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Discovery of World’s Oldest Meteorite Impact Crater Rewrites Earth’s History

Researchers at Curtin University have unveiled what is believed to be the oldest meteorite impact crater on the planet, potentially transforming our comprehension of life’s origins and the geological development of Earth.

This groundbreaking finding originates from an extensive study conducted by the team at Curtin’s School of Earth and Planetary Sciences, in collaboration with the Geological Survey of Western Australia (GSWA). Their research focused on rock formations in the North Pole Dome, located in the Pilbara region of Western Australia, where they uncovered significant evidence indicating a catastrophic meteorite impact dating back 3.5 billion years.

According to Professor Tim Johnson, a co-lead of the study, this revelation marks a pivotal shift in our understanding of Earth’s formative years. “Prior to our study, the oldest verified impact crater was estimated to be around 2.2 billion years old. Our discovery significantly pushes the timeline back,” he remarked.

The team primarily identified the ancient crater through a unique geological feature known as ‘shatter cones’. These cone-like formations are indicative of the extreme pressures experienced during a meteorite collision.

The specific site, located approximately 40 kilometers west of Marble Bar in Western Australia’s Pilbara region, was the result of a meteorite striking the Earth at speeds exceeding 36,000 kilometers per hour. This monumental event would have created a crater measuring over 100 kilometers in diameter, sending debris scattering across the globe.

Professor Johnson elaborated on the implications of their findings: “Large impacts in the early solar system were commonplace, as evidenced by studies of the Moon. The lack of recognition of ancient craters in geological research suggests a significant gap in understanding our planet’s impact history.” He added that this discovery opens the door to the potential identification of further ancient craters in the future.

Co-lead author Professor Chris Kirkland, also affiliated with Curtin’s Earth and Planetary Sciences division, emphasized the discovery’s implications for our understanding of Earth’s primordial environment. He stated, “Discovering this impact site, along with others from the same era, could provide critical insights into how life may have originated. Impact craters likely formed warm, water-rich environments conducive to microbial life.”

Additionally, Professor Kirkland noted, “This finding significantly revises our understanding of crust development. The immense energy generated by the impact could have influenced the formation of early Earth’s crust, potentially leading to one section of the crust being driven beneath another or facilitating the rise of magma from deep within the mantle.” He suggested that these processes may also have played a role in the emergence of cratons, the foundational stable landmasses foundational to the formation of continents.

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