Japan Geoscience Union Meeting 2016

Presentation information

International Session (Poster)

Symbol S (Solid Earth Sciences) » S-SS Seismology

[S-SS03] New frontiers in earthquake statistics, physics-based earthquake forecasting, and earthquake model testing

Wed. May 25, 2016 5:15 PM - 6:30 PM Poster Hall (International Exhibition Hall HALL6)

Convener:*Hiroshi Tsuruoka(Earthquake Research Institute, Tokyo Univ.), Naoshi Hirata(Earthquake Research Institute, the University of Tokyo), Danijel Schorlemmer(GFZ German Research Centre for Geosciences), Matt Gerstenberger(GNS Science)

5:15 PM - 6:30 PM

[SSS03-P03] Some development on predicting earthquake swarms using volumetric strain records

*Takao Kumazawa1, Yosihiko Ogata1,2, Kazuhiro Kimura3, Kenji Maeda3, Akio Kobayashi3 (1.The Institute of Statistical Mathematics, 2.Earthquake Research Institute, 3.Meteorological Research Institute)

Keywords:Earthquake swarm, Volumetric strain, Background seismicity, ETAS model

Off the east coast of the Izu Peninsula in Japan, there is a submarine volcanic region where earthquake swarms occur caused by magma intrusions. We investigated the background seismicity rates of the swarm activity by removing the triggering effect of aftershocks. We found that such background rate changes coincide with the changes of exponentially weighted averages of volumetric strain increments at the Higashi-Izu station. We further found that such a relationship consistently depends on the distance between the strainmeter station and the location of the swarm onset. The quantitative relationships revealed here may be used to monitor magma intrusions that drive the stress changes. The models we adopted here are purely statistical, but we added some comparisons of their performances with those by physically reasonable models.