An international group of scientists led by the University of Oregon has confirmed in South Africa that the Earth has been almost completely covered by ice for about 2.9 billion years. Scientists talked about it in the journal Geochemical Perspectives Letters.

“We discovered perfectly preserved glacial deposits next to gold mines in South Africa,” the scientists said.

It is this field, which is one of the few that has survived almost unchanged to the present day. According to Ilya Bindeman, a professor at the University of Oregon at Eugene, they are composed primarily of fossilized moraines, that is, pieces of rock left behind by a melting and retreating glacier.

Unique deposits have been discovered under the Witwatersrand, southwest of Johannesburg, the world’s largest gold ore deposit. During the analysis, it was determined that the debris deposits were made by glaciers, and very little in the ice was proof of this judgment. ¹⁸ and a lot ¹⁷ O. These oxygen values ​​indicate negative temperatures at which glaciers form.

Such deposits are among the oldest that scientists have had to study. Probably 2.9 billion years ago, our planet experienced a partial glaciation, during which a significant part of the Earth was covered with a blanket of snow and ice.