Post-Exam I Quizzes Geology

What term refers to the raise in biodiversity that occurred during the early Paleozoic era?

Cambrian explosion

Which is the most recent era of time- the one that we are currently in?

Cenozoic

Why does differential weathering occur?

Different minerals have different resistances to weathering.

________________ are the longest subdivision of Geologic Time Scale.

Eons

(Q008) Assuming this photo of a fault surface is upright, which statement best describes the sense of movement along the fault?

It is an oblique strike-slip fault with minor dip-slip.

Which of the following is true regarding biochemical chert?

It is made of cryptocrystalline quartz.

Which soil horizon contains the most organic material?

O

"ancient life"

Paleozoic

The time span that lasted the longest was the___________.

Paleozoic

What name did Wegner give his proposed landmass of combined continents?

Pangea

Why does physical weathering speed up the processes of chemical weathering?

Physical weathering produces more surface area for chemical weathering to attack.

During which eon did Rodinia break up?

Proterozoic

(Q017) After an explosive volcanic eruption on an island, the surrounding sea is full of light-gray, floating rock. What must it be?

Pumice

________ commonly serves as a protolith in the formation of phyllite.

Shale

(Q019) Which of the following statements about metamorphic rocks and their characteristic environments is true?

Slate, phyllite, schist, and gneiss are found in areas of continental collision

(Q002) Dipping sedimentary rock layers include a layer of basalt containing xenoliths of the overlying sedimentary rock. Which of the following statements must be true?

The basalt is a sill intruded into older sedimentary rock.

(Q003) In this illustration, which is a correct interpretation of relative ages?

The granite pluton is older than the fault, which is older than the dike.

When a igneous intrusion is found in a layer, what do we know about its age?

The intrusion is younger than the rock

What can be said about a mountain range that is being uplifted at 2 cm/year but is not growing any taller?

The rate of erosion is the same as the rate of uplift.

(Q001) Which of the following is a characteristic of all rocks

They are a collection of minerals of a body of glass

What is the difference in the formation of chalk versus chert?

They are made of different source material

Which animal is often used as an index fossil for identifying Paleozoic strata?

Trilobites

(Q001) Which statement is true according to the rock

Uplift, weathering, burials, and heating/melting can transform one rock type into another

(Q001) What does the term uniformitarianism mean?

We can interpret the processes that formed ancient rock by examining the processes that form similar rock today.

Hydration occurs when minerals

absorb water and expand

(Q001) What do geologists do?

all of the possible answers are correct

(Q006) Which statement(s) is true about igneous rocks?

all of the possible answers are correct

(Q007) What physical characteristics can be used to distinguish individual rock types?

all of the possible answers are correct

(Q015) Which of the following words could be used to describe portions of a rock with a porphyritic texture?

all of the possible answers are correct

What type of unconformity is shown (red arrow) in the attached block diagram?

angular

Dissolution occurs when minerals

are dissolved into water

(Q021) Pillow Basalts

are formed in a submarine environment

Consult the figure below. Compared with low-grade metamorphic rocks, high-grade rocks

are produced at greater temperatures and pressures.

Consult the figure below. The region of thermally metamorphosed rock surrounding a cooled pluton is called a(n)

aureole

Because the velocity of sediment settling (deposition) is positively related to grain size for waterborne sediments, fluvial deposits are more likely than glacial deposits to

be well sorted

Which environment would most likely produce sedimentary deposits characterized by very well-sorted, very well-rounded grains that are nearly pure quartz?

beach

(Q002) Wegener's theory of continental drift took decades to be accepted

because Wegener couldn't explain how continents moved.

(Q010) Magma moves upward toward the Earth's surface

because it is less dense than the surrounding rock

Geologists call individual layers of sedimentary rocks ________, whereas several of them together are called ________.

beds; strata

(Q004) Which of the following is the MOST PRECISE estimate of when the folding occurred?

before the granite pluton intruded, and after intrusion of the sill

Cemented shells of marine organisms form which kind of sedimentary rock?

biochemical

(Q005) The calcite and aragonite minerals that constitute clamshells are examples of which method of mineral formation?

biomineralization

Which of the following lines of evidence does NOT support the theory of continental drift?

birds on the Galapagos Islands

(Q004) Sedimentary rocks form

by grains being cemented together

Broadly, metamorphism involves

changes in mineralogy and texture in response to heat and stress

Precipitation of gypsum due to evaporation of seawater produces which kind of sedimentary rock?

chemical

Lithified detritus (breakdown products of preexisting rocks) forms which kind of sedimentary rock?

clastic

Grains of sediments and fossils in the deep ocean tend to be ___________-sized because of the low amount of energy in the environment.

clay

What type of sediment is typically found in lake bottoms?

clay/mud

Sediments deposited in a beach environment are typically

composed of rounded grains.

Mountain ranges formed along subduction zones are formed, in part, by ___________ in the crust.

compression

The image below shows an outcrop of coarse-grained sedimentary rock. Note the rock hammer for scale. What is the name of this rock type?

conglomerate

What does the wandering of the Earth's poles through time indicate ?

continents move over time

(Q018) Intrusive igneous rocks

cool slowly and are coarse-grained

The accumulation of sediments that are found on top of the Earth's bedrock is known as

cover.

Consult the figure below. Here, distinct internal laminations are inclined at an angle to the boundary of the main sedimentary layers. These are termed

cross beds

(Q014) An igneous rock that has a medium-gray, fine-grained groundmass with large crystals of plagioclase

crystallized at depth from intermediate-composition magma, and then rose to the surface and became a lava flow

Top set, foreset, and bottomset beds are indicative of ________ environments.

delta

Large layers of cross-bedded sand can be indicative of a ____________ environment.

desert

Normal, reverse, and thrust are all examples of ________ faults.

dip-slip

Salt water is the end product of this weathering process.

dissolution

Which of these is NOT one of the components of deformation?

dissolution

Normal faulting is most often associated with mountain building along ___________ boundaries, whereas reverse faulting is generally observed at ___________ boundaries.

divergent; convergent

When limestone becomes chemically altered, so that half of the calcium atoms are replaced by magnesium, the resultant rock is termed

dolostone

The point on the Earth's surface directly above the point where an earthquake occurs is termed the

epicenter

The presence of metamorphic rocks exposed today at the Earth's surface tells us that _______ has occurred.

erosion

The removal of detritus from weathered rock at an outcrop is termed

erosion

Movement along faults often produces a rock formed from sharply angled rock fragments termed ________.

fault breccia

The distinction between joints and faults is that ________.

faults are fractures along which displacement has occurred; displacement does not occur along joints

What is term for a fold in which layers bend without changing thickness, indicating slip between layers during folding?

flexural slip fold

Slaty cleavage, schistosity, and compositional banding are all examples of

foliation

(Q008) The texture produced when minerals within a metamorphic rock are layered parallel to each other, as shown by the red line, is called

folliation

Hornfels facies rocks form in shallow crustal environments due to contact (thermal) metamorphism. As a result, hornfels typically

form at low pressures and high temperatures

What type of weathering are you most likely to find occurring in areas with cold climates?

frost wedging

(Q005) Metamorphic rock

has changed physical characteristics while remaining solid.

(Q002) Geology

helped determine that the planet existed long before humans did.

Under which of these conditions would a body of rock be more likely to exhibit plastic behavior?

high temperature

(Q004) Which of the following chemical reactions breaks down feldspars into clay?

hydrolysis

Consult the figure below. Hot water reacting with the crust is the basis for what type of metamorphism?

hydrothermal

Which transport medium carries the largest particles?

ice in glaciers

A body of gneiss is subjected to heat and forms a melt. Later, the melt cools and crystallizes to form a(n) ________ rock.

igneous

Thermal (contact) metamorphism occurs

in areas surrounding igneous intrusions

The majority of the Earth's mountains occur ________.

in belts called orogens

(Q003) The rock cycle indicates that

input of new melt into the crust enters the rock cycle as an igneous rock.

(Q003) There is no rock record for the Earth's first 500 million years because

intense meteorite bombardment may have destroyed most land surface.

Chemical weathering involves the breakdown of material due to

interaction with water or air

Which types of minerals are most likely to experience oxidation during chemical weathering?

iron minerals such as biotite and pyrite

(Q004) The crystallization of salt from evaporating seawater

is an example of precipitation from a solution.

Regional metamorphism

is another name for dynamothermal metamorphism

regional metamorphism

is another name for dynamothermal metamorphism

(Q002) A crystalline rock

is composed of interlocking minerals that grew together

(Q003) Oceanic crust

is covered by a thin blanket of sediment that thickens away from the ridge axis.

(Q016) Granite

is felsic in composition

(Q017) The geothermal gradient

is the rate of change in temperature with depth within the Earth.

(Q001) The Hadean Eon

is the span of time between the formation of the Earth and the age of the oldest known rocks

What type of phenomenon is demonstrated by the vertical lines in this picture?

jointing

What type of weathering has created the onion-like layers in the rocks in the below picture?

jointing

(Q003) Natural cracks in rock that form due to exhumation of deeply buried rock are called

joints

(Q019) In which tectonic setting would you most expect to find igneous activity?

landward of oceanic tranches

Differential weathering occurs when

layers of rock weather at different rates

________ commonly serves as a protolith in the formation of marble.

limestone

Compaction and cementation of grains occurs during

lithification

Which of the following best describes the term sediment?

loose fragments of rocks and minerals broken off bedrock or precipitated from water

Under which condition would a body of rock be most likely to exhibit brittle behavior?

low temperature

Around the world, compass needles tend not to point to geographic north. What is the angle between where the compass points and longitudinal lines called?

magnetic declination

A protolith

may belong to any of the three primary rock types

(Q005) The first life forms

may have been simple cells of bacteria or archaea living near hydrothermal vents.

A buried body of shale is subjected to differential stress, causing clay minerals to realign and produce slate. This is an example of

metamorphism

If compressive stresses acting on a rock are greatest in a north-south direction, the rock will likely deform by shortening in a _________ direction.

metamorphism

The gain and loss of chemical elements in a metamorphic rock induced by a reaction with hot groundwater is termed

metasomatism

Chemical sedimentary rocks are classified primarily on the basis of

mineral composition

Foliated metamorphic rocks possess

mineral grains in preferred orientations or patterns of association (banding)

The zone of leaching is the area in which

minerals are dissolved and removed from soil

minerals are dissolved and removed from soil

minerals are dissolved and removed from soil.

Sedimentary rocks are most likely to form

near Earth's surface

During metamorphism, new mineral grains can form that are not found in the protolith. This process is called _________.

neocrystallization

Thermal (contact) metamorphism produces

nonfoliated rocks only

Clay minerals within a buried body of slate are recrystallized at high temperatures and pressures to form mica, producing a rock called phyllite. This is an example of

normal

Which type of a fault is the result of deformation to accommodate tensile stresses such as those that occur during rifting?

normal

If compressive stresses acting on a rock are greatest in a north-south direction, the rock will likely deform by shortening in a _________ direction.

north-south

On a geologic map, the beds of an eroded anticline will be _________ near the fold hinge compared to further from the hinge.

older

Two major sources of energy, coal and oil shale, are considered ________ sedimentary rocks.

organic

An episode of mountain building is termed a(n) ________.

orogeny

Which type of weathering process is happening to materials when they rust?

oxidation

(Q007) The various geologic settings in which rocks can melt, metamorphose, or become sediment are ultimately generated by

plate tectonics

The primary difference between breccia and conglomerate is that conglomerate

possesses more rounded grains than breccia.

Surface waves

produce most of the damage to buildings during earthquakes

The preexisting rock that is subsequently altered to form a metamorphic rock is termed a

protolith

(Q013) Which of the following terms has to do with extrusive igneous activity

pyroclastic

Two common metamorphic rocks that typically lack foliation are ________ and ________.

quartzite; marble

During metamorphism, small mineral grains can reform into larger, interlocking grains of the same mineral. This process is called _________.

recrystallization

If a fault plane is greater than 30° from horizontal and the hanging wall block moves upward relative to the footwall block, the fault is called a ________ fault.

reverse

Dynamothermal (regional) metamorphism occurs when

rock becomes deeply buried during continental collision and mountain building

Which of the following is a type of physical weathering?

rocks breaking apart into smaller pieces along joints and other fractures

What type of weathering are you most likely to find occurring near an ocean?

salt wedging

What type of weathering has produced the honeycomb-like features shown in the following photo?

salt wedging

________ commonly serves as a protolith in the formation of quartzite.

sandstone

The energy that is released during an earthquake travels through the Earth as vibrations termed _______.

seismic waves

(Q010) A petrographic microscope

sends transmitted polarized light through a thin section of rock

________ commonly serves as a protolith in the formation of slate.

shale

Limestone is most likely formed in which of the following environments?

shallow-marine carbonate

(Q002) Which of the following might be considered sediment?

shell fragments washed up on a beach

Regions where Precambrian metamorphic rocks are exposed at the surface are termed ________.

shields

A body of rock affected by compressive stress will likely undergo ________.

shortening

Which list properly orders foliated metamorphic rocks from lowest to highest grade from left to right?

slate, phyllite, schist, and gneiss

Many features of the ocean floor became apparent after extensive mapping by sonar during World War II. Which feature of the ocean floor was not identified at that time?

slicken lines

A polished surface produced by scraping of rock along a fault is termed a(n) ________.

slickeside

Ripple marks are ________

small, elongate ridges in clastic sediments and rocks that form perpendicular to the direction of flow.

Weathering results in

smaller, more rounded pieces

The Dust Bowl of the 1930s is an example of what hazard to soils and the roles they play in society?

soil erosion

Climate, substrate, slope, time, and organisms are all factors that influence _______.

soil formation

(Q004) During World War II, the military imaged the seafloor by sending pulses of sound waves down through the water and measuring the time it took for the sound to bounce off the seafloor and return to the receiver. This method is called

sonar

Which of the following is NOT an example of deformation?

stratification

A body of rock affected by tensile stress will likely undergo ________.

stretching

The statement that the oldest layer will be at the bottom in an undisturbed sequence of rock layers is called the Principle of ____________________.

superposition

What is a contact aureole?

the belt of metamorphosed rocks surrounding an igneous intrusion

Stratification refers to

the development of layering within sedimentary rocks

A geologist found a layer of sandstone with a 400 million year old trilobite in it. Laying below is a layer of metamorphic rock. Which of the following must be true?

the metamorphic rock must be at least 400 million years old.

(Q003) The genetic scheme for classifying rocks is based on

the origin of formation

The transformation of protoliths into metamorphic rocks solely through transfer of heat is termed ________ metamorphism.

thermal

Grains become rounded primarily during

transportation

A mineral-filled crack in a rock is termed a _______.

vein

If water is the transport mechanism of sediment, the grain size of sedimentary deposits most closely indicates the

velocity of the water at the moment the sediment settled to the bottom

If a geologist found preserved mud cracks, they could conclude that the environment in which they formed

was once covered in wet mud

Sediment formation is the result of __________ at the Earth's surface.

weathering

The breakdown of exposed rock into small fragments and dissolved ions is termed

weathering

The process by which running water, wind, or ice carry away bits of broken-up rock is known as ________________.

weathering

What 2 things make a good index fossil?

widespread and a short geologic time

It is unusual for ________ to carry grains larger than sand.

wind

About how much of Earth's history is made up of the Cenozoic time?

1.4%

(Q001) Modern plate tectonic theory was developed in what decade?

1960s

(Q004) This diagram shows an example of how rocks can change in the rock cycle. Which of the following property defines the numbered processes?

1: weathering, transport, and deposition; 2: burial and heating; 3: melting

The image below shows a series of graded beds. How many graded beds are shown?

3

(Q003) When did the Earth form?

4.58 Ga

How long ago did the dinosaurs become extinct?

66.5 Ma

About how much of Earth's history is made up of the Paleozoic time?

7%

(Q009) Which of the following statements about observing rocks at an outcrop is true?

A hand specimen is a small piece of the outcrop that can be examined closely

Which letter corresponds to the regolith in the following picture?

A or B

(Q009) Identify the statement that is true about soil-forming factors

A young soil in an arid climate will be thinner than an old soil in a temperature climate

(Q001) Identify the true statement

About 6 million years ago, the African Plate moved northward and collided with eh European Plate to create a dam between the Atlantic Ocean and the Mediterranean Sea.

(Q002) Which of the following was a component of the Earth's Hadean atmosphere?

Ammonia

What was the worlds first super-predator?

Anomalocaris

(Q004) Which geologic time interval saw the first continents, the first life, and possibly the first plates?

Archean

Why are earthquakes on continents most likely to occur above the brittle-plastic transition depth?

Below the transition, the rocks respond to stress by changing shape without breaking

Which soil horizon contains weathered bedrock that has NOT yet undergone leaching?

C