Rivers

Question	Answer
Drainage basin	Area of land that is drained by a river and its tributaries.
Watershed	Ridge of high land that separates one drainage basin from another.
River discharge	The volume of water that is carried by a river at a given point.
Velocity	The speed that the water in the river is moving at.
Gradient	How steep the slope that a river is flowing on. The steeper the slope, that faster the river should flow.
Turbulent flow	The type of flow that occurs where the riverbed is rough. As the water flows, it is mixed and thrown around. It is important for erosion and transportation.
Drainage pattern	The overall layout of a river and its tributaries on an area.
Dendritic drainage pattern	Drainage pattern that resembles a tree in Winter.Develops on gently sloping land. Eg River Shannon.
Radial drainage pattern	Streams drain outwards in all directions, away from a high central point. Eg the Twelve Pins in Co. Mayo.
Trellised drainage pattern	Drainage pattern where tributaries join the main river at right angles, in a ridge and valley landscape or in glaciated valleys. Eg. River Lee
Deranged drainage pattern	Drainage pattern that has a chaotic appearance. Rivers run in random patterns creating small lakes. This is associated with marshy or boggy lowlands, and glaciated landscapes. Eg. Monaghan
Dendritic drainage pattern	Image: Dendritic Pattern (binary/octet-stream)
Radial drainage pattern	Image: Radial (binary/octet-stream)
Trellis drainage pattern	Image: Trellis (binary/octet-stream)
Deranged drainage pattern	Image: Deranged (binary/octet-stream)
Erosion	A collection of processes that wear away the landscape and transport a load to another location.
Hydraulic action	Erosion caused by the force of moving water.
Cavitation	A form of hydraulic action that takes place when air bubbles in the water collapse sending out tiny shockwaves.
Abrasion	When the river uses the force of its load to erode.
Attrition	A way of eroding the rivers load through small collisions between the particles of the load.
Solution	Chemical weathering of the rock, whereby soft rocks are dissolved by the water in the river.
Vertical erosion	Erosion that is active in the youthful stage of a river, making the valley deeper.
Lateral erosion	Erosion that is active in the mature and old age stage of the river, making the river channel and valley wider.
Headward erosion	Erosion that is active upstream of the rivers source, lengthening the river in an upstream direction.
Load	The various materials which are transported by the river
Solution	Slightly acidic water in the river dissolves soluble minerals in the rock, transporting them as solution.
Suspension	The lightest particles of the load are carried along in the flow of the river without settling.
Saltation	Particles of sand, gravle and small stones are picked up by the water, carried forward only to be dropped to the riverbed. Particles hop downstream.
Traction	The largest stones and boulders are rolled and dragged along the riverbed.
Bedload	The load the river moves along its bed by saltation or traction.
Alluvium	The general term for sorted sediments (sand, clay and silt) that are deposited in layers (strata) by rivers.
Long profile	Shows how a rivers gradient changes as it flows from its source to its mouth.
Base level	The level below which a river cannot erode vertically. This may be sea level or where a river flows into a lake or reservoir.
Youthful/Upper course	In this stage, the gradient is steep, the river channel is narrow and erosion is the dominant process.
Youthful/Upper course	Image: Upper Course (binary/octet-stream)
Mature/Middle course	The river has more energy and volume in this stage. The gradient is gentler and the river course has become deeper. Vertical erosion gives way to lateral erosion.
Mature/Middle course	Image: Middle Course (binary/octet-stream)
Old/Lower Course	Volume of water is at its greatest in this stage. River channel is deep and wide. While there is some lateral erosion, deposition is the dominant process.
Old/Lower Course	Image: Lower Course (binary/octet-stream)
Long profile	Image: Long Profile (binary/octet-stream)
V-shaped valley	Image: V Shaped Valley Photo (binary/octet-stream)
V-shaped valley	Image: V Shaped Valley Diagram (binary/octet-stream)
Waterfall	Image: Waterfall Diagram (binary/octet-stream)
Waterfall	Image: Tirc Falls Killarney (binary/octet-stream)
Meanders	Image: Meander Photo (binary/octet-stream)
Meanders	Image: Meander Diagram (binary/octet-stream)
Ox-bow lake	Image: Oxbow Lake Photo (binary/octet-stream)
Oxbow lake	Image: Oxbow Lake Diagram (binary/octet-stream)
Source	The place where a river starts.
Tributary	Small river that joins the main river.
Confluence	The point where a tributary joins the main river.
Mouth	Where the river goes into the sea.
Flood plain	Image: Flood Plain (binary/octet-stream)
Flood plain	Image: Flood Plain Diagram (binary/octet-stream)
Flood plain	The area around a river that's prone to flooding.
Levee	Image: Levee (binary/octet-stream)

Next up

Description

Resource summary

Similar

	Created by Laura O' Sullivan about 5 years ago