plain; our goal here was to sample the Pliocene-Pleistocene transition in lake sediments at this site and to sample older basalts that underlie the sediments.
We report here on our initial results for each site, and on some of the geophysical logging studies carried out as part of this project.
Shervais, J. W., Schmitt, D. R., Nielson, D., Evans, J. P., Christiansen, E. H., Morgan, L., Pat Shanks, W. C., Prokopenko, A. A., Lachmar, T., Liberty, L. M., Blackwell, D. D., Glen, J. M., Champion, L. D., Potter, K. E., and Kessler, J. A.: First Results from HOTSPOT: The Snake River Plain Scientific Drilling Project, Idaho, U.S.A., Sci. Dril., 15, 36-45, doi:10.2204/iodp.sd.15.06.2013, 2013.