The powerful earthquake with a magnitude of 7.5 that has so far killed more than 2,600 people in Turkey and Syria and also affected Cyprus, Jordan, Lebanon, Iraq, Georgia, and Armenia has shaken up a lot of worried people in the region.
While current earthquake monitoring technology can provide early warning for earthquakes on land, those that occur on the seabed are usually detected late – up to tens of seconds after they started and can result in fatalities.
In a new study published in Nature’s Scientific Reports journal under the title “Magnitude estimation and ground motion prediction to harness fiber optic distributed acoustic sensing for earthquake-early warning,” an international team of researchers at the Hebrew University of Jerusalem (HU) showed that existing fiber-optic cables used worldwide for Internet communication on the seabed can detect seabed earthquakes half a minute earlier than current methods.
The team led by Dr. Itzhak Lior from HU’s Institute of Earth Sciences at showed that optical communication fibers – including fibers from commercial communication companies – can provide earthquake early-warning systems (EEW).
How can you predict an earthquake?
Numerous earthquakes occur every year around the world, fortunately with most of them weak in strength and causing no damage – but strong ones may occur and cause mass disasters and many casualties. While current earthquake-monitoring technology can rapidly provide early warning for powerful tremors on land, those that occur on the seabed are usually detected up to tens of seconds after they start. The largest and most damaging earthquakes on Earth occur offshore, and their late detection significantly shortens warning times and our ability to prepare for them.
“Earthquakes that occur under the seabed or in areas without sensors can result in delayed detection by existing technologies, which hinders preparation,” Lior explained. “Recently, an innovative method for monitoring earthquakes using optical fibers, including those deployed worldwide for Internet communication, has been gaining momentum. In this study, we showed that optical fibers can be used instead of the traditional sensors to provide early warning, especially for earthquakes that occur at sea.”
“Earthquakes that occur under the seabed or in areas without sensors can result in delayed detection by existing technologies, which hinders preparation. Recently, an innovative method for monitoring earthquakes using optical fibers, including those deployed worldwide for Internet communication, has been gaining momentum. In this study, we showed that optical fibers can be used instead of the traditional sensors to provide early warning, especially for earthquakes that occur at sea.”
Itzhak Lior
Current solutions, such as densifying on-land seismic networks and installing cabled ocean bottom sensor networks, are implemented in Japan and Canada. However, high costs preclude their worldwide implementation. An alternative is to convert existing fiber optic cables into dense seismic networks via the novel technology of distributed acoustic sensing.
Analyzing earthquakes recorded by several optical fibers deployed on the seabed off the coasts of Greece, France and Chile, Lior and his colleagues determined the intensity of the earthquakes and their damage potential before they were felt on land. Using this technology, earthquakes on the seabed could be alerted for up to half a minute earlier than standard methods – critical seconds that can save human lives.
These findings prove that using existing fiber infrastructure can simplify and speed up the establishment and operation of earthquake warning systems, as well as improve warning times,” he continued.
“Optic fibers, including those from commercial telecommunications companies for speedy Internet, can determine the intensity of earthquakes and their damage potential very quickly, adding critical seconds of warning for destructive earthquakes. Using communication fibers from commercial companies is a very significant advantage for areas that are at risk of earthquakes such as Chile, Japan, the west coast of North America, and also Israel.”