Sedimentation at its extreme: how powerful are submarine caldera-forming eruptions (Kermadec arc)?

The objectives of IN2022_V02 were to survey and sample several submarine caldera volcanoes in
Rangitāhua/Kermadec arc to improve knowledge on eruption and transport processes during largemagnitude
eruptions under water. The targeted volcanoes were selected based on water depth, the
type of sediment sheets on their slope, and prior knowledge based on legacy surveys.

The scientific objectives of the voyage were:
1) To survey the sediment sheets on the flank of representative submarine volcanoes and test
whether dune-like (undulations) bedforms – if present – are derived from eruption-fed
sediment waves or mass-wasting deposits. The eruption style, eruption intensity, and
sediment volumes produced during submarine arc volcanic events are largely unconstrained.
This voyage aimed at collecting data to quantify magma flux of submarine eruptions by using
3D morphology of proximal sediment waves (dunes) deposited by eruption-fed sediment
flows.
2) Collect geophysical data to study the internal morphology of sediment waves. Based on
geophysical and core data, sediment fluxes and eruption discharge rates can be scaled,
providing. The morphology of sediment waves, water depth of the caldera, and rock
composition at the target volcanoes will establish eruption styles in the context of deep-water
caldera-forming silicic volcanism.
3) To improve models of volcanogenic tsunami. The initiation of volcanogenic tsunamis is
dependent on magma flux, sediment flux, and vent water depth. Combination of these three
factors at the target volcanoes will be assessed to infer risks and build hazards maps for
modern submarine volcanism (tsunamis and seafloor sediment flows). Outputs from seismic
reflection and coring surveys will provide a framework for benchmark assessment of the
tsunamigenic potential of submarine volcanism and raise awareness on the destructive ability
of associated volcanogenic flows.
4) Seismic surveys will be carried out to fulfil mandatory requirements for a future IODP drilling
campaign.