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Alan4discussion's Avatar Jump to comment 5 by Alan4discussion

Comment 4 by ridelo

30% O2! What caused that amount of oxygen? Too many plants, too little animals?

Probably the reduction of atmospheric CO2 and the deposition of carbon in sedimentary layers, without decomposition recycling it to the atmosphere - thus releasing free oxygen.

Wildfires should have been really wild in those days.

Those are limiting factors on Earth's atmospheric oxygen levels. Surface carbon compounds become progressively more liable to fires, as O2 levels increase.

Air pressure can also be a factor, in respiration and flammability.

Sat, 09 Jun 2012 21:41:16 UTC | #946645