Page 119 - Introduction to Petroleum Engineering
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GEOLOGIC HISTORY OF THE EARTH 105
TABLE 6.1 Geologic Time Scale
Approximate End
of Interval
Eon Era Period Epoch (MYBP)
Holocene (recent) 0.01
Quaternary
Pleistocene 2.6
Pliocene 5.3
Cenozoic Neogene
Miocene 23.0
Oligocene 33.9
Paleogene Eocene 56.0
Paleocene 66.0
Cretaceous 145
Phanerozoic Mesozoic Jurassic 201
Triassic 252
Permian 299
Pennsylvanian 323
Carboniferous
Mississippian 359
Paleozoic Devonian 419
Silurian 444
Ordovician 485
Cambrian 541
Proterozoic 2500
Precambrian Archean 4000
Hadean 4600
Example 6.1 Plate Tectonics
The South American and African plates are about 4500 mi apart. If they began
to separate from Pangaea about 225 million years ago, what is their rate of
separation? Express your answer in meters per year.
Answer
The rate of separation is estimated as the distance of separation divided by the
time it took to achieve the separation:
4500mi × 5280ft = 0 106 ft × 0 3048m = 0 032 m
.
.
.
6
×
225 10 yr mi yr ft yr
Human fingernails grow at approximately 2 cm/yr = 0.02 m/yr.
