This is the first complete account of the physics of the creep and fracture of ice, and their interconnectivity. It investigates the deformation of low-pressure ice, which is fundamental to glaciers, polar ice sheets and the uppermost region of icy moons of the outer Solar System. The book discusses ice structure and its defects, and describes the relationship between structure and mechanical properties. It reviews observations and measurements, and then interprets them in terms of physical mechanisms. The book provides a road-map to future studies of ice mechanics, such as the behaviour of glaciers and ice sheets in relation to climate change and the dating of deep ice cores. It also highlights how this knowledge is transferable into an understanding of other crystalline materials. Written by experts in the field, it is ideal for graduate students, engineers and scientists in Earth and planetary science, and materials science.

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• appears to alter the kinetics of the development of deformation textures and is, at high temperature, at the origin of recrystallization textures. The purpose of this work is to obtain a better understanding of recrystallization processes that occur in polar ice sheets and to clarify the relationship between dynamic recrystallization and textures. The study was based on two deep ice cores from Greenland and Antarctica, the GReenland Ice core Project (GRIP) and Vostok ice cores. The structure along the GRIP core displays normal grain growth in the first 100 m of the ice sheet and rotation recrystallization and migration recrystallization near the bottom. Only grain growth and rotation recrystallization appear to occur in the Vostok ice core. The transition between these recrystallization regimes was studied, estimating, for interglacial ice, the evolution with depth of the dislocation density. This calculation has shown the efficiency of grain boundary migration for the absorption of dislocations. At Vostok, the highest value of the dislocation density is found at a depth of about 1000 m and the continuous decrease in the dislocation density below this depth is related to the increase of the grain boundary migration rate. It is shown that the driving force required to initiate migration recrystallization is not reached in interglacial ice at Vostok. The observed textures were compared with those predicted by the self-consistent approach. Recrystallization textures are interpreted by assuming that the less stressed grains, i.e., the best oriented for basal slip, are favored by the size advantage of subgrains. The recrystallization textures are compared with those of other materials.

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