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12 Cards in this Set
- Front
- Back
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how did oceans first start
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outgassing water vapor from rocks and then condensation
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when did water first occur
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3.8 bya
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wat was the % of current oxygen occured in diff sec of the precambrian
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1% occured in hadean
10% occured in archean proterozoic same as current oxeygen lvls |
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where did the first crust begin to occur
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at subduction zones
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name of oldest rock and how old is it
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acasta gneiss, 4.03 bya
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archaen techtonics
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small continent masses
plate tech rapid movement growth by accretion |
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wen was most of the crust form
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2.5 bya
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wat is the proterozoic eons and how are they divided
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neo - 1.0 bya - 545 mya
meso - 1.6 - 1.0 bya paleo - 2.5 - 1.6 bya |
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wat is the wilson cycle
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This cycle of opening and closing ocean basins
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how long did oxeygen begin the to get to rich in oceans and iron percipitated
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800,000,000
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wat was tempertures of snowball eart
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-40 C
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what is life
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reproduction - long term
metobolic - life of individual |
