Earth Science

Question 1

Lithosphere

Answer 1

The rough outer part of the earth, consisting also the upper most of the mantle.

Question 2

Asthenosphere

Answer 2

The upper layer of the earths mantle, located below the lithosphere, plastic flow and convection is thought to occur

Question 3

Core

Answer 3

The core is made primarily of iron and nickel and has two parts, an inner solid core and an outer liquid core

Question 4

Seismic waves

Answer 4

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

Question 5

Continental drift

Answer 5

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

Question 6

Pangaea

Answer 6

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 7

Panthalassa

Answer 7

The vast sea surrounding the supercontinent of Pangaea

Question 8

Plate tectonics

Answer 8

the theory concerning the movement of the continental plates

Question 9

Convection current

Answer 9

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

Question 10

Continental crust

Answer 10

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

Question 11

Oceanic crust

Answer 11

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 12

Boundaries

Answer 12

the edges of tectonic plates

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

Destructive plate boundaries: a convergent boundary where two plates collide

Question 15

Hotspots

Answer 15

a localised place where an activity occurs

Question 16

Mantle

Answer 16

thick layer inside the Earth, below the crust. Most of the mantle is solid rock, although the upper part is molten rock called magma.

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

Tremors

Answer 20

vibration on the Earth’s surface caused by an earthquake

Question 21

Epicentre

Answer 21

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

Question 22

Triangulation

Answer 22

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

Question 23

Seismograph

Answer 23

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

Question 24

Richter scale

Answer 24

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

Question 25

P-waves or Primary waves

Answer 25

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

Question 26

S-Waves

Answer 26

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 27

Body waves

Answer 27

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

Question 28

Surface Waves

Answer 28

(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 29

Seismologists

Answer 29

a scientist who studies earthquakes

Question 30

Meltdown

Answer 30

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

Question 31

Tsunamis

Answer 31

a powerful ocean wave triggered by an undersea earth movement

Question 32

Volcanos

Answer 32

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

Question 33

Magma

Answer 33

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

Question 34

Lava

Answer 34

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

Question 35

Volcanic Bombs

Answer 35

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

Question 36

Extinct volanos

Answer 36

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

Question 37

Active volcanos

Answer 37

describes a volcano that is erupting or has recently erupted

Question 38

Dormant

Answer 38

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