Earth Sciece

Question 1

Lithosphere

Answer 1

the hard outer part of the earth, consisting of the crust and upper mantle.

Question 2

Asthenosphere

Answer 2

the upper layer of the earth’s mantle, below the lithosphere, in which there is relatively low resistance to plastic flow and convection is thought to occur.

Question 3

Mantle

Answer 3

is the part of the earth between the core and the the crust is the mantle. It is about 2,900 kilometers thick and makes up nearly 80 percent of the Earth’s total volume.The mantle is made up of magma and rock.

Question 4

Core

Answer 4

The outer core of the Earth is a liquid layer about 2,260 kilometers thick. It is made of iron and nickel. This is above the Earth’s solid inner core and below the mantle

Question 5

Seismic

Answer 5

waves of energy that travel through the Earth’s crust, caused by earthquakes

Question 6

Continental drift

Answer 6

movement of the plates of the Earth’s crust in relation to each other

Question 7

Pangaea

Answer 7

a super-continent that existed about 225 million years ago. All of the landmasses that existed at this time were joined together to form this super-continent.

Question 8

Panthalassa

Answer 8

the vast sea surrounding the supercontinent of Pangaea

Question 9

Tremors

Answer 9

vibration on the Earth’s surface caused by an earthquake

Question 10

Epicentre

Answer 10

the point on the Earth’s centre directly above the site where an earthquake originates

Question 11

Focus

Answer 11

the point at which an earthquake begins

Question 12

Triangulation

Answer 12

finding a location by using at least three different sources of detection

Question 13

Seismograph

Answer 13

an instrument used to detect and measure the intensity of an earthquake

Question 14

Richter scale

Answer 14

a scale that measures the amount of energy released during an earthquake

Question 15

P-waves or Primary waves

Answer 15

compression waves that move through the Earth in the same way that sound waves move through air

Question 16

Secondary

Answer 16

the second set of waves to be detected after P-waves. During seismic activity, secondary waves or S-waves travel in the form of transverse waves

Question 17

S-waves

Answer 17

the second set of waves to be detected after P-waves. During seismic activity, secondary waves or S-waves travel in the form of transverse waves.

Question 18

Body waves

Answer 18

waves that travel through the interior of the Earth; P-waves and S-waves are said to be body waves

Question 19

Surface waves

Answer 19

(or L-waves) earthquake waves which travel only through the Earth’s crust; they are responsible for the majority of an earthquake’s destructive power

Question 20

Seismologists

Answer 20

a scientist who studies earthquakes

Question 21

Tsunamis

Answer 21

a powerful ocean wave triggered by an undersea earth movement

Question 22

Meltdowns:

Answer 22

the melting of a nuclear-reactor core as a result of a serious nuclear accident

Question 23

Volcanoes

Answer 23

natural opening in the Earth’s crust connected to areas of molten rock deep inside the crust

Question 24

Magma

Answer 24

a very hot mixture of molten rock and gases, just below the Earth’s surface, that has come from the mantle

Question 25

Lava

Answer 25

mixture of molten rock and gases that has reached the Earth’s surface from a volcano

Question 26

Volcanic bombs

Answer 26

large rock fragment that is blown out of erupting volcanoes; also known as a lava bomb

Question 27

Active

Answer 27

describes a volcano that is erupting or has recently erupted

Question 28

Extinct

Answer 28

describes a volcano that has not erupted for thousands of years and is effectively dead

Question 29

Dormant

Answer 29

describes a volcano that has not erupted for more than 20 years but is not considered extinct