Why drill wells today? The closest and most familiar example: to ensure water supply. As a rule, such a water well is shallow, and it stops growing as soon as the aquifer is reached. Another example that everyone is hearing: wells for hydrocarbon production, an integral part of oil and gas fields. The fact that it is possible to drill the earth’s crust for many kilometers for the sake of science, and not “black gold”, is almost forgotten.
More than forty years have passed since the day when the deepest well in the history of drilling operations was laid on the
Kola Peninsula, under the city of Zapolyarny in the Murmansk Region. Its goal was “pure” science - it was to study the lithosphere in a place where, at great depths, scientists expected to get a lot of interesting information. The age of the studied rocks was estimated at 3 billion years - at this time the Earth was still very young.
The first years of drilling did not differ much from ordinary operations in the exploration of oil and gas deposits. Even the equipment was used familiar, serial. Below 2 thousand meters, the drill string began to be equipped with pipes, the manufacture of which used
aluminum alloys - a multi-kilometer steel string would simply not have supported its own weight. The maximum achieved weight of the drill string is about 200 tons.
Even before reaching the 7-kilometer mark, the Kola superdeep began to present real puzzles to scientists. The drill drilled only granite of different densities, which did not even think of giving way to basalt. At a depth of one and a half kilometers, deposits of
copper ore were found
. After another 1.5 kilometers, the composition of the elevated rock sample turned out to be very similar to the soil samples delivered by the Soviet stations from the Moon. The temperature grew much faster than in theoretical calculations. And the organic fossils found in the sample from a depth of 6.7 km made scientists question the old dates of life on Earth.
Upon reaching a depth of 7 thousand meters, the deepest well required the most modern methods at that time. By this time, drilling was sharply complicated due to the passage of layered rocks with less strength. The drilling cycle took a whole day, of which only 4 hours for actual drilling, the rest of the time the drill string was slowly rising to replace the
drill bit that had become unusable during these hours
. If it was wedged by the rock that had crumbled inside the wellbore, part of the column was broken off when trying to rise. She had to cement and continue drilling with a deviation of the tool, on a new branch.
Since 1979, the Kola Superdeep has received the official status of
"the deepest well in the world." In 1983, the drillers took the 12-kilometer line. The following year, due to a break in the column, I had to start again from 7 kilometers. In 1990, the Guinness Book of Records recorded a record achieved on a new branch. It was 12.262 meters. And the first break in the column after that put an end to the project.
They were waiting for a new, more advanced technique, but it never appeared. The funding has run out. The state was not interested in continuing the "journey to the center of the earth." In 2008, the deepest well lost equipment dismantled from it. Now it is abandoned, and its structures are slowly being destroyed. Experts say that it is possible to restore the Kola superdeep, you just need to find tens of millions of rubles somewhere ...