Vol.44-2 ABSTRACT2
AbstractGSI's nationwide GPS array, which is named GEONET, has been expanded, and we can now get very detailed information on crustal deformation and water vapor distribution. Since we have collected more than one year data, we estimated horizontal crustal displacement velocity field with respect to stable interior of the Eurasian plate by using one year continuous data. The result suggests that a plate boundary runs form Shizuoka to Niigata. The western half of it moves eastward except for the southern part of Shikoku Island and Kii Peninsula, where interplate coupling between the Eurasian plate and the Philippine Sea plate is observed. On the other hand, the eastern half moves westward. Besides this result, we demonstrate we can utilize GPS as seismometer by analyzing 1-Hz GPS data at the time of the 1996 Hyuga-Nada earthquake. However, GEONET still has several problems. For example, three types of pillars are used, and mixture of these brings significant satellite elevation cutoff dependency on baseline vector and tropospheric delays. We describe a few problems here. |