The Oldest Crater Formed As A Result Of Meteorite Impact 2.2 Billion Years Ago Is Discovered in Australia
The Oldest Crater Formed As A Result Of Meteorite Impact 2.2 Billion Years Ago Is Discovered in Australia Scientists have discovered the oldest crater to have been formed by a meteorite impact in Australia. This finding may be indicative of how an ancient ice age ended on our planet.
The Earth is estimated to have formed 4.5 billion years ago, while a 70km-wide meteorite struck the Yarrabubba region in Western Australia 2.29 billion years ago.
The researchers came to this conclusion by studying minerals found in rocks in this region.
The fact that an ancient warming phase occurred on Earth coincided with the impact period suggests that this warming may have started due to the impact of the meteorite impact.
The results of the study, by Curtin University in Australia, were published in the journal Nature Communications.
The crater, located in the arid region west of Australia, was first discovered in 1979, but geologists had not conducted any research into the crater’s age.
Due to billions of years of erosion, the crater is not visible to the naked eye today. However, measurements in the magnetic field indicate that the crater is 70 km in diameter.
“This area is quite flattened because it’s so old, but the rocks there are quite different,” says Professor Chris Kirkland.
How Was The Age Of The Crater Determined?
Zircon and monazite crystals in the rocks were examined to determine when the meteorite struck.
Prof. Kirkland says the impact on rocks can be read like “rings on tree trunks.”
The crystals contain trace amounts of uranium. Uranium deteriorates over time and turns into a lead. The time of impact can also be determined by calculating how much time this transformation takes.
The crater Vredefort in South Africa also dates back 2 billion years. But the crater in Australia was found to be at least 200 million years older than him.
Prof. There may also be older craters that have not yet been discovered, Kirkland says, but the fact that the crater wall has eroded over time makes these discoveries and findings of Earth’s past difficult to uncover.
if It Hit A Glacier, It Might Have Brought The End Of This Era
The researchers say it was just around the time the meteorite struck that the Earth began to warm, and this could have been the result of the impact.
Scientists believe that before it hit, the Earth was largely covered by glaciers, and then it started warming rapidly and the ice sheets melted.
Prof. Kirkland said: “The Age of the crater coincides with the end of that ice age. Therefore, the impact of the impact may have led to significant changes in the Earth’s climate,” he says.
According to computer modeling used by the research team, the meteorite must have hit an ice sheet about a mile thick that encircles the Earth. It is estimated that massive amounts of water vapor and greenhouse gases were released into the atmosphere by this impact.
This is thought to have contributed to the warming of the earth during this period when oxygen was only newly formed in the Earth’s atmosphere and complex living things had not yet formed.
Prof. Kirkland said: “We were thrilled that the crash was so old. But finding this connection to other events on earth made this discovery much more interesting,” he says.
Another theory is that volcanoes are active, releasing abundant carbon dioxide into the atmosphere and causing the earth to warm up.