plate tectonics

Question 1

how thick is the crust and what is it made up of?

Answer 1

up to 70km think and is made up of giant sections called plate tectonics

Question 2

how thick is the mantle and what consistency does it have

Answer 2

up to 2900km think and due to high temperature it has a jam consistency

Question 3

how thick is the outer core and what is it

Answer 3

up to 2200km thick and it is the solid layer

Question 4

how thick is the inner core and what is it

Answer 4

up to 1200km thick and it is a solid layer

Question 5

what are the 4 sections of the earth called

Answer 5

the crust, the mantle, the inner core and the outer core

Question 6

what happens in the mantle and what is the effect of it

Answer 6

convection currents which move the plates around the earths surface

Question 7

why does the earth release huge amounts of heat energy

Answer 7

because of the extremely high temperatures

Question 8

what happens in the upper and lower mantle

Answer 8

in the lower mantle the warmer fluid starts to rise and in the upper mantle the cooler liquid starts to sink

Question 9

what are earthquakes and where do they occur

Answer 9

they are vibrations of the earths crust caused by movement at plate boundaries and major fault line. they mostly happen at plate boundaries and major fault lines

Question 10

what is the focus and where is the epicentre

Answer 10

the focus is where during an earthquake seismic waves move out from the point where rocks of tectonic plates move. the epicentre is directly above the focus on the earths surface

Question 11

what is the richter scale

Answer 11

it is used to measure the magnitude ( power ) of a tremor using an instrument called a seismograph

Question 12

why do earthquakes happen so suddenly

Answer 12

because it is the two plates sliding together which makes the rock suddenly give way with no warning

Question 13

what short term/immediate effects do earthquakes have

Answer 13

electricity cuts off
debris causes injury/death
roads are destroyed
water or gas mains burst
buildings collapse

Question 14

what long term/knock on effects do earthquakes have

Answer 14

people loose livelihood 
landslides
mental trauma
tsunamis
disease

Question 15

how can you limit the damage on a building

Answer 15

identification number for helicopters
rolling weights on roof to counter react shock waves 
automatic shutters on windows
deep and firm building foundations
rubber shock absorbs beneath buildings
open are for pedestrians to assemble

Question 16

what is a volcano

Answer 16

an opening or vent that allowed molten lava to erupt through it and solidify as igneous rock

Question 17

what is the definition of an active, dormant and extinct volcano

Answer 17

an active one is able to erupt at anytime, a dormant one has not erupted for years and an extinct one has not erupted for a very long time and is unlikely to ever again

Question 18

what is lava flow

Answer 18

lava flow is created by a non-explosive eruption. it consist of molten rock, is thick and can travel far without solidifying

Question 19

what is ash

Answer 19

the smoke cloud seen from an eruption which can travel for miles and settles as ash fall

Question 20

what is gas

Answer 20

volcanoes produce gas when erupting. including CO2, steam and sulphur dioxide which smells of rotten eggs

Question 21

what is pyroclastic flow

Answer 21

floods of gas, lava and rock that rush down the volcano after an eruption

Question 22

what is acid rain

Answer 22

the sulphur emissions from volcanoes that cause acid rain

Question 23

what is lahar

Answer 23

a mudflow that comes from a volcano. it can be dangerous due to its energy and speed. it is fluid when moving until stopped which it then solidifies

Question 24

what is the use of a spectrometer

Answer 24

it is used to measure the amount of sulphur dioxide gas that is being emitted by a volcano

Question 25

what is the use of a seismometer

Answer 25

the movement of magma can cause earthquakes and is measured using a seismometer

Question 26

what is the use of tiltmeters and geodmeters

Answer 26

they measure any changes in the slope of a volcano

Question 27

what are the hawaii islands known as and what is the ring of fire

Answer 27

hawaii islands are known as the hotspot and the ring of tide is s wellknown area for eruptions which is isolated by the pacific rim

Question 28

what constructive effects from volcanoes are there

Answer 28

areas of high rainfall ash adds fertiliser
some lava makes good cement and lightweight building materials
hot springs heat towns
underground steam to generate electricity
tourist attractions earning money
water pipes into the lava flow to make a harbour

Question 29

what are some destructive effects of volcanoes

Answer 29

enormous science involved in management protection
loss of life is high
lava flows cause damage to property and ash to farmland
poisonous gases and fumes
lava flows are fast and catch unaware people