摘要：We have evaluated temporal variation in strain rates in the Chubu and Kinki districts, central Japan, between 1997 and 2004 using continuous GPS data of GEONET. We found that strain rates throughout the southern part of Chubu district, including the Yoro fault and Nobi fault zone, have significantly deviated from the secular crustal deformation pattern since at least 2001. The results of an inversion procedure show that the strain rate change can be well explained by a slow slip beneath the Tokai area, suggesting that the Tokai slow event has significantly affected the crustal deformation not only in the Tokai area but also in an area located more than 100 km from the main slip area of the event. We also found that the seismicity rate has clearly decreased by approximately 50% around the Yoro fault since the latter half of 2000. The δCFF inferred from our Tokai slow slip model agrees with the observed reduction in seismicity. These results were interpreted as indicating that the seismicity, which has been decreasing for several years, is controlled by the reduction in the shear stressing-rate due to the Tokai slow slip.
