Japanese

Around 5:07am, August 11th (JST; Aug 10th 8:07pm UT), 2009, a M6.4 earthquake (according to USGS) occurred at Suruga Bay. The largest intensity observed was 6-, and it was a felt earthquake in a wide area including the Kanto and Koshin’estu Regions. Tsunamis were observed at and around the Suruga Bay.

Following is a report of this earthquake. (Outreach Office)

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[Updated]

• Damage on the stone wall of Sumpu Castle (Aug 26)
• Source process inversion (Aug 25)
• Observation of aftershocks and aftershock activities (Aug 22)
• Record of the barometer (Aug 20)
• Aftershock Activities updated, time-shift made into animation (Aug 16)
• Earthquakes of the past (Aug 16)
• Analysis result of GPS observation (Aug 12)
• Suruga Kuno-san Earthquake on April 22nd, 1841 (March 2nd, Tempo 1841) (Aug 12)
• Summary by the Strong Motion Seismology Group – No.1 can be seen in English (Aug 16)
• Smoked-paper recording (Aug 12)
• GRiD MT Broadband Seismograph Record Image (J-array Observed Waveform) (Aug 11)
• Summary by the Strong Motion Seismology Group – No.2 (Aug 11)

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[Summary]

Location of the source, magnitude and the type of the earthquake

• N34.8, E138.5, depth 20km, Mj 6.5 (JMA)
• intraslab earthquake (includes reverse fault component and strike-slip component)

Relation to the Supposed Tokai Earthquake (announced by JMA)

• this earthquake is not the Supposed Tokai Earthquake
  • - the magnitude differs greatly (M8 is assumed for the Supposed Tokai Earthquake but the Suruga Bay earthquake on the 11th was M6.5)
  • - it is an intraslab earthquake (the Supposed Tokai Earthquake is a boundary earthquake on the upper side of the Philippine Sea plate

• it is not an earthquake that would trigger the Supposed Tokai Earthquake
  • - Information on the Tokai Earthquake No. 3

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[Summary by the Strong Motion Seismology Group - No.1]

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[Summary by the Strong Motion Seismology Group - No.2]

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[Aftershock Activities]