Question 1

Which of the following is true of the geologic column?

Accepted Answer

A)  It is the complete record of the Earth's history that is preserved in the rocks at any given location. 
B)  It portrays the spatial distribution of rock units at the Earth's surface. 
C)  It is a composite stratigraphic column created by correlating strata from millions of locations around the world. 
D)  It is an interval of strata composed of a specific rock type or group of rock types that together can be traced over a broad region. 
A)  It is the complete record of the Earth's history that is preserved in the rocks at any given location. 
B)  It portrays the spatial distribution of rock units at the Earth's surface. 
C)  It is a composite stratigraphic column created by correlating strata from millions of locations around the world. 
D)  It is an interval of strata composed of a specific rock type or group of rock types that together can be traced over a broad region.

Question 2

The surface below sedimentary rocks that overlie igneous or metamorphic rocks is termed a(n)

Accepted Answer

A)  disconformity. 
B)  angular unconformity. 
C)  nonconformity. 
D)  marker bed. 
A)  disconformity. 
B)  angular unconformity. 
C)  nonconformity. 
D)  marker bed.

Question 3

Accurate radiometric dating typically requires that a rock contains a measurable amount of

Accepted Answer

A)  parent isotope atoms. 
B)  daughter isotope atoms. 
C)  either parent or daughter atoms. 
D)  both parent and daughter atoms. 
A)  parent isotope atoms. 
B)  daughter isotope atoms. 
C)  either parent or daughter atoms. 
D)  both parent and daughter atoms.

Question 4

The oldest geologic unit is

Accepted Answer

A)  Layer 1. 
B)  Layer 8. 
C)  Layer 5. 
D)  Layer 10. 
A)  Layer 1. 
B)  Layer 8. 
C)  Layer 5. 
D)  Layer 10.

Question 5

Relative ages expressed on the geologic time scale primarily resulted from the study of

Accepted Answer

A)  fossil content and spatial relationships among igneous rocks. 
B)  fossil content and spatial relationships among sedimentary rocks. 
C)  radiometric dating of igneous rocks. 
D)  radiometric dating of sedimentary rocks. 
A)  fossil content and spatial relationships among igneous rocks. 
B)  fossil content and spatial relationships among sedimentary rocks. 
C)  radiometric dating of igneous rocks. 
D)  radiometric dating of sedimentary rocks.

Question 6

How long are the half-lives of radioisotopes commonly used to date igneous and metamorphic rocks?

Accepted Answer

A)  seconds to minutes 
B)  a few years 
C)  hundreds of millions to billions of years 
D)  hundreds to thousands of years 
A)  seconds to minutes 
B)  a few years 
C)  hundreds of millions to billions of years 
D)  hundreds to thousands of years

Question 7

As understood by modern geologists,the principle of uniformitarianism implies that

Accepted Answer

A)  the Earth has always had the same basic appearance that it has today. 
B)  igneous,metamorphic,and sedimentary rocks are uniformly mixed throughout the crust. 
C)  physical processes observed today (such as erosion and volcanic eruptions)have been active in the past at approximately the same rates. 
D)  physical processes observed today (such as erosion and volcanic eruption)occurred much more rapidly in the past,quickly sculpting the Earth's surface. 
A)  the Earth has always had the same basic appearance that it has today. 
B)  igneous,metamorphic,and sedimentary rocks are uniformly mixed throughout the crust. 
C)  physical processes observed today (such as erosion and volcanic eruptions)have been active in the past at approximately the same rates. 
D)  physical processes observed today (such as erosion and volcanic eruption)occurred much more rapidly in the past,quickly sculpting the Earth's surface.

Question 8

How much of a radioactive parent isotope will remain after three half-lives have passed?

Accepted Answer

A)  one-third 
B)  three-halves 
C)  one-eighth 
D)  one-sixth 
A)  one-third 
B)  three-halves 
C)  one-eighth 
D)  one-sixth

Question 9

Which of the following geologic principles is a direct result of gravity?

Accepted Answer

A)  baked contacts 
B)  crosscutting relationships 
C)  original horizontality 
D)  inclusions 
A)  baked contacts 
B)  crosscutting relationships 
C)  original horizontality 
D)  inclusions

Question 10

Which of the following lists the time divisions on the geologic column from longest (most general)to shortest (most specific)?

Accepted Answer

A)  epoch,period,era,eon 
B)  period,epoch,eon,era 
C)  era,eon,epoch,period 
D)  eon,era,period,epoch 
A)  epoch,period,era,eon 
B)  period,epoch,eon,era 
C)  era,eon,epoch,period 
D)  eon,era,period,epoch

Question 11

Look at the figure below.The contact between the Unkar Group and the Tapeats Sandstone is a(n)

Accepted Answer

A)  conformable contact. 
B)  disconformity. 
C)  nonconformity. 
D)  angular unconformity. 
A)  conformable contact. 
B)  disconformity. 
C)  nonconformity. 
D)  angular unconformity.

Question 12

Look at the figure below.The contact between the Vishnu Schist and the Tapeats Sandstone is a(n)

Accepted Answer

A)  conformable contact. 
B)  disconformity. 
C)  nonconformity. 
D)  angular unconformity. 
A)  conformable contact. 
B)  disconformity. 
C)  nonconformity. 
D)  angular unconformity.

Question 13

What is the principle of uniformitarianism? How does this principle apply to our understanding of the Earth system? How is this useful in the context of relative dating?

Accepted Answer

Uniformitarianism states,"The present is

Question 14

Which of the following statements is true regarding the clasts (labeled 5)inside the granite pluton?

Accepted Answer

A)  The inclusions are the same age as the pluton. 
B)  The inclusions are younger than the pluton. 
C)  The inclusions are older than the pluton. 
D)  The relative age of the inclusions and the pluton cannot be determined. 
A)  The inclusions are the same age as the pluton. 
B)  The inclusions are younger than the pluton. 
C)  The inclusions are older than the pluton. 
D)  The relative age of the inclusions and the pluton cannot be determined.

Question 15

Your friend the archaeologist,who studies the ancient human past,has asked you to find a numerical date for some hominid artifacts found buried by ash from a volcanic eruption.To do this,you can use carbon-14 dating,which has a half-life of 5,730 years,or uranium-238,which has a half-life of
4.5 billion years.Based on their half-lives,which isotopic dating system will give your friend the most accurate numerical age? Explain.

Accepted Answer

Isotopic dating techniques use ratios of

Question 16

If an igneous dike cuts across a sequence of sedimentary beds,then

Accepted Answer

A)  the beds must be older. 
B)  the dike must be older. 
C)  the beds and the dike must have formed at the same time. 
D)  their relative ages cannot be determined from the information given. 
A)  the beds must be older. 
B)  the dike must be older. 
C)  the beds and the dike must have formed at the same time. 
D)  their relative ages cannot be determined from the information given.

Question 17

Look at the figure below.Notice the erosional surface on the top of the Muav Limestone.This contact between the Muav limestone and the Temple Butte Formation is an example of a(n)

Accepted Answer

A)  conformable contact. 
B)  disconformity. 
C)  nonconformity. 
D)  angular unconformity. 
A)  conformable contact. 
B)  disconformity. 
C)  nonconformity. 
D)  angular unconformity.

Question 18

What type of age does the measurement of parent and daughter isotopes in a mineral determine?

Accepted Answer

A)  relative age 
B)  numerical age 
C)  seasonal age 
D)  fossil age 
A)  relative age 
B)  numerical age 
C)  seasonal age 
D)  fossil age

Question 19

Based on the figure,what is the age of Layer 7 relative to Layer 3?

Accepted Answer

A)  Layer 7 is younger than Layer 3. 
B)  Layer 7 is older than Layer 3. 
C)  Layer 7 and Layer 3 are the same rock type,so they are the same age. 
D)  Their relative ages cannot be determined. 
A)  Layer 7 is younger than Layer 3. 
B)  Layer 7 is older than Layer 3. 
C)  Layer 7 and Layer 3 are the same rock type,so they are the same age. 
D)  Their relative ages cannot be determined.

Question 20

How is the half-life of a radioactive parent isotope defined?

Accepted Answer

A)  the time it takes for half of the parent isotope to decay 
B)  half the time it takes for the amount of parent isotope to reach zero 
C)  the time it takes the parent isotope to go through half the decay steps necessary to produce a stable daughter isotope 
D)  half of the average rate of decay of the parent isotope 
A)  the time it takes for half of the parent isotope to decay 
B)  half the time it takes for the amount of parent isotope to reach zero 
C)  the time it takes the parent isotope to go through half the decay steps necessary to produce a stable daughter isotope 
D)  half of the average rate of decay of the parent isotope

Exam 10: Deep Time: How Old Is Old

Which of the following is true of the geologic column?

The surface below sedimentary rocks that overlie igneous or metamorphic rocks is termed a(n)

Accurate radiometric dating typically requires that a rock contains a measurable amount of

The oldest geologic unit is

Relative ages expressed on the geologic time scale primarily resulted from the study of

How long are the half-lives of radioisotopes commonly used to date igneous and metamorphic rocks?

As understood by modern geologists,the principle of uniformitarianism implies that

How much of a radioactive parent isotope will remain after three half-lives have passed?

Which of the following geologic principles is a direct result of gravity?

Which of the following lists the time divisions on the geologic column from longest (most general)to shortest (most specific)?

Look at the figure below.The contact between the Unkar Group and the Tapeats Sandstone is a(n)

Look at the figure below.The contact between the Vishnu Schist and the Tapeats Sandstone is a(n)

What is the principle of uniformitarianism? How does this principle apply to our understanding of the Earth system? How is this useful in the context of relative dating?

Which of the following statements is true regarding the clasts (labeled 5)inside the granite pluton?

If an igneous dike cuts across a sequence of sedimentary beds,then

Look at the figure below.Notice the erosional surface on the top of the Muav Limestone.This contact between the Muav limestone and the Temple Butte Formation is an example of a(n)

What type of age does the measurement of parent and daughter isotopes in a mineral determine?

Based on the figure,what is the age of Layer 7 relative to Layer 3?

How is the half-life of a radioactive parent isotope defined?

The Earth in Context

The Way the Earth Works: Plate Tectonics

Patterns in Nature: Minerals

Up From the Inferno: Magma and Igneous Rocks

The Wrath of Vulcan: Volcanic Eruptions

Pages of the Earths Past: Sedimentary Rocks

Metamorphism: a Process of Change

A Violent Pulse: Earthquakes

Crags,cracks,and Crumples: Crustal Deformation and Mountain Building

A Biography of the Earth

Riches in Rock: Energy and Mineral Resources

Unsafe Ground: Landslides and Other Mass Movements

Streams and Floods: the Geology of Running Water

Restless Realm: Oceans and Coasts

A Hidden Reserve: Groundwater

Dry Regions: the Geology of Deserts

Amazing Ice: Glaciers and Ice Ages

Global Change in the Earth System

Introducing Rocks

A Surface Veneer: Sediments and Soils

The Rock Cycle

The Earth’s Interior Revisited: Insights from Geophysics

Memories of Past Life: Fossils and Evolution

Ever-Changing Landscapes and the Hydrologic Cycle

Prelude: And Just What is Geology?

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