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LITHOSPHERE (Russia)

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No 6 (2016)
5-32 489
Abstract
The granites are represented significant volumes (up to 50% or more) of the continental upper crust, and, certainly, they should influence on the formation of the crust structure and peculiarities of its evolution. Is generally assumed that after cooling and including in a basement composition, the granites represent the passive volumes and they are not subject to major structural changes. However, some geological data refute this view. In particular, the study of the Northern Tien Shan granites revealed that after cooling and entering the basement they have undergone intense structural reworking. Deformation expresses in cross-scale 3D disintegration of rocks, eventually leading to the emergence of huge masse of kataklasites. That tectonic reworking fundamentally changes the rheology of rocks, causing their 3D kataklastic flow. Going spatial displacement of the granite masses, the formation of domes and vertical and horizontal crystalline protrusions. Postmagmatic tectonics of the granite basement has a significant influence on the formation of tectonic and modern morphological plan of the Tien Shan region.
33-55 449
Abstract
The article analyzes the adequacy of compliance on paleogeodynamic nature of Upper Precambrian sedimentary associations - Bashkir meganticlinorium, Kama-Belaya aulacogene and Uchur-Maya region, received by geological methods and by using discriminant diagrams ?. Meynard et al., B.R. Roser and R. Korsch, and S.P. Verma and ?.S. Armstrong-Altrin. It is shown that among them there are notable differences.
56-69 388
Abstract
The paleokarst occurrences associated with Lower Carboniferous limestones in the east of the Middle Urals are considered. We analyse the nature of the Early-Middle Carboniferous boundary. We argue the absence of a long break at the end of the Early Carboniferous in the Middle Urals. Uplifts were in blocks and quickly destroyed. It's most likely that karst is Meso?oic in age. Probably, two types of its manifest related to different mobility of underground waters that filled karst caverns after their formation.
70-96 396
Abstract
In the paper are given the character of boundary deposits Tournaisian and Visean stage in “Kipchak” section of the Magnitogorsk megazone of eastern slope Southern Urals. It is determined the succession of foraminiferas in the continuous section, specifics of microfaunal associations and their dependence from facies. The description is accompanied by paleontology plates of the foranimifera associations of Kosvian and Obruchevian Horizons. Three new foraminiferas species are described.
97-116 397
Abstract
The main features of the Givetian-Frasnian shoal deposits of the Sub-Polar Urals (Matyashor formation) are considered. The study part of the section corresponds to varcus - rhenana zones on the basis of conodonts. The unconformity corresponding to the upper part of the varcus zone as well as hermanni-cristatus and disparilis zones is detected, the following transgressive sequence is supposed as a sign of the Frasne (Manticoceras) Global Event. Analysis of the sequence allows us to suppose that environment changes in the Matyashor time were controlled by eustatic oscillation of the sea level.
117-128 551
Abstract
For the first time detailed mineralogical research of the Permo-Triassic basalt core samples of Yen-Yakhinskaya superdeep hole SG-7 from the depths of 7673 m, 8009 m and 8250 m was carried. The composition of minerals investigated. It is shown that the transformation of rock occurred in greenschist and prehnite-pumpellyite metamorphic facies at higher temperatures than today's reservoir temperatures. It is shown the proximity of a series of geochemical features to the samples of the Permo-Triassic basalts from other parts of the West Siberian plate, as well as to the trap basalts of rift phase of the Siberian platform. Isotopic ratios Pb were investigated, in one of the samples a significant effect of the tank PREMA and EM1 was revealed.
129-144 440
Abstract
We firstly report compositional and isotope-geochemical characteristics of Ru-Os-Ir(-Pt) alloys, Ru-Os sulfides and polycomponent solid solutions of the system Ru-Os-Ir-Pt (±Fe) derived from the Kimberley Reef within Evander Goldfield of the Witwatersrand Basin (South Africa). The study employed electron microprobe analysis and laser ablation attached to multiple collector inductively coupled plasma mass spectrometry. The obtained results are consistent with: 1) high-temperature formation of the studied platinum-group minerals, 2) sub- hondritic Archean source of platinum-group elements, 3) similarity of the initial Os-isotope composition in coexisting Os-rich alloys and Ru-Os sulfides and 4) significant Os-isotope variations in individual Ru-Os-Ir alloys, Ru-Os sulfides and polycomponent solid solutions of the Ru-Os-Ir-Pt (±Fe) system. 187Os/188Os ages are used to discriminate between different models of noble metal mineralization origin within the Witwatersrand basin.
145-165 1681
Abstract
The Carlin type gold deposits (CTGD) presents large metasomatic bodies of jasperoids in carbonate host rocks, that contain finely dispersed submicroscopic gold in disseminated pyrite or marcasite. The deposits occur in ore clusters that are concentrated along the rather long trends (faults) in the bottom plate of the regional Ro- berts Mountain thrust fault. In recent years, production of gold of this type deposits in the USA alone amounts to 9-10% of the world. The amount of gold produced and in reserves inventory exceeds 10000 tons. Exploration work over the past 10 years have shown that small-area of clusters may have considerable resources at depth. As part of the geological model discussed of the article highlights CTGD classification features, and in the genetic part - to the indicator factors of mineralization. The CTGD formed in a narrow time interval from 42 to 34 Ma, which corresponds to a change in the compression mode to expansion and rejuvenation of magmatism in northern Nevada. No known coeval porphyry copper, skarn or distal Ag-Pb-Zn mineralization in the clusters of CTGD. Similar hydrothermal alteration and ore paragenesis are typical for CTGD: dissolution and silicification of carbonate, sulphidation of Fe in the rock, formation of Au-bearing arsenian pyrite in closed system, and late in open-space deposition of orpiment, realgar and stibnite. Ore signature is Au-Tl-As-Hg-Sb-(Te)-Ва, with low Ag and base metals. There is a high correlation between Au and As, Au, and Tl. The Au/Ag ratio is about 10. Non-boiling ore fluids ranged from ~180 to 240oC and were of low salinity (mostly <6 wt % NaCl eq.) and CO2-be- aring (<4 mol %)/ Illite and local kaolinite indicate acidic fluids. CTGD was formed at a depth of about 3 km.
166-176 542
Abstract
The paleolimnological study of the Lake Tavatui sedimentary record based on a multy-proxy approach provides reconstruction of the Late Glacial and Holocene environments of the Middle Urals. Spore-pollen spectra of the Late Glacial clay reflect several climate shifts between 13.25 and 11.7 ka cal BP. Lithology, mineralogy, geochemistry and spore-pollen spectra of the lake sediment core show follows Holocene environmental changes: ?11.2 ka cal BP, ? 10.6-10.4 ka cal BP, ?9.8 ka cal BP, ? 8.5-7.5 ka cal BP, ?5.8 ka cal BP, ?4.2 ka cal BP, ?3.5 ka cal BP and ? 2.3-2.2 ka cal BP. Lake sediments accumulated since the beginning of human-induced lake level increase (1914-1915 AD) characterized by an increase in Al, K, Rb, Zr, Cs, Be, Sc, V and Ga. These lithophil elements were used as the lake-level fluctuations indicators for the Holocene lake sediments.

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177-184 407
Abstract
Within Sukhoy Ljg-Techa zone of accretion-collision segment of the eastern periphery of the Urals dolerite and gabbro-dolerite dykes and sills are widespread among Upper Devonian-Low Carboniferous terrigenous and carbonate deposits. Geochemical data indicate that dolerites peculiar features of intraplate formations. Features of their structural position and dolerite petrogeochemical characteristics suggest that they formed at the stretch of composite continental crust with important role of large continental terraines.
185-191 381
Abstract
In the Urals Carboniferous 11 algae zones allowing to make interregional and intercontinental correlation of coeval deposits are established by author. For more fractional dividing of carbonate profiles on algoflora for the first time akmezones have been used. In Lower Carboniferous of the Urals are established 9, in Middle and Upper Carboniferous - 5 akmezones.
192-199 350
Abstract
In the second half of the XX century during the Southern Urals regional geological studies GDP-50, GDP-200/2, GDP-1000/3) widely used materials aerial and satellite imagery. Interpretation of these materials revealed widespread in the region lineaments and ring systems morphostructures. Comparison of materials of aerospace survey with different scale geological maps showed that all deposits and most of the occurrences of copper pyrite ore placed on ring morphostructures area that allows us to consider them as additional search features in planning and carrying out of prospecting works. Manifestations of gold confined to the lineament and fault zones.

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ISSN 1681-9004 (Print)
ISSN 2500-302X (Online)