Geologic Record - Flashcard 1

Front

What can be inferred about rock layers with trilobite fossils found high in the mountains?

Back

They were ocean layers that were pushed up by plate tectonics.

Front

What method do scientists use to determine the accurate age of rocks?

Back

Radioactive decay.

Front

What is the system called that organizes Earth's history into units of time based on rock record?

Back

Geologic time scale.

Front

What theory states that sudden, violent events changed the earth?

Back

Catastrophism.

Front

What does James Hutton's statement 'The present is the key to the past' refer to?

Back

Uniformitarianism.

Front

What are trilobites?

Back

Trilobites are extinct marine arthropods that lived during the Paleozoic era.

Front

What is the significance of the geologic time scale?

Back

It helps scientists understand the timing and relationships of events in Earth's history.

Front

What is uniformitarianism?

Back

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

Front

What is the difference between catastrophism and uniformitarianism?

Back

Catastrophism emphasizes sudden events, while uniformitarianism focuses on gradual processes.

Front

What is radioactive decay?

Back

The process by which an unstable atomic nucleus loses energy by emitting radiation.