As the relief is formed

The relief of Earth is formed with the participation of two forces: external or exogenous and internal or endogenous. Winds, effect of water, sunlight, chemicals concern the first, the second are the processes happening under earth crust which cause earthquakes, eruptions of volcanoes, emergence of cracks and geysers. In total all these forces create a unique view of the earth's surface.

Instruction

1. The endogenous processes happening in an Earth's mantle under earth crust have much bigger impact on a relief as their force is higher, and results are shown quicker. Earth crust – not a stable and continuous crust on a cloak surface, it has cracks, breaks, holes, certain sites which accumulate at each other. Under it the melted breeds move that causes in certain places of an earthquake – tremors as a result of which on earth crust cracks and shifts of layers are formed. In other cases the magmatic processes lead to eruptions of volcanoes: the lava and fragments of rocks which form wide craters, high mountains or the whole islands is thrown up from the centers.

2. Movements of earth's plates caused serious changes in Earth relief. So, scientists assume that the highest mountains on the planet – the Himalayas – were formed because of collision of Hindustan which was the certain island, and Eurasia. Plate thickness in this place was very thin, as a result folds which continue to grow still easily began to be formed. Also eruptions of hot springs and geysers belong to endogenous processes, but they have smaller impact on a relief. All these external forces can change certain sites of earth crust pretty fast: cases when volcanoes appeared suddenly are known, and in several hours on their place high mountains grew. Movements of earth's plates and change of a relief which are caused by them happen much more slowly, but results turn out more essential.

3. The external processes having influence on a relief are called exogenous. First of all this action of wind and water. Aeration is called gradual destruction of rocks because of air flows, but there is also chemical aeration. In water chemicals which promote faster destruction of breeds can be dissolved. As a result of aeration the whole mountains disappear, and on their place there are flat plains. It is very slow process taking millions of years. Water can seriously influence a relief too, the rivers cut through deep courses, form wide valleys, high rocks and huge gorges. Glaciers form a relief, in Ice Age the ice layers left the mark in many parts of Earth.

Author: «MirrorInfo» Dream Team


Print