Name: ______________________________________________________
Period: ___
Fossil Formation and Rock Dating Reading
Questions listed as “Check” require at least a two-sentence answer.
Fossils: pg 528
1) What is the definition of a fossil?
2) What is catastrophism?
3) Why was catastrophism eventually rejected?
4) What is uniformitarianism?
5) Check: how would you compare and contrast catastrophism and uniformitarianism?
6) Check: the largest mass extinction in history occurred at the end of the Permian period. Over 90% of all species
living at the time went extinct.
a. What might a catastrophism specialist suggest was the reason?
b. What might an uniformitarianism specialist suggest was the reason?
7) Do most dead organisms become fossils?
8) Briefly describe each of the following types of preservation:
a. Preserved remains:
b. Carbon films:
c. Mineral replacement:
d. Molds:
e. Casts:
f.
Trace fossils:
9) Check: Trace fossils are the most common types of fossils. Scientists have theorized that this is because
organisms have only one body but many activities. How does this account for there being more trace fossils
than other types of fossils?
10) What is a paleontologist?
11) Check: how do fossils allow us to infer what ancient environments were like?
12) Has the global climate been relatively stable or has it changed throughout time?
13) Answer question #4 on page 536.
14) Answer question #7 on page 536.
15) Why is Ukhaa Tolgod a good source of fossils? In other words, why were so many organisms preserved?
Relative-Age Dating: pg 538
16) What is the definition of relative age?
17) What is the definition of superposition?
18) In what orientation do rocks originally form?
19) What is the definition of an inclusion? How might they form?
20) Check: you come across an exposed rock face with three layers. Layer A is on the bottom, B in the middle, and C
on top.
a. Layer B is 50 million years old. What can you know about the age of Layer A and Layer C?
b. If an inclusion cuts across all three layers what can you know about the age of the intrusion?
21) What is the definition of an unconformity?
22) Check: Explain how it is possible for there to be a gap in the rock record.
23) What is the definition of correlation?
24) What do correlations allow us to do?
25) According to the diagram on page 543, what area contains the oldest rocks: the Grand Canyon, Zion, or Bryce?
26) What are index fossils?
27) Check: how would using a species that existed for a long period of time as an index fossil interfere with attempts
to date layers of rock?
28) Check: answer question #9 on page 544.