Pressure-temperature path of metapelites from the Algyő-Ferencszállás area, SE Hungary: thermobarometric constraints from coexisting mineral assemblages and garnet zoning

The polymetamorphic evolution path of metapelites characteristic of the Algyo-Ferencszallas Metamorphic Complex of the Bekes-Codru Unit (SE Hungary) is presented on the basis of microstructural and mineral paragenetic features, mineral chemical data and geothermobarometric calculations. The first (Variscan?) metamorphic event recorded by the Ca-rich part of zoned garnets from the Ferencszallas area is poorly defined, yielding conditions of 520-560 oC and 820-1010 MPa. This event was followed by a new tectonometamorphic phase that began with the formation of garnet, kyanite, muscovite, plagioclase and biotite. This younger (Alpine) event is marked by the decomposition of staurolite and biotite, and an increase in temperature and pressure. Peak metamorphic conditions reached c. 650 oC and 900 MPa in the Ferencszallas and Ujszentivan areas. This P-T peak was followed by continuous decrease in temperature and pressure to c. 500-560 oC and 400-530 MPa. The P-T path calculations from the progressively zoned gar...