The World’s Deepest Structures
In keeping with tradition, this week I’ll be taking a look at the deepest structures in the world. Having celebrated the most visible of our achievements, it seems only fitting that I turn my figurative eye to where the majority of our engineering goes- the invisible!
I’ve had to cheat a bit to keep this list interesting. I’ve only allowed one borehole, or else we’ll just have oil explorations everywhere. Similarly, I’ve limited each mine to only be represented by its deepest shaft to save this becoming a tour of our deepest mines. As Google would put it- I’ve removed to similar duplicate results…
Schacht Asse II Repository
At 768m, this German ex-salt mine is already nearly as deep as most of the world’s tallest buildings are tall. Most of the depth was achieved in its first two years (1906-1908), however it was used as a potash and then salt mine until 1964. Now it lives out its days as a nuclear waste store.
Mizunami Research Laboratory
Another store for radioactive waste, this Japanese research project is now 1000m deep. The aim of the MIU Project is to research the techniques required in the burial (or geological) disposal of radioactive waste; one of the primary challenges in nuclear energy.
Sudbury Neutrino Observatory
Buried 2100m underground in Ontario, Canada lies a neutrino observatory. Constructed in 1999, this 18m ball of heavy water is tucked away from cosmic rays so that the neutrino interactions can be more easily distinguished. I’m not even going to attempt to explain this- so checkout Nobel Prise winner Art McDonald’s explanation.
The only still working mine in this list, the TauTona mine in South Africa is approximately 3900m deep. Initially sunk in 1957, this literal gold mine is one of the most profitable of its kind; even if the substantial depth means the rock face temperatures achieve 60deg!
Kola Superdeep Borehole
If the name doesn’t give you a hint of its depth, that this borehole was the basis of a myth that we dug a well to hell should be! Starting in 1970 the Soviet Union set off on a project to drill as deep as possible into the world’s crust. Achieving 12’262m in 1989, they still hold the record for the deepest artificial point on Earth; where they discovered mud ‘boiling with hydrogen’.