Kola Superdeep Borehole: The Deepest Hole Ever Drilled

The Soviet Union's Kola Superdeep borehole is a testament to extreme engineering. It plunges 12,262 meters, seven and a half miles, nine inches wide but over 12 kilometers deep. This feat, part of the Cold War space race, was the world’s greatest engineering effort before the International Space Station.

The Kola Superdeep Borehole

The Kola borehole was an ambitious experiment. It started in the name of national pride in 1970, during the Cold War, as the Soviet Union and the United States raced to drill the deepest hole in the Earth. Located in the frozen north of Russia, near the Barents Sea, the borehole’s scale is breathtaking. Drilling was a feat of engineering. It required drilling through layers of rock, granite, and basalt over 19 years at a constant 9-inch diameter, tracing the center of the Earth. Equipment that generated such a minimal diameter over such a colossal distance is impressive. It would be the deepest man-made point in the planet’s crust—until it stopped. What made them stop became an enduring mystery.

The race against America

During the Cold War, many extraordinary projects competed for national prestige. The Kola project was part of this competition to pierce as far into the planet as possible, showcasing technological prowess. Made in response to the United States's 1961 moon shot, this was a case where American and Soviet scientists raced to gain knowledge about the Earth. The Soviet Union’s project was scaled by the scientific community to explore the Earth’s crust.

The success of the Kola Superdeep

The Kola borehole started as a project by the Soviet Union to drill as deep into the Earth as possible. This colossal project aimed to test the Earth's crust and mantle's composition and temperature.

The unexpected findings

At 12,262 meters below the earth’s surface, the core temperature climbed over 350 degrees. The rock heated to such an extent that it began to flow like plastic, preventing the drilling process from going any deeper. The temperatures were far hotter than expected, creating a new problem to solve. The temperature, however, wasn't the only puzzling thing.

The eerie rumors

The high temperatures and extreme conditions led to a rumor that the boils were from hell itself, with screams recorded from the depths. The truth, however, was more mundane. The explorers found traces of water and microscopic fossils much deeper than where they should exist. The specialists made these discoveries at a depth of 6 kilometers, inside the temperatures extending over 35,000°C. The scientists also noticed that the rock changed its physical properties at this depth, possibly changing the Earths mantle and crust. This was a surprise for everyone involved.

What made them stop?

It wasn't the hellish temperature and the rock that softened that ended the project. The problem was the rock itself. As the borehole went deeper, the rock became softer. The Earth’s crust was much more complicated. The rocks that were once solid and hard suddenly began to change their physical properties and started flowing like plastic. The Kola Superdeep Borehole was an ambitious geophysical experiment that involved drilling as deep as possible into the Earth's crust to understand its composition. The project was part of a Cold War-era competition with the United States to achieve engineering feats, showcasing Soviet technological prowess. It began in 1970 and resulted in a hole 12,262 meters (over 7.5 miles) deep and approximately 9 inches (23 centimeters) wide. The drilling process required cutting through layers of rock, granite, and basalt, taking 19 years to complete. The project faced numerous challenges, including extreme temperatures and unexpected geological conditions, which ultimately led to its abandonment in 1992. Despite this, the Kola Superdeep Borehole remains the deepest artificial point on Earth, offering valuable insights into the Earth's composition and the challenges of extreme engineering.

How to visit

Visiting the site of the Kola Superdeep Borehole is not easy. The site of this expedition is located in the Kola Peninsula, Russia, which is off the beaten track for a foreign tourist. Be prepared to travel in a cold, windy, snowy environment. Reaching this site will be an adventurous road trip that will require your determination and strong will.