It's the holy grail of seismologists and geologists: finding a reliable clue as to when, where, and with what magnitude the earth will shake next. So far this century, more than a million people have died due to an earthquake, not counting the astronomical cost to infrastructure and the economy, particularly in the poorest countries. Now, French scientists have detected a precursor phase that begins hours before a large earthquake occurs. And, as detailed in the magazine Science, have achieved this by analyzing the tiny movements recorded by the GPS. These researchers believe that the deployment of detection networks around the main faults could help find that holy grail.
BARACA, project to determine the risk of earthquakes in southern Spain
The State Research Agency has just approved a project to thoroughly investigate the complex set of open faults between the southeast of the Eurasian plate and the north of the African one. From the northeast of Morocco to beyond Alicante, passing through the Alboran Sea, the encounter between both plates subjects the boundaries of the terrain to great stress, fractured forming faults. The deep knowledge of these faults and the determination of the seismic risk is one of the main objectives of this project, named BARACA.
The researcher from the University of Granada Jesús Galindo is one of the BARACA researchers, where geodesists, seismologists, geologists or engineers from several Spanish universities intervene. "There are faults, such as those of San Andrés, Japan or the coast of Chile, that are very clear, with a single plane and where the deformation is not distributed," he explains. It is on these faults where the most catastrophic earthquakes occur. «And then, there are areas like here at the contact between the Eurasian and African, where there are many small faults, so the deformation is much more distributed. The situation we have is much better because the small faults are becoming apparent. There is no great one that accumulates great energy. It is true that we have many earthquakes, but they are not like those in Japan, Chile or the west coast of the United States.
Even so, there is a relative risk and every few years an earthquake of magnitudes similar to those suffered by Turkey in February can occur. BARACA is a new attempt to anticipate as much as possible.