Rivers and Coasts

• lower course of river: river flows faster and deeper, more energy is released, more erosion
• middle course of river: a river that has a wide valley and a wide floodplain
• upper course of river: the part of a river that flows through a valley and is exposed to the force of gravity
• types of erosion: abrasion attrition chemical weathering frost wedging
• attrition: the process of reducing something's strength or effectiveness through sustained attack or pressure
• abrasion: when rocks are rubbed against each other, causing them to break down
• solution: disolving rock in water, dissolved minerals are carried away in solution
• hydralic action: water flowing over an object with great force breaking it apart
• types of transportation: solution suspension traction and saltation
• traction: larger boulders are rolled along the river bed by the force of the water
• suspension: fine sediement is suspended in water, not settling
• saltation: large stones hopping across the river bed
• solution: minerals are dissolved in water carried by the river
• river long profile: a profile of a river that shows the change in the river's course over time
• river cross profile: a profile of a river showing the course of the river and the direction of the river flow
• oxbow lake: A lake formed by a meander of a river that has been cut off from its main channel
• meander: (of a river or road) follow a winding course
• weathering: the breaking down or dissolving of rocks on the earths surface
• mechanical weathering: rocks are broken down by physical forces of water, ice or wind
• chemical weathering: the breakdown of rocks by chemical reactions in the atmosphere
• rockfalls: when fragments of rocks fall down a cliff, they can cause damage to buildings and infrastructure
• landslides: large masses of rock move rapidly downhill due to gravity
• constructive waves: waves with a strong wash and weak backwash which deposit material to construct the beach
• destructive wave: weak wash with strong backwash which erodes material
• spit formation: longshore drift causes sand to build up on one side of the bay forming a spit
• longshore drift: movement of sediment along the coastline caused by waves hitting at an angle