When it comes to predicting major earthquakes -- and tsunamis -- scientists still get caught off guard. But a new way to measure small shifts in the Earth's offshore plates using GPS sensors may accurately provide a heads up, according to a new study.
"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 University of South Florida geologist Tim Dixon.
So-called "slow-slip events" were discovered about 15 years ago, and according to Dixon and his team they can be useful in predicting major quakes and tsunamis. The researchers used high-precision GPS to check on small shifts at a fault line in Costa Rica.
That data shows a number of slow-slip events -- which release energy slowly, over weeks and months and can't be felt or measured using conventional seismographs -- in the decade leading up to the 2012 Costa Rica earthquake.
The findings were published today in the journal Proceedings of the National Academies of Sciences.