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AUSTRALIAN PLATE. Te c t o n i c s. PACIFIC PLATE. 45 mm/yr. Lionel Carter NIWA. Wp 35 Mt/y. Sediment Supply. Uw 5 Mt/y. Wa 15 Mt/y. Lionel Carter NIWA. Going Hyperpycnal. In Cyclone Bola 40. 10 6 t discharged in 6 days. 2m thick fluid mud layer on continental shelf.
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AUSTRALIAN PLATE Te c t o n i c s PACIFIC PLATE 45 mm/yr Lionel Carter NIWA
Wp 35 Mt/y Sediment Supply Uw 5 Mt/y Wa 15 Mt/y Lionel Carter NIWA
Going Hyperpycnal • In Cyclone Bola 40. 106 t discharged in 6 days. • 2m thick fluid mud layer on continental shelf. • Organisms smothered but recolonized 2 months later after mud dispersed Photograph by Dave Peacock GDC, August 2002 Lionel Carter NIWA
Climate and sediment input - ENSO + + + Southern Oscillation Index + + + + + El Nino + + ? Major storm events from Lake Tutira Lionel Carter NIWA
Shelf Currents From Chiswell, 2000 Lionel Carter NIWA
Poverty Bay Circulation Scott Stephens, NIWA Lionel Carter NIWA
Forced Circulation offshore onshore Scott Stephens, NIWA Lionel Carter NIWA
Mud capture in shelf synclinal basins m 1 1 Lionel Carter NIWA
Response of the deep ocean flux * MD2121 Lionel Carter NIWA
Where to next? • How does climate affect sediment input? • How will future climate affect delivery? • Tectonic control on sediment input? • Hyperpycnal vs hypopycnal dispersal? • Is there distant transport of nutrients to e.g., Fe-limited fronts? Lionel Carter NIWA