The Natural Topography of the Great Lakes / St. Lawrence Region

Introduction North Shore Region Gaspé Peninsula Saguenay-Lac Saint Jean Region Baie Comeau-Manicouagan Region Saint Lawrence Region Appalachian Region Lower Great Lakes Region Kingston-Ottawa/Hull Region Georgian Bay-Laurentides Region Bibliography

The Great Lakes / St. Lawrence region is covered with interesting physical features such as coves, plateaus, terraces, vales, escarpments and drumlins. The topography of the region is the natural history as it helps explain why people settle in certain places and not in others. In addition, many of these features have some touristic interest today such as Mont Tremblant, a large ski mountain found in the Laurentides. Other places arouse curiosity like Logan's Line which is fault line dividing the Appalachians from the St Lawrence Lowlands.

This section is meant to inform the reader on some of the physical features found in the region.

This section is meant to inform the reader on many fascinating features covering the area.The natural topography of the St. Lawrence is important to learn about if one wants to be aware of the area. Each region contains their unique physical features such as the inlets in the North Shore, the fiords of the Saguenay, or the mountains in the Appalachians. Every lake, river or stream has their own story of existence and should be known. Hence, this section has been divided into geographical regions so that it would be easy to visualize the spatial dimensions of the features.

Many inlets exist along the coast.

The Canadian Shield covers the entire North Shore region. Hence, a plateau with an elevation of 500-900 meters above sea level typically drapes the topography of the Shield. The whole region was glaciated, explaining the existence of various lakes and rivers with jumbled drainage patterns. Rivers either flow southward into the Gulf of St. Lawrence or eastward into the Atlantic Ocean. The interior is dominated by spruce forests and the coast is home to most of the inhabitants. The coast is devoid of soils and trees providing an excellent opportunity for a number of inlets to form. Many of these inlets have been developed into well protected harbours for the coastal communities of the region. Typically, the harbours are lined with square, gabled houses sitting on large rock formations.

The Gaspé is also called the "South Shore" by some people.

The last glaciation did not effect the topography very much.

The land rises in terraces parallel to the river.

The Gaspé has also been referred to as the "South Shore" because of its position with respects to the St. Lawrence River . It is approximately 475 km long and varies in width from 45-140 km. The topography of the region is splendid to view with an array of features throughout the peninsula.

The Notre Dame Mountain Range (which is really a plateau in disguise) is located in the eastern end, rising out of the sea for over 500 m. Although the plateau is relatively uniform in shape, there are some outcrops reaching higher elevations such as Mont Jacques Cartier (1277 m), the highest peak in Quebec. These outcrops are also called nunataks, a word which originated from the indigenous peoples of the region. There is some debate as to how much of the region was glaciated. The most popular argument put forth is that most of the area was glaciated, except in places of higher altitude, sparing some of the vegetation. Regardless, ice did not morph the topography very much.

A highway is located on the northern gulf coast shoreline shelf. It is a very narrow highway with high cliffs resting to the left and right. Many streams in the northern shelf go through hard-cut valleys that travel a few km into coves where many gulf fishing villages can be found. The south side rises more gently making it a preferable area for farming. It is also home to the Rocher Percé, an imposing rock with upstanding cliffs just off the coast.

When following the great river along the south shore, which is 22-60 km wide at this point, there is a moderate ascent into the Appalachian Highlands. The land rises as levels cut into the side of the hill always following the river. Hence, the watercourse is similar i.e. small streams follow the contour of the hill, which locate larger streams that flow into the St. Lawrence River. Attenuated thin lakes are common in the interior of the peninsula such as Lake Temiscouata. In addition, two rivers drain southward cutting into the Appalachians: the Madawaska (into St. John River), and Matapedia (into Baie des Chaleurs).

The Shield cuts through the undulating valleys forming the Saguenay River.

The last glaciation has left its mark by leaving awesome fiords.

The Canadian Shield rests 100-1090 m in the region and some higher elevations are found along the banks of the St. Lawrence. A millenium of surface erosion has created an awesome topography of elaborate river valleys. Many people visit the area and marvel at the natural scenery. Complex valleys undulate through the region in a sinuous manner. However, the Shield cuts right across the wave-like valley producing a rift valley engrossed by the Saguenay River, undoubtedly the region's main artery.

The river is tidal until about 105 km away from the St. Lawrence River. In addition, glaciation has pronounced the valley by creating a fiord up to 1500 m wide, 600m deep, and 500m high. These fiords are a major attraction and have been since Cartier visited the region. The fiord splits quickly at La Baie and Chicoutimi. Thence it turns into a tranquil river until it reaches Lac Saint Jean. Lac Saint Jean is 28 km by 43 km and quite shallow. It was much larger in the past; however, the only evidence of its past size are the farms which grow crops on the rich clays. The clays continue for 35 km from the lake until the more common Precambrian rock takes over. Another feature which should be given some attention are the two capes in the fiord past Tadoussac named: Eternity and Trinity. The capes reach a height of 350 m and used to instill fear in the people who passed by them. Although they don't cause the same effect today, they are still an impressive site to see.

Most of the settlements are along the St. Lawrence, but constancy is impossible because of the impermeability at some points of the shore. The settlements are usually located at low areas where tributary valleys cut into the Canadian Shield. Baie Saint Paul is one of the wider valleys and has been inhabited by farmers and fishermen for many years.

The coast is spacious and flat, topped with peat and sandy outwash deposits.

The Manicouagan is one of the largest rivers in the region.

Anticosti Island is part of the St. Lawrence Lowland.

This region is depicted by vast forests and large rivers There are a few small cities scattered including Sept-Iles, Labrador City and Baie Comeau in the back country; but nature prevails. The entire area is dominated by the Shield except for Anticosti island; hence, the shore of the St. Lawrence hits a extensive plateau of Precambrain rock which rises quite abruptly. Basins and ridges dot the area within the Shield and there are no clay belts in the region such as the ones found in the Saguenay-Lac Saint Jean region, making farming a difficult occupation to take up. Nonetheless, the Gulf of St. Lawrence and the St. Lawrence river offers a habitable environment.

The coast is spacious and flat, terraces are low; and the soil is topped with peat and extensive sandy outwash deposits. This phenomena can be attributed to the remnants of glaciation and the recent uplift from the sea. Narrow valleys are filled by rivers which cut into the Shield. The rivers receive water from the numerous lakes which drape the region, again from the period of glaciation. The Manicouagan River is one of the largest rivers in the region and has been used for hydroelectric production. Furthermore, the river is home to a meteoric impact crater which spans 65 km across; and ironically, the hydroelectric facility has produced a lake which follows the contour of the impact crater 55 km across.

Anticosti Island is 225 km long and 56 km wide. It is positioned 45 km from the north shore of the St. Lawrence and is geologically part of the Paleozoic St. Lawrence Lowland. Hence, it is mainly consist of sandstone, limestone and shale strata. Most of the island's coast is surrounded by a high precipice.

The region is squished between to geological borders: the Canadian Shield and the Appalachians.

The St. Lawrence region is a long, narrow strip on both sides of the St. Lawrence River. It is a low plain and is unquestionably the urban and agricultural hub of Quebec. Geologically it is an abrupt boundary between the Canadian Shield on the north and a moderate slope of the Appalachians to the south. For instance, the Canadian Shield is located 46 km to the north and 50 km to the south of Montreal. They meet to the northeast on either side of the St. Lawrence River.

The St. Lawrence region is considered a relatively flat sedimentary basin but glaciation has resulted in diverse terrain including: clay belts, sandy parts, and ranges of poorly drained land. Fertile soils have developed on the clay areas and is ideal for mixed farming. The Monteregian Hills are found eastward from Montreal and rise approximately 11-23 km apart in a line. The highest of the hills is Mount Brome reaching 553 m above sea level. Apple orchards and recreational activities such as skiing can be found on these hills. Some important rivers are also located in the Lowland. The Yamaska, St. François, and Nicolet are some on the south shore rivers while St. Maurice is on the north shore. Furthermore, a drop of 38 m from the Ontario border to Montreal has created a number of rapids like the Lachine Rapid to cite one as an example.

The Appalachians in this region are a set of relatively straight mountain rearranges.

The boundary between the Lowland and the Appalachians is called Logan's Line.

This part of the Appalachians have a consistently straight set of mountain ranges. The ranges starting from the U.S. border include: Border Range, Bunker-Stroke Hills, Sutton Mountains, Richmond Hills, and Brome Hills. The ridges usually have a gentle incline with rounded tops and the valleys are wide and gentle. This has allowed extensive roads and settlements to be built throughout the area despite the Appalachians formidable appearance.There are also many reasonably level erosional surfaces or high plains like the Coaticook and Wottonville. Although some plains rise slowly, some individual mountains rise above the rest such as Mount Meganic rising 1,105 m above sea level. In addition three of Monteregion Hills have penetrated the Appalachian folds and formed separate domes including the Yamaska, Shefford, and Brome.

Numerous courses drain the region and flow in the direction of the St. Lawrence, cutting across the grain of the land. Most of the rivers eroded through ridges and in some cases have produced gorges of considerable depth. St. François is the largest with a number of tributaries including Coaticock. Glaciation deepened and widened some valleys making many lakes such as Aylmer and Memphremagog. Furthermore, the boundary between the Appalachians and the St. Lawrence Lowland is called the Logan's Line which is a fault line; however, unlike the San Andreas Fault, it is not visible.

The Niagara Escarpment was named a World Biosphere Reserve in 1990 by UNESCO.

The region is basically a platform of Paleozoic sedimentary rocks (mainly limestone) overlaying the Canadian Shield gently. One of the most impressive features of the area is the Niagara Escarpment. The escarpment travels from the Niagara River all the way to the Bruce Peninsula. It is a curious physiographic feature on what is generally a flat land. Limestone is exposed in many places especially at the brow, Bruce Peninsula, and Mapitoulin Island with sedementary bedrock never far from the surface. The most pronounced evidence of the escarpment can be found in Georgian Bay where a vertical face of 75 m shoots out into the sky. In fact UNESCO declared the escarpment a World Biosphere Reserve in 1990.

Glaciers have left their mark by depositing a thick layer of drift estimated at 30-200 m, depending on the location. The effect has been extensive till plains, end moraines, and thousands of drumlins. The most famous drumlins are in Peterborough and Guelph.

This region has been called the Mesopotamia of Canada because it is located between two rivers: the Ottawa and St. Lawrence.

The region is the area in between the St. Lawrence River and the Ottawa River. The St. Lawrence declines from an altitude of 74 m at Lake Ontario to 6 m at Montreal, and the Ottawa descends from 46 m at Ottawa to 25 m above Montreal. The average distance between the rivers is 70 km. The western portion of the region has sedimentary rock folding over the Shield. This is also the portion where most of the lakes are found. At times knobs of the Shield extend out of of the surface and Shield bedrock are in beds of streams. Glacial deposits have left drumlins and stony till. The Champlain Sea left badly drained clay levels, sandy terraces, rocky ridges, and broad, level valleys or vales. A fault line runs to the north of the Ottawa River called the Gatineau Hills.

The region is Canadian Shield territory.

The Alquonquin Dome was created by the Shield arching up.

This area is predominantly Shield territory and was heavily glaciated with Precambrain rock knobs and rivers with altered drainage patterns. In addition there are depressions and valleys filled with outwash and clay deposits, and in some instances bogs and lakes have formed. Sand and gravel belts characterize the physical limitations of the glacial lakes. In addition, the topography from place to place changes.

The topography of southern Ontario is primarily a gentle Shield/Paleozoic boundary, whereas the Ottawa Valley and Quebec have a abrupt barrier to the south. The Ottawa River valley is a rift valley i.e. it is surrounded by Mount St. Patrick on the west and Gatineau Hills to the northeast. A physical feature called the Alquonquin Dome is located between the Ottawa River and Georgian Bay reaching a height of 550 m above sea level in some places. In short, the Dome was caused by the Shield arching up. Travelling west of the Mount St. Patrick there are some fault lines with upthrust blocks. These upthrust blocks have formed the Madawaska Highlands. In Quebec, the Laurentian mountain range has many mountains which reach impressive heights for a Shield territory. The highest mountain is Mont Tremblant reaching 968 meters above sea-level, and also happens to be a popular ski hill. The river system is quite important to the area because of their interconnectedness. The most important rivers are the Ottawa, St. Maurice and French. In addition there are hundreds of streams such as the Magnetawan, Gatineau, and the Lievre contributing to the beauty of the region.

• Warkentin, J. (1997). Canada: a regional geography. Scarborough: Prentice Hall Canada.

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