火山弾の飛跡の解析-放出速度と爆発圧力について-

Abstract

Night views of volcanic explosions in Sakurajima volcano were taken automatically with35mm stili cameras for the analysis of trajectories of volcanic blocks and the calculation ofthe initial velocity (v) and the ejection angle (e). The following results are obtained. 1) Theinitial velocity of the volcanic block which is ejected vertically is maximum (Vmax).2) Obtained values of Vmax are ranging from 110 m/s to 160 m/s. 3) Initial velocities fora given ejection angle are not beyond Vmax・sin1.5e. 4) It is estimated to be 130-270 barsfor pressure of volcanic explosion.