Chapter 8 Erosion & Deposition

Changing Earth’s Surface Vocabulary Weathering – Erosion – Sediment – Deposition – Mass Movement – process that breaks down rocks movement of rock and soil from one place to another material moved by erosion when sediment is laid down movement of sediment downhill due to gravity

Mass Movement Gravity Caused by – Types Landslide Mudflow Slump Creep Most destructive – rock and soil slide quickly downslope Rapid – water, rock, & soil Rock & soil move in one whole chunk Slowest – barely noticeable – bent trees

Water Erosion Water that travels over Earth’s surface Runoff – Factors affecting runoff Amount of rain an area receives Vegetation: more = less Type of soil Shape of the land: steep = more How people use the land Water that travels over Earth’s surface

Erosion by Rivers Create Valleys Waterfalls Floodplains Meanders Oxbow lakes

River Deposits Alluvial Fan Deltas Soil on Flood Plains

Groundwater Water that is underground Erosion through chemical weathering Form Caves Stalactites Stalagmites Sinkholes

Force of Moving Water Vocabulary Energy – Potential energy – Kinetic energy – Load – Abrasion – Ability to do work or cause change Stored energy Energy due to an object’s motion The amount of sediment a river carries Wearing away of rock by grinding action

Water S peed and Sediment Load Factors Slope: Volume of Flow: Streambed Shape: Steeper = faster = more sediment More = faster = more sediment Deeper = less friction = faster = more sediment

Glaciers Glacier – Types Valley Continental Large mass of moving ice

Glacial Erosion Two processes Features Plucking Abrasion Features U-shaped valley Cirque Horn Fiord Arete A process in which rocks are picked up Shape of valley due to glacial erosion Bowl-shaped hollow Sharpened peak Deep valley filled with sea water Sharp ridge separating two cirques

Glacial Deposition Types of features Till Moraine Prairie Potholes Drumlin Kettle Lake

Waves wind Energy comes from - How they cause erosion – Impact by waves Abrasion wind

Features caused by Waves Erosional – Cliff Sea stack Cave Depositional Beach Spit Barrier Beach

Erosion by Wind How Erosional features Depositional Features Deflation - Abrasion - Erosional features Desert Pavement Polished rocks Depositional Features Sand dunes Loess Process by which wind removes surface materials The grinding away of rock by impact of other rocks