erosion

• Erosion is the wearing away of the land surface and removal of sediment by means of transport.
• Agents of erosion include rivers, marine processes, and the wind (aeolian action).
• U shaped valleys are formed by glaciers which widen, deepen and straighten pre-existing river valleys.
• Roche moutonees are scratches on the rock to show the direction of glaciers.
• Rivers are a major agent of erosion, with processes such as abrasion, hydraulic action, attrition, and solution.
• Abrasion in rivers is when material is carried along by the river in contact with banks and river beds, decreasing the size of sediment.
• Hydraulic action in rivers is the force of the river on the bank and river bed.
• Attrition in rivers is when sediment collides with each other and the impact changes the shape of the particles from sharp and angular to smooth and round.
• Solution in rivers is when acidic river water dissolves the minerals from the banks and river bed, especially carbonates like calcite.
• Abrasion is the process where material that has been plucked by a glacier wears the material beneath the glacier.
• No attrition is the process where the rocks within a glacier do not collide, staying the same shape.
• Wind attrition is the process where grains of sand are picked up and carried by the wind, colliding with each other.
• Glaciers and ice sheets cause plucking, abrasion, and no attrition.
• Deflation is the process where the wind takes the finer particles away from the coarser grains, causing the surface to sink and become concentrated.
• Plucking is the process where the pressure from a moving glacier causes cracks in a rocky object, causing the rock to break in the direction of least pressure because the ice freezes in the cracks.
• Wind abrasion is the process where wind crashes sand grains into rock, wearing it down.
• Glaciated landscapes are the result of glaciers and ice sheets.
• Marine processes are also a major agent of erosion, with processes such as hydraulic action, attrition, abrasion, and solution.
• Hydraulic action in marine processes is the force of the sea on the shore and seabed.
• Attrition in marine processes is when sediment collides with each other and the impact changes the shape of the particles from sharp and angular to smooth and round.
• Abrasion in marine processes is when material is carried along by the sea in contact with the shore and seabed, decreasing the size of sediment.
• Solution in marine processes is when acidic sea water dissolves the minerals from the shore and seabed, especially carbonates like calcite.
• The wind, also known as aeolian action, is a major agent of erosion, with processes such as abrasion, hydraulic action, attrition, and solution.