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the grinding and wearing down of rock surfaces by other rock or sand particles

Acid precipitation

precipitation that contains acids due to air pollution


the layer of rock beneath soil

Chemical weathering

the chemical breakdown of rocks and minerals into new substances

Differential weathering

the process by which softer, less weather-resistant rocks wear away, leaving harder, more weather-resistant rocks behind


the removal and transport of material by wind, water, or ice


very small particles of decayed plant and animal material in soil

Ice Wedging

the mechanical weathering process in which water seeps into cracks in rock, freezes, then expands, opening the cracks even wider


the process by which rainwater dissolves and carries away the minerals and nutrients in topsoil

Mechanical weathering

the breakdown of rock into smaller pieces by physical means


a chemical reaction in which an element combines with oxygen to form an oxide

Parent rock

rock that is the source of soil

Residual Soil

soil that remains above the bedrock from which it formed


a loose mixture of small mineral fragments and organic material

Soil conservation

the various methods by which humans take care of the soil


the top layer of soil that generally contains humus

Transported Soil

soil that has been blown or washed away from its parent rock


the breakdown of rock into smaller and smaller pieces by mechanical or chemical means

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