抄録
Gravity anomalies due to the upper mantle heterogeneity around north-eastern Japan are investigated. The anomaly based on UTSU'S model is characterized by a positive anomaly around the Japan Trench and a negative anomaly in the Sea of Japan. The latter reflects the peculiar feature of the upper mantle beneath the marginal sea. The residual anomaly computed from a detailed crustal section and the observed gravity anomaly also indicate the same pattern.
A new crust-mantle model around northeastern Japan is proposed. This model explains well the various geophysical observations.
