28. The Formation of Landscapes and Landforms

Photo 51: Landscape at Abraham Lake, Alberta. 2011-05-18

Landscapes and Landforms

A landscape is a combination of many landforms. Landforms are the individual defining features of a landscape. Landforms are formed through folding, faulting, tilting, and warping of the earth’s crust, often due to earthquakes and volcanic activity. The results of these forces are called primary landforms. Weathering and erosion shape landforms in defining ways, resulting in what is called secondary landforms. Photo 51 shows a beautiful landscape, filled with primary landforms, the Rocky Mountains, as well as a secondary landform, the Lake. Although lakes and streams are often naturally created secondary landforms, Abraham Lake is partially artificially created by humans.

Degradation and aggradation.

To create secondary landforms, some areas are worn and weathered away in the denudation or degradation process. In other areas, sediment is added to the existing strata in the aggradation process. Flood plains and river deltas are good examples of aggradational areas. Erosion is an important degradational force that defines a wide variety of processes: running water (see posts on Units 31, 32, 34), glaciers (see posts on Units 36, 37), wind (see post on Unit 40), coastal waves, and chemical dissolution (see Karst post on Unit 35). Buffalo Jump in the Albertan Badlands (photo 52) is the place where North-American natives used to chase buffalos of a steep cliff.  Photo 52 shows very clear water erosion in these soft sedimentary rock layers.

Photo 52: Obvious signs of water erosion, creating art-like nature, at Buffalo Jump, Alberta. 2011-05-12