Distribution of NaAlSi/sub 3/O/sub 8/ between coexisting microcline and plagioclase and its effect on geothermometric calculations

Journal Article · Sat Jan 01 04:00:00 EST 1977 · Am. Mineral.; (United States)

OSTI ID:6835281

Whitney, J A; Stormer, Jr, J C

The partitioning of NaAlSi/sub 3/O/sub 8/ between coexisting microcline and plagioclase solid-solutions is modeled using published Margules parameters for microcline-low albite solid-solutions. Variations in the structural state of the alkali feldspar may shift the temperature calculated from coexisting feldspar pairs by as much as 100/sup 0/C. The magnitude of this shift varies with the compositions of the coexisting feldspar, but will generally be less than 100/sup 0/C. In nature, the effect of ordering would be less for primary orthoclase, and would not be significant if the feldspar originally equilibrated in the disordered state.

• Research Organization: Univ. of Georgia, Athens
• OSTI ID: 6835281
• Journal Information: Am. Mineral.; (United States), Journal Name: Am. Mineral.; (United States) Vol. 62:7/8; ISSN AMMIA
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
152004* -- Geothermal Data & Theory-- Isotope & Trace Element Studies
58 GEOSCIENCES
580400 -- Geochemistry-- (-1989)
ALKALI METAL COMPOUNDS
ALUMINIUM COMPOUNDS
ANORTHOSITES
CRYSTAL STRUCTURE
DISPERSIONS
DISTRIBUTION
FELDSPARS
GEOTHERMOMETERS
GEOTHERMOMETRY
IGNEOUS ROCKS
MEASURING INSTRUMENTS
MINERALS
MIXTURES
OXYGEN COMPOUNDS
PARTITION
ROCKS
SILICATES
SILICON COMPOUNDS
SODIUM COMPOUNDS
SOLID SOLUTIONS
SOLUTIONS
TEMPERATURE MEASUREMENT
THERMOMETERS