An international group of scientists has discovered that the oldest Norse rock appeared in Greenland. Denmark, Sweden, Norway and Finland are located in a part of the earth’s crust called the Baltic Shield. To learn more about its origin, scientists from the universities of Copenhagen (Denmark) and Western Australia examined zircon crystals obtained from river sand and rocks in Finland. They reported their findings in the journal Geology.

The researchers concluded that the chemical signatures of the crystals across several parameters matched some rocks found in the North Atlantic Craton in western Greenland, one of the oldest in the world. The resulting features suggest that the Finnish rocks are much older than those previously discovered in Scandinavia. But it also corresponds to the age of the samples obtained in Greenland – about 3.75 billion years.

Geologists have suggested that the Baltic Shield broke away from Greenland and drifted over hundreds of millions of years until it ended up in its current location in Finland. The plate grew there and accumulated new geological material until it became the region of Scandinavia. By the way, according to scientists, in those distant times the Earth could resemble a water world and there was oxygen in its atmosphere.

“Understanding how continents form helps us understand why our planet is the only planet in the solar system with life. After all, we would not exist without mobile granite continents and liquid water on them. Because continents affect both ocean flow and climate, the determining factors of life on the planet,” he says. The study’s first author is Andreas Petersson from the University of Copenhagen.

The work of scientists has helped correct data on the Earth’s past. The most common models assume that our planet’s continental crust began forming when it last appeared, about 4.6 billion years ago. A new study has shown that continents probably formed just a billion years after the formation of the Earth. This is evidenced by some other scientific studies, the authors of which studied particles of the earth’s crust from other parts of the world.

Similar rock fragments have been found in Australia, South Africa and India, for example, but scientists aren’t sure if they all came from the same place and arose independently of each other. More research is needed to find out.