Spherulitic omphacite in pseudotachylytes: Microstructures related to fast crystal growth from seismic melt at eclogite-facies conditions

Omphacite microstructures are commonly discussed as result of deformational stresses due to a tectonic forcing. Here, we hypothesize that thermal stress during growth also can provide a feasible explanation for this melt-grown omphacite followed with partial recovery under static conditions. The observation does not exclude repeated stress loading of the shear veins in general, but suggest that only the latest seismic event is preserved in the studied samples as fine-grained texture of the spherulites. Moreover, anti-phase domain sizes constrain that the rock must be uplifted rather shortly after the seismic event.