Alpine folding - an era in historyformation of the earth's crust. In this era, the world's highest mountain system, the Himalayas, was formed. What characterizes the era? What other mountains of alpine folding exist?
Earth crust folding
В геологии слово «складка» недалеко отходит от its primary value. It denotes a section of the earth's crust in which the rock is “crushed.” Typically, the rock lies horizontal layers. Under the influence of the internal processes of the Earth, its position may change. It flexes or is compressed, overlapping adjacent areas. This phenomenon is called folding.
Wrinkling is uneven.The periods of their appearance and development are named according to geological eras. The most ancient is Archean. She finished forming 1.6 billion years ago. Since then, numerous external processes of the planet have turned it into plains.
After the Archean existed Baikal,Caledonian, Hercynian, Mesozoic folding. The most recent is the alpine folding era. In the history of the formation of the crust, it takes the last 60 million years. The name of the era was first voiced by French geologist Marcel Bertrand in 1886.
Alpine folding: period characteristic
The epoch can be divided into two periods.In the first in the earth's surface deflections actively appeared. Gradually they were filled with lava and sediment. The elevation of the cortex was small and very local. The second stage was more intense. Various geodynamic processes contributed to the formation of mountains.
Alpine folding formed a largeSome of the largest modern mountain systems that are included in the Mediterranean fold belt and the Pacific volcanic ring. Thus, folding forms two large areas with mountain ranges and volcanoes. They are part of the youngest mountains of the planet and differ in climatic zones, as well as heights.
The epoch is not over yet, and the mountains continueform now. This is evidenced by seismic and volcanic activity in various regions of the Earth. Folded area is not solid. The ridges are often interrupted by depressions (for example, the Fergana Depression), in some of them seas (Black, Caspian, Mediterranean) have formed.
Mediterranean belt
Alpine folding mountain systems thatbelong to the alpine-himalayan belt, stretched in the latitudinal direction. They almost completely cross Eurasia. They begin in North Africa, pass through the Mediterranean, Black and Caspian Seas, stretch across the Himalayas to the islands of Indochina and Indonesia.
Alpine folding mountains include the Apennines,Dinars, the Carpathians, the Alps, the Balkans, the Atlas, the Caucasus, Burma, the Himalayas, the Pamirs, etc. They all differ in their appearance and height. For example, the Carpathian Mountains are medium-high and have smooth outlines. They are covered with forests, alpine and subalpine vegetation. The Crimean mountains, unlike them, are steeper and more rocky. They are covered with more mean steppe and forest-steppe vegetation.
The highest mountain system is the Himalayas.They are located within 7 countries, including Tibet. The mountains stretch for 2,400 kilometers in length, and their average heights reach 6 kilometers. The highest point is Mount Everest with an altitude of 8848 kilometers.
Pacific Ring of Fire
Alpine folding is also associated with the formationPacific Ring of Fire. It includes mountain ranges and depressions that adjoin them. Located volcanic ring on the perimeter of the Pacific Ocean.
Оно охватывает Камчатку, Курильские и Японские Islands, Philippines, Antarctica, New Zealand and New Guinea on the west coast. On the east coast of the ocean, it includes the Andes, the Cordillera, the Aleutian Islands and the Tierra del Fuego archipelago.
The name "ring of fire" this area deserveddue to the fact that most volcanoes of the planet are located here. About 330 of them are active. In addition to eruptions, the greatest number of earthquakes occur within the Pacific Belt.
Part of the ring is the longest mountain system of the planet - the Cordillera. They cross 10 countries in North and South America. The length of the mountain range is 18 thousand kilometers.
