FACT: The deepest artificial(man-made) point on earth is over 12km beneath the surface of the Kola Peninsula. At over 12 km down the hole does not even reach half way through the Atlantic plate on which the site sits. The initiative was started in parallel with the space race by the USSR in a bid to study the Mohorovičić discontinuity or ‘Moho’ which is a mysterious plane where the crust and the magma mingle and mix.
Drilling was finally stopped in 1994 after scientist discovered to their surprise that the crust would start behaving like a very viscous liquid, such as melted plastic which would fill in an new holes which were drilled.
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