The Land
Southwest Anderson Plain
(briefly)
(Part I)
by
Jean-Luc Pilon
NOGAP Archaeologist
Canadian Museum of Civilization

Research Area

We carried out our work in the uplands area which forms the headwaters of a number of streams draining the southwest portion of the Anderson Plain, immediately east of the Mackenzie Delta. However, we also conducted surveys in the Peel Plain Uplands to the south and in the Inuvik area to the west.

Physiography

The southwest Anderson Plain is comprised of three physiographic sectors, with the main one being the Hyndman Lake Uplands. That area encompasses the headwater lakes of streams flowing in all cardinal directions. It is characterised by a hilly terrain with well-defined glacial melt-water channels. The Inuvik-Anderson River Plains is a physiographic sector which lies to the north and west of the Hyndman Lake Uplands and is marked by lower glacio-fluvial features. The last major physiographic sector lies along the Mackenzie River and is a low plain, part of the Peel Plain Lowlands.

Evolution of the Landscape

Late Pleistocene ice covered virtually all the southwest Anderson Plain with a last advance over the area some 13,000 years ago. At that time, ice-free areas were occupied by interconnected glacial lakes which drained into the Kugaluk River system. These lakes formed distinct high elevation benches. Lower benches, usually a few meters above the present lake levels may indicate the irregularity of the drainage of these lakes and the effects of isostatic rebound.

Deglaciation occurred very rapidly in the northwestern portion of the Laurentide Ice Sheet which may have been comparatively thin over the region such that melting occurred downward and thus disappeared over a large area quite rapidly rather than melting inward toward an ice centre. In any event, deglaciation took place between approximately 11,000 and 9,000 years ago. The region's landscape thus assumed its present appearance by at least 9,000 years ago.

Studies of fossil pollen in the Eskimo Lakes and in the northern Mackenzie Delta indicate that revegetation happened quickly. Between 10,500 and 9,000 years ago, dwarf birch was the main species. Between 9,000 and 5,500 years ago, spruce, poplar and later juniper were added. Modern vegetation patterns had implanted themselves in the study area by 5,000 years ago.