Observations Within Cavities at the Bed of the Glacier Østerdalsisen, Norway

• Published in: Journal of Glaciology
• Main Author: Theakstone, Wilfred H.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 1979
• Subjects: Earth-Surface Processes; Norway; glacier; Journal of Glaciology
• Online Access: http://dx.doi.org/10.1017/s0022143000029890; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000029890

Abstract Basal ice at the glacier Østerdalsisen commonly deforms under stress within cavities at the glacier bed. Some ice subject to rapid strain, however, fails in a brittle manner. The creep-rate of basal ice is influenced by sediment particles within it, and by ice grain-size and structural anisotropy; a flow law for such ice has not been derived experimentally. Near the glacier bed, particles enclosed in ice may migrate as a result of stress concentration, bubbles may be flattened, and anisotropic structures may develop. Recrystallization leads to grain-size changes. Both regelation spicules and layers of regelation ice, generally thin, form within subglacial cavities but their occurrence is limited. Regelation-ice formation has a significant influence on the distribution of rock debris at the ceilings of subglacial cavities.