Weathering is the name given to the process by which rocks are broken down to form soils. Rocks and geological sediments are the main parent materials of soils (the materials from which soils have formed). There are three main types of weathering; physical, chemical and biological. …

The important agents of mechanical weathering are: The decrease in pressure that results from removal of overlying rock. Freezing and thawing of water in cracks in the rock. Formation of salt crystals within the rock.

Weathering is important because it: Produces unconsolidated material (parent material) from which soil is formed. Results in the formation of secondary minerals, the most important group being the clay minerals. smaller rocks are weathered to the minerals that make up the rocks.

Mechanical weathering is weathering caused by the breaking down of rocks by physical force without any change in the chemical nature of the rocks. Mechanical weathering is usually caused by extreme hot and cold temperatures. Water seeps into cracks in rocks, freezes, and expands, causing further breakdown of rocks.

Why is weathering important? a) It breaks down rocks to form soils. b) It breaks up minerals in rocks to release important nutrients into the soil. The breaking down of the rock materials occurs in place with little or no movement.

Deposition is the geological process in which sediments, soil and rocks are added to a landform or landmass. Wind, ice, water, and gravity transport previously weathered surface material, which, at the loss of enough kinetic energy in the fluid, is deposited, building up layers of sediment.

Aside from desertification, there is no doubt that human activities are a major cause of soil erosion in general. Construction of roads and buildings, logging, mining, and agricultural production have resulted in large amounts of soil erosion in the U.S. and around the world.

Different Soil Erosion Causes

• Sheet erosion by water;
• Wind erosion;
• Rill erosion – happens with heavy rains and usually creates smalls rills over hillsides;
• Gully erosion – when water runoff removes soil along drainage lines.
• Ephemeral erosion that occurs in natural depressions.

The agents of soil erosion are the same as the agents of all types of erosion: water, wind, ice, or gravity.

Ice Erosion

Wind by itself is the weakest agent of erosion.