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Changing Earth

An 8th Grade Science Review

TermDefinition
Mold Fossil The impression left by an organism in a rock, after sediment hardens around the dead organism
Cast Fossil A copy of an organism that is forms when a mold is filled with sediment
Carbon Film When the carbon outline of an organism becomes fossilized
Trace Fossils Is a fossil of the movements or activity produced by an organism
Preserved Remains When parts of an animals remains are preserved instead of decaying
Catastrophism The idea that conditions and organisms on Earth change in quick violent events
Uniformitarianism States that the geological processes that occur today are similar to the ones that happened in the past
Stratigraphy the branch of geology that studies the relative age and order of the layers of rock/soil
Law of Superposition States that the youngest layers on Earth are found at the top, and get older as you go deeper
Relative Age A way of describing how old something is by using a comparison
Index Fossil A fossil of an organism that can be used to help date other organisms
Absolute Dating The numerical age of an object
Radiometric Dating Process to determine the absolute age of an object through the decaying of certain isotopes
Half Life The amount of time it takes for half of the atoms in a isotope to decay
The type of rock that can't be radiometrically dated Sedimentary
Carbon-14 A common Isotope used in Radiometric Dating
The Age of the Earth 4.5 Billion Years
Created by: 21pbrown
Popular Earth Science sets

 

 



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