Physicochemical basis of the Na-K-Ca geothermometer [electronic resource]
Geothermal Legacy.
Saved in:
| Online Access: |
Online Access |
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| Corporate Author: | |
| Format: | Government Document Electronic eBook |
| Language: | English |
| Published: |
Los Alamos, N.M. : Oak Ridge, Tenn. :
Los Alamos National Laboratory ; distributed by the Office of Scientific and Technical Information, U.S. Dept. of Energy,
1986.
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| Subjects: |
| Summary: | Geothermal Legacy. |
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| Abstract: | Regular changes in solution composition were observed experimentally during granite reaction with dilute NaCl (+CaCl₂) solutions; these changes closely follow the empirical Na-K-Ca geothermometer relationship. Initial minerals forming the granite (quartz, plagioclase, K-feldspar, and biotite) were etched by the reactions. Alteration phases formed include calcium-zeolite at <300°C, feldspar overgrowths at >300°C, and minor amounts of clay and calcsilicate at all temperatures. Amphibole overgrowths were also found at 340°C. Quartz is near saturation in all experiments, and preliminary calculations of aqueous species distributions and mineral affinities indicate that the solutions achieve super-saturation with feldspars as the temperature increase. A consistent variation attributable to pH differences was observed in the empirical geothermometer relationship for all experimental data. At 340°C, the experimental solutions appear to have deviated slightly from the empirical Na-K-Ca relationship. Such deviations may also be found in natural systems that attain such temperatures. |
| Item Description: | Published through the Information Bridge: DOE Scientific and Technical Information. 08/01/1986. "la-10806-ms" "DE87000805" Janecky, D.R.; Bayhurst, G.K.; Charles, R.W.; Benjamin, T.M. |
| Physical Description: | Pages: 11 : digital, PDF file. |