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World's Deepest Hole
If you have read my other hubs ‘The London Underground – The History’ and ‘The Glasgow Subway’ then you’d be aware of how we humans have been digging underground structures for many years now. Yet this raises the question, what is the furthest that we humans have dug into the Earth? I mean if Hollywood is to be believed, the technology to get humans into the Earth’s core (safely) is just around the corner – aka The Core.
Unfortunately for any science fiction fans the technology to drill right to the centre of the Earth is quite some way off. At present, we humans haven’t even managed to penetrate beyond the Earth’s crust – though in recent years, scientists drilling in the Atlantic, just off the coast of Puerto Rico believe that they are close to penetrating the Earth’s mantle – the next layer down after the crust. Led by Dr Damon Teagle of Southampton University, the team hopes to reach the Earth’s mantle in coming years.
This hole however is not the deepest hole created by man. You may well be wondering why if this hole has nearly penetrated the Earth’s mantle; a layer which no human has as yet being able to reach, why it is not deepest hole dug by man. And the answer is due to the fact that the Earth’s crust is not evenly deep. There are places where the Earth’s crust is goes deeper and other places where it does not stretch so thick. In fact the hole created by these scientists
Anyhow, the deepest hole which we humans can be said to have created is the Kola Superdeep Borehole. Located in the Pechengsky District on the Kola Peninsula in Russia, work initially began back on 24th May 1970, with the goal of seeing how deep we humans could drill underground. By 1989, the hole reached its ultimate depth of 12,626 metres (or 40, 230ft) and as such, is still the deepest artificial point on the planet.
It should be noted though that due to the unequal depth of the Earth’s crust, the Kola Superdeep Borehole has only managed to drill to somewhere between a third and half of the Earth’s crust in that specific vicinity. The reason why drilling came to a stop in the end was due to the fact that the temperature at that depth was exceeding 300°c. (570 °F) At those temperatures the drilling equipment could no longer function and after much frustration, it was agreed in 1992 that any attempts to drill further would be terminated.
For the next 12 years, the Kola Superdeep Borehole remained for geologists, etc. to carry out certain scientific research experiments on the Earth’s crust. Yet after 2005 due to lack of funding, it was agreed that the hole would be closed off. It took a subsequent 3 years to actually take all the equipment out of the hole, partly fill it in, etc. Visiting the site nowadays, the only give away to the hole actually being there is a large metallic plate covering the top of what’s left of the hole.
Despite the failure of the initial Soviet experiment to see how far one could dig into the Earth, geologists have managed to make several discoveries in the area of geology, thanks to the usage of this hole. One such discovery was the fact that as you go deeper into the Earth’s crust, the rock doesn’t change suddenly from Granite to Basalt rock like it used to be assumed. Instead the rock slowly changes from Granite to Basalt the further down you go.
What also surprised geologists was the discovery of water deep within the rocks at that surface level. This led the geologists to conclude that because the water was located at that depth, it meant that the water came up from deeper in the Earth, rather than seeping downloads from the surface of the Earth to that depth in the crust. Also, geologists discovered an extremely large amount of Hydrogen gas trapped in the rocks of the crust at that level; something no geologist would have guessed beforehand.
Although the experiment failed in regards to the Soviet Union not being able to claim to be the first nation to have reached beyond the Earth’s crust, they did manage to go further than the American lead project to dig into the Earth with the goal of reaching the Earth’s mantle. In my opinion however the depth at which this hole went is an achievement to the human spirit and shows how when a group of people come together with the aim of achieving a specific goal (be it walking on the Moon or reaching beyond the Earth’s crust) amazing results can be created!