Armorica (continent)

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Paleogeographic reconstruction at the time of the Middle Devonian . Armorika (Am) is located on the western tip of the Hun super crane

Armorica is the name of a small continent in geological history that existed in the Paleozoic . Today, research tends to see in Armorica rather than a single small continent rather a group of micro-continents or continental crustal blocks, also known as Armorica group or Armorica-Terra Group (Engl. Armorica Terrane Assemblage is called). In the latest paleogeographical reconstructions, the Armorica group is considered to be part of the Hun superterran , which extended far into Asia in the Paleozoic in the eastern continuation of the Armorica group.


In Roman times, Ar (e) morica was the name of the north-western parts of Gaul (roughly equivalent to today's Brittany and Normandy ).


The Armorica group includes the following Central European crustal blocks: the Armorican Massif of Brittany , the Saxothuringian , the Moldanubic of the Moldanubian Terran , the Paleozoic core of the Alps , parts of the Iberian Peninsula, the Hungarian Plain, the Paleozoic Underground of Greece and other areas. These blocks of crust were welded and consolidated to Laurussia during the Variscan Orogeny . Today they are largely covered by younger sediments and some of them were later even included again in a mountain formation, the Alpidic orogeny .

History of the small continent

The area of ​​the small continent Armorica or the smallest continents of the Armorica group was strongly deformed and consolidated in the Cadomian orogeny in the Upper Proterozoic about 650–550 million years ago. Later, before the beginning of the Cambrian, there was profound erosion in these areas. Above this basement lie discordant Lower Cambrian layers, which were only later folded in the Variscan Orogeny and diagenetically modified. At that time, the smallest continents of the Armorica group were still on the northern edge of Gondwana, to the north adjoining western North Africa. After Avalonia broke off from the northern edge of Gondwana , the Rhine Ocean opened up between Avalonia and Gondwana . In the Upper Silurian , the Armorica group broke off as the western part of the Hun superran from Gondwana and drifted north towards Laurussia . The Palaeotethys opened between Armorica (and its continuation to the east, the Asiatic Hunian Terrans) and Gondwana . The Rheic Ocean between Laurussia and Armorica was subducted under Armorica. In the Lower Devonian, smaller crustal blocks broke off from the also consolidated southern edge of Laurussia, and a narrow ocean basin, the Rheno- Hercynian, was created between these crustal blocks and Laurussia . In the Central Devon, Armorica initially collided with these blocks of crust. Gondwana collided with Laurussia in the Upper Carboniferous. Palaeotethys and Rhenohercynian Oceans were subducted . Between Laurussia and Gondwana, the wide folding belt of the Variscides arose.


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