Early Holocene Greenland-ice mass loss likely triggered earthquakes and tsunami

Steffen, Rebekka; Steffen, Holger; Weiss, Robert; Lecavalier, Benoit S.; Milne, Glenn A.; Woodroffe, Sarah A.; Bennike, Ole

Abstract

Due to their large mass, ice sheets induce significant stresses in the Earth's crust. Stress release during deglaciation can trigger large-magnitude earthquakes, as indicated by surface faults in northern Europe. Although glacially-induced stresses have been analyzed in northern Europe, they have not yet been analyzed for Greenland. We know that the Greenland Ice Sheet experienced a large melting period in the early Holocene, and so here, we analyze glacially-induced stresses during deglaciation for Greenland for the first time. Instability occurs in southern Greenland, where we use a combined analysis of past sea level indicators and a model of glacially-induced fault reactivation to show that deglaciation of the Greenland Ice Sheet may have caused a large magnitude earthquake or a series of smaller magnitude earthquakes around 10,600 years ago offshore south-western Greenland. The earthquake(s) may have shifted relative sea level observations by several meters. If the earthquake-induced stress release was created during a single event, it could have produced a tsunami in the North Atlantic Ocean with runup heights of up to 7.2 m in the British Isles and up to 7.8 m along Canadian coasts.

Citation

Steffen, R., Steffen, H., Weiss, R., Lecavalier, B. S., Milne, G. A., Woodroffe, S. A., & Bennike, O. (2020). Early Holocene Greenland-ice mass loss likely triggered earthquakes and tsunami. Earth and Planetary Science Letters, 546, Article 116443. https://doi.org/10.1016/j.epsl.2020.116443

• Journal Article Type: Article
• Acceptance Date: Jun 26, 2020
• Online Publication Date: Jul 10, 2020
• Publication Date: 2020-09
• Deposit Date: Jul 10, 2020
• Publicly Available Date: Jul 14, 2020
• Journal: Earth and Planetary Science Letters
• Print ISSN: 0012-821X
• Electronic ISSN: 1385-013X
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 546
• Article Number: 116443
• DOI: https://doi.org/10.1016/j.epsl.2020.116443
• Public URL: https://durham-repository.worktribe.com/output/1298111