The Earth's Surface

Question 1

The Crust

Answer 1

The crust is the outer layer of the earth and is made out of rock that is 60km think

Question 2

The mantle

Answer 2

The mantle is the middle layer of the earth and is made out of molten and semi-molten rock called magma. It is up to 4000°c

Question 3

The Core

Answer 3

There are two parts to the core:

Inner core and outer core

Question 4

Outer core

Answer 4

The outer core is made up of molten iron and nickel

Question 5

Inner core

Answer 5

The inner core is solid due to pressure and is more than 5000°c

Question 6

Seven Main Plates

Answer 6

African Plate
Eurasian Plate
Indian Plate
Nazca Plate
Pacific Plate
American Plate
Australian Plate

Question 7

Explain convection currents

Answer 7

Convention currents is when magma is moved around in circular movements in the mantle, which causes plates to move. When the magma rises it becomes cool which makes it harden and sink back down and repeats itself

Question 8

Study of plates

Answer 8

Plate tectonics

Question 9

Before the plates moved

Answer 9

Pangaea was when all the continents were joined as one 225 million years ago

Question 10

Destructive boundaries

Answer 10

This is when two plates are pushed together by convection currents which create fold mountains

Example: The Andes South America

Question 11

Constructive boundaries

Answer 11

This is when two plates are separated by the magma, this allows volcanic activity that results in volcanoes, volcanic islands and mid-ocean ridges

Examples: Iceland and Mid-Atlantic Ridge

Question 12

Passive boundaries

Answer 12

This is when two plates are pushing beside each other, this can cause earthquakes and fault lines

Example: San Andreas fault

Question 13

Volcano

Answer 13

A volcano is a opening in the earths surface that allows magma, ash and gases to come out of from below

Question 14

How does a volcano form

Answer 14

A volcano is formed when magma moves out of the surface through a vent, this is a small opening in the surface. The magma is Stored underground in a magma chamber. The magma then rises through the vent and out of the crater, when magma reaches the surface it becomes lava, the lava then hardens around the vent creating layers most of the time in a cone-shape.

Question 15

Mid-Atlantic Ridge

Answer 15

The Mid-Atlantic ridge is a Chain of mountains found in the Atlantic Ocean, caused by the South American and African Plate pulling apart magma rises up through the fissures and creates mountains.

Question 16

Active Volcano

Answer 16

These volcanos have erupted regularly

Example: Mt St. Helens USA

Question 17

Dormant Volcano

Answer 17

These are volcanos that have not erupted in a long time but could possibly erupt again

Example: Mt. Vesuvius, Italy

Question 18

Extinct volcano

Answer 18

An extinct volcano is a volcano that hasn’t erupted in recorded history

Example: Croghan Hill, Offaly

Question 19

Positive Effects on volcanos

Answer 19

• Tourism
• Hot Springs (Geysers), this hot water is used to generate geothermal energy into peoples homes
• The soil have rich minerals in them which means they are fertile and suitable for farmers
• volcanos create land for farming/housing

Question 20

Negative effects from volcanoes

Answer 20

• Gases such as sulphur dioxide is thrown into the aire which can poison people nearby and cause acid rain later on
• lava burns everything
• loss in life
• if a volcano is on a snow capped mountain the lava and snow mix and creates mudflows which are called lahars

Question 21

What’s an earthquake

Answer 21

An earthquake is a sudden tremor or vibration in the earth.
When plates are sliding against each other it builds up a lot of pressure along a fault line, when a sudden release of pressure happens it can result in an earthquake.

Question 22

What’s a focus

Answer 22

Where the earthquake is happening underground

Question 23

What’s an epicentre

Answer 23

Directly above the epicentre where the earthquake happens