A Kinematic GPS Survey at the Northern Part of Kagoshima Bay, Japan

Abstract

Kagoshima Bay is a volcanologically interesting area which is divided into two parts by the active Sakurajima volcano (Fig. 1). The Aira Caldera is situated at the northern part of the bay and was formed by a large eruption about 22,000 years ago (Aramaki,1984). The existence of several craters are inferred from volcanic sediments, however, details are not clear because most parts of the caldera are undersea. We undertook a continuous kinematic GPS survey there for the purpose of detecting geoid undulations caused by the geological structures of the volcanoes.