MAGNETOSTATIGRAPHY OF THE LATE CENOZOIC TOKAI GROUP IN CENTRAL JAPAN AND ITS SEDIMENTOLOGIC IMPLICATIONS

The Late Cenozoic Tokai Group consists of fluvial sediments with many volcanic ash layers. Based on paleomagnetic measurements and tephrostr atigraphy of this group, we have established the Tokai Polarity Superz one, which is divided into the TS-E, TO-D, TO-C, TO-B, and TO-A Polari ty Zones in ascending order. These magnetopolarity zones are correlate d with Chron 5 to 1. According to the magnetostratigraphy of the Tokai Group, sedimentation rates are at a maximum in the northwestern part of the basin and a minimum in the northeast. The depocenter collective ly migrated clockwise and tilted westward.