Variscan orogenic belt, also called Hercynian orogenic belt, series of mountain ranges that developed during a span of time extending from 370 million to 290 million years ago—during the Devonian Period (which occurred about 419 million to 359 million years ago), the Carboniferous Period (359 million to 299 million years ago), and the early Permian Period (299 million to about 252 million years ago)—as a result of the collision between Africa and a North American–North European continent. The Variscan orogenic belt extends in western Europe for more than 3,000 km (1,860 miles) from Portugal, Ireland, and England in the west through Spain, France (Brittany, Massif Central, Vosges, and Corsica), and Germany (Black Forest, Harz) to the Czech Republic in the Bohemian Massif. The belt contains many rocks and structures that indicate that its formation was a result of seafloor spreading, subduction of oceanic crust, and plate collision. It has a sinuous outcrop caused by collisional indentation of one block into another. Crustal thickening led to uplift, erosion, and extensional collapse of the central part of the belt in the Massif Central and Bohemian Massif and thus to formation of coal-bearing basins in the Carboniferous Period. The southern part of the belt was extensively deformed by the collision tectonics that gave rise to the Alps and Pyrenees, and it was dismembered by the opening of the western Mediterranean basins and the Bay of Biscay.
Learn More in these related Britannica articles:
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France: The Hercynian massifsThe physical structure of France is dominated by a group of ancient mountains in the shape of a gigantic V, the sides of which form the two branches of Hercynian folding that took place between 345 and 225 million years ago. The eastern…
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Europe: Hercynian orogenic beltThe Hercynian, or Variscan, orogenic belt evolved during the Devonian and Carboniferous periods, from about 419 to 299 million years ago. The belt extends from Portugal and western Spain, southwestern Ireland, and southwestern England in the west through the Ardennes, France (…
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Germany: Land…ago) an earlier mountain chain—the Hercynian, or Variscan, mountains—had crossed Europe in the area of the Central German Uplands. Yet the forces of erosion were sufficient to reduce these mountains to almost level surfaces, on which a series of secondary sedimentary rocks of Permian to Jurassic age (about 300 to…
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Spain: Relief…is composed of ancient (Hercynian) rocks; geologists refer to this Hercynian block as the Meseta Central. It constitutes a relatively stable platform around which younger sediments accumulated, especially on the Mediterranean side. In due course these sediments were pushed by major earth movements into mountain ranges. The term
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Pyrenees: Geology…by the present-day Pyrenees (
see Hercynian orogenic belt). The remnants of the Variscan orogeny include the Massif Central in France and the Meseta Central in Spain. Although these other massifs have had a comparatively quiet history of internal deformation, or tectonism, since their emergence, the Pyrenean block was submerged in…
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- Appalachian orogenic belt
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- Europe
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- Germany
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