A distinction technique between volcanic and tectonic depression structures based on the restoration modeling of gravity anomaly: a case study of the Hohi volcanic zone, central Kyushu, Japan

In this study, we propose a numerical modeling technique which restores the gravity anomaly of tectonic origin and identifies the gravity low of caldera origin. The identification is performed just by comparing the restored gravity anomalies with the observed gravity anomalies, thus we do not need detailed geophysical and geological information around the buried caldera. The technique has been successfully applied to distinguish the gravity low originated in the buried Shishimuta caldera from other gravity lows in the Hohi volcanic zone, central Kyushu in Japan.