کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
6436744 1637608 2013 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The rise of oxygen and the hydrogen hourglass
ترجمه فارسی عنوان
ظهور اکسیژن و ساعت کریستال هیدروژن
کلمات کلیدی
اکسیژن، فرار هیدروژن، تکامل اتمسفر، اکسیژن، سیر تکاملی،
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات ژئوشیمی و پترولوژی
چکیده انگلیسی


- Oxygenation of Earth is caused by hydrogen escape.
- Oxygenic photosynthesis predates the rise of oxygen by several hundred million years.
- The delay is due to titration of easily oxidized, near-surface reduced reservoirs.
- Hydrogen escape applies a bias to biological evolution.

Oxygenic photosynthesis appears to be necessary for an oxygen-rich atmosphere like Earth's. But available geological and geochemical evidence suggest that at least 200 Myr, and possibly more than 700 Myr, elapsed between the advent of oxygenic photosynthesis and the establishment of an oxygen atmosphere. The interregnum implies that at least one other necessary condition for O2 needed to be met. Here we argue that the second condition was the oxidation of the surface and crust to the point where O2 became more stable than competing reduced gases such as CH4. The cause of Earth's surface oxidation would be the same cause as it is for other planets with oxidized surfaces: hydrogen escape to space. The duration of the interregnum would have been determined by the rate of hydrogen escape and by the size of the reduced reservoir that needed to be oxidized before O2 became favored. We suggest that continental growth has been influenced by hydrogen escape, and we speculate that, if there must be an external bias to biological evolution, hydrogen escape can be that bias.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Chemical Geology - Volume 362, 20 December 2013, Pages 26-34
نویسندگان
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