Earth -Plate Tectonics

Question 1

Who was continental drift proposed by?

Answer 1

Independently by Alfred Wegener and Frank Taylor

Question 2

What was continental drift originally based on?

Answer 2

Rare fossils, American-European-African contnents and mountain belts fitting together.

Question 3

What is the flow of mantle convective currents?

Answer 3

Upward moving arms reach the lithosphere, move along it, cooling as they go, eventually sinking back to the interior

Question 4

Paleomagnetism

Answer 4

This studies ancient mole positions, using remanant magnetization to reconstructs direction and strength of geomagnetic field in the past.

Question 5

How do underwater volcanoes form?

Answer 5

Upward currents penetrate the lithosphere

Question 6

What is the basis of paleomagnetism?

Answer 6

Iron oxide in igneous rocks which is highly magnetic

Question 7

Curie point

Answer 7

This is the temperature a material loses its ferroelectric and piezoelectric behaviour

Question 8

Ferroelectric

Answer 8

Materials exhibiting spontaneous electrical polarisations, switchable by external electric fields.

Question 9

Piezoelectric

Answer 9

Materials developing electric charges in response to applied mechanical stress respectively.

Question 10

How does paleomagnetism infer past magnetic fields?

Answer 10

Magnetite in erupted lava, cooled to the curie point, are fixed to their orientation towards Earths magnetic field.

Question 11

Earth magnetic field fluctiation

Answer 11

It reverses every 70 million years, a north-point compass would point south bound 70 million years ago

Question 12

Divergent Plate Boundaries

Answer 12

Effusive basaltic volcanism where new crusts are formed

Question 13

Convergent Plate Boundaries

Answer 13

This is where lithosphere is overriden bty another, pushed into the asthenosphere in subduction

Question 14

Example of Divergent and Convergent structures

Answer 14

San Andreas fault and Alps and Himalayas respsectively

Question 15

What causes tectonic plate movement?

Answer 15

Convection cells, where deep heat is brought from core to the Earth surface

Question 16

Mid-Ocean Ridges

Answer 16

These are the centres where the lithosphere is created.

Question 17

Transform Faults

Answer 17

A plate boundary where relative motion between two plates is parallel, sliding against one another.

Question 18

What results from divergent plate boundaries?

Answer 18

Rift zones and transform faults

Question 19

What result from convergent plate boundaries?

Answer 19

Subduction and Volcanism
Mountain building
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