Collaborative Research/EAGER: Toward Long-Distance Ocean and Seismic Sensing on Optical Telecommunications Infrastructure

University Of Washington, Seattle WA

Investigators

Abstract

The PIs request EAGER funding to test the feasibility of making undersea observations of seismic and oceanic processes across ocean basins on existing telecommunications cables. The project will provide partial support for two graduate students The PIs plan to compare three fiber-optical methods, Ultra-stable Laser Interferometry (ULI), Distributed Acoustic Sensing (DAS) and a long-range polarization-based method simultaneously on a telecom cable on the seafloor of Puget Sound, in Saratoga Passage, between Whidbey and Camano Island. The physics linking geophysics and ULI signals and other new techniques, like Distributed Acoustic Sensing (DAS) and the new long-range polarization-based method is limited and needs to be investigated further. There haven’t been field demonstrations showing the potential capability to resolve signals from earthquakes, tidal signals, or whale vocalizations. The current installation gives the PIs an ideal opportunity to compare the three fiber-optical methods simultaneously on a single cable with individual seismic signals arriving at various angles and varying tidal currents. These measurements would provide the first data on relative sensitivities and provide preliminary data to support future NSF proposals. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.