Modelling Exploding Rocks
by
Mark McGuinness
Victoria University of Wellington
Coauthors: A.C. Fowler, B. Scheu, W. Lee

We present and solve a mathematical model of recent experimental work, in which a vertical column of rock under large pressure is suddenly depressurised, so that it explodes, in a sequence of horizontal fractures that forms from the top down. The resulting blocks are lifted off and ejected. This experiment provides a framework for understanding the way in which catastrophic explosion can occur, and is motivated by the corresponding phenomenon of magmatic explosion during Vulcanian eruptions. We summarise a theoretical model built to describe these results, and show that it is capable of describing both the primary sequence of fracturing, and the secondary intra-block fracturing.

Date received: November 22, 2009