Ocean size and names Nearly 71 of the Earths surface is covered by oceans 4 major oceans ranked by size Pacific Atlantic Indian Arctic Southern Ocean proposed considered an extension of Pacific Atlantic and Indian Oceans and covers the waters that surround Antarctica ID: 1023039
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1. Oceanography notes (part 1):
2. Ocean size and namesNearly 71% of the Earth’s surface is covered by oceans.4 major oceans ranked by size: Pacific, Atlantic, Indian, Arctic. (Southern Ocean [proposed] = considered an extension of Pacific, Atlantic, and Indian Oceans, and covers the waters that surround Antarctica)
3. Water distribution:97.2% of all water on Earth is seawater.
4. Ocean depths:Average depth is 3688 m (12,100 ft. or ~ 2.3 mi)Deepest: Mariana Trench, 10,994 m (6.83 miles deep = 36,070 ft.).
5. Currents:Currents in the ocean can be affected by differences in wind / air pressure, temperature, Coriolis effect, salinity and density.
6. Sea floor features:
7. Coastal features:Continental Margin = transition from continent to nearby ocean floor (next two combined)Continental Shelf – Part of the continent which is under water (a shallow area). Significant due to large amounts of fish, minerals, oil/gas, sand/gravel in this area.Continental Slope – The edge of the continent; ocean drops off to deep water.
8. Continental slope parts:Submarine Canyons – Canyons cut into the continental slope by turbidity (sediment), currents / earthquakes (mud, sand, and water).Continental Rise – A gently sloping area at the base of the slope. Formed by turbidity flows, may be miles thick.
9. Ocean floor features:Abyssal Plains – The bottom, 10,000 to 20,000 feet deep. They are the flattest places on the planet as sediments have smoothed out the otherwise irregular ocean floor. Abyssal Fans – Fan shaped deposits at the end of many large rivers.
10. continental shelfcontinental shelfcontinental slopecontinental slopecontinental riseislandmid-ocean ridgeguyotseamount
11. Other seafloor features:Sea Mounts – Submerged volcano peaks; volcanoes that haven’t yet reached the surface to become islands. Guyots – Flat top seamounts, tops were cut off by wave action.
12. Ridges:Mid-Ocean Ridges – Mountain ranges which cross every ocean near the basin centers. New sea crust can form here. Hydrothermal Vents – Form along mid-ocean ridges where mineral heavy water escapes from cracks in the hot, new, oceanic crust.
13. Final features:Trenches – Deep troughs near continents. Where sea floor crust is pushed down into the earth and melted.Fracture Zones – Where mid-ocean ridges are broken by faults.
14. Oceanography notes (part 2):
15. Ocean study:Little was known before Sonar, invented in 1920’s. (Sonar = SOund Navigation And Ranging)The world’s largest wilderness.
16. Sea Water:Salinity – The dissolved solids in seawater. 3.5% of seawater is dissolved minerals / saltsMeasured in parts per thousand (ppt) “32 – 37 o/oo” [compare to %]Salts in seawater: Sodium Chloride (NaCl or ions) = ~ 85%
17. What Affects Salinity?Salinity increases with land runoff, evaporation, volcanic eruption, formation of sea ice.Salinity decreases with precipitation, melting of icebergs, sea ice.
18. The pycnocline:Why does the temperature spike where it does?Why does the salinity spike where it does?
19. Currents:Currents in the ocean can be affected by differences in wind / air pressure, temperature, Coriolis effect, salinity and density. Tsunami source??
20. Pacific Plate dynamics:
21. Pacific Plate dynamics:
22.
23. OLD: Ocean depths:Average depth is 3790m (12,430 ft.)Deepest - Mariana Trench, 10,923 m (6.86 miles deep = 36,200 ft).