Low-frequency bursts of horizontally polarized waves in the Arctic sea-ice cover

David Marsan (1) , Jérôme Weiss (2) , Jean-Philippe Metaxian (1) , Jacques Grangeon (1) , Pierre-François Roux (1) , Jari Haapala (3)

1 LGIT - Laboratoire de Géophysique Interne et Tectonophysique
2 EDGe
3 FIMR - Finnish Institute of Marine Research

We report the detection of bursts of low-frequency waves, typically f = 0.025 Hz, on horizontal channels of broadband seismometers deployed on the Arctic sea-ice cover during the DAMOCLES (Developing Arctic Modeling and Observing Capabilities for Long-term Environmental Studies) experiment in spring 2007. These bursts have amplitudes well above the ambient ice swell and a lower frequency content. Their typical duration is of the order of minutes. They occur at irregular times, with periods of relative quietness alternating with periods of strong activity. A significant correlation between the rate of burst occurrences and the ice-cover deformation at the ~400 km scale centered on the seismic network suggests that these bursts are caused by remote, episodic deformation involving shearing across regional-scale leads. This observation opens the possibility of complementing satellite measurements of ice-cover deformation, by providing a much more precise temporal sampling, hence a better characterization of the processes involved during these deformation events.

Domaines: Géomorphologie

David Marsan, Jérôme Weiss, Jean-Philippe Metaxian, Jacques Grangeon, Pierre-François Roux, et al.. Low-frequency bursts of horizontally polarized waves in the Arctic sea-ice cover. Journal of Glaciology, 2011, 57 (202), pp.231-237. ⟨10.3189/002214311796405834⟩. ⟨insu-00647088⟩