1. Ch. 19 The Ocean Basins
Sect. 19.1

2. Oceanography
The study of the physical characteristics, chemical composition and life forms of the ocean
Matthew F. Maury - began early study in 1850’s using records from navy ships

3. Why Study Oceanography
To Feed Us - Aquaculture
To predict weather
Mineral Resources

4. Global Ocean
Covers 3/4 of the earth’s surface (this is the most prominent feature on Earth!)
contains 97% of all the water on the earth
Totals 1/800 of Earth’s total volume
5 oceans: Pacific, Atlantic, Indian, Arctic and Southern (Antarctic)
smaller areas of the oceans are called seas

6. Pacific Ocean Largest, Deepest (contains more than ½ the ocean water)
Has many trenches and few abyssal planes
Ring of Fire
Deepest Trench-Mariana Trench

7. Atlantic 2’nd largest ocean Shallowest (avg. depth 3.9km)
Many sea routes between eastern and western hemispheres

8. Indian Ocean 3’rd largest less than 1/2 the size of the Pacific
Contains many ridges
Monsoons

9. Southern Ocean (Antarctic Ocean)
Coldest
Least Salty
Extends from the tip of Antarctica to 60 degrees South latitude
Contains largest current

10. Arctic Ocean Smallest Mostly surrounded by land
Central part permanently covered with ice and surrounded by water in summer.
Completely frozen in winter

11. Technology in Ocean Exploration
Drilling Ships
JOIDES Resolution
Take Core samples

12. Submersibles
Underwater research vessels including the following:

13. Bathysphere
One of the first that was linked to the surface with a cable

14. Bathyscaph
Self-propelled
Free-moving
Alvin and Nautile
Alvin

15. Robotics
Argo and Jason Jr
Used to discover the Titanic

16. Size of Jason Junior

17. SONAR Sound Navigation and Ranging
consists of a transmitter and receiver
sound waves are used to map and make profiles of the ocean floor

18. Speed = Distance Time Distance = Speed x time Time = Distance Speed
* Transmitter sends out sound 1500 m/s
* Sound waves are reflected back to receiver
* The time elapsed gives depth or distance:
Speed = Distance
Time
Distance = Speed x time
Time = Distance
Speed

19. …it would take 125 years to totally map the ocean floor using sonar…

20. …these days we can use satellite altimetry!
The bumps & dips on the ocean’s surface mimic the topography of the ocean floor.
SEASAT (and later GEOSAT) circle the earth; their sensitive radar altimeters send data used to create ocean floor maps.