On a remote and desolate tundra in north-west Russia, experts spent decades penetrating Earth's crust towards its center to discover the mysterious world beneath its surface. However, when they reached a record 40,230 feet, the otherworldly fossils discovered forced them to seal up the world's deepest borehole ever for good.
1. Mysterious Subterranean World
Humans have always been fascinated with the secrets of the universe, and thanks to satellites, we now know more about space than ever before. But as astronomers continue to stare skywards in wonder, prospectors have set their eyes on the equally mysterious subterranean world.
2. Battle For Exploration
Undeniably, our knowledge of what lies below Earth's surface is now much less than our understanding of the universe. While many people know about the space race between the US and the U.S.S.R. during the Cold War, few are aware of the equally fascinating battle to explore the secrets beneath Earth's dense shell.
3. The US Took The Lead
In the late 1950s, American and Soviet scientists competed to drill Earth's 158,400 feet thick crust straight down to the mysterious mantle that makes up a whopping 40% of our planet's mass. In 1958, the US took the lead, launching an elaborate experiment named Project Mohole.
4. Project Mohole Abandoned
Project Mohole was located near Guadalupe in Mexico. The American engineers responsible managed to drill the bed of the Pacific Ocean down to a depth of over 600 feet. Unfortunately, due to a shortage of funds, the operation was abandoned in 1966, 8 years after it had started. The Americans, therefore, had never reached the mantle.
5. The Soviets' Turn
Then the Soviets took over the mission to conquer the underground world. In 1970, a team of Soviets scientists started penetrating the earth below the sparsely populated Pechengsky District on Russia's Kola Peninsula. Their goal was simply to drill down as far as possible into Earth's dense crust.
6. Operation Slowed Down
Moreover, the Soviets were resolved to drill down to a depth of some 49,000 feet below the surface of our planet. And with specialist equipment, they even dug a string of boreholes branching off from a single principal cavity. But as time went by, their progress ground to a halt. Meanwhile, their competitors had made great advances of their own.
7. A Man-Made Marvel
In 1974, while the Lone Star Producing Company was drilling for oil in western Oklahoma, the American firm unintentionally created a hole that traveled over 31,400 feet into Earth's crust. It's absolutely a human-made marvel and was later named the Bertha Rogers hole.
8. A Marvelous Milestone
Disappointedly, Lone Star didn't find the oil they'd intended to look for, but the hole they dug remained the deepest on Earth for the following 5 years. In 1979, one of the Kola boreholes in Russia broke the record. And by 1983, the record 9"-wide hole, dubbed SG-3, had reached an incredible 39,000 feet below the surface of Earth.
9. Project Paused
After achieving such an impressive milestone, the Soviet researchers temporarily paused their work on the Kola Peninsula. For an entire year, they downed tools on the borehole, and visitors flocked to appreciate the fascinating sight. The operation was then restarted, but a technical problem drove it to a halt again.
10. A New Record
Not wanting to give up, the Soviets researchers discarded the previous borehole and started again from a depth of 23,000 feet. By 1989, the drilling had gone down to a record 40,230 feet into the earth. Those involved in the project were so encouraged that they believed that the borehole could reach 44,000 feet by late 1990.
11. Something Unexpected
More impressively and optimistically, experts predicted that the hole would reach its original aim of 49,000 feet by as early as 1993. But they would have never predicted that something bizarre was lurking at the bottom of the deep hole. As the drill inched closer and closer to the center of Earth, an utterly unexpected change happened.
12. Abnormal Temperatures
For the first 10,000 feet below the barren tundra on the Kola Peninsula, temperatures inside the hole went more or less as the experts had anticipated. But below that depth, temperatures shot up much faster. And by the depth near their target, the heat had gone up to a whopping 356 °F, a full 176 °F hotter than expected. That, however, wasn't all.
13. Strange Rock Conditions
In addition to the abnormally high temperature, the experts also noticed the rock at such depth was far less dense than imagined. Consequently, the thin rock reacted to intense heat in unpredictable and strange ways. And these conditions took a toll on their equipment, so in 1992, 22 years after the project had first started, they abandoned it permanently.
14. 2-Billion-Year-Old Fossil
However, researchers had managed to discover something fascinating before they sealed up the so-dubbed Kola Superdeep Borehole. For instance, at around 21,120 feet deep, they found tiny fossils of ancient marine plants. These relics were incredibly intact given the incredible time they had been encased in the rock that was believed to be over two billion years old.
15. A More Exciting Discovery
Additionally, an even more exciting secret was discovered at the deepest point of the Kola Superdeep Borehole. By measuring and analyzing seismic waves, experts had anticipated that the rock would shift from granite to basalt at about 10,560 to 21,120 feet below the surface. But they soon realized that this was not the case at all - at least not on Russia's Kola Peninsula.
16. Only Granite
To their surprise, scientists found only granite, even at the furthest reaches of the borehole. At last, they concluded the change in seismic waves as the result of metamorphic differences in the granite itself, rather than a shift from granite to basalt. However, that was not all.
17. Strange Subterranean Water
Researchers also discovered flowing water tens of thousands of feet below the surface, where none imagined it might exist. While some sensationalists have jumped on this phenomenon as proof of biblical floods, experts believe that the water is the result of strong pressure forcing oxygen and hydrogen atoms out of the rock, which then became trapped by impermeable rocks.
18. Remains The Deepest Hole
The Kola Superdeep Borehole has been labeled as an environmental hazard since its permanent closure after the collapse of the Soviet Union. But visitors can still see some relics from the site in a nearby town called Zapolyarny. Most impressively, the borehole remains the deepest human-made point on our planet, and the record is still yet to be beaten.
