Welded Tuff : A pyroclastic rock in which glassy clasts have been fused by the combination of the heat retained by the clasts, the weight of overlying material, and hot gases
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}