Abstract: The deformation of rocks depends on their composition, mechanical properties, and the applied stresses, which vary with pressure, temperature, and depth as they descend into the mantle during subduction. Characterizing the behavior of the rocks and their constituent minerals in response to the applied stresses at pressures and temperatures beyond 20km below the earth’s surface has been extensively carried out over the past few decades, particularly after the advent of the Electron backscattered diffraction (EBSD) technique into geosciences. The EBSD technique allows us to determine the orientations of the crystallographic axes of the target mineral and at the point of interest. The orientation data obtained from the minerals constituting a polymineralic rock sample can be used to estimate several aspects of its past deformation, e.g., temperature, strain regime and intensity, nature (pure- or simple-shear dominated), and, more importantly, the grain-scale mechanism (dislocation- or diffusion-creep). Interestingly, crystallographic orientations of the parent grains can also be inherited by the daughter crystals that replace them. As such, crystallographic inheritance is essentially being used to recover the deformation characteristics of minerals that no longer exist in the rock

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