Researchers Chase Tremors
If the February earthquakes in Chile made you postpone your travel plans, now may be a good time to go. German researchers say earthquakes, similar in magnitude to the one in Chile in February, are very unlikely to reoccur in the region any time soon.
By comparing GPS observations from the years leading up to the earthquake, scientists at the GFZ, German Research Centre for Geosciences, have shown a high degree of correlation between stress distributions in the earth’s crust before the quake and the subsequent fracture distributions. This has lead the researchers to believe, that the region has now expelled the causes leading up to the substantial earthquakes.
Measurements have shown that the seafloor of the Nazca plate in the Pacific Ocean were rubbing unevenly against the western boundary of the South American continent to create a tension in areas where the ocean floor got locked with the subsurface of the continent. The accumulating tension may very well have been the cause of the earthquake–reacting as a kind of safety valve or stress reliever.
The high correlation between stress-lines and fracture-lines has also increased the possibility of predicting new and similar earthquakes. In northern Chile one last tectonic gap remains and now the researchers are setting up geoscientific equipment to measure the conditions before, during and after a potential earthquake.
This, they believe, can provide them with useful information for predicting future earthquakes.
As the question of predictability arises, however, it is worth remembering that the tensions causing the February 2010 earthquakes had been building for approximately 175 years. Hopes of predictability will inevitably appear more realistic in the light of hindsight.