Lesson 1: Analyzing the Rock and Fossil Records

Front

What is relative dating?

Back

A method used to determine the approximate age of a fossil or rock layer in relation to other layers.

Front

What is absolute dating?

Back

A method used to determine the exact age of a fossil or rock layer, often using radiometric techniques.

Front

What is relative age?

Back

The age of a rock or fossil compared to other rocks or fossils.

Front

What is absolute age?

Back

The actual age of a rock or fossil, often expressed in years.

Front

What does the principle of original horizontality state?

Back

Most rock-forming materials are originally deposited in horizontal layers.

Front

What does the principle of superposition state?

Back

In undisturbed rock layers, the oldest layers are at the bottom.

Front

What is lateral continuity?

Back

The principle that layers of sediment initially extend laterally in all directions.

Front

What are inclusions?

Back

Fragments of one rock unit that are contained within another rock unit.

Front

What are cross-cutting relationships?

Back

A principle stating that a rock or fault that cuts through another rock is younger than the rock it cuts.

Front

What is a mass extinction?

Back

The extinction of many types of organisms at the same time.