Earth Science: Weathering

Biological weathering is a form of physical weathering where plant roots grow into rock cracks, exerting pressure and causing the rock to break apart.

Caves and karst features are created when slightly acidic groundwater reacts with limestone, dissolving the rock chemically.

Acid rain is a form of chemical weathering because it changes the chemical composition of the rock by dissolving minerals. Physical weathering involves mechanical breakdown without changing composition.

Abrasion is the process where rocks collide or rub against each other, causing them to break down physically.

Animals that burrow into the ground physically displace soil and rock, which can lead to the breaking and weathering of rock materials.

Animals cause physical weathering through activities like burrowing, trampling, and digging, which break down rock and soil.

Exfoliation occurs when overlying rock pressure is removed, causing the outer layers of rock to expand and peel away like layers of an onion.

Physical weathering agents like ice (frost wedging), wind (abrasion), and rain (mechanical impact) can break down large boulders over time.

Oxidation is a chemical reaction where oxygen reacts with iron-bearing minerals in rocks, often resulting in a reddish-brown rust color.

Chemical weathering involves a change in the chemical composition of the rock, often resulting in new minerals or a change in appearance, unlike physical weathering which only changes size or shape.

Frost wedging is a classic example of physical weathering, where water expands upon freezing, exerting force that splits the rock.

Temperature changes cause rocks to expand and contract, which can lead to cracking and physical breakdown over time.

Physical weathering is the mechanical breakdown of rock into smaller pieces without changing its chemical composition. Water breaking a boulder is a mechanical process.

Weathering is broadly categorized into two main types: physical (mechanical) and chemical.

Weathering is the general term for the breakdown of rocks and minerals at the Earth's surface by physical and chemical processes.