As science advances and revealing details are found on our planet, we are getting closer to the year zero in the origins of the Earth. Something that is still under debate is the creation of the continents.
The way our continents appear today is not the subject of debate. That, it is proven, occurred after the separation of the tectonic plates.
In fact, it is known that it is a process in formation and in the future, the lands will continue to separate in the surroundings of our oval circumference.
But the question remains: And before that, what happened? That is what a study carried out by experts from Curtin University would have answered, according to the newspaper’s portal ABC.
The researchers maintain that a meteor shower, of the same magnitude as the one that extinguished the dinosaurs, was responsible for the creation of what we now know as the continents.
Meteorite impacts in the creation of the continents
The team of scientists who led Tin Johnson of the Curtin School of Earth and Planetary Sciencessays that this fact was recorded in the first 1,000 years of the planet’s existence.
This theory had been raised for some time. It was based on an early time in our solar system that they qualify as hostile, because meteorites or asteroids constantly collided with all the worlds, favoring the formation of planets.
However, at that time there was no evidence like that presented by the Curtin experts.
The team of researchers analyzed the rocks of the Pilbara craton, located in Australia. This location in Oceania is one of two (the other is in South Africa) determined to be the only ones that have not suffered fragmentation or deformation in history. It is a geological fossil that they consider to be the best preserved in our existence.
“By examining tiny zircon crystals in rocks from the Pilbara Craton, which represents the best-preserved remnant of Earth’s ancient crust, we found evidence of these giant meteorite impacts,” says scientist Tim Johnson.
“Studying the composition of oxygen isotopes in these zircon crystals revealed a ‘top-down’ process, beginning with the melting of near-surface rocks and progressing deeper, consistent with the geological effect from giant meteorite impacts,” he added.
In this way they found that the craton in Australia was created in three stages. The first of them, dating from about 3,600 or 3,400 years ago, a time when the Earth was only a thousand years old and in which there is a single large impact that formed the plate.
The second, which was recorded about 400 or 600 million years later, where there was a process of stabilization of the core of the crust. While the third passed, less than 3,000 years ago, there was a period of melting and granite formation.
“The continents are home to critical metals such as lithium, tin and nickel, commodities that are essential for the emerging green technologies needed to meet our obligation to mitigate climate change. These mineral deposits are the end result of a process known as crustal differentiation, which began with the formation of the first land masses, such as the Pilbara craton,” says Johnson.
Now comes the part in which the elements found in this preserved craton are compared with the rest of those that have been modified. They hope to find similarities that certify what they have already published.