The timing of high-temperature conditions and ductile shearing in the footwall of the Naxos extensional fault system, Aegean Sea, Greece

摘要: Abstract We present eight Rb-Sr multi-mineral isochron ages showing that high-temperature metamorphic conditions and partial melting during top-to-the-NNE extensional shearing in the footwall of Naxos fault system (i.e. core complex) lasted until about 14–12 Ma. One migmatite sample yielded an age 14.34 ± 0.2 Ma (2σ uncertainty) for crystallization migmatization-related melt pockets. Four pegmatite samples, which are part associated with their host rocks, provided overlapping ranging from 13.81 to 12.23 Ma (age range includes 2σ uncertainty). Additional three samples amphibolite-facies schist supplied around 14 Ma. Samples fluid- and/or deformation-assisted white mica biotite reworking gave mineral apparent 11.1 ± 2.7, 10.16 ± 0.24, 9.7 ± 0.7 9.6 ± 0.15 Ma. These interpreted be late stages under greenschist-facies conditions. Together published U-Pb zircon migmatite, S- I-type granite crystallization, data indicate presence at least 7 Ma (from ~18 ~11 Ma). This demonstrates high temperatures crustal resulting aiding deformation was a long-lived not transient event. conclude melt-assisted facilitated large-scale displacement on by drastically weakening extending crust long periods time.