之前认为，氧气最早出现的迹象是在2.3亿到2.4亿年前之前，那时侯正经历着“大氧化事件”

Previously, the earliest indications of oxygen had been from between 2.3 billion and 2.4 billion years ago when the "Great Oxidation Event" occurred.

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这次生物大灭绝事件的发生似乎至少部分是因为大量的火山喷发，火山喷发将大量的二氧化碳喷到大气中。

At least part of the cause of this extinction seems to have been huge volcanic eruptions that poured carbon dioxide into the atmosphere.

youdao

这次生物大灭绝事件的发生似乎至少部分是因为大量的火山喷发，火山喷发将大量的二氧化碳喷到大气中。

At least part of the cause of this extinction seems to have been huge volcanic eruptions that poured carbon dioxide into the atmosphere.

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