CHEMICAL AND MINERAL COMPOSITIONS OF METACARBONATE ROCKS UNDER REGIONAL METAMORPHISM CONDITIONS AND GUIDELINES ON ROCK CLASSIFICATION
O.M. Rosen, D. Fettes*, and J. Desmons**
Geological Institute, Russian Academy of Sciences, 7 Pyzhevsky per., Moscow, 119017, Russia * British Geological Survey, Murchison House, West Mains Road, Edinburgh EH9 3LA, Great Britain ** rue de Houdemont, 3, F-54500, Vandoeuvre-lГЁs-Nancy, France
Keywords: Carbonate rocks, metamorphism, systematics of metamorphic rocks
Pages: 351-360
Abstract
Analysis is given to data on the chemical and mineral compositions of Archean-Early Paleozoic metamorphic carbonate rocks of greenschist to granulite facies. A continuous series of pure carbonate to nearly carbonate-free rocks derived from a calcium-enriched sedimentary protolith has been revealed. Several groups of metacarbonate rocks (petrotypes) with statistically significant boundaries between them have been recognized. The boundaries are used as a basis for a systematic scheme of metacarbonate rock nomenclature proposed by the Subcomission on the Systematics of Metamorphic Rocks (SCMR), a branch of the Commission on Systematics in Petrology (CSP) of the International Union of Geological Sciences (IUGS).
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