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25-740: The extension is still ongoing. The current southern Aegean is one of the most rapidly deforming regions of the Himalayan-Alpine mountain belt. It is approximately 450 km long and 20 km to 40 km wide and runs from the Isthmus of Corinth on the Greek mainland to the Bodrum peninsula on the Turkish mainland . The original proponent of a convergent boundary between Africa and Eurasia, who devised Tethys Ocean and Gondwana land for

50-622: 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

75-670: A consequence of the formation of the North Atlantic Ocean. As Tethys closed, Gondwana pushed up mountain ranges on the southern margin of Eurasia. The Alpide belt is a concept from modern historical geology , the study in geologic time of the events that shaped the surface of the Earth. 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

100-829: A time of faulting to adjust to the current pressures. In the Pliocene, the extension had been NE–SW causing "normal high angle faults trending NW–SE". In the Quaternary, the direction of extension changed to N–S with faults trending E–W. The type is predominantly strike-slip. The active portion of the South Aegean Volcanic Arc comprises a number of dormant and historically active volcanoes, including Sousaki , Aegina , Methana , Milos , Santorini and Kolumbo , Kos , Nisyros and Yali , and Akyarlar. Of these, only Santorini, Kolumbo, and Nisyros have either erupted or shown any significant evidence of unrest during

125-679: Is a dormant volcano and modern solfatara field in northeastern Corinthia , Greece , at the northwest end of the South Aegean Volcanic Arc . The volcano was active during the Pliocene and early Quaternary periods of the Earth's geological history. There is still significant solfataric activity at this location. The volcano erupted dacite lava. The geothermal system releases about 1 megagram per day of gases at 42 °C, 90% CO 2 and < 1% each of CH 4 and H 2 S . The earthquakes of 1997 of 3-4 R had as

150-573: Is a two-phase Alpine Orogeny. In phase 1 ( Cretaceous ) the Tethys sea floor after depositing its Cimmerian passenger against Eurasia went on to dip beneath Cimmeria-Eurasia raising the inner (eastern) Hellenides ( Pindus range) and the Anatolides. Phase 2 is the arrival of another terrane, the Adriatic, or Apulian, Plate from the southwest, dipping under Cimmeria-Eurasia and raising its margin into

175-716: The Atlantic . It includes, from west to east, the major ranges of the Atlas Mountains , the Alps , the Caucasus Mountains , Alborz , Hindu Kush , Karakoram , and the Himalayas . It is the second most seismically active region in the world, after the circum-Pacific belt (the Ring of Fire ), with 17% of the world's largest earthquakes. The belt is the result of Mesozoic -to- Cenozoic -to-recent closure of

200-592: The Tethys Ocean and process of collision between the northward-moving African , Arabian , and Indian plates with the Eurasian plate . Each collision results in a convergent boundary , a topic covered in plate tectonics . The approximate alignment of so many convergent boundaries trending east to west, first noticed by the Austrian geologist Eduard Suess , suggests that once many plates were one plate, and

225-733: The Alpide belt along the south and west from Sumatra , Java and the Lesser Sunda Islands ( Bali , Flores , and Timor ). The 2004 Indian Ocean earthquake just off the coast of Sumatra was located within the Alpide belt. 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

250-669: The Alpine-Cimmerian-Eurasian plate, dove under it in the ancestor of the Hellenic Trench . The result was the raising of the forearc and the "exhumation" of Peloponnesus and Crete. It began to migrate to the south by back-arc extension, jutting out into the Mesogean Sea and becoming arcuate. From there the geologic story becomes more familiar, being mentioned above. The Quaternary in the Aegean has been

275-775: The Dinarides and outer Hellenides in the Eocene and Oligocene . The geologic stage was set for the latest orogenic zone, developing in the Miocene and Pliocene . It is customary to regard Tethys as gone, replaced by the Mesogean sea, plate, and orogeny, which were transitional to the Mediterranean. The Mesogean Plate is of Gondwana; that is, the predecessor of the African plate. This plate, moving north as Gondwana approached

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300-589: The Tethyan orogenic belt , is a seismic and orogenic belt that includes an array of mountain ranges extending for more than 15,000 kilometres (9,300 mi) 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

325-558: The accumulation of orogenies in successive waves of advance. Not all the parallel chains derive from the same period or the same rocks. From the present, there is a virtual advance with a virtual resulting chain, but the chain is mainly a composite of successive chains. The mountains of Greece, or Hellenides (viewed as a singular collective thing) appear to have had a singular origin, superficially named "the Hellenic orogeny ". These are only terms of convenience to distinguish "Hellenic" from

350-518: The collision formed one subduction zone, which was oceanic, subducting the floor of Tethys. Suess called the single continent Gondwana , after some rock formations in India, then part of the supercontinent of Gondwana, which had earlier divided from another supercontinent, Laurasia , and was now pushing its way back. Eurasia descends from Laurasia, the Laurentia part having split away to the west as

375-544: The drift theory won the field just as suddenly as had the evolutionist. The concepts and language of the comparative graphists were kept with some modification, but were explained in new ways. The author of the concept of a trans-Eurasian zone of subsidence , which he called Tethys , was Eduard Suess . He knew it had been a subsidence because it expressed deposits of the Mesozoic , now indurated into layers and raised into highlands by compressional force. Suess had discovered

400-542: 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

425-458: 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. His work preceded plate tectonics and continental drift. This pre-tectonic phase lasted until about 1950, when

450-427: 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. Sousaki volcano Sousaki ( Greek : Σουσάκι ; Modern Greek pronunciation: [suˈsaci] )

475-462: The mountains of other countries. They are accumulated mountain chains resulting from accumulated orogenies over time. Currently, three "waves", of orogenic activity can be distinguished, resulting in three "orogenic belts". Preceding the first wave, the supercontinent, Pangaea , had already broken into Laurasia (a continuous band of Eurasia and the Americas), and Gondwana (all the rest). Between

500-620: The ocean to lodge against Eurasia, forming Cimmeria-Eurasia. The existing Cimmerides (named after the mountains of Crimea) account for the northernmost chains of the Alpides. Sometimes they are called the Hunic terranes , after the land of the Huns . They cover the Black Sea region, the northern Aegean, and the eastern part of the Balkans. Their earliest date is the "pre- Late Jurassic ". Subsequent

525-493: The past 100 years. One of the most noted volcanic eruptions from this arc occurred on the island of Santorini in the 2nd millennium BC ; during the catastrophic volcanic eruption of Santorini , the Bronze Age city of Akrotiri was destroyed, with archaeological remains becoming well preserved under the volcanic ash. Alpide Belt The Alpide belt or Alpine-Himalayan orogenic belt , or more recently and rarely

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550-468: The purpose, and invented the -ides suffix, Eduard Suess , imagined a single great closure of Gondwana land on Eurasia, wrinkling up a mountain belt, the Altaides, that stretched from sea to sea. The simplicity and the name did not survive further scrutiny of the rocks. The mountain chain, subsequently the non-Suessian Alpides (he had his own Alpides, which amounted to the western Altaides), turned out to be

575-492: 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. Indonesia lies between the Pacific Ring of Fire along the northeastern islands adjacent to and including New Guinea and

600-427: The two of them was Paleo-Tethys Ocean . The break-up had been caused by shifting currents in the mantle . A different location of an upwelling plume placed a divergent boundary in a new place, in this case across the north and east of Gondwana. The Cimmeria terrane began to separate from Gondwana, closing Palaeo-Tethys in front of it and opening Neo-Tethys, or just plain Tethys, behind it. Cimmeria voyaged across

625-405: 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

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