Dislocations and plastic deformation of ice

In Situ Mechanical Properties of Shallow Gas Hydrate Deposits in the Deep Seabed

“…It has been confirmed with ice that such small cracks will be generated when stress is applied (Gold, ), leading to the failure of the material. The cracks that cause failure are scratches on the material surface, and there are also cases of concentration and movement of dislocations in the structure which are crystallographic defects (Taylor, , Webb & Hayes, ). In the case of hydrates in nature, it is inferred that narrowing in the crystal grain boundaries during the crystal growth process and the fine particles left behind are the causes of failure at a low stress level.…”

Dislocation motion in ice: A study by synchrotron X-ray topography

“…Shoaib Ahmad and R. W. Whitworth Hayes and Webb (1965) and Webb and Hayes (1967) obtained clear topographic images by the Lang technique showing dislocations formed by the deformation of dendritic crystals of ice, and Hart (1980) has also reported obtaining topographs of ice at about that time. Over the following years, X-ray topography with conventional or high-power X-ray tubes has been extensively used in the study of ice.…”

Planetary Ices Attenuation Properties

“…With the development of the X-ray topographic method in the 1970s, dislocations located on various planes within single ice crystals were observed (e.g., Webb and Hayes 1967;Fukuda et al 1987;Duval et al 1983;Baker 1997). The most significant finding from these studies was the remarkable anisotropy in the plastic deformation of ice, such that the creep rate by slip on the basal plane (in particular, the so-called glide set of basal planes; Whitworth 1980) is roughly 10 4 times faster, at a given stress, than creep by non-basal slip.…”