Exam 12-11-18

Question 1

Define plate

Answer 1

A piece of crust

Question 2

Define the Theory of Plate Tectonics

Answer 2

Theory that explains the formation/movement of the Earth’s crust

Question 3

Define lithosphere

Answer 3

The outermost solid part of the crust.

Question 4

The lithosphere is ________ but broken into _______.

Answer 4

solid, pieces

Question 5

The composition of the lithosphere is like that of ______.

Answer 5

basalt

Question 6

Because granite is ______ dense than basalt, continents _______ on top of the lithosphere.

Answer 6

more dense, float

Question 7

Define asthenosphere

Answer 7

The partially melted part of the mantle that contains convection currents that move the crustal plates.

Question 8

Label the diagram

Answer 8

Circular arrows - convection currents, left 2 surface arrows - moving apart, right two surface arrows - moving towards, circular arrows moving towards the surface - expands and rises, circular arrows moving away from the surface - cools and sinks

Question 9

How do plates move where convection currents are rising?

Answer 9

Plates move away from each other when currents are rising.

Question 10

How do plates move where convection currents are sinking?

Answer 10

Plates move towards each other when currents are sinking.

Question 11

Define the theory of the Continental Drift and who proposed this theory?

Answer 11

Wegener’s theory of that says all of today’s continents were once part of one supercontinent which broke apart and the continents then moved into their present positions

Question 12

List some of Wegener’s evidence

Answer 12

Rocks, mountains, glaciers, continental shape, fossils, climate

Question 13

Why do earthquakes and volcanoes occur at plate boundaries?

Answer 13

Earthquakes and volcanoes occur on plate boundaries because that’s where massive amounts of energy are released where the broken edges move against each other

Question 14

Where is the largest area of active earthquakes and volcanoes in the world?

Answer 14

Pacific Plate edges = Ring of fire = most active earthquake and volcano region in the world

Question 15

What is the pattern of magnetic polarity reversal?

Answer 15

Pattern of magnetic polarity = reversals of polarity “recorded” in the rock, and identical on each side of the rift valley

Question 16

What does seafloor spreading have to do with have to do with the Theory of Continental Drift?

Answer 16

Seafloor spreading shows how the plates can push away from each other and make one ocean larger each year, moving the continents on the plates farther away from each other.

Question 17

How are plates moving at diverging boundaries? What else is this called? What two features occur at mid-ocean ridges.

Answer 17

Diverging = moving apart, Seafloor spreading, rift valley and ridge volcanoes