Question 1

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 to daughter isotope 
B) half the time it takes for the parent isotope to completely decay to daughter isotopes 
C) the time for parent isotopes to undergo half the decay steps to produce a 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 to daughter isotope 
B) half the time it takes for the parent isotope to completely decay to daughter isotopes 
C) the time for parent isotopes to undergo half the decay steps to produce a daughter isotope 
D) half of the average rate of decay of the parent isotope

Question 2

In the 1800s Lord Kelvin estimated the age of 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 Earth was once hotter than it presently is today 
B) that Earth may have been molten when first formed 
C) that no new heat has been added to Earth since its initial formation 
D) that Earth would lose heat over time through radiation into outer space 
A) that Earth was once hotter than it presently is today 
B) that Earth may have been molten when first formed 
C) that no new heat has been added to Earth since its initial formation 
D) that Earth would lose heat over time through radiation into outer space

Question 3

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 4

Discuss what the numerical age represents when radiometrically dating a basalt,a gneiss,and a quartz sandstone.

Accepted Answer

The numerical age of a basalt gives the

Question 5

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 components 
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 components 
D) their relative ages cannot be determined from the information given

Question 6

In the image below,contact #3 is both a ________ and a(n)________ at various points.

Accepted Answer

A) conformable contact;unconformity 
B) fault;unconformity 
C) nonconformity;angular unconformity 
D) disconformity;nonconformity 
A) conformable contact;unconformity 
B) fault;unconformity 
C) nonconformity;angular unconformity 
D) disconformity;nonconformity

Question 7

Seasonal changes create layering in glaciers known as ________.

Accepted Answer

A) growth banding 
B) rhythmic layering 
C) growth layering 
D) annual banding 
A) growth banding 
B) rhythmic layering 
C) growth layering 
D) annual banding

Question 8

The ________ represents the global strata from the entire Earth's history.

Accepted Answer

A) stratigraphic formation 
B) lithologic sequence 
C) geologic column 
D) stratigraphic column 
A) stratigraphic formation 
B) lithologic sequence 
C) geologic column 
D) stratigraphic column

Question 9

Uniformitarianism is succinctly summarized by which phrase?

Accepted Answer

A) The future is the key to the present. 
B) The present is the key to the past. 
C) The past is the key to the present. 
D) The present is the key to the future. 
A) The future is the key to the present. 
B) The present is the key to the past. 
C) The past is the key to the present. 
D) The present is the key to the future.

Question 10

According to the image 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 11

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 12

If the ratio of parent to daughter isotopes is 25:75,how many half-lives have passed?

Accepted Answer

A) 2 
B) 3 
C) 1 
D) 4 
A) 2 
B) 3 
C) 1 
D) 4

Question 13

The geologic time scale is broken into a series of eras,epochs,and periods based mainly on the fossils found in each section.This is an example of ________ dating.

Accepted Answer

A) relative age 
B) radiometric 
C) numerical 
D) isotopic 
A) relative age 
B) radiometric 
C) numerical 
D) isotopic

Question 14

Place the layers and geologic events in order from oldest to youngest.Make sure to include all of the layers and events,including the top surface.

Accepted Answer

The answer of Place the layers and geologic events in...

Question 15

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 16

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 17

Radiometric dates applied to sedimentary rocks produce ages that ________.

Accepted Answer

A) are just as accurate as when the technique is applied to igneous rocks 
B) are too young (postdate sedimentary deposition) 
C) are too old (predate sedimentary deposition) 
D) represent the time the sediments became lithified 
A) are just as accurate as when the technique is applied to igneous rocks 
B) are too young (postdate sedimentary deposition) 
C) are too old (predate sedimentary deposition) 
D) represent the time the sediments became lithified

Question 18

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

Accepted Answer

Rocks older than 4.12 Ga were

Question 19

Which of the following statements regarding the geologic column is FALSE?

Accepted Answer

A) The geologic column will never be complete because there will always be information that has been lost due to erosion. 
B) The geologic column will never be complete because new formations and fossils are found almost daily that shift the time boundaries. 
C) The geologic column can be seen in its entirety in Ethiopia,where the earliest hominid fossils are found. 
D) By adding numerical ages to the geologic column,geologists continuously change the geologic time scale. 
A) The geologic column will never be complete because there will always be information that has been lost due to erosion. 
B) The geologic column will never be complete because new formations and fossils are found almost daily that shift the time boundaries. 
C) The geologic column can be seen in its entirety in Ethiopia,where the earliest hominid fossils are found. 
D) By adding numerical ages to the geologic column,geologists continuously change the geologic time scale.

Question 20

________ ages are used to set the beginning and end points of eras,epochs,and periods on the geologic time scale.

Accepted Answer

A) Relative 
B) Systematic 
C) Radiometric 
D) Isotrophic 
A) Relative 
B) Systematic 
C) Radiometric 
D) Isotrophic

Exam 10: Deep Time: How Old Is Old

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

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

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

Discuss what the numerical age represents when radiometrically dating a basalt,a gneiss,and a quartz sandstone.

If a sandstone lies on top of a shale,________.

In the image below,contact #3 is both a ________ and a(n)________ at various points.

Seasonal changes create layering in glaciers known as ________.

The ________ represents the global strata from the entire Earth's history.

Uniformitarianism is succinctly summarized by which phrase?

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

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

If the ratio of parent to daughter isotopes is 25:75,how many half-lives have passed?

The geologic time scale is broken into a series of eras,epochs,and periods based mainly on the fossils found in each section.This is an example of ________ dating.

Place the layers and geologic events in order from oldest to youngest.Make sure to include all of the layers and events,including the top surface.

Buried erosional surfaces between parallel sedimentary strata are termed ________.

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

Radiometric dates applied to sedimentary rocks produce ages that ________.

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

Which of the following statements regarding the geologic column is FALSE?

________ ages are used to set the beginning and end points of eras,epochs,and periods on the geologic time scale.

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 Earth S Past: Sedimentary Rocks

Metamorphism: A Process of Change

A Violent Pulse: Earthquakes

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

A Biography of 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

Interlude A: Rock Groups

Interlude B: A Surface Veneer: Sediments and Soils

Interlude C: The Rock Cycle

Interlude D: The Earth S Interior Revisited: Insights From Geophysics

Interlude E: Memories of Past Life: Fossils and Evolution

Interlude F: An Introduction to Landscapes and the Hydrologic Cycle

Filters

In the image below,contact #3 is both a and a(n) at various points.