Mountain Formation
Mountains are Earth’s highest
landforms. They form as the crust folds,
cracks, and bends upward because of the
movements of Earth’s plates.
Most of the highest mountains form
where continental plates collide. As the
plates push together, their edges crumple and fold into mountains. The Himalayas,
Earth’s highest mountain range, formed as the Indian plate pushed into the Eurasian
plate. The plates are still pushing together, and the mountains are still getting taller.
At some places, continental and oceanic
plates collide. Because continental rock is lighter
than seafloor rock, the continental plate moves
up and over the oceanic plate. The Cascade
Mountains, near the Pacific Ocean, formed this
way.
Mountains do not form only at the edges,
or boundaries, of plates. Some mountains form
where pressure from movement at the
boundaries pushes a block of rock upward. The
Grand Tetons of Wyoming rise straight up from
the flat land around them.
Plates that pull apart leave gaps between them. Magma bubbles up between
the plates. Magma is hot, soft rock from Earth’s mantle. Magma builds up along the
cracks, forming long chains of mountains under
the ocean. The mountains are called mid-ocean
ridges. The Mid-Atlantic Ridge is Earth’s longest
mountain range. It separates the North American
and Eurasian plates in the North Atlantic and the
South American and African plates in the South
Atlantic.
√How do most of the highest mountains form?
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7. Mountain Formation