Scientists have to accept their awful defeat because prediction of earthquakes has become tragically tough. Earthquakes of recent years adequately prove this point. Seismic experts are realizing that the response of rocks to strain and seismic waves is more dynamic and complex than their original assumptions. In 1910, a geologist by name Henry Fielding Reid of Johns Hopkins University propounded a theory called Elastic Rebound Theory, according to which, rocks along the faults behave like twigs to bend under stress and snap when the stress becomes powerful enough to cross the threshold. When the plates collide against one another, the rocks along faults accumulate the strain and when the strain becomes too huge to bear, earthquakes occur to release the excess strain.
This theory has its roots on strain accumulation and according to experts, it will take many many centuries before the strain accumulation becomes huge enough to trigger an earthquake. But the recent earthquakes that have occurred did not show any signs of strain accumulation and this goes to prove that the elastic rebound theory does not explain the mechanism of earthquakes fully.
The earthquakes of recent times have occurred in short intervals and hence strain accumulation could not have triggered them. In fact, some of the recent earthquakes have occurred in a cluster.
After prolonged research, scientists have proved that the strength of faults lying hundreds of kilometers away gets altered to set off tremors and for this, Landers earthquake in California of 1992 and Sumatra earthquake of 2004 are classic examples. Evidences from San Andreas Fault of Parkfield, California also give contradictory results that dilute the elastic rebound theory. The main point is it is a long way to go before scientists can boast that they can predict occurrences of earthquakes.
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