geology-rivers

Question 1

what are the processes of erosion?

Answer 1

hydraulic action, attrition, abrasion, solution

Question 2

what are the processes of transportation?

Answer 2

traction, suspension, saltation, solution

Question 3

what is hydraulic action?

Answer 3

water and air is forced into cracks of a rock, breaking its structure

Question 4

what is abrasion?

Answer 4

rock fragments carried by the river, hitting the banks causing them to wear down

Question 5

what is attrition?

Answer 5

rock fragments transported by river which causes them to break into smaller rounded sediment

Question 6

what is solution? (erosion)

Answer 6

rocks containing calcium carbonate

Question 7

what is suspension?

Answer 7

small particles are carried within the water by turbulent flow

Question 8

what is traction?

Answer 8

heavy material is rolled along the river bed, requires most energy

Question 9

what is saltation?

Answer 9

sand-sized particles particles bounced along the river bed

Question 10

what is solution? (transportation)

Answer 10

some minerals will dissolve in water and are carried

Question 11

what is a meander?

Answer 11

the river bends in its middle course

Question 12

what is the first step in forming a waterfall?

Answer 12

water flows over hard and soft rock

Question 13

what is the second step in forming a waterfall?

Answer 13

soft rock is eroded by water- forms a small drop

Question 14

what is the third step in forming a waterfall?

Answer 14

continued erosion of soft rock will undercut hard rock

Question 15

what is the fourth step in forming a waterfall?

Answer 15

eroded rock creates hollow base of waterfall known as a plunge pool

Question 16

what is the fifth step in a waterfall?

Answer 16

due to overhang, hard rock collapses, waterfall retreats forming gorge

Question 17

how does flooding affect people?

Answer 17

• damage housing
• businesses
• damage to transportation

Question 18

what are the rock types?

Answer 18

• igneous
• sedimentary
• metamorphic

Question 19

what is igneous rock?

Answer 19

formed from volcanic eruptions, VERY RESISTANT, e.g. granite

Question 20

what is sedimentary rock?

Answer 20

formed from eroded sediments deposited. some are resistant like limestone

Question 21

what is metamorphic rock?

Answer 21

formed due to changing heat & pressure - makes it RESISTANT e.g. marble, slate

Question 22

what is physical weathering?

Answer 22

caused by changes in temperature & pressure

Question 23

what is chemical weathering?

Answer 23

caused by the action of water & chemicals

Question 24

what is biological weathering?

Answer 24

caused by the action of plants & animals (either physical or chemical)

Question 25

what is glaciation?

Answer 25

period when land is covered in ice. rivers go to V--> U shape valleys due to movement of ice

Question 26

where is the source of a river?

Answer 26

point at which the river starts, upper course

Question 27

where is the mouth of a river?

Answer 27

point at which the river ends, slow flow, wide

Question 28

describe the upper course of a river.

Answer 28

steep, shallow river channel, narrow

Question 29

describe the middle course of a river.

Answer 29

deeper, wider, gentler sides

Question 30

describe the lower course of a river.

Answer 30

flat, widest, deepest