GLACIAL BOULDERS ON THE ARCTIC COAST OF ALASKA*
A LTHOUGH it seems definitely established that the Pleistocene glaciers of Alaska did not extend north beyond the northern foothills of the Brooks Range, except for small tongues that occupied the upper reaches of some of the major river valleys without reaching the coast (Flint, 1947, p. 222), ther...
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| Format: | Text |
| Language: | English |
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| Online Access: | http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.525.582 http://pubs.aina.ucalgary.ca/arctic/Arctic11-2-70.pdf |
| Summary: | A LTHOUGH it seems definitely established that the Pleistocene glaciers of Alaska did not extend north beyond the northern foothills of the Brooks Range, except for small tongues that occupied the upper reaches of some of the major river valleys without reaching the coast (Flint, 1947, p. 222), there are scattered references in the literature to glacial boulders found along and close to the shore of the Arctic Ocean (Smith and Mertie, 1930, pp. 241-2; Stefansson, 1910, pp. 460-1; Brooks, 1906, p. 261). The only published comprehensive summary of these scattered observations is that by Leffingwell (1919, pp. 142-9, 175, 177) who, after summing up earlier observations, describes a deposit of till-like material under the name of the “Flaxman formation”. His discussion of this formation can be briefly sum-marized as follows. At Flaxman Island, the type locality, the formation consists of till com-posed of clay, boulders, gravel, and sand in proportions similar to those found in other tills. The Flaxman boulders are of many types: quartzites of several kinds, greenstone, granite, limestone, diabase, quartz diabase, and |
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