01
True or false
1 point
True or false: An event dated 200 million years ago is older than an event dated 100 million years ago.
Free Practice Quiz Question List
05 Geologic Time and Dating Online Quiz Questions
Use this free practice quiz with 20 questions to review 05 Geologic Time and Dating, test your knowledge, and prepare for your next test or exam.
20 questions
02
Fill in the blank
1 point
In radioactive decay, the isotope that decays into another isotope is called the isotope.
03
Choose one
1 point
In an undisturbed sequence of deposited rock layers, where is the oldest layer?
- A
The oldest layer is at the top.
- B
The oldest layer is at the bottom.
- C
All layers are the same age.
- D
The youngest layer is at the bottom.
04
Written response
1 point
What is the name of the method that places rocks and events in sequence without assigning an age in years?
05
Choose one
1 point
Which sequence correctly places the Cretaceous, Mesozoic, and Phanerozoic in the geologic time scale?
- A
Cretaceous Era within the Mesozoic Period within the Phanerozoic Eon
- B
Mesozoic Eon within the Cretaceous Era within the Phanerozoic Period
- C
Cretaceous Period within the Mesozoic Era within the Phanerozoic Eon
- D
Phanerozoic Era within the Mesozoic Eon within the Cretaceous Period
06
True or false
1 point
True or false: A numerical date from a mineral grain in a sedimentary rock necessarily gives the age when the sediment was deposited.
- A
True
- B
False
07
Fill in the blank
1 point
A surface representing erosion or a period when sediment was not deposited is called an .
08
Choose one
1 point
Two rock layers in different locations contain the same widespread, short-lived index fossil. What is the most defensible inference?
- A
The layers likely formed at roughly the same time and can be correlated.
- B
The layers must have formed in the same location.
- C
The layers must have the same thickness.
- D
The layers must have identical colors.
09
Choose all
1 point
Which considerations help geologists assess whether a radiometric age is reliable? Select all that apply.
- A
Assess whether the sample remained a sufficiently closed system.
- B
Consider whether heating, fluids, or weathering may have altered the isotope record.
- C
Check that the isotope system suits the material and the age range.
- D
Assume any measured mineral age dates every part of the rock's history.
10
Choose all
1 point
Which approaches can help geologists correlate strata from different locations? Select all that apply.
- A
Tracing layers between locations
- B
Comparing rock features and fossils
- C
Assuming all layers at the same elevation formed at the same time
- D
Using numerical dates to anchor relative sequences
11
Written response
1 point
The chart gives the base of the Cretaceous as about 143 Ma and the base of the Paleogene as 66 Ma. What is the numerical difference between these stated ages? Enter the value in Ma.
12
Choose one
1 point
What role does a Global Boundary Stratotype Section and Point (GSSP) serve?
- A
A laboratory instrument used to measure isotope ratios
- B
A designated reference point in a rock section used to define a boundary
- C
A calculation that converts Ma into Ga
- D
A fossil species that must occur at every geologic boundary
13
True or false
1 point
True or false: A numerical age measured from a mineral may date its crystallization rather than every part of the surrounding rock's history.
- A
True
- B
False
14
Open ended
1 point
A sedimentary layer lies between volcanic ash layers above and below it. Explain how numerical dates from both ash layers can constrain the sedimentary layer's depositional age, and why those dates are bounds rather than a direct date on its sediment grains.
15
Written response
1 point
What is the term for a surface in the rock record that represents erosion or a period when sediment was not deposited?
16
Choose one
1 point
Four sedimentary layers, A through D, are arranged from top to bottom in an undisturbed sequence. Which layer is oldest?
- A
Layer A
- B
Layer B
- C
Layer C
- D
Layer D
17
Choose one
1 point
A conglomerate contains pebbles enclosed in its rock matrix. What can be inferred about their relative ages?
- A
The conglomerate is older than the pebbles.
- B
The pebbles are older than the conglomerate.
- C
The pebbles and conglomerate must be the same age.
- D
Their relative ages cannot be determined.
18
Choose one
1 point
Two distant rock layers have different rock types but contain the same widespread, short-lived index fossil. What is the most useful inference?
- A
The layers must have identical rock types.
- B
The layers must have formed in the same location.
- C
The layers likely formed at roughly the same time.
- D
The layers must contain the same minerals.
19
Choose one
1 point
A fault offsets several rock layers. What does the cross-cutting relationship indicate?
- A
The fault is younger than the layers it offsets.
- B
The fault is older than the layers it offsets.
- C
The fault and layers must be the same age.
- D
The relative ages cannot be determined.
20
Written response
1 point
According to the International Commission on Stratigraphy's 2024/12 chart, what is the numerical age of the base of the Paleogene? Enter the value in Ma.