Tectonics 1.1

Question 1

What are tectonic hazards?

Answer 1

Threats caused by movement of tectonic plates

Question 2

Where do earthquakes occur?

Answer 2

Edges of tectonic Plates
Intraplate regions

Question 3

Earthquakes found in intraplate regions may be built up by what?

Answer 3

Stress (built up)

Question 4

In Intraplate regions, earthquakes may be related to stress built up by?

Answer 4

Continental Rifting;
Stress transfer (from other regions)

Question 5

Most active volcanoes occur near to?

Answer 5

Plate boundaries;

Question 6

What percentage of volcanoes occur around the ‘Ring of Fire’?

Answer 6

About 75%;

Question 7

Where is the ‘Ring of Fire’ located?

Answer 7

Pacific Ocean;

Question 8

What type of plate boundaries do volcanoes occur at?

Answer 8

Convergent; Divergent

Question 9

Volcanoes can be found at hotspots in the middle of plates.
Name an example.

Answer 9

Hawaii; Central Pacific

Question 10

What percentage of tsunamis occur around the Pacific Ocean?

Answer 10

Over 70%

Question 11

What percentage of Tsunamis occur around the Mediterranean Sea?

Answer 11

15%

Question 12

How many Tsunamis occur around the Caribbean Sea and Atlantic Ocean?

Answer 12

9%

Question 13

How many Tsunamis occur around the Indian Ocean?

Answer 13

6%

Question 14

What are tsunamis caused by?

Answer 14

Tectonic Activity

Question 15

Which type of plate boundary causes the most tsunamis to occur due to their activity?

Answer 15

Convergent boundaries;

Question 16

Three main types of plate boundary?

Answer 16

Convergent;
Divergent;
Conservative;

Question 17

What are the three main earthquake belts?

Answer 17

Pacific;
Mid- Atlantic;
Alphide;

Question 18

Some earthquakes occur away from active plate boundaries- for example old plate boundaries or faults - where weaknesses are; How often are these, relativity?

Answer 18

Rare and low intensity;

Question 19

How many active volcanoes are in the world?

Answer 19

500

Question 20

How many volcanoes erupt each year?

Answer 20

50;

Question 21

There is little scientific data around what type of volcanoes?

Answer 21

Submarine;

Question 22

The most explosive volcanoes are produced from what type of plate boundary?

Answer 22

Convergent;

Question 23

What dissolved gases do convergent volcanoes’ magma have high levels of?

Answer 23

Silicon; Oxygen

Question 24

What do silica rich plates produce?

Answer 24

Silica rich magmas;

Question 25

Where do silica rich magmas come from?

Answer 25

Melted continental crusts;

Question 26

What do earthquakes at divergent boundaries tend to be?

Answer 26

Shallow; Low Magnitude;

Question 27

What do volcanic eruptions tend to be at divergent boundaries?

Answer 27

Small; Effusive

Question 28

What does effusive mean?

Answer 28

Basaltic magma; Becomes lava; Solidifies

Question 29

What type of lava are usually of volcanic eruptions at divergent boundaries?

Answer 29

Basaltic lava;

Question 30

Is there high or low gas content at divergent volcanic eruptions?

Answer 30

Low gas content

Question 31

Does basaltic lava have high or low viscosity?

Answer 31

High Viscosity;

Question 32

Is basaltic lava high or low temperature?

Answer 32

Higher temperature;

Question 33

What zone do friction and pressure build up at convergent boundaries to cause strong earthquakes?

Answer 33

Benioff Zone

Question 34

What do volcanic eruptions tend to be at convergent boundaries?

Answer 34

Volatile

Question 35

Why do volcanic eruptions at convergent boundaries tend to be more volatile?

Answer 35

Magma;Forcing; Surface; Pressure

Question 36

Do volcanic eruptions at convergent boundaries have high or low gas content?

Answer 36

High gas content;

Question 37

Do volcanic eruptions at convergent boundaries have high or low viscosity?

Answer 37

Low viscosity;

Question 38

Are volcanic eruptions at convergent boundaries higher or lower temperature?

Answer 38

Lower temperature;

Question 39

What type of lava do volcanic eruptions at convergent boundaries tend to have?

Answer 39

Rhyolite lava;

Question 40

What do plates do at conservative boundaries to cause a significant amount of pressure?

Answer 40

Stick;

Question 41

What does the sticking of plates at conservative boundaries create?

Answer 41

Pressure; Powerful Earthquakes;

Question 42

Intra-plate volcanism is also known as what?

Answer 42

Hotspot volcanism;

Question 43

Where do Hotspots occur?

Answer 43

Away from plate boundaries;

Question 44

What is the name of the stationary columns of rising magma in the asthenosphere, where hotspots occur?

Answer 44

Mantle Plumes

Question 45

What are stationery mantle plumes?

Answer 45

Columns of rising magma;

Question 46

Where do hotspots occur over?

Answer 46

Stationary magma plumes;

Question 47

What moves over the stationary mantle plume?

Answer 47

Tectonic plate;

Question 48

What does the tectonic plate moving over the stationary mantle plumes cause?

Answer 48

Island Arcs (Hawaii)

Question 49

Which is the oldest island in island arcs formed at hotspots?

Answer 49

Island furthest away from the plume;

Question 50

What type of boundary is Iceland at?

Answer 50

Divergent;

Question 51

How wide is the mantle plume Iceland is located on?

Answer 51

30-50km

Question 52

In Iceland’s 2010 eruption, what grounded planes over a large portion of the Northern Hemisphere?

Answer 52

Volcanic dust;