Grade 9 Geography Term 3 Test Scope

A complete set of vocabulary flashcards covering physical, chemical, and biological weathering, erosion, deposition, landforms, and human impact on soil for the Grade 9 Geography test.

Physical Weathering

The mechanical process that breaks down rocks into smaller pieces without changing their chemical composition.

Freeze and Thaw Method

A type of physical weathering where water enters rock cracks, freezes, expands, and eventually causes the rock to break apart.

Expansion and Contraction

A physical weathering process where repeated heating during the day and cooling at night cause rocks to expand and contract, leading to stress and cracking.

Granular Disintegration

A form of physical weathering where individual mineral grains fall away from a rock because different minerals expand and contract at different rates.

Chemical Weathering

The process that breaks down rocks through chemical reactions that change their mineral composition.

Oxidation

A chemical weathering process occurring when oxygen reacts with minerals in rock, such as iron, creating rust and weakening the rock.

Hydrolysis

A chemical weathering process where minerals in rock chemically react with water to form new minerals and soluble substances.

Acid Rain

Rainfall containing acids formed from atmospheric pollution that reacts with minerals in rocks, accelerating chemical weathering.

Biological Weathering

The breakdown of rocks caused by the activities of living organisms, such as plants, animals, and microorganisms.

Weathering Caused by Animals

A form of biological weathering where burrowing animals dig into rock fissures, exposing fresh surfaces to air and water and physically breaking rock apart.

Weathering Caused by Plants

A form of biological weathering where plant roots grow into rock cracks and exert pressure as they expand, forcing the rock apart.

Erosion

The removal and transport of rock particles, soil, and dissolved materials from one place to another by agents such as water, wind, or ice.

Deposition

The process by which eroded sediment, soil, and rock particles are dropped or laid down in a new location as energy decreases.

Erosion and Deposition on Beaches, Glaciers, and Cliffs

Geomorphic processes where wave action, glacial movement, and gravity break down and shape cliffs, form beaches from deposited sand, and carve glacial valleys.

Agricultural Contribution to Soil Erosion

Farming practices such as overgrazing, plowing, and clearing natural vegetation that expose topsoil to wind and water, causing accelerated soil loss.