​Remember...

​Speed is important, but accuracy is critical! You're scored on correct answer first then get a bonus for how fast you answer correctly.

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​Try to aim for at least 70% of all questions answered correctly. This is a great review for the assessment tomorrow.

​Uniformitarianism

​Geological processes that occur today are similar to those that have occurred in the past.

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​The same processes that we see today have been occurring in Earth's past.

​Principles of Relative Age Dating

• ​Superposition

• ​Original Horizontality

• ​Lateral Continuity

• ​Inclusions

• ​Cross-cutting Relationships

​Superposition

​In undisturbed rock layers, the oldest rocks are on the bottom.

​Original Horizontality

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

​Lateral Continuity

​Sediments are deposited in large, continuous sheets in all lateral directions.

​Inclusions

​If one rock contains pieces of another rock, the rock containing the pieces is younger than the pieces.

​Cross-cutting Relationships

​If one geologic feature cuts across another feature, the feature that cuts across is older.

​Unconformities

​Breaks or gaps in the rock record.

​Index Fossil

​Species that existed on Earth for a short length of time, were abundant, and inhabited many locations.