Assessment of glacial-earthquake source parameters
Glacial earthquakes are slow earthquakes of magnitude M~5 associated with major calving events at near-grounded marine-terminating glaciers. These globally detectable earthquakes provide information on the grounding state of outlet glaciers and the timing of large calving events. Seismic source mode...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Cambridge University Press
2017-10-01
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| Series: | Journal of Glaciology |
| Subjects: | |
| Online Access: | https://www.cambridge.org/core/product/identifier/S0022143017000521/type/journal_article |
| _version_ | 1811155885974618112 |
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| author | STEPHEN A. VEITCH MEREDITH NETTLES |
| author_facet | STEPHEN A. VEITCH MEREDITH NETTLES |
| author_sort | STEPHEN A. VEITCH |
| collection | DOAJ |
| description | Glacial earthquakes are slow earthquakes of magnitude M~5 associated with major calving events at near-grounded marine-terminating glaciers. These globally detectable earthquakes provide information on the grounding state of outlet glaciers and the timing of large calving events. Seismic source modeling of glacial earthquakes provides information on the size and orientation of forces associated with calving events. We compare force orientations estimated using a centroid-single-force technique with the calving-front orientations of the source glaciers at or near the time of earthquake occurrence. We consider earthquakes recorded at four glaciers in Greenland – Kangerdlugssuaq Glacier, Helheim Glacier, Kong Oscar Glacier, and Jakobshavn Isbræ – between 1999 and 2010. We find that the estimated earthquake force orientations accurately represent the orientation of the calving front at the time of the earthquake, and that seismogenic calving events are produced by a preferred section of the calving front, which may change with time. We also find that estimated earthquake locations vary in a manner consistent with changes in calving-front position, though with large scatter. We conclude that changes in glacial-earthquake source parameters reflect true changes in the geometry of the source glaciers, providing a means for identifying changes in glacier geometry and dynamics that complements traditional remote-sensing techniques. |
| first_indexed | 2024-04-10T04:41:09Z |
| format | Article |
| id | doaj.art-c929174a564748e19332a47020fad149 |
| institution | Directory Open Access Journal |
| issn | 0022-1430 1727-5652 |
| language | English |
| last_indexed | 2024-04-10T04:41:09Z |
| publishDate | 2017-10-01 |
| publisher | Cambridge University Press |
| record_format | Article |
| series | Journal of Glaciology |
| spelling | doaj.art-c929174a564748e19332a47020fad1492023-03-09T12:40:28ZengCambridge University PressJournal of Glaciology0022-14301727-56522017-10-016386787610.1017/jog.2017.52Assessment of glacial-earthquake source parametersSTEPHEN A. VEITCH0MEREDITH NETTLES1Lamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USALamont-Doherty Earth Observatory of Columbia University, Palisades, NY, USAGlacial earthquakes are slow earthquakes of magnitude M~5 associated with major calving events at near-grounded marine-terminating glaciers. These globally detectable earthquakes provide information on the grounding state of outlet glaciers and the timing of large calving events. Seismic source modeling of glacial earthquakes provides information on the size and orientation of forces associated with calving events. We compare force orientations estimated using a centroid-single-force technique with the calving-front orientations of the source glaciers at or near the time of earthquake occurrence. We consider earthquakes recorded at four glaciers in Greenland – Kangerdlugssuaq Glacier, Helheim Glacier, Kong Oscar Glacier, and Jakobshavn Isbræ – between 1999 and 2010. We find that the estimated earthquake force orientations accurately represent the orientation of the calving front at the time of the earthquake, and that seismogenic calving events are produced by a preferred section of the calving front, which may change with time. We also find that estimated earthquake locations vary in a manner consistent with changes in calving-front position, though with large scatter. We conclude that changes in glacial-earthquake source parameters reflect true changes in the geometry of the source glaciers, providing a means for identifying changes in glacier geometry and dynamics that complements traditional remote-sensing techniques.https://www.cambridge.org/core/product/identifier/S0022143017000521/type/journal_articlecalvingcryoseismologyglacier geophysicsice/ocean interactionsremote sensingseismology |
| spellingShingle | STEPHEN A. VEITCH MEREDITH NETTLES Assessment of glacial-earthquake source parameters Journal of Glaciology calving cryoseismology glacier geophysics ice/ocean interactions remote sensing seismology |
| title | Assessment of glacial-earthquake source parameters |
| title_full | Assessment of glacial-earthquake source parameters |
| title_fullStr | Assessment of glacial-earthquake source parameters |
| title_full_unstemmed | Assessment of glacial-earthquake source parameters |
| title_short | Assessment of glacial-earthquake source parameters |
| title_sort | assessment of glacial earthquake source parameters |
| topic | calving cryoseismology glacier geophysics ice/ocean interactions remote sensing seismology |
| url | https://www.cambridge.org/core/product/identifier/S0022143017000521/type/journal_article |
| work_keys_str_mv | AT stephenaveitch assessmentofglacialearthquakesourceparameters AT meredithnettles assessmentofglacialearthquakesourceparameters |