Which processes most directly helps create soil from rocks?

Answer 1

Weathering. Weathering is the breaking down of Earth's rocks, soils and

minerals through direct contact with the planet'satmosphere. Weathering

occurs in situ, or "with no movement", and thus should not be confused with

erosion, which involves the movement of rocks and minerals by agents such

as water, ice, wind, and gravity. In addition, weathering is the effect of

atmospheric exposure to man-made structures and materials.

Two important classifications of weathering processes exist --- physical and

chemical weathering. Mechanical or physical weathering involves the

breakdown of rocks and soils through direct contact with atmospheric

conditions, such as heat, water, ice and pressure. The second classification,

chemical weathering, involves the direct effect of atmospheric chemicals or

biologically produced chemicals (also known as biological weathering) in

the breakdown of rocks, soils and minerals. The materials left over after the

rock breaks down combined with organic material createssoil. The mineral

content of the soil is determined by the parent material, thus a soil derived

from a single rock type can often be deficient in one or more minerals for

good fertility, while a soil weathered from a mix of rock types (as in glacial,

aeolian or alluvial sediments) often makes more fertile soil.