Relative and Absolute Dating Flashcard Review

Front

What is relative dating?

Back

Relative dating is a method used to determine the age of rocks and fossils in relation to one another, without determining their exact age.

Front

What is absolute dating?

Back

Absolute dating is a technique used to determine the actual age of a rock or fossil, often through methods like radiometric dating.

Front

What does the law of superposition state?

Back

The law of superposition states that in an undeformed sequence of sedimentary rocks, the oldest layers are at the bottom and the youngest layers are at the top.

Front

Define unconformity in geology.

Back

An unconformity is a break in the geologic record that occurs when rock layers are eroded over time, resulting in a gap in the geological timeline.

Front

How do sedimentary rocks typically form?

Back

Sedimentary rocks usually form through the accumulation and compaction of sediment, typically in horizontal layers.

Front

What is the significance of index fossils?

Back

Index fossils are fossils of organisms that were widespread but only existed for a short period of time, used to date and correlate the age of rock layers.

Front

Explain the concept of cross-cutting relationships.

Back

Cross-cutting relationships state that if a geological feature cuts through another, the feature that has been cut is older than the one that cuts across it.

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 geologic time scale?

Back

A geologic time scale is a system of chronological dating that relates geological strata to time, used to describe the timing and relationships of events in Earth's history.

Front

What is the difference between a rock layer and a fossil?

Back

A rock layer is a distinct layer of sedimentary rock, while a fossil is the preserved remains or traces of ancient organisms found within rock layers.