Canadian Shield

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Canadian Shield

or

Laurentian Plateau

(lôrĕn`chən), U-shaped region of ancient rock, the nucleus of North America, stretching N from the Great Lakes to the Arctic Ocean. Covering more than half of Canada, it also includes most of Greenland and extends into the United States as the Adirondack Mts. and the Superior Highlands. The first part of North America to be permanently elevated above sea level, it has remained almost wholly untouched by successive encroachments of the sea upon the continent. It is the earth's greatest area of exposed Archaean-age rock; the metamorphic rocks of which it is largely composed were probably formed in the Precambrian. Repeatedly uplifted and eroded, it is today an area of low relief (c.1,000–2,000 ft/305–610 m above sea level) with a few monadnocks and low mountain ranges (including the Torngat and Laurentian Mts.) probably eroded from the plateau during the Cenozoic era. During the Pleistocene epoch, continental ice sheets depressed the land surface (see Hudson BayHudson Bay,
inland sea of North America, c.475,000 sq mi (1,230,000 sq km), c.850 mi (1,370 km) long and c.650 mi (1,050 km) wide, E central Canada. Hudson Bay and James Bay (its southern extension) and all their islands border Nunavut Territory, Manitoba, Ontario, and Quebec.
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), scooped out thousands of lake basins, and carried away much of the region's soil. Drainage is generally very poor on the shield. The southern part of the shield has thick forests while the north is covered with tundra. The region is largely undeveloped but has great water-power potential and is a source of minerals, timber, and fur-bearing animals.

Canadian Shield

[kə′nād·ē·ən ′shēld]
(geology)

Canadian Shield

(in Canada) the wide area of Precambrian rock extending west from the Labrador coast to the basin of the Mackenzie and north from the Great Lakes to Hudson Bay and the Arctic: rich in minerals
References in periodicals archive ?
Isotope geochemistry was the key to determining that the hydrocarbon and hydrogen gases deep in Precambrian Shield rocks are produced not by conventional mechanisms but by abiogenic reactions.
Geologists call it the largest craton in the world, and much of Canada's mineral wealth - including gold, nickel, copper, zinc, and iron - comes from the Precambrian Shield.
Exploration is still in its early stages but sufficient evidence has been brought forth to suggest that the Slave Structural Province, by virtue of its old Archean age (cratonisation greater than 2,500 million years) and forming, as it does, part of the largest Precambrian Shield in the world, has the right geological framework to host diamond-bearing kimberlites.
Also, there are many occurences of lead/zinc and barite at the base of the coastal Mesozoic sediments where they overlap onto the Precambrian shield.
The Company continues to concentrate its efforts as well on expanding its pilot operations into production operations on its placer gold project on the C Zone within its 136,500 acres (213 square miles) in eastern Bolivia's Precambrian Shield.
The Company continues to concentrate its efforts as well on its placer gold project on the C Zone, within its 136,500 acres (213 square miles) in eastern Bolivia's Precambrian Shield.
The Company is currently focusing its efforts on developing its mining rights on its A Zone "Buen Futuro" gold and copper project, as well as its gold project on the C Zone, within its 136,500 acres (213 square miles) in eastern Bolivia's Precambrian Shield.
The Company is currently focusing its efforts on developing its mining rights on its A Zone "Buen Futuro" gold and copper project, as well as its gold project on the B & C Zones, within its 136,500 acres (213 square miles) in eastern Bolivia's Precambrian Shield.