• lnxtx (xe/xem/xyr)@feddit.nl
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    2 days ago

    […] will consist of 60 km of tunnels buried 500 metres down in 1.9 billion year old bedrock.

    Are 500 meters deep enough?

    • Xavienth@lemmygrad.ml
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      2 days ago

      I mean, really the only thing that’s gonna expose them is plate tectonics. Just to give a sense of scale, America and Europe are diverging by 4 cm/yr, so will be 500 metres farther from each other, horizontally, in about 10,000 years. Geologically stable regions (called cratons) would not experience such motion vertically for much, much, much longer.