HR: 0800h
AN: MR11B-0937    [Abstracts]
TI: Earth Science Research at the Homestake Deep Underground Science and Engineering Laboratory
AU: * Roggenthen, W
EM: william.roggenthen@sdsmt.edu
AF: S. D. School of Mines-Tech., Dept. Geol/Geol. Eng., Rapid City, SD 57701 United States
AU: Wang, J
EM: jswang@lbl.gov
AF: Lawrence Berkeley National Laboratory, Earth Sciences Division, Berkeley, CA 94720 United States
AB: The Homestake Mine in South Dakota ceased gold production in 2002 and was sealed for entry in 2003. The announcement of mine closure triggered the revival of a national initiative to establish a deep underground facility, currently known as the Deep Underground Science and Engineering Laboratory (DUSEL). The National Science Foundation announced that solicitations were to be issued in 2004 and 2005, with the first one (known as S-1) issued in June, 2004. The focus of S-1 is on site non-specific technical requirements to define the scientific program at DUSEL. Earth scientists and physicists participated in an S-1 workshop at Berkeley in August, 2004. This abstract presents the prospects of the Homestake Mine to accommodate the earth science scientific programs defined at the S-1 workshop. The Homestake Mine has hundreds of kilometers of drifts over fifty levels accessible (upon mine reopening) for water evaluation, seepage quantification, seismic monitoring, geophysical imaging, geological mapping, mineral sampling, ecology and geo-microbiology. The extensive network of drifts, ramps, and vertical shafts allows installation of 10-kilometer-scale seismograph and electromagnetic networks. Ramps connecting different levels, typically separated by 150 ft, could be instrumented for flow and transport studies, prior to implementation of coupled thermal-hydro-chemical-mechanical-biological processes testing. Numerous large rooms are available for ecological and introduced-material evaluations. Ideas for installing instruments in cubic kilometers of rock mass can be realized over multiple levels. Environmental assessment, petroleum recovery, carbon sequestration were among the applications discussed in the S-1 workshop. If the Homestake Mine can be expediently reopened, earth scientists are ready to perform important tests with a phased approach. The drifts and ramps directly below the large open pit could be the first area for shallow testing. The 4,850 ft level is the next target area, which has a large lateral extent. Geophysical sensor stations could be installed at this level, together with stations along two main shafts accessing this level, and one winze below. After dewatering, rock mechanics and geotechnical engineering investigators could actively participate in room siting and excavation, at depths up to 8,000 ft. Geochemistry and geo-microbiology scientists would prefer additional drilling in deep zones beyond the mining and flooding perturbations. Additional earth science programs are being developed for the Homestake Mine, utilizing multiple levels and shafts. Many physics experiments require a site "as deep as possible" and special conditions to reduce background and cosmic rays. The Homestake Mine offers a very deep site and a vast amount of data and knowledge associated with its 125 years of mining operation. The cores from exploratory drilling into a mechanical strong unit, the Yates Formation, are available for scientific and engineering evaluations. A team from many institutions is being formed by Kevin Lesko, a neutrino scientist with experience in detecting neutrino oscillations with deep detectors in Canada and Japan. It is time for the United States to establish a DUSEL deep and large enough for next-generation physics and earth science long-term experiments. The Homestake Mine has these necessary attributes. The collaboration welcomes participation and contribution from scientists and engineers in the physics and earth science community for multi-disciplinary research during and after the restoration and conversion of the Homestake Mine.
DE: 1899 General or miscellaneous
DE: 0399 General or miscellaneous
DE: 0400 Biogeosciences
SC: Mineral and Rock Physics [MR]
MN: 2004 AGU Fall Meeting