N.A. Filin
JSC "Central Telecommunication Company", Moscow, Russia. E-mail: filinnik@mail.ru
As early as in the middle 80s, it was conceived by the author that Smerdyacheye Lake is probably of a meteorite nature. By his invitation, a research team from Estonia headed by Yu.V. Kestlane had two visits to this lake. The assumption made by the author was supported by the results of the pursued investigation. The formal activities had then been stopped, but the author kept on episodic studying of Smerdyacheye Lake and the neighboring ones. The depths were measured, and the lakesides were explored. As a result, several dry craters were discovered, and a few glasses were found at 1.5 km from Smerdyacheye Lake. Their impact origin was verified by a further examination conducted at V.I. Vernadsky Institute of Geochemistry.
Following the acquaintance with the works of E.V. Dmitriev on comet meteoritics (http://bourabai.kz/dmitriev/index.htm), the procedures suggested by him were used in testing the soil samples for the purpose of revealing the traces of comet dust. The first sample showed the presence of a great deal of comet markers (streamerglasses) in the soil. Those activities were continued in 2007. The check samples were taken at different places of Shaturskii region, their number averaging from 3 to 30 pieces per square centimeter on the microscope slide. On the sides of Smerdyacheye, Lemeshenskoye, Vlasovskoye (Karpovskoye) Lakes, Beloye and Chernoye Lakes near Borduki village, Svyatoye Lake near Shatura town the amount of streamerglasses varied from 100 to 800 pieces per square centimeter. The distribution of streamerglasses into the depth was studied beside three lakes. Their largest content occurred at 3 to 7 cm below the surface and it was gradually decreasing to the depth of 0.5 m. At lower depths only several streamerglasses were met. The sampling procedure was followed by the work on studying the distribution of streamerglasses in the vicinity of the lakes. The examination revealed a mosaic pattern of their fallout. The most streamerglasses were found near the lakes, their number being reduced away from the lakes. An increase in the amount of streamerglasses to the north or north-west of the lakes can be attributable to the wind direction at the moment of catastrophe or to the action of shock waves.
The revealed traces of cosmic dust around the above-cited lakes enable us to assume a fall of a swarm of comet fragments on the Earth, and the lakes themselves have an impact origin. It has not yet been explained whether those fragments resulted from the destruction of a comet nucleus in the upper atmosphere or they were the parts of a multiple comet nucleus and were falling independently of one another.
To have a clear picture of the comet catastrophe, it is required that widespread investigations should be carried out:
- target search of comet fragments in the zones of ejection from the crater;
- measurement of streamerglasses density throughout the area of their fallout,
having regard to the drift of explosion products by the wind, with the aim to
determine the scope of catastrophe.
A variety of craters, from purely explosive to large depressions, make the crater field in Shaturskii region a unique area for investigating the processes which accompany the fallout of comets on the Earth surface and for elucidation of the phenomena which took place near Podkamennaya Tunguska early in the last century.
