大氧化事件











地球大气O2增加. 红线与绿线表示估计的范围，以十亿年(Ga)为单位.
阶段 1 (3.85–2.45 Ga): 实际上大气中没有 O2. 大洋仍为缺氧的，可能在浅海的O2有例外.
阶段 2 (2.45–1.85 Ga): O2 被产生，且增加到0.02至0.04 atm, 但被海洋与海床岩石吸收.
阶段 3 (1.85–0.85 Ga): O2增加到饱和了海洋耗氧，但被陆地表面吸收，氧气含量没有明显变化。
阶段 4与5 (0.85–present): O2累积.[1]


大氧化事件（Great Oxygenation Event ），也有氧化灾变（Oxygen Catastrophe or Oxygen Crisis）等不同称呼，是指约26亿年前，大气中的游离氧含量突然增加的事件。这一事件的具体原因尚不得知，目前只有若干种假说能加以解释。大氧化事件使得地球上矿物的成分发生了变化，也使得日后动物的出现成为了可能。[2]



相关条目



  • 藍綠藻

  • 休伦冰河时期



参考文献





  1. ^ Holland, Heinrich D. "The oxygenation of the atmosphere and oceans". Philosophical Transactions of the Royal Society: Biological Sciences. Vol. 361. 2006. pp. 903–915.


  2. ^ 科学家揭开地球早期大气氧气起源之谜[永久失效連結]









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