Fibre-optic cables could provide the key to detecting earthquakes and other ground movements, new research has revealed.
The future of seismology could lie in fibre-optic cables, with the method able to detect earthquakes and other ground movements, as well as seismic signals from hammer shots or wave movements in the ocean.
These are the findings of a new study conducted by the GFZ German Research Centre for Geosciences, which used fibre-optic cables to produce the densest seismological network in the world.
“Our measurements revealed structural features in the underground with unprecedented resolution and yielded signals equaling data points every four meters,” explained Philippe Jousset from the GFZ in a statement.
The scientists sent pulses of laser light through an optical fibre within the telecommunication network on the Reykjanes peninsula in Iceland, which crosses a geological fault zone between the Eurasian and American tectonic plates.
Not only well-known faults and volcanic dykes showed up in the findings, but also a previously unknown fault below the ground surface. Small local earthquakes, waves originating from large distant quakes and microseisms of the ocean floor were also recorded via the fibre-optic cable.
Requiring only one strand of a modern fibre-optic cable, the method was described as a “game changer for seismology”. The team is the first worldwide to conduct such measurements for seismological objectives, and with such a long cable, according to the statement.
The advantages of the new method are enormous, say the researchers. The fibre-optic cables spanning the globe in the dense telecommunication network could be used to detect high seismic hazards beneath megacities such as San Francisco and Mexico City in a cost-effective manner.
Future studies are planned to investigate whether deep-sea cables can also be used for seismic measurements, with the scientists expecting the cables on the sea floor to detect submarine earthquakes, ground motions of tectonic plates and variations of water pressure.
Photo credit: Timothy Neesam/ CC BY-ND 2.0