Ch10 River Processes

Question 1

Source

Answer 1

Where a river begins.It is normally located on high ground

Question 2

Tributary

Answer 2

A smaller river that joins a larger one

Question 3

Confluence

Answer 3

The point where to or more rivers join together

Question 4

Mouth

Answer 4

The point where the river enters the sea

Question 5

Course

Answer 5

The path a river flows along. The path I’d from the Source of the river to where it enters the sea at its mouth

Question 6

Watershed

Answer 6

A Highland area that separates one drainage basin from another

Question 7

Estuary

Answer 7

Part of a river mouth that is tidal. It is where the river water meets the sea

Question 8

DP. (Dendritic)

Answer 8

°Most common type found in irish river basin, °patterns resemble a tree °normally occurs on gently sloping land,The tributaries flow from narrow valleys into the main river

Question 9

DP Trellis

Answer 9

Drainage patterns occurs where tributaries meet the main river at right angles °they look like a rectangular grid

Question 10

DP radial

Answer 10

°Dp form when tributaries flow from a circular or oval-shaped mountain °the tributaries flow outwards in all directions it resembles spokes from a wheel

Question 11

DP parallel

Answer 11

Dp form when rivers flow alongside each other rather than joining together -due to shape of landscape, their coarse is straight with few or no tributaries joining them

Question 12

Dp Deranged

Answer 12

Dp occurs where tributaries flow in a disorganised or aimless manner typically occurs in swamps or marshlands where the river has a low velocity.

Question 13

What are the 4 main processes if river erosion

Answer 13

1 Hydraulic Action 2 Abrasion 3 Attrition 4 Solution

Question 14

What is hydraulic action

Answer 14

°The sheer force of moving water °as water flows it crashes off riverbank and riverbed the force of collision enlarges joints in rock and breaks off fragments of rock °HA both widens and deepens the river channel

Question 15

What is abrasion

Answer 15

Occurs as a rivers load(eroded material hits off the bed and banks of a river °Its most effective in times of flood when river is capable of carrying a larger load

Question 16

What is attrition

Answer 16

Occurs as rocks and pebbles being carried by the river hit off each other

Question 17

What is solution

Answer 17

Occurs when soluble rocks in the river channel are dissolved by weak acids in the water

Question 18

What are the processes of river transportation

Answer 18

1 solution 2 suspension 3 saltation 4 traction

Question 19

What is solution in transportation

Answer 19

Occurs when soluble rocks are dissolved and carried away in solution °accounts for a small percentage of rivers load transported and need little energy to transport

Question 20

What is suspension

Answer 20

Occurs as clay and silt particles are lifted off the riverbed and carried as a suspended load,much of the rivers load is transported by suspension

Question 21

What is saltation

Answer 21

Occurs when small pebbles and stones that are too heavy to be carried in suspension for a long time are bounced along the bed of the river

Question 22

What is traction

Answer 22

Occurs when heavy materials such as large rocks are dragged along the riverbed °transportation requires great amount of energy and usually occurs when the river has a great level of volume and velocity

Question 23

River deposition occurs when a river loses its velocity(speed the water travels)

Answer 23

•when a river slows down it loses energy.

•human interference can reduce speed of a river through construction of dams as it blocks the rivers coarse

Question 24

River deposition when a river loses its volume(the amount of water in river channel)

Answer 24

•when a river loses some of its volume its energy is reduced

•during hot weather,evaporation reduces the rivers volume,causing deposition to occur

Question 25

River deposition increased load

Answer 25

During heavy rainfall tributaries joining the main river can carry alot of sediment. The main river is unable to transport all of its load causing its channel to become clogged with sediment