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8 Cards in this Set

  • Front
  • Back
Define Halflife
the time it takes for one half of the parent atoms to decay into the daughter elements
How old are the solar system, oldest continental rocks, and oldest seafloor
solar system is 4.5 byo
oldest cont rock is 4 byo
oldest seafloor is 200 myo
What are the geologic time scale units
Eons > Eras > Periods > Epochs
At what eon and what time did visible life occur
Visible life was first present in the phanerozoic eon which lasts from 570 mya up until present time
What was Wegener's theory and what was his Geographic, Geologic, Climatologic and Paleontologic evidence to support it
Geographic evidence was that there were matching continental outlines

Geologic evidence was that there were the same geologic units across the the continents as well as similar mountain chains across continents

Climatologic evidence was that there were glacial striations in equatorial/tropical positions. There were also coal beds and evaporites

Paleontologic evidence was that there was the same land and fresh water fossils found in different continents

Wegener's reason and argument was continental drift and that the continents plowed through oceanic basins however there was no such evidence of plowing in the ocean basins
Define asthenosphere
a layer of low strength, partially molten, contained in the upper mantle. plastic
Define lithosphere
a rigid layer on top of the asthenosphere
Which is thicker, the continental lithosphere or the oceanic lithosphere