火山噴火映像から抽出した圧力波の特徴について

Abstract

桜島火山の噴火映像に対して画像処理・解析を行った。その結果，圧力波が伝播する様子やその時空間特性を定量的に把握することが可能となった。また，球状衝撃波伝播の計算結果と比較することで，火山爆発源の物理諸パラメータについての簡単な検討を行った。

We analyzed some eruption movies of Sakurajima and Suwanosejima volcanoes. Propagation of pressure waves produced by these eruptions were clearly recognized as changes in luminance using an image processing of movies, even for the case that we could not see them by bear eyes. The apparent speeds of propagation were around 340-570 m/s at Sakurajima. Furthermore, information on wavelengths of pressure waves has been investigated quantitatively to estimate the source conditions of volcanic explosions; such as time-spatial dimension of the waves.