georefid:1990-044192SEDIS Publication Catalogueana.macario@awi.dehttp://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-06-23T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=1990-044192<gco:CharacterString>Manihiki Plateau; results of recent resource-oriented shipboard investigations and discovery of a major ?mud volcano complex</gco:CharacterString>1990-01-01publicationgeorefid:1990-044192Hill, Peter J.Bur. Miner. Resour., Geol. , and Geophys., Canberra, AustraliaauthorCoulbourn, William T.Univ. Hawaii, Honolulu, HI, United StatesauthorGlasby, Geoffrey P.N.Z. Oceanogr. Inst., Wellington, New ZealandauthorMeylan, Maurice A.Univ. South. Miss., Hattiesburg, MS, United StatesauthorAustralasian Institute of Mining and Metallurgy, Parkville, Victoria, AustraliapublisherdocumentHardcopyIn: Anonymous, Pacific Rim congress 90; proceedings3163-171Research cruises by HMNZS 'Tui' (1986) and RV 'Moana Wave' (1987) investigated the geology, geophysics and seafloor mineral resources of Manihiki Plateau in the central Pacific Ocean. Manihiki Plateau is a large (500,000 km (super 2) ) mid-ocean platform that rises 3000 m above the abyssal plains of surrounding ocean basins (depth, 5500 m). Its foundation evolved about 112 Ma ago by massive outpouring of basaltic lavas at a plate triple junction. The plateau is blanketed by a 900 m thick sedimentary section comprising (i) mid-Late Cretaceous volcaniclastic sandstones/siltstones grading upwards to limestones/chalks and (ii) 500 m of Tertiary nanno-foram chalks and oozes. Cores from DSDP 317 drill-site on the Manihiki High Plateau indicate that the volcaniclastic sediments contain native copper and some thin beds rich in organic carbon. Manganese nodules were dredged from 11 stations on the eastern and western marginal slopes of the plateau and adjacent parts of the Penrhyn/Samoan Basins. Abundant hauls of nodules were obtained from depths of 3300-5260 m. A field of volcanoes was discovered at the NE edge of the plateau and imaged by SeaMARC II.completedEconomic geology, geology of ore depositsOceanographyApplied geophysicsbottom featurescompositionEast Pacificeconomic geologygeophysical methodsgeophysical surveyshydrothermal alterationhydrothermal processesmanganese compositionManihiki Plateaumarine sedimentsmetal oresmetasomatismmineral deposits, genesismud volcanoesnodulesocean floorsoceanographyPacific Oceanprocessessedimentary processessedimentsseismic methodsSouth PacificSoutheast PacificsurveysSuwarrow TroughvolcaniclasticsEnglishgeoscientificInformation