To obtain a detailed model of the three-dimensional ground structure, the microtoremor and gravity surveys were carried out around Kurikoma area, Japan, where is the source reagion of 2008 Iwate-Miyagi nairiku earthqu...To obtain a detailed model of the three-dimensional ground structure, the microtoremor and gravity surveys were carried out around Kurikoma area, Japan, where is the source reagion of 2008 Iwate-Miyagi nairiku earthquake and is located about 90 km north of Sendai. Using the microtremor data, velocity structures of shallow sediments are estimated and the results at some of the sites are reported preliminarily. We could not find the detailed velocity structure to bedrock, because small arrays for the microtremor observation were applied, However, significant structures are observed for shallow velocity structure at some sites. Furthermore, gravity data provided Bouguer anomaly, which is one of gravity anomalies, around the target area. From the Bouguer anomaly, area with low anomaly is tbund around the south-eastern area of the fault plane.展开更多
文摘To obtain a detailed model of the three-dimensional ground structure, the microtoremor and gravity surveys were carried out around Kurikoma area, Japan, where is the source reagion of 2008 Iwate-Miyagi nairiku earthquake and is located about 90 km north of Sendai. Using the microtremor data, velocity structures of shallow sediments are estimated and the results at some of the sites are reported preliminarily. We could not find the detailed velocity structure to bedrock, because small arrays for the microtremor observation were applied, However, significant structures are observed for shallow velocity structure at some sites. Furthermore, gravity data provided Bouguer anomaly, which is one of gravity anomalies, around the target area. From the Bouguer anomaly, area with low anomaly is tbund around the south-eastern area of the fault plane.