Sierra and KaDee's Informational Webpage

Sierra and KaDee's Informational Webpage

.. Earth's Changing Surface ..

Topography is the shape of the land. And area's topography may be flat, sloping, hilly, or mountainious. The topography of an area is determinded by the area's elevation, relief, and landforms. Things that have to deal with Topography are Elevation, Relief, and Landforms. Elevation is the height above sea level. Relief is the difference in elevation between the highest and lowest parts of an area. A landform is a feature of topography formed by the process that shape Earth's Surface. Along with Elevation, Relief and Landforms, there are also TYPES of landforms. The three types of landforms are Plains, Mountains and Plateaus. A Plain is a landform that is made up of flat or gently rolling land with low relief. A plain that lies along a seacoast is called a coastal plain. A plain that lies away from the coast is called an interior plain. Mountains are landforms with high elevation and high relief. Mountains usually occur as part of a mountain range. A mountain range is a group of mountains that are closely related in shape, structure, and age. And last but not least the last landform, the Plateaus. A Plateau is a landform that has high elevation and a more or less level surface is called a plateau. A plateau is rarley perfectly smooth on top. And also, streams and rivers may cut into the plateau's surface. To go along with the landforms, and type of landforms, you have to know how to be able to map the latitude and longitude of an area. Latitude is the starting line for measuring distance in degrees north or south of the equator. Longitude on the other hand, is just the opposite. Longitude is the disgance in degrees east or west, but instead of the equator, the prime meridian. There are 360 lines of longitude that run from north to south, meeting at the poles, each line represents one degree of longitude.

Weathering is the process that breaks down rock and other substances at Earths surface. Heat, cold, water, and ice all contribute to weathering. So do the oxygen and carbon dioxide in the atmosphere. Repeated freezing can crack rock apart into smaller pieces. Mechanical Weathering is the type of weathering in which rock is physically broken into smaller pieces. These smaller pieces of rock have the same composition as the rock they came from. Mechanical weathering breaks the rock into pieces by freezing and thawing, heating and cooling, growth of plants, actions of animals, and abrasion. The word abrasion refers to the grinding away of rock by rock particles carried by water, ice, wind, or gravity. Chemical Weathering is the process that breaks down rock through chemical changes. The agents of chemical weathering include water, oxygen, carbon dioxide, living organisms, and acid rain. Chemical weathering produces rock particles that have a different mineral makeup from the rock they came from.

Erosion is the process by which natural forces movie weathered rock and soil from one place to another. A landslide is a very rapid tryped of erosion. Other types of erosion move soil and rock more slowly. Gravity, running water, glaciers, waves, and wind can all cause erosion. The material moved by erosion is sediment. Both weathering and erosion produce sediment. Deposition occurs where the agens of erosion lay down sediment. Deposition changes the shape of the land. Weathering, erosion, and deposition act together in a cycle that wears down and builds up Earth's surface. Gravity is the force that moves rock and other materials downhill. Gravity causes mass movement, any one of several processes that move sediment downhill. The different types of mass movement include landslides, mudslides, slups, and creeps. A landslide is the most destructive kind of mass movement is a landslide, which occurs when rock and soil slide quickly a steep slope. A mudflow is the rapid downhill movement of a mixture of water, rock and soil. The amount of water in a mudflow can be as high as 60 percent. A slump is where a smass of rock and soil suddenly slip down a slope.But, the material in a slump moves down in one large mass. A creep is the very slow downhill movement of rock and soil, it can even occur on gentle slopes. The amount of sediment that a river carries is its load. Gravity and the force of moving water cause the sediment load to move downstream. A river's slope, volume of flow, and the shape of its streambed all affect how fast the river flows and how much sediment it can erode.Glaciers are any large mass of ice that moves slowly over land. There are two kinds of glaciers, valley glaciers and continental glaciers. A valley glacier is a long, narrow glacier that forms when snow and ice build up high in a mountain valley. A continental glacier is a glacier that covers much a continent or large island.