Oxygen in Early Earth's Atmosphere
One of the biggest problems for evolutionary origin of life speculations is the presence of oxygen. It cannot exist at the beginning because life could not begin to evolve in the first place, so evolutionists have to keep moving the dates for when oxygen first appeared. Although disputed (molecular evidence is blurry after alleged billions of years, I reckon), there is geologic evidence that oxygen has been there all along — just like biblical creationists have said. Now there is additional evidence supporting a very early date for the presence of oxygen in Earth's atmosphere. That's how it was created in the beginning.
Evolutionists have claimed that the early atmosphere during the Archean, older than 2.5 Ga within their timescale, contained no oxygen. Oxygen in the atmosphere will oxidize any developing organic molecule and make it non-biological. After about 2.4 Ga, the evolution of photosynthetic bacteria caused atmospheric carbon dioxide to be replaced by oxygen, which rapidly accumulated to form a substantial portion of the current atmosphere oxygen. Evolutionists term this the Great Oxidation Event (GOE).To read the rest, take a deep breath and click on "Did the early Earth’s atmosphere contain oxygen?"
However, the timing of the GOE has been under debate. Some believe that the GOE occurred a billion years earlier. One of the problems in resolving the debate is that the Archean is so long ago and the evidence is sketchy and difficult to interpret. Moreover, evolutionists assert that billions of years of evolution has obscured the molecular vestiges of the early events.