Detection of topographic changes associated with volcanic activities of Mt. Hossho using D-InSAR

Abstract

The Kuju volcanic region is situated in central Kyushu, southwest Japan. Mt. Hossho, one of the active volcanoes in this region, suddenly erupted on 11 October 1995. Although the Kuju volcanic region is known as a rich geothermal field, surveying data for the topographic change around Mt. Hossho had not been obtained before the eruption. The Japanese satellite, JERS-1, had operated between 1992 and 1998, and acquired many data sets of the Kuju volcanic region before and after the eruption. The purpose of this study is to detect the topographic changes associated with a sequence of the volcanic activity of Mt. Hossho by differential interferometric technique of JERS-1/SAR data (D-InSAR). Using nine data pairs for D-InSAR, it is verified that a local area near the crater had been subsiding locally after the eruption with a small temporal change rate.