Scientists have provided data that, in their opinion, prove the reality of a supercontinent that existed 600 million years ago.
Geological professor Damian Nance developed the theory of supercontinents back in the 1980s. According to her, the oldest supercontinent - Colombia - existed about one and a half billion years ago, and after it, 400 million years later, Rodinia was formed. This theory was accepted by the scientific community, but the subsequent formation of the Earth, which included the supercontinent Pannotia, was criticized for a long time. Nance now believes that he and a colleague have presented results that directly demonstrate the reality of the ancient continent.
According to him, a collision or rupture in the earth's surface leaves clear and hidden traces. For example, the impact of two continents, as a result of which a new one is formed, is accompanied by the rise of mountains. The same goes for breaks. When spreading, continents leave rifts - large depressions in the earth's crust. In addition, there are implicit traces of destruction. Supercontinents affect the level of the World Ocean, its chemical composition and climate - all these processes create isotopic signals that can be easily found in rocks. Nance explains:
“Today we know a lot more about what happens in the layer between the surface and the earth's core. It now seems clear that the life cycles of supercontinents play a huge role in the circulation of matter in the earth's mantle. This, in turn, affects the Earth's magnetic field. We now understand how to track the cycles of supercontinents."
In this case, according to the scientist, "isotopic proxy signals" unmistakably indicate the existence of Pannotia. "By ignoring these proxy signals," the scientist writes, "we ignore the changes taking place in the mantle." The time period that affected the formation of Pannotia, according to Nance, was accompanied by changes in the Earth's ocean, atmosphere and biosphere, as previously suggested.
Alexey Evglevsky