On November 19, 2014, the whole country learned that a terrible sinkhole had occurred in Solikamsk. On the territory of the slowly dying Klyuchik gardening cooperative, a well with sheer walls has formed, reaching a size of 30 by 40 m. Here, due to previous subsidence of the soil, electricity has already been turned off, and many sites have been abandoned since 2005.
Why there was a failure in Solikamsk
What causes such events that pose a danger to people? After all, it was claimed that at least one country house, which the owners had not yet abandoned, disappeared in the failure. And it was just lucky that the sinkhole formed in late autumn, when the garden plots were empty.
The main reason for the repeated subsidence and failures in this area is rocks. The fact is that under the ground there are powerful layers of rock and potash s alts - the most valuable raw material for the production of fertilizers. The city has been known since 1430, when work began on s alt boiling. Since thenthe specialization of Solikamsk is preserved. S alt mining and fertilizer production are city-forming industries, the main place of work and source of income for the population.
At the same time, it was s alt that became one of the reasons why there was a failure in Solikamsk. Groundwater dissolves it, and cavities form in the bowels of the earth. Also, voids arise as a result of mining. If water enters such cavities, the process of dissolution is also accompanied by leaching of s alts. The voids rapidly increase in size. Often the roof above them cannot withstand its own weight and collapses, forming dips and funnels on the surface of the earth. These phenomena are called karst processes.
History of s alt dips
Perm Territory is one of the main centers of world production of mineral fertilizers. He owes this title to the s alt deposits, concentrated mainly under the cities of Solikamsk and Berezniki. This is where the active mining of potash s alts takes place.
The first major event associated with the dissolution of s alts by groundwater and the collapse of the arch of the formed voids occurred in 1986. Then a real man-made earthquake occurred at one of the Uralkali mines. The formation of a failure and the fall of a multi-ton mass of rocks was accompanied by flashes and an explosion of accumulated gases.
As a result, a funnel was formed, which filled with water in a couple of weeks. As early as in 1988, its depth was estimated at 105 m, and 14 years after its formation it was 52 m.the dissolution and leaching of s alts in the bowels did not stop.
1995 and 1997 were marked by new collapses and, as a result, earthquakes with magnitude up to 4 points. Luckily, there were no casu alties: the disaster did not affect residential areas.
But in 1998-2001, the destruction also affected settlements. Not far from the village of Novaya Zyryanka, a new failure occurred. Severe subsidence was observed near the river port. And along Mendeleev Street in Berezniki themselves, several houses and the building of a boarding school were destroyed. I had to evacuate the population from dangerous territories.
New failures
In October 2006, an accident occurred at the first mine - flooding of the underground mine, which had to be abandoned, even leaving valuable equipment behind. And in July 2007, a collapse of the soil occurred in the industrial zone, forming a funnel measuring 40 by 60 m. Then the failure grew, the length of which reached almost half a kilometer.
Unlike the previous ones, this failure occurred in close proximity to industrial and residential buildings. Only a few meters separated it from the administrative building of the mining department. The buildings of the technical s alt and drying factory were in the danger zone. In the end, the canvas of a part of the Chusovaya - Berezniki - Solikamsk railway collapsed. Traffic along this section was stopped, and a bypass line was subsequently laid.
Tragedy in failure
During 2010-2012, several more dips formed. When trying to sleep one of thema tragic event happened. The wall of the failure collapsed, taking with it two bulldozers and a loader. The driver of the latter did not have time to jump out and died.
And now November 2014 and a new failure. In Solikamsk, residents ask themselves the same question as in Berezniki: will the next sinkhole happen right under residential buildings? How to protect yourself?
So, apart from Berezniki, Solikamsk also found itself in the zone of immediate danger (photo). Failure is just the tip of the iceberg. How big are the voids underground formed by the dissolution of s alts, no one can say for sure yet.
Sinkhole in Yamal
In the summer of 2014, on the Yamal Peninsula, helicopter pilots discovered a hole of incredible depth - more than 200 m. This giant hole is located near the Bovanenkovskoye natural gas field.
And just in November last year, Russian scientists were able to descend to the bottom of this amazing funnel. They managed to take samples of soil, water and air. But there was no answer to the main question: how did such a huge formation appear in the permafrost of the peninsula?
Let's name the main versions of its origin. The first is the fall of a meteorite, the second is an explosion. Scientists suggest that due to the thawing of permafrost, shale gas reserves were released, which escaped to the surface, forming a funnel. At the same time, a gas explosion was also possible, which explains the melted walls of the funnel.
As you can see, sinkholes in the ground are by no means a phenomenonnot rare in nature. The reasons for their formation are most often various natural processes: the dissolution of rocks (karst), the thawing of permafrost. But they intensify with the active economic activity of a person, as the failure in Solikamsk shows. And here the most important thing is to avoid casu alties, to find a reasonable compromise between economic necessity and people's safety.
