Vector chart (horizontal)

Examination of horizontal movement vectors over a one-year period revealed no marked changes in the area around Mt. Usuzan prior to the eruption.

Comparative method: average value
Standard data: 1999/3/1 - 1999/3/15
Comparative data: 2000/3/1 - 2000/3/15
Black:Bernese[IGS]

Geographical Survey Institute

Seismic Activity in Japan April 2000