8.E.2

Front

What is the Law of Superposition?

Back

The Law of Superposition states that in undisturbed sedimentary rock layers, younger rocks lie above older rocks.

Front

What are fossils?

Back

Fossils are traces or remains of organisms that lived long ago.

Front

What is relative dating?

Back

Relative dating is the method of placing rocks in order from youngest to oldest based on their position in layers.

Front

What is an index fossil?

Back

An index fossil is a fossil that is used to define and identify a particular time period in the geological time scale.

Front

What is the significance of the Law of Crosscutting?

Back

The Law of Crosscutting states that if a geological feature cuts through another, the feature that has been cut is older.

Front

What is an unconformity?

Back

An unconformity is a surface that represents a gap in the geological record, indicating that rock layers were eroded or not deposited for a period of time.

Front

How do geologists use fossils in relative dating?

Back

Geologists use fossils to correlate the ages of rock layers and to identify the relative ages of the rocks.

Front

What is the difference between absolute dating and relative dating?

Back

Absolute dating provides a specific age of a rock or fossil, while relative dating places rocks in order without providing exact ages.

Front

What is the principle of original horizontality?

Back

The principle of original horizontality states that layers of sediment are originally deposited horizontally under the action of gravity.

Front

What is a sedimentary rock?

Back

Sedimentary rocks are formed from the accumulation and compaction of mineral and organic particles.