Chapter 5 Flashcards
Carbon film
The thin film of carbon that shows the outline of an organism
Absolute age
Age,in years, of a rock
Cast
A copy of a new rock
Fossil
Remains or imprints of prehistoric organisms
Half-life
The time it takes for half of the atom in an isotope to decay
Index fossil
Remains of an organism that loved during a specific time that is used to define the age o a particular rock layer
Mold
A cavity on the rock which an organism has decayed
Permineralized fossils
Fossils in which the spaces are filled with minerals
Principle of superposition
If rocks are undisturbed, older layers are under younger layers
Radioactive decay
Breaking down of some isotopes
Radiometric dating
Method used to calculate the actual age of a rock
Relative age
Something’s age in comparison to something else
Unconformity
Incomplete layers in rock sequences
Uniformitarianism
Earth proccesses occurring today are similar to those that occurred in the past
