Module 6: Geologic Time Lab
Record your answer to Lab Exercise, Step 3, Question 17. How long ago were the fossils found in Layer F formed?
542-488 mya
Record your answer to Lab Exercise, Step 2, Question 12. How long ago was the igneous rock in rock unit C formed?
140.8 mya
Record your answer to Lab Exercise, Step 3, Question 18. What is the least amount of time that could have passed during the hiatus represented by younger unconformity seen in Figure 9.12?
150.4 million years
Record your answer to Lab Exercise, Step 3, Question 14 . How long ago were the fossils found in Layer A formed?
201.6-145.5 mya
Record your answer to Lab Exercise, Step 2, Question 11. How long ago was the igneous rock in rock unit B formed?
352 mya
Record your answer to Lab Exercise, Step 3, Question 15. How long ago were the fossils found in Layer D formed?
444-416 mya
Record your answer to Lab Exercise, Step 3, Question 16. How long ago were the fossils found in Layer E formed?
488-444 mya
Record your answer to Lab Exercise, Step 3, Question 19. What is the least amount of time that could have passed during the hiatus represented by the older unconformity seen in Figure 9.12?
708 million years
Which is the youngest geologic structure in Figure 9.17?
A
During what period were the fossils in Layer F formed?
Cambrian Period
Which is the oldest geologic structure in Figure 9.17?
D
What is the proper order of geologic structures B, C, D, and F in Figure 9.17 from oldest to youngest?
D, C, B, F
Which letter represents an unconformity in Figure 9.17?
E
Which letter represents a fault in Figure 9.17?
F
During what period were the fossils in Layer A formed?
Jurassic Period
During what period were the fossils in Layer E formed?
Ordovician Period
What relative dating principle states that fossils in a sequence of sedimentary rock layers succeed one another in a definite, recognizable order?
Principle of Faunal Succession
What relative dating principle states that in a sequence of sedimentary rocks, unless overturned, the oldest beds are at the bottom and the youngest beds are at the top?
Principle of Superposition
Which of the following principles is NOT used in determining the relative age of rocks?
Principle of Vertical Continuity
During what period were the fossils in Layer D formed?
Silurian Period
What type of unconformity appears between two parallel sedimentary layers?
a disconformity
The Principle of Lateral Continuity states
a layer of sedimentary rock originally extended in all directions until it thinned to zero or reached the edge of the basin
What type of unconformity appears between a sedimentary layer and an igneous or metamorphic rock body?
a nonconformity
What type of unconformity appears between a tilted sedimentary strata and a horizontal overlying layer?
an angular unconformity
The Principle of Cross-cutting Relationships states that
geologic structures that cut across other structures are younger than the structures they cut across.
If a sample of radioactive material contains a parent isotope with a half-life of 3 years, then at the end of 6 years
one-quarter of the parent isotope remains.
Record your answer to Lab Exercise, Step 2, Question 13. How long ago was the metamorphic rock in rock unit G formed?
1250 mya
