Applications of Distributed Acoustic Sensing Using Dark Fiber in Dallas, Texas
Description:
Distributed Acoustic Sensing (DAS) has recently been applied across a variety of geological and environmental conditions, including glacial, volcanic, borehole, submarine, and urban environments. Seismic monitoring using conventional broadband seismometers can be particularly challenging in urban areas due to limitations of land access. To evaluate the use of fiber optic sensing for seismic monitoring in urban environments, we monitored seismoacoustic signals in two neighborhoods of Dallas, Texas, using different configurations of Distributed Acoustic Sensing (DAS). For a 9-day pilot project in Plano, we tested a ~95 km pre-existing dark-fiber loop with an OptaSense QuantX strain Interrogator Unit (IU). Since August 2023, we have also been continuously experimenting with DAS on a ~2 km dark fiber at the Southern Methodist University (SMU) campus, deploying different configurations. The SMU DAS experiment captured both natural (e.g., earthquakes, thunderstorms) and anthropogenic signals (e.g., vehicular movements, building demolitions, subwoofers, football games). For several events, infrasound and conventional broadband measurements were made alongside the DAS measurements, enabling us to explore coupling effects. During these experiments, we observed some known and unknown challenges with using the commercial dark fiber to retrieve reliable estimates of ground motion. These include the presence of aerial fiber sections, slack fiber in handholes, and varying fiber cable coupling with the ground. We developed a computational solution to identify fiber sections unsuitable for ground motion retrieval and proposed criteria for applying frequency-wavenumber (F-K) transformation to convert DAS strain to ground velocities under different coupling conditions. The research works summarize the variety of signals we have detected and explore some applications of the signals for exploring seismoacoustic sources and subsurface structure.
Session: Fiber-optic Sensing Applications in Seismology - I
Type: Oral
Date: 4/15/2025
Presentation Time: 08:00 AM (local time)
Presenting Author: Jyoti
Student Presenter: No
Invited Presentation:
Poster Number:
Authors
Jyoti Sharma Presenting Author Corresponding Author jyotis@smu.edu Southern Methodist University |
Stephen Arrowsmith sarrowsmith@smu.edu Southern Methodist University |
Chris Hayward hayward@isem.smu.edu Southern Methodist University |
Heather DeShon hdeshon@smu.edu Southern Methodist University |
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Applications of Distributed Acoustic Sensing Using Dark Fiber in Dallas, Texas
Session
Fiber-optic Sensing Applications in Seismology