Plate Tectonics & Surface Changes

Question 1

Where does Earth’s magnetic field originate?

Answer 1

Outer core

Question 2

The Earth’s outer core is composed mainly of:

Answer 2

Iron and nickel

Question 3

What causes the Earth’s magnetic field?

Answer 3

Moving metallic fluid in the outer core

Question 4

The lithosphere is divided into:

Answer 4

A small number of rigid plates

Question 5

What lies beneath the lithosphere?

Answer 5

Asthenosphere

Question 6

Oceanic plates are composed mainly of:

Answer 6

Mafic rocks

Question 7

Continental plates are composed mainly of:

Answer 7

Felsic rocks

Question 8

Average density of oceanic plates:

Answer 8

3200 kg/m³

Question 9

Average density of continental plates:

Answer 9

2600–2750 kg/m³

Question 10

Which is thicker, oceanic or continental crust?

Answer 10

Continental

Question 11

The oldest oceanic rocks are less than:

Answer 11

200 million years old

Question 12

The oldest continental rocks may be as old as:

Answer 12

4 billion years

Question 13

How many main types of plate boundaries exist?

Answer 13

Three

Question 14

A boundary where plates move apart is called:

Answer 14

Divergent

Question 15

A boundary where plates move toward each other:

Answer 15

Convergent

Question 16

A boundary where plates slide past one another:

Answer 16

Transform (Conservative)

Question 17

At which boundary is the new crust created?

Answer 17

Divergent

Question 18

What geological feature is typical of divergent boundaries?

Answer 18

Mid-ocean ridges

Question 19

What process explains the creation of a new oceanic crust?

Answer 19

Seafloor spreading

Question 20

What happens to one plate during subduction?

Answer 20

It descends into the mantle

Question 21

At what depth does a subducting plate begin to melt and form magma?

Answer 21

160 km

Question 22

Which boundary produces the largest earthquakes and volcanic activity?

Answer 22

Convergent

Question 23

When oceanic and continental plates collide, which one subducts?

Answer 23

Oceanic plate

Question 24

What feature forms at a convergent boundary between oceanic and continental plates?

Answer 24

Volcanic arc

Question 25

The Andes Mountains are an example of which type of boundary?

Answer 25

Oceanic–continental convergence

Question 26

The collision of two oceanic plates forms:

Answer 26

Island arcs

Question 27

Example of oceanic–oceanic collision:

Answer 27

Japanese Island Arc

Question 28

The collision of two continental plates results in:

Answer 28

Mountain building

Question 29

The Himalayas formed from:

Answer 29

Continental–continental collision

Question 30

What happens to the lithosphere at conservative boundaries?

Answer 30

Neither created nor destroyed

Question 31

The San Andreas Fault is an example of which boundary?

Answer 31

Conservative

Question 32

Which natural disasters are caused by movement along faults?

Answer 32

Earthquakes

Question 33

Where do most earthquakes occur on Earth?

Answer 33

At plate boundaries

Question 34

The deepest earthquakes occur at:

Answer 34

Subduction zones

Question 35

The deepest earthquakes can reach depths of about:

Answer 35

670 km

Question 36

Shallow earthquakes are found mostly at:

Answer 36

Divergent boundaries

Question 37

Tsunamis are typically generated by:

Answer 37

Earthquakes at subduction zones

Question 38

What was the magnitude of the 2004 Aceh, Indonesia tsunami earthquake?

Answer 38

7.0+

Question 39

Tsunami waves are caused by:

Answer 39

Sea floor uplift

Question 40

Malaysia experiences fewer earthquakes because:

Answer 40

It lies far from active plate boundaries

Question 41

What was the magnitude of the 2015 Sabah earthquake?

Answer 41

6.0

Question 42

Which geological process forms mountains in the long term?

Answer 42

Folding and faulting

Question 43

What are some catastrophic surface process?

Answer 43

Volcanic eruption Tsunami Rock slide

Question 44

Coastal erosion in Miri progresses about:

Answer 44

1 m/year

Question 45

What is a rock slide?

Answer 45

Downward collapse of rock masses along a plane of weakness

Question 46

The Earth’s magnetic field is generated because:

Answer 46

The outer core acts like a dynamo due to moving metallic fluid

Question 47

The lithosphere moves over which layer?

Answer 47

Asthenosphere

Question 48

The oceanic crust is younger than continental crust because:

Answer 48

It is constantly being recycled at subduction zones

Question 49

Divergent boundaries are also known as:

Answer 49

Constructive boundaries

Question 50

The Himalayas are still rising today because:

Answer 50

The Indian and Eurasian plates continue to collide

Question 51

A transform boundary is also known as a:

Answer 51

Sliding or conservative boundary

Question 52

Deep-focus earthquakes (greater than 300 km) occur mostly:

Answer 52

In subduction zones

Question 53

The 2004 Indian Ocean tsunami was caused by:

Answer 53

Earthquake at a convergent margin near Indonesia

Question 54

Malaysia lies within an intra-continental region with low seismic activity

Answer 54

True

Question 55

Why are catastrophic events like landslides or volcanic eruptions still considered “regular” in geological time?

Answer 55

Over millions of years, they form part of normal Earth processes