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From Atlantic to Pacific the Alpine System may be characterized by mobile belts surrounded by the more or less broken up pieces of a mosaic belonging to cratons which either presently exist or may have disappeared by fiagmentation of former large cratonic blocks and ocean spreading. The fmt Tethyan furrows appeared in the Upper Carboniferous. often on the edge of poorly aatonised Hercynian highs. The main Alpine tectonic features are:- Large nappes and overthrusts of two types: - Internal nappes involviq basement slides, often strongly metamorphosed. - External nappes due mainly to gravity gliding, with little or no metamorphism.- Ophiolites are unequally diibuted ahng the system.- Magamatism, especially the acidic type, existsin some places near the main collision areasbut it is much less important than in the Hercynian ranges or the peri-pacifk cordilleras.- The shape of the belts is characterized by complicated girdles and arcs: Gibraltar, Sicily, Westan Alps, Carpathians, Aegean arc. Malaan, Pakistan Ranges, Indonesia and especially Suhwesi etc. . .The surrounding unstable platforms, often with thick marine sedimentary prisms, were folded into intdmediate chains with a “plis de couverture style, often with sliding on salt series (Jura, Provence, Eastern Spain, Saharan Atkas and Tunisian Atlas, Zagros, Pakistan Ranges, c h i o n g Hilss, New Guinea foot hills etc . .). Vcrtical movements have often been neglected in the past but they are now becoming recognised as the principal factor controlling the sedimentation in the three types of Alpine basins In the Mediterranean Sea, as m the Caribbean or in Indonesian marginal bash, relatively recent downm p s have played an essential role since Miocene time and have formed the deep basins which exist today.The Alpine system (sensu lato) is a long mobile belt separating Eurasia from pieces of the former Gondwana Continent, it stretches from the Atlantic Ocean (West of Gibraltar) to the western shores of the Pacific: Irian, Timor, possibly New Caledonia and New Zealand. One may consider a western extension in Caraibs as far as the Venezuelan and Columbian northern cordillera and the southern ranges of Guatemala.Alpine folding was mainly due to the compressional effect of the cratons motion. An important crustal shortening may be inferred from the overthrusted structure: +/- 250 km in western Alps. +/- 500 km in central Himalaya, this shortening is related to subduction processes but we must keep in mind that this term has to be used in the sense defined by AMPFERER (1906-1923, = Verschluckung) and by AMSTUTZ (1951- 1971) and not necessarily with the significatibn of a Benioff type lithospheric sink (cf. TRUMPY 1975).The crustal nature of the alpine zones is very complex, formed by a mosaic of blocks and arcs with a sialic or intermediate crust, associated with troughs of simatic or intermediate nature. The Alpine hiatus strictly speaking, chracterized by nappes and by large oterthsts, is usually separated from cratons by transition zones, unstable shelves where intermediate ranges are generated such as the Saharan Atlas, the Pyrenees-Provence folds, Jura, Caucasus, the Zagros Mountains, the external Pakistan ranges, etc. The unstable belt, between cratons, is generally 1000 to 1500 km wide. The crustal complexity is probably a consequence of upper mantle anomalies, irregular in time and space.We may describe, as a standard, the central end eastern Mediterranean part of the belt: Western Alps, Central and Eastern Alps, Apennines, Carpathians, Dinarides, Balkan, Hellenides and Turkish ranges. They may be divided into two main belts, roughly parallel: the Alpidic and Dinaric Branches.- On the northern side, the Alpidic Branch (Rameau Alpidique) consists from W to E of the Betic Cordillera (south of Spain) and the Balearic Islands, the NE of Corsica, the main part of the Western and Central Alps, the northern fringe of Eastern Alps, the external Carpathians, the Transsylvanian Alps, and the Pontides (Northern part of Turkey).- On the Southern side, the Dinanc Branch (Rameau Dinarique) includes from West to East: Moroccan Rif, Tellian Atlas of Algeria, Northern Tunisia, Northern Sicily, Calabria, The Apennine?, a vqy minor internal part of the Western Alps, the maor part of the Eastern Alps (upper Austroalpine and Carnic zones, part of the Internal Carpathians, the Dinarides, the Hellenides and the Taurides (S Turkey). The difference between both branches is physical, made by separating axial ",massifs", and it is also deduced from paleogeographic comparison.Between the Alpidic and Dinaric branches there is a series of nuclei or ancient blocks called Axial Massifs, or ",Rameau median", or ",Zwischengebirge",. In the Western Mediterranean area, the existence of such axial blocks is inferred from paeogeographic and sedimentologic features but it is concealed now by recent deep sea basins: Algerobalearic Sea, Tyrrhenian Sea. A few remains outcrop in the Central Alps with Insubrian and Orobic basement, in the Eastern Alps the Middle Austro-Alpine units belong to the Median Branch: Niedere Tauern, Silvretta Massif, Oetzal, etc. . .Going eastward, one- finds large axial blocks: tKe Veporides of the Carpathians, part Qf the substratum .of the Transylvanian and Pannonian Basins, the Rhodope Massif, and the Kirsehir and Menderes Massifs in central Turkey (BRU", 1964-1 965, CAIRE 1975). The Alpine instability was initiated at the end of Carboniferous (Moscovian or Pennsylvanian time) on weak zones inherited from the Hercynian orogeny.The Alpidic and Dinaric Branches had different early evolutions (cf. BRUNN 1964 and 1967). After the sudetan phase, several troughs were infilled by fresh water sediments, often coal-bearing during the Upper Carboniferous,. and by continental red beds, very thick in places during the Permian. These furrows correspond to the archaic geosyncline of ELLENBERGER (1968). The following Triassic sediments were of Germanic or .ParaGermanic facies.On the other hand, the Dinaric Branch has just a slight Hercynian discordance (or none at all) with marine Upper Carboniferous and Permian deposits, containing Fusulines, overlain by various facies of Triassic, of a Germanic type in Western parts, of an Alpine or tiansitional type in eastern regions.Between the two archaic geosynclines the Median Branch emerged during the Pennsylvanian: reduced Permian and Triassic beds directly overly crystalline basement of the ",Zwischengebirge.",Since Triassic times, the Alpine Hiatus has revealed itself by a regime of troughs and ridges, irregularly unstable in time and space.In order to understand the situation before the main overthrusting, it is necessary to push back the nappes to their original position, and reconstitute the paleogeography at different phases. Along the Mediterranean part of the Alpine system formation of the troughs was due to distension between the European and African aatons during some part of the Jurassic and perhaps Triassic times. In the Central Asian part we presently see the effects of collision between the Asian craton and Arabic and Indian blocks and there is a discussion on the disappearance of the former Tethyan Ocean existing between Gondwanaland and Eurasia.Main phases of distension or compression which were not of the same age in different places along the Alpine System and in the different zones across the Branches, they correspond to undulation effects with sort of infracrustal waves in both longitudinal and transversal directions.In general, from the most internal part, going outward, one may find the following paleogeographic units:- Central massif or Zwischengebirge.- Eugeosynclinal basin with a thin sialic or intermediate crust or an oceanic floor, covered by deep water.- Miogeosyncline domain with down warped sialic substratum and discontinous trenches and ridges.- Platform edge which may be folded by major tectonics and especially by thelate frontal subsidences. This edge can be more or less transitional, in some places there is a wide zone of intermediate unstable shelf which generated intermediate ranges such as the Jura or the Saharan Atlas.In the most common case, overthrusting corresponds to centrifugal displacements, from the axial zones towards the platforms. We shall see several exceptions.