scholarly journals Localisation of gold ores in faults of different types

2020 ◽  
pp. 33-43
Author(s):  
E. M. Nekrasov
Keyword(s):  
Fault Zones ◽  
Gold Deposits ◽  
Ore Deposits ◽  
Gold Ores ◽  
Gold Ore ◽  
North East ◽  
Ore Bodies ◽  
Different Types ◽  
Local Shift ◽  
Gold Bearing

The results of the author’s and general works of domestic and foreign geologists, who studied the location of the largest gold deposits in fault zones, characterised by the structure of ore-bearing zones and the concentration of reserves of ores and gold of different scale in them, are presented. The main reasons for such differences are considered. The longest faults on our planet are regional shifts. They are continuously traced for hundreds (up to 1,400) of kilometres along the boundaries of gold-bearing belts and provinces. However, gold ore deposits are located in their zones at extremely limited (point) intervals not exceeding 3—5 km. They are always enclosed between ancient transverse or oblique-oriented fractures of deep, most likely mantle, formation and penetration. In all mineralised faults, gold ore bodies are localised in various geological and structural traps, which are considered in the article and are reflected in the plans and sections. The crossing nodes of regional shifts, as well as overfaults and faults of transverse faults (and dislocations), act as the main promising objects in the deposits search and exploration. Obviously, such nodes should be considered as direct signs of the possible evidence of gold ores. The internal structure of the world leader, gold-bearing Muruntaussky (North-East) local shift (Uzbekistan), studied in detail by the author and other geologists, is given as an example.

scholarly journals Gold Deposits in Chile

2021 ◽  
Vol 48 (1) ◽  
pp. 1
Author(s):  
José Cabello
Keyword(s):  
Porphyry Copper ◽  
Gold Deposits ◽  
Ore Deposits ◽  
Gold Content ◽  
Base Metals ◽  
Porphyry Copper Deposits ◽  
Copper Deposits ◽  
Mineralization Age ◽  
Low Sulfidation ◽  
Gold Bearing

A review of gold and gold bearing base metals deposits in Chile, indicate the existence of at least six different type of ore deposits, most largely formed during the Cenozoic with predominance in the Miocene. Mesozoic deposits are common but less relevant regarding their size and gold content. These hydrothermal ore deposits are genetically associated with subduction related Andean arc magmatism. Due to its relationship with episodic magmatism migrating eastward, there is a tendency for the deposits to be in distinct, north-south trending, belts with a progressive west to east decrease in mineralization age. After analysing 82 cases in total, main gold concentration can be assigned to high-sulfidation epithermal and porphyry type deposits. Low-sulfidation epithermal, IOCG and mesothermal type appears as less relevant. Gold bearing copper deposits constitute an important part of Chile’s total gold production. Both IOCG type but especially porphyry copper deposits are and will remain as a substantial source to supplement the future output of the gold in the country. The 82 deposits with their tonnage and grade studied, represent a total gold content of 11,662 t equivalent to 375 Moz, excluding past production for those exploited. A number of probable gold bearing base metals high tonnage deposits (IOCG and porphyry copper) do not include their gold content in public format, hence the number delivered could be estimated conservative. Methodical geochronological, ore types and zonation studies are required to better appreciate this metallogenic setting widening current understanding and future exploration results.

scholarly journals ON THE AGE AND GEODYNAMIC FACTORS OF THE FORMATION OF GOLD MINERALIZATION AT THE MALINOVKA DEPOSIT

2021 ◽  
Vol 40 (3) ◽  
pp. 28-40
Author(s):  
K.N. Dobroshevsky ◽  
◽  
N.A. Goryachev ◽  
◽  
Keyword(s):  
Gold Mineralization ◽  
Structural Features ◽  
Ore Deposits ◽  
Geodynamic Setting ◽  
Ore Deposit ◽  
Gold Ore ◽  
Shear Structures ◽  
Ore Bodies ◽  
Transform Margin ◽  
Gold Ore Deposit

An interpretation of the first obtained Re-Os dating of pyrite and arsenopyrite of the Malinovsky gold ore deposit is given. A comparison of the obtained data and the known dates of the ore-bearing granitoids of the ore field made it possible to determine the age of mineralization at 100-90 Ma. This age corresponds to the time of completion of the Alb-Cenomanian transform margin of Asia continent geodynamic setting with significant left-shear kinematics, as indicated in the article by the structural features of the localization of ore bodies and magmatic bodies. The distribution of gold ore deposits in this time within the Sikhote-Alin orogenic belt and in the shear structures of the south of the Korean Peninsula are noticeably shown.

The Geochemical Features of Epithermal Gold-Telluride (Au-Te) Ores of the Podgolechnoe Deposit (Central Aldan Ore District, Yakutia)

2017 ◽  
Vol 743 ◽  
pp. 422-425 ◽  
Author(s):  
Yackov Yur’evich Bushuev ◽  
Vasilii Ivanovich Leontev
Keyword(s):  
Sedimentary Cover ◽  
Ore Deposits ◽  
Crystalline Basement ◽  
Alkaline Magmatism ◽  
Epithermal Gold ◽  
Geochemical Composition ◽  
Gold Ores ◽  
Gold Ore ◽  
Gold Telluride ◽  
Ore District

The Central Aldan ore district is a geologically unique area, representing the conjunction zone of the ancient structures of the Archean–Proterozoic crystalline shield, overlain by the Vendian–Cambrian sedimentary cover. The latter was formed in the Mesozoic by intensive alkaline magmatism. Within the Central Aldan ore district, most of primary gold-ore deposits are confined to the sedimentary cover. Until recently it was considered that only ancient complexes in the crystalline basement contain commercial Au-U mineralization. As a result of the geological exploration works over the period of 2003–2006, the Podgolechnoe deposit was discovered. Gold mineralization in this deposit occurs both in rocks of sedimentary cover and crystalline basement. Ore bodies in rocks of the crystalline basement (A-type alkaline deposits) contain epithermal gold-telluride (Au-Te) mineralization, which is new for Central Aldan ore district. This work presents results of the study of geochemical composition of the Podgolechnoe deposit ores and their comparison with typical epithermal gold-ore deposits. In total, 15 samples were studied. The homogeneity of the sample collection, the correlation between Au and other elements, the enrichment coefficients of elements-admixtures, and the REE distribution were analyzed. It was established that gold ores of the Podgolechnoe deposit are geochemically heterogeneous, but, in general, they correspond to the geochemical spectrum characteristic of the gold ores of A-type epithermal deposits. In contrast to Au-U deposits, common in the studied area, ores of the Podgolechnoe deposit show no correlation between gold and uranium.

scholarly journals Gold deposits in the Earth's history

2019 ◽  
Vol 61 (6) ◽  
pp. 3-18
Author(s):  
Nikolay A. Goryachev
Keyword(s):  
Gold Deposits ◽  
Gold Ore ◽  
The Earth ◽  
History Of ◽  
Rodinia Supercontinent ◽  
Archean Crust ◽  
Crustal Origin ◽  
Gold Bearing

The distribution of the main gold deposits in the history of the Earth is considered. Primary heterogeneity of the Archean crust by gold bearing is shown. The main gold ore metallogenic epochs are characterized. Links of gold deposits with VMS and Cu-Ni in the early periods of the Earth (Archaean-Proterozoic) and, in addition, with deposits of W, Mo, Cu, Sb, Hg and Sn in the Phanerozoic are shown. An analysis of the distribution of mineralogical and geochemical types of the actual Au mineralization also showed significant diversity for the Phanerozoic compared with Precambrian. These data reflect the mantle-crustal origin of Au mineralization as a whole and indicates an increase in the contribution of the crust matter to the balance of Au mineralization with the age of the Earth. The well-known interruption in the formation of Au deposits (1.70.8 billion years) was discussed, which was caused by the stable craton regime of the long-existing Columbia (Nuna) Rodinia supercontinent.

Forecast of the stability of the array of gold ore deposits based on the analysis of core material from exploration core drilling wells

2020 ◽  
pp. 216-223
Author(s):  
E. L. Sosnovskaya ◽  
A. N. Avdeev
Keyword(s):  
Underground Mining ◽  
Methodological Approach ◽  
Far East ◽  
Gold Deposits ◽  
Ore Deposits ◽  
Core Material ◽  
Limited Information ◽  
Core Drilling ◽  
Gold Ore ◽  
Gold Ore Deposit

During underground mining of gold deposits it is necessary to promptly assess the degree of stability and potential impact hazard of rocks. A common and reliable source of information on the structure of the deposit is photodocumented core material from exploration core drilling wells. In the course of research of geotechnical processes at gold ore deposits, the authors developed a method of analysis of the degree of core material destruction in order to identify high-tension areas of rock masses. The method is based on a synergetic scientific and methodological approach. The fractal structure of tectonic fractal fracturing obtained as a result of core material analysis is considered as a consequence of a self-organizing process, the nature of which is associated with the dynamics of tectonic movements of the deposit region. The areas of anomalously fractured core detected as a result of the analysis are used as a marker of zones of increased tension and instability of the rock mass. The proposed methodology has been tested in a number of fields in Siberia and the Far East. As an example of the use of the technique, the analysis of the field of destructive elements of the Karalveem field is considered illustratively. The method allows to make an assessment of the geomechanical situation in conditions of limited information about the tectonic structure of the gold ore deposit.

FEATURES OF THE MATERIAL COMPOSITION OF THE VERKHNEYANSKY GOLD-ORE FIELD BREEDS (NORTH BAYKAL)

2018 ◽  
Vol 1 (11(56)) ◽  
pp. 47-52
Author(s):  
V.A. Vanin ◽  
Keyword(s):  
Fault Zone ◽  
Material Composition ◽  
Gold Ore ◽  
Ore Bodies ◽  
Free Gold ◽  
Host Rocks ◽  
Enclosing Rocks ◽  
Gold Bearing

The mineralogical and geochemical features and the material composition of the ore metaso-matites of the Verkhneyanskoye gold ore field (VGOF) have been studied. VGOF is located in the northern part of the Baikal-Muya belt. Ore bodies are represented by linear stockwork of gold-bearing metasomatites that trace the ore-controlling fault zone. Host rocks are ayulindinskiy metavolcanogenic formation, granitoids and gabbros of the yano-mamakan complex. The rocks in the fault zone have been changed to the ore stage. Аs a result, gold bearing (albite) sericite-quartz-chlorite-carbonate metasomatites and gold-bearing quartz-carbonate vein metaso-matites were formed. At the ore stage, the transformation of enclosing rocks into the fault zone with the formation of gold-bearing (albite) sericite-quartz-chlorite-carbonate metasomatites and gold-bearing quartz-carbonate vein. Gold-bearing pyrite-II and pyrite-III-chalcopyrite-II-galena associations were identified on the territory of the VZRP. Free gold and gold in the form of tellurides (petzite, calaverite) in association with altaite and melonite was found in ore bodies

Composition Typomorphic Characteristics of Pyrite in Various Genetic Type Gold Deposits

2012 ◽  
Vol 463-464 ◽  
pp. 25-29 ◽  
Author(s):  
Yu Tong Yan ◽  
Sheng Rong Li ◽  
Bao Jian Jia ◽  
Na Zhang ◽  
Liang Jiang ◽  
...  
Keyword(s):  
Trace Elements ◽  
Gold Deposit ◽  
Major And Trace Elements ◽  
Major Elements ◽  
Gold Deposits ◽  
Genetic Type ◽  
Distribution Characteristics ◽  
Genetic Studies ◽  
Different Types ◽  
Gold Bearing

Pyrite is an ordinary mineral which appears in different types of deposits and it is an important gold-bearing mineral in gold deposits. Through studying the composition typomorphic characteristics of pyrite, we have achieved some genesis information. However, the study on pyrite composition typomorphism in different genesis gold deposits is rare. The paper studied major and trace elements of pyrite of different genetic deposits by using δFe—δS, δFe/δS—As, (Fe+S)—As and Co—Ni—As plot method and achieved major elements characteristics of different deposits. The results show that each genetic type gold deposit has its typical characteristics. This result are well applicable to genetic studies of pyrite in gold deposits and the distribution characteristics are helpful for studying pyrite in gold deposits

scholarly journals Contrasting Surficial Composition of Native Gold from Two Different Types of Gold Ore Deposits

Minerals ◽  
2017 ◽  
Vol 7 (8) ◽  
pp. 142 ◽  
Author(s):  
Vladimir Tauson ◽  
Raisa Kravtsova ◽  
Artem Makshakov ◽  
Sergey Lipko ◽  
Kirill Arsent’ev
Keyword(s):  
Native Gold ◽  
Ore Deposits ◽  
Gold Ore ◽  
Different Types

scholarly journals About the ore conduits at the near-surface deposits of gold-silver ores

2017 ◽  
pp. 37-49
Author(s):  
E. M. Necrasov ◽  
L. A. Dorozhkina
Keyword(s):  
Noble Metals ◽  
Ore Deposits ◽  
Depth Interval ◽  
Near Surface ◽  
Ore Bodies ◽  
Gold Silver ◽  
Exploration Drilling ◽  
Gold Bearing

It is shown that at the rather numerous near-surface gold-silver ore deposits (sometimes with tellurides), developed in the East of Russia, the fractured ore conduits can be revealed. From them, the bundles and a series of vein-veinlet ore bodies or metasomatic gold-bearing rocks start. In both cases the areas with bonanza contents of the noble metals are established. The portion of their stocks sometimes reaches 70% in a total. Exploration drilling along the barren flanks of the ore-conducting channels can identify new ore, hidden in the depth interval from 100-200 to 400 meters or more, and replenish stocks of the deposits.

Ore Mineralization in Adular-Fluorite Metasomatites: Evidence of the Podgolechnoe Alkalic-Type Epithermal Gold Deposit (Central Aldan Ore District, Russia)

2017 ◽  
Vol 743 ◽  
pp. 417-421 ◽  
Author(s):  
Vasilii Ivanovich Leontev ◽  
Yackov Yur’evich Bushuev
Keyword(s):  
Ore Deposits ◽  
Epithermal Gold ◽  
Gold Ore ◽  
Ore Bodies ◽  
Epithermal Gold Deposit ◽  
Ore Minerals ◽  
Ore Mineralization ◽  
Gold Ore Deposit ◽  
Host Rocks ◽  
Ore District

The Podgolechnoe deposit, which belongs to the alkalic-type (A-type) epithermal gold-ore deposits, lies in the Central Aldan ore district (Russia). Gold-ore mineralization is associated with a volcano-plutonic complex made of rocks of the monzonite-syenite formation (J3–K1). The ore bodies are localized in the crushing zones developed after crystalline schists, gneisses, and granites of the crystalline basement complexes (Ar–Pr). Metasomatic alterations in host rocks have potassic specialization. Vein ore minerals are adular, fluorite, roscoelite, sericite, and carbonate. Ore minerals are pyrite, galena, sphalerite, cinnabar, brannerite, monazite, bismuth telluride, stutzite, hessite, petzite, montbraite, and native gold. The deposit has been explored as a gold-ore deposit, however, due to complex composition of ores there is a need to reveal the possibilities of the integrated development of this deposit. This could provide for a reserve increment and an increase in the gross recoverable value of ores due to the extraction of associated components.

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