This is a report describing an ambitious application of shock wave research to volcanology. In the explosive eruption of a volcano, a shock wave or a blast wave is created, which as it propagates, exhibits characteristics related to the nature of the pressure release at the mouth of the volcano. Hence, it was decided that it would be worthwhile to measure its overpressure in situ via a pressure transducer installed at a point not very far away from its mouth and then to use the measured data to validate a numerical scheme which, to identify the initial energy release of the eruption, was constructed for shock wave propagation over the three-dimensional geometry. The Shock Wave Research Center, Institute of Fluid Science, Tohoku University began a project in 1995 to study the shock wave dynamics of volcanic eruption, by measuring the time variation of blast wave overpressures in situ at Mount Aso near Kumamoto. This paper describes the preparation of the overpressure measurement, still awaiting an eruption, and the result of a three-dimensional fine numerical simulation, which is ready to be compared with the measured data.