Weathering, Erosion & Deposition and Soils Study Guide Weathering, Erosion, & Deposition Vocabulary 1. delta- a large mass of deposited sediment at the mouth of a river. 2. deposition- the dropping of sediment by wind, water, ice or gravity 3. erosion- the movement of weathered rock material from one place to another 4. glacier- a large mass of slow-moving ice that flows down a slope 5. weathering- the slow breaking apart or wearing away of rock into smaller pieces. WeatheringBreaking ErosionMoving DepositionDropping The four causes of weathering are: moving water, wind, ice, growing plant roots. An example of erosion would be: wind moving sand from a dune. Remember that erosion is the moving part of the process. Deposition causes a delta to be created at the end, or mouth, of a river. Know the following Causes and Effects of Erosion. Causes moving river water gravity acid rain glacier ocean-waves Effects form deep canyons pulls soils and rocks downhill cause caves carve out mountain sides change shorelines Be able to explain how weathering, erosion and deposition are related. Weathering is the breaking down of rocks into smaller pieces. Then, erosion is what causes the smaller pieces to be moved. Finally, deposition drops or deposits these pieces into a new place. Soils Vocabulary 1. soil- made up of bits of rock, minerals and material that was part of once-living things; loose material that covers much of the Earth’s surface. 2. humus- the decayed remains of plants and animals 3. topsoil- the uppermost layer of soil; contains large amounts of humus 4. subsoil- the layer of soil just below topsoil; contains little amounts of humus 5. bedrock- unweathered rock that lies below the subsoil The Four Types of Soil 1. sand- often found at the beach; large particles; does not hold water well 2. silt- small particles; holds water well 3. clay- smallest particles; water often puddles 4. loam- a mixture of sand, silt, clay and humus; many plants grow well in loam The Four Ingredients of Soil 1. humus 2. pieces of rocks & minerals 3. air 4. water Facts to Know: -You would most likely find large amounts of humus in forests. Humus is full of rich nutrients that helps plants to grow. -Clay is often used to make pots because the water makes it sticky. -Loam is the best type of soil for growing plants because it has good water capacity and lots of humus. Layers of Soil Topsoil- the layer of soil right below the grass; this layer has the most humus Subsoil- layer that contains little humus and is right below the topsoil layer Bedrock- solid rock that lays right below the subsoil