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The smectite to corrensite transition: X-ray diffraction results from the MH-2B core, western Snake River Plain, Idaho, USA

Published online by Cambridge University Press:  02 January 2018

Jeff Walker  and
Joseph Wheeler
Jeff Walker*
Affiliation:
Department of Earth Science and Geography, Vassar College, Poughkeepsie, NY 12604, USA
Joseph Wheeler
Affiliation:
Department of Earth Science and Geography, Vassar College, Poughkeepsie, NY 12604, USA
*
*E-mail: jewalker@vassar.edu
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Abstract

The MH-2B borehole, a part of Project HOTSPOT, was drilled to a depth of 1821 m in late Cenozoic basalts, hyaloclastites and interbedded lake sediments, on the Mountain Home Air Force Base in southern Idaho, USA. Drillers encountered hot water (145°C) under artesian pressure at 1745 m in a narrow zone of highly fractured rock associated with a major sub-surface fault. X-ray diffraction (XRD) analysis identified corrensite (with and without smectite) between 1700 and 1800 m, but only smectite above 1700 m and below 1800 m. This corrensite horizon contains a relatively narrow zone of fracturing and hot artesian water near its centre but for the most part occurs in relatively massive basalt flows. No evidence was found for randomly interstratified chlorite-smectite.

Keywords

smectitecorrensiteMH-2B boreholeXRD
Type
Short Note
Information
Clay Minerals , Volume 51 , Issue 4 , September 2016 , pp. 691 - 696
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2016

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Footnotes

†

This work was originally presented during the session ‘The many faces of chlorite’, part of the Euroday 2015 conference held in July 2015, in Edinburgh, UK.

References

Beaufort, D. & Meunier, A. (1994) Saponite, corrensite, and chlorite-saponite mixed layers in the Sancerre-Couy deep drill-hole (France). Clay Minerals, 29, 47–61.CrossRefGoogle Scholar
Breckenridge, R.P., Nielson, D.L., Shervais, J.W. & Wood, T.R. (2012) Exploration and resource assessment at Mountain Home Air Force Base, Idaho, using an integrated team approach. Geothermal Research Council Transactions, 36, 615–619.Google Scholar
Kessler, J.A., Evans, J.P., Shervais, J.W., & Schmitt, D.R. (2013) Characterization of brittle structures in basalt of the western Snake River Plain, Idaho: Implications for fracture connectivity in a potential geothermal reservoir. 125th Annual Meeting Abstracts, (paper #5, session 35), Geological Society of America, Denver, Colorado, USA.Google Scholar
Lachmar, T.E., Freeman, T.G., Wood, T.R., Shervais, J.W. & Nielson, D.L. (2012) Chemistry and thermometry of the geothermal waters from Mountain Home Test Well MH-2B: Preliminary results. Geothermal Research Council Transactions, 36, 689–692.Google Scholar
Moore, D.M. & Reynolds, R.C. (1997) X-ray Diffraction and the Identification and Analysis of Clay Minerals (2nd edition). Oxford University Press, New York, 400 pp.Google Scholar
Nielson, D.L., Delahunty, C. and Shervais, J.W. (2012) Geothermal systems in the Snake River Plain characterized by the Hotspot project. Geothermal Research Council Transactions, 36, 727–730.Google Scholar
Patrier, P., Papapanagiotou, P., Beaufort, D., Traineau, H., Bril, H. & Rojas, J. (1996) Role of permeability versus temperature in the distribution of the fine (>2 \aa) clay fraction in the Chipilapa geothermal system (El Salvador, Central America). Journal of Volcanology and Geothermal Research, 72, 101–120.Google Scholar
Rigault, C., Patrier, P. & Beaufort, D. (2010) Clay minerals related to circulation of near-neutral to weakly acidic fluids in high-energy geothermal systems. Bulletin de Société Géologique de France, 4, 337–347.Google Scholar
Robinson, D. & Santana De Zamora, A. (1999) The smectite to chlorite transition in the Chipilapa Geothermal System, El Salvador. American Mineralogist, 84, 607–619.CrossRefGoogle Scholar
Robinson, D., Schmidt, S.Th. & Santana de Zamora, A. (2002) Reaction pathways and reaction progress for the smectite-to-chlorite transformation: evidence from hydrothermally altered metabasites. Journal of Metamorphic Geology, 20, 167–174.Google Scholar
Shervais, J.W., Shroff, G., Vetter, S.K., Matthews, S., Hanan, B.B. & McGee, J.J. (2002) Origin and evolution of the western Snake River Plain: Implications from stratigraphy, faulting, and the geochemistry of basalt near Mountain Home, Idaho. In. Tectonic and Magmatic Evolution of the Snake River Plain Volcanic Province (W. Bonnichsen, C.M. White & M. McCurry, editors). Idaho Geologic Survey Bulletin, 30, 343–361, Moscow, Idaho USA.Google Scholar
Shervais, J.W., Vetter, S.K., Hanan, B.B. (2006) Layered mafic sill complex beneath the eastern Snake River Plain: evidence from cyclic geochemical variations in basalt. Geology, 34, 365–368.Google Scholar
Shervais, J.W., Evans, I.P., Christiansen, E.J., Schmitt, D.R., Liberty, L.M., Blackwell, D.D., Glen, J.M., Kessler, J.E., Potter, K.E., Jean, M.M. et al. (2011) Hotspot: The Snake River Geothermal Drilling Project - an overview. Geothermal Research Council Transactions, 35, 995–1003.Google Scholar
Wheeler, J. & Walker, J.R. (2013) Clay Mineralization of the MH-2 Core, Snake River Plain, Idaho. 125th Annual Meeting Abstracts, (paper #93, session 247). Geological Society of America, Denver, Colorado, USA.Google Scholar