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Abstract The Ross Ice Shelf (RIS) is host to a broadband, multimode seismic wavefield that is excited in response to atmospheric, oceanic and solid Earth source processes. A 34-station broadband seismographic network installed on the RIS from late 2014 through early 2017 produced continuous vibrational observations of Earth's largest ice shelf at both floating and grounded locations. We characterize temporal and spatial variations in broadband ambient wavefield power, with a focus on period bands associated with primary (10–20 s) and secondary (5–10 s) microseism signals, and an oceanic source process near the ice front (0.4–4.0 s). Horizontal component signals on floating stations overwhelmingly reflect oceanic excitations year-round due to near-complete isolation from solid Earth shear waves. The spectrum at all periods is shown to be strongly modulated by the concentration of sea ice near the ice shelf front. Contiguous and extensive sea ice damps ocean wave coupling sufficiently so that wintertime background levels can approach or surpass those of land-sited stations in Antarctica.
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Erebus low-noise broadband network
We propose a state-of-the-art 5 to 8-station broadband network that includes robust low-noise shallow-drilled posthole broadband seismometer installations. We will require (Iridium) real-time telemetry, and free and open data streams, and power systems that allow close to year-round operation (year-round would be the goal). In the middle field season of this 4-year deployment, we would also like to conduct an experiment with the nodal 3-component instruments to investigate the properties and geometry of Erebus' near surface magma reservoir. Following rescoping, the project was amended to have all field work accomplished by PASSCAL Polar staff (with no field work funded for the PI team). Following further COVID-related supplemental 2020 iscussions, the end date was extended to 9/1/23 (4-years duration).
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- PAR ID:
- 10471636
- Publisher / Repository:
- International Federation of Digital Seismograph Networks
- Date Published:
- Format(s):
- Medium: X Size: 200000 MB
- Size(s):
- 200000 MB
- Location:
- Erebus Volcano, Ross Island, Antarctica
- Sponsoring Org:
- National Science Foundation
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