https://en.m.wikipedia.org/wiki/Plasma_deep_drilling_technology https://en.m.wikipedia.org/wiki/Plasma_deep_drilling_technol... Plasma drilling sounds like it

https://en.m.wikipedia.org/wiki/Plasma_deep_drilling_technology https://en.m.wikipedia.org/wiki/Plasma_deep_drilling_technol... Plasma drilling sounds like it could be useful - the plasma essentially melts the material surrounding the borehole into a glass as it drills down.