Index Fossils

Front

What are index fossils?

Back

Index fossils are fossils of organisms that were widespread but only existed for a short period of geological time, making them useful for dating and correlating the age of rock layers.

Front

What are the two main traits of the best index fossils?

Back

The best index fossils are widespread geographically and have a short lifespan.

Front

Why is fossil #4 not a good index fossil?

Back

Fossil #4 is not a good index fossil because it is not short-lived and is found in numerous layers.

Front

Which law is NOT helpful in determining if something is an index fossil?

Back

The law stating that there should be many of the same fossils in many different layers of the same outcrop is not helpful.

Front

Which fossil is most useful for determining the relative age of rocks?

Back

The Ammonite is most useful for determining the relative age of rocks.

Front

What is the significance of widespread distribution in index fossils?

Back

Widespread distribution allows geologists to correlate rock layers across different geographic locations.

Front

What does a short lifespan of an organism indicate about its fossil?

Back

A short lifespan indicates that the organism lived during a specific time period, making its fossil useful for dating rock layers.

Front

What is an example of an index fossil?

Back

An example of an index fossil is the Trilobite.

Front

How do index fossils help in geological studies?

Back

Index fossils help in geological studies by providing a way to date and correlate rock layers based on the presence of specific fossils.

Front

What characteristics make a fossil a good index fossil?

Back

A good index fossil should be easily recognizable, widespread, and have a short geological lifespan.