- 著者
-
花籠 靖
中西 一郎
森谷 武男
笠原 稔
- 出版者
- 公益社団法人 日本地震学会
- 雑誌
- 地震 第2輯 (ISSN:00371114)
- 巻号頁・発行日
- vol.43, no.2, pp.213-225, 1990-06-24 (Released:2010-03-11)
- 参考文献数
- 19
The rapid determination of seismic moment and source mechanism for near earthquakes is attempted by a moment tensor inversion of long-period seismic waves. The inversion method is based on a normal mode theory. The data for the inversion are recorded at three stations in Hokkaido, Japan. Each station is equipped with a three-components very-broad-band seismograph. Source parameters of six earthquakes (mb_??_5.5) in and around the Japan region (epicentral distances of 200 to 1500km) for the period from January to April 1989 are determind by applying the moment tensor inversion to the long-period waveform data. Changing the components (UD, NS, EW) and record length used in the inversion the stability in the moment tensor solution is examined. A good S/N ratio is required to obtain a stable solution in the inversion of three-components data from a single station. Data length of 4-8min after the earthquake origin time is enough to attain stable source mechanism determination by using the three-stations data.