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Marie Byrd Land is a volcanically active province that overlaps with the Amundsen Sea Embayment, a region of the West Antarctic Ice Sheet that is experiencing particularly rapid ice mass loss. We locate 34 previously undetected seismic events (ML1.2–3.2) and identify 251 additional similar events from 2019 to 2024 in eastern Marie Byrd Land. Located at crustal depths and of magmatic or tectonic origin, these events significantly expand the known geographic extent of such seismicity in West Antarctica. Seismicity is primarily located at Mount Takahe, ∼25 km south of the Crary Mountains, and ∼50 km west of the Kohler Range. Long‐period earthquakes at Mount Takahe have seismic characteristics consistent with active magmatic transport at crustal depths beneath the volcano. Glacio‐volcanic feedback due to ongoing ice mass loss may increase eruption frequency from active Marie Byrd Land volcanic systems, possibly perturbing future ice mass loss rates.
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(Re)Discovering the Seismicity of Antarctica: A New Seismic Catalog for the Southernmost Continent
Abstract We apply a machine learning (ML) earthquake detection technique on over 21 yr of seismic data from on-continent temporary and long-term networks to obtain the most complete catalog of seismicity in Antarctica to date. The new catalog contains 60,006 seismic events within the Antarctic continent for 1 January 2000–1 January 2021, with estimated moment magnitudes (Mw) between −1.0 and 4.5. Most detected seismicity occurs near Ross Island, large ice shelves, ice streams, ice-covered volcanoes, or in distinct and isolated areas within the continental interior. The event locations and waveform characteristics indicate volcanic, tectonic, and cryospheric sources. The catalog shows that Antarctica is more seismically active than prior catalogs would indicate, examples include new tectonic events in East Antarctica, seismic events near and around the vicinity of David Glacier, and many thousands of events in the Mount Erebus region. This catalog provides a resource for more specific studies using other detection and analysis methods such as template matching or transfer learning to further discriminate source types and investigate diverse seismogenic processes across the continent.
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- PAR ID:
- 10543213
- Publisher / Repository:
- Seismological Society of America
- Date Published:
- Journal Name:
- Seismological Research Letters
- ISSN:
- 0895-0695
- Subject(s) / Keyword(s):
- Antarctica Seismicity
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1785/0220240076
