Geologists discover astrobleme in Logoisk

13 августа 2017

By Daria Tarasova: Space is much closer than it seems, and the astonishing discovery that geologists made in Logoisk proves it. It is an astrobleme - a crater made by the fall of a meteorite.

In the 1970s, geological research was made in the village of Kuzevichi, Logoisk District, and as a result Belarusian scientists proved that millions of years ago a meteorite fell on our lands. The rocks were not placed horizontally - they were mixed, which is not typical for our region. The minerals stishovite and coesite pointed to the presence of a ‘stellar wound’. They are only formed in conditions of a massive impact explosion. The anomalous zone is 10 to 30 kilometers long.

The meteorite itself was not detected. Perhaps, it collapsed during a collision with the earth and evaporated, or simply lies deeper. Presumably, it was a stone asteroid and it was formed at the Cretaceous-Paleogene boundary, which was the time of mass extinction.

In 1974, a large-scale expedition began there. The study involved not only Belarusian geologists, but also academics fr om all over the Soviet Union. The crater was thoroughly investigated with the help of 28 wells. Diamonds were found there, too, but in the form of dust only, and as such, they are of no value.

Scientists established that the diameter of the asteroid was 628 meters. The speed of the fall was 18 km per hour. The 400 million tons asteroid moved from the southwest to the northeast and rammed a funnel that was 450 meters deep. The power of the explosion was 10 times stronger than that of the atomic bomb.

The collision of an asteroid with the earth inevitably leads to a disaster. When, for example, a fire ball - a large asteroid - collides with the earth at sea, a period of the nuclear winter begins - it lasts several years. This phenomenon is characterized by a sharp decrease in temperature by 8-10 degrees and continuous showers. At that time, there was a sea basin in the territory of Belarus. Hence, a similar natural disaster occurred there millions of years ago.

Today, the ancient meteorite crater is buried and cannot be seen with the naked eye. It is possible to observe the outlines with the help of aerial photography from space. The astrobleme, which is the Greek for a "star wound", has no absolute age, but its relative age ranges from 38 to 60 million years.

The astrobleme is still being studied by Russian scientists. To date, this is the only photo on earth, wh ere fragments of flora existed 38 million years ago. In the picture, there are fossilized diatoms that existed at the time of the explosion caused by the asteroid. They were identified with a microanalyzer.

Today, the Logoisk astrobleme is known all over the world. Belarusian scientists made presentations on it at various conferences in Houston in Rome. There may be other meteorites in the territory of Belarus, but so far, the Logoisk astrobleme is only one that has been discovered and proven to be a crater.