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
The assumption that the same natural laws and processes that operate in our present-day scientific observations have always operated in the universe in the pas
What is uniformitarianism?
100
Which formed first: rock layers or faults?
What are rock layers?
100
This is a theory of what caused the Dinosaurs to become extinct.
What are asteroid impacts and/or 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
You can infer that these are younger than any rocks they cut across.
What are faults?
200
This is how long ago the Earth was formed.
What is 4.6 Billion Years ago?
200
This is the longest period in Earth's history?
What is the Precambrian Period?
300
This is when magma pieces hardens in rock layers.
What is an intrusion?
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
What causes an organism to appear then disappear in the fossil record?
What is environmental or climate change?
300
These are the first living organisms.
What is bacteria?
300
In what era did birds first appear?
What is the Mesozoic Era?
(in the Jurassic Period)
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
Based on the model, what must have occurred between layers A and B? 
What is erosion?
400
Based on the illustration, Dinosaurs in the top layer, are considered this.
What are younger organisms? or What are complex organisms?
400
This is era in which we currently live in.
What is the Cenozoic Era
400
The fish or marine animals appeared in this Era.
What is the Paleozoic Era?
500
Most fossils form in this type of rock.
What is sedimentary rock?
500
These are extinct marine arthropods that lived over 500 million years ago. They are considered index fossils because they existed on earth for a short period time and were abundant in many locations.
What are trilobites?
500
This is the other method of determining an age of a fossil that is not exact.
What is relative age?
500
Known as the Age of Dinosaurs
What is Mesozoic Era? or What is the Jurassic Period?
500
There have been several ice ages in Earth's history. In what era was the last one?
What is Cenozoic Era?