SOME FEATURES OF THE GEOLOGICAL STRUCTURE AND ORE MINERALIZATION OF THE ANOROGENIC GOLD DEPOSITS IN THE WEST OF ALDAN SHIELD (SAKHA-YAKUTIA, RUSSIA)

Abstract Cibaliung is an area that is traversed by the Au-Ag-Cu mineralization pathway from low to intermediate sulfide epithermal system. The implemented techniques for delineating probable gold deposits by the lithology contact and structures that control epithermal gold mineralization systems in the area include first vertical derivative (FHD), vertical derivative (VD), second vertical derivative (SVD), analytic signal (SA), and tilt angle (TA). The results shows that high continuity of anomaly contrast in the direction of Northwest (NW), North-Northwest (NNW), and North-Northeast (NNE) is presumed to be the target geological structure of the study area. Furthermore, the contrast value of magnetic anomaly represents the lithology contact lies in the direction of the West and the East of the area.

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PEMODELAN BAWAH PERMUKAAN MANIFESTASI MINERAL DENGAN METODE GEOMAGNETIK DAERAH PACITAN JAWA TIMUR

KURVATEK ◽

10.33579/krvtk.v4i1.1113 ◽

2019 ◽

Vol 4 (1) ◽

pp. 25-33

Author(s):

Fatimah Fatimah

Keyword(s):

Image Data ◽

Geological Structure ◽

Magnetic Data ◽

Magnetic Intensity ◽

Magmatic Arc ◽

The North ◽

Ore Minerals ◽

Ore Mineralization ◽

Extensional Structure ◽

Anomaly Map

Tulakan Subdistrict, Pacitan Regency, East Java Province. This area is part of the Southern Mountain Zone of East Java, which is the Sunda-Banda magmatic arc of Oligo-Miocene age, where there are alterations and indications of valuable ore minerals. Field magnetic data is taken in an area of 1 x 1 km, with the looping method on the grid trajectory within 200 x 100 m. Then, magnetic data correction and data processing were carried out with Oasis Montaj. From the magnetic anomaly map, the value of high magnetic intensity in the southern part is fresh (intrusive) andesit-dasitic rock as host rock which causes alteration, in the middle has a low magnetic intensity value which is in the direction of the relatively NE-SW river direction, whereas in the north with high intensity is fresh andesite lava. From the image data, it can be seen that the straightness pattern of the geological structure which is dominated by the extensional structure with the direction of NE-SW and E-W is the main trap of epithermal veins carrying ore mineralization mainly Cu, Pb in the study area.

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Accessory and Ore Mineralization of Schists from the Basement of the Yamal Peninsula (Zapadno-Yarotinsky Area, Western Siberia)

UNIVERSITY NEWS. NORTH-CAUCASIAN REGION. NATURAL SCIENCES SERIES ◽

10.18522/1026-2237-2021-2-49-55 ◽

2021 ◽

pp. 49-55

Author(s):

Yuriy V. Erokhin ◽

Kirill S. Ivanov ◽

Anatoliy V. Zakharov ◽

Vera V. Khiller

Keyword(s):

Western Siberia ◽

The Arctic ◽

Yamal Peninsula ◽

Metamorphic Rocks ◽

The West ◽

Temperature Range ◽

Ore Minerals ◽

Ore Mineralization ◽

Native Silver ◽

The Yamal Peninsula

The results of studying the mineralogy of metamorphic schists from the Pre-Jurassic base of the Arctic part of the West Siberian plate are presented. The accessory and ore mineralization of schists from the Zapadno-Yarotinsky license area located in the southern part of the Yamal Peninsula is studied. The schists was uncovered by the Zapadno-Yarotinskaya No. 300 well at a depth of 2762 m. Above the section, the metamorphic rocks are overlain by a young Meso-Cenozoic cover. The schists are mainly composed of quartz, plagioclase (albite), carbonates (dolomite and siderite), mica (muscovite) and chlorite (donbassite). The discovered accessory and ore minerals in the metamorphic schists of the Zapadno-Yarotinsky area can be divided into two groups. The first group includes minerals that were formed during the metamorphism of schists, or were preserved as detrital matter. These minerals include zircon, fluorapatite, and rutile as the most stable compounds. The remaining mineralization (pyrite, sphalerite, chalcopyrite, cubanite, galena, cobaltite, barite, xenotime-(Y), goyazite, synchysite-(Nd), native silver and copper) is clearly secondary and was formed as a result of superimposed metasomatic processes. Judging from the described mineralogy, the schists underwent changes as a result of superimposed propyllitization. The temperature range of this process is determined by the formation of cubanite in association with chalcopyrite at a temperature of 200-210 оС.

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GEOLOGICAL STRUCTURE OF THE SURFACE OF THE PALEOZOIC FOLDED BASE OF THE WEST OF THE TURAN PLATFORM

GEOLOGY GEOGRAPHY AND GLOBAL ENERGY ◽

10.21672/2077-6322-2021-82-3-019-026 ◽

2021 ◽

Vol 82 (3) ◽

pp. 19-26

Author(s):

POPKOV VASILY I. ◽

Keyword(s):

Surface Structure ◽

Oil And Gas ◽

Geological Structure ◽

Comprehensive Analysis ◽

Tectonic Structures ◽

The West ◽

Seismic Surveys ◽

Gravity And Magnetic ◽

Morphostructural Zoning ◽

Gas Potential

The surface of the folded base of the platforms is an important geological boundary separating rock complexes formed in different geodynamic settings and characterized by different physical properties, which largely determine the patterns of formation of minerals in them. Therefore, determining the depth of its occurrence and morphology is not only theoretical, but also practical. Despite many years of studying the foundation of the west of the Turan Platform, there is no unity among geologists and geophysicists in their ideas about its structure, depth of occurrence and surface structure. In this regard, the aim of the work is to build a structural map of the surface of the foundation of the west of the Turan plate, to identify the main tectonic structures and their morphology. The construction is based on a comprehensive analysis of drilling materials and geophysical data. When drawing up the structural map, all the currently available geological and geophysical material was used, including data from drilling, gravity and magnetic surveys, and seismic surveys of various modifications, which made it possible to perform fairly detailed and reliable constructions. The article provides a detailed description of the surface structure of the folded base of the west Turan platform. The obtained results can be used in solving the issues of oil and gas potential of the studied territory. The folded base of the western Turan plate is a heterogeneous and heterochronous formation, differentiated by the depth of occurrence, which allows for morphostructural zoning of its surface.

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III.—Sketch of the Geology of Ice Sound and Bell Sound, Spitzbergen

Geological Magazine ◽

10.1017/s0016756800153907 ◽

1876 ◽

Vol 3 (1) ◽

pp. 16-23 ◽

Cited By ~ 4

Author(s):

A. E. Nordenskiöld

Keyword(s):

West Coast ◽

Geological Structure ◽

High Mountains ◽

The South ◽

Animal Kingdom ◽

The West ◽

Limited Space ◽

Northerly Direction

Ice and Bell Sounds are two large fiords opening out on the west coast of Spitzbergen, which cut deep into the country, both in an easterly direction towards Stor Fiord, and in a northerly direction towards the south part of Wijde Bay. The shores of the Sounds are for the most part occupied by high mountains, precipitous towards the sea, nearly free from snow during the summer, whose sides, being bare of vegetation, offer the observer an uncommonly favourable opportunity for studying the geological structure of the rocks. Within an excecdingly limited space one meets here with a succession of strata belonging to a great many different geological periods, and rich in fossils, both of the vegetable and animal kingdom.

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Sulfur Isotopic Composition of Sulfides of the Au-Te Ore Mineralization in Podgolechnoe and Samolazovskoe Gold-Ore Deposits (Aldan Shield, Russia)

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.769.227 ◽

2018 ◽

Vol 769 ◽

pp. 227-232

Author(s):

Nataliya Rusinova ◽

Vasilii Ivanovich Leontev

Keyword(s):

Isotopic Composition ◽

Significant Contribution ◽

Isotopic Ratio ◽

Aldan Shield ◽

Ore Deposits ◽

Sulfur Isotopic Composition ◽

Magmatic Source ◽

Ore Mineralization ◽

Sulfur Isotopic Ratio ◽

Ore District

This work presents the results of an analysis of the sulfur isotopic composition of pyrites from different metasomatic rocks of the Samolazovskoe and Podgolechnoe (Central Aldan ore district) deposits. The sulfur isotopic ratio of pyrite from ore-bearing metasomatic rocks of the Podgolechnoe deposit is characterized by δ34S values varying in a range from –1.8 to –5.5 ‰; that of pyrite from the Samolazovskoe deposit is in a range from –6.9 to –12.3‰. This is in agreement with the suggestion that a magmatic source made a significant contribution to the formation of the ore-forming fluid.

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XIV.—The Igneous Geology of the Bathgate and Linlithgow Hills

Transactions of the Royal Society of Edinburgh ◽

10.1017/s008045680003444x ◽

1906 ◽

Vol 41 (2) ◽

pp. 359-366

Author(s):

J. D. Falconer

Keyword(s):

Igneous Rock ◽

Sedimentary Rocks ◽

Geological Structure ◽

Physical Geography ◽

Complicated Structure ◽

The West ◽

Geological Surveys

The Bathgate and Linlithgow Hills occupy a well-defined belt of rising ground stretching S.S.W.–N.N.E. from Bathgate to Bo'ness, and included in the marginal portions of sheets 31 and 32 of the 1-in. maps of the Ordnance and Geological Surveys. Throughout the range the steeper slopes face the west, while the eastern flanks are deeply buried in drift. The glaciated contours are well seen from the east, and the sky-line is in several places deeply indented by glacial grooves. The physical geography is throughout intimately dependent upon the geological structure, but the latter is simplicity itself when contrasted with the complicated structure of the shale-fields to the east. Alternating zones of volcanic and sedimentary rocks strike parallel with the direction of elongation of the range from Bathgate to Bonnytoun Hill, and these are cut by a later connected series of dykes and sills of intrusive igneous rock. The latter, as a rule, are more resistant than the lavas, and form the more prominent features of the landscape, while the sedimentary intercalations may frequently be traced, even where no rock is visible, by the trough-like depressions which have been hollowed out of them between the zones of lava.

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A Geological-Geophysical Prospecting Model for Deep-Seated Gold Deposits in the Jiaodong Peninsula, China

Minerals ◽

10.3390/min11121393 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1393

Author(s):

Mingchun Song ◽

Guoqiang Xue ◽

Hongbo Liu ◽

Yixin Li ◽

Chunyan He ◽

...

Keyword(s):

Large Scale ◽

Fault Location ◽

Geophysical Methods ◽

Mining Area ◽

Geological Structure ◽

Gold Deposits ◽

Geophysical Prospecting ◽

Metallogenic Model ◽

Jiaodong Peninsula ◽

Frequency Domain Methods

The North China Craton is one of China’s major gold-producing areas. Breakthroughs have been continually made in deep prospecting at depths of 500–2000 m in the Jiaodong Peninsula, and geophysical methods have played an important role. Given that the geophysical signals of deep-seated gold deposits are difficult to detect, due to their thick overburden layers, conventional geophysical methods are not suitable for deep prospecting. Therefore, this study upgrades the geological-geophysical prospecting model, which is based on the deep metallogenic model and geophysical method of large exploration depths. Based on the analysis of the metallogenic geological factors of the altered-rock-type gold deposits in the fracture zones of the Jiaodong Peninsula, this study proposes that the gold deposits are controlled by large-scale faults, generally occur near the contact interfaces between the Early Precambrian metamorphic rock series and Mesozoic granitoids, and exhibit a stepped metallogenic model. This model then becomes the prerequisite and basic condition for deep prospecting by geophysical methods. For this reason, the traditional geophysical model, which focuses on the exploration of shallow mineralization anomalies, is transformed into a comprehensive multi-parameter geological-geophysical qualitative prospecting model highlighting the exploration of ore-controlling structural planes. The model adopts various frequency domain methods (e.g., CSAMT, AMT, WFEM), reflection seismology, and other methods to detect the deep geological structure. The characteristics of parameters such as gravity and magnetism, resistivity, polarizability, and the seismic reflection spectrum are applied to identify the ore-controlling fault location and dip angle change, and to estimate the ore-bearing location according to the stepped metallogenic model. The prospecting demonstration of deep-seated gold deposits in the Shuiwangzhuang mining area indicates the effectiveness of the comprehensive model. The comprehensive deep prospecting model effectively solves the problem of deep prospecting of gold deposits controlled by faults, promotes the great breakthrough of deep prospecting in the Jiaodong Peninsula, and provides an important technology demonstration for deep prospecting throughout China.

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Productivity Criteria for Complex Reservoirs Based on the Study of Deep-Adsorbed Gases

Oil and Gas technologies ◽

10.32935/1815-2600-2021-133-2-27-30 ◽

2021 ◽

Vol 133 (2) ◽

pp. 27-30

Author(s):

D. A. Kobylinskiy ◽

Keyword(s):

Research Method ◽

Oil And Gas ◽

Geological Structure ◽

Core Material ◽

Test Results ◽

The West ◽

Gas Field ◽

The Core ◽

Oil And Gas Field ◽

Complex Geological Structure

The work is devoted to the development of geochemical criteria for determining the nature of saturation for deep-adsorbed gases in the core. As the object of investigation used the core material selected in the fields in the Nadym-Pyrskoy oil and gas field. In each sample, 72 components were determined, namely, hydrocarbons of different material groups: normal, branched, polycyclic, and aromatic compounds from butane to dodecane. With respect to the quantitative distribution and correlation among the components, qualitative geochemical indicators of sediment productivity have been developed. The saturation character established by the criteria of deep-adsorbed gases was confirmed by the test results. In this regard, this research method significantly increases the effectiveness of diagnostics of prospective deposits, the application of which is relevant in the territory of the West Siberian oil and gas basin, especially when studying deep-submerged deposits of complex geological structure.

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Structural and dynamic conditions for the formation of large orogenic gold deposits in Central and Northeast Asia

LITOSFERA ◽

10.24930/1681-9004-2021-21-3-349-364 ◽

2021 ◽

Vol 21 (3) ◽

pp. 349-364

Author(s):

Yu. S. Savchuk ◽

A. V. Volkov ◽

V. V. Aristov

Keyword(s):

Northeast Asia ◽

Structural Features ◽

Gold Deposits ◽

Ore Deposits ◽

Geological Mapping ◽

Orogenic Gold ◽

Migration Route ◽

Orogenic Gold Deposits ◽

Ore Mineralization ◽

Volumetric Fracturing

Research subject. Large orogenic gold deposits in the fold belts of Central and Northeast Asia.Materials and methods. Geological mapping of various scales on a number of large orogenic gold deposits was conducted using the methods of structural-paragenetic analysis of metamorphic strata, accompanied by obligatory linking of ore mineralization manifestations to specific structures. In a number of cases, various statistical methods were used to geometrize mineralization, identify patterns of its location and determine the paths of paleofluid flows. Available publications on the objects under consideration were reviewed. The geological and structural features of large orogenic gold deposits – Muruntau, Kokpatas, Sukhoi Log and Pavlik – were considered.Results. The Muruntau, Kokpatas and the Sukhoi Log ore deposits are of shariyage-thrust type. Compared to these objects, the Pavlik field is confined to a zone of volumetric fracturing between a series of reverse faults, feathering a large deep fault and belonging to the transpression type. At the Muruntau and Pavlik deposits, the analysis of the location of the most intensive mineralization substantiated the paths of paleofluid flows, along which the fluid migration and ore formation took place.Conclusions. The distribution of ore mineralization in the Muruntau deposit obeys the orientation of planar (cleavage) and linear (orientation of fold hinges) elements. Apparently, the former (main) direction may indicate the orientation and position of the main migration route of ore-bearing fluids, while the latter corresponds to secondary channels, the position of which is due to the intersection of syn-napping structures with favourable lithological horizons. For the Pavlik deposit, the position of ore pillars is compared with the paths of paleofluid flows, the root parts of which are promising for identifying the most powerful and intense mineralization.

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