The Ice-Rock Interface and Basal Sliding Process as Revealed by Direct Observation in Bore Holes and Tunnels
Abstract The glacier bed, where basal sliding occurs, was reached by cable-tool drilling and sand-pump bailing in seven bore holes in Blue Glacier, Olympic National Park, Washington. Basal sliding velocities measured by bore-hole photography and confirmed by inclinometry are unexpectedly low, rangin...
Published in: | Journal of Glaciology |
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Main Authors: | , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Cambridge University Press (CUP)
1979
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Subjects: | |
Online Access: | http://dx.doi.org/10.1017/s0022143000030124 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000030124 |
Summary: | Abstract The glacier bed, where basal sliding occurs, was reached by cable-tool drilling and sand-pump bailing in seven bore holes in Blue Glacier, Olympic National Park, Washington. Basal sliding velocities measured by bore-hole photography and confirmed by inclinometry are unexpectedly low, ranging from 0.3 to 3.0 cm/day and averaging 1.0 cm/day. This is much less than about half the surface velocity of 15 cm/day, which was the sliding-rate expected from earlier deformation measurements in bore holes made by thermal drilling alone. |
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