The Russians did it–it took them twenty four years. They were stopped by the heat.
Despite the scientists’ efforts to combat the heat by refrigerating the drilling mud before pumping it down, at twelve kilometers the drill began to approach its maximum heat tolerance. At that depth researchers had estimated that they would encounter rocks at 100°C (212°F), but the actual temperature was about 180°C (356°F)– much higher than anticipated. At that level of heat and pressure, the rocks began to act more like a plastic than a solid, and the hole had a tendency to flow closed whenever the drill bit was pulled out for replacement. Forward progress became impossible . . .
A bunch of old theories about the Earth’s crust were disproven by that drill. I can remember being taught some of them in school — like that the crust is granite over a layer of basalt. Nope. ‘Tisn’t either.
The article’s by Alan Bellows.
