inputs: hypothesis: Earthquakes have the potential to generate a tsunami. premise: Quake measuring 6.9 off Japan's Honshu coast November 14, 2005 An earthquake measuring 6.9 on the Richter Scale has been reported off the coast of Japan's main island, Honshu . Whilst a major earthquake, the epicentre was well away from any population centres, and initial tsunami warnings predicting half-meter surges were later withdrawn.