Geotechnical Engineering Aspects of the Catastrophic Tohoku (Japan) Earthquake of March 11, 2011: the Review of First Results

Geotechnical engineering aspects of the catastrophic earthquake, which occurred in Japan on March, 11, 2011 and called Tohoku earthquake are discussed. A review is presented of the first results obtained mainly by Japanese scientists based on records of seismic networks of Japan K-NET, Kik-net and on GPS data. The basic concepts of seismic zoning in Japan and the location of the Tohoku-oki earthquake on the seismic zoning maps are described, as well as models of the source process obtained by various authors based on teleseismic data, strong motion data, GPS data, and tsunami observations. The recorded peak accelerations and velocities and their correspondence to the current empirical attenuation curves are discussed. The records of the Tohoku earthquake made by Japanese seismic networks K-NET, Kik-net and some others represent unique seismological material and the most complete seismic database (including vertical array records) in the near-source zone of a strongest earthquake with magnitude M-w = 9. These data will be studied by seismologists all over the world for many years and, probably, they will answer many questions of geotechnical seismic engineering.