North of the boreal forest is the Arctic tundra ecozone, characterized by low-growing vegetation and few to no trees. Because most of the tundra is underlain by permafrost ,vegetation is not able to put down deep roots, stunting growth.
A wide range of wildlife calls the Canadian Shield home. Lakes and rivers in the south house a variety of fish species including trout , burbot and northern pike. In addition to fish, lakes are often spotted with a mix of waterfowl including wood ducks , Canada geese and American black ducks. Other birds include boreal owls , great horned owls, blue jays and white-throated sparrows , while mammals include caribou , deer , wolves , lynx , moose , black bears and beavers.
Moving north into the tundra, wildlife, like vegetation, becomes increasingly sparse. Animals in the Arctic portion of the Shield include polar bears , Arctic fox ,Arctic hares , snowy owls and rock ptarmigan. The Canadian Shield is rich in natural resources, including minerals, forests and freshwater. Various minerals and precious stones have been mined or continue to be mined on the Shield, including gold , silver , copper , zinc , nickel , iron , uranium and diamonds.
The first modern hard-rock mine in the Canadian Shield, near Madoc, Ontario, opened in after gold was found there. Around the same time, silver was discovered near Cobalt , Ontario, in The town prospered during the silver rush of the early 20th century, before going into decline in the s. While gold mines still operate near Kirkland Lake and Timmins, there are no longer any active mines in Colbalt or Rouyn-Noranda — a reality not uncommon for early mining towns.
Today, the largest concentration of active mines on the Shield — and in the world — is located around Sudbury , Ontario. Metals mined here include copper, nickel, gold andpalladium. Kimberlites — formations where diamonds can be located — are scattered throughout the Shield, with the largest deposit located near Lac de Gras, Northwest Territories ,about km northeast of Yellowknife.
The Canadian Shield also contains iron ore, including deposits near Wawa , Ontario. Today, Saskatchewan is the sole producer of Canadian uranium, primarily from the Cigar Lake area.
Given the prominence of the boreal forest throughout the Canadian Shield, forestry is also a prominent industry. Due to its numerous rivers, the Canadian Shield region produces a significant amount of hydroelectricity.
The Canadian Shield is the traditional territory of several Indigenous peoples. The traditional territory of the Dene and Inuit includes the sections of the Shield now covered by the Northwest Territories and Nunavut. As Europeans began to settle and colonize the country, beavers found in the Shield region became a source for the fur trade see also Exploration. Later, beginning in the mids, railway construction meant blasting throughCanadian Shield rock, exposing valuable minerals in the process.
While the bare rock, thin soils, muskeg and insects of the Shield made living there difficult, the development ofresource-based industries, such as mining and forestry, promoted increased settlement.
The historic mapping of this area was done by Alexander Murray , who, in —52, examined the geology around the Gananoque, Ottawa and St. Lawrence rivers, as well as theperimeter of the Shield from Kingston to Lake Superior. See also Geological Survey of Canada.
His book essentially ignored the eons of geological processes, climatic fluctuations and biophysical changes that had brought these features into existence. It paid scant attention to the particular characteristics of the north country and offered little detail about their influence on Canadian development. We are all now aware of the dynamic qualities of Earth systems and the complex reciprocal relationships that bind humans and nature together. Bringing history and geography together in this way means paying attention to the movements of mountains, the migrations of continents, the waxing and waning of deserts and swamps and the advances and retreats of glaciers, plants and animals.
These processes open certain possibilities for human existence in some places and foreclose them in others. They create the un inhabitable Earth. In other words, humans live in material settings produced by physical processes — and their capacity to amend and transform their surroundings is, and always has been, highly variable. Everywhere, however, lands and lives are shaped by the reciprocal interplay of humans and their environments.
This is the central insight of environmental history and a source of endless fascination. In Canada, ancient and continuing physical processes underpinned the development of a nation across the vast expanse of northern North America. To look backward across this span is to contemplate a world in motion. Much of this movement was propelled by biogeophysical or, broadly, Earth processes. Sometimes they were infinitesimally slow, sometimes they occurred at rates discernible only over the course of a human lifetime and sometimes they were so rapid they were catastrophic.
Humans came late to this place and story, and here and there, and with increasing potency, they added their agency to the forces of nature. Yet the very survival and prosperity of migrants to this world — which was at once old and new — rested on foundations laid down millennia before. Scientific and popular interpretations of the natural world have evolved through time, as have the words we use to describe it.
This means that we need to pay attention to how knowledge is constructed. For example, the terms pre-Cambrian and Canadian Shield trip so easily from 21st-century tongues that it is easy to forget that both are recent coinages. Not until was the name Cambrian applied to the earliest known fossil-bearing strata in Wales and now dated to between and million years ago. Earlier so-called primitive rocks then became pre-Cambrian by implication, but they were also known until as Azoic or lifeless rocks.
Lawrence River. The term was subsequently conferred upon the larger Laurentian Plateau and the Laurentide Ice Sheet that covered it during the Pleistocene glaciation. The Canadian Shield only came into terminological being in the s. Its name combines two ideas. The second was the strong nationalist sentiment of influential Canadian imperialists in the quarter century after Confederation. Radiometric dating and other recent techniques have revealed that parts of it are four billion years old and that the whole is made up of various fragments of material, which erupted from hundreds of now-extinct volcanoes that coalesced and amalgamated between 2.
But such a fine-grained understanding was beyond scientific reach until it became possible, in the latter part of the 20th century, to determine the age of rocks by calibrating decay in their radioactive elements. Scholars were skeptical when the German scientist Alfred Wegener suggested, in , that the continents were in motion. He came to this conclusion in an effort to account for the presence of warm-climate fossils in Arctic rocks and to explain why continental edges seemed to fit together like pieces in a puzzle think of Brazil and West Africa.
Proceeding at between to 1, millimetres a year, these movements are now understood to have caused the formation, breakup and migration of continents over time. Through the millions of years of these movements, the shield formed the nucleus around which geological processes built the North American continent.
It shaped the configuration of the continent, differentiated its topography and moulded its potential or otherwise for settlement and development by humans eons into the future. Two examples suffice to make the point. First, about two billion years ago, the Flin Flon greenstone belt of central Manitoba and east central Saskatchewan was formed by volcanic activity. Approximately 45 kilometres wide and five times as long, it is one of the richest mining areas on the globe.
Since , more than 20 mines have extracted copper, zinc and related metals from this area, and three others have produced gold and silver.
Second, some 1. The resulting crater, the second largest in the world, filled with magma that contained nickel, copper, platinum, gold, palladium, and other metals. The Bay is huge and transportation of resources such as forestry, minerals and other goods and services should be quite simple.
Unfortunately the Bay freezes up for 6 months of the year. So transportation during the winter months is now more limited. The Early Explorers and Fur traders found this out the hard way.
Check out Henry Hudson as one of the early explorers in Canada. As a result of looking for other water sources and also following established fur trading routes, many small cities, towns and settlements have spread throughout this region. Because of this, the population is lower in these areas of Canada because of the climate, landscape as well as the transportation system. Furthermore, the isolation of these areas of population has caused these communities to rely a great deal on the resources that solely surround their community.
It is always good to have a resource at your back door but if that resource runs out, then your future doesn't look very promising. Some of the resources that the Canadian Shield gives to Canadians are:.
Canadians extract copper, gold, nickel , zinc and lead from this area. The immensity of this project alone demonstrates the value of the Shield to the Canadian people and our growing economy. Some of them are turned into newspaper. It is really cool to think that the morning newspaper that you've just read began in the Canadian Shield. Many foreigners view Canada as a place to get back to nature - to get away from the hustle and bustle of the city.
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