Topic
Ice circle
About: Ice circle is a research topic. Over the lifetime, 60 publications have been published within this topic receiving 1240 citations. The topic is also known as: ice circle.
Papers published on a yearly basis
Papers
TL;DR: The evidence of separate Labradorian and Keewatin centers of radial glacial flow is confined almost wholly to very late Wisconsin time, and indicates that these centers shifted their positions widely even during that short time as discussed by the authors.
Abstract: The evidence of separate Labradorian and Keewatin centers of radial glacial flow is confined almost wholly to very late Wisconsin time, and indicates that these centers shifted their positions widely even during that short time. There is no evidence that these centers ever were the sites of independent glaciers; their importance has been overemphasized. The North American ice sheet, during the Wisconsin maximum, was recognized as a single mass and named the Laurentide ice sheet before the names Labradorian and Keewatin were applied. The Laurentide ice sheet is believed to have originated as mountain glaciers chiefly in the conspicuous highlands of eastern Quebec, Labrador, and Baffin Island. Nourished by moist maritime air masses derived mainly from the south and southeast and moving northward and eastward, these glaciers coalesced into, piedmont glaciers. By continued growth southward and westward toward the principal sources of their nourishment, the piedmonts thickened and spread, burying the highlands in which they had originated. Ultimately they formed a vast ice sheet that extended from the east coast to the Cordillera. Further eastward expansion was prevented by the deep water of the Atlantic, in which the ice broke up and floated away. Glacial-anticyclonic winds are assumed to have been subordinate to cyclonic storms in nourishing the ice sheet. The Labradorian, Keewatin, and other centers of outflow recorded by striae were broad low domes on the surface of the ice and were caused by exceptional concentrations of snowfall. While the ice sheet was shrinking, these domes shifted position.
144 citations
TL;DR: The authors showed that the Keewatin Ice Divide and its precursors represent the centers of an independent, land-based ice sheet that probably existed throughout the period of Wisconsin Glaciation.
Abstract: Patterns of dispersal of distinctive Proterozoic and Paleozoic erratics across terrain formed on Archean and Aphebian crystalline rocks indicate that (1) ice never flowed from Hudson Bay into Keewatin in the region from the Manitoba border (lat 60°N) northward at least to lat 65°N; (2) westward-southwestward flow out of the bay, probably from a Labradorean dispersal center, interfaced with southward- and southeastward-flowing ice from the Keewatin dispersal center somewhere between Nelson River and Churchill; and (3) at least 300 km of dispersal of distinctive erratics observed from the vicinity of the last position of the Keewatin Ice Divide to the present coast of Hudson Bay required considerably more time than the 1,000 to 3,000 yr that the divide has traditionally been thought to have existed. In fact, the Keewatin Ice Divide and its precursors represent the centers of an independent, land-based ice sheet that probably existed throughout the period of Wisconsin Glaciation.
116 citations
TL;DR: It is generally agreed that the Quaternary ice sheets of the Northern Hemisphere were brought about by a cooling of the atmosphere as mentioned in this paper and that a temperature decrease tends to reduce water vapor in the air and...
Abstract: It is generally agreed that the Quaternary ice sheets of the Northern Hemisphere were brought about by a cooling of the atmosphere. A temperature decrease tends to reduce water vapor in the air and...
66 citations
TL;DR: Geomorphological evidence indicates that Donegal was formerly occupied by an ice dome that extended offshore to the west, northwest and north and was confluent with adjacent ice masses to the east and south as mentioned in this paper.
Abstract: Geomorphological evidence indicates that Donegal was formerly occupied by an ice dome that extended offshore to the west, northwest and north and was confluent with adjacent ice masses to the east and south. Erosive warm-based ice over-rode almost all the highest mountains, implying an ice-divide altitude greater than 700 m. Only six peripheral summits escaped glacial modification, implying either that they remained above the ice surface as nunataks or supported a thin cover of protective cold-based ice. Gibbsite, a pre-last glacial weathering product, is preferentially represented on summits that escaped glacial modification. Cosmogenic 10Be exposure ages of 18.6 ± 1.4 to 15.9 ± 1.0 k yr for coastal sites confirm that Donegal ice extended offshore at the last glacial maximum. Reconstruction of the form of the Donegal ice dome suggests a former minimum ice thickness of ∼500 m close to the present coastline in the west and northwest, and ∼400 m near the coast of the Inishowen Peninsula in the north, with the ice extending at least 20 km across the adjacent shelf to the west and northwest. Copyright © 2007 John Wiley & Sons, Ltd.
65 citations
TL;DR: In this paper, massive ground ice, 5-6m in thickness, is exposed within retrogressive thaw flow slides near Sabine Point, Yukon Territory, Canada.
Abstract: Massive ground ice, 5–6 m in thickness, is exposed within retrogressive thaw flow slides near Sabine Point, Yukon Territory. The ice is present near the upper surface of Buckland Till and is overla...
54 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2019 | 1 |
| 2016 | 1 |
| 2014 | 1 |
| 2013 | 1 |
| 2012 | 1 |
| 2011 | 1 |