August 9, 2006 Headquarters for Earthquake Research Promotion Earthquake Research Committee

	- Northwestern Chiba prefecture	M6.0 on July 23, 2005(depth approximately 75km)
	- Off-shore of Miyagi prefecture	M7.2 on August 16, 2005 (depth approximately 40km)
	- Chuetsu region, Niigata prefecture	M5.0 on August 21, 2005 (depth approximately 15km)
	- Off-shore of Ibaraki prefecture	M6.3 on October 19, 2005 (depth approximately 50km)
	- Off-shore of Sanriku	M7.2 on November 15, 2005
	- Hyuganada	M5.5 on March 27, 2006 (depth approximately 35km)
	- Off-shore east of the Izu Peninsula	seismic activity with M5.8 on April 21, and M4.5 on April 30, 2006
	- Central Oita	M6.2 on June 12, 2006 (depth approximately 150km)

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2 Nationwide Seismic Activity by Region

(1) Hokkaido Region

On July 17, there was a M4.0 earthquake at a depth of approximately 85km under central Tokachi subprefecture.":
In this vicinity, there was a M4.7 earthquake on June 13, 2006.

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(2) Tohoku Region

On July 1, there was a M5.3 earthquake at a depth of approximately 40km off-shore of Miyagi prefecture. The focal mechanism showed a reverse fault with a compression axis in a NW-SE direction. This event occurred at the boundary between the Pacific and the continental plates.":
This event occurred near the northern edge of the aftershock region of the earthquake off-shore of Miyagi prefecture on August 16, 2005 (M7.2). In this vicinity, there was a M6.1 earthquake on December 17, 2005.

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(3) Kanto-Chubu Region

"On July 6, there was a M4.0 earthquake at a depth of approximately 50km under southern Ibaraki prefecture.":
In this vicinity, there was a M3.9 earthquake (maximum seismic intensity 3) on July 30.

"The long-term changes that have been observed since 2001 in the continuous GPS data in the Tokai region, are thought to have stopped already.":
(This evaluation is in agreement with the views presented at the procedural meeting on July 31 of the Assessment Committee for Areas under Intensified Measures against Earthquake Disaster. (see reference below))

(reference) "Recent seismic and crustal activity in the Tokai region and its vicinity" (Japan Meteorological Agency, Department of Seismology and Volcanology, July 31, 2006)

" So far, there have been no changes of activity which are likely to be associated with the so-called Tokai earthquake.
There was no remarkable seismic activity in general. The seismicity remains at a level lower than normal directly under the area from eastern Hamana Lake through central Shizuoka prefecture. In other regions, seismic activity is generally at a normal level.
The long-term crustal movements from the slow slip at the plate boundary in the Tokai region and its neighboring area, are thought to have stopped already. "

There was additional activity in the Kanto - Chubu region, as follows.
- On July 9, there was a M4.2 earthquake at a depth of approximately 25km under Tokyo Bay (maximum seismic intensity 3).
- On July 9, there was a M4.8 earthquake at a depth of approximately 10km under the ocean area near Niijima and Kozushima Islands (maximum seismic intensity 4).

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(4) Kinki-Chugoku-Shikoku Region

There is no supplementary information for the Kinki - Chugoku - Shikoku region.

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(5) Kyushu-Okinawa Region

There is no supplementary information for the Kyushu - Okinawa region.

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Reference 1 Earthquakes that are described in the "Evaluation of Seismic Activity"(Monthly Report of Seismic Activity in Japan) are events of M6.0 and greater, or events of M4.0 and greater (M5.0 or greater off-shore) that have maximum intensity of 3 or greater. Reference 2 Information that is described in the "Supplementary Information to the Evaluation" includes: 1) Reference information related to seismic activity described in the "Evaluation of Seismic Activity" 2) Recent earthquake activity over the past year related to the events described in "Major Seismic Activity" in the "Evaluation of Seismic Activity" 3) Seismic activity that has been evaluated, but not included in the "Evaluation of Seismic Activity" because it is within normal bounds and not prominent.