
Scientists turn undersea fiber optic cables into seismographs - DoreenMichele
https://techcrunch.com/2019/11/28/scientists-turn-undersea-fiber-optic-cables-into-seismographs/
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dang
Also [https://www.wired.com/story/scientists-spot-an-undersea-
faul...](https://www.wired.com/story/scientists-spot-an-undersea-fault-using-
fiber-optic-cables/)

(via
[https://news.ycombinator.com/item?id=21660902](https://news.ycombinator.com/item?id=21660902),
but no comments there)

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peter303
The method is becoming very popular in the oil industry as a robust method of
instrumenting oil wells. Fiber can measure temperature and pressure as well as
seismic waves. A well can be a harsh environment to place electronic sensors
and the wire to power them and receive telemetry. Electronic instrument get in
the way of drilling and production. A tiny fiber has none of these problems.
Ditto for transport pipelines for trauma and leaks (pressure drops). The
limitation is a length of about ten miles- OK for wells, but not pipelines and
underseas cables.

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peter303
Fiber also can be a property surveillance tool. Place a loop around a boundary
and listen for interlopers. You quickly discover their location and time too.
A seismic DAS loop around the Stanford campus detects lots of traffic. Seismic
wavefronts propagate near vertically, while cultural nouse is most horizontal.
A clever reader can devise an algorithm to distinguish both cases.

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xvilka
Could be putting additional time cheap fiber in the all new cables a solution
to this problem? E.g. by an agreement between client companies, cable
producers, and international organizations?

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dghughes
Isn't that like using a big OTDR?

