1. Geologists have subdivided geologic time into units
based on
1) rock type 3) erosion rates
2) fossil evidence 4) landscape development
2. Approximately how long ago did the solar system
originate?
1) 570,000,000 years 3) 4,500,000,000 years
2) 1,000,000,000 years 4) 10,000,000,000 years
3. When did the Jurassic Period end?
1) 66 million years ago 3) 163 million years ago
2) 146 million years ago 4) 190 million years ago
4. Which radioactive element would a scientist most likely
have used to date the age of a fossil that is 10,000 years
old?
1) potassium-40 3) uranium-238
2) carbon-14 4) rubidium-87
5. One half of the radioactive potassium-40 (K
40
) in an
igneous rock has decayed to argon-40 (Ar
40
). About how
many years ago was this rock formed?
1) 1.4 × 10
9
3) 4.2 × 10
9
2) 2.8 × 10
9
4) 9.8 × 10
9
6. The fossil record indicates that most of the plants and
animals that lived on Earth in the past
1) appeared during the Cambrian Period
2) became index fossils
3) have become extinct
4) lived on land
7. Base your answer to the following question on The cross section below, which shows several rock formations found in New York
State. The rock layers have not been overturned.
How does this cross section indicate that the Stockton sandstone is the oldest rock layer?
8. Base your answer to the following question on the cross section below. Letters A through H represent rock units in which
overturning has not occurred.
Two inferences about the cross section are listed below.
Inference 1: Rock unit G is older than the fault.
Inference 2: Rock unit A is younger than rock unit C.
Explain how each inference is supported by evidence in the cross section.