Mass wasting occurs on both terrestrial and submarine slopes and has been observed on Earth, Mars, Venus and Jupiter. Viva Differences. What Is Weathering? Many mass movements happen when a slope becomes steeper than the angle of repose. Intro to Physical Geography: geomorphology, weathering, mass movement You should be able to: 1 List and describe the processes that contribute to landform denudation 2 Define and compare physical weathering and chemical weathering 3 Describe some of the physical weathering processes 4 Describe some of the chemical weathering processes 5 List factors which control the weathering rate 6 Define mass movement as a process of denudation A.
Landform development geomorphology 1. Weathering -- disintegration of rock 1. Abrasion - When pebbles grind along the river bank and bed in a sand-papering effect. Attrition - When rocks that the river is carrying knock against each other. They break apart to become smaller and more rounded. Solution - When the water dissolves certain types of rocks, eg limestone. Weathering and mass movement As the river flows, it erodes the land creating a valley with steep sides called a v-shaped valley.
There are three types of weathering: Mechanical — physical changes causes rocks to break down, for example, a change in temperature from day to night causes rock to expand and contract and break up eg onion skin weathering.
Or, changes in temperature cause water to freeze and expand, melt and contract leading to freeze-thaw weathering. Chemical — rainwater is slightly acidic and over time this wears away the rock. Biological - occurs when plants and animals wear away rocks, for example, roots growing in cracks in the rock or animals such as rabbits burrowing into rock.
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