M 6.4 Quake Strikes SW Ryukkyu Isls, Japan

A Magnitude 6.4  Earthquake Struck Southwestern RyuKyu Islands, Japan

A strong earthquake measuring 6.4 Mw struck southwestern RyuKyu Islands, Japan, Wednesday, August 05, 2009, at 00:18 UTC, USGS reported.

So far, there have been no reports of aftershocks, which might follow later. There has continual seismic activity in the area in the past weeks.

Japan Meterological Agency (JMA) posted no No tsunami warning, however, it advised that slight sea level changes may occur.

Earthquake Details

• Magnitude: 6.4

• Date-Time:
  • Wednesday, August 05, 2009 at 00:18:00 UTC
  • Wednesday, August 05, 2009 at 09:18:00 AM at epicenter

• Location: 24.232°N, 125.007°E

10-degree Map Centered at 25°N,125°E

Earthquake Location Map. USGS

• Depth: 35 km (21.7 miles) set by location program
• Region: Southwestern RyuKyu Islands, Japan
• Distances:
  • 84 km (52 miles) ESE (103°) from Ishigaki-jima, Ryukyu Islands, Japan
  • 322 km (200 miles) E (97°) from Su-ao, Taiwan
  • 343 km (213 miles) SW (232°) from Naha, Okinawa, Japan
  • 1150 km (714 miles) NNE (21°) from MANILA, Philippines

• Location Uncertainty:  horizontal +/- 5.1 km (3.2 miles); depth fixed by location program
  Parameters NST=159, Nph=159, Dmin=366 km, Rmss=0.9 sec, Gp= 40°,  M-type=teleseismic moment magnitude (Mw), Version=6
• Source: USGS NEIC (WDCS-D)
• Event ID: us2009jyab

Historic Seismicity Magnitude 7 and Greater Earthquakes Since 1900
[Source: USGS]

Seismic Hazard Map [Source: USGS]

Major Tectonic Boundaries: Subduction Zones -purple, Ridges -red and Transform Faults -green

Related Links:

• California Earthquake Forecast 2009
• Earthquakes