CH 25

Question 1

Mid-Ocean ridge

Answer 1

A system of mountain ranges on the seafloor separated by valleys.

Question 2

Rift Valley

Answer 2

A long, narrow depression.

Question 3

Convergent Plate Boundary

Answer 3

The boundary where two plates collide.

Question 4

Subduction

Answer 4

A process where when a thick and buoyant continental plate meets a thin and dense oceanic plate, the denser plate dives beneath the continent.

Question 5

Divergent Plate Boundary

Answer 5

The boundary between two plates that are moving apart.

Question 6

Transform Plate Boundary

Answer 6

A type of boundary where plates slide horizontally past each other in opposite directions.

Question 7

Earthquake

Answer 7

The sudden movement or vibration of the ground that occurs when rocks slip and slide along enormous cracks in Earth’s crust called faults.

Question 8

Fault

Answer 8

A crack in Earth’s crust along which rock has moved.

Question 9

Elastic Rebound

Answer 9

A sudden release of strain energy as rock moves along a fault.

Question 10

Focus

Answer 10

The point of origin for an earthquake.

Question 11

Epicenter

Answer 11

The point on Earth’s surface directly above the focus.

Question 12

Who came up with the continental drift hypothesis?

Answer 12

Alfred Wegener

Question 13

What were some pieces of evidence that supported Alfred’s hypothesis?

Answer 13

1. Large land animal fossils
2. Coastlines fit together like puzzle pieces
3. Mountain ranges line up and have the same rock composition

Question 14

What was the name of the super continent?

Answer 14

Pangaea

Question 15

Who came up with the Seafloor Spreading Hypothesis?

Answer 15

Harry Hess

Question 16

What did Hess use to help him create a map of the seafloor?

Answer 16

Sonar

Question 17

Who discovered the mid-ocean ridge?

Answer 17

Harry Hess

Question 18

Where will younger rock be located?

Answer 18

Near the MOR

Question 19

What are the three types of plate boundaries?

Answer 19

1. Divergent
2. Convergent
3. Transform

Question 20

Subduction only happens with what kind of plate boundary?

Answer 20

Convergent

Question 21

What are the two types of crust that are involved in plate boundary movement?

Answer 21

1. Oceanic

2. Continental

Question 22

What land forms can form when oceanic crust and continental crust converge?

Answer 22

1. Volcano

2. Deep-sea trench

Question 23

What land forms can be created when two oceanic crusts collide?

Answer 23

1. Hot spots=they create islands

2. Deep-sea trench

Question 24

What land form is created when two continental crusts converge?

Answer 24

Mountains

Question 25

What type of crust must be present for volcanic activity to occur?

Answer 25

Oceanic crust

Question 26

How do divergent plate boundaries move?

Answer 26

They move in opposite directions.

Question 27

What are two examples of divergent plate boundaries?

Answer 27

1. Mid ocean ridge (made up of oceanic crust) | 2. East African Rift (made up of two continental crusts)

Question 28

How do transform plate boundaries move?

Answer 28

They slide by eachother.

Question 29

What is a specific example of a transform plate boundary?

Answer 29

San Andreas Fault. (Two continental crusts

Question 30

How do convection currents work?

Answer 30

1. Magma heats up, becomes less dense, then rises. | 2. Magma cools down, becomes more dense, then sinks.

Question 31

What are the other forces that help with plate movement?

Answer 31

1. Slab pull 2. Ridge push 3. Friction between plates and the mantle

Question 32

What two types of boundaries have shallow earthquakes?

Answer 32

1. Divergent | 2. Transform

Question 33

Which type of plate boundary has deep earthquakes?

Question 34

What are the types of stresses that can be applied to rock?

Answer 34

1. compression 2. tension 3. shear 4. torsion

Question 35

What are the two types of deformation?

Answer 35

1. Elastic | 2. plastic

Question 36

What happens to a rock during elastic deformation?

Answer 36

it deforms and returns to its original shape.

Question 37

What happens to a rock during plastic deformation?

Answer 37

It deforms and stays in that same shape.

Question 38

What are the kinds of seismic waves?

Answer 38

1. Secondary | 2. Surface

Question 39

Which type of seismic wave moves the fastest?

Answer 39

Primary

Question 40

How do primary waves move?

Answer 40

They are compression waves

Question 41

What type of materials do P-waves move through?

Answer 41

Solids and liquids

Question 42

How do secondary waves move?

Answer 42

They are transverse waves.

Question 43

What type of materials do secondary waves move through?

Answer 43

Solids

Question 44

Which type of wave is the most complex and does the most damage?

Answer 44

Surface waves

Question 45

What are the two scales used to measure earthquakes?

Answer 45

1. Richter | 2. Mercalli

Question 46

What does the Richter scale tell us about n earthquake?

Answer 46

The amount of energy released.

Question 47

What does the Mercalli scale tell us about an earthquake?

Answer 47

The amount of damage it causes.