Deep-sea Fiber Optic Cables Could Help Detect Earthquakes and More

In Feb 2021, scientists announced that they had discovered that deep-sea cables could be used to detect submarine earthquakes and tsunamis, even to monitor how climate change alters ocean currents.

Instrumenting the vast ocean floor is difficult and expensive but important for monitoring earthquakes and tsunamis. Because installing permanent sensors to monitor the ocean floor is very difficult and costly, only a few such sensor systems exist globally. However, there are countless fiber optic cables installed in the oceans worldwide. Scientists found out that vibrations, pressure and temperature changes affect, by a very small amount, the speed of light as it travels through the cable. These changes of signals can be detected by installing extremely sensitive instruments on the fiber optic cables. Scientists tested the optical-fiber link between the UK and Canada. These telecommunication cables could be used as a giant array of deep-sea scientific sensors, the researcher of UK’s National Physical Laboratory (NPL) said.

The scientists also said, this technique can be applied to the detection of earthquakes, ocean currents and more in the future. Extending the seismic network from land to the seafloor will improve human monitoring capacity of the ocean, and the understanding of the internal structure of the Earth and its dynamic behavior. It unveils an amazing opportunity to observe earthquakes in the middle of oceans at close range as well as measuring submarine volcanic eruptions and tsunamis. The same technique can monitor deep-water currents to understand the changes in climates.