The Role of Diastrophism in the Regimen of Glaciers in the st. Elias District, Alaska
Abstract The “earthquake avalanche” theory was invoked by Tarr and Martin in 1914 to explain anomalous turn-of-the-century glacier advances in Yakutat Bay, Alaska. The concept was given credence by the fact that this bay was the epicenter of a series of severe earth tremors in the autumn of 1899. In...
| Published in: | Journal of Glaciology |
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| Main Author: | |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Cambridge University Press (CUP)
1958
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| Online Access: | http://dx.doi.org/10.1017/s0022143000023959 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022143000023959 |
| Summary: | Abstract The “earthquake avalanche” theory was invoked by Tarr and Martin in 1914 to explain anomalous turn-of-the-century glacier advances in Yakutat Bay, Alaska. The concept was given credence by the fact that this bay was the epicenter of a series of severe earth tremors in the autumn of 1899. In considering alternative explanations, Tarr and Martin dismissed a record of excessive precipitation along this coast in the late 1870’s and 1880’s in the belief that the measurements were in error due to a “peculiarity in the method of measurement”. The disputed data are now known to be consistent with observed and inferred regional climatological trends in the latter half of the 19th century. The case for the climatological control of glacier fluctuations in the St. Elias District is therefore reassessed. Reference is made to new and extensive evidence from other districts in southern Alaska where the earthquake influence was negligible. It is concluded that the fluctuation pattern in the Yakutat area was not unique and that the diastrophism to which these particular resurgences have been attributed was actually but a supplemental and generally minor factor in a widespread set of glacial advances initiated by climatological causes. The theoretical implications of changes in load conditioned by climatological parameters over the broad névés of the St. Elias Mountains are briefly discussed with respect to orogenic activity in this tectonically sensitive region. |
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