Abstract
High-Mg chloritoid (XMg ¼ 0� 40^0� 47) and relatively high-Mg staurolite (XMg ¼ 0� 25^0� 28) coexisting with kyanite and garnet were identified in a mica^garnet-rich rock associated with very high-pressure eclogites in the Bughea Complex of the Leaota Massif (South Carpathians). Major and trace element geochemical data for both fresh eclogites and associated rocks which represent a metasomatic or retrograde alteration rind of the eclogites, indicate a pelitic precursor. Magnesian chloritoid was found as inclusions in garnet as part of a chloritoid^kyanite^garnet assemblage which is indicative of high-pressure conditions. The host garnet shows a typically prograde chemical zoning pattern.The chloritoid-bearing assemblage is confined to the inner part of the garnet porphyroblasts, whereas the matrix assemblage in equilibrium with Mg-rich garnet rims has exceeded the thermal stability limit of chloritoid. Pressure^temperature pseudosections for simplified compositions approaching the rock bulk-chemistry show a high-pressure field for the identified chloritoid-bearing assemblage in good agreement with pressure^temperature estimates in the CFMASH and KCFMASH chemical subsystems using analysed mineral compositions. The derived pressure^temperature path is clockwise, indicating overprinting during exhumation from 1� 8G Pa and 5808 Ct o 1� 15 GPa and 6208C, at a water activity approaching aH2O ¼1.These conditions were attained � �
Published Version
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