scholarly journals Provenance reconstructions. Article 3. Modern research methods for heavy detrital minerals (garnet, tourmaline, chromespinelide, rutile, chloritoid, pyroxene and amphibole)

LITOSFERA ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 149-167 ◽  
Author(s):  
L. V. Badida ◽  
A. V. Maslov ◽  
G. A. Mizens
Keyword(s):  
Lower Triassic ◽  
Southern Urals ◽  
Upper Permian ◽  
Research Subject ◽  
The Southern Urals ◽  
Important Data ◽  
Accessory Minerals ◽  
Clastic Rocks ◽  
Parent Rocks ◽  
Composition Of Minerals

Research subject. This article considers accessory minerals, which, unlike zircons, are present in the vast majority of common clastic rocks. Materials and methods. The data on the chemical composition of minerals (garnet, tourmaline, chromespinelide, rutile, chloritoid and clinopyroxene) extracted from the Riphean and Vendian, as well as Upper Permian and Lower Triassic sandstones of the Southern Urals, were used to illustrate the features of applying various methods and techniques. In addition, numerous examples from publications are presented. Results. A number of modern methods for studying accessory minerals, which might be used to elucidate the composition and characteristics of the provenance rocks for terrigenous strata, were reviewed. Conclusions. It is shown that, similar to zircons, accessory minerals possess a significant potential in terms of providing important data on parent rocks.

scholarly journals The sources of zircons in clastic rocks of the Riphean deposits of the Urals

2019 ◽  
Vol 488 (4) ◽  
pp. 413-419
Author(s):  
A. A. Krasnobaev ◽  
V. N. Puchkov ◽  
N. D. Sergeeva ◽  
S. V. Busharina
Keyword(s):  
Southern Urals ◽  
Detrital Zircons ◽  
The Other ◽  
The Urals ◽  
The Southern Urals ◽  
Clastic Rocks ◽  
Lower Riphean ◽  
Age Variations ◽  
Age Determinations

New age determinations of detrital zircons of sandstones augmented the possibilities of interpretation of their provenance. This interpretation is often restricted by a formal comparison of age-and-composition characteristics of detrital crystals with any very distant model objects. A different situation arises when the role of a source of a detritus is claimed by local objects. The analysis of SHRIMP and TIMS - datеs of zircons and U and Th concentrations in them, and also a comparison of histograms of primary zircons from Riphean volcanics and rocks of the Taratash complex on one hand and the detrital zircons from the sandstones of Vendian (Asha series) and Lower Riphean (Ai Formation) on the other, have shown that the age variations of sources and clastics are comparable in many aspects. It means that the age characteristics of primary zircons from the Riphean volcanics and rocks of the Taratash complex as sources of zircon clastics for the Riphean and Vendian sandstones in the Southern Urals are regulated by processes of resedimentation, though the influence of distant sources is not excluded.

scholarly journals Garnet-amphibole miaskites of the Ilmenogorsky miaskite massif (Southern Urals): Mineralogy and geochemistry

LITOSFERA ◽  
2020 ◽  
Vol 20 (5) ◽  
pp. 652-667
Author(s):  
A. B. Nemov
Keyword(s):  
Mineral Composition ◽  
Microprobe Analysis ◽  
Southern Urals ◽  
Crustal Material ◽  
Research Subject ◽  
Accessory Minerals ◽  
Low Concentrations ◽  
Garnet Composition ◽  
Icp Ms ◽  
High Concentrations

Research subject. This paper presents original findings about textural-structural, mineralogical, petrological, and geochemical features of the garnet-amphibole miaskites (firstes) of the Ilmenogorsky miaskite massif.Materials and methods. The microprobe analysis of mineral composition was performed using Tescan Vega3 sbu and REMMA202M scanning microscopes equipped with microanalyzers. The content of major, trace and rareearth elements (REE) in rock samples was determined by the methods of AAS and ICP-MS.Results. The garnet-amphibole miaskites under study are characterized by a rare mineral paragenesis, i.e. garnet-amphibole-pyroxene-nepheline-plagioclase. The mafic minerals exhibit a high ferruginosity (f = 70–99), while the accessory minerals have high Al, F and low REE contents. The garnetamphibole miaskites contains high concentrations of Al, Fe3+, Ca, Na, Be, Rb, Mo, Tl and low concentrations of LILE, HFSE, REE and transit elements.Conclusions. According to the garnet composition and its ferruginosity (f = 95– 99), high contents of Al and F in accessory minerals, the prevalence of Fe3+, as well as negative Eu/Eu* and positive Ce/ Ce* anomalies, the garnet-amphibole miaskites under study are assumed to be the product of acid-alkaline metasomatism occurring under the oxidizing conditions of petrogenesis. The low ratios of Cr/V and Ni/Co indicate the immobility of transit elements during metasomatism, and their clarke of concentration corresponds to the content in metaterrigenous and metacarbonate rocks, which suggests crustal substratum for garnet–amphibole miaskites. Garnet-amphibole miaskites are the markers of the interaction of crustal material with deep fluids, which occurred during the stage of shear tectonics development (270–240 Ma) due to the broad permeability of the rocks composing the Ilmenogorsky miaskite massif.

scholarly journals Enstatite nodules in the harzburgites of the Southern Urals

LITOSFERA ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 386-408
Author(s):  
V. G. Korinevsky
Keyword(s):  
Southern Urals ◽  
Research Subject ◽  
The Southern Urals ◽  
Fine Grained ◽  
Composition And Structure ◽  
Northern Shore

Research subject. At two points on the northern shore of Lake Uvil’dy in the Southern Urals, two outcrops of unique rocks – nodular harzburgites – were discovered in the tectonic lenses of serpentinite melange among garnet-biotite gneisses of the Ilmenogorsko-Vishnevogorsky Сomplex. These outcrops form a body of about 9 m in thickness among amphibolized orthopyroxenites.Results. The fine-grained serpentinized enstatite-olivine matrix of the harzburgites under study contains numerous spherical formations (nodules) 2–7 cm in diameter, composed of large enstatite crystals and rare forsterite grains. The composition and structure of these spheroids are highly similar to the enstatite chondrules from stony meteorites, although differing in size (ten times larger).Conclusions. Such structures are very rare in hyperbasites and occur in slightly altered varieties. Judging by the microstructural features and relationships of the main minerals, it is concluded that these minerals were crystallized from a magmatic melt.

Riphean fine-grained aluminosilicate clastic rocks in the Southern Urals, Uchur-Maya area, and the Yenisei Kryazh: Principal litho-geochemical characteristics

2008 ◽  
Vol 46 (11) ◽  
pp. 1117-1144 ◽  
Author(s):  
A. V. Maslov ◽  
A. D. Nozhkin ◽  
V. N. Podkovyrov ◽  
E. F. Letnikova ◽  
O. M. Turkina ◽  
...  
Keyword(s):  
Southern Urals ◽  
Geochemical Characteristics ◽  
The Southern Urals ◽  
Fine Grained ◽  
Clastic Rocks ◽  
Maya Area

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.

ABOUT THE PHYTOCENOTIC ROLE OF THE DARKNOUS SPECIES IN THE SOUTHERN URALS

2017 ◽  
Vol 212 (12) ◽  
pp. 48-50
Author(s):  
Ju.P. Gorichev ◽  
◽  
A.N. Davydychev ◽  
A.Yu. Kulagin ◽  
◽  
...  
Keyword(s):  
Southern Urals ◽  
The Southern Urals
Sign in / Sign up

Export Citation Format

Share Document