Plate Tectonics

Question 1

What is the mantle

Answer 1

The mantle is a semi liquid layer of magma that moves due to convection currents

Question 2

What is the crust

Answer 2

The crust is a solid layer of rock on the surface of the planet. The thickness varies between 3 and 30

Question 3

What is the outer core

Answer 3

The liquid part of the core which has a similar composition to the inner core

Question 4

What is the inner core.

Answer 4

The inner core the solid part at the centre of the earth it’s made of iron and nickel and has temperatures reaching 5500c

Question 5

How do convection currents cause the tectonic plates to move

Answer 5

The crost is broken up into seven large sections and various smaller sections which are floating on the mantle and moving towards, away from and past each other. The heat from the inner core tries to escape and (boils) semi-molten rocks in the mantle and slowly moves the crust above it

Question 6

What plate boundary is the indo Australian plate

Answer 6

Collision

Question 7

What type of plate boundary is the South American plate

Answer 7

Deconstructive

Question 8

What type of plate boundary is the North American plate

Answer 8

Constructive

Question 9

What type of plate boundary is the Eurasian plate

Answer 9

Conservative

Question 10

What is a volcano

Answer 10

A volcano is an opening or rupture in the earths surface of crust which allows hot magma, volcanic ash and gases to escape from the surface

Question 11

What is a main vent

Answer 11

The opening for the magma to go up through the volcano

Question 12

What is the magma chamber

Answer 12

The source of the molten rock

Question 13

What is the crater

Answer 13

The circular basin shape on the top of the volcano

Question 14

What is the secondary cone

Answer 14

A secondary vent formed on the side of the mountain

Question 15

What are volcanic bombs

Answer 15

Airborne material from a volcanic eruption

Question 16

What does active mean

Answer 16

A volcano that could erupt at any given point

Question 17

What does dormant mean

Answer 17

A volcano that is sleeping and hasn’t erupted for years

Question 18

What does extinct mean

Answer 18

A volcano that will never be active again

Question 19

Volcanic hazards
Ash

Answer 19

The smoke cloud normally seen from an eruption is ash.
It can travel several miles and settles as ash-fall
it can produce very fertile soil

Question 20

Volcanic hazards
Gas

Answer 20

Volcano produce gas when they are erupting.
This includes co2 steam and sulphur dioxide volcano gases smell of rotten eggs due to the sulphur present.

Question 21

Volcanic hazards
Acid rain

Answer 21

The sulphur emissions from volcanoes can cause acid rain
Acid rain can be dangerous to plant and animals it can also harm humans

Question 22

Volcanic hazards
Lahar

Answer 22

Lahar is a mudflow that comes from a volcano.
It can be dangerous due to its energy @nd speed. It’s fluid when moving solidifies when stopped

Question 23

Volcanic hazards
Pyroclastic flow

Answer 23

Pyrclastic flows are floods of gas lava and rock that rush down the volcano after an eruption. Their hot gases and high speed make them lethal to anything in their path

Question 24

Volcanic hazards
Lava flow

Answer 24

Lava flow is created by a non-explosive eruption.
It consists of molten rock
It’s thick and can travel very far before solidifying
It can be very destructive but it’s slow moving

Question 25

What are benefits of volcanoes

Answer 25

Lava produces fertile soil once its been weathered Geo-thermal energy means that the cost of living can be massively reduced Volcanoes can help to generate income to the region through tourist numbers Volcanoes create new land over time and provide habitat for several unique wildlife species

Question 26

How can you predict volcanoes

Answer 26

Volcanic emissions may increase before an eruption Spectrometers can be used to measure the amount of sulphur dioxide gas that is being produced but the volcano Before an eruption magma collects in the magma chamber the movement of magma can cause earthquakes these can be measured by using seismometer The shape of a volcano may change in the build up to an eruption due to magma gathering in the magma chamber or vents. Tilt-meters and geometers can measure any changes in the slope of a volcano Water levels may also change if magma Oozes onto the floor of a river or lake on the volcano which is measured by a thermometer

Question 27

What are earthquakes

Answer 27

Earthquakes are vibrations of the earths crust caused by movement at plate boundaries and major fault lines. Earthquakes can occur at all major plate boundaries but the most severe earthquakes usually occur at conservative and destructive plate boundaries

Question 28

What causes an earthquake

Answer 28

An earth quake is when the ground shakes. It produces long shocks that travel out from the centre of the crust just like a stone being thrown into a pond. The waves spread out from the focus. The focus is the point where the earthquake starts. Near the focus the waves are stronger causing more damage. The epicentre is the point on the earths surface immediately above the focus

Question 29

How is a earthquake measured

Answer 29

The Richter scale can be used to measure the magnitude of a tremor using an instrument called a seismograph. It’s a logarithmic scale which means that a size 6 earthquake on the scale is ten times larger than a size 5 and 100 times larger than a size 4

Question 30

Impacts of earthquakes Short term

Answer 30

Roads destroyed Buildings collapse Debris cause injury/death Water or gas mains burst Electricity cuts off

Question 31

Impacts of earthquakes long term

Answer 31

Disease Mental trauma People lose livelihood Tsunamis Landslides

Question 32

How can you limit earthquake damage

Answer 32

Emergency services can practice for disaster Stock up on medicine food blankets Educate the population in what to do during and after Construct buildings and roads that withstand shaking

Question 33

What are tsunamis

Answer 33

Tsunamis are tidal waves caused by underwater earthquakes. Tsunami means harbour wave in Japanese. Tsunamis travel at speeds between 400 and 600mph

Question 34

The Indian Ocean earthquake

Answer 34

On 26th December 2004 a magnitude 9 earthquake occurred beneath the Indian Ocean at the sundra trench. The earthquake caused by a slip along a fault in the earths crust where the indo-Australian plate is subdued by the Burma plate. The tsunami spread across the Indian Ocean affecting coastal areas of 14 countries