Revolution in earthquake detection technology

Researchers in Iceland say they have successfully used a fiber optic communication cable to evaluate seismic activity.

This cable is currently underground in many countries around the world to provide internet and television services.

Earthquake activity is often monitored by seismic meters - which are carefully and expensive calibrated devices located in sensitive locations.

The team, led by Dr. Philippe Jousset of the German Geological Research Center GFZ, tested this method using 15km of fiber optic cable that was installed between two geothermal power plants in Iceland in the year. 1994.

A laser pulse is transmitted down the cable to determine if there is any disturbance along its length.

"At first we didn't know what we could record , " Dr. Jousset told BBC News, "But we could detect earthquakes from very far away."

They also discovered vibrations due to regional traffic, seismic tremors and even pedestrians passing by. They also received signals from a strong earthquake in Indonesia.

This cable is currently placed underground in many countries around the world.(Photo: SCIENCE PHOTO LIBRARY).

Dr. Jousset said: "It's almost as good as a seismograph."

Equipment that needs to be attached to each cable to perform monitoring can be expensive, but researchers are looking for cost-effective alternatives.

If they find them, this method will be an affordable alternative to expensive seismic networks.

Dr. Elizabeth Cochran, a geophysicist who works at the US Geological Survey (USGS), said the technology could be applied to earthquake early warning systems, once " refined".

"For early warning, we do not necessarily need high-precision information, we just need to know that large ground movements are taking place in an area."

"Currently, there are thousands of kilometers of cables running underground in cities. So if we can exploit them and find a way to interpret the data correctly, there is a great potential. for dense sensor networks everywhere there are cables, " she told BBC News.

However, in addition to refining the technology, there will be more challenges for the team.

"Everything will depend a lot on the willingness to trust this idea and allow the use of their cable to a minimum or no cost of media companies," Dr. Cochran explained.

She noted that " most US companies use cables for a limited time, but suggest that they charge a long-term use."

However, Dr. Jousset's team found companies in Europe quite open to this idea.

They can conduct further research in the near future, and Jousset is optimistic about the potential of monitoring volcanic and earthquake activity of this technology.

"At present, there is more and more potential, so prices will fall. It can be put into operation in the next few years. Not everywhere, but somewhere ."