Experimental craters formed by single and multiple buried explosions and implications for volcanic craters with emphasis on maars

Craters at many volcanoes, including most maars, are formed by multiple subsurface explosions. Experiments compared the crater formed by a single large, buried explosion, with craters formed by multiple explosions with the same cumulative energy. Explosive charges were detonated in pads composed of layered aggregates, in three configurations: (1) a single large charge buried near its optimal crater excavation depth; (2) three charges, each with 1/3 the energy of the first one, buried at approximately the same depth with respect to the original pad surface; (3) the same three charges buried successively deeper. Final crater size in the multiple explosion cases is not a good indicator of the energy of individual explosions. However, crater morphology, and ejecta volume and distribution can be good indicators of explosion energy and depth. These results directly impact the estimate of the energy released by past maar eruptions and future hazard assessments. Citation: Valentine, G. A., J. D. L. White, P.-S. Ross, J. Amin, J. Taddeucci, I. Sonder, and P. J. Johnson (2012), Experimental craters formed by single and multiple buried explosions and implications for volcanic craters with emphasis on maars, Geophys. Res. Lett., 39, L20301, doi:10.1029/2012GL053716.