Fossils Test Review

Trilobite fossils are found in Cambrian rocks but not in Triassic rocks.  Which statement best explains why trilobite fossils are missing from Triassic rocks?

• trilobites went extinct before the Triassic
• fossils did not form during the Triassic
• volcanoes and earthquakes destroyed only trilobite fossils during the Triassic
• trilobite fossils just haven’t been found yet

All are types of fossils EXCEPT:

• mineral replacement
• bone neutralization
• carbon film
• cast and molds

The half-life of Carbon-14 is 5,730 years.  How much parent material would be left after 5,730 years?

• 100%
• 75%
• 50%
• 25%

The absolute age of a rock is the approximate number of years ago that the rock formed. The absolute age of an igneous rock can best be determined by

• comparing the radioactive isotopes
• comparing the crystal sizes
• comparing the relative position
• comparing the environment

Unless a layer of rocks has been overturned or shifted, the bottom rock layer

• has fossils
• is the oldest
• has the greatest amount of minerals
• has the hardest rocks

What characteristics would make an index fossil useful for determining the relative age of a variety of rock layers?

• a wide time range and a narrow geographic range
• a wide time range and a wide geographic range
• a narrow time range and a wide geographic range
• a narrow time range and a narrow geographic range

In what way are index fossils and layers of ash found in ice cores similar?

• both were formed only during the Maastrichtian period
• both strongly resist chemical weathering
• both can be used for relative dating
• both only occur in igneous rocks

Ice cores are most useful for determining:

• the amount of earthquakes in the past
• the atmospheric composition in the past
• the number of species alive in the past
• speed of geologic plates in the past

Many fossils of marine organisms are found in what is now desert.  Which hypothesis best explains this?

• marine organisms lived on land in the past
• the desert was once an ocean
• the desert moved from the equator south
• the fossils were moved by people

The age of Earth is measured in _________ of years

• hundreds
• thousands
• millions
• billions