Earth's Past

The age of an object in relation to the age of other objects.

• Absolute Age

• Relative Age

• Index fossil

• Trace fossil

The principle that a sedimentary rock layer is older than the layers above it and younger than the layers below it if the layers are not disturbed.

• Law of Superposition

• Law of Crosscutting Relationships

• Principle of Lateral Continuity

• Principle of Original Horizontality

What is a fossil?

• Foot prints, burrows, or other impressions made by animals that give use clues to how they lived.

• When things die and their remains are buried.

• The preserved remains of an organism.

• The age determined by the things around it.

What is 'half-life'?

• The age determined by the things around it.

• The age of an igneous rock.

• The age determined by radioactive dating.

• The time it takes for 1/2 of the radioactive atoms to decay in an element.

Geologists use radioactive dating to determine THE ABSOLUTE AGE OF ROCKS.

• True

• False

 Absolute age is the true age of something compared to something else.

• True

• False

_______________is the method of determining the absolute ages of rocks.

• radioactive dating

• carbon-14 dating

Which of the following is evidence that supports continental drift?

• the presence of penguins at both the equator and Antarctica

• fossils of the same plant have been found on several continents

• the presence of glacial features in Antarctica

• the presence of volcanic rock in Antarctica

The Law of Superposition helps scientists to determine what?

• The absolute age of rock layers

• The age of fossils

• The relative age of rock layers

• the super powers of rocks

Index fossils help determine relative age through correlating rock layers.

• True

• False