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Geological Oceonagraphy

  • 71% of the earth is covered by water

    • N. Hemisphere ~ 60%
    • S. Hemisphere ~ 81%
  • Oceans are the main source of saltwater

    • 5 oceans that scientists identified but refer to as the main bodies that create waves, currents, and other ocean phenomena
    • Pacific, Atlantic, Indian, Southern, Arctic
    • Out of the 5, the Southern is the newest, relatively identified
    • Pacific is the largest/deepest
    • Atlantic is the second largest, and the smallest is the Arctic. The Southern Ocean is the second smallest
  • Earth is created based on density

    • Density: how much something weighs in a particular area
    • The more weight is spread out, the easier it is to manage
    • Ex) An 80-pound cell phone versus an 80-pound ceiling. You can hold up the latter in one hand
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    1. Oceanic Crust (Oceanic plates/Continental plates)
    • Younger, thinner, but extremely heavy
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    1. Continental crust
    • Older, thicker, but lighter
  • Both of them are lighter than the mantle

  • Diverging plates vs Converging plates

    • Diverging plates:
    • Move away from each other
    • Forms mid-ocean ridge
      • Big crack in the Atlantic Ocean, from the N. Pole to S. Pole, the only part of Earth where new land is being formed constantly is in the Atlantic Ocean
    • Convergent plates:
    • 2 oceanic crusts form a subduction zone
      • Deep sea trench
      • Lots of lifeforms in these environments are undiscovered
  • Subduction zones: The region where an oceanic plate sinks down into the asthenosphere at a convergent boundary, between continental and oceanic plates

  • Hydrothermal vents:

    • Organisms are constantly being found and identified in the hydrothermal vents, they’re a land of their own
    • Lots of bacteria and fish
  • The Pacific Ocean has converging plates, the Atlantic Ocean has diverging

  • Further elaboration: You can walk around 100 yards in the Atlantic Ocean on the East Coast and still be only ankle high. However, if you take a few steps in the Pacific, you’ll be met with a steep drop because there is only a tiny portion of the water is shallow

  • Earthquake activity is increased towards the Pacific, a tsunami is formed by earthquakes, and there’s more earthquake activity there

  • A huge amount of energy in a small space increases its pressure. The pressure creates a massive tsunami, and the drastic change of slope forces the water to be pressurized

    • Earthquakes have to happen in the open ocean