Clues to Earth's Past

Which of the following is NOT an example of a fossil?

• a petrified dinosaur bone
• a footprint captured in mud
• a seashell found on the beach
• an insect stuck in amber

In which kind of rock do we usually find a fossil?

• sedimentary  rock
• metamorphic rock
• igneous rock

Why don't we know what many ancient plants looked like? 

• They had too many soft parts.
• They were all eaten by dinosaurs.
• There weren't ancient plants.
• They had too many hard parts.

Lily sees a skeleton of a dinosaur at a museum. What is true about the bones that make up the skeleton?

• The bones are made up of minerals.
• The bones are those of the dinosaur itself.
• The bones were formed from mud that hardened.
• The bones are made up of amber.

Used to determine whether an object is older or younger than other objects

• Superposition
• Relative Dating
• Fossil
• Unconformity

A break in the geologic record that is made when rock layers are eroded over a long period of time

• Law of Superposition
• Law of Crosscutting
• Relative Dating
• Unconformity

Traces or remains of organisms that lived long ago

• Fossil
• Unconformity
• Superposition
• Column

What is the law of superposition?

• The age of sedimentary rock not found in the original layers.
• Metamorphic rock is younger than the nearby igneous rock.
• Sedimentary rock in it's original position is older than layers above it.
• Metamorphic rock is older because it was deposited to nearby sedimentary rock.

How does the law of crosscutting explain the age of a fault?

• The fault is younger than the rocks above it.
• The fault is younger than the rocks it cuts through.
• The fault is older than the rocks above it.
• The fault is older than the rocks it cuts through.

Analyze the seashell found in the white layer.  Which statement is true of the rock layer that contains this fossil?

• It could also contain a fossil from the bottom layer.
• It is older than the layers below it.
• It is younger than the layers above it.
• It is older than the layers above it.