6 years ago when still employed by Telstra, I was in discussion with the CSIRO (Dr. Andrew Forbes,
http://www.marine.csiro.au/media/04releases/23jan04.htm ) about using out of service submarine communications cables in the Indian Ocean for the detection of nuclear weapons testing, ocean temps, earthquakes, and possible tsunamis. See
http://www.csiro.au/files/mediarelea...sNuclearIn.htm
The problem was that we needed to store soem no longer needed cable in the cable depots in Manila and Singapore - and someone would have to pay for the storage (which isn't cheap). Telstra was willing to cover their share of the costs but agreement from the other cable owners wasn't forthcoming (the cable ownership is shared).
Then a few years ago we had the devastating New Year tsunami in Asia - all those countries whose administrations who were reluctant to pay some money were the ones worst hit by the tsunami.
This technique is already in use in the Pacific by the Japanese Earthquake Research Institute
http://www.eri.u-tokyo.ac.jp/ and by the US at Woods Hole Oceanographic Institute
http://www.whoi.edu/ - both organisations with which I had corresponded.
Ron