The document discusses the formation of the Earth and its oceans. It describes how approximately 225 million years ago, all the continents were joined together in a single landmass called Pangaea. It provides details on the three major oceans - the Pacific, Atlantic, and Indian oceans, including their areas, average depths, and deepest trenches. The document also covers various topics related to oceans, such as salinity, temperature, tides, currents, resources obtained from oceans, and the impact of marine pollution.

2. THE OCEAN AND MAN

3. AT THE TIME OF ITS ORIGIN, THE EARTH WAS A MOLTEN
SPHERE

4. WORLD OCEANS
The inter connected body of water on the earth’s far
face, comprising all oceans is called the World Ocean

5. PANGEA
It is believed that about 225 million years ago , the
land we see today existed as one land mass. That
large continent is known as PANGEA.

6. THE PACIFIC OCEAN
 Area : 165.2 Lakh sq. km
 Average depth : 4270 Metres
 The deepest Trench : The challenger trench (11033 Metres)

7. THE ATLANTIC OCEAN
Area : 82.4 Lakh sq. Km
Average depth : 3700 Metres
The deepest Trench : The Puerto Rico Trench (8618 Metres)

8. THE INDIAN OCEAN
Area : 73.4 Lakh sq. Km
Average depth : 3960 Metres
The deepest Trench : The Wharton Trench (7725 Metres)

9. SALINITY OF OCEAN WATER
Salinity of ocean is the amount of salt present in sea water

10. TEMPERATURE
The temperature of the ocean water ranges between -2oc to 33oc

11. MOVEMENTS OF OCEAN WATER
The variations in temperature, salinity and density of
ocean water, and gravitational pull can be the movements
of ocean water.

12. SAND RIDGES
To prevent sea erosion, nature kinds its own solutions.
The most important of these is the formulation of sand
ridges.

13. CHAKARA
This is a special phenomenon seen only in the Arabian Sea.

14. STORM WAVES
Storm waves rise from 18 to 30 metres high. They threw
everything that lies close for the shore far way.

15. SEISMIC WAVES OR TSUNAMI
The earthquake and vollunoes that erupt under the sea
create huge waves. These are called Seismic waves or
tsunami.

16. TIDES
Tides are the periodic rise and fall of water level in the sea.

17. TIDES AND THE MOON
There is a gravitational attraction between the earth, the
moon and the sun.

18. TIDES AND THE SUN

19. THE MOON THAT GOES ROUND THE EARTH
The moon takes 27.32 days to go round the earth. This
is know as one sidereal month.

20. OCEAN CURRENTS
Besides the waves and tides, the water from the sea flows
from one place to another. These are ocean currents.

21. A STOREHOUSE OF MINERALS
Almost all the minerals found on land are also found in the sea.

22. SEA AS A SOURCE OF FOOD
Fish is one of the important food of man. Japan, Peru,
China, Norway, Russia and Britain are the major
fishing centres of the world.

23. SEA WATER DISTILLATION
In the processed sea water distillation, the sea water is turned
into water vapour using Solar energy. The vaporized water is
the condensed and fresh water is obtained.

24. ELECTRODIALYSIS
The process of removing salt from sea water using
electricity is electro dialysis.

25. MEDICINES FROM THE SEA
That fat from some type of fish is processed to obtain
fish oil and fish capsules.

26. PETROLEUM AND NATURAL GAS
Petroleum and natural gas are drilled from the ocean
floors from different parts of the world. Petroleum is
mined from the coast of Mumbai (Mumbai High) also.

27. THE SEA AND CLIMATE
Compared to the sea, land gets heated or cooled very fast.

28. OCEANS A SOURCE OF ENERGY
Energy can be produced from sea waves, tides and ocean
currents.

29. MARINE POLLUTION
We are polluting our marine environment with increasing
amounts and varieties of waste products originating with our
expanding technology, without full knowledge of the way in
which these materials may interact with our surroundings and
eventually affect our well-being.

31. Sumesh. P
Social Science
Reg No. 16914303035