Introduction Lecture 2 - Plate Tectonics

Question 1

Describe the Theory of General Relativity

Answer 1

-Deals with gravity
-Links space and time
-Explains the big stuff

Question 2

Describe the Theory of Quantum Mechanics

Answer 2

-Deals with sub-atomic particles and their behaviour
-Explains the very small

Question 3

Describe the Theory of Thermodynamics

Answer 3

-Systems tend towards equilibrium
-Nothing is free (everything requires energy)
-Things tend towards chaos

Question 4

Describe Atomic Theory

Answer 4

-Structure of atoms and how they interact through electron transfer

Question 5

Describe the Theory of Evolution

Answer 5

-Populations are diverse
-Organisms with advantageous traits survive and reproduce
-The advantageous trait trait becomes dominant over time

Question 6

Define the Origin of Plate Tectonic Theory

Answer 6

-Alfred Wegener suggested that continents once fitted together, e.g. same rock types and fossils found on African and South American continents

Question 7

Outline some evidence for Plate Tectonics

Answer 7

-Mid ocean ridges mapped during the Cold War
-Paleomagnetism
-Continental drift

Question 8

Explain how Seafloor-Spreading supports Plate Tectonic Theory

Answer 8

-On the Mid-Atlantic ridge, the further away you get, the older the rocks are
-Therefore the seafloor must be spreading outwards from the ridge

Question 9

Explain how Paleomagnetism supports Plate Tectonic Theory

Answer 9

-Ferous rocks are magnetised by the Earth’s magnetic field
-The magnetism flips every 450,000 years
-Symmetrical stripes in the rock emerge either side of the ridge

Question 10

Describe the first stage of the Wilson Cycle (Super Continent Cyclicity)

Answer 10

-Rifting within a continent splits it

Question 11

Describe the second stage of the Wilson Cycle (Super Continent Cyclicity)

Answer 11

-Rifting creates a new ocean basin and therefore new oceanic crust

Question 12

Describe the thirs stage of the Wilson Cycle (Super Continent Cyclicity)

Answer 12

-Seafloor spreading continues meaning the ocean opens and passive margin cooling results in sediment accumulation

Question 13

Describe the fourth stage of the Wilson Cycle (Super Continent Cyclicity)

Answer 13

-Convergence begins, the oceanic crust is subducted beneath a continent which creates a volcanic mountain belt at the active margin

Question 14

Describe the fifth stage of the Wilson Cycle (Super Continent Cyclicity)

Answer 14

-Terrain accretion welds material to the continent

Question 15

Describe the sixth stage of the Wilson Cycle (Super Continent Cyclicity)

Answer 15

-Eventually the continents collide and orogeny thickens the crust thus forming a new super continent

Question 16

Describe the seventh and final stage of the Wilson Cycle (Super Continent Cyclicity)

Answer 16

-Continent erodes, thinning the crust and the process eventually begins again