Magnitude 6.7 quake in the southwestern Ryukyu Islands, Japan

Last updated: 2018-03-26 (84) 17:50:56 UTC

Global view of quake


The Anza group at the University of California San Diego operates a broadband seismograph network consisting of 17 three component broadband seismograph stations centered near Anza, California (see map).

On Sunday August 16 2009 at 5:05 PM (PDT) we recorded an earthquake (preliminary Mw 6.7) located in the southwestern Ryukyu Islands, Japan.

If you have felt this quake, the USGS would like to know. Please add your comments to the USGS page "Did you feel it?".

View the most recent map of local events near San Diego or a slightly wider regional view of events recorded by ANZA, or a map of events recorded by ANZA from around the globe.

Initial source parameters for this tremor are indicated below. The epicentral distance (i.e. the distance separating the epicenter and the closest station in the recording network) for Anza is 11031 km (99.16 degrees).

This map shows the mainshock as a red star. Associated aftershocks are orange stars. Anza network stations are yellow triangles. Gray lines are major rivers.

Event Map

Global mecator event map

Event Parameters

Latitude Longitude Origin time (UTC) Origin time (PDT) Depth (km) Mw Author
23.5070 123.5940 08/17/09 (229) 00:05.47 08/16/09 (228) 5:05 PM 10 6.7 QED

* The location and magnitude determined for this event are preliminary and are subject to change upon further review of seismic data.

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Of local interest:

We operate a broadband station at Piñon Flats Observatory. At 17:19 (PDT) station PFO recorded the Pdiff wave from this event. Here is a view of that event as picked by our analyst. A red Pdiff indicates a P–diff wave arrival, a red S indicates an S wave arrival.

3 component seismometer recordings at Piñon Flats Observatory

View a larger image showing the waveforms recorded at Piñon Flats Observatory.

Visit the IRIS website with additional links to seismic data for this event.

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