Metamorphic evolution of eclogite and associated garnet-mica schist in thehigh-pressure metamorphic Maksyutov complex, Ural, Russia

Metasedimentary garnet-mica schists are interlayered with metabasic garnet- omphacite schists and enclose eclogite boudins in the high-pressure metamor phic Maksyutov complex in the Southern Urals, Russia. These three rock type s were investigated in one outcrop and compared chemographically and thermo barometrically. The Fe/Mg distributions between garnet rim-omphacite and ga rnet rim-phengite pairs indicate different equilibration temperatures for t he three samples, with the lowest temperature (500 degrees C, >1.5 GPa) for the eclogite boudin, an intermediate temperature (630 degrees C, >1.7 GPa) for the foliated eclogite and the highest temperature (650 degrees C, >1.7 GPa) for the garnet-mica schist. The garnets in garnet-mica schist enclose abundant chloritoid relies and the Fe/Mg distribution between chloritoid a nd garnet records an earlier high-temperature stage (650 degrees C, >2.0 GP a) before the garnet rim-phengite temperatures were reached. Together with some minimum- and maximum-pressure estimates three different prograde press ure-temperature paths and a common retrograde metamorphic evolution are int erpreted from the chemographic and thermobarometric data. The different ear ly metamorphic evolutions and conditions confirm the variability of protoli ths, which are also indicated by different U/Pb zircon and rutile ages.