A strong aftershock has rocked Japan on 11 April. USGS reported a magnitude of 6.7, while EMSC estimated M6.6. A tsunami warning has been released by the Japan Meteorological Agency for the eastern coast of Japan’s Honshu Island. UPDATE 13:06 MEST: The Tsunami warning has been cancelled.USGA reports instrumental intensities of up to VIII. The earthquake occured onshore, about 30 km W of the coast.
The Tsunami warning is currently in effect for north-eastern Honshu, expected wave heights are about 1 m:
The intensity and frequency of aftershocks due to the M9.0 Tokohu event is incredible. Until now, 52 aftershocks with magnitudes greater than 6.0 have been measured, three of them stronger than M7.0. EMSC data illustrate the spatial distrubution of earthquakes since the M9.0 event colored by depth:
The depth-distance distribution allows imaging the geometry of the subduction zone. USGS has prepared a great graphic to illustrate that:
On Saturday, the Wall Street Journal had a report on paleoseismological investigations in Japan by Shishikura.