Climate in Earth History Studies in Geophysics (1982) / Chapter Skim
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6 Continental Glaciation through Geologic Time
6 Continental Glaciation through Geologic Time
Pages 77-82
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From page 77... ...
NATURE OF THE GLACIAL RECORD Glaciers scour into hard rock and cut characteristic landforms such as U shaped valleys, stoss and lee shapes, and roches moutonnees. In addition, the surfaces of these landforms are scratched by stones frozen fast within the ice as the glacier inexorably scrapes across bedrock.
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From page 78... ...
Tertiary huge continental ice sheets, smaller ice caps, Piedmont ice sheets or aprons, and alpine glaciers confined to mountain ranges. Where glaciers reach the sea, icebergs calve and float away, carrying within them clots of debris including large boulders.
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From page 79... ...
In examining the record of ancient ice ages, it may be difficult to distinguish between continental ice sheets, ice caps, and mountain glaciers. Tectonic reconstructions may indicate that plate convergence took place near the preserved strata, and so we may infer with confidence that alpine glaciers prevailed.
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From page 80... ...
alla drifted across the smith poles, glacial centers roughly followed the migrating poles. Despite incompletenes of paleomagnetic data and controversy concerning interpretation, recently published apparent wander paths (Figure 6.2)
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From page 81... ...
In the late Precambrian, however, a body of evidence from paleomagnetism suggests that continental glaciation occurred at low latitudes (Tarling, 1974, hfcWilliams and McElhinny, 1980) , for which as yet no satisfactory explanation has come forth.
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From page 82... ...
. Late Precambrian gdacial climate and the Earthsobliquity, Geal.
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