scholarly journals Paleomagnetism of the Early-Middle Riphean intrusions from the Bashkirian meganticlinorium (the Southern Urals): Implications for the paleotectonic reconstructions of the East European сraton

2019 ◽  
Vol 1 ◽  
Author(s):  
A.V. Latyshev ◽  
◽  
M.B. Anosova ◽  
А.О. Khotylev ◽  
◽  
...  
Keyword(s):  
Southern Urals ◽  
The Southern Urals ◽  
East European ◽  
Paleotectonic Reconstructions

Relative movements of the Bashkirian megazone blocks(the South Urals) according to paleomagnetic data.

2021 ◽  
Author(s):  
Maiia Anosova ◽  
Anton Latyshev ◽  
Alexey Khotylev
Keyword(s):  
Thin Sheet ◽  
Southern Urals ◽  
East European Craton ◽  
Late Paleozoic ◽  
South Urals ◽  
The Southern Urals ◽  
East European ◽  
Northern Regions ◽  
Middle Paleozoic ◽  
Southern Central

<p>     The research object is magmatic bodies from the southern, central and northern parts of the Bashkirian megazone (the Southern Urals, meridian length of the Bashkirian megazone - 300 km). Most of the study intrusions have the Riphean age. In the Riphean the Bashkirian megazone was part of the East European craton. And in the Late Paleozoic rocks of the Bashkirian megazone were involved in the collision process. The formation of most studies bodies is associated with the Mashak magmatic event (the Riphean), which marks the collapse of the super-continent Nuna.</p><p>     The Middle Paleozoic component was isolated in 28 bodies. Probably it is the secondary component, that is widespread on the Southern Urals and has been repeatedly identified by other researchers. Directions comparison from different districts showed that there was a rotation of the southern, northern and central blocks of Bashkirian megazone relative to each other during the Late Paleozoic collision. At the same time, paleomagnetic directions from the northern regions (which are about 40-50 km apart from each other) statistically coincide or differ not so much. Which means that they were stable or relatively stable.</p><p>     Besides, the Riphean component was isolated and the paleomagnetic pole for the boundary of the Lower and Middle Riphean of the East European Craton (1349+/-11 Ma) is calculated from 8 thin sheet intrusions. Plat=8.4; Plong=162.4; A95=4.1.</p>

scholarly journals Subduction, collision and plumes in the epoch of the Late Paleozoic magmatism of the Magnitogorsk zone (the Southern Urals)

LITOSFERA ◽  
2019 ◽  
pp. 191-208
Author(s):  
D. N. Salikhov ◽  
V. V. Kholodnov ◽  
V. N. Puchkov ◽  
I. R. Rakhimov
Keyword(s):  
Late Phase ◽  
Active Continental Margin ◽  
Southern Urals ◽  
Island Arc ◽  
Late Paleozoic ◽  
Time Interval ◽  
Geochemical Type ◽  
The Southern Urals ◽  
European Continent ◽  
East European

Subject. A systematization of Late-Paleozoic magmatic formations of the Magnitogorsk zone of the Southern Urals in the process of an accretion of the Magnitogorsk paleoarc to the margin of the East European continent (EEC) with formation in Famenian and Carboniferous active continent margin of South-Uralian accretionary-collisional belt was given in the work. Materials and methods. A generalization of published and manuscript materials characterizing magmatism and ore-mineralization of Magnitogorsk zone for the Devonian-Carboniferous-Permian time carried out, additional investigations of chemical composition of rocks (XRF, ISP-MS) characterizing process of accretion, subduction and plume activity, microelement distribution in them was made, the composition of rock-forming and accessory minerals (EPMA) was studied. Results. It is found that the South-Uralian accretionary-collisional belt was beginning to form in the late phase of the development of the Magnitogorsk island arc in the process its collision with EEC margin with formation in the Frasnian and Carboniferous of active continental margin. The products of Late-island-arc volcanism are represented by the porphyrite formation and in the eastern frame of the arc - by subalkaline monzonite-shoshonite-latite volcanic-intrusive association with intermediate characteristics between the subductional and interplate formations. Synchronously with them, in the backarc setting, picrite and meymechite volcanics − derivatives of a mantle plume are formed. In process of substitution of tectonic-magmatic regime from island-arc to margin-continental intraplate-type mantle series were forming. During this period, hot asthenospheric diapirs (plumes) were rising to the bottom of new-formed (accreted) margin-continental lithosphere. Along with the magmatic associations of intraplate type and rock series of intermediate geochemical type, this geodynamic situation in the Southern Urals is characterized by a presence of great volumes of mantle-crust granitoids of gabbro-tonalite-granodiorite-granite type, that were formed with a manifold manifestation of anatexis in a time interval of 365-290 Ma. Conclusion. On the whole the originality of Magnitogorsk zone geological history in the Devonian and Carboniferous, peculiarities of magmatic complexes formed here due to various geodynamic settings, are making this zone an extraordinary interesting and important object to study of processes of plume-lithosheric and mantle-crust interaction.

Magnetic evidence for the geometry and evolution of the eastern margin of the East European Craton in the Southern Urals

2000 ◽  
Vol 320 (1) ◽  
pp. 31-44 ◽  
Author(s):  
C Ayala ◽  
G.S Kimbell ◽  
D Brown ◽  
P Ayarza ◽  
Y.P Menshikov
Keyword(s):  
Southern Urals ◽  
East European Craton ◽  
The Southern Urals ◽  
East European ◽  
Eastern Margin

Prospects of paleomagnetic studies of the Riphean intrusive bodies of the Bashkirian megazone (Southern Urals)

2020 ◽  
Author(s):  
Maiia Anosova ◽  
Anton Latyshev ◽  
Alexey Khotylev
Keyword(s):  
Sedimentary Rocks ◽  
Southern Urals ◽  
East European Craton ◽  
Late Paleozoic ◽  
The Southern Urals ◽  
East European ◽  
High Temperature Component ◽  
New Information ◽  
Temperature Component ◽  
Tectonic Dislocations

<p>         The studied objects are located in the core of the Bashkirian megazone and related to the Riphean stage of rift magmatism of the East European craton. Paleomagnetic studies of the Bashkirian megazone intrusive bodies can be a source of new information on the East European platform position in the Riphean, as well as on the process of remagnetization during the Late Paleozoic folding on the Southern Urals. At this moment, 42 thin basic intrusions and the Main Bakal dyke were investigated.</p><p>         According to the results of our previous paleomagnetic studies two remanence components were isolated in Bashkirian megazone intrusions. First, the primary remanence component of Middle Riphean age was isolated in 8 thin bodies. Pole for the boundary of the Early and Middle Riphean of the East European Craton was calculated from high-temperature component of remanence of 8 sheet intrusions. This pole is close to the known paleomagnetic poles of East European craton for close ages and agrees with U-Pb age of one of the studied bodies (1349 ± 11 Ma). Also, arguments in favor of the primary origin of the remanence and the absence of significant tectonic dislocations in the sampling area are discussed. In other 4 intrusive bodies, paleomagnetic directions that are close but slightly different from the Middle Riphean directions were found. Second, the Late Paleozoic directions were found in the studied objects. These directions are widespread in the Bashkirian megazone rocks and have been reported by other researchers. Presumably it is the result of the Late Paleozoic syn-collisional remagnetization.</p><p>            According to the new results another component of remanence was detected in the intrusive bodies of the Bashkirian megazone. In 2 sheet bodies and the Main Bakal dyke a component close to the Late Riphean identified earlier in sedimentary rocks of the same region was found (Pavlov, Gallet, 2009; Danukalov et al., 2019). Furthermore, in total 20 thin intrusive bodies and the Main Bakal dyke have paleomagnetic directions close to the Late Paleozoic directions. The comparison of mean paleomagnetic directions for the different studied regions demonstrates the absence of any traces of essential rotation of blocks within the Bashkirian megazone in the Later Paleozoic.</p><p>            At this moment the origin of the remanence of 8 thin bodies is unclear, the nature of the other components of remanence requires additional research. It is planned to sample more intrusive bodies and to perform the isotopic dating of the key objects.</p><p>References:</p><ul><li>1) Pavlov V.E., Gallet Y. Katav limestones: A unique example of remagnetization or an ideal recorder of the Neoproterozoic geomagnetic field. Izvestiya, Physics of the Solid Earth, 2009, vol. 45, no. 1, pp. 31-40</li> <li>2) Danukalov K. N., Salmanova R. Y., Golovanova I. V., Parfiriev N. P. New paleomagnetic data on sedimentary rocks of the Inzer and Zilmerdak formations in the Southern Urals// Materials of the XXV anniversary All-Russian School-Seminar on problems of paleomagnetism and magnetism of rocks. – IPE RAS Moscow, 2019. – P. 108-113</li> </ul>

scholarly journals Reconstruction of the Vendian–Cambrian active continental margin of the Southern Urals: results of studying of detrital zircon from the Ordovician terrigenous rocks

2019 ◽  
pp. 43-59
Author(s):  
A. V. Ryazantsev ◽  
N. B. Kuznetsov ◽  
K. E. Degtyarev ◽  
T. V. Romanyuk ◽  
T. Yu. Tolmacheva ◽  
...  
Keyword(s):  
East European Platform ◽  
Active Continental Margin ◽  
Southern Urals ◽  
Detrital Zircons ◽  
Passive Margin ◽  
Granitic Rocks ◽  
The Southern Urals ◽  
East European ◽  
Volcano Plutonic Belt ◽  
Plutonic Belt

Detrital zircons of Ordovician terrigenous sequences are studied in various Southern Uralian tectonic units.The age of detrital zircons of the West Uralian and Transuralian megazones, Taganai–Beloretsk Zone, and Kraka allochthons spans from the Late Archean to the end of the Vendian– beginning of the Cambrian; Early Precambrian and Early–Middle Riphean zircons are the most abundant. Vendian–Cambrian detrital zircons are strongly dominant in the Uraltau Zone, Sakmara allochthons, and East Uralian Megazone; the zircons of other ages are absent or extremely rare. The Vendian–Cambrian detrital zircons of all Southern Urals zones probably derive from volcanic and granitic rocks of the marginal continental belt, which are part of the Uraltau Zone, Sakmara allochthons, and East Uralian Megazone. The Lu–Hf isotopic characteristics of Vendian–Cambrian detrital zircons indicate that their parental rocks formed on a heterogeneous basement that includes blocks of juvenile and ancient continental crust. According to a model of the pre-Ordovician tectonic evolution of the Southern Urals, at the end of the Late Riphean, the passive margin of the East European Platform collided with a block on a heterogeneous basement. The formation of the block terminated with the Grenville Orogeny. After collision, a volcano-plutonic belt originated in the Vendian–Cambrian at the actively evolved margin of the East European Platform.

The first data on possible Mezozoic magmatism within the Western slope of the Southern Urals

2018 ◽  
pp. 24-34
Author(s):  
A. O. Khotylev ◽  
N. B. Devisheva ◽  
Al. V. Tevelev ◽  
V. M. Moseichuk
Keyword(s):  
Southern Urals ◽  
Western Slope ◽  
Isotopic Age ◽  
The Southern Urals ◽  
Early Proterozoic ◽  
Carbonate Formations ◽  
Two Bodies

Within the Western slope of the Southern Urals, there are plenty of basite dyke complexes of Riphean to Vendian among Precambrian terrigenous-carbonate formations. In metamorphic formations of the Taratash complex (Archean to Early Proterozoic, the northern closure of the Bashkirian meganticlinorium) there was observed the andesitic dyke with isotopic age of 71±1 Ma (U-Pb SHRIMP II on zircons) and near Bakal two bodies of gabbroids with zircons of similar ages were found. These are the first evidence of possible Mezozoic magmatism in this region.

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