First approximation of the volume of ground ice, Richards Island, Pleistocene Mackenzie Delta, Northwest Territories, Canada

1980 ◽  
Vol 17 (4) ◽  
pp. 509-516 ◽  
Author(s):  
W. H. Pollard ◽  
H. M. French

Using data contained in the Mackenzie Valley Geotechnical Data Bank together with data derived from morphometric analyses of topographic maps and air photographs, the volume of ground ice present in the upper 10 m of Richards Island is calculated to be 10.27 km3. Pore and segregated ice constitute over 80% of the total ice volume. Wedge ice constitutes between 12 and 16% of total ice volume in the upper 4.5 m, and approximately 36% of all excess ice. In the upper 1–2 m, wedge ice may exceed 50% of earth materials. Pingo ice is insignificant in terms of its contribution to total ice volumes. Excess ice constitutes 14% of the upper 10 m of permafrost; it follows that thawing of this layer of permafrost may lead to an average subsidence of 1.4 m.The results of this study are probably typical of other areas of the Pleistocene Mackenzie delta. There is also general agreement with data obtained from arctic Alaska.


1993 ◽  
Vol 30 (3) ◽  
pp. 506-514 ◽  
Author(s):  
E.G. Hivon ◽  
D.C. Sego

Saline permafrost has a detrimental impact on the performance of foundations. Increased pore-water salinity decreases the strength and increases the deformation susceptibility of permafrost and foundations installed in permafrost. A data base of the distribution of saline permafrost in the Northwest Territories shows high pore-water salinities beneath coastal communities and at locations along the upper Mackenzie Valley and within the Mackenzie Delta. Salinity of inland sites is usually low. High salinities are usually associated with ice-poor materials and are linked with previous marine submergence associated with glacial events. Key words : permafrost, saline distribution, measurements, Quaternary geology.


1994 ◽  
Vol 59 (2) ◽  
pp. 316-334 ◽  
Author(s):  
Genevieve M. LeMoine

A series of experiments making and using bone and antler tools show that functional identifications of these tools can be made with confidence in some circumstances. Using principles from the field of tribology, the experiments demonstrate that different uses leave different microscopic traces on bone and antler. They also show that when the materials used are similar, the wear produced will be similar. In particular, wet materials, including snow, ice, wet hide, and wet antler all produce nearly identical microscopic patterns. Other groups of similar materials, such as bone, antler, and wood, or fish scales and hair, present the same problem. Although differences can be detected, these may not be preserved on archaeological tool specimens. Application of the experimental results to bone and antler tools from the Mackenzie Delta illustrates that functional identifications of tools can be made with confidence, despite the problem of similar microscopic patterns, when other lines of evidence (ethnographic and historical accounts, distribution of wear) are taken into account. When such information is lacking, functional identifications are more difficult and must be made with more caution.


1997 ◽  
Vol 29 (4) ◽  
pp. 430 ◽  
Author(s):  
Murray B. Hay ◽  
John P. Smol ◽  
Kathryn J. Pipke ◽  
Lance F. W. Lesack

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