The Noto Hanto Earthquake in 2007^#

* On March 25, at 09:42 (JST) there was a M6.9 (preliminary) earthquake at a depth of approximately 10km near the west coast of the Noto Peninsula. This event had maximum seismic intensity 6 Upper in Ishikawa prefecture, and caused damage. Also, small tsunamis were observed in the Hokuriku region, with heights of 0.2m in Nagahashi, Suzu city and Kanazawa. The focal mechanism had a compression axis in a WNW-ESE direction. This event occurred at shallow depth within the crust. Seismic activity has been a mainshock - aftershock sequence. The largest aftershocks as of 10:00 on March 26, were two M5.3 (preliminary) earthquakes that occurred at 18:11 on March 25 and at 07:16 on March 26. One of these events occurred at the northeastern edge of the aftershock region and the other occurred at the southwestern edge.

* According to the GPS data, crustal movements associated with the mainshock were centered on the Noto Peninsula, with a displacement of approximately 25cm to the southwest at the Shikamachi Togi observation station (Hakui-gun, Ishikawa prefecture).

* According to the aftershock distribution and the focal mechanism of the mainshock, it is estimated that the source is a reverse fault with a strike-slip component trending in a NE-SW direction and dipping to the southeast, which is consistent with the fault model estimated from the GPS and the seismic wave data.

* To the northeast of this event, there was an earthquake (M6.6 to 7) in 1729 and a M6.6 earthquake in 1993. However, there have been no earthquakes over M7.0 since 1600 on the Noto Peninsula nor in the neighboring areas.

* There is a reverse fault off the west coast of the Noto peninsula, which is about 20 km long, trending in a NE-SW direction with a southeast dip. Part of that fault could be associated with the recent event. Also, the Ouchigata Fault Zone is located to the southeast of the aftershock region, however it is thought that the recent earthquake had almost no effect on this fault.

* There is a possibility that aftershocks might cause shaking with intensity 5 Lower or greater within the next week. It is estimated that there is about a 70 percent chance of occurrence for M5.0 or greater aftershocks (with seismic intensity 5 Lower in some areas) within the 3 days from 10:00 on March 26.

# Japan Meteorological Agency named this earthquake the Noto Hanto Earthquake in 2007.

• Earthquake Off-shore of the Noto Peninsula on March 25
• Earthquake Off-shore of the Noto Peninsula on March 25, 2007 (Aftershock activity)
• Earthquake Off-shore of the Noto Peninsula on March 25 (Distribution of focal mechanisms in the vicinity)
• Comparison of Numbers of Aftershocks (M4.0 or Greater)
• Earthquake Off-shore of the Noto Peninsula on March 25 (Waveforms at tidal observatories)
• Major Damaging Earthquakes in the Noto Peninsula Area
• Crustal Movements Associated with the Seismic Activity Off-shore of the Noto Peninsula
• Changes in GPS data by component
• Source Fault Model Based on the GPS Observations at Reference Stations
• Moment Tensor Analyses for the Mainshock using F-net of the National Research Institute for Earth Science and Disaster Prevention
• Faults Off-shore of the Noto Peninsula
• Scenario Stress Changes in the Neighboring Areas of the Recent Earthquake