In the heart of the Pilbara region of Western Australia, scientists have discovered the oldest impact crater on our planet. It was created over 3.5 billion years ago. The discovery provides fresh insights into the function that cosmic rocks could play on ancient Earth.
Scientists from Curtin University, Australia and from Geological survey of Western Australia exploring stone layers in the North Pole Dome area of the Pilbara region of Western Australia found evidence of the impact of large-scale cosmic stone from 3.5 billion years ago. Pilbara is simply a place where 1 of the oldest exposed rocks in the planet are located. According to prof. Tim Johnson of Curtin University, this discovery importantly changes the existing assumptions regarding the ancient past of our planet.
The results and description of the studies were published in the diary Nature Communications (DOI: 10.1038/s41467-025-57558-3).
A crater from 3.5 billion years ago
Until now, Yarrabubba crater was considered the oldest impact crater. It is 70 kilometres in diameter and is besides located in the western part of Australia. Scientists at Curtin University and Imperial College London set his age in a five-year-old survey of 2.229 billion years ago (more about this in the text: The oldest impact crater on Earth has been identified).
But in fresh studies, scientists found a fresh evidence holder. They identified it with alleged collision cones – characteristic stone formations that arise from shock metamorphism – transformation of rocks due to a shock wave operating in very short time, immense force and advanced temperature. specified structures are found in the substrate of impact craters and another strong explosions, specified as atomic tests.
"The collision cones are beautiful, delicate, branched structures, akin to the badminton dart. They are the only visible feature of the shock, and in nature they can only arise after a meteor hit,” wrote the authors of the investigation in The Conversation.
Collision cones at a site about 40 kilometres west of the Marble Bar in the Pilbara region were created, as the authors of the publication indicate, erstwhile a large space stone hit the area at a velocity of over 36,000 km/h. The impact created a crater over 100 km wide. Scientists emphasize that this must have been a crucial global event.
"Our observations have shown that there was a thick layer of basalt over the collision cone layer without any signs of shock. This meant that the impact must have been the same age as the rocks we know are 3.5 billion years old," the researchers wrote.
Impact
In the early solar system, all major objects were constantly bombarded by asteroids. The evidence of these strokes can be seen at least on the Moon. On Earth, traces of this period were mostly erased from the surface by continuous erosion and geological processes. But scientists can inactive find ancient craters looking for melted rocks, distinctive structures, or minerals formed under tremendous pressure.
Professor Chris Kirkland of Curtin University admitted that the discovery sheds fresh light on how meteorites shaped the early Earth environment. – The discovery of this impact can explain a lot about how life could have arisen. The impact craters could make an environment friendly to microbiological life, specified as hot water pools – he explained.
He besides added that this radically changes our cognition of the formation of the earth's crust. – A immense amount of energy from this impact could have played a function in shaping the early crust of the Earth, pushing 1 part of it under the other, or forcing magma to climb from the depth of the Earth's coat toward the surface," he added.
Source: Curtin University, The Conversation, photograph Gypsy Denise/ Wikimedia Commons/ CC BY-SA 4.0
