TY  - JOUR
A1  - Ferrero, Silvio
A1  - Wunder, Bernd
A1  - Walczak, Katarzyna
A1  - Ziemann, Martin Andreas
T1  - Preserved near ultrahigh-pressure melt from continental crust subducted to mantle depths
JF  - Geology
N2  - Remnants of hydrous melt formed at mantle depths have been identified and characterized within high-pressure leucogranulites of the Orlica-Snieznik Dome (Bohemian Massif, central Europe). They occur as nanogranites in garnet formed via partial melting of granitoids during the Variscan orogeny. Melt composition and H2O content have been investigated in situ after experimental re-homogenization of the nanogranites, and are consistent with melts produced experimentally from crustal lithologies at mantle depths. This is the first geochemical study of melt inclusions from natural crustal rocks equilibrated close to the stability field of coesite, shedding light on how continental crust melts during deep subduction. Whereas decompressional melting is commonly invoked for deeply subducted crustal lithologies, melting occurred near or at the metamorphic peak pressure in the Orlica-Snieznik granulites. Melting of deeply subducted crustal rocks significantly modifies the rheology and thus promotes fast exhumation: this process has a critical influence on the geodynamic evolution of subduction-collision orogens as well as crustal differentiation at depth.
Y1  - 2015
U6  - https://doi.org/10.1130/G36534.1
SN  - 0091-7613
SN  - 1943-2682
VL  - 43
IS  - 5
SP  - 447
EP  - 450
PB  - American Institute of Physics
CY  - Boulder
ER  -