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Alichur crater.

Natural sights in Tajikistan.

“Learn from yesterday, live today, hope for tomorrow. The main thing is to never stop asking questions... Never lose your sacred curiosity.”

Albert Einstein.

Nature of Murgab region.

The Alichur crater is located at an altitude of 4122 meters above sea level, located on the southern slope of the Alichur ridge, 756 meters west from the right bank of the Bazar-Dara river, 6.1 kilometers to the south and slightly east of the Bazar-Dara pass at an altitude of 4564 meters above sea level, 9.5 kilometers north of the Alichur – Murgab highway in the Murgab district of the Gorno-Badakhshan Autonomous Region in the eastern part of Tajikistan. 
The Alichur crater is located 80.1 kilometers southwest of the Murghab crater. The Alichur crater is located in the upper reaches of the valley of the Bazar-Dara River, the right tributary of the Alichur River. Bazar-Dara is a typical glacial valley of the Eastern Pamirs with a leveled bottom and soft gentle slopes.
Almost at the watershed ridge of the ridge of the same name, several glacial cirques have been preserved - the sources of the former Bazar-Dara glacier. Throughout the entire valley one can also observe the remains of ancient moraines: either in the form of ramparts blocking the river bed, or in the form of hilly elevations pressed to the bases of the slopes.
On the right bank of the Bazar-Dara gorge, on one of these coastal moraines, at an altitude of about 25 meters above the river, the crater itself is located. It was discovered almost by accident, solely due to its perfectly regular, round shape.
In the early 70s, geologists, studying aerial photographs of the southern slopes of the Bazar-Dara ridge, drew attention to this unusual structure. Subsequent ground study showed that the diameter of the crater is no more or less than 115 meters, and the diameter of the flat bottom is 80 meters.
The depth of the crater turned out to be insignificant - only 16 meters, and this circumstance for a long time did not allow it to be seen from the surface in the bizarre relief of moraine piles. In addition, the funnel-shaped topography of the crater is somewhat disturbed by the watercourse descending from the slope of the valley: part of the eastern wall of the crater is washed away, which allows you to easily enter it even by car.
The smooth, as if compacted bottom of the funnel is covered with fine rubble of mudstones and sandstones. The nearest bedrock outcrops of these rocks are located about two hundred meters along the slope of the valley and belong to the Upper Triassic.
Apart from them, there is nothing in the vicinity of the crater, which means that there are no conditions for karst subsidence that could cause the appearance of such rounded shapes. As is known, karst develops only in strata of easily soluble rocks (we paid attention to this phenomenon in the first chapters of the book).
All geologists are a little skeptics, and therefore, during the first personal acquaintance with the Alichur crater, they tested not so much the hypothesis of its cosmic origin, but rather the possibility of formation due to some other geological processes.
The most suitable method was thermokarst - seasonal thawing of frozen soil (or ice) followed by subsidence of the soil. This assumption is not without meaning, since the Eastern Pamirs belong to permafrost areas.
Typically, thermokarst depressions are filled with melt water with the formation of rounded “saucers” - lakes. Such lakes are found in abundance in the Alichur Valley, and one of them, connected by channels to the river, is known to any Pamir traveler.
This is Akbalyk (Kyrgyz for “white fish”) - a lake like an aquarium, it is so crowded with fish. But thermokarst is limited only by the Alichur valley itself; in its tributaries, in particular in Bazar-Dar, this process has not become widespread.
So, having rejected for various reasons some other proposed options for the origin of the Alichur crater, geologists involuntarily had to return to the idea of meteorite formation. And already in the summer of 1976, a special expedition was organized, the main purpose of which was to search for meteorite matter in the crater area, as well as other signs indicating its extraterrestrial origin.
This amateur expedition included not only experienced Pamir geologists, but also students and schoolchildren who are interested in geology. The search for meteorite matter was carried out both with mine detectors, which are sensitive to the presence of metal, and with specially designed magnetic “staffs”.
But, alas, apart from abundant ferruginous ocher and small pieces of ferruginous rocks, nothing can be collected managed. The data from the spectral analysis of surface samples also turned out to be disappointing: the contents of iron, cobalt and nickel (the main components of iron meteorites) in them were almost the same as those usual for the entire Bazardary valley.
In the situation that arose, the easiest way was to assume that if the meteorite substance was not found on the surface, then it could well have been preserved at depth. It is a thankless task to dig holes at an altitude of 4122 meters, but the expedition members had no other choice.
Together, we managed to reach a depth of three meters; beyond that, the walls of the pits became unstable and quickly crumbled. And yet the work of the diggers was not in vain; Very interesting details of the structure of the crater, inaccessible to superficial observations, were revealed.
First of all, it was found that the true depth of the crater is much greater than measured from the surface. If up to the 2.5 meter mark the filling of the crater contained the same material as at the top (thin crushed sandy-clayey rocks), then deeper brown-gray plastic clays penetrated with ice crystals appeared.
The thickness of the clays, as well as the nature of the bedrock beneath them, remained, however, unknown, but the clays themselves turned out to be unusual - typically lacustrine. It turned out that after its formation, the crater for a long time contained an entire lake reservoir, and only very recently (calculated perhaps several thousand years) the eastern shore of the lake was washed away and the reservoir ceased to exist.
Thus, the real depth of the crater is unlikely to be less than 20 meters. Well, what about meteorite matter? Unfortunately, he was not found at depth. Moreover, subsequent geophysical work did not reveal any noticeable magnetic anomalies. 
Geographic coordinates of  Alichur crater: N37°52'31.95" E73°24'25.71"

If you are using geographic coordinates for Google Earth or Google Maps navigation systems, you must remove the last two digits from geographic coordinates and " (hundredths of a second) and enter the result in the input line. Example: N51°44'09.67" E72°39'40.81" = N51°44'09 E72°39'40

Baratov Rauf Baratovich, Novikov Valery Petrovich. “Stone miracle of Tajikistan.” 2nd edition revised and expanded. Dushanbe: Ifron, 1988.

Photos by:
Alexander Petrov.