Earth's History

The division of geologic time that makes up about 88% of Earth’s history is called

• The paleozoic era
• the cambrian period
• precambrian time
• permian period

The Cenozoic Era is known as the

• Age of Reptiles.
• age of fishes
• age of evolution
• age of mammals

The most common precambrian fossils area

• marine worms
• trilobites
• stomatolites
• brachiopods

The gradual development of new organisms from preexisting organisms is called

• natural selection
• mass extinction
• evolution
• environmental change

On a geologic column, the oldest rocks

• are on the bottom
• are on the top
• are in the middle
• contain fossils of modern day animals

Scientists have most accurately determined the absolute ages of rock layers by

• factoring rates of sediment deposition.
• using geologic columns.
• using radiometric dating methods.
• determining rates of erosion.
  

What can a scientist assume about a rock layer that matches a similar layer in a geologic column?

• The layers are from the same area.
• The layers contain the same kind of rock.
• The layers were found at about the same time.
• The layers formed at about the same time.
  

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

According to the law of superposition, the oldest fossils are found 

• At the top of the rock layers
• Near the bottom of the rock layers
• In the middle of the rock layers
• Somewhat near the surface

Which of the following is the oldest?

• Layer L
• Intrusion D
• Intrusion H
• Layer E