Wk 13 Quiz

Question 1

Earth’s outermost layer of rock

Answer 1

Earth’s crust

Question 2

Small, solid fragments of rock and other materials that are carried and deposited by wind, water, or ice. Examples would be sand, mud, or gravel.

Answer 2

Sediment

Question 3

Rock formed when chemical reactions cement sediments together, hardening them

Answer 3

Sedimentary rock

Question 4

Rock that forms from molten rock

Answer 4

Igneous rock

Question 5

Igneous or sedimentary rock that has been changed into a new kind of rock as a result of great pressure and temperature

Answer 5

Metamorphic rock

Question 6

Rock that behaves like something between a liquid and a solid

Answer 6

Plastic rock

Question 7

Vibration of the earth that results either from volcanic activity or rock masses suddenly moving along a fault

Answer 7

Earthquake

Question 8

The boundary between two sections of rock that can move relative to one another

Answer 8

Fault

Question 9

The point where an earthquake begins

Answer 9

Focus

Question 10

The point on the surface of the earth directly above an earthquake’s focus

Answer 10

Epicenter

Question 11

Scientists often separate the earth into five distinct sections. Name those sections.

Answer 11

atmosphere, hydrosphere, crust, mantle, and core

Question 12

Of the five sections listed in problem 2, which can we observe directly?

Answer 12

atmosphere, hydrosphere, and crust

Question 13

What two regions of the earth does the Moho discontinuity separate? What about the Gutenberg

Answer 13

The Moho separates the crust from the mantle, and the Gutenberg discontinuity separates the mantle from the core. The Lehmann discontinuity separates the inner core from the outer core

Question 14

What is the difference between the ways that igneous rock and sedimentary rock form?

Answer 14

Sedimentary rock is formed when sediments are solidified through chemical reactions. Igneous rock forms when molten rock solidifies.

Question 15

Of the three types of rock discussed in this module, which type starts out a different type of rock?

Answer 15

Metamorphic rock

Question 16

What is unique about the rock in the asthenosphere?

Answer 16

rock behave sometimes like a liquid and sometimes like a solid

Question 17

What is the main thing scientists observe in order to learn about the makeup of the earth’s interior?

Answer 17

Scientists observe seismic waves

Question 18

Which is solid: the inner core or the outer core? Why is it solid when the other is liquid?

Answer 18

The inner core is solid because of pressure freezing

Question 19

Where is the magnetic field of the earth generated?

Answer 19

The magnetic field is generated in the earth’s core

Question 20

What causes the magnetic field of the earth?

Answer 20

The magnetic field is caused by a large amount of electrical flow in the core

Question 21

Give a brief description of the two main theories that attempt to explain the earth’s magnetic field.

Answer 21

The dynamo theory says that the motion of the core is due to temperature differences in the core and the rotation of the earth. This motion causes the motion of electrical charges in the core, which creates electrical current. The rapid-decay theory states that the electrical current in the core started as a consequence of how the earth formed and is decreasing over time

Question 22

What makes the rapid-decay theory more scientifically valid than the dynamo theory?

Answer 22

The rapid-decay theory has been used to accurately predict the magnetic fields of other planets

Question 23

Why is a catastrophe like the worldwide flood in Noah’s time an essential part of earth’s history if the rapid-decay theory is true?

Answer 23

The rapid-decay theory requires a global catastrophe in order to be consistent with the data that indicate the magnetic field of the earth has reversed several times

Question 24

What two reasons make otherwise good scientists ignore the more scientifically valid rapid-decay theory?

Answer 24

The fact that the rapid-decay theory requires a catastrophe like the worlwide Flood and the fact that the rapid-decay theory indicates an earth 10,000 years old or younger

Question 25

Why would life cease to exist without the earth’s magnetic field?

Answer 25

Without the magnetic field, cosmic rays from the sun would hit the earth

Question 26

What are the “plates” in plate tectonics?

Answer 26

The plates are large “islands” of the earth’s lithosphere

Question 27

What can happen when plates collide with one another?

Answer 27

One plate can slide under another and form a trench; the plates can move away from each other, allowing magma to rise and create new crust; the plates can push against each other, causing the crust to fold; or the plates can slide along each other

Question 28

What is Pangaea?

Answer 28

Pangaea is a hypothetical supercontinent that might have existed in earth’s past

Question 29

Why do otherwise good scientists ignore the plate tectonics theory despite the evidence that exists for it?

Answer 29

Some good scientists ignore plate tectonics because it is typically linked to the idea of an earth that is billions of years old

Question 30

What causes earthquakes?

Answer 30

Earthquakes are caused by the motion of rock masses along a fault or by volcanic activity

Question 31

Briefly describe the elastic rebound theory of earthquakes.

Answer 31

In the elastic rebound theory, rock masses moving relative to one another get caught on the rough, jagged edges of the fault that lies between them. The rock masses start to bend as they keep trying to move. At some point, the stress becomes too great, and the moving rock breaks free, causing the rock masses on both sides of the fault to snap back into their original shapes. The resulting vibrations are what we feel as an earthquake

Question 32

A seismologist detects an earthquake that measures 4 on the Richter scale. Later, he detects one that measures 8. How many times more energy does the second earthquake release as compared to the first?

Answer 32

1,048,576 times more energy than the first

Question 33

Name the four kinds of mountains. What is required for the formation of each?

Answer 33

The four types of mountains are: volcanic mountains, domed mountains, fault-block mountains, and folded mountains. Volcanic and domed mountains need magma from the earth’s mantle, fault- block mountains need vertical motion along a fault, and folded mountains need rock masses pushing against each other