Origin of Debris-Covered Icebergs and Mode of Flow of Ice Into “Miller Lake”, Martin River Glacier, Alaska

Abstract During the summer of 1963. a drift-veneered mass of ice suddenly emerged at the surface of “Miller Lake”, art ice-walled lake at the terminus of the Martin River Glacier, Alaska. Subsequent fathometer traverses, together with the fact that the ice was not at the pressure melting point, reve...

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Bibliographic Details
Published in:Journal of Glaciology
Main Authors: Reid, John R., Callender, Edward
Format: Article in Journal/Newspaper
Language:English
Published: Cambridge University Press (CUP) 1965
Subjects:
Online Access:http://dx.doi.org/10.1017/s0022143000018475
https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000018475
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Summary:Abstract During the summer of 1963. a drift-veneered mass of ice suddenly emerged at the surface of “Miller Lake”, art ice-walled lake at the terminus of the Martin River Glacier, Alaska. Subsequent fathometer traverses, together with the fact that the ice was not at the pressure melting point, revealed that it had been derived from a hole approximately 40 m. below the surface of the lake. There are numerous large debris-covered icebergs in the lake and presumably at least some are formed in this manner. Others are derived through differential ablation of projections of the glacier into the lake. Only the small icebergs are formed through calving. The interpretation of the mechanism of release of ice from the bottom of the lake, and the observation and interpretation of a rising ice-cored island in the same lake suggest that the ice on the bottom is deforming plastically and that it is undergoing compressive flow. Much of the movement may be along shear planes actually found in icebergs derived from the bottom of the lake.