A Laboratory Exercise on Cratering in a Geology Course for Non-Science Majors

Abstract

Impact cratering is as important a surface process on rocky planetary bodies as are the actions of wind, water, and ice. A simple laboratory exercise in producing very low-velocity impact craters in sand boxes helps students visualize a part of the cratering process in a freshman course for non-science majors. Students measure the diameter and heights of craters, calculate crater volume and the kinetic energy (KE) of impacts, plot several variables in a log-normal space, and determine the relationship between crater diameter and KE. Standard errors in measurements and deviation of experimental data from a theoretical formulation provide students with a sense of relative robustness of data, relative strengths of interpretation, and limitations of scaling up from laboratory experiments to mimic natural phenomena.