<p>Monitoring subtle shifts in the Earth's offshore plates can provide accurate forecasts of earthquake magnitude and tsunami potential, says a study by an international team of scientists.<br /><br /></p>.<p>This geological phenomenon called "slow slip events" or silent earthquakes is a useful tool in identifying the precursors to major earthquakes and the resulting tsunamis, the findings showed.<br /><br />"Giant earthquakes and tsunamis in the last decade - Sumatra in 2004 and Japan in 2011 - are a reminder that our ability to forecast these destructive events is painfully weak," said Tim Dixon from University of South Florida.<br /><br />Slow slip events have some similarities to earthquakes - caused by motion on faults - but release their energy slowly, over weeks or months, and cannot be felt or even recorded by conventional seismographs, Dixon said.<br /><br />The scientists used high precision GPS to measure the slight shifts on a fault line in Costa Rica, and found that better monitoring of these small events can lead to better understanding of maximum earthquake size and tsunami risk.<br /><br />They studied the Sep 5, 2012 earthquake on the Costa Rica subduction plate boundary, as well as motions of the Earth in the previous decade.<br /><br />The 7.6-magnitude quake was one of the strongest earthquakes ever to hit the Central American nation and unleashed more than 1,600 aftershocks.<br /><br />Marino Protti, one of the authors of the paper and a resident of Costa Rica, has spent more than two decades warning local populations of the likelihood of a major earthquake in their area and recommending enhanced building codes.<br /><br />The study appeared in the journal Proceedings of the National Academies of Sciences.<br /></p>
<p>Monitoring subtle shifts in the Earth's offshore plates can provide accurate forecasts of earthquake magnitude and tsunami potential, says a study by an international team of scientists.<br /><br /></p>.<p>This geological phenomenon called "slow slip events" or silent earthquakes is a useful tool in identifying the precursors to major earthquakes and the resulting tsunamis, the findings showed.<br /><br />"Giant earthquakes and tsunamis in the last decade - Sumatra in 2004 and Japan in 2011 - are a reminder that our ability to forecast these destructive events is painfully weak," said Tim Dixon from University of South Florida.<br /><br />Slow slip events have some similarities to earthquakes - caused by motion on faults - but release their energy slowly, over weeks or months, and cannot be felt or even recorded by conventional seismographs, Dixon said.<br /><br />The scientists used high precision GPS to measure the slight shifts on a fault line in Costa Rica, and found that better monitoring of these small events can lead to better understanding of maximum earthquake size and tsunami risk.<br /><br />They studied the Sep 5, 2012 earthquake on the Costa Rica subduction plate boundary, as well as motions of the Earth in the previous decade.<br /><br />The 7.6-magnitude quake was one of the strongest earthquakes ever to hit the Central American nation and unleashed more than 1,600 aftershocks.<br /><br />Marino Protti, one of the authors of the paper and a resident of Costa Rica, has spent more than two decades warning local populations of the likelihood of a major earthquake in their area and recommending enhanced building codes.<br /><br />The study appeared in the journal Proceedings of the National Academies of Sciences.<br /></p>