Earth's early atmosphere had abundant oxygen (Talk.Origins)
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Free oxygen is fatal to abiogenesis scenarios such as those that Stanley Miller experimented with. Evidence indicates that the early earth had significant oxygen.
Source: Ankerberg, John, Steve Austin, Duane Gish and Kurt Wise. 1990. The creation debate: oxygen -- the deathblow to life?
(Talk.Origins quotes in blue)
1. There is a variety of evidence that the early atmosphere did not have significant oxygen.
The dominant scientific view is that the early atmosphere had 0.1 percent oxygen or less.
Talk Origins is ignoring the abundant presence of oxygen in the same rocks, which is the basis of the claim; therefore it remains unrefuted. The abundant presence of oxygen in the rocks suggests that they formed rapidly in an oxygen rich atmosphere, as opposed to slowly in oxygen poor atmosphere as thought by Evolutionists.
In 2002, the Commonwealth Scientific and Industrial Research Organisation claimed they found evidence of the presence of atmospheric oxygen in rocks 2.7 to 3.5 billion years old. 
2. Free oxygen in the atmosphere today is mainly the result of photosynthesis. Before photosynthetic plants and bacteria appeared, we would expect little oxygen in the atmosphere for lack of a source. The oldest fossils (over a billion years older than the transition to an oxygen atmosphere) were bacteria; we do not find fossils of fish, clams, or other organisms that need oxygen in the oldest sediments.
Another way of looking at this, is that bacteria can get through small cracks and pores in rocks that fish, clams, and other organisms cannot penetrate, so it is no surprise to find only fossil bacteria in deep rock.
This is an excellent example of how the theoretical system being used affects the interpretation of data.