OceanographyThompson Research VesselPolar views of EarthDistribution of Land and WaterDiagram of land/water by latitudeWorld map showing land/water distributionProgress in research vesselsHMS ChallengerKilo MoanaSonar process—single beamSonar process—multibeam and sidescanSea-floor landforms—CaliforniaSatellite AltimeterAtlantic oceanic ridgePacific and Indian Ocean FloorH:\ES106\PowerPoint\AN12_001.movAtlantic Ocean FloorSeismic data and interpretationCollection of sea-floor sediment coresSea floor sediment• Derived from land: ‘terra’– Terrigenous– Composed of sand, silt and clay• Derived from organisms: ‘biota’– Biogenous– Composed of shells and skeletons of marine animals and plants• Direct precipitation from sea water: ‘hydro’– Hydrogenous– Salts, calcium carbonate, metal oxides, metal sulfides (near sea-floor hot springs)PlanktonMarine Sediment distributionOffshore oil platformMethane Hydrate sampleMethane Hydrate burningSalt productionManganese NodulesSubmerged edge of continental crust• Function of amount of water in the sea• And number and size of oceanic ridgesBasin size vs. ridgehttp://geography.berkeley.edu/ProgramCourses/CoursePagesFA2002/Geog40/Geog40.Week7.htmlActive Continental Margins• Narrow continental shelf• Deep sea trench catches terrigenous sediment• ‘Accretionary Wedge’ of caught sediment• At convergent boundary of plateshttp://serc.carleton.edu/research_education/cyberinfrastructure/navdat/questions.htmlConvergent Lithospheric Plates• Oceanic plate is subducted• Deep-ocean trench is formed• Volcanism above subducted platehttp://serc.carleton.edu/research_education/cyberinfrastructure/navdat/questions.htmlActive continental Margin—locationDeep-Ocean Trenches• Active continental margins• Other convergent plate locations• Most are in the Pacific OceanPacific and Indian Ocean FloorSea-floor landforms—CaliforniaPassive Continental Margin• Continental shelf• Continental slope• Continental risePassive continental Margin—locationPassive continental Margin—cross sectionDeep sea sediment fansTurbidity currentDiscovery of Turbidity CurrentsAtoll formationAtollOceanic Plateaus• Figure 10-19—Oceanic PlateausPacific and Indian Ocean FloorAtlantic Ocean FloorPacific Lithosphere Actionhttp://www.soc.soton.ac.uk/CHD/classroom@sea/carlsberg/science/oceanic_constr.htmlOceanic Ridge--AtlanticOceanic Ridge—IndianOceanic Ridge—PacificOceanic plate divergencehttp://www.soc.soton.ac.uk/CHD/classroom@sea/carlsberg/science/constructive_margins.htmlRift valleys on oceanic ridgesKaiko•ROV• 10,911 m 1995• Lost in 2003• 7000 m-capable replacement in 2004Kaiko systemshttp://www.jamstec.go.jp/e/about/equipment/ships/kaiko7000.htmlKaiko on sea bedhttp://seawifs.gsfc.nasa.gov/OCEAN_PLANET/HTML/kaiko.htmlChallenger Deep shrimphttp://www.mext.go.jp/english/news/1998/07/980705.htmAlvin• Manned• 4000 m maximum depthBlack smoker with sulfide chimneyLink to other Alvin photoshttp://ocean-ridge.ldeo.columbia.edu/courses/subgeol/hot_springs.htmlFormation of Black
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