The island area is about to start its mysterious tremor episode. This is quite common and has been as good as Old Faithful in the last few years. Of course, don't rely on past performance here, you never know when things will change.
These are all small adjustments that set up for the eventual big one. This type of earthquake, when it happens, is a 'slow rumbler' and should not affect building on sound foundations. The big swoosh of water is another story!