The compositional zoning of garnet in eclogite from western segment of Altyn Tagh, northwestern China and its dynamic significance
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The eclogites from the Altyn Tagh, northwestern China have been subjected to mediumtemperature and high-pressure metamorphism, and then overprinted by the amphibolite to granulite facies retrograde metamorphism. A complex compositional zoning was well preserved in the garnet porphyroblast formed during the metamorphism of eclogite facies. This zoning recordedP-T path of multistage metamorphism, and an early retrogressive process with features of decreasing pressure and increasing temperature. This evidences a short residence time for the eclogite at peak metamorphism and early retrogression, and thus rapid tectonic uplift history.
Keywordseclogite garnet growth zoning P-T path exhumation rate Altyn Tagh
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