Unit 3 Geological Time

The Geologic Time Scale is a record of what?

• old geologists
• sweet geology music
• the known history of rocks and fossils
• a list of every living thing ever

Which of the following statements about the fossil record is true?

• all organisms become fossils
• organisms having soft body parts make up most of the fossils
• all organisms that have shells become fossils
• the fossil record is incomplete

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

How old do Paleontologists believe the Earth is?

• 2015 years old
• 3.6 billion years old
• 4.6 billion years old
• 4.6 million years old

What type of rock do fossils form in?

• Igneous
• Sedimentary
• Metamorphic
• Classic

Paleozoic, Mesozoic & Cenozoic are all

• Epochs
• Eras
• Periods
• Eons

Scientists chose where units of geologic time began and ended based on major changes in life forms at certain times.

• true
• false

The disappearance of a species.

• Evolution
• Extinction
• Migration
• Mutation

What determines when an era or period begins or ends? 

• Climate Change 
• New Species 
• Mass Extinction 
• Single Extinction 

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