From the ice pack to the earth’s crust : the laws of scale of fracturing

Figure 3 – Champ de déformation cisaillante (a) et divergente (b) de la banquise arctique obtenue par corrélation d’images satellite radar pour la période du 26 mars
au 1er avril 2007.
Source : Images de la physique 2010 CNRS.

The ice pack - this thin film of ice a few metres thick forming on the surface of the polar oceans - and the earth’s crust exhibit surprisingly similar mechanical behaviours. Both have a highly intermittent fragile behaviour, for which the deformation is concentrated along very narrow fault zones. This deformation is characterized by episodes of high activity interspersed with calmer periods of variable duration. Based on the mechanical interactions between faults and
fractures emerge a complex collective behaviour characterized by a surprising entanglement between the scales of time and space. To push the comparison between these two objects a priori so different allows to reveal the nature of some underlying processes.

 

Texte intégral

Article paru dans "Images de la Physique" 2010 (CNRS) :
From the ice pack to the earth’s crust : the laws of scale of fracturing
Jérôme Weiss, Laboratoire de glaciologie et géophysique de l’environnement, UMR 5183, CNRS/UJF, Grenoble
David Marsan, Institut des Sciences de la Terre, UMR 5275, CNRS / Univ. Savoie Mont Blanc / Univ. Grenoble 1 / IRD, Chambéry

 

–  Images of physics, CNRS