Date post: | 21-Apr-2017 |
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Environment |
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Origin Of Ocean Basins
Contents1. Introduction of Ocean2. Source Of Water3. How Oceans generated?4. Formation of ocean goes from three phases5. Evolution of oceans6. Divisions of Planet
Introduction of Ocean
• ocean is a body of saline water that composes much of a planet is hydrosphere which cover 71% of surface of Earth.
Source Of Water
• 1: Comets: Comet brought a large portion of water on earth.
• 2: Volcanic Outgassing: Water may also have come from volcanic erruptions condensing and forming rain.
How Oceans generated?• Earth is about 4.5 billion
years old but oceans are 3.8 billion years old.
• Two main theories describing how oceans formed.
• 1: Earth was formed with water and that this water come from the inside out.
• 2: Earth was dry planet with water brought here by other sources.
Formation of ocean goes from three phases
• 1: Initially there was only water vapour in atmosphere.
• Air and ground surface too hot for liquid.
• 2: Cooling of atmosphere led to condensation and rain.
• Ground surface still too hot for pooling.
• 3: Futher cooling of ground surface finally led to accumulation of liquid water on surface.
• Ocean formed 3.8 bilion years ago.
Evaloution of oceans• 180 million years ago, the
continents were united in a single supercontinent called Pangaea.
• Oceans were like a single body which covered the whole land called Panthalassa.
• Due to plate tectonic theory have since moved to their present position.
• Now there are 5 major o,ceans are present in world.
Tethys Ocean
• The Tethys Ocean was an ocean that existed between the continents of Gondwana and Laurasia.
• Due to plate tectonics movement “Tethys” ocean disappeared.
Divisions of Planet
• 1: Pacific Ocean• 2: Atlantic Ocean• 3: Indian Ocean• 4: Arctic Ocean• 5: Antarctic Ocean
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