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Relative Age
Fossils
Absolute Age
Geologic Time Scale
More Geologic Time Scale
100

This is the age of a rock as compared to another rock.

What is Relative Age?

100
These are any remains, trace, or imprint of a living thing that has been preserved in Earth's crust.
What are fossils?
100

Scientists measure this to determine the exact age of fossils.

What are radioactive elements/half-life?

100

These are the Three Era's of the Phanerozoic in order from oldest to newest.

What are Paleozoic, Mesozoic, and Cenozoic?

100

This is how the Dinosaurs became extinct.

What are an asteroid impact and volcanic eruptions?

200
This idea states that lower layers of rocks in a series are older and upper layers of rocks are younger.
What is superposition?
200

Most often, fossils are formed in this.

What is sedimentary rock?

200

This is the other method of determining an age of a fossil that is not exact.

What is relative age?

200
This is how long ago the Earth was formed.
What is 4.6 Billion Years ago?
200
Several of these cold periods have occurred during the Cenozoic Era.
What are ice ages?
300

A rock that has either formed on top of another rock or when magma fills a crack formed in older rock.

What is a younger rock?

300
Specific fossils are the remains of living things that were widespread but only lived for a short period in Earth's history.
What are index fossils?
300

This is the age, in years, of a rock which is determined by comparing the amount of original element to the amount of decay product.

What is Absolute age?

300

These are the first living organisms.

What is bacteria?

300

This is the Epoch that we are living in now.

What is the Holocene?

400

Sometimes telling the relative age of rocks is not as simple as looking at the layers because the crust can do this over the course of time.

What is move, tilt, fold, crack, overturn? (any of these answers works) 

400

These are footprints or burrows left by ancient organisms .

What are trace fossils?

400

This is the amount of original element left after the first half-life passes.

What is 50%?

400

This is the names of the 4 major Eons

What is Hadean, Archaen, Proterozoic, and Phanerozoic Eons.
400

The time period with giant swamps over the whole Earth that we attribute to giving us fossil fuels

What is the carboniferous Period?

500

Most fossils form in this type of rock.

What is sedimentary rock?

500
The soft parts of organisms decay quickly, but fossils form out of the harder parts of the organism. These are 3 examples.
What are teeth, bones, shells, seeds, pollen grains, wooden stems. (name 3 for the points)
500

This is the time it takes for half of the mass of an original element to change into a new product.

What is Half-Life?

500
This is the Era during which dinosaurs roamed the Earth.
What is the Mesozoic Era?
500

This is the 4 divisions of time in order from longest to shortest.

What is an Eon, Era, Period, Epoch?