Fossils
Why don’t fossils form in igneous rocks?
Because any fossils in the original rock will have melted when the magma formed.
What do intrusions tell about the relative age of rocks around it?
It is always younger than the rock layers around and beneath it.
What era do we live in today
What is cenozoic?
How is relative dating different from absolute dating?
Relative dating does not give an exact numeric age, but absolute dating does.
What is the main idea of the plate tectonics theory?
That plates are constantly moving.
What is radioactive decay used for?
Tell the exact numeric age of the rock layer it was found in.
How does a fault impact rock layers?
It is older than the layers it cuts through
What time era did the dinosaurs live in?
What is mesozoic
What are index fossils used for?
Fossils used to identify the age of the rock layer they were found in
What is Pangea?
A giant continent that was split up by plate tectonics.
If two fossils are found in the same rock layer, what does this indicate about their relative age?
They were found in the same time era.
How is sedimentary rock different from igneous?
Sedimentary forms when grains of broken rock get glued together underwater. Igneous rock is formed when Magma hardens.
In what era were the first fossils found
What is paleozoic?
How can you tell the relative ages of rock layers?
Using the Law of Superposition, older layers are beneath younger layers.
How are earthquakes used as evidence for the Plate Tectonic Theory?
They show that the plates are constantly moving.
What are the different types of fossils?
-Mold Fossil
-Cast Fossil
-Petrified Fossil
-Preserved Fossil
-Carbonized Fossil
-Trace Fossil
What is a Carbonized Fossil?
A fossil created when an organism is pressed between layers of rock under great pressure
What caused the great dying at the end of the paleozoic?
A big amount of cO2 in the air.
How is the Law of Superposition used?
It states that younger rock layers are usually above rock layers.
Why doesn’t Pangaea exist today?
Plate tectonics moved the continental plates.
What are three characteristics of an ideal index fossil
-Found in one single time era
-Unique looks
-Found in many geological areas
Explain how marine fossils could be found on top of mountains.
The mountain was once in the ocean, it was underwater, and plate tectonics caused it to rise up
What is the longest era of time called
What is Precambrian?
What is an Ice Core?
Sample of ice that can be used to reconstruct a climatic record over the age range of the sample.
How could fossils of tropical animals be found in Antarctica.
Antarctica was once connected to a continent with tropical climate.