Japanese megaquake and tsunami

This morning I woke to the news that a massive (8.9 Mw) earthquake had struck the eastern coast of Honshu, the largest Japanese island. Preliminary data about the earthquake has been posted on the British Geological Survey website. The earthquake predictably triggered a devastating tsunami that has swept inland and the BBC has some extraordinary aerial footage of the wave taking ships, vehicles, bridges and buildings with it. This is obviously a terrible event for Japan and its people and we do not yet know the full extent of the destruction and the likely number of casualties. It is also an awesome reminder of the catastrophic geological forces that can be unleashed by our planet’s internal dynamics.