Question 1

Which of the following is an erosion surface that separates two sets of sedimentary layers with nonparallel bedding planes?

Accepted Answer

A) angular unconformity 
B) cross-bed 
C) disconformity 
D) nonconformity 
A) angular unconformity 
B) cross-bed 
C) disconformity 
D) nonconformity

Question 2

The principle of superposition states that

Accepted Answer

A) a fault is younger than the rocks it cuts. 
B) sediments are deposited as essentially horizontal layers. 
C) the present is the key to the past. 
D) undisturbed sedimentary layers get progressively younger from bottom to top. 
A) a fault is younger than the rocks it cuts. 
B) sediments are deposited as essentially horizontal layers. 
C) the present is the key to the past. 
D) undisturbed sedimentary layers get progressively younger from bottom to top.

Question 3

Which of the following instruments is used to precisely measure isotopes for radiometric dating?

Accepted Answer

A) electron microprobe 
B) mass spectrometer 
C) geiger counter 
D) petrologic microscope 
A) electron microprobe 
B) mass spectrometer 
C) geiger counter 
D) petrologic microscope

Question 4

Which of the following radioactive isotopes has the shortest half-life?

Accepted Answer

A) carbon-14 
B) potassium-40 
C) rubidium-87 
D) uranium-238 
A) carbon-14 
B) potassium-40 
C) rubidium-87 
D) uranium-238

Question 5

The first geologic map covering an entire country was for

Accepted Answer

A) France. 
B) the United States. 
C) Russia. 
D) England. 
A) France. 
B) the United States. 
C) Russia. 
D) England.

Question 6

In order to reconstruct the geologic of rocks in a given region,geologists typically work

Accepted Answer

A) with a single era. 
B) from oldest to newest. 
C) backward in time. 
D) forward in time. 
A) with a single era. 
B) from oldest to newest. 
C) backward in time. 
D) forward in time.

Question 7

Who came up with the principle of faunal succession?

Accepted Answer

A) Charles Lyell 
B) William Smith 
C) Nicolaus Steno 
D) James Hutton 
A) Charles Lyell 
B) William Smith 
C) Nicolaus Steno 
D) James Hutton

Question 8

Which life forms were first recognized in the fossil record?

Accepted Answer

A) dinosaurs 
B) trilobites 
C) sharks 
D) humanoids 
A) dinosaurs 
B) trilobites 
C) sharks 
D) humanoids

Question 9

The study of the layers in sedimentary rock is known as

Accepted Answer

A) stratigraphy. 
B) paleontology. 
C) sedimentation. 
D) geochronology. 
A) stratigraphy. 
B) paleontology. 
C) sedimentation. 
D) geochronology.

Question 10

Geologic correlation of sedimentary rocks bounded above and below by unconformities is called

Accepted Answer

A) sequence stratigraphy. 
B) paleomagnetic stratigraphy. 
C) chemical stratigraphy. 
D) sedimentary stratigraphy. 
A) sequence stratigraphy. 
B) paleomagnetic stratigraphy. 
C) chemical stratigraphy. 
D) sedimentary stratigraphy.

Question 11

Fossils are most common in which rock types?

Accepted Answer

A) igneous 
B) metamorphic 
C) sedimentary 
D) Fossils are equally common in sedimentary,igneous,and metamorphic rocks. 
A) igneous 
B) metamorphic 
C) sedimentary 
D) Fossils are equally common in sedimentary,igneous,and metamorphic rocks.

Question 12

The absolute age of a geologic event in the rock record is

Accepted Answer

A) the number of years that has elapsed between the event and the present day. 
B) the amount of time that has elapsed between the event and the beginning of Earth's history. 
C) the number of years that has elapsed between the event and the beginning of human civilization. 
D) the amount of time that has elapsed between the event and another similar geologic event. 
A) the number of years that has elapsed between the event and the present day. 
B) the amount of time that has elapsed between the event and the beginning of Earth's history. 
C) the number of years that has elapsed between the event and the beginning of human civilization. 
D) the amount of time that has elapsed between the event and another similar geologic event.

Question 13

Major boundaries in the geologic time scale are often put there based on significant _____ events?

Accepted Answer

A) tectonic 
B) volcanic 
C) mass extinction 
D) supercontinental breakup 
A) tectonic 
B) volcanic 
C) mass extinction 
D) supercontinental breakup

Question 14

Which of the following radioactive isotopes could be used to date very old (3 billion year old)rocks?

Accepted Answer

A) uranium-238 
B) potassium-40 
C) uranium-235 
D) all of the above 
A) uranium-238 
B) potassium-40 
C) uranium-235 
D) all of the above

Question 15

Carbon-14 has a half-life of approximately _______ years and is therefore suitable to dating objects younger than approximately_________years.

Accepted Answer

A) 4 million; 5 billion 
B) 6 thousand; 70 thousand 
C) 70 thousand; 6 thousand 
D) 5 thousand; 50 thousand 
A) 4 million; 5 billion 
B) 6 thousand; 70 thousand 
C) 70 thousand; 6 thousand 
D) 5 thousand; 50 thousand

Question 16

Almost nine-tenths of Earth's history occurs during the

Accepted Answer

A) Phanerozoic. 
B) Archean. 
C) Paleozoic. 
D) Precambrian. 
A) Phanerozoic. 
B) Archean. 
C) Paleozoic. 
D) Precambrian.

Question 17

Both radiocarbon and potassium-argon dating share one specific problem that makes these methods difficult to use.What is that problem?

Accepted Answer

A) Both have short half-lives. 
B) Both have parents that are too rare to measure accurately. 
C) The half-lives of both are poorly known. 
D) Both produce daughters that are in a gaseous state. 
A) Both have short half-lives. 
B) Both have parents that are too rare to measure accurately. 
C) The half-lives of both are poorly known. 
D) Both produce daughters that are in a gaseous state.

Question 18

A rock formed with 1000 atoms of a radioactive parent element,but contains only 250 radioactive parent atoms today.If the half-life for the radioactive element is one million years,how old is the rock?

Accepted Answer

A) 250,000 years old 
B) 750,000 years old 
C) 2 million years old 
D) 4 million years old 
A) 250,000 years old 
B) 750,000 years old 
C) 2 million years old 
D) 4 million years old

Question 19

Which of the following statements is false?

Accepted Answer

A) Dikes are older than the rocks they cross-cut. 
B) Faults are younger than the rocks they cross-cut. 
C) Sills are younger than the rocks they cross-cut. 
D) Unconformities are younger than the layers they erode. 
A) Dikes are older than the rocks they cross-cut. 
B) Faults are younger than the rocks they cross-cut. 
C) Sills are younger than the rocks they cross-cut. 
D) Unconformities are younger than the layers they erode.

Question 20

A disconformity is _

Accepted Answer

A) an erosional surface between horizontal layers of sedimentary rocks. 
B) an erosional surface between igneous and sedimentary rocks. 
C) a rock unit that does not contain fossils. 
D) a rock unit that is different from the units above or below it. 
A) an erosional surface between horizontal layers of sedimentary rocks. 
B) an erosional surface between igneous and sedimentary rocks. 
C) a rock unit that does not contain fossils. 
D) a rock unit that is different from the units above or below it.

Exam 8: Clocks in Rocks: Timing the Geologic Period

Which of the following is an erosion surface that separates two sets of sedimentary layers with nonparallel bedding planes?

The principle of superposition states that

Which of the following instruments is used to precisely measure isotopes for radiometric dating?

Which of the following radioactive isotopes has the shortest half-life?

The first geologic map covering an entire country was for

In order to reconstruct the geologic of rocks in a given region,geologists typically work

Who came up with the principle of faunal succession?

Which life forms were first recognized in the fossil record?

The study of the layers in sedimentary rock is known as

Geologic correlation of sedimentary rocks bounded above and below by unconformities is called

Fossils are most common in which rock types?

The absolute age of a geologic event in the rock record is

Major boundaries in the geologic time scale are often put there based on significant _____ events?

Which of the following radioactive isotopes could be used to date very old (3 billion year old)rocks?

Carbon-14 has a half-life of approximately _______ years and is therefore suitable to dating objects younger than approximately_________years.

Almost nine-tenths of Earth's history occurs during the

Both radiocarbon and potassium-argon dating share one specific problem that makes these methods difficult to use.What is that problem?

A rock formed with 1000 atoms of a radioactive parent element,but contains only 250 radioactive parent atoms today.If the half-life for the radioactive element is one million years,how old is the rock?

Which of the following statements is false?

A disconformity is _

The Earth System

Plate Tectonics: The Unifying Theory

Earth Materials: Minerals and Rocks

Igneous Rocks: Solids From Melts

Sedimentation: Rocks Formed by Surface Processes

Metamorphism: Alteration of Rocks by Temperature and Pressure

Deformation: Modification of Rocks by Folding and Fracturing

Early History of the Terrestrial Planets

History of the Continents

Geobiology: Life Interacts With Earth

Volcanoes

Earthquakes

Exploring Earths Interior

The Climate System

Weathering,erosion,and Mass Wasting: Interactions Between the Climate and Plate Tectonic Systems

The Hydrologic Cycle and Groundwater

Stream Transport: From Mountains to Oceans

Winds and Deserts

Coastlines and Ocean Basins

Glaciers: the Work of Ice

Landscapes: Tectonic and Climate Interaction

The Human Impact of Earths Environment

Filters

Carbon-14 has a half-life of approximately _ years and is therefore suitable to dating objects younger than approximately___years.