Other mistake: At the end when they are rescuing Harry from the mine, we see a helicopter land and kick up tons of volcanic ash. Given the destructive nature of ash to the engine (as seen in the earlier scene), it would not make any sense to have a helicopter operate anywhere near the area.jerimiah
Plot hole: After the pyroclastic explosion Rachel, Harry and the kids get into the mine. There are a lot of things from Rachel's son in there: Sodas, chips, tapes and a tape player/recorder among them. There is a shot in which we can see a pile of tapes on the player, in almost perfect order. But if we consider that the whole town collapsed because of the earthquake occurred before the eruption, then those tapes must have fallen down, surely?