Abstract
Shock pressure distribution in the basement rocks of the Chicxulub impact crater was evaluated based on cathodoluminescence spectroscopy of quartz in order to constrain the formation processes of large impact craters. Estimated shock pressures of granitic rocks in the drilling core samples recovered by the IODP 364 expedition was in the range of 15-20 GPa. Shock pressure attenuation in the Chicxulub crater is small, however, the pressures in depth below seafloor of 1100-1200 m is slightly large. This suggests a convolute mixing process of the basement rocks during cratering.