Theories and Principles
According to Uniformitarianism, how does geologic change happen?
What is gradually/slowly
What is a fault
A fault is a break in the rock layers caused by plates pulling apart and one side of the rock layers sliding in relation to the other (break and slide!)
What is the death of a species referred to?
What is extinction
Which is a larger division of time?
What is Eons
Comparing fossils and identifying if they are older or younger based on the position in the rock column.
What is relative dating
What is the approximate age of the Earth (based on the current theory of geologic history)?
4.6 Billion Years Old
What doe scientists think many have caused dinosaur extinction?
What is climate change (meteor strike, dust plume, lack of UV radiation)
What is a fossil formed by an animals movement or activity called?
What is a trace fossil
How many Eras make up the Phanerozoic Eon?
What is 3- Paleozoic, Mesozoic, and Cenozoic
What does a scientist need to know to figure out the absolute age of a rock?
What is the rate of decay of a radioactive element in the rock
What is the principal or rock layer formation that could be described as "younger over older"
Law of Superposition
A small crack in the rock column that magma pushes up into is called a___________
What is an intrusion
What replaces tissue in a petrified fossil?
What is minerals
What was the dominant species of the Mesozoic?
What is Dinosaurs
Describe the law of horizontality.
What is rock layers will be originally deposited in horizontal layers, adding one on top of the other
What is the theory that geologic change happens suddenly?
Catastrophism
Converging (colliding rock layers) usually cause the layers to________
What is fold
Fossils that can be used to accurately date rock layers as they lived for a short time period
What is an index fossil
During what era do we find primarily aquatic species?
What is the Paleozoic
When radioactive isotopes break down into other elements it is called...
What is radioactive decay
Describe the analogy between geologic history and the grand canyon
What is Earth history is written in the rock layers of the grand canyon starting at the bottom and working its way up towards the surface
Converging rock layers that are of different densities often lead to _____________ as one plate subducts under the other
What is tilting
What did scientists learn from discovering marine fossils on a Canadian mountain top
What is the area was once covered by water
Why is important to note the presence of mammals during the Mesozoic in order to understand the Cenozoic dominant class of animals?
In order for mammals to evolve and become the dominant class of animals as they are during the Cenozoic, it is necessary to understand that they were present earlier and were able to become dominant.
What is the method that us used to date once living plant and animal remains?
Carbon-14