GEOL 102 Historical Geology Final Exam

Detrital sedimentary rocks are those that:

are made up of pre-existing rocks

The asthenosphere is the outer layer of Earth, which is rigid and is broken into individual plates. (True or False)

False

Which of the following best describes the movement along a divergent plate boundary?

Plates are moving away from each other, separating.

Earth's magnetic poles are slightly tilted away from the geographic poles. (True or False)

True

Earth's ____________ is a solid zone that flows plastically.

asthenosphere

Which of the following best describes the movement along a transform plate boundary?

Plates slide perpendicular to each other.

Who was the first person to suggest that all of the continents had originally been joined together as the supercontinent Pangaea?

Alfred Wegener

Hot spots move with continental plates. (True or False)

False

The mechanism for plate movement is:

convection of heat within the mantle

Which of the following best describes the movement along a convergent plate boundary?

Plates move towards each other and collide.

Since its formation 4.6 billion years ago, Earth's layers have always had differences in density and composition. (True or False)

False

Minerals can be both naturally occurring or manmade. (True or False)

False

When the south magnetic poles aligns with the north geographic pole, polarity is considered to be:

reversed

Based on scientific evidence, how old is Earth?

4.6 billion years

Regional metamorphism occurs at ________ plate boundaries.

convergent

The majority of earthquakes and volcanic activity occur along plate boundaries. (True or False)

True

Harry Hess originally proposed the idea of continental drift. (True or False)

False

The smallest layer of Earth, in terms of volume, is the:

crust

The theory of continental drift was quickly accepted by the scientific community. (True or False)

False

No new crust is formed and no old crust is destroyed at _________ plate boundaries.

transform

What explains the formation of our solar system?

the solar nebula theory

The three categories of rocks are classified by ____.

method of formation

Magnetic anomalies in the oceanic crust are _______ and ________ around spreading ridges.

parallel; symmetric

According to the rock cycle:

any rock type can be derived from any other type

Igneous rocks are classified by silica content. (True or False)

True

Terrestrial planets are denser than the Jovian planets. (True or False)

True

Metamorphism taking place adjacent to a body of magma (a pluton) or beneath a lava flow from heat and chemically active fluids is called ____.​

contact metamorphism

The oldest ocean crust is most likely to be found ____.

adjacent to continental margins

Detrital sedimentary rocks form through compaction or cementation, in a process called:

lithification

Magmas are classified based on silica content. (True or False)

True

How many major tectonic plates are there on Earth?

7

What is the study of the origin and evolution of Earth, its continents, oceans, atmosphere, and life?

historical geology

Studies of paleomagnetism document:

how the Earth's magnetic poles have varied through time

Which of the following layers is NOT a part of the lithosphere?

outer core

What occurred 14 billion years ago?

the Big Bang

Which line of evidence was not used by Alfred Wegener to support continental drift?

paleomagnetic data​

Foliation in metamorphic rocks is caused by:

pressure

Molten rock material below the surface of Earth is called ____.

magma

Which division of Earth exists below the crust and above the core?​

mantle

Any rock altered in the solid state from pre-existing rocks by any combination of heat, pressure, and chemically active fluids is a(n) ____ rock.

metamorphic

Which of the following about the Earth's core is true?

the inner core is solid and the outer core is liquid

Igneous rocks formed in Earth's interior are called:

intrusive

Oceanic crust is _________ nearest the continents and _________ near the mid-oceanic ridges.

oldest; youngest

Evidence for the Big Bang includes the ____.

presence of background radiation

Although there are about 3,500 minerals, only about 2 dozen are common. (True or False)

True

The two major disciplines of geology are historical geology and physical geology. (True or False)

True

What mineral group is generally dark in color?

ferromagnesian

The largest layer of Earth, in terms of volume, is the ____.

mantle

Lava is molten rock below Earth’s surface. (True or False)

False

The two types of Earth’s crust are known as lithospheric and oceanic. (True or False)

False​

Nicolas Steno proposed the principle of uniformitarianism. (True or False)

False

A division on the geologic time scale represents ____.

​a distinctive event in the rock record

Which of the following was not among the early attempts to determine Earth's age?

the rate of rainfall and volcanic ash entering the oceans

An unconformity in which stratified sedimentary rocks overlie an erosional surface cut into igneous or metamorphic rocks is called a(n)____.

nonconformity

Which type of radioactive decay occurs when an electron is added to the parent nucleus?

electron capture

The present geologic time scale is based on relative and numerical dating techniques. (True or False)

True

The degree to which detrital particles have had their sharp edges and corners smoothed off by abrasion is ____.

rounding

A break or gap in the geologic record resulting from erosion or nondeposition or both is a(n) ____.

unconformity

Radioactive decay that occurs when two protons and two neutrons are emitted from the parent nucleus:

alpha decay

The skull of a T. Rex is an excellent example of a trace fossil. (True or False)

False

Each division on the geologic time scale represents an equal chunk of time, of 500 million years. (True or False)

False

An erosion surface that overlays rock layers positioned at an angle:

angular unconformity

When minerals replace the bodily remains during fossilization, we say the fossil has been ____.

altered

The principle of ____________ states that fragments of a rock must be younger than the rock layer they are contained within.

inclusions

Which of the following is a trace fossil?

dinosaur footprint

The principle of __________ states that all sediment is deposited in horizontal layers and any tilting or deformation occurred after deposition and lithification.

original horizontality

To ensure accurate radiometric dating, rock samples should be:

fresh, unweathered and not subject to heat or pressure

The principle of ________ states that sediment will continue to extend in all directions until it thins out or terminates against the edge of a basin.

lateral continuity

Deltas form when streams or rivers encounter a standing body of water, such as an ocean or lake. (True or False)

True

William Smith proposed the principle of fossil succession. (True or False)

True

A marine transgression is a period of lower sea level. (True or False)

False

The Mississippi River Delta is what type of depositional environment?

transitional

If the grains in a sedimentary rock are all roughly the same size, we describe that rock as:

well-sorted

Relative dating of geologic events was not possible before the discovery of radioactivity in the late 19th century. (True or False)

False

Remains or traces of prehistoric organisms preserved in rocks are ____.

fossils

Radiometric dating is based on ____.

spontaneous decay of radioactive elements

Assigning a specific date to a rock, which is measured in years before present, is known as ____.

numerical dating

The principle of fossil succession is based on the fact that fossils ____.

succeed one another through time in an order

An erosional surface that separates sedimentary strata that are parallel with one another is called a(n) ____.

disconformity

Change in sea level is most affected by ____.

glacial ice volumes and tectonic activity

The time necessary for one-half of the original number of radioactive atoms of an element to decay to a stable daughter product is known as a(n) ____.​

half-life

Current ripple marks differ from wave ripple marks because ____.

current ripple marks are asymmetrical

Not all fossils contain the direct remains of an organism.​ (True or False)

True

The mosquito from Jurassic Park is an example of a(n):

unaltered body fossil

Depositional environments have unique physical, biologic and chemical processes. (True or False)

True

Species with durable skeletons are more likely to be captured in the fossil record. (True or False)

True

In a sequence of undisturbed sedimentary rocks, the oldest fossils will be ____.

in the bottom rock layer

What principle did James Hutton develop?

the principle of uniformitarianism

The two sedimentary rock compositions are:

detrital; chemical

If the Earth went through another ice age, and glaciers expanded, what would occur?

marine regression

The principle of superposition states that ____.

younger rock layers are found above older rock layers

Sedimentary structures form prior to lithification. (True or False)

True

Which is NOT true about radioactive decay?

it is only used in relative dating techniques

Placing geologic events in a chronological order from their position in the rock record is called ____.

relative dating

The period of time not represented by strata in an unconformity is a hiatus.​ (True or False)

True

At various times during Earth’s history, the western half of the United States has been covered by an inland sea. (True or False)

True

What would occur if all of the ice on Greenland and Antarctica melted?​

marine transgression

What theory proposes that the same processes seen today have operated throughout geologic time (i.e. the present is the key to the past)?

uniformitarianism

A half-life is the amount of time required ____.

for half of the parent atoms to decay to daughter atoms

In a well-sorted rock, ____.

all grains are about the same size