This lecture is organized by TUM-IAS in association with the Institute for Astronomical and Physical Geodesy, TUM.

Title: “A Broader Look at the Magnitude-9 Tohoku Earthquake”

Abstract:

For all the attention devoted, understandably, to the catastrophic effects of the March 11th earthquake, detailed discussion of the causes has taken place mainly among circles of experts. This talk, aimed toward a multidisciplinary scientific audience, offers a broader view of the earthquake itself, as seen by a geophysicist. Prof. Fumiko Tajima, previously of Hiroshima University and currently at LMU, studies the physical background that dominates earthquake occurrences and rupture processes, as well as Earth’s deep interior structure, by analyzing seismic wave data. The Tohoku-Oki earthquake took place with a moment-magnitude (Mw) 9.0 at the plate boundary between the subducting Pacific plate and the overriding North American plate. In this subduction zone a large earthquake (~Mw7.5) was anticipated to occur with a recurrence interval of 30 to 40 years; the previous event (Mw7.5) occurred in 1978. After an Mw7.2 event in the vicinity on March 9, 2011, the Japan Meteorological Agency forecast aftershock activity, possibly including events with an Mw of over 6; that event, however, turned out to be a mere foreshock to the Mw9.0 megathrust earthquake, which released about 500 times as much seismic energy as the Mw7.2 event. Prof. Tajima will briefly explain how Japan has prepared for earthquake hazards since the 1995 Great Hanshin earthquake disaster (Mw6.8) – by building the world’s most dense seismometer network and the most extensive earthquake early-warning system – and then will present the reality of the unprecedented Mw9.0 earthquake.

The lecture can be attended without previous notice.