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Evolution of mineral assemblages and textures from sediment through hornfels in the Salton Sea Geothermal Field: Direct crystallization of phyllosilicates in a hydrothermal-metamorphic system

Published online by Cambridge University Press:  09 July 2018

G. Giorgetti ,
M. P. Mata  and
D. R. Peacor
G. Giorgetti*
Affiliation:
Dipartimento di Scienze della Terra, Università degli Studi di Siena, Via Laterina 8, 53100 Siena, Italy Department of Geological Sciences, The University of Michigan, Ann Arbor, MI 48109-1063, USA
M. P. Mata
Affiliation:
Departamento de Geología, Facultad de Ciencias del Mar, Universidad de Cadiz, Campus Río San Pedro, 11510 Puerto Real (Cadiz), Spain
D. R. Peacor
Affiliation:
Department of Geological Sciences, The University of Michigan, Ann Arbor, MI 48109-1063, USA
*
*E-mail: [email protected]
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Abstract

Microanalytical data on Plio-Pleistocene sediments from a Salton Sea Geothermal Field well define the evolution of textures and mineral assemblages from sediment to metamorphic rock in an open hydrothermal system.

At shallow depths detrital grains occur within a fine-grained matrix of I-S and illite. As depth and temperature increase, grains lose their detrital characteristics; they subsequently form a continuous intergrown array of irregular domains, with phyllosilicates occupying the progressively decreasing pore space.

Illite and chlorite are authigenic phyllosilicates down to 2500 m, where biotite occurs. Authigenic phyllosilicates occur as subhedral crystals (200 –600 Å thick). Alkali feldspar has end-member compositions, implying exchange of alkalis with convected fluids. Changes in texture imply dissolution of detrital phases and neocrystallization of authigenic phyllosilicates directly from pore fluids. Changes with depth are not time-dependent for phyllosilicates: they formed simultaneously at all depths as a result of a single hydrothermal event in an open system.

Keywords

clay mineralsSalton Sea Geothermal Fieldneocrystallizationshaleselectron microscopy
Type
Research Article
Information
Clay Minerals , Volume 38 , Issue 1 , March 2003 , pp. 113 - 126
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 2003

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References

Ahn, J.H. & Peacor, D.R. (1985) Transmission electron microscopy study of diagenetic chlorite in Gulf coast argillaceous sediments. Clays and Clay Minerals, 33, 228–236.CrossRefGoogle Scholar
Bauluz, B., Peacor, D.R. & Ylagan, R.F. (2002) Transmission electron microscopy study of smectite illitization during hydrothermal alteration of a rhyolitic hyaloclastite from Ponza, Italy. Clays and Clay Minerals, 50, 157–173.CrossRefGoogle Scholar
Cho, M., Liou, J.G. & Bird, D.K. (1988) Prograde phase relations in the State 2-14 well metasandstones, Salton Sea Geothermal Field, California. Journal of Geophysical Research, 93, 13081– 13103.Google Scholar
Craig, H. (1966) Isotopic composition and origin of the Red Sea and Salton Sea geothermal brines. Science, 154, 1544–1548.Google ScholarPubMed
Deer, W.A., Howie, R.A. & Zussman, J. (2001) Rockforming Minerals, Framework Silicates, Feldspars. The Geological Society, London, 972 pp.Google Scholar
Deubener, J., Sternitzke, M. & Müller, G. (1991) Feldspars MAlSi3O8 (M = H, Li,Ag) synthesized by low-temperature ion exchange. American Mineralogist, 76, 1620–1627.Google Scholar
Donaghe, L.L. & Peacor, D.R. (1987) Textural and mineralogic transitions in SSSDP argillaceous sediments. EOS, Transactions of American Geophysical Union, 68, 454.Google Scholar
Giorgetti, G., Mata, P. & Peacor, D.R. (2000) TEM study of the mechanism of transformation of detrital kaolinite and muscovite to illite/smectite in sediments of the Salton Sea Geothermal Field. European Journal of Mineralogy, 12, 923–934.Google Scholar
Helgeson, H.C. (1967) Solution chemistry and metamorphism. Pp. 362–404 in: Researc hes in Geochemistry, II (Abelson, P.H., editor). New York.Google Scholar
Helgeson, H.C. (1968) Geological and thermodynamic characteristics of the Salton Sea Geothermal System. American Journal of Sciences, 266, 129–166.CrossRefGoogle Scholar
Herzig, C.T. & Mehegan, J.M. (1988) Litostratigraphy of the state 2-14 borehole: Salton Sea scientific drilling project. Journal of Geophysical Research, 93, 969–980.Google Scholar
Hower, J., Eslinger, E.V., Hower, M.E. & Perry, E.A. (1976) Mechanism of burial metamorphism of argillaceous sediments: 1. Mineralogical and chemical evidence. Geological Society of America Bulletin, 87, 725–737.Google Scholar
Kim, J.W. & Peacor, D.R. (2002) Crystal-size distributions of clays during episodic diagenesis: The Salton Sea geothermal system. Clays and Clay Minerals, 50, 371–380.CrossRefGoogle Scholar
Lee, H.J., Peacor, D.R., Lewis, D.D. & Wintsch, R.P. (1985) Chlorite-illite/muscovite interlayered and interstratif ied crystal: a TEM/STEM study. Contributions to Mineralogy and Petrology, 88, 372–385.CrossRefGoogle Scholar
McConnell, J.D.C. (1974) Analysis of the time-temperature- tansformation behaviour of the plagioclase feldspars. Pp 478–490 in: The Feldspars (MacKenzie, W.S. & Zussman, J., editors). Manchester University Press, Manchester, UK.Google Scholar
McDowell, S.D. (1986) Composition and structural state of coexisting feldspar, Salton Sea geothermal field. Mineralogical Magazine, 50,75 –84.Google Scholar
McDowell, S.D. & Elders, W.A. (1980) Authigenic layer silicate minerals in borehole Elmore 1, Salton Sea Geothermal Field, California, USA. Contributions to Mineralogy and Petrology, 74, 293–310.CrossRefGoogle Scholar
Mehegan, J.M., Herzig, C.T. & Sullivan, R.M. (1986) Visual core descriptions, Salton Sea Scientific Drilling Project, Californi a State 2-14 well. Institute of Geophysics and Planetary Physics, University of California, Riverside.Google Scholar
Merriam, R. & Bandy, O.L. (1965) Source of upper Cenozoic sediments in Colorado delta region. Journal of Sedimentary Petrology, 35, 911–916.Google Scholar
Morton, J.P. (1985) Rb-Sr evidence for punctuated illite/ smectite diagenesis in the Oligocene Frio Formation, Texas Gulf Coast. Geological Society of America Bulletin, 96, 114–122.2.0.CO;2>CrossRefGoogle Scholar
Muffler, L.P.J. & Doe, B.R. (1968) Composition and mean age of detritus of the Colorado River delta in the Salton Trough, southeastern California. Journal of Sedimentary Petrology, 38, 384–399.Google Scholar
Muffler, L.P.J. & White, D.E. (1969) Active metamorphism of Upper Cenozoic sediments in the Salton Sea Geothermal Field and the Salton Trough, southeastern California. Geological Society of America Bulletin, 80, 157–182.Google Scholar
Ohr, M., Halliday, A.N. & Peacor, D.R. (1991) Sr and Nd isotopic evidence for punctuated clay diagenesis, Texas gulf Coast. Earth and Planetary Science Letters, 105, 110–126.CrossRefGoogle Scholar
Sass, J.H., Priest, S.S., Duda, L.E., Carson, C.C., Hendricks, J.D. & Robinson, L.C. (1988) Thermal regime of the state 2-14 well, Salton Sea Scientific Drilling Project. Journal of Geophysical Research, 93, 12995–13004.CrossRefGoogle Scholar
Smith, J.V. (1983) Phase equilibria of plagioclase. Pp. 223– 241 in. Feldspar Mineralogy (Ribbe, P.H., editor). Reviews in Mineralogy, 2. Mineralogical Society of America, Washington, D.C.Google Scholar
Tillick, D.A., Peacor, D.R. & Mauk, J.L. (2001) Genesis of dioctahedral phyllosilicates during hydrothermal alteration of volcanic rocks: I. The Golden Cross epithermal ore deposit, New Zealand. Clays and Clay Minerals, 49, 126–140.CrossRefGoogle Scholar
Williams, A.E. & McKibben, M.A. (1989) A brine interface in the Salton Sea Geothermal System, California: Fluid geochemical and isotopic characteristics. Geochimica et Cosmochimica Acta, 53, 1905–1920.CrossRefGoogle Scholar
Yan, Y., Tillick, D.A., Peacor, D.R. & Simmons, S.F. (2001) Genesis of dioctahedral phyllosilicates during hydrothermal alteration of volcanic rocks: II. The Broadlands hydrothermal system, New Zealand. Clays and Clay Minerals, 49, 141–155.CrossRefGoogle Scholar
Yau, Y.C., Peacor, D.R. & Essene, E.J. (1987a) Authigenic anatase and titanite in shales from the Salton Sea Geothermal Field, California. Neues Jahrbuch für Mineralogie Monatshefte, 441–452.Google Scholar
Yau, Y.C., Peacor, D.R. & McDowell, S.D. (1987b) Smectite-to-illite reactions in Salton Sea shales: a transmission and analytical electron microscopy study. Journal of Sedimentary Petrology, 57, 335– 342.Google Scholar
Yau, Y.C., Peacor, D.R., Beane, R.E., Essene, E.J. & McDowell, S.D. (1988) Microstructures, formation mechanism, and depth-zoning of phyllosilicates in geothermally altered shales, Salton Sea, California. Clays and Clay Minerals, 36, 1–10.Google Scholar