It turned out that whatever the outer core is made of, it isn't an iron-oxygen mix.
出现的结果是无论外核是什么造就的，但它不是铁和氧的混合。
2
As a way of reconciling these two facts, scientists have hypothesized that nearly all of the oxygen being produced was taken up by iron on Earth's surface.
为了调和这两个事实，科学家们假设，几乎所有产生的氧气都被地球表面的铁吸收了。
3
Something in addition to the iron on Earth's surface must have absorbed much of the oxygen produced by plant life.