1. Is one scientific field necessarily better than another? List what sciences have been mentioned so far in this book and rank them in order of what you perceive as most scientific to least scientific. What evidence do you have to justify such a list? Compare your list with other students in the class to see if they share your consensus.
2. Practice mapmaking in your everyday life, Draw a map for someone who needs directions and include the three features that should be on every map. Has someone ever given you poor verbal directions or a badly drawn map? If so, what would have helped to prevent the considerable time you spent being lost?
3. A stratigraphic sequence has a limestone bed at the base, which is overlain by a shale, which in turn is overlain by a sandstone; the entire sequence is cross-cut by a fault. For this sequence, what is the order (from oldest to youngest) of the geologic events represented? What if you find inclusions of the sandstone in the shale? Would you change your assessment, and if so, why?
4. You go to an area with dinosaur fossils and find fragments of Coelophysis, a theropod previously known only from the Late Triassic, in the same stratum that contains the remains of Allosaurus, a theropod only known from the Late Jurassic. What are at least two hypotheses to explain your observation? How can both be falsified?
5. How could a transgression occur without a change in sea level (which is caused by more water in the world's oceans)? How could a regression occur without sea-level changes?
6. What is the minimum number of alpha decays that occurred between the parent element of 238U and the final stable daughter element of 206Pb? How did you arrive at this number?
7. How is compound interest in savings accounts similar to radiometric age dating? Provide mathematical proofs through some examples.
8. What alternative explanations could account for the sameness of age dates derived from the five different radiometric methods given in Table 4.4? What evidence would be needed to falsify the accuracy of these age dates?
9. How can plate tectonics be responsible for the following circumstances in both relative and absolute age dating:
a. Stratigraphic sequences that have the oldest fossils at the top and the youngest fossils at the bottom.
b. Strata tilted into a vertical position.
c. Volcanic ash layers that show older radiometric ages than found in underlying strata.
d. Unconformities that show considerable angles between strata below and above the unconformity.
e. Younger radiometric ages for metamorphic rocks than found in surrounding sedimentary rocks in a mountain range.
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