scholarly journals Late-devonian sakhara dunite-clinopiroxenite-gabbro complex (East Magnitogorsk zone, South Urals): petrological-mineralogical features and geodynamic setting

2021 ◽  
Vol 7 ◽  
pp. 40-53
Author(s):  
T.N. Surin

The relevance of the work is caused by necessary regional analysis of magmatic evolution of the East Magnitogorsk belt and refnement of ideas on geodynamics of the South Urals. The geology and petrochemical-mineralogical features of the Sakhara dunite-clinopyroxenite-gabbro complex in the South Urals are characterized in the paper. Its late Frasnian age is substantiated. The composition of olivine, clinopyroxene and chromite in rocks of the complex are determined. The restite nature of dunites is proved. It is shown that rocks of the complex are similar to those of the Urals platinum belt and belong to Ural-Alaskan type. It is concluded that the complex formed in island-arc geodynamic setting and in the beginning of the formation of a mature island arc. The location of massifs of the complex is an additional argument in favor of a western dip (in the present-day coordinates) of a subduction paleozone at the moment of its formation. Crystallization diferentiation was a leading mechanism of petrogenesis of rocks of the complex.

2020 ◽  
Vol 14 (4) ◽  
pp. 675-687
Author(s):  
Marina Nikolaevna Potemkina ◽  
Tatiana Grigoryevna Pashkovskaya

The mythologization of history and presence of unexplored aspects in the history of Estonia during the Second World War period prevent the establishing good-neighbourly relations and partnership between Russia and Estonia. Estonians’ life in the evacuation in the Urals is a ‘blank spot’ in the historiography. The article is based on the archival documents and sheds light on the situation of people evacuated from Estonia to the South Urals in the period 1941-1944. The quantitative and qualitative analysis of the evacuees’ composition is provided. The difficulties of Estonians’ adaptation in the Soviet rear are elicited. It is concluded that Estonians had the same problems as all evacuees in the USSR. Besides, their situation was worsened by the linguistic barrier, the level of poverty in the Urals in comparison with Estonia, impossibility to lead traditional work, the ignorance of the Soviet laws, the abhorrence of the Soviet system among parts of the evacuees. The problems arising between the locals and Estonian evacuees were caused by the differences in everyday practices and historical and cultural traditions, and not the national or religious identity. The short-term stay of Estonians in the Urals could not lead to cultural or linguistic assimilation.


2016 ◽  
pp. 37-54
Author(s):  
L. M. Ishbirdina ◽  
N. I. Fedorov ◽  
A. A. Muldashev

The geographical and phytocoenotic areas of the endemic of the Southern Urals Delphinium uralense that is a relic species of the ancient Pleistocene steppe were studied. Species is listed in the Red book of the Russian Federation (2008) and the Red Book of the Republic of Bashkortostan (2011). The main part of the geographical area of the investigated species is limited by the Zilair plateau located in the south-western tip of the Ural Mountains, within the Urals fold-block surface. The phytocoenotic area of this species includes the xerophytic communities referring to 2 classes, 3 orders, 4 alliances, 1 suballiance, 2 associations, 1 subassociation, 1 variantand 4 non-ranking communities The formation of the unique complex of xerophytic oak-larch sparse forests and rocky steppes in the southern Urals is linked with the occurrence of the mountainous steppe with larch groves, which were the remnants of the xerophytic mountain landscape —“Pleistocene floristic complex” (Igoshina, 1961, 1963). The enrichment the floristic composition of the complex took place in the late Pleistocene due to following facts: the appearance of rock and mountain-steppe Asian relict species (Ryabinina, 1993), the migration of Eastern Siberian elements to the West, the movement of European species to the East, the formation of the Urals endemic floristic races (Krasheninnikov, 1939). Later, in the Holocene, the Pleistocene floristic complex was enriched by some species of broad-leaved forests (including oak Quercus robur), the penetration ofthe south richsteppe flora, and replenishment of the floristic complex by the Pontic and Sarmatic species (Igoshina, 1961). As a result of mentioned above processes a unique complex of xerophytic rocky mountain steppes and of sparse oak and larch elfin woodswas formed in the Zilair plateau.


2021 ◽  
Vol 12 (2) ◽  
pp. 365-391 ◽  
Author(s):  
A. M. Kosarev ◽  
A. G. Vladimirov ◽  
A. I. Khanchuk ◽  
D. N. Salikhov ◽  
V. B. Kholodnov ◽  
...  

The oceanic stage in the history of the South Urals completed in the Ordovician – Early Silurian. The Ordovician through Devonian events in the region included the formation of an island arc in the East Ural zone from the Middle Ordovician to Silurian; westward motion of the subduction zone in the Late Silurian – Early Devonian and the origin of a trench along the Main Ural Fault and the Uraltau Uplift; volcanic eruptions and intrusions in the Magnitogorsk island arc system in the Devonian. The Middle-Late Paleozoic geodynamic evolution of uralides and altaides consisted in successive alternation of subduction and collisional settings at the continent-ocean transition. The greatest portion of volcanism in the major Magnitogorsk zone was associated with subduction and correlated in age and patterns of massive sulfide mineralization (VMS) with Early – Middle Devonian ore-forming events in Rudny Altai. Within-plate volcanism at the onset of volcanic cycles records the Early (D1e2) and Middle (D2ef2) Devonian slab break off. The volcanic cycles produced, respectively, the Buribay and Upper Tanalyk complexes with VMS mineralization in the Late Emsian; the Karamalytash complex and its age equivalents in the Late Eifelian – Early Givetian, as well as the lower Ulutau Formation in the Givetian. Slab break off in the Late Devonian – Early Carboniferous obstructed the Magnitogorsk island arc and supported asthenospheric diapirism. A new subduction zone dipping westward and the Aleksandrovka island arc formed in the Late Devonian – Early Carboniferous. The Early Carboniferous collision and another event of obstructed subduction led to a transform margin setting corresponding to postcollisional relative sliding of plates that produced another slab tear. Postcollisional magmatism appears as alkaline gabbro-granitic intrusives with related rich Ti-magnetite mineralization (C1). Transform faulting persisted in the Middle Carboniferous through Permian, when the continent of Eurasia completed its consolidation. The respective metallogenic events included formation of Cu-Ni picritic dolerites (C2–3), as well as large-scale gold and Mo-W deposits in granites (P1–2).


2017 ◽  
Vol 14 (1-4) ◽  
pp. 319-347 ◽  
Author(s):  
Svetlana V. Nikolaeva ◽  
Elena I. Kulagina ◽  
Elena N. Gorozhanina ◽  
Alexander S. Alekseev ◽  
Vera A. Konovalova

2020 ◽  
Vol 0 (4) ◽  
pp. 89-95
Author(s):  
F.A. KRYZHANOVSKY ◽  

The article examines the main publications covering the centuries-old history of the Catholic Church in the lands of modern Bashkortostan, as well as partly affecting the interaction of local Catholic communities with coreligionists from other cities located in the South Urals, as well as in the Middle Volga region. Unfortunately, there are quite a few special studies on the history of this Christian denomination in our republic. Many works, in one way or another related to this issue, are of a general nature and contain a schematic listing of factual information, or are more devoted to the history of national communities, for which this religion is, to a certain extent, one of the most important elements of traditional ethnic culture. Here it is necessary to note, first of all, publications on the history of the Polish and German diaspora, which provide information about the participation of representatives of these communities in the creation of Catholic parishes and public associations associated with charity and education. At the same time, the significance of the confessional aspect is to a much lesser extent revealed in works on the history of Latvian immigrants from Latgale, Belarusians and Ukrainians from Volyn and Eastern Galicia, who, due to various circumstances, left their homes during the First World War, as well as other Catholic emigrants from Central and Western Europe, located in the Ufa province at the beginning of the XX century. In some articles on demography and striking features of social stratification, one can find indirect references to the presence of Catholics, but this information only It is noteworthy that most publications indicate the middle of the 17th century as the earliest dating of the appearance of believing Catholics in the South Urals, and evidence of missionary trips to the Eastern Hungarians during the 13th-15th centuries allows us to make hypothetical assumptions about their role in the life of the local religious community. It can be noted that the presence of a certain part of Catholics on the territory of Bashkiria during the 16th20th centuries. was associated with forced migration due to the fact that, as a result of military clashes, some of them were captured, as well as due to participation in activities that conflicted with the interests of the Russian leadership are considered, with a few exceptions, only in the context of the problem of the origin of the Bashkir people, most likely due to the modest results of the preaching.


2003 ◽  
pp. 62-80 ◽  
Author(s):  
S. M. Yamalov ◽  
A. A. Filinov ◽  
A. I. Solomeshch

The five new steppe-meadow associations are des­cribed in the South Urals. They refer to the class Molinio-Arrhenatheretea R. Tx. 1937 em. R. Tx. 1970, ord. Galietalia veri Mirkin et Naumova 1986, all. Trifolion montani Naumova 1986, and the suball. Trifolienion montani Mirkin et Naumova 1986. The communities of these associations are typical of their richness in species, including such rare and endangered ones as Dianthus acicularis, Stipa korshinskyi, Stipa sareptana, Stipa zalesski, Stipa pennata, Stipa da­syphylla, Tulipa biebersteiniana etc., the fact which makes for their significant value for nature protection purposes.


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