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Grain size-sensitive creep in ice II

T. Kubo·W.B. Durham·L.A. Stern·S. H. Kirby
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Abstract

Rheological experiments on fine-grained water ice II at low strain rates reveal a creep mechanism that dominates at conditions of low stress. Using cryogenic scanning electron microscopy, we observed that a change in stress exponent from 5 to 2.5 correlates strongly with a decrease in grain size from about 40 to 6 micrometers. The grain size-sensitive creep of ice II demonstrated here plausibly dominates plastic strain at the low-stress conditions in the interior of medium- to large-sized icy moons of the outer solar system.

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T. Kubo, W.B. Durham, L.A. Stern, S. H. Kirby. 2006. Grain size-sensitive creep in ice II. https://doi.org/10.1126/science.1121296

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