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It was long time ago when people, watching the Moon, noticed dark spots
there. Later, the scientists proved this was nothing but craters; there
appearance was caused by the meteorite fall.
There are craters at many of the planets of the solar system and on the
Earth too. The geologists came to know about the existence of many of them long
ago, but they were considered to be volcanic and tectonic craters.
With the development of space technology they managed to get to know
more about the Earth craters. In 1963 the German scientist R.S. Ditz proposed
to use the new term to call this phenomenon: ASTROBLEMA-“star wound”.
The scientists consider about 10 thousand green “scars” to be at the surface of our
planet now but only 110-150 geological structures are called astroblems with
certainty.
The Earth craters being on the platforms and the heights – shields are
in the state of fair preservation. Arizone crater (photo) or Canyon Diablo that
is 1207 meters in diameter and 174 meters in depth and that is situated in the
unpopulated region in the United States is the youngest astroblem the present
day
The Ukrainian shield numbers the most astroblems. 7 astroblems
considered to be at the territory of our country: Boltiyevska, Selenogaiska,
Rotmyrivska, Obolonska, Tornovska. Illinetsk ravine, located at the village of
Lugove Illinetsk region, between the rivers of Sob and Sobyk, in Podillya, (35
km to the south-east from Vinnytsya) is one of the oldest star wounds of the
Earth. It is 400 million years old. It appeared long-long time ago after the
Earth collision with a big celestial body. Its initial diameter was 6,5-7 km
and depth was 600-800 meters. «The traveler of the Universe”, caused this
Earth scar, weighed more than 400 million tons and was 230-300 meters in
diameter. After the collision with the hard rock there was an explosion and the
evaporation of the meteorite as well as of the earth rocks came out of this.
But a great amount of this meteorite and the earth rocks scattered at the moment
of explosion. The leading Ukrainian geologists from Kyjiv with Professor A.A.
Valter at the head discovered the high contents (comparing with the
Earth standards) of nickel, cobalt and iridium and so on in such minerals.
These data gave possibility to determine that our «guest» was ferrous and
siliceous.
Professor Pheophilaktov K.M. was first to mention Illinetsk structure in
1851. It was studied more thoroughly and described in details by V.Ye.
Tarasenko in 1898, but it was only in 70-80s this century that after a long and
thorough research Illinetsk structure was proved to be the astroblem. They
continue to study it even now though tectonic processes, water and air erosion
had a strong influence upon it and there is no ravine as such. You can see only
the burned banks of the rivers Sob and Sobyk at the place of the meteorite fall
but they don’t seem to be peculiar for the ordinary person, who knows
little astronomy and geology. They are rocks and nothing more from the very
first sight…
Helen Pochapska
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