Metamorphic history of the southern Menderes massif, western Turkey


Whitney D., Bozkurt E.

GEOLOGICAL SOCIETY OF AMERICA BULLETIN, cilt.114, ss.829-838, 2002 (SCI İndekslerine Giren Dergi) identifier

Özet

Metamorphic mineral compositions and textures are integrated with microstructures to test tectonic models for the construction and exhumation of a mid-crustal terrane in western Turkey. The southern Menderes massif, part of the Alpine orogen, is composed of a tilted sequence of metasedimentary rocks that structurally overlies orthogneiss. Garnet-biotite equilibria for schists collected along north-south traverses consistently indicate temperatures of 430 degreesC for the southernmost, structurally highest garnet-bearing rocks, similar to500 degreesC for structurally intermediate rocks, and similar to550 degreesC for the structurally deepest rocks near the contact with the orthogneiss. There are no detectable discontinuities in metamorphic grade from north to south within the schist unit, or between the schist and overlying lower-grade and underlying higher-grade rocks. Pressure estimates are less certain; geobarometric results for the schists yield P approximate to 8 kbar, but mineral assemblages and structural data are consistent with lower pressures (less than or equal to6 kbar).