| Title | Pingos of the pleistocene Mackenzie River Delta area |
| Download | Download (whole publication) |
| |
| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Mackay, J R |
| Source | Geographical bulletin, No. 18, 1962; by Geographical Branch; Canada Department of Mines and Technical Surveys, Geographical Branch, Geographical Bulletin no. 18, 1962 p. 21-63, https://doi.org/10.4095/331081  Open Access |
| Year | 1962 |
| Publisher | Canada Department of Mines and Technical Surveys |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| Related | This publication is contained in Geographical bulletin, No.
18, 1962 |
| File format | pdf |
| Province | Northwest Territories |
| NTS | 107B/15; 107B/16 |
| Area | Eskimo Lakes |
| Lat/Long WENS | -133.2500 -133.0000 69.2500 68.7500 |
| Subjects | mathematical and computational geology; Nature and Environment; Pleistocene; pingos; permafrost; Mackenzie Delta; Geography |
| Illustrations | photographs; scatter diagrams |
| Released | 1962 11 01 |
| Abstract | Pingos are stable intrapermafrost ice-cored hills. Most were formed over a thousand years ago as an indirect result of the shoaling of lakes by geomorphic and climatic processes. As the lakes gradually
shoaled and lake ice froze to the bottom in winter, an impermeable permafrost cover was formed, ab initio, over the unfrozen saturated sediments beneath. Downward aggradation of the newly formed permafrost cover was predominantly in fine to medium
sands which were not susceptible to extensive ice segregation. Consequently, the pressure of expelled pore water, trapped in a closed system, was relieved by an upward doming of the thinnest part of the overlying permafroc,t cover, which normally
coincided with the deepest part of the lake. Water in the dome froze to form the pingo ice-core. Calculations based on ground and lake temperatures and the nature of the sediments show that pingo growth was slow, probably involving tens of years for
the larger pingos. The large pingos reported in the literature as occurring in the Mackenzie delta are, in fact, not in the modern delta but in Pleistocene sediments to the east. A group of small pingos, which have not been described in detail do,
however, occur in the modern delta. |
| GEOSCAN ID | 331081 |
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