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Fluid-inclusion technique for determining maximum temperature in calcite and its comparison to the vitrinite reflectance geothermometer

C.E. Barker·R.H. Goldstein
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Abstract

Theory, laboratory experiments, and empirical observation suggest that many aqueous fluid inclusions in calcite reequilibrate during overheating, and therefore some homogenization temperatures ( T h ) record a temperature close to the maximum reached by the rock. This characteristic suggests that aqueous fluid inclusions in calcite can be used to establish maximum temperature ( T peak ). To test this hypothesis, we have compiled fluid inclusion T peak , mean random vitrinite reflectance ( R m ), and present-day T peak from 46 diverse geologic systems that have been at T peak from 10 4 to 10 6 yr. Present T peak ranged from 65 to 345 °C, T h modes and means ranged from 59 to 350 °C, and R m data ranged from 0.4% to 4.6%, spanning the temperature and thermal maturity range associated with burial diagenesis, hydrothermal alteration, and low-grade metamorphism.

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C.E. Barker, R.H. Goldstein. 1990. Fluid-inclusion technique for determining maximum temperature in calcite and its comparison to the vitrinite reflectance geothermometer. https://doi.org/10.1130/0091-7613(1990)018%3C1003%3Afitfdm%3E2.3.co%3B2

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