To: library user
if left alone it would run out eventually. Perhaps in several months, perhaps a lot longer—the worlds first oil well, over 140 years old, is still producing, albeit at a very slow rate. The oil is in porous rock, so there’s no empty space. Sometimes the ground subsides a bit in old oilfields, but there’s no big cavern under there that will collapse.
Either that, or one very similar - there’s been a LOT of threads, and a Lot of repetition and redundancy, so the details get run-together-hazy after the first thousand posts or so...
;)