3.1.5.2 Plate Tectonics

Question 1

who was first to notice the jigsaw fit on SA and west africa and when

Answer 1

francis bacon

early 17th century

Question 2

who published the theory of pangea and when

Answer 2

alfred wegener in 1912

Question 3

what two continents did pangea split into

Answer 3

Laurasia

Gondwanaland

Question 4

what evidence is there of pangea

Answer 4

similar rock types and fossils in africa and south america
jigsaw fit
magnetic field pattern in rocks containing iron

Question 5

explain the evidence of the alternating magnetic field pattern in rocks

Answer 5

the reversal of the earths magnetic field meant that new rock at constructive margins would match that of the magnetic field
symmetry around the margin is evidence that the rocks are moving apart

Question 6

which scientist developed the theory ofthe magnetic field pattern in rocks and when

Answer 6

Ewing

1948

Question 7

characteristics of continental crust

Answer 7

up to 70km thick
+1500 million years old
mainly composed of granite, silicone, aluminium and oxygen

Question 8

characteristics of oceanic crust

Answer 8

up to 10km thick
less than 200 million years old
mainly composed of basalt, silicon, magnesium and oxygen

Question 9

what do plates float on

Answer 9

semi rigid asthenosphere

Question 10

what are convection currents caused by

Answer 10

hot material in the deepest part of the mantle rising then cooling and sinking again

Question 11

what is slab pull

Answer 11

the effect of gravity sinking the edge of an oceanic plate into the asthenospher and forms a trench

Question 12

what is ridge push

Answer 12

plates pulling apart so magma rises where it cools and solidifies

Question 13

what is paloemagnetism

Answer 13

the word used to describe sea floor spreading with the evidence of iron particles aligned in the worlds magnetic field

Question 14

what is a divergent/constructive plate margin

Answer 14

crusts move apart to form new crust when magma rises in the gap

Question 15

what is a convergent/destructive/subductive plate margin

Answer 15

when one plate moves under another

Question 16

what do convergent/destructive margins make

Answer 16

mountain ranges, earthquakes, tsunamis and volcanoes

Question 17

what is a transform/conservative plate margin

Answer 17

when plates slide past each other and create earth quakes

lateral sliding

Question 18

example of constructive boundary

Answer 18

mid atlantic ridge, eurasian and north american plates

Question 19

example of destructive boundary

Answer 19

pacific and eurasian

Question 20

example of conservative plate boundary

Answer 20

north american and pacific (california)!!!!!!!