Ever just wanna dig a deep hole?

Maybe it's just a guy thing but it's the second or third cool thing to do when you get to a nice beach, dig a deep hole.


Well boys, it's been done before.

Over forty years ago, researchers in the Soviet Union began an ambitious drilling project whose goal was to penetrate the Earth's upper crust and sample the warm, mysterious area where the crust and mantle intermingle...


The Russian researchers were also surprised at how quickly the temperatures rose as the borehole deepened, which is the factor that ultimately halted the project's progress. 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 without some technological breakthroughs and major renovations of the equipment on hand, so drilling stopped on the SG-3 branch. If the hole had reached the initial goal of 15,000 meters, temperatures would have reached a projected 300»?C (572»?F).


When drilling stopped in 1994, the hole was over seven miles deep (12,262 meters), making it by far the deepest hole ever drilled by humankind.

Read all about it.