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Flashcards in Tectonic Hazards Deck (33):
1

The Mantle

A zone of molten silicates and other minerals

2

Examples of tectonic plates

Eurasian, Oceanic, North American

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The Two types of Crust

Oceanic- dense, thinner, newer

Continental- less dense, thicker, older

4

Convection currents

Heat currents in the molten magma that move the crust above very slowly

5

Outer core

Slightly less pressure

6

Solid core

Made of Iron and nickel which is solid despite temperatures of 3700 degrees because of intense pressure there

7

What is a Conservative plate boundary

A plate margin where two tectonic plates slide past each other

8

What is a constructive plate boundary?

Tectonic plate margin where rising magma adds new material plate that are diverging or moving apart

9

What is a destructive plate boundary?

Tectonic plate margin where two plates are converging or coming together and oceanic plate is subducted.

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What are destructive plates associated with?

Violent earthquakes and explosive volcanoes

11

What is an example of a constructive plate margin?

In the Mid Atlantic Ridge where the Eurasian plate is moving away from the North American plate

12

What is a Subduction zone?

Where the heavier (denser) Oceanic plate is pushed beneath the less dense Eurasian plate.

13

Features found in a Subduction zone

Fold Mountains, Volcanoes, trenches, earthquakes

14

What is an example of a destructive plate margin?

Along the West coast of the America and Japan where the Philippines sea plate is pushed under the Eurasian plate.

15

What occurs at a conservative plate margin?

Earthquakes due to a release of stress energy which releases shock waves.

16

What is an example of a conservative plate margin?

The San Andreas Fault in California where the Pacific plate is moving north west faster than the North American plate

17

What do destructive plate margins create?

Earthquakes and volcanoes

18

What do constructive plate margins create?

Volcanoes

19

What do conservative plate margins create?

Earthquakes

20

What are volcanoes created by?

The intrusion of magma into the earth's crust and by the eruption of that magma onto the earth's surface through a vent

21

What are active volcanoes?

The constantly erupting volcanoes are active

22

Give an example of an active volcano

Stromboli on an island near Italy

23

What are intermittent volcanoes?

They erupt at fairly regular time periods

24

An example of an intermittent volcano

Mount Etna in Italy

25

What are in-active volcanoes?

Volcanoes that haven't erupted since the beginning of recorded history meaning they are extinct

26

What do shied volcanoes extrude?

Huge quantities of basaltic lava that gradually build a wide mountain with a shield-like profile

27

Example of a shield volcano

Mauna Loa is the biggest shield volcano on earth and rises over 9000m from the ocean floor and forms part of Hawii

28

What are composite or strato volcanoes?

Tall, steep sided conical mountains composed of lava flows and other materials in layers, these layers (strato) give rise to the name.

29

An example of composite volcanoes

Mt. Fuji in Japan where the lava is thick and sticky

30

What are volcanoes made up of?

Several layers of dust, ash, blast material and lava

31

What is a vent?

An opening through which magma escapes

32

What are earthquakes?

Vibrations in the earth's crust that creates shaking at the surface

33

Reasons for earthquakes

Stress build up due to plates passing each other
As they pass they snag and grind causing a build up of energy