Deck 3: The Solid Earth

Question 1

An atom having either a positive or negative electrical charge is called a(n):

A) molecule.
B) electron.
C) ion.
D) isotope.
E) plasma.

Answer 1

ion.

Question 2

A variety of an element that is heavier than normal because of the presence of extra neutrons is called a(n):

A) molecule.
B) electron.
C) ion.
D) isotope.
E) heavy atom

Answer 2

isotope.

Question 3

Most of the mass of an atom is located in its:

A) protons.
B) electrons.
C) outer orbits.
D) nucleus.
E) ions.

Answer 3

nucleus.

Question 4

Which of the following is NOT part of the general definition of a mineral?

A) narrow range of chemical composition
B) crystalline character
C) inorganic
D) naturally occurring
E) amorphous

Question 5

Most of the rocks of the Earth's crust are made up of which of the following mineral groups?

A) silicates
B) oxides
C) carbonates
D) tungstates
E) vanadates

Question 6

Which silicate mineral is the most abundant in the Earth's crust?

A) basalt
B) feldspar
C) obsidian
D) magnetite
E) calcite

Question 7

Which property of minerals is variable and therefore the least reliable as a clue in identifying a mineral type?

A) color
B) cleavage
C) hardness
D) crystal form
E) luster

Question 8

What is the name of an aphanitic rock consisting of 50% pyroxene, 20% plagioclase feldspar, 20% olivine and 10% hornblende?

A) Andesite
B) Basalt
C) Gabbro
D) Diorite
E) Granite

Question 9

Granite is a type of:

A) volcanic rock.
B) metamorphic rock.
C) intrusive igneous rock.
D) extrusive igneous rock.
E) sedimentary rock.

Question 10

What is a common distinguishing characteristic of sedimentary rock masses?

A) They tend to be extremely hard.
B) They are always very colorful.
C) They are formed by solidification from a melt.
D) They tend to be layered.
E) all of the choices

Question 11

Judge the following sentence according to the criteria given below: Accretionary terrains are much less likely to develop around the margins of the Atlantic Ocean than the Pacific BECAUSE the Pacific Ocean is much larger in area than the Atlantic.

A) The assertion and reason are both correct, and the reason is valid.
B) The assertion and reason are both correct, and the reason is invalid.
C) The assertion is correct and the reason is incorrect.
D) The assertion is incorrect and the reason is correct.
E) Both the assertion and the reason are incorrect.

Question 12

What would be the method of choice for dating an organic substance less than 100,000 years old?

A) uranium-238
B) potassium-40
C) rubidum-87
D) carbon-14
E) europium-123

Question 13

Australia's famous Uluru (Ayer's Rock) is what type of rock?

A) igneous rock
B) asthenospheric rock
C) sedimentary rock
D) mantle lid rock
E) metamorphic rock

Question 14

Which of the following is a type of plate boundary where new seafloor is formed?

A) divergent
B) convergent
C) emergent
D) passive
E) transform

Question 15

At what type of plate boundary do compression and subduction take place?

A) divergent
B) convergent
C) emergent
D) passive
E) transform

Question 16

What force is thought to be an important cause of plate tectonic motion?

A) Earth tides
B) earthquakes
C) thermal convection currents
D) shear strain
E) volcanic eruptions

Question 17

What type of plate boundary is the San Andreas Fault?

A) convergent
B) divergent
C) transform
D) passive
E) none of the choices

Question 18

Which of the following countries is the locality of the oldest know intact terrestrial rocks?

A) China
B) Australia
C) Brazil
D) Canada
E) Sweden

Question 19

What does a Benioff-Wadati zone refer to?

A) an area of extensional stress
B) a subduction zone
C) a transform plate boundary
D) an area of high heat flow
E) an area lacking deep earthquakes

Question 20

Which statement below is true about oceanic crust in comparison to continental crust?

A) Oceanic crust is thinner and heavier (higher specific gravity).
B) Oceanic crust is thicker and heavier (higher specific gravity).
C) Oceanic crust is thinner and lighter (lower specific gravity).
D) Oceanic crust is thicker and lighter (lower specific gravity).
E) Oceanic crust is heavier and has about the same thickness.

Question 21

Oxygen and silicon alone comprise 75% of crustal rocks by weight.

Question 22

About 20 out of the thousands of known mineral species make up the bulk of the Earth's crust.

Question 23

In comparison to white asbestos, blue asbestos is the less harmful type used for industrial purposes.

Question 24

Rapid cooling of molten rock produces large crystals.

Question 25

Rocks such as basalt, on the right side of the igneous rock classification, are darker-colored and have higher specific gravity than do rocks such as granite, on the left side.

Question 26

Metamorphic rocks where minerals have been flattened into layers by directed pressure are said to be foliated.

Question 27

Relative age dating enables scientists to determine the age in years of a rock mass, whereas absolute age dating can only determine the sequence of events.

Question 28

Rock layers containing extensive fossils of organisms with hard parts represent only about 12% of geologic time.

Question 29

In five half-lives, one-sixteenth of a radioactive substance will remain.

Question 30

Dates on zircons from Western Australia suggest that the oldest crustal rocks are more than 4 billion years old.

Question 31

The earliest evidence of life on Earth is over 3 billion years old.

Question 32

The crust of the Earth is thickest under mountain ranges and thinnest in oceanic areas.

Question 33

The lithospheric plates are thought to move primarily as the result of thermal conduction.

Question 34

Transform plate boundaries are places where shear stresses dominate.

Question 35

The Earth's magnetic field has reversed itself many times in the geologic past.

Question 36

The oldest ocean floor is less than 200 million years old.

Question 37

Sea-floor spreading happens at a rate of several meters per year.

Question 38

People living along a passive margin have a low probability of experiencing volcanoes and earthquakes.

Question 39

There are 70 major plates that cover the outer surface of the Earth.

Question 40

Volcanic mountain ranges and deep earthquakes are common features of continental-oceanic convergent plate boundaries.

Question 41

Explain, in the context of the rock cycle, how a metamorphic rock can become sedimentary rock again.

Question 42

Why do you think the geological time scale is usually not drawn to scale when shown on a single page of a book?

Question 43

Consider the table in the chapter listing the various silicate structures of common rock-forming minerals. Determine the silicon to oxygen ratio for each type and express it as a decimal fraction. This can be done by dividing the number of silicon atoms by the number of oxygen atoms. In the first category (isolated tetrahedral), for example, the ratio is 1:4 or 0.25. What can you conclude from this?

Question 44

How do the continents move in plate tectonics without being broken up by the stresses involved?

Question 45

What distinguishes the lithosphere from the asthenosphere?

Question 46

Contrast the difference in the volume of ice at the south pole versus the north pole. Which has more? Why?

Question 47

What is the significance of the alignment of seamounts and islands of the Hawaii-Emperor Seamount chain and other similarly oriented alignments to the south (e.g., Tuamotu Islands and Line (Austral) Islands)?

Question 48

What are the forces that are thought to cause movement of lithospheric plates in plate tectonics?

Question 49

What would the world be like if plate tectonics was not happening?

Question 50

Explain how the rock cycle relates to the theory of plate tectonics.