After Attempting To Dig To The Center Of The Earth, The Super Hole Had To Be Sealed

Humans have lived on Earth for approximately 300,000 years, but there is still so much that has yet to be discovered. Around the time of the Space Race in the late 1950s, Americans and Russians wanted to find out more about the planet. They set out to dig some of the deepest holes in the world. See how far they were able to get and why they had to seal it shut.

Entering The Space Race

astronaut on the moon from apollo 11
Nasa/Getty Images
Nasa/Getty Images

The 20th century saw a lot of tension between the United States and the Soviet Union, which can be summed up by the events of the Cold War.

One of the biggest events that occurred was the Space Race with both countries trying to achieve new discoveries in spaceflight capabilities.

Heading Way South

Control room at nuclear missile base, outside of Moscow
Robert Wallis/Corbis via Getty Images
Robert Wallis/Corbis via Getty Images

While the Soviet Union and the United States were focused on going to space, they also were butting heads over things happening on earth.

Both countries wanted to figure out how close they could get to the center of the earth. This is something that hadn’t been done before and would be challenging with the limited technology of the era.

Starting At The Crust

Diagram of Earths interior structure showing inner core, outer core, mantle and crust
DEA/D’ARCO EDITORI/De Agostini via Getty Images
DEA/D’ARCO EDITORI/De Agostini via Getty Images

Around the time of the late 1950s, both America and Russia wanted to develop experiments to penetrate the earth’s crust.

The crust stretches for about 30 miles towards the center of the earth. It’s just a thin shell of the planet that accounts for less than one percent of the entire mass.

Heading Towards The Mantle

Diagram of the Earth's interior showing the crust (aluminium, silicate), the mantle (magnesium, silicate) and the core (iron, nickel)
DeAgostini/Getty Images
DeAgostini/Getty Images

After looking at the crust, the U.S. and the Soviet Union were ready to start making their way through the earth’s mantle.

The mantle is a layer of silicate rock situated between the crust and outer core of the planet and makes up about 67 percent of Earth’s mass and 84 percent of Earth’s volume.

The United States Starts Project Mohole

Map of Mexico with the new boundaries established by the Treaty of Guadalupe
DEA/G. DAGLI ORTI/De Agostini via Getty Images
DEA/G. DAGLI ORTI/De Agostini via Getty Images

In the late 1950s, the American Miscellaneous Society had the idea to start drilling down to the mantle. They called it Project Mohole after the Mohorovičić discontinuity, which is what separates the crust from the mantle.

They chose to do the drilling close to Guadalupe, Mexico through the Pacific Ocean floor.

Drilling In The Ocean

shot of the beach in mexico
Wolfgang Kaehler/LightRocket via Getty Images
Wolfgang Kaehler/LightRocket via Getty Images

Project Mohole was set in the Pacific Ocean because there are many advantages to drilling in the ocean.

According to the BBC, Earth’s crust is thinner in the ocean. However, the thinnest areas of the crust is usually where the ocean is the deepest. It was now time to start drilling.

The Project Got Shelved

Oil workers on drilling floor of a drilling rig
Giles Barnard/Construction Photography/Avalon/Getty Images
Giles Barnard/Construction Photography/Avalon/Getty Images

The Americans got to work on Project Mohole in 1958 and were able to drill as far down as 600 feet.

Unfortunately, the project had to be shelved in 1966 after the team of scientists lost their funding. America was never able to find the mantle, so now it was up to the Russians.

The Russians Were Very Motivated

a map of russia
Valentin Yegorshin/TASS via Getty Images
Valentin Yegorshin/TASS via Getty Images

After the Soviet Union learned about America’s failed attempt at drilling towards Earth’s mantle, they were ready to give it a shot.

Researchers began to make their way through the crust below the Pechengsky District in the early 1970s. The area rarely was occupied by people, so scientists thought it would be the perfect location.

The Main Goal For The Kola Superdeep Borehole

A workman drilling holes
Staff/Mirrorpix/Getty Images
Staff/Mirrorpix/Getty Images

The Soviets wanted to dig almost 50,000 feet into the surface of the earth at the Kola Peninsula. They had special equipment, so they could dig several boreholes from just one cavity.

This would be a very ambitious project with the ultimate goal of getting living samples of the mantle.

Americans Accidentally Make A New Hole

Oilfield pump in Oklahoma, USA
Adrian Greeman/Construction Photography/Avalon/Getty Images
Adrian Greeman/Construction Photography/Avalon/Getty Images

While the Soviet Union was working on the Kola Superdeep Borehole, the United States ended up making an entirely new hole on accident.

The Lone Star Producing Company was digging for oil in Oklahoma in 1974 and ended up creating the Bertha Rogers hole. It measured over 31,400-feet deep, which was equivalent to about six miles.

The Soviet Union Breaks The Record

Workers secure drilling pipe sections on an oil drilling tower
Andrey Rudakov/Bloomberg via Getty Images
Andrey Rudakov/Bloomberg via Getty Images

The Bertha Rogers hole became the deepest hole on Earth until 1979 when one of the Kora boreholes broke the record.

While the borehole was only nine inches wide, it was able to penetrate the earth with a whopping 39,000-foot depth. This seemed like a good place to stop for the Soviets.

The Soviets Ran Into Some Issues

Workers use machinery to move drill sections on the drilling floor of the oil derrick
Andrey Rudakov/Bloomberg via Getty Images
Andrey Rudakov/Bloomberg via Getty Images

After they broke the record for the deepest hole on Earth, the Russians thought it would be okay to pause their progress.

While a break was needed, there were some other issues with the project. This caused them to put it on indefinite hold until they could get sufficient tools and research.

The Wait Was Over

A view of Lake Seydozero on the Kola Peninsula
Lev Fedoseyev/TASS via Getty Images
Lev Fedoseyev/TASS via Getty Images

They got the project back up and running in the early 1990s with the goal of reaching a depth of 49,000 feet within the first few years.

They started at a location already 23,000-feet deep, but ran into some setbacks as they came closer to Earth’s core. This meant they would need to do some more research.

There Were Major Temperature Changes

Workers drill a hole
Mikhail Mordasav/AFP via Getty Images
Mikhail Mordasav/AFP via Getty Images

As the Russians got closer to Earth’s core, they noticed that temperatures were increasing far more than they expected. When they approached their target, the temperature rose to 356 degrees Fahrenheit.

This was 176 degrees Fahrenheit more than they were anticipating, which caused a lot of frustration amongst the researchers.

There Were More Setbacks

the kora superdeep borehole wielded shut
Rakot13/Wikimedia Commons
Rakot13/Wikimedia Commons

Not only was the temperature too hot for the researchers to endure, but there were other setbacks. The rocks at this part of Earth’s core were a lot denser than they thought they would be.

When this occurs, the rocks will react in unpredictable ways, which can be very dangerous.

Time To Give Up

site of the kora superdeep borehole in 2012
Bigest/Wikimedia Commons
Bigest/Wikimedia Commons

While the Russians made a lot of progress with the Kola Superdeep Borehole, they realized it was time to shut the project down altogether.

They spent a total of 22 years working on getting to the center of the earth and were able to discover a lot of new things such as fossils and plants.

What Was Found Inside The Kola Superdeep Borehole

kora superdeep borehole construction site
Andre Belozeroff/Wikimedia Commons
Andre Belozeroff/Wikimedia Commons

After spending 22 years drilling the Kola Superdeep Borehole, scientists were able to find some fascinating treasures.

The rocks in the borehole were over two billion years old and there was granite at the deepest part of it. There was also flowing water, which was either proof of a biblical flood or strong pressure that forced hydrogen and oxygen atoms out of the rocks.

The Status Of The Kola Superdeep Borehole Today

a superhole shot from above
Missing Files/YouTube
Missing Files/YouTube

The drilling of the Kola Superdeep Borehole officially stopped in August of 1994 shortly after the collapse of the Soviet Union. Then, the project was permanently shut down the following year and the hole had to be sealed.

Those who want to see some of the relics found from the project can visit them in a nearby town called Zapolyarny, but the actual site is considered an environmental hazard.

The Germans Did A Similar Project

a large man-made superhole
Manual dos Curiosos/Pinterest
Manual dos Curiosos/Pinterest

While America’s Project Mohole was the inspiration for the Kola Superdeep Borehole, there were other countries who tried their hand at their own superholes.

The German Continental Deep Drilling Programme created the KTB superdeep borehole in Windischeschenbach, Bavaria from 1987 to 1995. They were able to get 29,859-feet deep with temperatures that reached over 500 degrees Fahrenheit.

How Deep Did The Kola Superdeep Borehole Get?

kola superdeep borehole split image of the holes
Polimer News/YouTube
Polimer News/YouTube

At the end of their project, the Kola Superdeep Borehole became the deepest manmade hole on Earth and the deepest artificial point on Earth. It measured at 40,230-feet deep.

It was able to hold the record for two decades, but was dethroned in 2008 when the Al Shaheen oil well in Qatar broke the record at 40,318-feet deep. Considered an environmental hazard, the hole was sealed shut in 1995.