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Flashcards in Chapter 8 Deck (36):
1

Watershed

Is the line dividing a river from another.

2

Tributaries

Are smaller rivers on the normal one.

3

Confluence

Is where the tributaries meet the river.

4

Estuary

Is the mouth of the river.

5

Delta

Is land the forms the river mouths.

6

Mouth

Is where the river meets the river or sea.

7

Source

Is where the river begins

8

Course

Is the path of the river from source to mouth.

9

Basin

Is the area drained by its river and tributaries.

10

Distributaries

Are the smaller rivers that break off from the main river as it enters the sea.

11

Processes of river transportation

Are hydraulic action, abrasion, attrition and solution, solution, saltation, suspension and traction.

12

Hydraulic action

Is the the erosion by the force of moving water

13

Abrasion

Is when the river uses its load to erode the bed and banks.

14

Attrition

Is when the load bang against each other and the rocks are smoothed

15

Solution

Is when some rocks dissolve

16

Solution

Is when rock minerals dissolve and are carried away

17

Saltation

Is when small stones bounce off the bottom of the river

18

Suspension

Is when light material is carried along.

19

Traction

Is when larger materials are rolled along the river bed

20

The old age stage

Is when the river slows down and it deposits its load. Some features are ox-bow lakes, levees and deltas

21

Ox-bow lake

The neck of the meander narrows, eventually breaks off into a straight line and an ox-bow lake is formed by the deposition cutting it off

22

Levee

Is when a river floods and all the water and deposits flow up onto the floodplain and the deposits stay there and eventually build up.

23

Delta

Is when the river slows down and deposits its load which forms a delta. An example is the Mississippi River in USA, the Nile in Egypt.

24

River features

Are the watershed, tributaries, confluence, estuary, delta, mouth, source, course, basin and distributaries

25

Rivers and people

Rivers can flood due to heavy rainfall or how people manage the rivers. People can drown, farmland and houses are flooded, food prices increase because of the decreasing crops.

26

Dams

A dam is a barrier build to hold back water. They can act to generate energy or to store water.

27

Advantages of dams

They produce pollution-free energy. Water is stored. They are used to prevent too much water flowing into the middle and lower course.

28

Disadvantages of dams

Good farmland is flooded when dams are being created. Many people have to move house. There is danger in case it floods or overflows.

29

The youthful stage

This is where the most erosion occurs. It forms V-shaped valleys and waterfalls.

30

V-shaped valleys

Occur when the river erodes the valley and flows down as a result of gravity. It continues and gradually looks V-shaped.

31

Waterfalls

Occur when the river erodes soft rock if front of hard rock. It undercuts the hard rock which eventually breaks off and that makes a waterfall.

32

Mature stage

The slope is flatter than the youthful stage. It doesn't flow down as fast. It forms flood plains and meanders.

33

Flood plain

Is made when a river floods and lays down alluvium on the valley floor.

34

Meander

Are made when a river erodes its outer bend and deposits on its inner bend.

35

Erosion

The wearing away of rock, it's transportation and its deposition

36

Deposition

When a river slows down, loses energy, deposits some material
Happens when a river enters a lake, the inner bends of a meander, flat plain or when a river enters the sea