The plates interact at the surface in a variety of ways

Question 1

What is the summary of a divergent oceanic oceanic plate margin?

Answer 1

The rising convection current below lifts the lithosphere, producing a mid-ocean ridge

Question 2

What forms along the oceanic oceanic divergent plate margin?

Answer 2

3000m high ridge

Question 3

What is the summary of a divergent continental continental plate margin?

Answer 3

As the plates are torn apart, the plate arch due to convection. It is torn thin by extensional forces, fracturing the plate so that the central area sinks down to form a Rift Valley.

Question 4

What forms along the bottom of divergent continental continental plate margins?

Answer 4

Large lakes - if it drops below sea water then ocean water will seep in

Question 5

What is the summary of convergent oceanic continental plate margin?

Answer 5

The denser oceanic plate plunges beneath the lighter, less dense continental plate. The sub-ducting plate is forced into higher temperatures and begins to melt. Following the theory of convection, some of the magma rises forming batholiths (large pockets of magma) which explains the bulging of the land, other magma forces through building a magma chamber.

Question 6

What is the summary of convergent oceanic oceanic plate margin?

Answer 6

The older, denser oceanic plate is sub-ducted occurs so the plates are depressed into the asthenosphere below

Question 7

What is the summary of conservative plate movement?

Answer 7

The two plates slide past each other, so the relative moment is horizontal. In the San Andreas fault the pacific plate pushes causing the NAP the buckle up, mountains then begin to form.

Question 8

What earthquake activity takes place on a divergent oceanic oceanic plate margin?

Answer 8

Frequent low magnitude earthquakes occur as rock is ripped and stretched.

Question 9

What earthquake activity takes place on a divergent continental continental plate margin?

Answer 9

As the plates are stretched and magma forces into the gaps frequent low magnitude earthquakes occur.

Question 10

What earthquake activity takes place on a convergent oceanic oceanic plate margin?

Answer 10

The pressure created by the friction is released causing the occurrence of high magnitude and frequent earthquakes.

Question 11

What earthquake activity takes place on a convergent continental continental plate margin?

Answer 11

Earthquake activity is frequent and can be high magnitude. Earthquakes occur throughout collision zone where folding occurs.

Question 12

What earthquake activity takes place on a conservative faults?

Answer 12

Earthquakes tend to be the strongest centrally and weaker towards the edge of the fault zone.

Question 13

What volcanic activity takes place on a divergent oceanic oceanic plate margin?

Answer 13

As volcanoes are eventually pulled off ridge they become extinct. In some places the magma may escape/erupt at the surface creating shield volcanoes

Question 14

What volcanic activity takes place on a divergent continental continental plate margin?

Answer 14

As the plate is torn and stretched some magma escapes at surface resulting in volcanoes

Question 15

What volcanic activity takes place on a convergent oceanic continental plate margin?

Answer 15

The magma rises creating magma chambers, eventually it will erupt in the form of an explosive volcano.

Question 16

What volcanic activity takes place on convergent oceanic oceanic plate margins?

Answer 16

The plate melts to form magma, which rises to the top of the overriding oceanic plate and erupts on the ocean floor

Question 17

What volcanic activity takes place on convergent continental continental plate margins?

Answer 17

As theres no subduction or friction in the Benoiff zone, there’s no volcanic activity

Question 18

How might there be a Tsunami threat on an oceanic oceanic convergent plate margin?

Answer 18

As the toe of the plate is down-warped it may result in pressure being released by the toe flicking back towards the oceanic plate resulting in a huge displacement of the water column above creating a Tsunami.

Question 19

What landforms are associated with oceanic oceanic divergent plate margins?

Answer 19

Occasionally volcanoes may portrude the ocean surface creating islands
Mid-atlantic ridge

Question 20

What landforms are associated with continental continental divergent plate margins?

Answer 20

Steep sided valleys

Large lakes

Question 21

What landforms are associated with oceanic continental convergent plate margins?

Answer 21

Fold mountains

Ocean trenches

Question 22

What landforms are associated with oceanic oceanic convergent plate margins?

Answer 22

Volcanic island arcs

Question 23

What landforms are associated with continental continental convergent plate margins?

Answer 23

Large young fold mountains

Question 24

What is an example of volcanoes protruding the surface?

Answer 24

Ascension Islands

Question 25

What is an example of a large lake?

Answer 25

Tanganyika Maldive Kirie Lake

Question 26

What is an example of a steep sided valley?

Answer 26

East African Rift Valley

Question 27

What is an example of young fold mountains?

Answer 27

Himalayas

Question 28

How do hotspots develop?

Answer 28

Concentration of radioactive elements below the crust causes a plume of magma to rise and eat into the plate above
Lava breaks through the surface and active volcanoes form above the spot.
The basaltic lava flows slowly and forms huge but flattish volcanoes, sometimes referred to as ‘shield’ volcanoes

Question 29

What is an examine of a hot spot?

Answer 29

The Hawaiian Islands in the Pacific Ocean

Question 30

Why has the Hawaiian hot spot got a chain volcanoes?

Answer 30

The hot spot is stationary, so as the Pacific plate moves over it, a line of volcanoes is created

Question 31

What are the main landforms associated with plate movements?

Answer 31

Ocean ridges, Rift Valleys, Deep sea trenches, Island arcs, Young fold mountains

Question 32

What is an ocean ridge?

Answer 32

Formed when plates move apart in oceanic areas. The space between the plates is filled with basaltic lava upwelling form below to form a ridge.

Question 33

What is a Rift Valley?

Answer 33

Form when plates move apart in continental areas. Brittle crust drops down between parallel faults to form the valley. An area between two parallel rift valleys forms an upstanding block, known as a Horst.

Question 34

What is a deep sea trench?

Answer 34

Where oceanic and continental plates meet, the denser oceanic plate is forced underneath the lighter continental one. The downwarping of the oceanic plate forms a very deep part of the ocean known as a trench.

Question 35

What are Island arcs?

Answer 35

During subduction, the descending plate melts. Being less dense than the surrounding asthenosphere, it rises to the surface as plutons of magma. Eventually forming volcanoes.

Question 36

What are young fold mountains?

Answer 36

As there is no subduction, the plates move towards each other, giving a buckling effect, forming young fold mountains.

Question 37

What earthquake activity takes place on convergent oceanic continental plate margins?

Answer 37

As the more dense, thinner oceanic plate sub-ducts beneath the lighter, less dense continental plate, the area for which the plates remain in contact creates an extremely high pressure zone (Benioff zone) where earthquakes can take place.

Question 38

Whats so important about the benoiff zone?

Answer 38

The deeper/steeper the Benioff zone, the deeper the focus, the deeper the focus the less energy the earthquake will have as there is greater area to dissipate the waves.
The more shallow/gentle gradient the Benioff zone, the more shallow the focus, the more shallow the focus, the greater energy of the earthquake