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海洋与大气间的交换作用是海水获得自由氧的主要途径,大气圈的氧浓度决定了海洋氧含量和海水氧化界面深度,并对海水化学条件和早期生命演化具有至关重要的影响。大量研究认为,海洋表层的氧化发生在约1.84Ga,明显滞后于约2.35Ga的第一次大气圈成氧事件(GOE)。从1.84Ga到约0.8Ga发生的第二次大气增氧事件之前,在长达10亿年的地质时期中,大气圈含氧量相对稳定,仅相当于现代大气圈水平(PAL)的5%~20%,因而海水的氧化界面深度有限。由于氧化界
The exchange between the ocean and the atmosphere is the main way to obtain free oxygen in the seawater. The oxygen concentration in the atmosphere determines the oxygen content of the ocean and the depth of seawater oxidation interface, and has a crucial influence on the chemical conditions of seawater and the evolution of early life. Numerous studies suggest that the oxidation of the ocean surface occurs at about 1.84Ga, significantly behind the first atmospheric aerobic event (GOE) of about 2.35Ga. Before the second atmospheric aerosol event from 1.84Ga to about 0.8Ga, atmospheric oxygen content was relatively stable over the 1 billion-year geologic period, corresponding to only 5% of the modern atmospheric level (PAL) ~ 20%, so the depth of oxidation of seawater is limited. Due to the oxide community