Scientists have revised the age of Earth’s oldest known impact crater, the North Pole Dome crater in Western Australia, down by half a billion years from 3.47 billion years. The crater formed around 2.5 billion years ago when a meteorite struck what is now Australia, beating its nearest rival by roughly 800 million years.
The study used advanced mineral dating techniques to determine the ages of minerals in shatter cones and shocked quartz veins at the site. The researchers found that zircon minerals, which can preserve geological time for billions of years, dated back around 2.7 billion years. This age is consistent with another team’s findings, but contradicts their previous claim of an 3.47 billion-year-old impact.
The North Pole Dome crater remains a record-breaking structure and the only known example from the Archean eon, a time when continents were forming. The corrected age provides new insights into Earth’s history and highlights the challenges scientists face in dating ancient impact craters due to geological alterations over billions of years.
Source: https://www.livescience.com/planet-earth/geology/unequivocal-evidence-of-the-age-of-earths-oldest-impact-crater-turns-out-to-be-off-by-half-a-billion-years