Researchers use Google undersea fiber-optic cable as sensors to detect earthquakes

The ocean area accounts for 71% of the earth’s surface area. It is relatively difficult for such a vast ocean to deploy physical sensors to detect natural activities such as earthquakes.

What is interesting is that the submarine optical cables that technology companies rely on have spread all over the world’s oceans. Can submarine optical cables be used as sensors to detect natural activities?

The answer is yes. At present, Zhongwen Zhan, an assistant professor of geophysics at the California Institute of Technology, has cooperated with Google to use submarine optical cables as physical sensors.

If an earthquake occurs, it may distort the optical signal transmitted in the submarine optical cable, and this optical signal distortion can be used to detect the earthquake in the corresponding area.

The frequency of earthquakes occurring in the ocean is relatively high, but earthquakes with a low magnitude in the vast ocean usually do not cause significant damage.

However, if an earthquake with a very high magnitude occurs, it may cause a tsunami, especially an earthquake close to the mainland or the edge of an island, which can cause severe damage.

It is more difficult for scientists to provide early warning of these earthquakes and possible tsunamis. After all, sensors cannot be installed on a large area in the vast ocean.

And Google undersea fiber-optic cables all over the ocean can be used as sensors because the waves caused by earthquakes and even hurricanes can cause distortions in the propagation of optical signals.

Under normal circumstances, Google will correct the distorted light signal to ensure the stable transmission of the signal, and now Google can also share the distorted signal with scientists.

“undersea fiber cable” by hypatiadotca is licensed under CC BY-NC-SA 2.0

From December 2019 to September 2020, the research team of assistant professor Zhongwen Zhan used the “Curie” submarine optical cable to successfully record about 20 moderately large earthquakes.

The submarine optical cables operated by Google are spread across all continents and oceans around the world. Distortion of optical signals caused by earthquakes and hurricanes is a very common phenomenon for Google.

Google will correct the distorted optical signal at the receiving end of the submarine optical cable, but Google did not expect that this distorted optical signal can also be used to monitor earthquakes on the seafloor.

The company expressed its humility and excitement about the cooperation with the optical, subsea and seismic research community, which can use our facilities to bring greater benefits to society.

At present, Google has contacted the research team of assistant professor Zhongwen Zhan to use the polarized light data transmission in Google’s submarine optical cable for research.

It is worth noting that the polarized light data shared by Google cannot see any transmitted content, so the shared data does not pose any threat to information security.

Via: theverge