| Why is there more water than land on earth?|
|Question Date: 2013-04-25|
It has to do with the different kinds of rocks
in the Earth's crust: continents are made of
granite, and ocean crust is made of basalt. The
more granite there is, the more continent there
is, and the more of the Earth's surface rises
above the ocean basins. Water fills the basins.
Right now, there is more basin than continent, and
so more ocean surface than land surface.
The surface of the Earth is covered about 70%
by water and it may seem like most of Earth is
composed of water, but actually it's a much
smaller amount of water compared to the rocky
planet - about 0.5% of the whole entire planet is
Water is the most important resource on Earth,
and more importantly it sustains life. Although
75% of Earth is covered in water, Earth is mostly
made of rock. In terms of weight, only 0.5% of
Earth's weight is water. It looks like there is
more water because water pools in low and deep
basins, like lakes, streams, and oceans.
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