1 Soil is a mixture of all of the following EXCEPT __________.A) weathered rock B) organic matter C) erosion D) air 2 __________ erosion occurs when water flows down a slope in a thin layer.A) Outwash B) Till C) Sheet D) Abrasion 3 __________ is a mixture ranging from small particles to large boulders.A) Sediment B) Till C) Deposition D) Outwash 4 Mechanical weathering can result from the action of all of the following EXCEPT __________.A) burrowing by animals B) ice wedging C) carbonic acid D) plant roots 5 U-shaped valleys are formed by __________.A) rivers B) rock slides C) glaciers D) lakes 6 __________ is the result of sand and gravel deposits left by rivers.A) Sediment B) Deposition C) Outwash D) Till 7 __________ are formed when sediment accumulates in large amounts at the mouth of a river.A) Deltas B) Rills C) Tills D) Outwashes 8 Gravity, ice, wind, and water are agents of __________.A) runoff B) erosion C) abrasion D) deflation 9 Which list correctly places channels in order from smallest to largest?A) gully, rill, stream B) rill, gully, stream C) stream, gully, rill D) rill, stream, gully 10 Silt that is carried by the wind and then deposited is called __________.A) loess B) till C) talcum D) flour 11 A __________ occurs along curved surfaces.A) creep B) mudflow C) rock slide D) slump 12 Deflation is an erosional process of __________.A) water B) ice C) landslides D) wind 13 Sediment accumulates to create all of the following EXCEPT __________.A) sand dunes B) mountain bowls C) bars D) deltas 14 Canyons are formed by the erosional processes of __________.A) ice B) streams C) gravity D) wind 15 Chemical weathering is more rapid in areas with __________.A) moist, cool air B) dry, cool air C) warm, moist air D) dry, warm air 16 Water moving over Earth's surface results in __________.A) loess B) runoff C) abrasion D) deflation 17 When materials containing iron are exposed to water and oxygen, __________ can occur.A) wedging B) mechanical weathering C) oxidation D) ironization 18 Rock flour is a result of __________ erosion.A) wind B) water C) glacial D) soil 19 All of the following EXCEPT __________ can weather rock.A) animals B) sunlight C) plants D) freezing and thawing 20 A form of erosion that results in pitted or smoothly polished rocks is __________.A) deflation B) abrasion C) runoff D) till