1908 TUGUSKA CATASTROPHE. WHAT WAS IT ANYWAY?

There is a prevailing opinion that this Russian meteorite failed to reach the Earth’s surface as it had turned into gas in the dense layers of the atmosphere. However, some new research concerning the position of the Voronov crater in relation to the felled tree areas allow the inclusion of the mysterious Patom crater within the Tunguska phenomenon affected zone. The crater’s structure is anomalous (i.e. it has a central mound therein), moreover, its circular +rampart has sharp edges, which is characteristic to a young crater. So, it’s quite possible to date its formation as 1908. Some scientists say that the Tunguska meteorite may have been related to Halley’s comet. In the morning of June 30, 1908, many a villager in Central Siberia saw a white-blue eye-blinding ball leaving a wake of fire and smoke. As it seemed to the observers, the ball was traveling from south to north, or to nor’-nor’-east, to be more precise, towards the interfleuve between the Enisei and the Lena riverhead. Fortunately, the site of that terrible burst equivalent to a simultaneous explosion of 500-2,000 atomic bombs or to 10-40 Mt of TNT was in a practically uninhabited location 60 km from the village of Vanavara on the Podkamennaya Tunguska.

At Vanavara houses were destroyed. The people of Kirensk, which is a town on the river Lena, saw a cloud composed of explosion products rising over the taiga as a vertical pillar to a height of at least 20 km. Despite a bright sunny day, the flash of fire was seen from Lena gold fields in the vicinity of the village of Bodaybo. The seismographs at Irkutsk, Tashkent, Tbilisi and Jena (Germany).

It was only in 1927 that the USSR Academy of Science expedition led by L.A. Kulik managed with great effort to work its way through to the site near Vanavara. It worked there during three successive seasons and discovered an enormous area of felled trees where their trunks were lying on the ground in a pattern they were supposed to lie after the impact of the aerial blast wave, but neither the crater, nor the fragments of meteorite substance were found then. Tens of subsequent expeditions also returned without any result: it looked as if the meteorite sort of disappeared, as if the gigantic celestial body just dissipated in the Earth’s atmosphere. Out of numerous hypotheses attempting to explain “the Tunguska event”, the trustworthiest seems to be the one that a small comet of ice and frozen gases collided with our planet: it exploded in the dense layers of the atmosphere not reaching the surface of the Earth. Such a conclusion was made only because not a single fragment of meteorite substance was found on the ground (let alone minuscule magnetic remains discovered during the analysis of soil samples, nor was any crater or trace of the impact found on the site. The mass of the Tunguska meteorite was assessed to have been of many tens or hundreds of millions of tons. During the previous geological epochs such giants did not break through the Earth’s atmosphere. These were typical crater-forming visitors from outer space. But no crater, that could have been a testimony of the impact force, exists, so... or just no trace of the impact of the Tunguska meteorite has yet been found in the Podkamennaya Tunguska and Patom areas.

Earlier, some time back Komsomolskaya Pravda informed its readers about the sensational results of the research undertaken by hunter V.I.Voronov in the Evenk taiga or pine forest. He happened to find another area of flattened forest (apart from what was discovered and examined by L.A. Kulik). To be more precise, he managed to establish the location of that enormous flattened forest area which was discovered by Vyacheslav Shishkov, an engineer of the Omsk Road Department, as far back as 1911, who later came to be known as a writer, author of such famous novels as “Ugryum-Reka” (The Sullen River) and “Emelyan Pugachev”. However, nobody paid any attention to Shishkov’s information about the zone of flattened forest since scientists did not know at that time that the Tunguska meteorite could have left a trace like that. That is why the Shishkov flattened forest just went into oblivion. But V.I.Voronov did more than that. In the fall of 1990, approximately 100 km NW of the area examined by L.A.Kulik the hunter found an enormous crater 200 m in diameter that was covered by a thicket of pine trees. The walls of the crater are 15-20 m high... Does it mean that something eventually reached the Earth? Or is it just a chance coincidence and the crater discovered is of older origin?

Only future expeditions and research can give answers to these questions. However, there is one essential thing that makes the problem extremely attractive: just think, the Voronov crater, the Kulik flattened forest zone and the Shishkov flattened forest zone make up a single area with an axis oriented west-nor’-west, and if we bother to extend it east-south-east for 700 km, the mysterious Patom crater discovered by geomorphologist V.V.Kolpakov will be exactly within the zone in question. The crater was named Patom after the name of its location on the Patom Plateau where two tributaries of the Vitim River (Ugryum-Reka) are flowing, i.e. the Great Patom and the Lesser Patom. The crater is in the taiga thicket on the scope of a mountain 1350 m high 50 km west of the village of Perevoz, which is one of the Lena goldfield centers.

The Patom crater, in contrast to similar forms of relief known to science, is strikingly peculiar because it looks very much like a volcano but contains no trace of erupted in-depth rock. It all consists of fragments and boulders (sometimes several meters thick) of local sedimentary rocks, i.e. Precambrian limestone. The entire mountain is composed of the same limestone, and both inside and outside the crater the limestone contains no trace of a change induced by hydrothermal or any other processes. Nor does the shape of that relief feature look like a classic blast-made meteorite crater. It does not resemble a crater from which the rock was ejected by force of explosion. This is a positive rather than negative relief feature. It reminds of some lunar craters because it consists of a regular circular rampart and a central mound inside.

The crater rising over the endless sea of pine forest produces a striking impression. The geologic survey indicated that there was nothing similar to that crater over the entire Patom Plateau. There are no analogous relief features in other areas of Siberia. Well, just think of it! Suddenly, V.I.Voronov discovers an analogous formation in the flattened forest zone at the Podkamennaya Tunguska River!

By its size, the Patom crater is similar to that found by Voronov: the average height of its circular wall is 20 m; its diameter is 86 m, its elliptic base lengths are 140 and 220 m, the height of the central mound is 6 m, and the diameter of its base is 35 m. The crater is asymmetrical and its longer side is SW oriented, which is exactly the direction from which, according to the opinion of many eyewitnesses, the Tunguska meteorite was traveling.

The form of the crater is very peculiar: something like that can appear in a boiler filled with liquid vapor if a stone is thrown into it or in the pipe of mud volcanoes when the bubbles of gas that come up from the depth burst. The total volume of ground and thrown out rock is about 200,000 m³; In fact, the Patom crater is a free-flow piled funnel-shaped frustrum of a cone with a central mound as a complexity addition.

It has an important feature and that is the sharp edges of its circular rampart. In conditions of permafrost and copious annual rainfall, the crater looks as something very “fresh”: its wall did not collapse anywhere, nor is it overgrown with pine forest vegetation, and, as a geological formation, it looks as something very young, so its birth could easily be dated 1908. In this connection, it is worthwhile remembering that it was from the Lena goldfields that the bright flash was observed and what the people living on the banks of the Lena River saw on the side of the slope was the Patom crater (side view). Its diameter is 86 m, its base dimensions are 140 and 220 m, the height of the central mound is 6 m, and the mound’s base diameter is 35 m.

Perhaps, the celestial body in question was made the mounted boulders of solid methane rather than solid hard iron or olivinite and they scattered loose when it passed through the dense layers of the atmosphere flying 30 km high and some fragments dispensed as flying cassette elements fell out upon the ground within the “zone” extended in the northern direction. If a meteorite flying at a space velocity penetrates the earth, thus creating a rock grinding zone around itself (without a blast discharge) of about one million cubic meters, and if we apply the soil loosening factor for normal explosion processes (1, 2), an increase in the volume of rock mass will amount to 200,000 cubic meters. Calculations have indicated that the depth of such a zone should be over 200 m.

It may happen in the future that a special type of “comet” craters will be identified whose features would reflect the specificity of the composition of comet substance. In this regard, the hypothesis formulated by physicist K.Perebiynos about a relationship between the Tunguska meteorite and Halley’s Comet seems to be the most interesting.

As is known Halley’s Comet reappears near the Earth with an average interval of 76 years. It is likely that there are several concentrations of space bodies along its stretched orbit.

But the question why the Patom crater has no analogies is still there. Nor is there an answer why the Tunguska phenomenon has no analogies either. Why did a positive form of relief emerge (as a result of an explosion!) here? There was a time when a belief prevailed that a peculiar bulging of rocks was observed here while they were ground at the time of impact: after hitting an armor plate, a led bullet is literally “splashed out” in all directions in the form of drops as those of a liquid. The Earth’s atmosphere in by no means an armor shield, but, on the other hand, rifle bullet’s velocities are no match for cosmic velocities. One cannot exclude that fast rotation of falling fragments could sharply change the trajectory from sublongitudinal to sublatitudinal during the final phase.

One can assume that in between the village of Vanavara on the Podkamennaya Tunguska and the village of Perevoz on the Zhuya River there might be young circular craters of the Patom type yet to be discovered that appeared in connection with the fall of the Tunguska meteorite. It is quite possible the so far “designated” affected area extends further to nor’-west. The assumption that the Patom crater emerged through the impact of an intensively degasifying substance of the comet (i.e. ice, solid carbonic acid or methane) capable of further degasifying, possibly, even after the fall, changes the established concepts. Scientists do not know how a shell made of solid carbonic acid penetrating a limestone barrier at a speed of 15-20 km.p.s. and coming to standstill at a depth of 200 m inside that barrier will behave. One can add to the aforesaid that the radiation level of the Patom crater rocks does not differ in anything from that of the surrounding limestone. We failed in finding any particles of meteorite substance in the samples of soil we had taken but succeeded in finding some cosmic-type balls in the soil though in small numbers.

Thus, the unique shape of the Patom crater and its undoubtedly young age in combination with the data collected about the newly found Voronov crater, the west-nor’-west orientation of the traces of the blast as well as the eyewitnesses’ accounts of the blast processes observed in the Lena region – all this allows a suggestion that the area affected by “the Tunguska event” was extremely vast commensurable with the global scope of the phenomena observed. Meteorite craters on the Earth have been studied fairly well.

Well, if the Tunguska meteorite is, in fact, a satellite of Halley’s Comet, the people of Siberia will have a real chance to observe the specificity of the comet’s influence upon the Earth once again in 2060.