Fossil Record and Geologic Time Scale

How old is the Earth?

• 4.5 million years old

• 4.5 billion years old

• 200 million years old

• 200 thousand years old

How do scientists know how old the Earth is?

• They studied the layers of the rock to determine how old the Earth is.

• They studied the stars and formation of the planets.

• They studied the atmosphere and weather patterns on Earth.

• All of the above.

In layers of sedimentary rock, the _________ layer is usually at the bottom. Each higher layer is _________ than the layers below it.

• oldest, younger

• youngest, younger

• youngest, older

• oldest, older

The Era when humans first appeared was...

• Mesozoic

• Cenozoic

• Paleozoic

• Precambrian

Which is the most recent era of time- the one that we are currently in?

• Cenozoic

• Mesozoic

• Paleozoic

• Precambrian

Which era lasted the longest in Earth's history?

• Cenozoic

• Mesozoic

• Paleozoic

• Precambrian

Which Principle of Geology explains why the older layers of rock are found at the bottom, and the younger layers are found on the surface of Earth?

• Law of Superposition

• Law of Cross-cutting relationships

• Law of Inclusion

• Law of Original Horizontality

Which Principle of Geology states that igneous rocks or faults that “cut” into other rocks are younger than the rock layers it cut into.

• Law of Superposition

• Law of Inclusion

• Law of Cross-Cutting Relationships

• Law of Original Horizontality

Which layer of rock was deposited first?

• A

• B

• C

• D

Which layer is the youngest?

• A

• B

• C

• D