11.1 Flashcards
How much of the earth is covered by oceans?
A little over 2 thirds
What are the 5 major oceans labeled biggest to smallest?
Pacific Atlantic Indian southern Arctic
What are the low points on earths surface called?
Basins
What are oceans?
Basins into which water has flowed and accumulated
What are oceans so important
Controls earth temperature, making the planet liveable; they create the weather patterns; and they are the source of the water that falls as fresh water on land, supporting all life forms
How long have oceans been on earth
Scientists believe about 3 billion years
How long ago did the planet form?
4.5 billion years ago
How did oceans form?
Earth Started out as a hot ball of molten rock. The outside of the earth gradually cooled, but heat continued to be released deep within the planet by volcanoes. Water trapped inside the volcanic materials was also released into the atmosphere as water vapour. As the water vapour cooled and condensed, it fell to earths surface as precipitation. The water started collecting in the lowest parts of earth surface, ocean basins
What’s another way oceans formed?
Came from the ice on comets that hit the young earth
What are 5 features on land taht are also in the ocean?
Mountain ranges, valleys, flat plains, canyons, volcanoes
What are the oceans 2 distinct parts called?
Ocean basins and continental margins
Ocean basins?
The large middle part of the ocean
Continental margins?
Rising outside edges of the ocean
What do storm waters do?
Erode coral reefs
What do icebergs do on the ocean?
Gouge deep grooves in the ocean floor
What’s the greatest in shaping the ocean floor?
Tectonic processes
What is the entire surface of the earth made of?
Large sections of rock called tectonic plates
What do tectonic plates lay on top of
Float over a layer of molten rock called magma
How do two plates push apart
When the magma heats up it rises
What are the two type of tectonic plates?
Oceanic and continental