Tsunami warning for fiber cables under the sea

– The infrastructure of submarine optical fiber connections will act as a large-scale system for monitoring earthquakes and ocean currents. Giuseppe Marra, a researcher at the National Physical Laboratory (NPL) in the UK, says that expanding our seismic monitoring mission under the sea adds valuable knowledge about the Earth’s interior.

Installing permanent sensors at sea for this type of monitoring is expensive and complicated. Thus, even though 70 percent of the earth’s surface is covered by water, all seismic stations are on the ground.

Sensitive to light wave motion

Today, there are more than 430 optical fiber cables at the bottom of the world’s oceans, spread over 1.3 million kilometers. NPL researchers and their collaborators say they could be used as deep-sea science sensors to detect changes in ocean currents caused by earthquakes, tsunamis and climate change.

The very fast transmission of light through the fiber cable responds to disturbances such as currents, bursts and wave motions below the surface. These small deviations can be captured by highly sensitive measuring instruments and act as seismic information.

Tested at a distance of 600 miles

Now researchers have tested their theory on the optical fiber connection between the UK and Canada. According to the researchers, the nearly 600 km long EXA infrastructure connection helped detect so-called ocean signals such as earthquakes and waves and currents.

– This creates a fantastic opportunity to closely monitor earthquakes in the middle of the oceans and increase the likelihood of measuring other natural phenomena such as volcanic eruptions and tsunamis in the future, says Brian Babti, an earthquake expert at the British Geological Survey.

The project is supported by Google, the University of Edinburgh, British Geological Survey and the Istituto Nazionale di Ricerca Metrologica in Italy.

Source: BBC