Show:
Fossils
relative dating
absolute age
odds and ends
more odds and ends
100
fossilized tree sap
What is amber
100
putting rocks in chronological order from oldest to youngest
What is relative dating
100
putting a number age on rocks
What is absolute dating
100
principle that says the present is the key to the past
What is Uniformitarianism
100
Fossil evidence like tracks and burrows
What is trace fossil
200
asphalt pools in California
What is the Lab Brea Tar Pits
200
Sedimentary rocks originally laid down in a horizontal position.
What is principle of original horizontality
200
time it takes for 1/2 of unstable element to turn into a stable element
What is half-life
200
Man who first proposed that the present is the key to the past
Who is James Hutton
200
organisms that only lived for short time and can be used to help date rocks
What is index fossils
300
Fossilized dung
What is coprolites
300
Oldest rocks on bottom. youngest rocks on top
What is principle of superposition
300
used to date once living matter
What is Carbon 14
300
the stable element that uranium 238 turns into
What is Lead (Pb)
300
how much of the original unstable element would be left after 2 half-lives
What is 25%
400
Found in a glacier
What is frozen
400
crosscutting features are younger than the rocks they cut across
What is the principle of crosscutting relations
400
fancy name for absolute dating using radioactive isotopes
What is Radiometric dating
400
The half-life of Uranium238
What is 4.5 billion years
400
fraction of original unstable element after 3 half-lives left
What is 1/8th
500
turning to stone
What is Petrification
500
when rock layers are missing
What is an unconformity
500
Type of rock used for radiometric dating
What is Igneous
500
The half life of carbon 14
What is about 5700 years
500
Term for when an unstable radioactive element turns into a stable element
What is radioactive decay