A self-sustaining nuclear reaction, made possible when neutrons released by fission of some atoms in a nuclear reactor strike other atoms, causing them to fission as well
Iowa State University, College of Liberal Arts and Sciences, Department of Geological and Atmospheric Sciences, Glossary of Geologic Terms (based on the glossary in Earth: An Introduction to Geologic Change, by S. Judson and S.M. Richardson, Englewood Cliffs, NJ, Prentice Hall, 1995), Iowa, USA 2004. http://www.ge-at.iastate.edu/courses/Geol_100/old_ files/glossary.v2.html, (ND/ Geol - Amer) {111}