A scientific team of researchers from two universities, the University of Western Australia (UWA) and the University of Technology of Queensland, found the oldest rocks on the Earth, in Western Australia. The finding revealed the formation of the Australian continent before the formation of tectonic plates, academic sources reported today.
The study was based on the discovery of a deposit of rocks located in the east of Pilbara. There were rocks between 3,600 and 3,400 million years old when it is estimated that the Earth’s crust reached its maximum temperature.
The analysis of the rocks revealed that the old terrestrial crust made a gravitational overturn, which was followed by at least three others during 100-million-year cycles until the tectonic plates developed 3,200 million years ago.
These oldest rocks on the Earth made possible the emergence of the Australian continent
The scientists from the Univesity of Western Australia said in a statement that these rocks are the result of the gravitational instability of the crust derived from the volcanic eruptions and high temperatures of the initial phase of the planet.
The investigation attributes to these episodes of extreme phenomena, the chemical mixture and thermal progression of the old crust, which in the end allowed the emergence of a stable continent, able to sustain the process of formation of the tectonic plates.
The leader of the study, Daniel Wiemer, said that this work shows the particular formation and evolution of the primitive Earth’s crust through these gravitational instabilities.
“We were able to reconstruct the formation of granite-like rocks and their subsequent exhumation, erosion, and sedimentation during the oldest known gravitational overturn,” Wiemer said.
The study, which also included experts from the Queensland University of Technology, was published recently in the journal Nature Geoscience and concluded that these oldest rocks on the Earth formed 3,400 million years ago, when the Earth was in its initial phase as a planet, were responsible for the Australian continent creation.