Sandia Labs FY22 Laboratory Directed Research & Development Annual Report

ACOUSTIC SENSING ON ARCTIC SEAFLOOR USING REPURPOSED TELECOMMUNICATIONS OPTICAL FIBER.

The Cryosphere/Ocean-Distributed Acoustic Sensing (CODAS) project completed eight ground-breaking data acquisition campaigns over a two-year period on Alaska’s North Slope using Distributed Acoustic Sensing (DAS), an emerging technology that repurposes a standard telecommunications optical fiber into a kilometers-long seismic array. In this case, the seafloor fiber extends 37 km off Oliktok Point into the Beaufort Sea. The CODAS project was the first use of the DAS method in a polar coastal environment and in an area of transient sea ice. The collected data is a record of the sounds of the natural environment (ocean waves, sea ice vibration, icequakes, earthquakes) and anthropogenic sources (ships, trucks, hovercrafts). In collaboration with Sandia Alliance partner University of New Mexico,

the team was able to determine both sea ice thickness and extent with unprecedented spatial and temporal resolution. Another unique accomplishment in collaboration with Sandia National/Regional partner University of Washington showed that DAS can reproduce buoy data by recording ocean wave parameters. Oceanographic Institute, invited and contributed talks sponsored by International Circumpolar Remote Sensing Society, National Science Foundation, Seismological Society of America, and the American Geophysical Union, plus an interview on the Physics World Weekly podcast. (PI: Robert Abbott) Impacts to date include partnerships with industry including the Woods Hole

Sandia researchers begin collecting the first-ever dataset from the Arctic seafloor using distributed acoustic sensing and a fiber optic cable. (Photo by Kyle Jones)

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LABORATORY DIRECTED RESEARCH & DEVELOPMENT