Geo Exam Review - Unit 2 PDF

Unit 2: Interactions in the Physical Environment Plate tectonics is the theory that Earth’s outer shell is made up of individual plates that move. This event can cause earthquakes, volcanos, mountains, and the formation and destruction of the crust. There are three types of plate movement. Divergen...

Unit 2: Interactions in the Physical Environment Plate tectonics is the theory that Earth’s outer shell is made up of individual plates that move. This event can cause earthquakes, volcanos, mountains, and the formation and destruction of the crust. There are three types of plate movement. Divergent boundaries occur when two plates move away from each other. This event happens more commonly along a mid-oceanic ridge. A mid oceanic ridge is a feature created by the spreading of the sea floor where two plates are diverging. The best known example runs through the Atlantic ocean from north to south. Convergent boundaries happen when two plates move towards each other. There are two types of convergence. 1.​ Continental plate meets oceanic plate: The heavier oceanic plate slides underneath a continental plate. This process of one plate sliding under the other is called subduction, where the crust that moves into the earth’s interior is melted and “recycled”, balancing the new crust forming at a divergent plate boundary. 2.​ Continental plate meets continental plate: When two continental plates run into each other, massive layers of rock are folded, broken, and forced upwards by the pressure of the collision. This process has created some of the world’s most important mountain ranges, such as The Himalayas (including Mount Everest). 3.​ Transform: This occurs when two plates move in opposite directions, and plates are neither larger nor smaller. In some occasions, these plates can lock up for many years until a massive release of energy occurs, resulting in earthquakes. —---------------------------------------------------------------------------------------------------------------------------- Rock cycle - There are three forms of rocks: Igneous, Sedimentary, and Metamorphic rocks. Igneous rocks form when magma or lava cools. Most cooling happens out of sight, either at the bottom of the ocean or inside earth’s crust. Sedimentary rocks are created after millions of years of compaction and cementation of loose sediments. The type of sedimentary rock depends on the sediment. Metamorphic rocks are changed versions of igneous, sedimentary, and other metamorphosis. This change occurs when the rocks are exposed to great amounts of heat and pressure. —---------------------------------------------------------------------------------------------------------------------------- Glaciation - Glaciation is the process of ice advancing and covering large areas of land. Although it’s not as powerful of a force as plate tectonics, it’s still important to the formation of the Canadian landforms that we see. The two impacts of glaciation are erosion and deposition. Erosional effects include the removal of materials and changes to drainage patterns. Depositional effects have two types:  1.​ Deposition by meltwater: Fast-moving meltwater can move heavy particles like gravels and rocks. 2.​ Deposition by ice: Two common features formed by ice are till plains, which are small hills and valleys, and moraines, which are deposits of till that form at the edges of a glacier. —---------------------------------------------------------------------------------------------------------------------------- Landform regions of Canada - Canada’s landform regions are divided into three types: Canadian shield: An immense area of ancient, worn down mountains. It is the geologic foundation of Canada, and by far the oldest and largest landform region. -​ It is of Precambian age. -​ It covers more than half of Canada, most of Greenland, and two small areas of the United States. -​ Aboriginal people are the majority of the population on much of the shield. -​ It is one of the most important sources of metallic minerals and diamonds. -​ Most of the shield is not good for farming due to the rock and poor soil. -​ It has a large supply of fresh water -​ Most of its rivers flow into Hudson Bay. -​ Rivers in the south part of the Shield are used to generate hydroelectric power. Lowlands: This area surrounds the Canadian Shield. The three lowlands are: 1.​ Interior Plains: -​ One of the two most important agricultural areas in Canada (along with the GL-SL), accounting for about 75% of the country’s total farm production. -​ The sedimentary rocks beneath the IP are very important to the production of oil and natural gas. -​ This region is the world leader in the production of potash 2.​ Great Lakes St. Lawrence Lowlands: -​ One of the two most important agricultural areas in Canada (along with the IP), accounting for about 75% of the country’s total farm production. -​ Almost 60% of Canadians live in the GL-SL, even though the area makes up only 2% of the country. 3.​ Hudson Bay Arctic Lowlands: -​ Aboriginal people are the majority of the population Highlands: This area surrounds the lowlands. The complex geology of its regions results in valuable mineral resources found in some locations. The three highlands are: 1.​ Western Cordillera 2.​ Innuitian Mountains -​ Canada’s most remote region and has no full time population 3.​ Appalachian Mountains -​ Much older, hence shorter than the IM and WC. -​ Not all of the AM has high elevation. —----------------------------------------------------------------------------------------------------------------------------