The event that allowed to form on Earth complex multicellular life that occurred 2.3 billion years ago. This is the so-called the oxygen catastrophe, during which the concentration of oxygen in the atmosphere quickly and considerably increased. To clarify, when this increase occurred, as well as to explain his background, managed a group of scientists from the United States, China, and South Africa.
To date, the molecular is about 21% of the air breathed by the inhabitants of the Earth’s surface. However, during the first two billion years since the formation of the planet this substance is not contained. The content of oxygen in the air “jumped” 2,33 billion years ago. It was not the last, but the first and most important in the history of the Earth such event. That process was, according to the researchers, for 1-10 million years — not too long from the point of view of Geology period of time. Subsequently, the rise in oxygen concentrations started significantly more complex and lengthy processes that, ultimately, and after 1.7 billion years led to the emergence of complex organisms very similar to those that inhabit the Earth today.
Experts representing the American Massachusetts Institute of technology, China University of Geosciences and the South African University of Johannesburg, wondered what processes provoked an increase in oxygen concentration. It is known that he it is quite widely produced by cyanobacteria, however, almost fully absorbed by the microorganisms inhabiting the water or reacts with iron and other elements. As it turned out, the cause of the changes could be changes in the composition of the Earth’s lithosphere – an iron-magnesium mafic rocks quartz rocks came, which did not enter into a chemical reaction with oxygen, and this contributed to its accumulation
To specify the date of the oxygen catastrophe, also known as the “great oxygen event”, with an error of not more than seven million years, scientists were able through the study of the concentration of the sulfur isotopes in various soil layers of early Paleoproterozoic — the number of these isotopes, it was possible to judge the amount of oxygen in the layer corresponding to the specific period of time.
Their research experts presented on the pages of the journal Science Advances.Related posts: