The long profile of a river

Question 1

what are the three courses of a long profile?

Answer 1

-upper course
-mid course
-lower course

Question 2

what are the 3 changes that occur between the courses?

Answer 2

-the relief of the land
-the width/depth of the valley
-different landforms appear in each course

Question 3

describe how erosion occurs in the upper course of a river

Answer 3

mostly vertical erosion by hydraulic action

Question 4

describe how erosion occurs in the mid-course of a river

Answer 4

less vertical erosion, more lateral erosion. Much attrition and abrasion, some solution

Question 5

describe how erosion occurs in the lower course of a river

Answer 5

very little erosion, only lateral erosion

Question 6

describe how transportation occurs in the upper course of a river

Answer 6

mostly traction, large boulders moved

Question 7

describe how transportation occurs in the mid-course of a river

Answer 7

mostly suspension, increased traction, load becomes smaller and less angular

Question 8

describe how transportation occurs in the lower course of a river

Answer 8

mostly suspension and solution, very small particles of load, great quantity of load

Question 9

describe how deposition occurs in the upper course of a river

Answer 9

large boulders deposited

Question 10

describe how deposition occurs in the mid-course of a river

Answer 10

more deposition, especially on the inside bend of meanders

Question 11

describe how deposition occurs in the lower course of a river

Answer 11

deposition now the main fluvial process, fine material is now deposited

Question 12

what is discharge?

Answer 12

the volume of water passing through a given point in a river

Question 13

how does the discharge change as you go along the course of a river?

Answer 13

discharge increases as you go downstream as tributary streams join the main river and add their volume of water to it

Question 14

what does the velocity of a river depend on?

Answer 14

how much water comes into contact with the channels, banks and bed

Question 15

how does the velocity change as you go along the course of a river?

Answer 15

the average velocity increases along its course

Question 16

describe the channel cross profile of the upper course of a river

Answer 16

channel is very narrow and very shallow

Question 17

describe the channel cross profile of the mid-course of a river

Answer 17

channel becomes wider and for many rivers it will be over a metre deep

Question 18

describe the channel cross profile of the lower course of a river

Answer 18

channel becomes wider still and the channel is much deeper

Question 19

explain the channel cross profile of the upper course of a river

Answer 19

the river erodes its bed by hydraulic and abrasive action

Question 20

explain the channel cross profile of the mid-course of a river

Answer 20

as the river goes downstream it is joined by tributaries which increases the volume of water which in turn erode more

Question 21

explain the channel cross profile of the lower course of a river

Answer 21

the channel becomes wider downstream as the gradient become less steep, there is less vertical erosion

Question 22

describe the valley cross profile of the upper course of a river

Answer 22

steep-sided, narrow and deep, v-shaped valley

Question 23

describe the valley cross profile of the mid-course of a river

Answer 23

valley broadens out, it now has a small flood plain, valley sides are not as steep

Question 24

describe the valley cross profile of the lower course of a river

Answer 24

large expanse of flat flood plain on either side of the river

Question 25

explain the valley cross profile of the upper course of a river

Answer 25

vertical erosion is the dominant process, this creates a slope that weathered material from the valley sides can fall down

Question 26

explain the channel cross profile of the mid-course of a river

Answer 26

the gradient is less steep so the river starts to meander and erode laterally into the valley sides

Question 27

explain the channel cross profile of the lower course of a river

Answer 27

deposition from floods builds up the flood plain, this builds up and widens the valley