Alpide belt

Belt of Eurasian mountain ranges

The Alpide belt or Alpine Himalayan orogenic belt, or more recently and rarely the Tethyan orogenic belt, is a seismic and orogenic belt that includes an array of mountain ranges extending for more than along the southern margin of Eurasia, stretching from Java and Sumatra, through the Indochinese Peninsula, the Himalayas and Transhimalayas, the mountains of Iran, Caucasus, Anatolia, the Mediterranean, and out into the Atlantic. The belt is the result of Mesozoic to Cenozoic to recent closure of the Tethys Ocean and process of collision between the northward moving African, Arabian, and Indian Plates with the Eurasian Plate. The topic began suddenly in the mid 19th century with the evolutionary biologists. The early historical geologists, such as Charles Darwin and Charles Lyell, arranged fossils and layers of sedimentary rock containing them into time periods, of which the framework remains. The late 19th century was a period of synthesis, in which geologists attempted to combine all the detail into the big picture. The first of his type, Eduard Suess, used the term "comparative orography" to refer to his method of comparing mountain ranges, parallel to "comparative anatomy" and "comparative philology. Suess had discovered the zone during his early work on the Alps. He spent the better part of his career following the zone in detail, which he assembled in one ongoing work, das Antlitz der Erde, "The Face of the Earth." Like a human face, the Earth's face has lineaments. Suess's topic was the definition and classification of the lineaments of this zone, which he traced from one end of Eurasia to the other, ending on the east with the Malay Peninsula. Suess looked, as did all geologists, at the strata and content of sedimentary rock, deposited as sediment in the oceanic basins, indurated under the pressure of the depths, and raised later under horizontal pressure into folds of mountain chains. What he added to the field is the study of what he called the "trend lines" or directions of mountains chains. These were to be discovered by examining their strikes, or intersections with the surface. He soon discovered what are known today as convergent plate borders, which are chains of mountains raised by the compression or subduction of one plate under another, but knowledge was not in such a state that he could recognize them as that. He concerned himself instead with the patterns.

The word Alpide is a term first coined in German by Austrian geologist Eduard Suess in his 1883 magnum opus Das Antlitz der Erde and later popularized in English language scientific literature by Turkish geologist and historian A. M. Celâl Şengör in a 1984 paper on the topic. The term adds the suffix ides, derived from the Ancient Greek patronymic/familial suffix ίδης ( ídēs), to the Alps, suggesting a "family" of related orogens. The term belt refers to the fact that the Alpides form a long, mostly unbroken chain of orogens running west to east along the southern edge of Eurasia.

If "Alpide" is taken in Kober's sense to mean the last and current of a collective group of contemporaneous ridges over the entire Tethyan region, then "Alpine orogeny" is used collectively of all the orogenies required to create the Alpides, a definition that is far from the original meanings of Alpide and Alpine, representing a specialized geologic usage.