Transcript Slide 1

Time- a limited period or interval,
as between two successive events.
Seconds
Minutes
Hours
Days
Years
The Earth is thought to be 4.6
billion years old.
Can you grasp how big 1 billion is???
http://www.crunchweb.net/87billion/
1. 1. Relative Time- subdivisions of the
Earth's geology in a specific order based upon
relative age relationships. These subdivisions are
given names, most of which can be recognized
globally, usually on the basis of fossils.
Example: Thanksgiving is between Halloween and New Year’s Eve.
Fossil- remains, impressions, or other
evidence of life
preserved in rock.
1. 2. Absolute Time- numerical ages in
"millions of years" or some other measurement.
These are most commonly obtained via
radiometric dating.
Example: The school year is 180 days long.
mya = millions of years ago
bya = billions of years ago
Example: The following are equal amounts of time
3,800,000,000 years ago
3,800 mya
3.8 bya
Geologic Time Scale
Subdivided into segments of time:
Largest
Eon
Era
Period
Smallest
Epoch
Geologic Time Scale
Subdivided into segments of time:
Youngest
Oldest
3-Eons
Phanerozoic
Proterozoic
Archean
Geologic Time Scale
Subdivided into segments of time:
Youngest
Eon
Era
Phanerozoic
Cenozoic
Mesozoic
Paleozoic
Divided into 3 Eras
Oldest
Geologic Time Scale
Subdivided into segments of time:
Period
Eon
Phanerozoic
Era
Cenozoic
Youngest
Quaternary
Tertiary
Cretaceous
Neogene
Paleogene
Jurassic
Triassic
Mesozoic
Permian
Carboniferous
Devonian
Paleozoic
Oldest
Silurian
Ordovician
Cambrian
Pennsylvanian
Mississipian
Geologic Time Scale
Subdivided into segments of time:
Period
Eon
Phanerozoic
Era
Cenozoic
Youngest
Mesozoic
Paleozoic
Quaternary
Holocene
Tertiary
Pleistocene
Cretaceous
Pliocene
Jurassic
Miocene
Triassic
Oligocene
Permian
Eocene
Carboniferous Paleocene
Devonian
Silurian
Oldest
Epoch
Ordovician
Cambrian