Sedimentation on the continental terrace around New Zealand: A review

摘要: Abstract The New Zealand continental terrace is mantled mainly by terrigenous and biogenic sediments associated with subordinate but locally important authigenic, volcanogenic residual components. Modern sands muds prevail off Westland Hawkes Bay—Wairarapa where tectonically rising landmasses, several major rivers few coastal sediment traps ensure deliverance of much to the terrace. Relict gravels typically occur in zones modern sedimentation low like middle outer shelf Otago—Canterbury Waikato—Taranaki. are commonly which also dominate terrigenous-starved shelves around northernmost southernmost Zealand, slope. Shelf components molluscan, bryozoan foraminiferal clasts, whereas on slope foraminifers calcareous nannoplankton prevail. Both glauconite, main authigenic component, those upper slopes receiving little sediment. Volcanogenic grains prominent eastern marginal Central Volcanic Region North Island. Typically, Island northeast South have been reworked from older or derived directly volcanic rocks both. Around remainder a metamorphic plutonic-derived assemblage prevails. Sediment dispersal along primarily under influence storm-driven tidal currents semi-permanent ocean having effect. Beyond shelf, appears be downslope, partly through redepositional mechanisms including gravity slumps turbidity currents.