Question 1

If a sandstone lies on top of a shale,

Accepted Answer

A)  the shale must be older,according to the principle of superposition. 
B)  the sandstone must be older,according to the principle of superposition. 
C)  the shale must be older,according to the principle of original horizontality. 
D)  their relative ages cannot be determined from the information given. 
A)  the shale must be older,according to the principle of superposition. 
B)  the sandstone must be older,according to the principle of superposition. 
C)  the shale must be older,according to the principle of original horizontality. 
D)  their relative ages cannot be determined from the information given. A

Question 2

A radiometric age for a mineral crystal within an igneous rock measures the amount of time that has passed since the

Accepted Answer

A)  atoms within the crystal were part of a body of molten magma. 
B)  crystal solidified. 
C)  temperature of the crystal became equal to surface temperatures. 
D)  temperature of the crystal became equal to the closure temperature for the mineral. 
A)  atoms within the crystal were part of a body of molten magma. 
B)  crystal solidified. 
C)  temperature of the crystal became equal to surface temperatures. 
D)  temperature of the crystal became equal to the closure temperature for the mineral. D

Question 3

Why have no rocks older than 4.12 Ga been found in the Earth's crust?

Accepted Answer

Rocks older than 4.12 Ga were likely re-melted during the heavy bombardment or were recycled by passing through the rock cycle.

Question 4

Dendrochronology involves dating of historic and geologic events through the study of

Accepted Answer

A)  growth layers in shells. 
B)  oxygen isotope profiles in glacial ice. 
C)  remnant magnetism in iron-rich minerals. 
D)  annual growth rings in trees. 
A)  growth layers in shells. 
B)  oxygen isotope profiles in glacial ice. 
C)  remnant magnetism in iron-rich minerals. 
D)  annual growth rings in trees.

Question 5

Referring to the graph below,after one half-life has passed,what is the ratio of parent isotopes to daughter isotopes?

Accepted Answer

A)  16:0 
B)  8:8 
C)  4:12 
D)  2:16 
A)  16:0 
B)  8:8 
C)  4:12 
D)  2:16

Question 6

If horizontal sedimentary strata overlie tilted strata (and no fault is present),the surface between the horizontal and tilted strata must be a(n)

Accepted Answer

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

Question 7

Correlate the layers in the following three stratigraphic columns by drawing lines from the top and bottom of matching formations.What is the oldest unit in this region? The youngest unit?

Accepted Answer

See the answer below.The oldes

Question 8

Which method of correlation is most reliable for determining age equivalence among bodies of rock that are physically separated by vast distances?

Accepted Answer

A)  lithologic correlation 
B)  fossil correlation 
C)  inclusion correlation 
D)  unconformity correlation 
A)  lithologic correlation 
B)  fossil correlation 
C)  inclusion correlation 
D)  unconformity correlation

Question 9

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 10

The principle of ________ explains the occurrence of older rock within a newer rock.

Accepted Answer

A)  baked contacts 
B)  cross-cutting relationships 
C)  original horizontality 
D)  inclusions 
A)  baked contacts 
B)  cross-cutting relationships 
C)  original horizontality 
D)  inclusions

Question 11

Buried erosional surfaces between parallel sedimentary strata are termed

Accepted Answer

A)  disconformities. 
B)  angular unconformities. 
C)  nonconformities. 
D)  marker beds. 
A)  disconformities. 
B)  angular unconformities. 
C)  nonconformities. 
D)  marker beds.

Question 12

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 13

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 14

Compare and contrast lithologic correlation and fossil correlation.In what circumstance is each most useful? Provide an example of each.

Accepted Answer

Student answers may include examples sim

Question 15

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 16

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 17

How is a relative age different from a numerical age? How are each of these determined?

Accepted Answer

A relative age compares the age of one g

Question 18

In the 1800s,Lord Kelvin estimated the age of the Earth,utilizing a number of assumptions.Which wrong assumption was the primary reason why his estimate (approximately 20 million years)was so wildly inaccurate?

Accepted Answer

A)  that the Earth was once hotter than it presently is today 
B)  that the Earth may have been molten when first formed 
C)  that no new heat has been added to the Earth since its initial formation 
D)  that the Earth would lose heat over time through radiation into outer space 
A)  that the Earth was once hotter than it presently is today 
B)  that the Earth may have been molten when first formed 
C)  that no new heat has been added to the Earth since its initial formation 
D)  that the Earth would lose heat over time through radiation into outer space

Question 19

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 20

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.

Exam 12: Deep Time: How Old Is Old

If a sandstone lies on top of a shale,

A radiometric age for a mineral crystal within an igneous rock measures the amount of time that has passed since the

Why have no rocks older than 4.12 Ga been found in the Earth's crust?

Dendrochronology involves dating of historic and geologic events through the study of

Referring to the graph below,after one half-life has passed,what is the ratio of parent isotopes to daughter isotopes?

If horizontal sedimentary strata overlie tilted strata (and no fault is present),the surface between the horizontal and tilted strata must be a(n)

Correlate the layers in the following three stratigraphic columns by drawing lines from the top and bottom of matching formations.What is the oldest unit in this region? The youngest unit?

Which method of correlation is most reliable for determining age equivalence among bodies of rock that are physically separated by vast distances?

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

The principle of ________ explains the occurrence of older rock within a newer rock.

Buried erosional surfaces between parallel sedimentary strata are termed

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)

Compare and contrast lithologic correlation and fossil correlation.In what circumstance is each most useful? Provide an example of each.

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

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

How is a relative age different from a numerical age? How are each of these determined?

In the 1800s,Lord Kelvin estimated the age of the Earth,utilizing a number of assumptions.Which wrong assumption was the primary reason why his estimate (approximately 20 million years)was so wildly inaccurate?

Which of the following is true of the geologic column?

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

Cosmology and the Birth of the Earth

Journey to the Center of the Earth

Drifting Continents and Spreading Seas

The Way the Earth Works: Plate Tectonics

Patterns in Nature: Minerals

Up From the Inferno: Magma and Igneous Rocks

Pages of Earths Past: Sedimentary Rocks

Metamorphism: a Process of Change

The Wrath of Vulcan: Volcanic Eruptions

A Violent Pulse: Earthquakes

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

A Biography of the Earth

Squeezing Power From a Stone: Energy Resources

Riches in Rock: 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

An Envelope of Gas: the Earths Atmosphere and Climate

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 in the Earth System

the Earths Interior, Revisited: Seismic Layering, Gravity, and the Magnetic Field

Memories of Past Life: Fossils and Evolution

Ever-Changing Landscapes and the Hydrologic Cycle

Prelude: and Just What Is Geology

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