Geochemistry of quartz and calcite veins in a paleoaccretionary complex

摘要

Stable isotope (O, C, H) and trace element geochemistry of quartz and calcite veins, located in a subducted and subsequently exhumed sedimentary series [the high pressure-low temperature (HP-LT) metamorphic Phyllite-Quartzite (PQ) unit of Crete] were used to put constraints on the origin and composition of fluids, and the scale and mechanisms of fluid movement in deep levels of accretionary complexes. Results indicate that veins were formed at different stages of the tectonic evolution, basically from progressively heated connate waters/formational brines to which metamorphic fluids were admixed from dehydration reactions.