Geologic Time Review

Front

What are fossils?

Back

Preserved remains or traces of an organism that lived in the past.

Front

What is absolute age?

Back

The age of a rock or fossil in years, determined through methods like radiometric dating.

Front

What is relative age?

Back

The age of a rock or fossil in comparison to other rocks or fossils, without exact dates.

Front

How do geologists use relative dating?

Back

By placing rock layers in order from oldest to youngest.

Front

What is the law of superposition?

Back

A principle stating that in undisturbed sedimentary rock layers, the oldest layers are at the bottom.

Front

What is an example of absolute dating?

Back

Radiometric dating, which measures the decay of radioactive isotopes.

Front

What is the difference between absolute and relative dating?

Back

Absolute dating provides a specific age in years, while relative dating places events in order without exact dates.

Front

What is a carbon film?

Back

A type of fossil that forms when organic material is compressed and leaves a thin film of carbon.

Front

What are vertebrates?

Back

Animals with a backbone, such as mammals, birds, reptiles, amphibians, and fish.

Front

What are invertebrates?

Back

Animals without a backbone, such as insects, arachnids, and mollusks.