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Ternary feldspar experiments and thermodynamic models
Description
A data set that has been manually transcribed from Table 5 of Elkins and Grove's Ternary feldspar experiments and thermodynamic models.
Usage
feldspar
Format
A data frame of 40 rows and 7 columns:
- Experiment
The ID of the experiment
- Feldspar
Coexisting feldspars, Alkali or Plagioclase
- Or
Proportion of orthoclase
- An
Proportion of anorthite
- Ab
Proportion of albite
- Temperature
Temperature of the reaction (degrees centigrade)
- Pressure
Pressure of the reaction (bars)
Abstract
This paper reports the results of 20 experiments in which mixes of two or three feldspars were reacted to produce coexisting plagioclase feldspar (PF) and alkali feldspar (AF). Starting materials with similar bulk compositions were prepared using different combinations of two and three minerals, and experiments were designed to produce similar AF and PF minerals in the experimental products from different starting binary and ternary compositions. The coexisting AF and PF compositions produced as products define compositional fields that are elongate parallel to the ternary solvus. In 11 experiments reaction was sufficient to product fields of coexisting AF and PF, or AF, PF, and melt with a bulk composition close to that of the starting mixture. In six experiments significant reaction occurred in the form of reaction rim overgrowths on seeds of the starting materials. Three experiments produced AF, PF, and melt from a natural granite starting material. A two-feldspar thermometer is presented in which temperature is constrained by equilibria among all three components - Albite, Orthoclase, and Anorthite - in coexisting ternary feldspars.
Source
Elkins LT, Grove TL. Ternary feldspar experiments and thermodynamic models. American Mineralogist. 1990;75(5-6):544-59.