The Russians tried this on the Kamchackta Pennisula some time back. Lost their bore hole and string as I recall......
IOW its not the “drilling”, per se, its maintaining circulation and keeping the bore open to permit tripping out/in. We’ve improved the hell out of drill fluids, but this is a real stretch. >PS
IOW its not the “drilling”, per se, its maintaining circulation and keeping the bore open to permit tripping out/in.
Do you suppose their bore hole closed up on its own after their attempt? As you say, they had a hard time keeping it open. I'd like to think that a wound like that would heal itself, given what could escape from it.