Abstract: Metamorphic rocks at Milos are known in small outcrops beneath the volcanic formations, as xenoliths in the Traphores volcanic breccia and as pebbles in the Paleochora Quaternary deposits. These rocks seem to belong to three different metamorphic units which probably have intricate relationships in the basement: — the “eclogites unit” shows garnetjadeite or garnet-omphacite primary associations, with apparently late crystallization of lawsonite phenoblasts an recrystallization features at relatively low temperatures; — the “glaucophane schist unit” exhibits Jadeite+quartz or glaucophane+lawsonite primary mineralogy; — the “greenschist facies unit” shows low-pressure main assemblages, most generally developed after high-pressure events. The two former units involve tholeiitic meta-igneous rocks, having been spilitized before metamorphism; they generally suffered more or less advanced recrystallization features in the low-pressure field of the greenschist facies. The third unit shows only meta-sedimentary rocks, with the sole exception of one single meta-doleritic pebble having calk-alkaline affinities. Petrological and mineralogical studies, based upon 15 bulk-rock compositions and 178 probe-analysed data points, lead to suspect at least 2, perhaps 3, different metamorphic events rather than one single metamorphic evolution, to account for the 3 U distinguished. From the observation of the mineralogical assemblages and their evolution, the former events (“stages 1 and 2”) could be related to rapid subduction of ocean-floor or back-arc basalts, whereas, during the latter event (“stage 3”), the rocks experienced crystallization conditions involving both decreasing pressures and increasing temperatures.

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   |wiki=    Wicri/Terre
   |area=    NissirosV1
   |flux=    Main
   |étape=   Exploration
   |type=    RBID
   |clé=     ISTEX:C82F5AFE7557C0AF18F9AA09F1688334F27BF42F
   |texte=   The high-pressure assemblages at Milos, Greece
}}