PHYSICAL River Landscapes And Processes Flashcards
(25 cards)
What is a DRAINAGE BASIN?
An area of land where all water, precipitation ad streams flow and drain off into a single river, a bay or out to sea
What is DREDGING?
Sediment and other materials are dug up and removed from the bottom of rivers and lakes
What are EMBANKMENTS?
The banks of river are raised up by brick and concrete, to increase the channel capacity and prevent flooding
What is an ESTUARY?
The area where a river meets an ocean, often muddy or silty.
What is a FLOODPLAIN?
The wide, low-lying floor of a river valley. Floodplains are found in the lower course of a river and tend to act as overspill when the river channel is full
What is a LEVEE?
A natural or artificial build up of earth on the banks of a river to prevent water from overspilling and controlling the river flow
What is THALWEG?
The path of fastest water flow in the river
What is ABRASION?
erosion
a type of erosion caused by rivers picking up sediment and rubbing it against the river bed and bank
What is CHANNELISATION?
the deepening and/ or straightening of a river to allow it to carry more water
What is RIVER DISCHARGE?
the volume of water flowing in a river at a certain point, measured in cubic meters per second
What is HYDRAULIC ACTION?
the sheer force of the water hitting the river bed and banks and wearing them away
What are INTERLOCKING SPURS?
an area of higher land jutting out of steep valley sides in a rivers upper coursse
What is MASS MOVEMENT?
the movement of material down a slope due to gravity
What are MEANDERS?
a bend formed in rivers as it winds across the landscape
What is MECHANICAL WEATHERING?
when water freezes it expands by 10% causing the break down of the rock
What is ATTRITION?
rock and pebbles carried by the water are reduced in size as they collide against each other and the river bank
What is SOLUTION?
erosion
chemical action on rocks by river water
What is SOIL CREEP?
mass movement
where individual particles of soil move slowly down the slope
What is SLIDING?
mass movement
where material moves rapidly downslope in one go
What is DEPOSITION?
when there is not enough energy to carry eroded material any furthur. As a rivers discharge and velocity reduces, the heaviest material is deposited first
What is TRACTION?
transport
large boulders/ stones roll along the bed
What is SALTATION?
transport
smaller stones are bounced along the river bed
What is SUSPENSION?
transport
silt and clay-sized particles are carried along within the water flow
What is SOLUTION?
transport
some minerals dissolve in the water and are carried along in the water flow
