Multibeam echo sounders - Research vessel Scripps Institution of Oceanography R/V Roger Revelle depth Source: Scripps Institution of Oceanography http://woodshole.er.usgs.gov/project-pages/caribbean/movie1.html Source: Scripps Institution of Oceanography Multibeam echo sounders - Research vessel - Underwater vehicles - Remotely operated vehicle - Autonomous Underwater vehicle Woods Hole Oceanographic Institution ROV Jason Multibeam echo sounders - Research vessel - Underwater vehicles - Remotely Operated Vehicle - Autonomous Underwater Vehicle - Human Operated Vehicle Woods Hole Oceanographic Institution HOV Alvin Woods Hole Oceanographic Institution AUV Abe Source: Woods Hole Oceanographic Institution Source: Woods Hole Oceanographic Institution GPS used to measure satellite altitude Satellite measures range Sea surface height = satellite altitude - range Source: Aviso, CNES Source: Scripps Institution of Oceanography 1
Source: Scripps Institution of Oceanography : Hypsographic curve seismic waves Earthquake (P & S) seismic waves Source: J. Louie, UNR 2
Drilling (Ocean Drilling Project) - 1800 holes, deepest hole 7,000 JOIDES Resolution, Royal Naval Dockyard, Bermuda JOIDES Resolution Drilling (Ocean Drilling Project) Drilling (Ocean Drilling Project) Re-entry cone being lowed to the seafloor Drill bit Core Laying out core contents Marine provinces Mid-ocean ridge Deep ocean basin Continental margins 3
Marine provinces: continental margins Marine provinces: continental margins Marine provinces: active continental margins Continental shelf Continental slope Continental rise Ends at a subduction zone (trench) No continental rise Cape Hatteras, NC Marine provinces: continental margins Passive or active margins Erosion of the continental slope 4
Marine provinces: continental margins Marine provinces: continental margins Monterrey, CA Submarine Canyon Port Orford, OR Submarine Canyon Marine provinces: continental margins Marine provinces: continental margins La Push, WA Abyssal plains Volcanic peaks Below sea level -Seamounts/tablemounts >1 km tall -Abyssal hills <1 km Above sea level -Volcanic islands 1 km = 0.6 mile 5
Volcanic peaks originally associated with mid-ocean ridge magmatism Volcanic peaks due to a hotspot Hotspots Hotspots: Galapagos Source: Ocean Explorer Hotspots: Hawaii Lahaina, HI 6
Deep ocean trenches Central rift valley, faults, and fissures Central rift valley, faults, and fissures East Pacific Rise Central rift valley, faults, and fissures Volcanic features Richard D. Grigg Juan de Fuca ridge J. Lowenstern http://www.pmel.noaa.gov/vents/nemo/explorer/concepts/pillows.html 7
Hydrothermal vents: seawater migrates through cracks in ocean crust Black smoker Transform faults: offset axes of mid-ocean ridge White smoker http://www.ocean.udel.edu/extreme2004/geology/hydrothermalvents/# Transform faults active active active Groups of 4, each person choose a different line Draw the bathymetric profile roughly to scale vertically Label each marine province, tectonic plate, plate boundary, various seafloor features (hotspot, seamount, abyssal plain, etc), where there would be EQ, magma... Groups of 4, each person choose a different line Draw the bathymetric profile roughly to scale vertically Label each marine province, tectonic plate, plate boundary, various seafloor features (hotspot, seamount, abyssal plain, etc), where there would be EQ, magma... 8