1. Week 16

2. Original horizontality Superposition Cross-cutting relationships
1. You can tell that the oldest rocks are at the bottom of an undisturbed rock sequence by using the principle of
Uniformitarianism
Original horizontality
Superposition
Cross-cutting relationships

3. Original horizontality Superposition Cross-cutting relationships
2. The principle that states that the processes occurring today have occurred since the Earth was formed is known as
Uniformitarianism
Original horizontality
Superposition
Cross-cutting relationships

4. 3. In an undisturbed rock sequence, the youngest rock layer is located
At the bottom of the sequence
At the top of the sequence
Below the sedimentary rock layer
Below the unconformity

5. 4. The relative age of a rock layer that contains inclusions is
Older than the source of the inclusions
Older than the layer below it
Younger than the source of the inclusions
The same as the intrusion that cuts across it.

6. Fossils unconformities sills inclusions
5. What are particles eroded from a layer of rock that become incorporated in an overlaying rock layer
Fossils
unconformities
sills
inclusions

7. 6.The Precambrian is the _________ part of the geologic time scale.
youngest
oldest
c. shortest
most recent

8. 7.The first organisms that lived on the earth were
Dinosaur
Birds
Microscopic organism
worms

9. 8.What two gases probably dominated Precambrian Earth’s atmosphere?
Hydrogen
Helium
Oxygen
Both Hydrogen and helium

10. 9. Analyzing fossil chemistry can teach us about
The environment in which the original organism lived
How the fossil moved
The precise age of the original organism when it died
The social structure

11. Warm tropical temperatures Phytoplankton and zooplankton
10. Which of the following causes ocean water to be denser than fresh water?
El Nin’o
Warm tropical temperatures
Phytoplankton and zooplankton
Dissolved substances