Recent vertical movements in the Japanese Islands have been clarified based on the results of repeating surveys of the first-order benchmarks. Additionally, in recent years, the survey results by GNSS (Global Navigation Satellite System) have come to be used. The cumulative changes in the results of the first-order benchmarks, harmonically appear in the terrain. Mountains are relatively uplifted, and basins and plains have subsided. In the uplift and subsidence units, there are geodetic blocks with tilting and reversal movements. At the foot of Mt. Asama, the surrounding area was uplifted during periods of volcanic activity, suggesting a relationship with magmatic activity. According to the vertical variation of GNSS observations during the last 10 years, two uplift areas are found to intersect: one along the Honshu arc in the NE-SW direction and the other in the NNW-SSE or N-S direction.
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