Landforms
Quebec is a landmass covering over 1.5 million square kilometers of land. This large area would understandably be diverse in all geographic factors. Due to this, Quebec has 3 types of landform regions within its borders, the Canadian Shield, Great Lakes-St. Lawrence Lowlands and the Appalachians.
Canadian Shield
The Canadian Shield covers over 90% of Quebec and contains some of the oldest igneous rocks in the world, dating back to the Precambrian period, over 1 billion years ago. This area of Quebec is generally flat and exposed with some mountain ranges such as the Laurentians in southern Quebec, the Otish Mountains in central Quebec and the Torngat Mountains near Ungava Bay in the North. The Canadian Shield has been shaped by glaciers, which explains the glacial sediments of boulders, gravel and sand, and by postglacial seawater and lakes which left thick clay deposits on some parts of the Shield.
Great Lakes-St. Lawrence Lowlands
The Great Lakes-St. Lawrence Lowlands are comparatively tiny in size (about 17 280 square kilometers) in Quebec and are right in between the Canadian Shield and Appalachians. Although small, they contain most of the human population of Quebec. The lowlands are almost entirely flat because of the clay deposits left behind by the Champlain Sea (which once covered all of Montreal). The relief is broken only by the weathered Monteregian Hills, which are composed of entirely different, and much older, rocks.
Appalachians
The Appalachian region of Quebec is comprised of a thin strip of weathered mountains along Quebec's southeast border. The Appalachian mountain chain is actually a long range that runs from north of Alabama in the United States to Newfoundland. In between, it extends into Quebec for about 800 km, from the Monteregians to the Gaspe Peninsula. The rocks of this range are sedimentary, dating back to the Paleozoic era, 250-500 million years ago. In western Quebec, the mean elevation is about 500m, while in the Gaspe Peninsula, the Appalachian peaks are some of the highest in Quebec, surpassing 1000m.