Niigata earthquake

The Niigata earthquake of June 16, 1964 had a magnitude of 7.5 and caused severe damage to many structures in Niigata. The destruction was observed to be largely limited to buildings that were founded on top of loose, saturated soil deposits. Even though about 2000 houses were totally destroyed, only 28 lives were lost (General report on the Niigata earthquake 1964). A tsunami, triggered by movement of the sea floor associated with the fault rupture, totally destroyed the port of Niigata.

The death toll of this earthquake was over 200. The Niigata earthquake has been extensively studied by Japanese seismologists, and in particular, by Keiiti Aki who introduced the concept of seismic moment, estimated its value for the Niigata earthquake based on spectral analysis of its seismic waves, and discussed the significance of seismic moment as a source parameter. This earthquake archive is created to honor Prof. Keiiti Aki for his many pioneering contributions in seismology.
Liquefaction The Niigata earthquake, together with the Alaska earthquake also of 1964, brought liquefaction phenomena and their devastating effects to the attention of engineers and seismologists. A remarkable ground failure occurred near the Shinano river bank where the Kawagishi-cho apartment buildings suffered bearing capacity failures and tilted severely (left). Despite the extreme tilting, the buildings themselves suffered remarkably little structural damage.

Sand boils and ground fissures were observed at various sites in Niigata. Lateral spreading caused the foundations of the Showa bridge to move laterally so much that the simply supported spans became unseated and collapsed

On 16 July 2007, a strong earthquake struck northwestern Japan, causing a fire and minorradioactive water leak at one of the world's most powerful nuclear power plants. At least seven people were killed and hundreds injured. Japan's Meteorological Agency measured the quake at 6.8 on the richter scale and sending aftershocks of 6.6. The U.S. Geological Survey, which monitors quakes around the world, said the initial quake registered 6.7. A tsunami watch was issued along the Sea of Japan. The predicted height of the tsunami was estimated to be 50 cm (20 inches). That earthquake sparked only a few small tsunamis, growing to be no more than about 20 cm (8 inches) tall. However, the 1964 quake and tsunami north of the current one destroyed the port of the city of Niigata