Opening the world map, you can see countless mountain ranges stretching around the world, either across east and west, or vertically across north and south. They use their magnificent bodies to shape mountains and rivers, affect the distribution of climate and organisms, and participate in interactions between the earth's circles. Numerous mountains have also endowed mankind with abundant mineral and forestry resources and influenced human civilization.
Mountains are continuous mountains distributed in strips along certain structural lines. The numerous mountain ranges distributed on the earth intuitively demonstrate the active and extensive movement of the earth. In the eyes of geologists, these mountainous areas are also called orogenic belts. They are areas where dynamic forces in the earth's interior were once particularly strong. Those areas that are huge and have strong effects are often the edges of plates.
As long as two adjacent plates move relative to each other, it often brings about energy release and material reorganization. The towering mountains are the product of the folding, compression and piling of plate edges under the impetus of this energy. In real life, we can easily see a similar phenomenon: when two cars traveling at relatively high speeds collide, the front of the car often undergoes severe squeezing and deformation. You can also do a simple experiment: squeeze two flat plasticine pieces against each other hard, and the two plasticine pieces will stick together firmly, and the bonded parts will be mixed into a ball and stacked thickly. The formation of mountains is similar, except that the protagonists are replaced by huge plates on the earth's surface.
According to the division of French geologist Savile Le Pichon, the earth's plate can be divided into six major plates. The interior of the large plate can be divided into multiple small plates. Around the same plate, there are also multiple edge zones that are in contact with other plates. This is the direct reason why the earth has so many mountain ranges.
Although the interactions between plates are complex and changeable, generally speaking, they can be divided into three categories. The first type of orogenic belt comes from areas where plates run away from each other. The movement of plates against each other often tears huge rifts in the earth. Magma overflows from the mantle, fills the rift and accumulates upward, eventually forming a huge chain of fissured volcanoes. The mid-ocean ridge system deep in the ocean floor is typical of such orogenic belts. They span the world and connect the four oceans, making them the largest mountain system on earth.
The second type of orogenic belt comes from areas where plates move towards each other. One is due to the collision of an ocean plate and a continental plate, and the other is the collision of two continental plates. The first type is due to the high density of the ocean plates. During the collision, the ocean plates are inserted downward, thus forming an island arc volcanic chain. The continuous superposition of volcanic chains will in turn accumulate on the margin of the continent to form an accretive orogenic belt. However, in the collision between continental plates, due to the similar density of the two, no one allowed the other. Under the huge energy, the plate edges were violently deformed and folded, and finally formed a towering large-scale mountain-plateau system. Today's Alps-Himalayan orogenic belt is an example of such a land-land collision orogenic belt. Since 71 million years ago, the Indian Plate has gradually collided with the Eurasian Plate, forming the Himalayas.
The third type of orogenic belt is created by friction between parallel plates. When we stack three coins together and rub the outer two repeatedly, the middle one will bulge out. Mountains are developed in a similar way in fault zones on plate margins, but the number and scale of these mountains are much smaller than the first two types.
Although mountain ranges generally come from collisions and deformations at plate margins, some unique mountain ranges can also be formed within the plates, which geologists call intracontinental orogenic belts. It is generally believed that the intracontinental orogenic belt is controlled by faults within the plate, or is influenced by long-range waves from collisions on the plate margins.