Geological and historical evidence of irregular recurrent earthquakes in Japan | Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences
At what depth do earthquakes occur? What is the significance of the depth? | U.S. Geological Survey
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Deep-sea study reveals cause of 2011 tsunami | EurekAlert!
Tohoku, Japan, Earthquake FAQ | Magnitude 9.0 | 11 March 2011 | British Geological Survey (BGS)