Vocabulary
Describes the weather conditions in the area over a long period of time.
Climate
How does the fossil record of animals compare to animals that exist today.
Animals in the fossil record are ancestors of animals that exist today.
Climate
Describes weather conditions in the area over a long period of time.
In 1897, a British scientist proposed that Earth was between 20 and 400 million years old. Based on radiometric dating, scientists now propose a different age for Earth. Based on the most current radiometric dating data, about how old is Earth?
4.6 billion years old
The traces or remains of an organism that lived long ago, most commonly preserved in sedimentary rock.
Fossil
A fossilized structure that formed in sedimentary rock by animal activity on or in soft sediment.
Trace Fossil
What is a geologic column?
A group of rock layers that are placed in order of their relative ages
Geologic processes that happened in the past that can be explained by current geologic processes.
Florida State University has a large collection of ice cores taken from the Antarctic. What can scientists learn by studying these ice cores?
History of Earth's climate
The principle that states that younger rocks lie above older rocks of the layers have not been disturbed.
Superposition
Geologic processes that happened in the past that can be explained by current geologic processes.
Uniformitarianism
A geologist is studying three layers of sedimentary rock in an area. The layers have not shifted from their original positions. The geologist records the relative ages of the rocks. The bottom layer is listed as the oldest. The top layer is listed as the youngest. What did the geologist use to determine the relative ages of the rocks?
The law of superposition
Geologic column
An ordered arrangement of rock layers that is based on the relative ages of the rocks, with the oldest rocks at the bottom of the column.
Why are trace fossils more common than body fossils?
A single animal can leave thousands of traces in its lifetime but will leave only one body when it dies.
An ordered arrangement of rock layers that is based on the relative ages of the rocks, with the oldest rocks at the bottom.
Geologic Column
Trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock.
Fossil
Which of these choices is an example of the way a geologist would use relative dating?
1. Determining the minerals that make up rocks
2. Placing rock layers in order of oldest to youngest
3. Classifying rocks as igneous, sedimentary, or metamorphic
4. Using radioactive isotopes to determine the exact age of rock samples
2: Placing rock layers in order of oldest to youngest
Unconformity
A break in the geologic record that is mad when rock layers are eroded or when sediment is not deposited for a long period of time.
Earth's surface features slowly change over time. For example, sharp, jagged mountain ranges become lower and more rounded over time. What factor or factors is/are responsible for this change in their shape?
1. Deposition
2. Weathering and erosion
3. Movement of continents
4. Collisions between continental plates
A break in the geologic record that is made when rock layers are eroded or when sediment is not deposited for a long period of time.
Unconformity
A long cylinder of ice.
Ice Core
How is the geologic column used in relative dating?
It's an ordered arrangement of rocks from oldest to youngest, with the oldest being on the bottom
Superposition
Can you name three types of trace fossils?
1. Tracks
2. Burrows (pathways or shelters made by animals)
3. Coprolite (animal dung)
Determining whether an object or event is older or younger than other objects or events.
Relative Dating