Internet cable reveals the source of underwater vibrations

There is a long-standing challenge of identifying where the ocean waves originate. Microseisms are ubiquitous but researchers have not been able to find their sources in the sea. A new use of telecommunications equipment has changed that.

The research was published in the Geophysical Research Letters. The light that bounced back through the cable was measured. The researchers were able to identify the origins of microseisms by changing how the light came back to the source.

The source regions were between a few kilometers and 10 kilometers across, but this source region moved within a band between 7 and 27 kilometers from the coast. The source of the microseisms was not always close to the strongest vibrations. They were strongest in areas close to the water.

Waves interacting at the sea surface are what cause microseisms, and the variable nature of local winds means that wave action also changes.

Microseisms may be different depending on bathymetry and the underwater environment may have an influence on that. According to the authors, their results show the potential of DAS for understanding microseism activity.

More information: Han Xiao et al, Locating the Precise Sources of High‐Frequency Microseisms Using Distributed Acoustic Sensing, Geophysical Research Letters (2022). DOI: 10.1029/2022GL099292 Journal information: Geophysical Research Letters

The story was re-posted by the Americangeoscience Union. The original story can be read here.