Mr. Wilson’s 8th Grade Science Class
Weekly Homework Assignment (11/30-12/4) (DUE Friday 12/4)
Score: ___________/20 = ____________%
Instructions: For each question you answer, you must provide reasoning as to why that is the correct
answer in 2-3 sentences. NO CREDIT WILL BE GIVEN FOR ANSWERS WITHOUT REASONING!
1. Which is a process that allows scientists to compare rock layers with others in a sequence to determine
their age?
A. radiometric dating
B. absolute dating
C. relative dating
Reasoning:
2. Which is the best example of an index fossil?
A. corals found in rock layers worldwide
B. dinosaur bones found only in Australia
C. footprints of different types of dinosaurs
D. casts of bird feathers found in all layers of rock in an area
Reasoning:
3. What can be concluded about the age of fossils in undisturbed rock layers?
A. The top layer has the oldest fossils.
B. The bottom layer has the oldest fossils.
C. The top layer has the oldest and youngest fossils.
Reasoning:
4. Which would least likely be an earth process that has influenced the formation of rock layers and fossil
formation?
A. high levels of soil erosion
B. air masses forming storms
C. movement of crustal plates
Reasoning:
5. Why are index fossils used as guides to determine the age of rocks?
A. Each index fossil lived during a specific geologic time period.
B. All index fossils lived during all the periods of geologic time.
C. Index fossils are very rare and are not commonly found in rocks.
Reasoning:
6. Why are index fossils good clues for identifying when rocks were formed?
A. They are easy to form in rock.
B. They are difficult to form in rock.
C. They only existed during specific periods of time.
Reasoning:
7. What is the relative age of an igneous rock intrusion between domed layers of sedimentary rock?
A. It is older than the sedimentary rock.
B. It is younger than the sedimentary rock.
C. It is the same age as the sedimentary rock.
Reasoning:
8. Which is used to find the relative age of a rock?
A. composition of rock layers
B. position of rock layers
C. carbon-14 dating
D. uranium dating
Reasoning:
9. Why are sedimentary rocks more useful than other rocks for finding evidence of the Earth’s history?
A. High heat melts the rock, trapping fossils inside.
B. Minerals left behind by moving water seal and protect fossil remains.
C. The composition of sedimentary rocks prevents them from being weathered and eroded.
D. The composition of sedimentary rocks protects the fossils and prevents them from being
melted by magma.
Reasoning:
10. Sedimentary rock layers are typically deposited horizontally, with each successive layer deposited on
top of the previous layer. Which best describes how a fault will affect the appearance of horizontal
sedimentary rock layers?
A. The sedimentary rock layers will appear thicker due to a fault.
B. The sedimentary rock layers will appear thinner due to a fault.
C. The sedimentary rock layers will shift to vertical alignment due to a fault.
D. The sedimentary rock layers will appear broken and shifted due to a fault.
Reasoning: