Voices from a well on the Kola Peninsula. The legendary Kola superdeep

The world's deepest well (the Kola superdeep well) was not created to find oil.

The width of this well is only 23 centimeters, but the depth is 12,226 meters, which makes its base the deepest point on Earth that man has ever reached. And it appeared thanks to a duel between scientists. American and Soviet researchers tried to outdo each other in everything.

Everyone knows the space race: the Soviet Union was the first to send humans into space, but the Americans were the first to land on the moon.

But few people know that a similar race took place in the underground space: in 1958, the Americans founded their “Mohole Project” off the Pacific coast of Mexico, which they stopped funding and it closed in 1966, while the Russians drilled from 1970 to the beginning of 1990. x years.

The result was the Kola superdeep well, which is a system of several wells extending from the main hole. The deepest well is called SG-3, and it goes an impressive distance inside the crust of the Kola Peninsula.

If you have a hard time imagining how deep this hole is, that's okay. You could say that it is almost 38 Eiffel Towers deep. Well, or it is the same length as a chain of 13,000 adult badgers walking head to tail.

As one would expect, thanks to SG-3, a lot of unique geological data was obtained, but what paleontologists found there took everyone by surprise. The Smithsonian Institution says that, despite quite extreme conditions environment, at a depth of about 6.5 kilometers, almost intact plankton fossils dating back 2 billion years were found.

It was also discovered that much of the seismic data - at the depths where granite turns into basalt - was misunderstood by scientists, and what was previously thought to be an unknown geological layer was merely slow changes in temperature and density.

Scientists also see freely flowing water there, which, due to enormous pressure, was squeezed out of the stones.

Such drilling projects (like the Mohole project and several other more recent ones) are most often abandoned due to lack of funding. Work on the Kola well stopped when it turned out that the temperature at such a depth was about 180⁰С, and not 100 degrees, as expected.

In general, drilling more than 12 kilometers seems like an incredible technical feat, and it is, but this entire well is nothing more than a small prick of the Earth's surface. The equatorial radius of the Earth is 6,378 kilometers, and such an impressive borehole passed only 0.19 percent of the way to the center of the planet.

So can a person go even deeper? Is it ever possible to reach the red-hot mantle? It depends on where you will be drilling.

The thickness of the oceanic crust is, on average, about 7 kilometers. The continental crust is somewhat less dense, but much thicker - on average about 35 kilometers. At these depths, the temperature and pressure are too high for any mechanism, so why not drill in the ocean?

And such attempts are being made. For example, a group of scientists is trying to drill into a relatively cold area earth's crust on the Atlantic Spit in the Indian Ocean.

The fact that this area is very dense and underwater presents significant challenges for engineers, which is why the project has been put on hold for the past few years. But this still won't stop scientists from trying to get to the primordial, slowly seething inner mantle.

Today there is no drilling on the Kola superdeep; it was stopped in 1992. SG was not the first and not the only one in the program for studying the deep structure of the Earth.

Three of the foreign wells reached a depth of 9.1 to 9.6 km. It was planned that one of them (in Germany) would surpass the Kola one. However, drilling at all three, as well as at SG, was stopped due to accidents and for technical reasons cannot yet be continued.

Apparently, it is not for nothing that the complexity of drilling ultra-deep wells is compared with a flight into space, with a long space expedition to another planet. Rock samples extracted from the earth's interior are no less interesting than samples of lunar soil.

The soil delivered by the Soviet lunar rover was studied at various institutes, including the Kola Science Center. It turned out that the composition of the lunar soil almost completely corresponds to the rocks extracted from the Kola well from a depth of about 3 km.

The well showed that almost all of our previous knowledge about the structure of the earth's crust is incorrect. It turned out that the Earth is not at all like a layer cake. “Up to 4 kilometers everything went according to theory, and then the end of the world began,” says Huberman.

Theorists promised that the temperature of the Baltic Shield would remain relatively low to a depth of at least 15 kilometers. Accordingly, it will be possible to dig a well up to almost 20 kilometers, just up to the mantle.

But already at 5 kilometers the ambient temperature exceeded 70 degrees Celsius, at seven - over 120 degrees, and at a depth of 12 it was hotter than 220 degrees - 100 degrees higher than predicted. Kola drillers questioned the theory of the layered structure of the earth's crust - at least in the interval up to 12,262 meters.

At school we were taught: there are young rocks, granites, basalts, mantle and core. But the granites turned out to be 3 kilometers lower than expected. Next there should have been basalts. They weren't found at all. All drilling took place in the granite layer. This is a very important discovery, because all our ideas about the origin and distribution of minerals are connected with the theory of the layered structure of the Earth.

The objectives set in the ultra-deep drilling project have been completed. Special equipment and technology for ultra-deep drilling, as well as for studying wells drilled to great depths, have been developed and created. We received information, one might say, “first hand” about physical condition, properties and composition rocks in their natural occurrence and on core to a depth of 12,262 m.

The well gave an excellent gift to the homeland at shallow depths - in the range of 1.6-1.8 km. Industrial copper-nickel ores were opened there - a new ore horizon was discovered. And it comes in handy, because the local nickel plant is already running short of ore.

As noted above, the geological forecast of the well section did not come true. The picture that was expected during the first 5 km in the well extended for 7 km, and then completely unexpected rocks appeared. The basalts predicted at a depth of 7 km were not found, even when they dropped to 12 km.

It was expected that the boundary that gives the greatest reflection during seismic sounding is the level where the granites transform into a more durable basalt layer. In reality, it turned out that less strong and less dense fractured rocks are located there - Archean gneisses. This was never expected. And this is fundamentally new geological and geophysical information, which allows us to interpret the data of deep geophysical research differently.

The data on the process of ore formation in the deep layers of the earth’s crust also turned out to be unexpected and fundamentally new. Thus, at depths of 9-12 km, highly porous fractured rocks were encountered, saturated with highly mineralized underground waters. These waters are one of the sources of ore formation. Previously, it was believed that this was possible only at much shallower depths.

It was in this interval that an increased gold content was found in the core - up to 1 g per 1 ton of rock (a concentration considered suitable for industrial development). But will it ever be profitable to mine gold from such depths?

Ideas about thermal mode of the earth's interior, about the deep distribution of temperatures in areas of basalt shields. At a depth of more than 6 km, a temperature gradient of 20°C per 1 km was obtained instead of the expected (as in the upper part) 16°C per 1 km. It was revealed that half of the heat flow is of radiogenic origin.

Having drilled the unique Kola superdeep well, we learned a lot and at the same time realized how little we still know about the structure of our planet.

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Despite the fact that it is the 21st century, internal structure Very little has been studied of our planet. We know quite well what is going on in deep space, but at the same time, the degree of penetration into the secrets of the Earth can be compared to a light pinprick into the surface of the rind of a watermelon.
In the mid-1950s, when drillers learned to make wells more than 7 km deep, humanity came closer to achieving a very ambitious task - to go through the earth's crust and see what lies beneath it. Our compatriots came closest to this goal when they drilled the Kola superdeep well.
The Earth's solid shell is surprisingly thin relative to its size - the thickness of the crust varies between 20-65 km on land and 3-8 km under the ocean, occupying less than 1% of the planet's volume. Behind it is a vast layer - the mantle - which accounts for the bulk of the Earth's volume. Even lower is the dense core, consisting primarily of iron, but also nickel, lead, uranium and other metals. Between the crust and the mantle there is a boundary zone, named after the Yugoslav scientist who discovered it, the Mohorovic surface (border), or Moho for short. In this zone, the speed of propagation of seismic waves increases sharply. There are a number of hypotheses designed to explain this phenomenon, but in general it remains unsolved.

The most important goal of the most serious deep drilling projects launched in the second half of the 20th century was precisely this mysterious layer. Researchers were never able to reach it, but the data on the structure of the earth’s crust obtained during the drilling of ultra-deep wells turned out to be so unexpected that the Mohorovic boundary seemed to fade into the background. First it was necessary to explain the mysteries discovered in higher layers.
The Americans were the first to begin deep drilling of the earth's crust for scientific purposes. In the 1960s, they launched the Mohole scientific project, which involved the creation of underwater ones using special drilling ships. Over the next thirty years, more than 800 wells appeared in the seas and oceans, many of which are located at depths of more than 4 km. The longest well was able to go only 800 m into the seabed, and yet the data obtained were of enormous importance for geology. In particular, they served as significant confirmation of the so-called. tectonic theory, according to which the continents are based on solid lithospheric plates, slowly floating, immersed in a liquid mantle.

Of course, the USSR could not lag behind its overseas competitor, so in the mid-1960s, we launched numerous projects to study the earth’s crust. Soviet scientists took a slightly different path, deciding to drill wells not in the sea, but on land. The most famous and successful project of this kind is the Kola superdeep well - the deepest “hole in the ground” ever made by man. The well is located at the northern tip of the Kola Peninsula. This place was not chosen by chance - over hundreds of millions of years, natural erosion destroyed the surface of the Kola crystalline shield, stripping off its upper layers of rock. As a result, ancient Archean layers appeared on the surface, corresponding to depths of 5-10 km for an average section of the earth’s crust continental type. The 15-kilometer design depth of the well allowed scientists to hope to reach the mysterious Mohorovic surface.
Drilling of the Kola well began in 1970, and it ended more than 20 years later - in 1994. At first, the drillers worked using completely traditional methods: a column of light-alloy pipes was lowered into the well, at the end of which a cylindrical metal drill with diamond teeth and sensors was attached. The column was rotated by an engine located on the surface. As the depth of the well increased, new sections were added to the pipes. Periodically, the entire column had to be lifted to the surface to remove the cut rock core and replace the dull crown. Unfortunately, this proven technology becomes ineffective when the well depth exceeds a certain mark: the friction of the pipes against the walls of the well becomes too great for this entire huge shaft to be rotated. To overcome this difficulty, engineers developed a design in which only the drill head rotated. Turbines were installed at the end of the column, through which drilling fluid was passed - a special liquid that acts as a lubricant and circulates through the pipes. These turbines made the drill rotate.

The samples brought to the surface during the drilling process made a real revolution in geology. Existing ideas about the structure of the earth's crust turned out to be far from reality. The first surprise was the absence of a transition from granite to basalt, which scientists expected to see at a depth of about 6 km. Seismological studies indicate that in this area the speed of propagation of acoustic waves changes sharply, which has been interpreted as the beginning of a basaltic foundation of the earth's crust. However, even after the transition zone, granites and gneisses continued to rise to the surface. From this point on, it became clear that the prevailing model of a two-layer earth's crust was incorrect. Now the presence of a seismic transition is explained by a change in the properties of the rock under conditions of increased pressure and temperature.
An even more surprising discovery was the fact that rocks located at depths of more than 9 km turned out to be extremely porous. Before this, it was believed that as depth and pressure increase, they, on the contrary, should become increasingly dense. The miniature cracks were filled with an aqueous solution whose origin for a long time remained completely unclear. Later, a theory was put forward according to which the discovered water is formed from hydrogen and oxygen atoms, which are “squeezed out” from the surrounding rock under the influence of colossal pressures.
Another surprise: life on planet Earth turns out to have arisen 1.5 billion years earlier than expected. At a depth of 6.7 km, where it was believed that there was no organic matter, 14 species of fossilized microorganisms were discovered. They were found in extremely uncharacteristic carbon-nitrogen deposits (instead of the usual limestone or silica) that were over 2.8 billion years old. At even greater depths, where there are no longer sediments, methane appeared in huge concentrations. This completely and utterly destroyed the theory. biological origin hydrocarbons such as oil and gas.
Scientists were also extremely surprised by the speed with which the temperature increased as the well deepened. At the 7 km mark it reached 120 °C, and at a depth of 12 km it was already 230 °C, which was a third higher than the planned value: the temperature gradient of the crust was almost 20 degrees per 1 km, instead of the expected 16. It was also found that half of the heat flow is of radiogenic origin. High temperature negatively affected the operation of the bit, so the drilling fluid began to be cooled before pumping into the well. This measure turned out to be quite effective, however, after passing the 12 km mark, it was no longer able to provide sufficient heat removal. In addition, the compressed and heated rock acquired some properties of a liquid, as a result of which the well began to float the next time the drill string was removed. Further progress turned out to be impossible without new technological solutions and significant cash costs, so in 1994 drilling was suspended. By that time, the well had deepened to 12,262 m.

In the 50-70s of the last century, the world changed at incredible speed. Things have appeared that are difficult to imagine today’s world without: the Internet, computers, cellular communications, space exploration and depths of the sea. Man was rapidly expanding the spheres of his presence in the Universe, but he still had rather rough ideas about the structure of his “home” - planet Earth. Although even then the idea of ​​ultra-deep drilling was not new: back in 1958, the Americans launched the Mohole project. Its name is formed from two words:

Moho- a surface named after Andrija Mohorovicic, a Croatian geophysicist and seismologist who in 1909 identified the lower boundary of the earth’s crust, on which there is an abrupt increase in the speed of seismic waves;
Hole- well, hole, opening. Based on assumptions that the thickness of the earth's crust under the oceans is much less than on land, 5 wells were drilled near the island of Guadelupe with a depth of about 180 meters (with an ocean depth of up to 3.5 km). Over five years, researchers drilled five wells, collected many samples from the basalt layer, but did not reach the mantle. As a result, the project was declared a failure and the work was stopped.

The Kola superdeep well is the deepest borehole in the world. Located in Murmansk region, 10 kilometers west of the city of Zapolyarny, on the territory of the geological Baltic shield. Its depth is 12,262 meters. Unlike other ultra-deep wells that were made for oil production or geological exploration, SG-3 was drilled solely to study the lithosphere in the place where the Mohorovicic boundary comes close to the Earth's surface.

The Kola superdeep well was laid in honor of the 100th anniversary of Lenin’s birth, in 1970.
Sedimentary rock strata by that time had been well studied during oil production. It was more interesting to drill where volcanic rocks about 3 billion years old (for comparison: the age of the Earth is estimated at 4.5 billion years) come to the surface. For mining, such rocks are rarely drilled deeper than 1-2 km. It was assumed that already at a depth of 5 km the granite layer would be replaced by basalt.

On June 6, 1979, the well broke the record of 9,583 meters previously held by the Bertha Rogers well (an oil well in Oklahoma). IN best years on Kola ultra-deep well There were 16 research laboratories, they were personally supervised by the Minister of Geology of the USSR.

What happens in the depths is not known for certain. Ambient temperature, noise and other parameters are transmitted upward with a minute delay. However, drillers say that even such contact with the underground can be seriously frightening. The sounds coming from below really look like screams and howls. To this we can add a long list of accidents that plagued the Kola Superdeep when it reached a depth of 10 kilometers.

Twice the drill was taken out melted, although the temperatures at which it can melt are comparable to the temperature of the surface of the Sun. One day, it was as if the cable had been pulled from below and was torn off. Subsequently, when they drilled in the same place, no remains of the cable were found. What caused these and many other accidents still remains a mystery. However, they were not the reason for stopping drilling in the Baltic Shield.

Excavation of the core to the surface.

Extracted core.

Although it was expected that a clear boundary between granites and basalts would be discovered, only granites were found in the core throughout the depth. However, due to high pressure compressed granites greatly changed their physical and acoustic properties.
As a rule, the lifted core crumbled due to active gas release into sludge, since it could not withstand a sharp change in pressure. It was possible to remove a strong piece of core only with a very slow lifting of the drill, when the “excess” gas, still pressed to high pressure, had time to escape from the rock.
Density of cracks on great depth, contrary to expectations, increased. There was also water at depth that filled the cracks.

Tricone chisel.

Eruptive basalt breccia from a depth of 2977.8 m

“We have the deepest hole in the world - so we must use it!” – David Guberman, the permanent director of the Kola Superdeep Research and Production Center, exclaims bitterly. In the first 30 years of the Kola Superdeep, Soviet and then Russian scientists broke through to a depth of 12,262 meters. But since 1995, drilling has been stopped: there was no one to finance the project. What is allocated within the framework of UNESCO's scientific programs is only enough to maintain the drilling station in working condition and study previously extracted rock samples.

Huberman recalls with regret how many scientific discoveries took place on the Kola Superdeep. Literally every meter was a revelation. The well showed that almost all of our previous knowledge about the structure of the earth's crust is incorrect. It turned out that the Earth is not at all like a layer cake. “Up to 4 kilometers everything went according to theory, and then the end of the world began,” says Huberman. Theorists promised that the temperature of the Baltic Shield would remain relatively low to a depth of at least 15 kilometers. Accordingly, it will be possible to dig a well up to almost 20 kilometers, just up to the mantle.

But already at 5 kilometers the ambient temperature exceeded 70 degrees Celsius, at seven - over 120 degrees, and at a depth of 12 it was hotter than 220 degrees - 100 degrees higher than predicted. Kola drillers questioned the theory of the layered structure of the earth's crust - at least in the interval up to 12,262 meters.

Another surprise: life on planet Earth turns out to have arisen 1.5 billion years earlier than expected. At depths where it was believed that there was no organic matter, 14 species of fossilized microorganisms were discovered - the age of the deep layers exceeded 2.8 billion years. At even greater depths, where there are no longer sediments, methane appeared in huge concentrations. This completely and utterly destroyed the theory of the biological origin of hydrocarbons such as oil and gas.

There were almost fantastic sensations. When in the late 70s the Soviet automatic space station brought 124 grams of lunar soil to Earth, Kola researchers scientific center They found that it is exactly like samples from a depth of 3 kilometers. And a hypothesis arose: the Moon broke away from the Kola Peninsula. Now they are looking for where exactly. By the way, the Americans, who brought half a ton of soil from the Moon, did nothing meaningful with it. They were placed in airtight containers and left for research by future generations.

The history of the Kola Superdeep is not without mysticism. Officially, as already mentioned, the well stopped due to lack of funds. Coincidence or not, it was precisely in 1995 that a powerful explosion of unknown origin was heard in the depths of the mine.

"When I talk about this mysterious story They started asking questions at UNESCO, I didn’t know what to answer. On the one hand, it's bullshit. On the other hand, I, as an honest scientist, could not say that I know what exactly happened to us. A very strange noise was recorded, then there was an explosion... A few days later, nothing like that was found at the same depth,” recalls academician David Guberman.

Quite unexpectedly for everyone, Alexei Tolstoy’s predictions from the novel “Engineer Garin’s Hyperboloid” were confirmed. At a depth of over 9.5 kilometers, a real treasure trove of all kinds of minerals, in particular gold, was discovered. A real olivine layer, brilliantly predicted by the writer. It contains 78 grams of gold per ton. By the way, industrial production possible at a concentration of 34 grams per ton. Perhaps in the near future humanity will be able to take advantage of this wealth.

This is what the Kola Superdeep looks like now, it’s in a deplorable state.

Back in 1990, in the southern part of Germany, a group of scientists decided to look into the depths of our planet at the junction of two tectonic plates that collided more than 300 million years ago, when the continent was formed. The final goal of the scientists was to drill one of the deepest wells in the world, up to 10 km.

Initially, it was assumed that the well would become a kind of “telescope”, which would make it possible to learn more about the depths of our planet and try to learn about the Earth’s core. The drilling process took place as part of the Continental Deep Drilling program and lasted until October 1994, when the program had to be curtailed due to financial problems.

The well was named Kontinentales Tiefbohrprogramm der Bundesrepublik, abbreviated KTB, and by the time the program was closed it had been drilled to more than 9 km, which did not add enthusiasm to the scientists. The drilling process itself was not easy. Over the course of 4 years, scientists, engineers and workers had to deal with a whole heap of difficult situations and quite complex tasks. For example, the drill had to pass through rocks heated to a temperature of about 300 degrees Celsius, but even under such conditions, the drillers still managed to cool the hole with liquid hydrogen.

However, despite the fact that the program was curtailed, scientific experiments did not stop and carried them out until the end of 1995 and it is worth noting that they were carried out not in vain. During this time, we managed to discover new, quite unexpected facts structure of our planet, new maps of temperature distribution were compiled and data on the distribution of seismic pressure were obtained, which made it possible to create models of the layered structure of the upper part of the Earth's surface.

However, scientists saved the most interesting for last. Dutch scientist Lott Given, who, together with acoustic engineers and scientists from the Geophysical Research Center (Germany), did what many had dreamed of - almost in the literal sense of the word, he “heard the heartbeat” of the Earth. To do this, he and his team needed to carry out acoustic measurements, with the help of which research group recreated the sounds that we could hear at a depth of 9 kilometers. However, now you can hear these sounds too.

Despite the fact that KTB is on at the moment Considered the deepest well in the world, there are several similar wells, which, however, have already been sealed. And among them, a well stands out, which during its existence has managed to acquire legends; this is the Kola super-deep well-well, better known as the “Road to Hell”. Unlike other competitors of KTB, Kola well reached 12.2 km in depth and was considered the deepest well in the world.

Its drilling began in 1970 in the Murmansk region ( Soviet Union, now Russian Federation), 10 kilometers west of the city of Zapolyarny. During drilling, the well experienced several accidents, as a result of which workers had to concrete the well and start drilling from a much shallower depth and at a different angle. It is interesting that it is with a series of accidents and failures that haunt the group that the reason for the emergence of the legend that the well was drilled all the way to the real Hell is associated.

As the text of the legend says, after passing the 12 km mark, scientists were able to hear the sounds of screams using microphones. However, they decided to continue drilling and while passing the next mark (14 km), they suddenly came across voids. After the scientists lowered the microphones, they heard the screams and moans of men and women. And after some time, an accident occurred, after which it was decided to stop drilling work

And, despite the fact that the accident really happened, scientists did not hear any screams of people, and all the talk about demons was nothing more than fiction, said David Mironovich Guberman, one of the authors of the project, under whose leadership the well was drilled.

After another accident in 1990, upon reaching a depth of 12,262 meters, drilling was completed, and in 2008, the project was abandoned and the equipment was dismantled. Two years later, in 2010, the well was mothballed.

Let us note that projects such as drilling wells such as the KTV and Kola wells are currently the only way and opportunity for geologists to study the interior of the planet.