Hank, Earth's Changing Surface

Question 1

Landforms

Answer 1

A part of the Earth’s surface that has a unique shape.

It was created by nature.

Question 2

Most changes in the landscape of our Earth have occurred over
_________________________

Answer 2

Hundreds, thousands or millions of years.

Question 3

Sediment

Answer 3

Small rocks, pebbles or sand.

Question 4

Weathering

Answer 4

Breaks rocks and sediments into smaller pieces.

Question 5

Abrasion

Answer 5

When rocks and sediment grind against each other and break down into smaller pieces.

Question 6

Erosion

Answer 6

Gradual movement of sediment from one place to another.

Maybe moved by water, glacier or wind.

Question 7

Deposition

Answer 7

Gradual build-up of eroded sediment.

Like a sandbar or a beach.

Question 8

How can water, wind and ice cause erosion and deposition.

Answer 8

After sediment is eroded by moving water, wind or ice

Wind blows over beaches and sand dunes. Glaciers creep slowly down mountainsides.

Question 9

Source of a river

Answer 9

Where a river begins.

Like a spring or melting mountain snow.

Question 10

Riverbanks

Answer 10

The sides of a river.

Question 11

Mouth of a river.

Answer 11

Where a river meets another body of water.

Like a lake, another river or the ocean.

Question 12

Delta

Answer 12

A landform at the mouth of a river.

Made by moving water has deposited silt, sand, soil and rocks.

Question 13

4 factors that shape a river.

Answer 13

1. Slope of the land.
2. Speed of the water.
3. Hardness of the Earth’s surface.
4. Amount of water.

Question 14

Slope

Answer 14

How steep the land is that water is flowing down.

Question 15

Glacier

Answer 15

A huge mass of moving ice.

Question 16

Conditions that form a glacier.

Answer 16

1. Lots of snow.
2. Cold climate all year.
3. Built over hundreds of thousands of years.
4. When big enough, gravity makes it flow downhill.

Question 17

How much do glaciers move?

Answer 17

1-2 inches per day

Question 18

What causes a glacier to move?

Answer 18

Gravity and weight

The bottom of the ice melts and gets slippery.

Question 19

How do glaciers weather rock and mountains?

Answer 19

Glaciers pick up rock as they move down mountains, they cause abrasion, polish the rock, and cut long scratches.

Question 20

Glacial striations

Answer 20

Cuts and long scratches glaciers make in rocks.

Question 21

Moraines

Answer 21

Glaciers can push big piles of rock and sediment into mounds and hills along their sides and in front of them.

Lakes often form behind moraines when glaciers melt.

Question 22

Erratics

Answer 22

Large rocks or boulders carried along by glaciers and then left behind in strange places.

Question 23

How are glacial valleys different from river valleys?

Answer 23

River valleys have a narrow V shape.

Glacial valleys have a wide U shape.

Question 24

Why are people only partially right when they think landforms are shaped by the wind?

Answer 24

Landforms like Hoodoos were shaped by wind AND water.

Question 25

How does cap rock protect a Hoodoo?

Answer 25

Cap rock is a shell of harder rock that protects the soft rock underneath.

Question 26

Explain how sand is formed.

Answer 26

Mountain rock and dirt weathers, washes downhill into rivers, and breaks into smaller and smaller pieces. Wind blows the sand into other rocks and sand until it is shaped like a ball.

Question 27

What 3 conditions are needed for sand dunes to form?

Answer 27

1. Dry and loose sand.
2. A strong, steady wind.
3. An area large enough for sand to blow around.

Question 28

3 types of physical weathering.

Answer 28

1. Abrasion - rocks grinding together.
2. Ice wedging - water freezes in the rocks and breaks them
3. Exfoliation - large slabs of rock can break off and slide away

Question 29

3 types of biological weather

Answer 29

1. Plants - may grow in cracks in rocks and break them up.
2. Animals - beetles, ants, marmots burrowing through cracks.
3. Humans - roads, tunnels, dams and rivers

Question 30

2 types of chemical change

Answer 30

1. Dissolution - acid rain dissolving rock.

2. Oxidation - the iron in minerals reacts with oxygen in the air and rusts

Question 31

The weathering of rock creates ____________ and _____________.

Answer 31

Sediment and Soil

Question 32

Describe the 4 layers that make up the Earth

Answer 32

1. Inner core - a SOLID of iron and nickel
2. Outer core - a LIQUID layer of iron and nickel
3. Mantle - the thickest layer of the earth, solid and semi-molten
4. Crust - solid rock that is the surface of the earth, thin like a shell

Question 33

The earth’s crust is made up of numerous pieces called

_____________________ ___________________ which float on the mantle.

Answer 33

Tectonic plates

Question 34

3 types of plate boundaries

Answer 34

1. Convergent boundaries - 2 plates collide
2. Divergent boundaries - 2 plates move away from one another
3. Transform boundaries - 2 plates slide past each other

Question 35

How are folded mountains formed?

Answer 35

When two plates collide.

One goes down and another goes up making the folded mountain.

Question 36

Explain why millions of years from now, the mountains around us may no longer exist.

Answer 36

Moving water from rainfall and snowmelt start breaking down the mountain. Ice and wind wear it down too.

Question 37

Landscape

Answer 37

A large area of land or scenery.

Usually has many surface features like hills, valleys or rivers.