Age
Time Scale
Principles
Hodge Podge
Hodge Podge
100
The exact age of a rock
What is Absolute Age
100
This shows changes in the fossil record
What is the Geologic Time Scale
100
This Principle states that most rock-forming materials are deposited in horizontal layers and are later bent
What is the Principle of Original Horizontality
100
The idea is that events in Earth's past happen suddenlly
What is catastrophism
100
A break in Earth's crust
What is a fault
200
The age of a rock in relation to other rocks
What is Relative Age
200
This is a gap in the fossil record
What is an unconformity
200
This Principle states that in undisturbed rock layers, the oldest rocks are on the bottom
What is the Principle of Superposition
200
This is physical evidence of Earth's past
What is a fossil
200
Organisms that live a short time, in many locations and are easily identified
What is an Index Fossil
300
When finding the absolute age of a rock scientists use radioactive elements and determine how many of this have occurred to calculate the age of the rock, what is "this"
What is a half-life
300
This type of fossil is most useful in determining the age of rock layers
What is an Index Fossil
300
This Principle states that sediments are deposited in large, continuous sheets in all directions, later it may be changed.
What is the Principle of Lateral Continuity
300
The idea is that processes and events on Earth happen today, the same way they did in the past
What is uniformitarianism
300
Which is younger, E the fault, or D the igneous extrusion
What is E, the fault
400
Which radioactive element will be more useful to date a rock from the Paleozoic Era, Carbon-14 or Potassium-40?
What is Potassium-40
400
The sudden disappearance of organisms in the fossil record in a short period of time
What is a Mass Extinction
400
This is the Principle that states if one rock contains pieces of another rock, the rock containing the pieces is younger than the pieces
What is the Principle of Inclusions
400
When molten magma is pushed into layers of rock without ever reaching Earth's surface
What is an Igneous Intrusion
400
When molten magma hardens on Earth's surface
What is an Igneous Extrusion
500
When scientists match layers of rocks or fossils exposed in one geographic area to other areas
What is correlation
500
The record of geologic events and the evolution of life forms as shown in the rock and fossil records
What is the Geologic Time Scale
500
This principle states that if one geologic feature cuts across another geologic feature, the feature that it cuts across is older
What is the Principle of Cross-Cutting Relationships
500
It is currently estimated that Earth is how old
What is 4.6 Billion years old
500
Fossils help scientists determine the _____________ of the area years ago.
What is environment