Scientists at Curtin University (Australia) have found that catastrophic eruptions began to occur on Earth after a geological lull 2.2 billion years ago. They were the reason for the emergence of Colombia - the first supercontinent, which is located in the northern hemisphere of the Earth. The researchers' article was published in the journal Nature Geoscience.
Tectonic processes that took place at the beginning of the Paleoproterozoic era (about 2.4 billion years ago) led to the emergence of supercratons - large temporary geological structures consisting of ancient platforms (cratons). However, about 1.6 billion years ago, the first supercontinent, Colombia, emerged.
Analysis of the stratigraphic columns, which show a rock bedding sequence 2.4-2.2 billion years ago, has shown a period of calm, when geological processes such as magma eruption, igneous metamorphism and mineralization almost stopped. Such "breaks" were explained either by poor preservation of the material, or by some changes in the crust and mantle of the Earth.
Scientists have shown that a magma lull did occur because the rate of folding and sedimentation also decreased during this period. However, 2.2 billion years ago, the decline gave way to a new period of magmatism, which was very different from other similar processes before the calm. A large amount of material was ejected from the Earth's mantle as a result of massive eruptions, which contributed to the emergence of the first hemispheric supercontinent.