The well -threatened oil well in the world exposed: the unexpected finding that caused its sudden closure

In the most northern European Russia, where the soil remains frozen during most of the year and the silence of the tundra is barely interrupted by the creak of the Arctic winds, a milestone of Soviet science awaits in the stillness: Kola’s superprofundo well. A work of this caliber and cost should have an important economic return, but no. The well was not conceived to extract the valuable oil that abounds in Russia, but to enter the bowels of the earth itself. This vertical colossus, with its 12,262 meters deep (the second deepest well has ended a few weeks ago in China), it continues to be the deepest hole ever perforated by the human being. What began as a symbol of scientific supremacy of the Soviet block during the Cold War, ended up becoming a geological odyssey that challenged the technical, physical and financial limits of the twentieth century.

The project, baptized as SG-3, was officially initiated on May 24, 1970, in the Pechenga region, in the Kola Peninsula, just ten kilometers from the city of Zapolyarny. Its purpose was to explore the deep structures of the continental cortex of the Baltic shield, with the hope of reaching, and finally crossing, the hypothetical border between the earth’s cortex and the mantle: the discontinuity of Mohorovicic.

To do this, pioneer technologies were developed, such as drills with background hydraulic engines, aluminum light alloy tools to support their own weight to such depths, and hydraulic transport systems of rock witnesses. The well, completely drilled in precambrian crystalline rocks, was an unprecedented company. As the geologist Konstantin V. Lobanov, Co -author of the Commemorative Study of the 50 years of the projecteither, “The SG-3 is an achievement comparable to spatial flights, but directed towards the interior of the earth“

The big temperature problem

However, this ambitious descent towards the unknown stumbled upon an invisible but implacable enemy: heat. As drilling exceeded 7,000 meters and entered the archaic gneises of more than 2.5 billion years, temperatures began to rise above the expected. At 10 kilometers deep, 180 ° C were recorded, and the 12 kilometers, 212 ° C were reachedaccording to Jorge Navarro, professor of the Master of Petroleum and Gas Engineering at the Polytechnic University of Madrid, in statements to Electomista.es.

The teams, Designed to withstand up to 100–120 ° Cthey began to fail, and the materials were easily deformed. The earth’s crust, far from being a passive medium, rebelled with pressure, heat and unforeseen fractures. “The temperature increase in SG-3 was significantly higher than expected, which raises important challenges for the extrapolation of in-depth geophysical data,” conclude the authors of the Russian study.

Despite difficulties, perforation provided immense scientific wealth. Witnesses of great value were extracted, revealing complex structures, un-metamorphic shear areas, and Up to six different types of mineralization, including unexpected gold and silver veins more than 9,000 meters deep. It was also discovered that the supposed “border of the basement”, that border between granite and basaltic rocks inferred by the seismic data, did not exist as thought. The densely compacted granitoids were responsible for seismic reflections, which forced consolidated theories about the composition of the earth’s cortex. “The idea of ​​a basaltic layer was replaced by the existence of a ‘cortical wave guide’ formed by fractured and broken rocks,” says Nikolay V. Sharov, work co -author.

Accident after accident

Over the years, the well suffered numerous accidents. In 1984, a section of the Drilling pipe was stuck at more than 12 kilometers deep. 5 kilometers of pipe were lost. Restart the work required to pierce this section with a new branch, which extended the operation for years. In fact, more than a dozen branches were drilled from the main well, creating a kind of ‘multilateral wells’ under the cortex. While the engineers struggled to advance just a few meters a month, geologists celebrated the opportunity to access an unprecedented three -dimensional vision of the Baltic Shield, formed at the dawn of the planet.

In 1990, The SG-3 reached its maximum depth: 12,262 meters. There were only three kilometers to reach the initial objective of 15 kilometers, but the technical and economic conditions were already unsustainable. A layer formed by extremely dense rocks had been reached that greatly hindered operations, along with temperatures that no one had planned. In 1992 the operation was officially arrested and in 1995 the scientific research ceased. A decade later, in 2007, the Uralmash-15000 drilling equipment was completely dismantled. Thus he closed, in silence and without a ceremony, one of the most daring scientific experiments of the twentieth century.

The vestiges of the place from where SG-3 was drilled, today sealed and covered with snow during much of the year, are still standing as a monument to the human will to explore the limits of knowledge. The well found no oil, nor reached the land mantle, but what he offered was even more valuable: A rereading of the land subsoil, new theories on the formation of mineral deposits and a silent revolution in the way of understanding deep geology. As the Soviet geophysicist Andrei Laverov wrote: “With SG-3, we did not go down, but inside. Towards the bowels of our own geological past.”

At half a century at the beginning of his excavation, Kola’s well has not been overcome in depth. It is still a closed window to the abyss, a vestige of the Soviet ambition, and at the same time, a scientific lighthouse that illuminated what until then was only speculation. In a world that looks more and more towards space, the SG-3 reminds us that there are still many secrets under our feet, waiting to be discovered.