Geological Time Scale

Front

What is a geologic column?

Back

A group of rock layers that are placed in order of their relative ages.

Front

What does 'relative age' refer to?

Back

Determines the order of past events but not the absolute age.

Front

What is 'absolute age'?

Back

The actual age of a rock or fossil, determined using the decay of radioactive elements.

Front

What does extinction mean in geology?

Back

The end of life for a group of organisms, usually a species, and the end of a geologic time (Era).

Front

Why do we know more about the Cenozoic era than the Precambrian Era?

Back

The Cenozoic era is more recent and has left behind more visible evidence such as fossils and geological formations.

Front

What is the significance of the Geological Time Scale?

Back

It provides a framework for understanding Earth's history and the timing of events in the geological past.

Front

What are the main divisions of the Geological Time Scale?

Back

Eons, Eras, Periods, Epochs.

Front

What is a fossil?

Back

The preserved remains or traces of ancient organisms.

Front

What is the difference between relative dating and absolute dating?

Back

Relative dating determines the order of events, while absolute dating provides a specific age.

Front

What is a mass extinction event?

Back

A period in which a significant number of species die out in a relatively short time.