Competitive Exams: Mountain Building
The most important is with the lithosphere, and the lithosphere.
Kinds of mountains are fold mountains and block projects.
Fold Mountains: As the molten Centrosphere cooled and contracted, the crust at several places became crumpled, i.e.. full of wrinkles or folds. The elevated parts became mountains-termed as fold mountains and the intervening depressions are known as valleys. The great mountain chains of the world like the Himalayas, the Alps, Andes and the Rockies have been formed by this process.
Block Mountains: If there, are two parallel vertical faults in the earth's crust, the contraction of the inner molten rock to matter causes the parts on either side of the middle block of the rock to subside. This process causes the formation of a Block Mountain. It is also called a Horst. Rift Valley: The sinking down of the part of the earth's crust between two parallel vertical faults fonns a Rift valley. It is U-shaped, whereas a Fold valley is V-shaped. Sudden Movements of the Earth's Crust are noticed during the earthquakes and volcanic eruption. They bring about a change in the earth's surface very quickly. This change of surface level may be brought about by upheaval or subsidence.