MeSO-net を用いたバックプロジェクション法による関東地方の中規模地震の破壊過程の解析

Abstract

The current study aims to obtain the rupture process of moderate-size earthquakes in space and time by using waveforms in the Metropolitan Seismic Observation Network (MeSO-net). The MeSO-net, in which all stations were established in 2012, is high-density seismograph network in and around the Tokyo metropolitan area, Japan. The average station-to-station distances in MeSO-net are several kilometers. The average intervals are less than a quarter of existing seismic networks in Japan, where the average distances in K-net and KiK-net are about 20 km. Then, we analyze the fault motion of moderate-size earthquakes in and around Kanto area, Japan by applying the back-projection method to seismic waveforms in MeSO-net. We construct detail images of the rupture process of moderate-size earthquakes. As a result, the spatial resolution of the rupture process for M5.1 earthquake is 0.5 km.