Geology is the study of the structure and substance of the earth. The earth s physical features have been created by many geological events:

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1 UNIT 1 NOTES : GEOLOGY & THE EARTH S PHYSICAL STRUCTURE GEOLOGY & THE EARTH S PHYSICAL STRUCTURE Geology is the study of the structure and substance of the earth. The earth s physical features have been created by many geological events: Plate, earthquakes,, folding and faulting have all shaped the earth over the past billion years, and continue to change the earth s surface today. Other forces, like ice ( ), wind and running water have also influenced the physical appearance of the planet. GEOLOGICAL ERAS Geologists and geographers have created a timeline to help record major physical changes on earth. The timeline is divided into, and each era describes how the earth s surface was modified. There are major geological eras: 1. Precambrian ( billion million) 2. Paleozoic ( million million) 3. Mesozoic ( million million) 4. Cenozoic ( million present) How can you remember the order of the 4 eras? ACRONYM!!!!!!!!! Example: Precious Parents Make Cookies CONTINENTAL DRIFT THEORY Theory by German geologist and meteorologist stating that 300 million years ago all of the Earth s land masses, which were in constant, collided to form one supercontinent called. About million years ago Pangea broke apart and the continents have drifted apart to their present locations. According to this theory only continents drifted. Diagram: Wegner s Proof of Continental Drift:

2 1. Jigsaw pattern between the shapes of some continents. Example: 2. Fossils of the same plants and animals found on different continents. Example: 3. Structurally similar mountains on both sides of the Atlantic Ocean in NA are similar to the mountains in the northern British Isles and Europe 4. Ice caps once covered southern, India, and South America so these continents were obviously located closer to the South Pole. Most scientists disagreed with Wegner because he could not explain what was powerful enough to move huge continents PLATE TECTONICS THEORY In the 1960 s technology existed to further develop Wegner s theory into the new theory of. The theory states that the Earth s outer shell consists of that move causing, volcanoes, and the formation of new crust. What causes the plate to move? cells are caused by uneven temperature inside the Earth. They are the force that cause plates to move and shift. PLATE MOVEMENTS As plates move away from each other and toward each other the Earth s crust will FOLDING bend rock layers: FAULTING crack the Earth s crust:

3 TWO TYPES OF PLATES: : Underneath oceans, about 4-7 miles thick and thin, but dense. : Underneath continents, about 20 miles thick and Buoyant. Example of Oceanic & Continental: Off the coast of South America along the Peru-Chile trench, the oceanic Nazca Plate is pushing into and being sub ducted under the continental part of the South American Plate. In turn, the overriding South American Plate is being lifted up, creating the towering Andes Mountains. CONVERGING PLATES What happens when an oceanic plate collides with a continental plate? DIVERGING PLATES (HORIZONTAL MOVEMENT) As two plates move apart, magma comes up from the Earth, the sea floor spreads, and a ridge or new crust is formed. TRANSFORMING PLATES (LATERAL MOVEMENT)

4 CONVERGING PLATES (HORIZONTAL MOVEMENT) As two plates collide, one plate descends under the other plate, creating volcanoes. EROSION Erosion is the wearing away of the Earth s surface. The Earth s surface can be worn away by: Wind,, Ice (glaciers) CONTINENTAL DRIFT & PLATE TECTONICS These two theories relate to the physical layout of the earth by creating mountains, volcanoes, trenches, and causing earthquakes. Movement of the Earth s crust has shaped Canada in many ways. Folding, faulting and erosion have formed: - Mountain chains in the east coast ( ) - Mountain chains in the west coast ( ) - Mountain Chains in the north ( ) - The (glaciers eroded the Appalachians) - (oil, gas and coal) - Lakes, rivers, hills and plains (formed by glaciers) LANDFORMS North America is the world s largest continent. It is so large it is a continent of great physical diversity. North America is made up of three distinct types of landforms: WHAT IS THE CANADIAN SHIELD? The Canadian Shield is a large area of rock that forms the core of Canada. The landform region in Canada. Consists mainly of and rock and some rock. WHAT FORCES CONTRIBUTED TO THE FORMATION OF THE SHIELD? -, faulting, and.the features of the Shield are largely a result of the conflict between mountain building forces (folding and faulting) and forces of erosion.

5 -, folding and build up the landscape. - Wind, rain, running water, glaciers, temperature changes and chemical reactions the landscape. - Areas of the Shield developed and disappeared many times. WHY IS THE CANADIAN SHIELD A SIGNIFICANT LAND FORM? Mining companies are attracted to this area because of the presence of (Sudbury, Ontario large deposits of nickel and copper). This creates jobs and minerals are used to manufacture products people use every day all over the world. The tourist industry is very important to the southern parts of the Canadian Shield because of all the, and. Plentiful water makes the Shield an excellent source of generated energy. LOWLANDS Areas of low elevation containing plains and hills. There are 4 different lowland areas in Canada: Great Lakes St. Lawrence Lowlands 3. Hudson Bay Arctic Lowlands (not shown on the map on pg 93) 4. DIFFERENTIAL EROSION - Occurs when soft rock erodes more quickly and easily than hard sedimentary rock. - Created escarpments. - In the Interior Plains the land slopes from to. - The Niagara Escarpment in the Great Lakes St. Lawrence Lowlands. HIGHLANDS Areas of high elevation containing mountains and plateaus. There are different highland areas in Canada: - : Sedimentary rock was uplifted and folded at the end of the Paleozoic era when North America collided with Europe and northern Africa. - : Formed in the middle of the Mesozoic era the North American plate moved northward. - : The heavier Pacific plate forced under the lighter North American plate causing folding, faulting and volcanic activity

6 INTERIOR PLAINS AND LOWLANDS - Consists mainly of rock. - Part of the sedimentary rock consists of coral reefs that formed when the plains were covered with shallow seas during the era. - Today they contain and (Alberta and Saskatchewan). - Mineral deposits (potash and coal) were left in the dried out sea beds from the Mesozoic era (Saskatchewan). - Were once covered by. - The melted leaving behind large lakes. - Later, the land rose (rebound affect) causing most of the water to drain into the ocean. Small portions of the ancient lakes exist today: - Lake Winnipeg, Lake Manitoba, Lake Winnipegosis, and Cedar Lake. - Soil that developed is deep and fertile suitable for agriculture. GREAT LAKES AND ST.LAWRENCE LOWLANDS - Consists mainly of sedimentary rock. - Excellent and warm climates suitable for. - The Great lakes are located in basins that were gouged out by glaciers. - St. Lawrence Lowlands is a rift valley formed from. HUDSON BAY ARCTIC LOWLANDS - Consists mainly of sedimentary rock which rests on ancient Shield rock. HUDSON BAY LOWLANDS - Used to be covered by water from Hudson Bay. - Now, flat low,. ARCTIC LOWLANDS - Land is most of the year. - Rock contains lignite (form of coal), oil and natural gas deposits COSTAL LOWLANDS - Consists mainly of sedimentary rock. - Mineral deposits such as,, and. - Lower elevation than the Interior plains - Rich and lots of rainfall productive agriculture. GLACIATION IN CANADA - A is a slow moving sheet of which grows or melts over time. - Glaciers covered Canada as recently as years ago and have greatly shaped Canada s landscape. - and were created when glaciers melted. - Large, and were moved and deposited by the ice. - Small areas of glaciers can still be found. (Columbia ice fields) & in the Arctic and Antarctic. - During the last ice age ( years ago) different types of glaciers affected Canada s landforms.

7 Alpine Glaciers: - Helped erode and created large below. Continental Glaciers: - Covered the parts of Canada. - the land and deposited rich material that became fertile prairie. WEATHER AND CLIMATE Weather The expressions of the atmospheric conditions such as temperature, precipitation, humidity, wind, cloud cover and air pressure. Climate The pattern of the atmospheric conditions such as temperature, precipitation, humidity, wind, cloud cover and air pressure. HOW WEATHER AND CLIMATE AFFECT OUR LIVES Weather Climate CANADA S CLIMATE Varies greatly from coast to coast for the following reasons: - Canada extends a great distance to. - Different produce different climate conditions. - and regions have different climates. - and systems move weather conditions from one part of the country to another.

8 CLIMATE Continental Climate Maritime Climate ex: Winnipeg, Regina, Edmonton ex: Vancouver, St. Johns, Halifax AIR MASS - Large parcels of air which move and create. - Air masses originating over the water usually hold lots of and produce (coastal locations tend to receive more precipitation). - Air masses originating over land are usually (continental locations receive less precipitation). Types of Air Masses (Fig pg 125): mp = maritime polar mt = maritime tropical cp = continental polar ct = continental tropical ca = continental arctic FRONT Leading edge of an air mass where warm and cold air masses meet. The leading edge of a cold air mass is called a : - Cold fronts occur when heavy cold air pushes lighter warm air upwards. - Temperatures drop and rain, snow, sleet, and hail can occur. - Clouds form and usually grow into.

9 The leading edge of a warm air mass is called a : - Warm air rises up and over the cold air. - Some of the warm air mixes with the cold air and condenses to form. - Can rain or drizzle for many hours. PREVAILING WINDS - Prevailing winds are created by air. - (Fig 11-9, 11-10) - L = low pressure (hot air rising away from the earth) - H = high pressure (cool air falling towards the earth) - As air moves from high pressure areas to low pressure areas (convection) it creates wind winds. - Prevailing winds are winds that are most commonly found in an area. - Example: - Over most of Canada the prevailing winds are (blow from west to east). JET STREAM - A current of fast-moving air that is located high in the atmosphere above the boundary between cold, dry polar air and, tropical air. - It moves from to all the way around the earth. - It changes speed and position with the seasons. Moves in the winter bringing cold arctic air south. Moves in the summer bringing warm southern air to the north. HOW DOES LATITUDE AFFECT CLIMATE? - Temperatures are at the equator. - The equator receives the more sunlight than anywhere else on Earth because the equator is closer to the sun (sphere shaped Earth). - Sun s rays are more at the equator. - Temperatures as you get further from the equator and closer to the poles. - It is cooler toward the poles because the sun s rays are spread over a wider area and the poles are further away from the sun (sphere shaped Earth). MODERATING AFFECT Water up and down more slowly than land. In the summer, - a lake remains than the land surrounding it.

10 - winds blowing across the water will the surrounding area. In the winter, - A lake gives up its more slowly than the land surrounding it. - Winds blowing across the water will the surrounding area. HOW DO OCEAN CURRENTS AFFECT CLIMATE? The temperature of an ocean current affects the temperature of the air that passes over it. - cool the air of coastal region. - heats the air of the coastal region. How do prevailing winds affect the movement of air masses? - Prevailing winds move air masses in the direction they blow. - Example: Prevailing move air masses from the west to the east. How does the polar jet stream influence the movement of air masses? Influences movement of air masses: - In the jet stream moves south allowing arctic air to settle over Canada and move into the United States. - In the jet stream moves north allowing warm air from the Gulf of Mexico to travel further into Canada. 3 CONDITIONS THAT CAUSE AIR TO RISE 1. Cross and area of high elevation. precipitation: Results when warm moist air from the ocean is forced to rise by large mountains. - As air rises it cools, moisture in the air condenses and clouds and precipitation result on the windward side of the mountain - The leeward side receives very little precipitation - This is common in. 2. After absorbing heat from the earth s surface. precipitation: Results from the heating of the earth's surface that causes air to rise rapidly. - As the air rises, it cools and moisture condenses into clouds and precipitation result - This type of precipitation is common in the. 3. A cooler denser air mass below forces air up. precipitation: Results when a warm front meets a cold front - The warmer air mass is forced up over the cool air - As it rises the warm air cools, moisture in the air condenses, clouds and precipitation result

11 SOIL - This precipitation is common in. Geographers define soil as the surface layer of earth Although soils differ greatly from region to region. All soils are composed of 4 parts: Soil is created when (known as Parent Material) are broken down (weathered) into small particles and mixed with other materials. Different types of weathered rocks produce different kinds of soil. Some of the most fertile soils in Canada are found on the prairies and in the river valleys (ex: Okanagan Valley, BC). The least developed soils are found in the, and. These soils are too thin to support diverse natural vegetation or agriculture. LEACHING - Occurs in areas of high. - movement of water through soil. - Water dissolves and. - Excessive leaching results in poor, thin topsoil. Diagram page 141: CALCIFICATION - Occurs in areas of precipitation. - movement of water through soil. - Water evaporates and leaves behind minerals. - calcification results in mineral deposits that are poisonous to plants. Diagram page141

12 NATURAL VEGITATION Plants that would grow in an area in the absence of human influence Canada s natural vegetation regions: -. - West coast forest -. - Boreal and Taiga forest Deciduous forest Transition Zone: An area where the characteristics of one region gradually change into those of another.