THE P-T PATH OF GREENSCHIST-FACIES ROCKS FROM THE ISLAND OF KITHNOS (CYCLADES, GREECE)

The island of Kithnos is part of the Attic-Cycladic-Crystalline Comple x (Greece), a polymetamorphic terrane of Alpine age. The succession of Kithnos can be subdivided into an upper tectonic unit consisting of m etagabbroic rocks and a lower unit of intercalated volcanosedimentary rocks: greenschists, albite schists and marbles. Rocks of the lower un it are characterized by greenschist-facies assemblages. Rare mineral r elics of the Eocene high-pressure metamorphism (M1) occur as inclusion s in porphyroblastic albite and epidote. Zonation patterns of actinoli tic amphiboles coexisting with albite, epidote and chlorite indicate a P-T path with increasing pressure and temperature for the Oligocene/M iocene metamorphism (M2). Thus, exhumation of high-pressure rocks can lead to more complicated P-T paths than previously thought.