Name______________________________________________ Date ___________________________ Period ______
1. Define the following terms:





Absolute dating
Radioactive Dating
Half life
Parent Isotope
Daughter Isotope
2. A paleontologist found a rock that contains the radioactive isotope potassium-40, (which has a
half life of 1.3 billion years) and the stable isotope argon-40 which the potassium-40 decays into. If
the ratio of the parent isotope to the daughter isotope is 6.25 : 93.75; how old is the rock?
Complete the table below to help you find the answer.
# of ½ lives
0
1
% of parent
100
50
% of daughter
0
50
2
3
4
12.5
5
3.125
97.875
1.3 billion yrs
½ life (billion yrs)
3. Jane and Dane came back from Scotland Yard and they have been called to
the Congo to investigate the discovery of the fossil remains of an ancient animal
which might be a mastodon. Mastodons were large, tusked, mammal species of
the extinct genus Mammut, which inhabited Asia, Africa, Europe, North America
and Central America from the Oligocene through Pleistocene, 33.9 mya to 11,000 years ago. They
will have to miss the LZ Regional Basketball final game, but duty calls. When they arrive they
determine that they can use carbon 14 dating to determine the age of the fossil. The fossil
contains 4.69 mg of carbon 14 (the parent isotope) and 146.81 mg of nitrogen 14 (the daughter
isotope). The ½ life of carbon 14 is 5,730 yrs. How old is this fossil?
Use the chart to help Jane and Dane solve this problem.
# of ½ lives
0
1
2
% of parent
100
50
25
% of daughter
0
50
Amount of
Parent (mg)
½ life (yrs)
150
mg
5730 yrs
3
87.5
4
5
6
7
4. Explain the difference between relative dating and absolute (radioactive) dating.
5. Define the following terms:

Geology

Relative Dating

Superposition

Original Horizontality

Lateral Continuity

Cross-Cutting Relationships

Inclusions

Faunal Succession

Fossils

Extinct

Geologic time scale

Paleontologist

Index fossils

Geologic column
6. What is the age of the earth?
7. James Hutton, the Scottish geologist said “the present explains the past.” In your own words
explain what he meant by this.
8. Nicholas Steno, a Danish physician developed ideas about how rocks and fossils form. These
ideas are used in a technique called relative dating. List and explain 6 ways geologist use to
determine the relative age of rock layers.
8. Name 5 ways in which fossils are formed and preserved.
9. What are index fossils and how do they help geologists date rock formations?
10. What is the name of this index fossil that lived 750 million years ago through the Cambrian
Period of the Paleozoic Era?
11. What usually marks the divisions of geologic time?
12. What was the Period of Geologic time when dinosaurs roamed the earth?
13. What is the name of the Geologic Period we are currently in? What Era are we in?
14. During what period of geologic time was the earth covered with glaciers?
15. What period did flowering plants evolve in?
16. When did modern humans appear on earth?
17. What era is the age of mammals?
18. The figure on the left is an example of
what relative dating principles? Explain.
19. Put the rock layers in Figure 2 in order from oldest to youngest. What relative dating principles
did you use?
FIGURE 2
20. Use Figure 3 to answer the following questions.
Letter G is called an ___________________________. This represents a
______________________________________ relationship. Layer G is ___________________
than layers J, K, F, and H and B.
Letter Z is pointing to ______________________________.
Which is older Z or C? Explain.
FIGURE 3
Z
21. Label the layers of the Earth in the following diagram
22. What are the two types of crust and give their characteristics.
23. Describe the following parts of the mantle.
Lithosphere –
Asthenosphere -
24. How are the outer and inner parts of the core different?
25. What do scientists use to determine what the inside of the Earth looks like?
26. What creates the magnetic field that surrounds the Earth?
27. Alfred Wegener, a famous geologist, hypothesized that the plates and continents were once all
touching. What was this super continent called and what name did Alfred Wegener give this
process of plate/continent movement?
28. Define the following types of plate boundaries and draw a picture
Boundary Definition
Convergent-
Divergent-
Transfrom-
Picture
29. Explain the idea of convection currents and how they affect the location of continents.
30. What geologic features are a result of convergent, divergent, and transform boundaries?
31. What does ocean crust do when it collides with continental crust? Why?
32. What is an example of a transform fault in the United States?
33. How do island chains such as Hawaii get formed?
34. What is an earthquake and list the possible damage that can result from one.
35. Define the following terms:
TsunamiFocusEpicenterIntensityMagnitudeSeismographSeismogram36. Label the following diagram with the terms fault, focus, and epicenter.
37. What is the relationship between the depth of a focus and the damage that is done by the EQ?
38. What is the relationship between lag time and the distance the epicenter is away from where
the EQ is felt?
39. What does it mean if an EQ registers as 12 on the Mercalli Scale?
40. What does it mean if an EQ registers as 1 on the Richter Scale?
41. What are the differences between P, S, and L waves that earthquakes produce?
42. How do scientists find the location of an earthquake’s epicenter?
43. How do you geologists calculate the speed of waves from EQ’s?