Drilling began on 24 May 1970 using the Uralmash-4E, and later the Uralmash-15000 series drilling rig. Boreholes were drilled by branching from a central hole. The deepest, SG-3, reached 12,262 meters (40,230 ft; 7.619 mi) in 1989 and is the deepest artificial point on Earth. The borehole is 23 centimeters (9 in) in diameter.
Kola Superdeep Borehole can be found 10 kilometers from the town of Zapolyarny in the northern part of the Russian Murmansk region.
Geographic coordinates: 69.396511, 30.609849
After 24 years of digging, and several branches in the hole, the deepest branch of the Kola Superdeep Borehole stopped in 1994 at 12,262 meters (about 7.5 miles). It’s only nine inches in diameter at the bottom. It is still the deepest hole in the world, and the process of drilling was incredibly difficult. (For reference, the Mariana Trench is approximately 10,994 meters deep at The Challenger Deep—and it’s not a drilled hole.)
In terms of true vertical depth, it is the deepest borehole in the world. For two decades it was also the world’s longest borehole in terms of measured depth along the wellbore until it was surpassed in 2008 by the 12,289-metre-long (40,318 ft) Al Shaheen oil well in Qatar.
Has anyone ever tried to dig through the Earth’s crust?
Like the space race, the race to the explore this unknown “deep frontier” was a demonstration of engineering prowess, cutting-edge technology and the “right stuff”.
The US had fired up the first drill in the race to explore the deep frontier. In the late 1950s, the wonderfully named American Miscellaneous Society came up with the first serious plan to drill down to the mantle. The society-turned-drinking-club was an informal group made up of the leading lights of the US scientific community. Their crack at drilling through the Earth’s crust to the mantle was called Project Mohole.
The Soviets started to drill in the Arctic Circle in 1970. And finally, in 1990, the German Continental Deep Drilling Program (KTB) began in Bavaria – and eventually drilled down to 5.6 miles (9km). One of the biggest challenges the German engineers faced was the need to drill a hole that is as vertical as possible. The solution they came up with is now standard technology in the oil and gas fields of the world.
Two years before Neil Armstrong walked on the moon, US Congress cancelled the funding for Project Mohole when costs began to spiral out of control. The few metres of basalt that they were able to bring up worked out at a cost of roughly $40m (£31m) in today’s money.
Then it was the turn of the Kola Superdeep Borehole. Drilling was stopped in 1992, when the temperature reached 180C (356F). This was twice what was expected at that depth and drilling deeper was no longer possible. Following the collapse of the Soviet Union there was no money to fund such projects – and three years later the whole facility was closed down.
What did scientists find at the bottom of Kola Superdeep Borehole?
The Kola Superdeep Borehole led to a number of fascinating discoveries. For example, there is a lot of water underground! This discovery was one of the most important. Scientists believe that this water is actually trapped in the rocks that make up the Earth’s mantle and parts of the crust. They think it is trapped in the form of hydrogen and oxygen atoms. The drilling process released some of these trapped gas atoms, producing water. Scientists also discovered microscopic plankton fossils at around 6.7 kilometers below the Earth’s surface! Twenty-four different species of ancient microplankton were cataloged during the project. For all the effort and decades of work, this hole only went 0.2% of the way to the center of the Earth!
Have there been other super deep holes dug since then?
Some projects have also attempted drilling through the Earth’s crust underwater. Japanese drillship Chikyu is the most notable example. The ship is designed to operate in waters up to 2 500 meters deep. It is designed to drill a further 7 000 meters into the Earth’s crust. Its most recent expedition took place in 2009.
Despite the importance of the project, the huge drilling ship the Chikyu was built almost 20 years ago with this project in mind. The Chikyu uses a GPS system and six adjustable computer-controlled jets that can alter the position of the huge ship by as little as 50cm (20in).
Kola Superdeep Borehole History
When the plans for the Kola Superdeep were formulated at the end of the 1960s, Cold War competition drove geological research. When drilling near Zapolyarny began in 1970, in honour of the 100th anniversary of Lenin’s birth, the Russians were eager to smash the record for the deepest borehole. In 1979 the world record for drilling depth – 9583 metres, held since 1974 by the Bertha Rogers hole in Washita County, Oklahoma – was broken by the Kola Superdeep. In 1983, the drill passed 12,000 metres, but after reaching 12,066 metres on 27 September 1984, the drill broke down. Repairing the damage took ages, as new equipment had to be built. Drilling was eventually resumed from a depth of 7 kilometres, but slow progress over subsequent years can also be attributed to the difficulties they encountered drilling at such great depth.
The reason geologists chose Kola as the location for superdeep drilling is that the Fennoscandian Shield consists of very old rock, in some places the Precambrian crystalline igneous rock is exposed on the surface. Drilling deeper reaches the even older rock and enables us to see even further back into the history of the Earth. The Kola borehole encountered 2.7 billion-year-old rocks at 12 kilometers depth. The primary scientific goal of the Kola Superdeep was fundamental geological research. The secondary goal was the prediction of natural disasters based on analyzing bore cores. The Soviet Union proposed creating a network of superdeep boreholes, distributed throughout the Soviet Union: Globus. It would monitor global tectonic activity to predict earthquakes and other natural disasters. Boreholes were planned and sometimes started, for example, in Komi, in western and eastern Siberia, near the Caspian Sea, in the Dnepr-Don region, the Caucasus, and Turkmenistan. These are all mineral-rich areas, and gathering geological data that aids in identifying new oil fields and mineral deposits certainly played a role in choosing these locations.
From 1994 the director of the Kola Superdeep, Dr Huberman, continued research at onsite laboratories with significantly reduced funding. But the new governments were less and less interested in the Kola Superdeep. The plan to set up a network of superdeep boreholes was long forgotten, and the willingness to finance fundamental geological research faded away. International funding could not save the Kola Superdeep. After years of setbacks, the site shut down in 2008 – the laboratories were abandoned, the equipment and metal scrapped. For a few years there was still a small office in Zapolyarny, but even that has disappeared. The drilling tower has collapsed. What remains is a ruin.
The Kola Superdeep has captured the imagination more than any other borehole or geological research. Since it is a ruin, it lives on as a legend. The site could have been a museum and tourist destination, paying homage to fundamental scientific inquiry – even without glorifying the research. It could have been monument to the human yearning to know what the Earth is made of. Here’s a borehole, 12 kilometres deep. We used it, not to extract oil to fuel our cars, but to know what is there. One wonders how much this hole – now closed by a rusty metal cap – would be worth if it was a piece of land art by Walter de Maria. On the other hand, that it is a ruin, abandoned and crumbling, presents a powerfully poetic image that invites reflection on the value of scientific research. We might know more about what is inside the Earth through seismic measurements, but we have never been able to see further into the Earth than we did with the Kola Superdeep.
Kola Superdeep Borehole Current Status and Photos
The project was officially terminated in 1995, due to the dissolution of the Soviet Union, and the site has since been abandoned. In 2008 the Russian InfoCentre announced that the borehole was to be destroyed. The site is still visited by curious sightseers, who have reported that the structure over the borehole has been partially destroyed or removed.