River valley

Question 1

what is the rivers course

Answer 1

the path of a river as it flows downhill

Question 2

what are the 3 courses of a river

Answer 2

-upper
-middle
-lower

Question 3

what do rivers form as they flow downhill

Answer 3

channels and valleys

Question 4

what does the long profile of a river tell you

Answer 4

how the gradient changes over different courses

Question 5

what does the cross profile of a river show you

Answer 5

what a cross section of the river would look like

Question 6

describe the upper course of a river

Answer 6

-steep
-v shaped valley
-steep sides
- narrow,shallow channel

Question 7

describe the middle course of a river

Answer 7

-medium gradient
-gently, sloping valley sides
-wider deeper channel

Question 8

describe the lower course of a river

Answer 8

-gentle gradient
-very wide
-very flat valley
-very wide deep channel

Question 9

name the 2 types of erosion

Answer 9

lateral
vertical

Question 10

what changes the cross profile of a river

Answer 10

vertical and lateral erosion

Question 11

what’s vertical erosion

Answer 11

-deepens river valleys and makes the channels **v-shaped **
-dominant in upper course of river
-high turbulence causes rough rocks to be **scraped along river bed **causing intense downward erosion

Question 12

what’s lateral erosion

Answer 12

-widens river valley and channel during formation of meanders
-dominant in middle and lower courses

Question 13

what are 4processes of a river

Answer 13

-hydraulic action
-abrasion
-attrition
-solution

Question 14

what’s hydraulic action

Answer 14

the force the water breaks rock particles away from the river channel

Question 15

what’s hydraulic action

Answer 15

the force the water breaks rock particles away from the river channel

Question 16

what’s abrasion

Answer 16

eroded rocks picked up by the river scrape and rub against the channel causing it to wear away

Question 17

what’s attrition

Answer 17

eroded rocks picked up by the river smash into each other and break into smaller fragments. their edges become rounded as they rub together

Question 18

what’s solution

Answer 18

river water dissolved some type of rock

Question 19

what are the 4 processes of transportation

Answer 19

traction
saltation
suspension
solution

Question 20

transportation is the

Answer 20

movement of eroded material

Question 21

what does the transport of material depend on

Answer 21

the velocity of the water and size of particles

Question 22

what is traction

Answer 22

large particles like boulders are pushed along the river bed by the force of water

Question 23

what’s suspension

Answer 23

small particles like silt and call are carried along the water

Question 24

what’s saltation

Answer 24

pebble sized materials are bounced along the river bed by the force of water

Question 25

what’s solution

Answer 25

soluble materials dissolve in the water and are carried along

Question 26

what’s deposition

Answer 26

when a river drops the eroded material it’s transporting

Question 27

where are waterfalls and gorges found

Answer 27

upper course of the river

Question 28

explain how a waterfall is formed

Answer 28

-river flows over area of hard rock and then soft rock -the soft rock is eroded more then hard rock creating a step in the river -as water goes over step it erodes more and more of softer rock -steep drop

Question 29

where do waterfalls form

Answer 29

they form where a river flows over an area of hard rock followed by soft rock

Question 30

what are soft engineering methods to reduce the effect of flooding

Answer 30

-flood warning -preparation -flood plain -zoning