Many scientific and industrial works are connected with drilling of underground wells. The total number of such facilities in Russia alone is hardly calculable. But the legendary Kola super-deep since the 1990s has remained unsurpassed, going into the thickness of the Earth for more than 12 kilometers! It was drilled not for economic benefit, but out of purely scientific interest - to find out what processes are taking place inside the planet.

The most amazing well in the world is located in the Murmansk region, 10 kilometers west of the city of Zapolyarny. Its depth is 12,262 meters, the diameter of the upper part is 92 centimeters, and the diameter of the lower part is 21.5 centimeters.

The well was laid in 1970 in honor of the 100th anniversary of the birth of V.I. Lenin. The choice of place was not accidental - it is here, on the territory of the Baltic Shield, that the most ancient rocks, whose age is three billion years old, come to the surface.

Since the end of the 19th century, the theory has been known that our planet consists of a crust, mantle and core. But where exactly one layer ends and the next begins, scientists could only guess. According to the most common version, granites go down to three kilometers, then basalts, and at a depth of 15-18 kilometers the mantle begins. All this had to be tested in practice.

Underground research in the 1960s was like a space race - the leading countries tried to get ahead of each other. The opinion was expressed that the richest deposits of minerals, including gold, are located at great depths.

The Americans were the first to drill super-deep wells. In the early 1960s, their scientists figured out that the Earth's crust is much thinner under the oceans. Therefore, the area near the island of Maui (one of the Hawaiian Islands) was chosen as the most promising place for work, where the earth's mantle is located at a depth of about five kilometers (plus a 4-kilometer water column). But both attempts by researchers from the United States ended in failure.

The Soviet Union had to adequately respond. Our researchers proposed to create a well on the continent - despite the fact that it took longer to drill, the result promised to be successful.

The project became one of the largest in the USSR. 16 research laboratories worked at the well. Getting a job here was no less difficult than getting into the cosmonaut corps. Ordinary employees received a triple salary and an apartment in Moscow or Leningrad. Not surprisingly, there was no staff turnover at all, and at least 50 candidates applied for each position.

Down to a depth of 7263 meters, the drilling was carried out using a conventional serial installation, which at that time was used in the extraction of oil or gas. This phase took four years. Then there was a one-year break for the construction of a new tower and the installation of a more powerful Uralmash-15000 installation, created in Sverdlovsk and called Severyanka. In her work, the turbine principle was used - when not the entire string rotates, but only the drill head.

With each meter passed, it became more difficult to drive. Previously, it was believed that the temperature of the rock, even at a depth of 15 kilometers, would not exceed 150 °C. But it turned out that at a depth of eight kilometers it reached 169 ° C, and at a depth of 12 kilometers it was 220 ° C at all!

The equipment quickly broke down. But the work continued without stopping. The task of being the first in the world to reach the 12-kilometer mark was politically important. It was solved in 1983, just in time for the beginning of the International Geological Congress in Moscow.

Congress delegates were shown soil samples taken from a record depth of 12 kilometers, and a trip to the well was organized for them. Photos and articles about the Kola Superdeep were published in all the world's leading newspapers and magazines, and postage stamps were issued in several countries in her honor.

But the main thing is that a real sensation was prepared especially for the congress. It turned out that rock samples taken at a 3-kilometer depth of the Kola well are completely identical to the lunar soil (it was first brought to Earth by the Soviet automatic space station Luna-16 in 1970).

Scientists have long assumed that the Moon was once part of the Earth and broke away from it as a result of a cosmic catastrophe. Now it was possible to say that the breakaway part of our planet billions of years ago was in contact with the region of the present Kola Peninsula.

The ultra-deep well became a real triumph for Soviet science. Researchers, designers, even ordinary workers were honored and awarded for almost a whole year.

At this time, work on the Kola Superdeep was suspended. They were resumed only in September 1984. And the first launch led to the biggest accident. Employees seem to have forgotten that changes are constantly taking place inside the underground passage. The well does not forgive stopping work - and forces you to start all over again.

As a result, the drill string broke, leaving five kilometers of pipes in the depth. They tried to get them, but after a few months it became clear that this would not be possible.

Drilling work began again from the 7-kilometer mark. The depth of 12 kilometers was reached for the second time only six years later. In 1990, the maximum was reached - 12,262 meters.

And then the work of the well was affected by both failures of a local scale and events taking place in the country. The possibilities of the available technology were exhausted, state funding decreased sharply. After several serious accidents, drilling was stopped in 1992.

The scientific significance of the Kola Superdeep is difficult to overestimate. First of all, work on it confirmed the conjecture about the rich deposits of minerals at great depths. Of course, precious metals in their pure form were not found there. But at the mark of nine kilometers, layers were discovered with a gold content of 78 grams per ton (active industrial mining is carried out when this content is 34 grams per ton).

In addition, the analysis of ancient deep rocks made it possible to clarify the age of the Earth - it turned out that it is one and a half billion years older than it was commonly thought.

It was believed that there was no and could not be organic life at super-depths, but 14 previously unknown species of petrified microorganisms were found in soil samples raised to the surface, whose age was three billion years.

Shortly before closing, in 1989, the Kola Superdeep was again in the center of international attention. The director of the well, Academician David Huberman, suddenly received calls and letters from all over the world. Scientists, journalists, just inquisitive citizens were interested in the question: is it true that the super-deep well has become a "well to hell"?

It turned out that representatives of the Finnish press were talking to some employees of the Kola Superdeep. And they admitted: when the drill crossed the mark of 12 kilometers, strange noises began to be heard from the depths of the well. Instead of a drill head, the workers lowered a heat-resistant microphone - and with its help recorded sounds reminiscent of human screams. Some of the employees put forward the version that these are the cries of sinners in hell.

How true are these stories? It is technically difficult to place a microphone instead of a drill, but it is possible. True, work on its descent can take several weeks. And it would hardly have been possible to carry it out at a sensitive facility instead of drilling. But, on the other hand, many employees of the well really heard strange sounds that regularly came from the depths. And what it could be, no one knew for sure.

At the suggestion of Finnish journalists, the world press published a number of articles claiming that the Kola Superdeep is a "road to hell." Mystical significance was also attributed to the fact that the USSR collapsed when the drillers were sinking the "unfortunate" thirteenth thousand meters.

In 1995, when the station had already been mothballed, an incomprehensible explosion occurred in the depths of the mine - if only for the reason that there was nothing to explode there. Foreign newspapers reported that a demon flew out of the bowels of the Earth through a man-made passage to the surface (the publications were full of headlines like "Satan escaped from hell").

The director of the well, David Huberman, honestly admitted in an interview: he does not believe in hell and demons, but an incomprehensible explosion did take place, as well as strange noises resembling voices. Moreover, a survey conducted after the explosion showed that all the equipment was in perfect order.

For a long time, the well was considered mothballed, about 20 employees worked on it (in the 1980s, their number exceeded 500). In 2008, the facility was completely closed and part of the equipment was dismantled. The ground part of the well is a building the size of a 12-storey building, now it is abandoned and is gradually being destroyed. Sometimes tourists come here, attracted by legends about voices from hell.

According to employees of the Geological Institute of the Kola Scientific Center of the Russian Academy of Sciences, which previously managed the well, its restoration would cost 100 million rubles.

But we are no longer talking about scientific work at depth: on the basis of this object, you can only open an institute or another enterprise for training offshore drilling specialists. Or create a museum - after all, the Kola well continues to be the deepest in the world.

The deepest well in the world is located on the Kola Peninsula near the city of Zapolyarny (Murmansk region); its depth will be 12 kilometers 262 meters, which is an absolute world record. In 1997, the Kola Superdeep was listed in the Guinness Book of Records, but by that time she herself was no longer working: drilling was stopped in 1992, the well was mothballed, and what was left of the drilling rig was abandoned to the mercy of fate and actually plundered.

However, over the years of drilling, Soviet scientists managed to make many discoveries that related to the composition of the earth's crust and shed light on some scientific issues.

Preparatory work

The main task of drilling the well was to reach the Earth's mantle, which supposedly should consist of molten rocks. To do this, they decided to drill in the place of the Pecheneg trough of the Baltic Shield in the north-west of the East European Platform - one of the most ancient formations on the planet. According to scientists, the age of the rocks emerging here on the surface was at least three billion years. The main task of drilling was to identify the features of the shield and determine the boundaries between the layers of the earth's crust.

A unique team of Soviet scientists was created to create the well; up to 3,000 specialists and 16 research laboratories worked simultaneously at the well. The Soviet scientist David Mironovich Guberman became the head of the Kola Superdeep, the head of the drilling rig was Alexei Batishchev, the chief engineer was Ivan Vasilchenko, the team of geologists included famous geologists Yuri Kuznetsov, Yuri Smirnov and Vladimir Lanev.

Drilling

Throughout 1970, drilling was carried out with a conventional drilling rig, then work had to be stopped, and a new Uralmash-15000 rig, designed for deep drilling, was built at the site of the well.

This drilling rig was a tower the size of a twenty-story building, sheathed with plywood sheets on top - otherwise it was impossible to work in winter. Soviet scientists used turbine drilling, a method in which only the drill bit rotates inside the well under the pressure of the incoming fluid.

It took only about four hours a day to drill at great depths - the rest of the time was spent lifting pipes to the surface to extract cores. During this time, the drill managed to pass from seven to ten meters of rock. It took the drillers four years to cover the first seven kilometers.

The twelve-kilometer mark was already passed in 1983, after which the work was suspended - the Moscow International Geological Congress was approaching, at which the discoveries made at the well were demonstrated.

Drilling was continued in 1984, but it turned out that a deep well cannot be left unattended for a long time - changes are taking place in its structure. The accident that threw Soviet geologists to the mark of seven kilometers occurred on the very first sinking on September 27, 1984: a 200-ton column broke. Everything below seven kilometers was lost. For almost a year, geologists tried to get the pipes, but then they recognized this as impossible and began to drill a bypass shaft. The main difficulty was that from a depth of nine kilometers, core extraction became difficult - the rock crumbled and only the most durable “plaques” remained inside the pipes.

The maximum depth was reached six years later - in 1990. The pressure at this depth was 1,000 atmospheres. After that, I had to admit that the capabilities of the equipment are limited and, after several accidents, the work was curtailed.

First, it turned out that the temperature in the depths of the earth's crust is completely different from what scientists expected, who believed that it would be low to a depth of 15 kilometers. It turned out that at a depth of five kilometers it is 75 degrees Celsius, at seven it reaches 120 degrees, and at a depth of 12 kilometers it reaches 220 degrees.

Secondly, Soviet science believed that older basalts should follow younger granites. This theory has been debunked. The grant layer turned out to be several times thicker than expected, and under it lay less durable fractured rocks - Archean gneisses (Archean is a geological period that lasted from 4,000,0000 years ago to 2,500,000 years ago).

At a depth of nine to 12 kilometers, they found deep aquifers that were not expected to be found at all.

At a depth of 1.5–2 kilometers, an ore horizon was discovered - rocks rich in rare earth metals.

The olivine belt of the planet was also found, the existence of which was hypothesized at the beginning of the 20th century by the famous geologist Vladimir Afanasyevich Obruchev. It was found deeper than nine kilometers, it turned out. that it contains a concentration of gold suitable for mining.

It was discovered that rock samples at a depth of three kilometers fully correspond to the lunar soil, which confirms the theory that the Moon at one time, under the influence of an asteroid impact, could break away from the Earth.

A little bit of devilry

Superstitious people associate many legends with the Kola Superdeep. Some say that it was closed because Soviet scientists supposedly got to hell, others say that demons come out of it at night, others claim that voices of people tormented in the underworld can be heard from it.

In fact, all these are echoes of the publication of one Finnish newspaper, which just joked by releasing an article about the well on April 1st. However, as often happens, one of the American television companies picked up the joke, perhaps taking it for the truth, or perhaps deciding to scare their listeners with “terrible Russians”, after which rumors about the devilry going on in the well scattered around the world.

Of course, it was hard to work on the Kola Superdeep, the high temperature at depth and the enormous pressure created many emergencies. However, scientists assure that there was no devilry. It was difficult, often routine work.

Today, the scientific research of mankind has reached the boundaries of the solar system: we landed spacecraft on the planets, their satellites, asteroids, comets, sent missions to the Kuiper belt and crossed the border of the heliopause. With the help of telescopes, we see events that took place 13 billion years ago - when the universe was only a few hundred million years old. Against this background, it is interesting to assess how well we know our Earth. The best way to find out its internal structure is to drill a well: the deeper, the better. The deepest well on Earth is the Kola Superdeep, or SG-3. In 1990, its depth reached 12 kilometers 262 meters. If we compare this figure with the radius of our planet, it turns out that this is only 0.2 percent of the way to the center of the Earth. But even this turned out to be enough to turn the ideas about the structure of the earth's crust.

If you imagine a well as a shaft through which you can go down by elevator into the very bowels of the earth, or at least a couple of kilometers, then this is not at all the case. The diameter of the drilling tool with which the engineers created the well was only 21.4 centimeters. The upper two-kilometer section of the well is a little wider - it was expanded to 39.4 centimeters, but still there is no way for a person to get there. To imagine the proportions of the well, the best analogy would be a 57-meter sewing needle with a diameter of 1 millimeter, slightly thicker at one end.

Well scheme

But this presentation will be simplified. During drilling, several accidents occurred at the well - part of the drill string ended up underground without the possibility of extracting it. Therefore, several times the well was started anew, from the marks of seven and nine kilometers. There are four major branches and about a dozen smaller ones. The main branches have different maximum depths: two of them cross the mark of 12 kilometers, two more do not reach it by only 200-400 meters. Note that the depth of the Mariana Trench is one kilometer less - 10,994 meters relative to sea level.

Horizontal (left) and vertical projections of SG-3 trajectories

Yu.N. Yakovlev et al. / Bulletin of the Kola Scientific Center of the Russian Academy of Sciences, 2014

Moreover, it would be a mistake to perceive the well as a plumb line. Due to the fact that at different depths the rocks have different mechanical properties, the drill during the work deviated to less dense areas. Therefore, on a large scale, the profile of the Kola Superdeep looks like a slightly curved wire with several branches.

Approaching the well today, we will see only the upper part - a metal hatch screwed to the mouth with twelve massive bolts. The inscription on it was made with a mistake, the correct depth is 12,262 meters.

How was a deep well drilled?

To begin with, it should be noted that the SG-3 was originally conceived specifically for scientific purposes. The researchers chose to drill a place where ancient rocks came to the surface of the earth - up to three billion years old. One of the arguments in the exploration was that the young sedimentary rocks were well studied during oil production, and no one had yet drilled deep into the ancient layers. In addition, there were also large copper-nickel deposits, the exploration of which would be a useful addition to the scientific mission of the well.

Drilling began in 1970. The first part of the well was drilled with a Uralmash-4E serial rig - it was usually used for drilling oil wells. The modification of the installation made it possible to reach a depth of 7 kilometers 263 meters. It took four years. Then the installation was changed to "Uralmash-15000", named after the planned depth of the well - 15 kilometers. The new drilling rig was designed specifically for the Kola Superdeep: drilling at such great depths required a serious refinement of equipment and materials. For example, the weight of the drill string alone at a 15-kilometer depth reached 200 tons. The installation itself could lift loads up to 400 tons.

The drill string consists of pipes connected to each other. With its help, engineers lower the drilling tool to the bottom of the well, and it also ensures its operation. At the end of the column, special 46-meter turbodrills were installed, driven by a stream of water from the surface. They made it possible to rotate the rock crushing tool separately from the entire column.

The bits with which the drill string cut into the granite evoke associations with futuristic details from the robot - several spinning spiked disks connected to the turbine from above. One such bit was enough for only four hours of work - this roughly corresponds to a passage of 7-10 meters, after which the entire drill string must be raised, disassembled and then lowered again. Constant descents and ascents themselves took up to 8 hours.

Even the pipes for the column in the Kola Superdeep had to use unusual ones. At depth, temperature and pressure gradually increase, and, as engineers say, at temperatures above 150-160 degrees, the steel of serial pipes softens and holds multi-ton loads worse - because of this, the likelihood of dangerous deformations and breakage of the column increases. Therefore, the developers chose lighter and heat-resistant aluminum alloys. Each of the pipes had a length of about 33 meters and a diameter of about 20 centimeters - a little narrower than the well itself.

However, even specially designed materials could not withstand drilling conditions. After the first seven-kilometer section, it took almost ten years and more than 50 kilometers of pipes to further drill to the mark of 12,000 meters. Engineers were faced with the fact that below seven kilometers the rocks became less dense and fractured - viscous for the drill. In addition, the wellbore itself distorted its shape and became elliptical. As a result, the string broke several times, and, unable to lift it back, the engineers were forced to concrete the well branch and go through the wellbore again, wasting years of work.

One of these major accidents forced drillers in 1984 to concrete a well branch that reached a depth of 12,066 meters. Drilling had to be restarted from the 7-kilometer mark. This was preceded by a pause in work with the well - at that moment the existence of SG-3 was declassified, and the international geological congress Geoexpo was held in Moscow, the delegates of which visited the object.

According to eyewitnesses of the accident, after the resumption of work, the column drilled a well nine meters down. After four hours of drilling, the workers prepared to lift the column back, but it "did not go." The drillers decided that the pipe somewhere "stuck" to the walls of the well, and increased the lifting power. The workload has been drastically reduced. Gradually disassembling the string into 33-meter candles, the workers reached the next segment, ending with an uneven lower edge: the turbodrill and another five kilometers of pipes remained in the well, they could not be lifted.

The drillers managed to reach the 12-kilometer mark again only by 1990, at the same time the dive record was set - 12,262 meters. Then there was a new accident, and since 1994, work on the well was stopped.

The scientific mission of the ultra-deep

Pattern of seismic tests on SG-3

"Kola superdeep" Ministry of Geology of the USSR, publishing house "Nedra", 1984

The well was investigated by a whole range of geological and geophysical methods, ranging from core collection (a column of rocks corresponding to given depths) and ending with radiation and seismological measurements. For example, the core was taken using core receivers with special drills - they look like pipes with jagged edges. In the center of these pipes there are 6-7 centimeter holes where the rock enters.

But even with this seemingly simple (except for the need to lift this core from many kilometers deep) technique, difficulties arose. Due to the drilling fluid - the same one that set the drill in motion - the core was saturated with liquid and changed its properties. In addition, conditions in depth and on the surface of the earth are very different - the samples cracked from the pressure difference.

At different depths, the core yield was very different. If at five kilometers from a 100-meter segment it was possible to count on 30 centimeters of core, then at depths of more than nine kilometers, instead of a column of rocks, geologists received a set of washers from dense rock.

Micrograph of rocks raised from a depth of 8028 meters

"Kola superdeep" Ministry of Geology of the USSR, publishing house "Nedra", 1984

Studies of the material lifted from the well led to several important conclusions. First, the structure of the earth's crust cannot be simplified to a composition of several layers. This was previously indicated by seismological data - geophysicists saw waves that seemed to be reflected from a smooth boundary. Studies at SG-3 have shown that such visibility can also occur with a complex distribution of rocks.

This assumption affected the design of the well - scientists expected that at a depth of seven kilometers the shaft would enter basalt rocks, but they did not meet at the 12-kilometer mark either. But instead of basalt, geologists discovered rocks that had a large number of cracks and low density, which could not be expected at all from many kilometers of depth. Moreover, traces of groundwater were found in the cracks - it was even suggested that they were formed by a direct reaction of oxygen and hydrogen in the thickness of the Earth.

Among the scientific results, there were also applied ones - for example, at shallow depths, geologists found a horizon of copper-nickel ores suitable for mining. And at a depth of 9.5 kilometers, a layer of a geochemical anomaly of gold was discovered - micrometer grains of native gold were present in the rock. Concentrations reached gram per ton of rock. However, it is unlikely that mining from such a depth will ever be profitable. But the very existence and properties of the gold-bearing layer made it possible to clarify the models of the evolution of minerals - petrogenesis.

Separately, it is necessary to talk about the studies of temperature gradients and radiation. For such experiments, downhole instruments are used, which are lowered on wire-cables. The big problem was to ensure their synchronization with ground equipment, as well as to ensure operation at great depths. For example, difficulties arose with the fact that the cables, with a length of 12 kilometers, were stretched by about 20 meters, which could greatly reduce the accuracy of the data. To avoid this, geophysicists had to create new methods for marking distances.

Most commercial tools were not designed to work in the harsh conditions of the lower tiers of the well. Therefore, for research at great depths, scientists used equipment designed specifically for the Kola Superdeep.

The most important result of geothermal research is much higher temperature gradients than expected to be seen. Near the surface, the rate of temperature increase was 11 degrees per kilometer, to a depth of two kilometers - 14 degrees per kilometer. In the interval from 2.2 to 7.5 kilometers, the temperature rose at a rate approaching 24 degrees per kilometer, although existing models predicted a value one and a half times less. As a result, already at a depth of five kilometers, the instruments recorded a temperature of 70 degrees Celsius, and by 12 kilometers this value reached 220 degrees Celsius.

The Kola super-deep well turned out to be unlike other wells - for example, when analyzing the heat release of the rocks of the Ukrainian crystalline shield and Sierra Nevada batholiths, geologists showed that heat release decreases with depth. In SG-3, on the contrary, it grew. Moreover, measurements have shown that the main source of heat, providing 45-55 percent of the heat flow, is the decay of radioactive elements.

Despite the fact that the depth of the well seems colossal, it does not reach even a third of the thickness of the earth's crust in the Baltic Shield. Geologists estimate that the base of the earth's crust in this area runs about 40 kilometers underground. Therefore, even if SG-3 had reached the planned 15-kilometer cutoff, we still would not have reached the mantle.

Such an ambitious task was set by American scientists when developing the Mohol project. Geologists planned to reach the border of Mohorovichich - an underground area where there is a sharp change in the speed of propagation of sound waves. It is believed to be related to the boundary between the crust and the mantle. It is worth noting that the drillers chose the bottom of the ocean near the island of Guadalupe as a place for the well - the distance to the border was only a few kilometers. However, the depth of the ocean itself reached 3.5 kilometers here, which significantly complicated drilling work. The first tests in the 1960s allowed geologists to drill holes only 183 meters.

Plans were recently made to revive the deep ocean drilling project with the help of the exploration drilling vessel JOIDES Resolution. As a new goal, geologists have chosen a point in the Indian Ocean, not far from Africa. The depth of the Mohorovichic border there is only about 2.5 kilometers. In December 2015 - January 2016, geologists managed to drill a well with a depth of 789 meters - the fifth largest in the world of underwater wells. But this value is only half of what was required at the first stage. However, the team plans to return and complete what they started.

***

0.2 percent of the path to the center of the Earth is not such an impressive figure compared to the scale of space travel. However, it should be borne in mind that the boundary of the solar system does not pass along the orbit of Neptune (or even the Kuiper belt). The gravity of the Sun prevails over the stellar one up to distances of two light years from the star. So if you carefully calculate everything, it turns out that Voyager 2 also flew only a tenth of a percent of the path to the outskirts of our system.

Therefore, do not be upset by how little we know the "insides" of our own planet. Geologists have their own telescopes - seismic research - and their own ambitious plans to conquer the bowels. And if astronomers have already managed to touch a solid part of the celestial bodies in the solar system, then geologists have all the most interesting things yet to come.

Vladimir Korolev

Penetrating into those secrets that are under our feet is no easier than learning all the secrets of the Universe above our heads. And perhaps even more difficult, because in order to look into the depths of the Earth, a very deep well is needed.

The goals of drilling are different (oil production, for example), but ultra-deep (more than 6 km) wells are primarily needed by scientists who want to know what is interesting inside our planet. Where are such "windows" to the center of the Earth and what is the name of the deepest drilled well, we will tell you in this article. First, just one explanation.

Drilling can be done both vertically downwards and at an angle to the earth's surface. In the second case, the extent can be very large, but the depth, if measured from the mouth (the beginning of the well on the surface) to the deepest point in the bowels, is less than those that run perpendicular.

An example is one of the wells of the Chayvinskoye field, the length of which has reached 12,700 m, but in depth it is significantly inferior to the deepest wells.

This well with a depth of 7520 m is located on the territory of modern Western Ukraine. However, work on it was carried out back in the USSR in 1975-1982.

The purpose of creating this one of the deepest wells in the USSR was the extraction of minerals (oil and gas), but the study of the bowels of the earth was also an important task.

9 En-Yakhinskaya well

Not far from the city of Novy Urengoy in the Yamalo-Nenets district. The purpose of drilling the Earth was to determine the composition of the earth's crust at the drilling site and to determine the profitability of developing large depths for mining.

As is usually the case with ultra-deep wells, the subsoil presented the researchers with many "surprises". For example, at a depth of about 4 km, the temperature reached +125 (higher than the calculated one), and after another 3 km, the temperature was already +210 degrees. Nevertheless, scientists completed their research, and in 2006 the well was liquidated.

8 Saatli in Azerbaijan

In the USSR, one of the deepest wells in the world, Saatli, was drilled on the territory of the Republic of Azerbaijan. It was planned to bring its depth to 11 km and conduct various studies related to both the structure of the earth's crust and the development of oil at different depths.

Interested in

However, it was not possible to drill such a deep well, as it happens very, very often. During operation, machines often fail due to extremely high temperatures and pressures; the well is curved, since the hardness of different rocks is not uniform; often a minor breakdown entails such problems that their solution requires more funds than the creation of a new one.

So in this case, despite the fact that the materials obtained as a result of drilling were very valuable, the work had to be stopped at around 8324 m.

7 Zisterdorf - the deepest in Austria

Another deep well was drilled in Austria, near the town of Zisterdorf. There were gas and oil fields nearby, and geologists hoped that the ultra-deep well would make super-profits in the field of mining.

Indeed, natural gas was discovered at a very considerable depth - to the despair of specialists, it was impossible to extract it. Further drilling ended in an accident, the walls of the well collapsed.
It did not make sense to restore, they decided to drill another nearby, but nothing interesting for the industrialists could be found in it.

6 Universities in the USA

One of the deepest wells on Earth is the University in the USA. Its depth is 8686 m. The materials obtained as a result of drilling are of considerable interest, as they provide new material about the structure of the planet on which we live.

Surprisingly, as a result, it turned out that it was not scientists who were right, but science fiction writers: there are layers of minerals in the bowels, and life exists at great depths - however, we are talking about bacteria!

In the 1990s, drilling of the ultra-deep well Hauptborung began in Germany. It was planned to bring its depth to 12 km, but, as is usually the case with ultra-deep mines, the plans were not given success. Already at around 7 meters, problems began with the machines: drilling vertically down became impossible, the mine began to deviate more and more to the side. Each meter was given with difficulty, and the temperature grew extremely.

Finally, when the heat reached 270 degrees, and endless accidents and failures exhausted everyone, it was decided to suspend work. This happened at a depth of 9.1 km, which makes the Hauptborung well one of the deepest.

The scientific material obtained from the drilling has become the basis for thousands of studies, and the mine itself is currently used for tourism purposes.

4 Baden Unit

In the US, Lone Star attempted to drill an ultra-deep well in 1970. The location near the city of Anadarko in Oklahoma was not chosen by chance: here, wildlife and high scientific potential create a convenient opportunity for both drilling a well and studying it.

The work was carried out for more than a year, and during this time they drilled to a depth of 9159 m, which makes it possible to include it among the deepest mines in the world.

And finally, we present the three deepest wells in the world. In third place is Bertha Rogers - the world's first ultra-deep well, which, however, did not remain the deepest for long. After only a short time, the deepest well in the USSR, the Kola, appeared.

Bert Rogers was drilled by GHK, a mining company, mainly natural gas. The aim of the work was to search for gas at great depths. Work began in 1970, when very little was known about the earth's interior.

The company had high hopes for a place in Washita County, because there are many minerals in Oklahoma, and at that time scientists thought that there were entire layers of oil and gas in the thickness of the earth. However, 500 days of work and huge funds invested in the project turned out to be useless: the drill melted in a layer of liquid sulfur, and gas or oil could not be found.

In addition, scientific research was not carried out during drilling, since the well was only of commercial importance.

2 KTB-Oberpfalz

In second place in our ranking is the German well Oberpfalz, which has reached a depth of almost 10 km.

This mine holds the record as the deepest vertical well, since it goes to a depth of 7500 m without deviation to the side! This is an unprecedented figure, because the mines at great depths inevitably bend, but the unique equipment used by scientists from Germany made it possible to move the drill vertically down for a very long time.

Not so big and the difference in diameter. Ultra-deep wells begin on the surface of the earth with a hole of a rather large diameter (at Oberpfalz - 71 cm), and then gradually narrow. At the bottom, the German well has a diameter of only about 16 cm.

The reason why the work had to be stopped is the same as in all other cases - equipment failure due to high temperatures.

1 Kola well - the deepest in the world

We owe a stupid legend to the “duck” launched in the Western press, where, with reference to the mythical “scientist of world renown” Azzakov, it was told about a “creature” that escaped from a mine, the temperature in which reached 1000 degrees, about the groans of millions of people who signed up for microphone down and so on.

At first glance, it is clear that the story is sewn with white thread (and it was published, by the way, on April Fool's Day): the temperature in the mine was no higher than 220 degrees, however, with it, as well as at 1000 degrees, no microphone can work ; creatures did not break out, and the named scientist does not exist.

The Kola well is the deepest in the world. Its depth reaches 12262 m, which significantly exceeds the depth of other mines. But not length! At least three wells can now be named - Qatar, Sakhalin-1 and one of the wells of the Chayvo field (Z-42) - which are longer, but not deeper.
Kolskaya gave scientists colossal material, which has not yet been fully processed and comprehended.

Place	Name	The country	Depth
1	Kola	the USSR	12262
2	KTB-Oberpfalz	Germany	9900
3	USA	9583
4	baden unit	USA	9159
5	Germany	9100
6	USA	8686
7	Zisterdorf	Austria	8553
8	USSR (modern Azerbaijan)	8324
9	Russia	8250
10	Shevchenkovskaya	USSR (Ukraine)	7520

In the USSR, they loved the scale, but more, and this applied to literally everything. So one well was dug in the Union, which today bears the title of the deepest on earth. It is noteworthy that the well was not drilled for oil production or geological exploration, but purely for scientific research.

Tips used to drill a well.

The Kola super-deep well, or SG-3, is the deepest well in the earth made by man. It is located in the Murmansk region, 10 kilometers from the city of Zapolyarny, in a western direction. The depth of the hole is 12,262 meters. Its diameter at the top is 92 centimeters. At the bottom - 21.5 centimeters. An important feature of the SG-3 is that, unlike any other wells for oil production or geological work, this one was drilled exclusively for scientific purposes.

The well was laid in 1970, on the occasion of the 100th anniversary of the birth of Vladimir Lenin. The chosen location is remarkable in that the well was drilled in outcropping volcanic rocks over 3 billion years old. By the way, the age of the Earth is about 4.5 billion years. When mining, wells are rarely drilled deeper than two thousand meters.

The work went on for days on end.

Drilling began on May 24, 1970. Up to the mark of 7,000 meters, drilling proceeded easily and calmly, but after the head hit the less dense rocks, problems began. The process has slowed down considerably. Only on June 6, 1979 a new record was set - 9583 meters. It was previously installed in the US by oil producers. The mark of 12,066 meters was passed in 1983. The result was achieved by the International Geological Congress, which was held in Moscow. Subsequently, two accidents occurred at the complex.

Now the complex looks like this.

In 1997, several legends were circulated in the media at once that the Kola super-deep well was the real road to hell. One of these legends said that when the team lowered the microphone to a depth of several thousand meters, human screams, groans and screams were heard there.

Of course, there was nothing of the kind. If only because special equipment is used to record sound in a well at such a depth - but it did not record anything either. There were indeed several accidents at the complex, including an underground explosion during drilling, but geologists definitely did not disturb any underground “demons”.

The well itself is mothballed.

It is really important that 16 research laboratories worked at SG-3. During the Soviet Union, domestic geologists were able to make many valuable discoveries and better understand how our planet works. The work at the site allowed to significantly improve the drilling technology. The scientists were also able to understand the local geological processes, received comprehensive data on the thermal regime of the bowels, underground gases and deep waters.

Unfortunately, today the Kola super-deep well is closed. The building of the complex has been deteriorating since the last laboratory was closed here in 2008, and all equipment was dismantled. The reason is simple - lack of funding. In 2010, the well was already mothballed. Now it is slowly but surely destroyed under the influence of natural processes.