First Results from HOTSPOT: The Snake River Plain Scientific Drilling Project, Idaho, U.S.A.

摘要

HOTSPOT is an international collaborative effort tounderstand the volcanic history of the Snake RiverPlain (SRP). The SRP overlies a thermal anomaly, theYellowstone-Snake River hotspot, that is thought to representa deep-seated mantle plume under North America. Theprimary goal of this project is to document the volcanic andstratigraphic history of the SRP, which represents the surfaceexpression of this hotspot, and to understand howit affected the evolution of continental crust and mantle.An additional goal is to evaluate the geothermal potential ofsouthern Idaho.Project HOTSPOT has completed three drill holes.(1) The Kimama site is located along the central volcanicaxis of the SRP; our goal here was to sample a long-termrecord 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-temperaturerhyolite volcanism associated with the underlying plume.This site was chosen to form a nominally continuous recordof volcanism when paired with the Kimama site. (3) The Mountain Home site is located in the western plain; our goalhere was to sample the Pliocene-Pleistocene transition inlake sediments at this site and to sample older basalts thatunderlie the sediments.We report here on our initial results for each site, and onsome of the geophysical logging studies carried out as partof this project.doi:href="http://dx.doi.org/10.2204/iodp.sd.15.06.2013" target="_blank">10.2204/iodp.sd.15.06.2013