February 1, 2023

Scientists turn submarine fiber optic cable into a seismograph

Scientists turn submarine fiber optic cable into a seismograph

Researchers used existing submarine fiber optic cables as a network of seismographs to collect unique data on Earth's tectonic activity.

Seismologists currently receive almost everythingdata from instruments located on land, which makes up only a third of the planet’s surface. This limits the collection of information and knowledge about tectonic movements. To increase the full picture, sensors are needed at the bottom of the ocean, but the long-term placement of equipment even a few kilometers from the coast is associated with service and access issues.

Therefore, a team of geophysicists from CaliforniaUniversity of Berkeley has decided to use the existing infrastructure of the underwater highways of the Internet. Light passes through these lines, which is scattered and distorted if the cable moves or changes its orientation. By observing these changes, you can determine exactly where and how much the fiber is bent.

Using the method of distributed acoustic sounding, the researchers recorded seismic activity and its source using a 20-km cable as a network of thousands of motion sensors.

Scientists turn submarine fiber optic cable into a seismograph

The information collected in this way allowed geologists to map previously unknown faults in the Gulf of Monterey and accurate patterns of water movement.

According to the team, the main advantage is that there is no need to install additional equipment along the entire length of the cable, just connect to its end.

The signals used for research can interfere, but scientists are already working on a solution to this problem.

Recall that at the beginning of the year, an experiment using 16QAM modulation allowed to achieve a record transfer rate of 26.2 TB / s via a transatlantic cable owned by Facebook and Microsoft.