I like this idea, and I think it's an interesting take solving the problem. Maybe the earthquake would be more likely to target any island/plot of land that has a player built structure on it. I have a slightly different take on it. I think that every, I don't know, 45 days (maybe random, to make it more interesting?), you are told that the island you are in is going to collapse in 5 days and you have to build a boat. Then you have to build it and get off the island sometime in those 5 days and you shipwreck on another island with some your inventory missing, including your backpack if you have one. Maybe the better boat you build, the more stuff you get to keep? So it's not a reset, but you can lose a lot. Kind of an eternal cycle. Your idea definitely does this, but on a much more player-manageable pace.