I used to fly tours out there for the red rash early in my career. White Island experiences 100's of earthquakes a day somedays but mostly only minor and you'd never know unless you were looking at the seismographs. About the end of my time there I spent two days with the geologists ferrying them around while they installed equipment. That was around the time of the first of the big Christchuch quakes in around 2010/11. We were on our way out when all their phones started pinging, much conversation followed in the aircraft about CHCH going off. WI is a very interesting place and as was said above eye opening when a section of track that you walked yesterday or this morning isn't there anymore. I would not be surprised if this quake is just a warm up.