Scientists from the California Institute of Technology, United States, found a way to detect earthquakes using what’s already there: the more than a million kilometers of fiber optic telecommunication cables that lie at the bottom of the oceans.
“This new technique can really convert the majority of submarine cables into geophysical sensors that are thousands of kilometers long to detect earthquakes and possibly tsunamis in the future,” says Zhongwen Zhan, assistant professor of geophysics at Caltech. “We believe this is the first solution for monitoring seismicity on the ocean floor that could feasibly be implemented around the world.”
The research was made in a mission to avoid the complicated setup of seismometers that could track Earth’s movements under the waters where the temperature is rather constant with few disturbances. Down there, any sudden and dramatic disruption in the polarization – the oscillation of the electric field that goes from one end of the cable to the other – due to earthquakes and storms is easily identifiable. And since polarization can be measured up to 20 times per second, any warning of seismic activity could be delivered almost instantly.