Fission track dating of faulting events accommodating plastic deformation of biotites

We performed fission track (FT) analyses to constrain the timing of fault slip events associated with plastic deformation of biotite grains formed at high temperature, higher than 200–300°C. Apatite FT ages of 49.6–16.7 Ma were obtained from Late Cretaceous granites near the fault, with younger ages near a basaltic dike that intruded at ~19 Ma. By comparing the distribution of apatite FT ages using forward thermal and FT annealing calculations,...