New submarine eruptions observed in the Kermandec Islands (New Zealand)

A submarine eruption has taken place a few days ago in the Kermandec Islands. The eruption was not directly observed, but a new large pumice raft has been spotted by NZ navy and others. The pumice is drifting 85 nautical miles south-west of Raoul Island on Thursday night (9 Aug).
The raft is 250 nautical miles long in length and 30 nautical miles wide, about 26,000 squake kilometer in size, i.e. roughly the size of Belgium, and can be seen on satellite pictures. This suggests that the eruption was significant in size.
It is not exactly known from which of the submarine volcanoes the eruption was from, but the most likely candidate is the Monowai seamount nearby, which is one of the most active volcanoes in the region and has in the past had eruptions almost every one or 2 years.