━━━━━━━━━━━━━━━━━━━━━━━━
2019年7月4日 Ridgecrest earthquake (foreshock)
━━━━━━━━━━━━━━━━━━━━━━━━
1.地震について (Earthquake Information)
----------------------------------------------------
2019/06/18,22:22:20.3 38.59 139.4847 9.0 6.8
----------------------------------------------------
Table1. Earthquake information. Origin time, Epicentral latitude, longitude, depth, and JMA magnitude from the left.(ref. SCEC catalog)
Fig.1. Event location.
2.観測記録 (Observed Records)
Fig.2. Peak Ground Acceleration (left) and Peak Ground Velocity (right).
Fig.3. MMI seismic intensity.
3.解析結果 (Analytical Result)
Fig.4. Time history of the estimates for source parameters by the IPF method (Wu et al., 2015). The error of epicenter, depth, error of origin time, JMA magnitude are shown. The left edge of the horizontal axis shows the origin time of the event and the line starts when the IPF was triggered.
Fig.5. Simulation of IPF method (Wu et al., 2015). The triangles show the stations, and the red ones are used for the simulation. The star shows the location of an earthquake. The color of the samples is proportional to the likelihood of the hypocenter location.
-------------------------------------------------------
38443183.CI.CLC. -117.598 35.816 1.560 3.088 14.799 6.4 5.9
38443183.CI.Q007 -117.667 35.610 0.629 5.455 18.006 6.4 5.1
38443183.CI.SRT. -117.751 35.692 1.646 4.528 22.176 6.4 5.9
38443183.CI.CCC. -117.365 35.525 0.737 4.748 23.751 6.4 5.2
38443183.CI.TOW2 -117.765 35.809 1.059 5.138 26.072 6.4 5.5
38443183.CI.SLA. -117.283 35.891 0.667 5.168 28.811 6.4 5.1
38443183.CI.LRL. -117.682 35.480 1.084 5.258 29.689 6.4 5.6
38443183.CI.WRC2 -117.650 35.948 1.049 5.328 29.926 6.4 5.5
38443183.CI.WBM. -117.890 35.608 0.990 6.763 36.435 6.4 5.5
38443183.CI.WVP2 -117.818 35.949 0.478 6.790 39.084 6.4 4.8
Observed/Estimated Mw(median) tauc 6.4 5.5 1.0
-------------------------------------------------------
Table2. Analytical results using Tau_c method (Wu and Kanamori, 2005). Station ID, Station longitude, latitude, tauc, P-arrival time, epicentral distance(km) , magnitude, and estimated magnitude from the left.
Wu, Y. M. and H. Kanamori (2005). Experiment on an onsite early warning method for the Taiwan early warning system, Bull. Seism. Soc. Am., 95, 347-353.
Wu, S, Yamada, M., K. Tamaribuchi, and J. Beck (2015). Multi-events Earthquake Early Warning algorithm using a Bayesian approach. Geophysical Journal International, Vol.200-2, pp.789-806, doi: 10.1093/gji/ggu437, 2015.2. journal pdf
Acknowledgement
SCEC(Southern California Earthquake Center)の震源情報、強震波形を利用しました。
緊急地震速報を発表した地震の解析結果
山田真澄 ホーム