Earth Science

Question 1

Lithosphere

Answer 1

The outer layer of the Earth consisting of the crust and upper mantle

Question 2

Asthenosphere

Answer 2

The upper layer of the Earth’s mantle, where there is relatively low resistance to plastic flow.

Question 3

Mantle

Answer 3

The mantle is the layer of the Earth between the core and the crust. It makes up for nearly 80% of the Earth’s total volume.

Question 4

Core

Answer 4

The core is the central region of the Earth. It consists of two parts: the (solid) inner core and the (liquid) outer core

Question 5

Seismic Waves

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

Plate tectonics

Answer 9

the theory concerning the movement of the continental plates

Question 10

Convection Current

Answer 10

circular movement that occurs when warmer, less dense fluid particles rise and cooler, denser fluid particles sink

Question 11

Continental Crust

Answer 11

the plates of the Earth’s crust that make up the land

Question 12

Oceanic crust

Answer 12

one of the types of crust that makes up the Earth’s outer layer. Oceanic crust is thinner than continental crust and made up of dense, heavy rocks such as basalt.

Question 13

Subduction

Answer 13

process in which two tectonic plates push against each other, and oceanic crust sinks below the less dense continental crust

Question 14

Destructive plate boundaries

Answer 14

a convergent boundary where two plates collide

Question 15

Constructive plate boundaries

Answer 15

plate that creates new land from cooling magma

Question 16

Ocean ridges

Answer 16

an area where the tectonic plates move apart, allowing magma from the mantle to rise, forming underwater volcanoes and creating new oceanic crust as it is cooled and solidified by sea water

Question 17

Conservative plate boundaries

Answer 17

boundaries between sliding plates, like the San Andreas Fault in the United States

Question 18

Laurasia

Answer 18

one of the two smaller continents created when the supercontinent Pangaea broke apart about 200 million years ago

Question 19

Gondwanaland

Answer 19

one of the two smaller continents created when the supercontinent Pangaea broke apart about 200 million years ago

Question 20

Hotspots

Answer 20

a localised place where an activity occurs

Question 21

Lithosphere

Answer 21

The outer layer of the Earth consisting of the crust and upper mantle

Question 22

Asthenosphere

Answer 22

The upper layer of the Earth’s mantle, where there is relatively low resistance to plastic flow.

Question 23

Mantle

Answer 23

The mantle is the layer of the Earth between the core and the crust. It makes up for nearly 80% of the Earth’s total volume.

Question 24

Core

Answer 24

The core is the central region of the Earth. It consists of two parts: the (solid) inner core and the (liquid) outer core

Question 25

Seismic Waves

Answer 25

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

Question 26

Continental Drift

Answer 26

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

Question 27

Pangaea

Answer 27

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 28

Panthalassa

Answer 28

The vast sea surrounding the supercontinent of Pangaea

Question 29

Tremors

Answer 29

vibration on the Earth’s surface caused by an earthquake

Question 30

Epicircle

Answer 30

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

Question 31

Focus

Answer 31

the point at which an earthquake begins

Question 32

Trianglation

Answer 32

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

Question 33

Seismograph

Answer 33

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

Question 34

Richter scale

Answer 34

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

Question 35

P-waves or Primary waves

Answer 35

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

Question 36

S-waves or Secondary waves

Answer 36

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 37

Body waves

Answer 37

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

Question 38

L-waves or surface waves

Answer 38

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

Question 39

Seismologists

Answer 39

a scientist who studies earthquakes

Question 40

Meltdown

Answer 40

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

Question 41

Volcanoes

Answer 41

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

Question 42

Magma

Answer 42

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

Question 43

Lava

Answer 43

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

Question 44

Volcanic Bombs or Lava Bombs

Answer 44

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

Question 45

Active

Answer 45

describes a volcano that is erupting or has recently erupted

Question 46

Extinct

Answer 46

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

Question 47

Dormant

Answer 47

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