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have been worn down by forces of wind, water The terrain of many others has been eroded
and ice. Many mountain ranges of the world, away by water and wind over millions of years to
even near the equator, are covered with snow. create distinct and unusual landforms. As such,
These mountains like Himalayas are also the many plateaus are filled with landforms.
source of many rivers. The Block Mountains like Plains
Rift Valley in Africa are also the result of internal
A plain is a type of landform made up of a flat
forces of the earth. These forces produce a huge
area that can exist in valleys, lowlands, on
rift as a result of which some parts of the surface
plateaus or uplands. They are formed by a
of the earth rises above the surroundings and
variety of weather and geological phenomena
other parts sink below the surface. Such moun- including water deposits, ice, wind, erosion and
tains like, in Great Britain are also termed as even lava. Plains make excellent agricultural
Fault Block Mountains. The volcanic mountains ground in many places because of their rich soil
are a result of accumulation and colliding of lava and their relatively flat landscape. There are
given out by volcanoes. different types of plains including structural
Plateaus plains, erosional plains and depositional plains as
Plateaus, known variously as tablelands or flat- well as coastal plains and flood plains. Natural
topped mountains, are regions elevated thou- plant life on plains is dependent on the climate
sands of feet above their surroundings. They are and can range from thick forests to grasslands
found on continents around the world, in coun- and everything in between.
tries ranging from Algeria to Mexico, from
Mongolia to Zimbabwe. In Antarctica, which has
a greater average elevation than any other
continent, most of the land outside of the moun-
tain ranges can be considered plateaus. Covered
by thick ice, many of these areas have no names.
Islands
A smaller tract of land completely sur-
rounded by water is called an Island. Mountains
rising from the ocean floor also form island.
Examples are Lakshadweep and Andaman and
Nicobar island of India, though their mode of
formation is different.
Some plateaus around the world exist at such
great heights that their climate is harsh and living Lakes
conditions are bleak. Others, at much lower A lake is a body of water that is surrounded
elevations, offer more favorable conditions. The by land. There are millions of lakes in the world.
terrain of some plateaus is unbroken and flat. They are found on every continent and in every
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