Mobilization of tin during continental subduction-accretion processes

Major tin (Sn) deposits within the Variscan orogen are closely related to 325–270 Ma postkinematic granites that intruded metamorphic rocks of former precollisional accretionary wedge Gondwana margin. In Erzgebirge (Germany), some these metasedimentary have high Sn contents (locally more than 1000 ppm Sn). We report cassiterite (SnO2) U-Pb ages 395–365 and in prograde biotite rocks. These data demonstrate was already introduced into during accretion metamorphism. Mobilization from sedimentary source fluid loss a subduction-accretion setting represents an important process pre-enrichment upon partial melting may produce Sn-enriched melts. The large-scale mobilization Sn, documented here for first time, highlights possible importance enrichment complexes, thereby explaining spatial distribution major districts orogen.