Glencoe Sv7-Unit 7, Ch 8 Voc

Front 1

chemical weathering

Back 1

the type of weathering that occurs when air, water, and other substances react with minerals in rocks

Front 2

humus

Back 2

dark-colored, decayed organic matter in soil that serves as a nutrient source for plants, promotes good soil structure, and helps soil hold water

Front 3

weathering

Back 3

mechanical or chemical process that breaks down rocks into smaller and smaller fragments

Front 4

horizon

Back 4

a soil layer in the soil profile; most areas have three--the A horizon (top soil layer), the B horizon (middle soil layer), and the C horizon (bottom layer)

Front 5

ice wedging

Back 5

mechanical weathering process that occurs when water freezes in the cracks of rocks and expands, breaking the rock apart

Front 6

litter

Back 6

leaves, twigs, and other organic matter in the A horizon when it is exposed to decomposing organisms

Front 7

climate

Back 7

pattern of weather that occurs in a particular area over many years

Front 8

soil profile

Back 8

vertical section of soil layers

Front 9

mechanical weathering

Back 9

physical process that breaks rocks apart without changing their chemical composition

Front 10

oxidation

Back 10

chemical weathering process that occurs when a material such as iron is exposed to oxygen and water; causes the iron in rock to rust and turn reddish

Front 11

soil

Back 11

material that supports vegetation and is a mixture of weathered rock, mineral fragments, organic matter, water, and air; may take thousands of years to form