Speaker: Dr. Sonia Tikoo-Schantz; Assistant Professor, Rutgers University
Impact cratering is a ubiquitous geological process that modifies the surfaces of planetary bodies across our solar system. Impacts expose rocks to powerful shock waves and heat. Post-impact cooling of craters may drive hydrothermal systems that can persist for hundreds of thousands of years. Because heat, shock, and hydrothermalism are all capable of resetting rock magnetization, the field of paleomagnetism may be used as a powerful tool to investigate the physical conditions associated with impact events. Here, we discuss how paleomagnetism was used to constrain temperatures and structural changes experienced by rocks during crater formation at the Slate Islands impact structure (Canada). We also discuss how paleomagnetism is now being used to investigate the duration of post-impact hydrothermal activity at the Chicxulub crater, Mexico. Magnetic methods applied to impacts may be extended to assess any geological setting involving pressures, elevated temperatures, and hydrothermal activity, such as the Earth’s crust, mid-ocean ridges, and meteorite parent planetesimals.