Diffraction measurements with synchrotron radiation on superimposed deformed composite of quartzite and dunite

A composite specimen (cylinder) consisting one half each of dunite and quartzite was superimposed (shock) deformed (16-34 GPa). Intracrystalline residual strain was determined from diffraction pattern, obtained using synchrotron radiation at beamline ROBL (ESRF Grenoble). Considerable differences in residual microstrain were determined as the interface is approached. Moreover, the tendencies in size evolution of scattering crystallites were evaluated by diffraction peak shape analysis. The superimposed deformation produced a new microsize structure in dunite, but was only modifying the macrostructure in quartzite, which already exists before the superimposed deformation. Otherwise, the size of scattering crystallites (related to foliation) of quartzite was reduced about six times more than that of dunite (in relation to the newly formed structure).