[PapaBear3625]

During the underwater test, they were able to measure a broad range of frequencies of seismic waves from a magnitude 3.4 earthquake that occurred 45 kilometers inland near Gilroy, California, and map multiple known and previously unmapped submarine fault zones, part of the San Gregorio Fault system. They also were able to detect steady-state ocean waves—so-called ocean microseisms—as well as storm waves, all of which matched buoy and land seismic measurements.

I wonder how well this system would work to detect passage of submarines, and whether that's the real purpose of the research?

[conservatism_IS_compassion]

Hmmm . . .

[newfreep]

I’ve always wondered why submarines have never cut these cables?

It would certainly be a nightmare to splice the cables back to re-establish connection.

[FreedomPoster]

Seems very likely. There’s big money in that sort of research. I saw it with underwater acoustics many years ago.

[2001convSVT]

Theoretically, any change in pressure should effect the strain on the fiber optic cable. The difficult part is detecting the very small signals over background noise and pinpointing its location within a worthwhile accuracy.