Planet Study: This Is How Earth Existed Without Oxygen 2.33 Billion Years Ago

Earth's initial 2 billion years of history indicate the absence of air. In a new study, it revealed that the atmosphere's first inflow of oxygen was experienced on Earth 2.33 billion years ago. Such period signifies the beginning of the Great Oxygenation Event, and was then followed by the succeeding growth in the history of Earth.

The earth's first increase in the atmospheric oxygen, while only small, happened within 1 to 10 million years, beginning a flow of events, which would result in the advent of multicellular life. According to senior author Roger Summons, it is the beginning of the long period that reached in complex life. Summons also added that it took 1.7 billion years for the animals that are the same with those at present. However, the existence of the molecular oxygen in the atmosphere and the ocean shows that the organisms that breathe oxygen can succeed.  

Although oxygen was absent in the atmosphere, it was possibly preparing in the oceans as the cyanobacterial photosynthesis byproduct three billion years ago. But, as explained by Summons, the oxygen in the ancient ocean may have suddenly been sucked up by the ferrous iron and other sinks, which have kept it from going into the atmosphere, according to MIT.

The change with the Great Oxygenation Event or GOE has signified the onset of the permanent presence of oxygen in the atmosphere. Recent estimates have put the beginning of the GOE at 2.3 billion years ago, although with doubts of tens or hundreds of million years.

Earth's first oxygen buildup in the atmosphere has been found to be comparatively rapid. The oxygen collected in concentrations that are high enough are expected to have an effect on rocks after 10 million  years. However, such weathering process, would have filtered more specific metals and sulfate into waterways and the oceans. As explained by Summons, it would take time before the system of the earth would be able to reach a new stable state, through the dumping of organic carbon and surpass the increased thresholds of oxygen required to promote biological evolution, Science Mag reported.