Geology

Europe is distinguished by great complexity and a high degree of knowledge of the geological structure. Vast spaces are located within the East European (Russian), or European, platform with a folded foundation of Precambrian age. In the east, within the Russian Plate, where it is deeply submerged, and in the eastern part of the Baltic Shield, where it protrudes to the surface, the foundation is composed of Archean and Early Proterozoic rocks. Late Proterozoic metamorphic rocks are widely developed in the west (south of Scandinavia, Denmark and Great Britain). After the foundation was consolidated over the past 1200-1600 million years, some parts of the platform were subjected to prolonged diving, covered by seas and lagoons. This led to the formation of a powerful platform cover, which consists of sedimentary series of the end of the Proterozoic (Iotnium, Riphean), sandy-clay strata of the Cambrian, Ordovician, Silurian limestone, red-colored, saline and calcareous rocks of the Devonian, thick continental strata (with coal-bearing series) of coal. Permian and Triassic age. Late Triassic, Jurassic, Cretaceous, as well as Paleogene and Neogene deposits, filling deep depressions mainly along the edges of the platform, sometimes reach several km of thickness (Hamburg Depression, about 6 km). In some tectonically active periods (in the Vendian, Devonian, Permian and partially Jurassic) volcanic activity was manifested within the platform, with which the formation of basalts and other effusive rocks was associated. To the north from the East European platform, occupying the continental northern shelf (from Franz Josef Land to the Pechora Lowland), the Precambrian platform of the Barents Sea extends. An analogous ancient platform (Eria) forms the edge of the shelf to the north from the British Isles. Iceland and Fr. Jan Mayen are heterogeneous volcanic uplifts that arose in the Cenozoic over the northern part of the Mid-Atlantic Range

The northeastern part of E. (Timan Ridge, Pechora Lowland, northern margin of the Kola Peninsula), composed of Riphean shale series, belongs to the Baikal folding zone.

Via S.-Z. the mainland (from Svalbard to the north through Bear Island, the Scandinavian mountains, the north and west islands of Great Britain and the island of Ireland) extends the Caledonian folded system, which arose from deep geosynclinal troughs of the ancient Paleozoic and Pre-Paleozoic times. It developed powerful volcanic and sedimentary strata of Cambrian, Ordovician and Silurian, the section of which ends with powerful Devonian red-colored molasses. This system is characterized by an abundance of magmatic formations and complex folding. In Scotland and Norway, knuckles are known with an amplitude of horizontal movement of up to 100-120 km; in Scotland they are directed towards the northwest, towards the Eria platform, in Norway — towards the southwest, towards the Baltic shield.

To the south of the Caledonides, speaking on the surface on the Iberian Peninsula, in the Central and Armorican massifs of France, in South Wales, the Ardennes, Vosges, the Black Forest, the Harz Mountains, the Ore Mountains, the Bohemian massif, the Sudetenland, Silesia and Sventoškyski mountains, partially covered Hercynian structures a cover of slightly disturbed sedimentary strata of the Mesozoic and Cenozoic. Within the Hercynides, a large number of ancient massifs (Bohemian, Central French, etc.) stand out, composed mainly of Precambrian metamorphic strata. Around these ancient nuclei, there are extended powerful ev- and myogeosynclinal zones. In the areas of Varis folding, large horizontal and gentle thrusts are developed (Ardennes, Iberian Peninsula), as well as complex dome-shaped, sometimes fan-shaped folds.

Hercynides also include the folded structures of the Urals and Novaya Zemlya, adjacent to the European platform from the east. The Paleozoic folded strata of the Urals are pushed to the West. In V. they are penetrated by powerful intrusions of hyperbasites and granitoids. The folded system of the Urals consists of a series of parallel anticlinal uplifts and synclinal troughs in the eastern part of the mountainous country that are eugeosynclinal, and in the west, myogeosynclinal in structure.

Along the boundaries with ancient platforms, as a rule, there are edge troughs (the large «coal channel» of France — Belgium, the Ural trough) filled with coal, oil and saline molasses. From east, the East European platform is limited to the Paleozoic folded region of the Urals.

Mountain constructions of the south of E. (Andalusian mountains, Apennines, Alps, Carpathians, mountains of the Balkan Peninsula, Crimea, etc.) belong to the Alpine geosynclinal (folded) region. The northern part of the alpine geosynclinal troughs superimposed on the Paleozoic folded structures Western and Southern E. In these zones, mainly shale, flysch and powerful carbonate series were formed that compose the Alps and Carpathians. Here magmatism was weakly manifested; During the alpine tectonic era, powerful covers and deep marginal troughs arose. The southern part of the Alpine folded region arose on the site of the previously divided Alpine movements of the Epibaikal platform, which encircled the Paleozoic in the form of an extensive mobile shelf from the North African-Arabian Precambrian platform. Many stable ancient blocks have been preserved here — median massifs and traces of widely developed alpine magmatism (in the form of hyperbasites).

Within the Alpine folded region, peculiar depressions arose, characterized by the close to oceanic type of structure of the earth’s crust (partially the depression of the southern Caspian, Black Sea, Tyrrhenian, etc.). According to geophysical studies, the “granite” layer is greatly reduced (or completely absent) and the earth’s crust as a whole has a thickness of about 20 — 30 km.

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