2.3 Geologic Time Vocabulary

Front

What is radioactive dating?

Back

A method used to determine the age of rocks by measuring the decay of isotopes.

Front

What does the Law of Superposition state?

Back

In undisturbed rock layers, older layers are found below younger layers.

Front

What is the definition of absolute age?

Back

The age of a rock given as the number of years since it formed.

Front

How do geologists use strata?

Back

Strata help identify rock types and fossil ages.

Front

What is a scientific theory based on?

Back

A scientific theory is based on repeated confirmation through evidence.

Front

What is the difference between absolute age and relative age?

Back

Absolute age is the exact age in years, while relative age is the age of a rock layer compared to others.

Front

What are isotopes?

Back

Isotopes are variants of a particular chemical element that have the same number of protons but different numbers of neutrons.

Front

What is the significance of fossils in geology?

Back

Fossils help determine the relative ages of rock layers and the history of life on Earth.

Front

What is the principle of uniformitarianism?

Back

The principle that the same geological processes that operate today also operated in the past.

Front

What is a geologic time scale?

Back

A system of chronological dating that relates geological strata to time.