scholarly journals Relationship between Uranium Minerals and Pyrite and Its Genetic Significance in the Mianhuakeng Deposit, Northern Guangdong Province

Minerals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 73
Author(s):  
Lirong Li ◽  
Zhengqi Wang ◽  
Deru Xu
Keyword(s):  
Uranium Ore ◽  
Ore Bodies ◽  
Calcite Veins ◽  
Mineral Assemblages ◽  
Independent States ◽  
Resource Type ◽  
Uranium Minerals ◽  
Growth Features ◽  
The Relationship ◽  
Northern Guangdong

Granite-related uranium ore is an important uranium resource type in China and worldwide. Whether the uranium geochemical theory “U6+ oxidative migration and U4+ reductive precipitation” is applicable to the granite-related uranium mineralization theory has not been determined. Detailed field and petrographic work, as well as scanning electron microscopy energy spectrum analysis, are conducted in this study to analyze the relationship between uranium minerals and pyrite from different ore types and evaluate the mechanism for the precipitation and enrichment of uranium in the Mianhuakeng uranium deposit of northern Guangdong. Uranium ore bodies in the Mianhuakeng deposit generally occur as vein-filling or vein-disseminated types. Four different kinds of ores are recognized: fluorite, carbonate, siliceous, and reddening types. Despite differences in the mineral assemblages, veined ores share similar characteristics and show that uranium minerals (1) occur in the central part or periphery of vein-filling ores or in interphase arrangements with syn-ore fluorite, quartz, or calcite veins; (2) occur as veinlets or are disseminated in cataclastic altered granite; (3) are inlaid with gangue minerals, primarily calcite, fluorite, and microcrystalline quartz; and (4) are closely associated with pyrite in aggregates or relatively independent states, forming straight boundaries with syn-ore gangue minerals that have euhedral and intact crystals and show mosaic growth features. All these results indicate that both pyrite and uranium minerals are co-crystallized products of the ore-forming fluid. Combined with previous research suggesting that the reducing fluid was sourced from mantle, this study shows that decreased pressure and temperature, as well as changes in pH and the solubility (saturation) of changes, rather than the redox reaction, caused the uranium precipitation in the Mianhuakeng deposit.

Oxidized and reduced mineral assemblages in greenstone belt rocks of the St. Ives gold camp, Western Australia: vectors to high-grade ore bodies in Archaean gold deposits?

2007 ◽  
Vol 43 (3) ◽  
pp. 363-371 ◽  
Author(s):  
Peter Neumayr ◽  
John Walshe ◽  
Steffen Hagemann ◽  
Klaus Petersen ◽  
Anthony Roache ◽  
...  
Keyword(s):  
Western Australia ◽  
Greenstone Belt ◽  
Gold Deposits ◽  
High Grade ◽  
Ore Bodies ◽  
Mineral Assemblages

scholarly journals Spatial distribution of sunflower cultivars and the relationship between growth features

2012 ◽  
Vol 43 (2) ◽  
pp. 338-345 ◽  
Author(s):  
Thomas Newton Martin ◽  
Paulo Sérgio Pavinato ◽  
Leandro Homrich Lorentz ◽  
Renice Paula Zielinski ◽  
Rosana Refatti
Keyword(s):  
Spatial Distribution ◽  
Growth Features ◽  
The Relationship

scholarly journals HERMIONE, EVOLUTION OF ATe-BEARING EPITHERMAL MINERALIZATION, ARGOLIS, HELLAS

2007 ◽  
Vol 40 (2) ◽  
pp. 996 ◽  
Author(s):  
S. Tombros ◽  
K. St. Seymour
Keyword(s):  
Sedimentary Rocks ◽  
Ore Deposits ◽  
Stage I ◽  
Stage Ii ◽  
Quartz Veins ◽  
Minor Contribution ◽  
Epithermal Mineralization ◽  
Ore Bodies ◽  
Calcite Veins ◽  
Sandstone Formation

The Cu-Te-bearing pyrite deposits of Hermione, Argolis are hosted in Miocenic ophiolites. The ophiolites are overlain by a shale-sandstone formation with intercalations of limestones and manganiferous sedimentary rocks. The ore deposits form irregular lenticular or stratiform ore bodies, and veins. These ore bodies are related to volcanic activity in an arc-related rift at the margins of a palaeocontinent. Late N- to NNE-trending, sinistral, milky quartz-pyrite-calcite veins cut the host ophiolites. Alteration haloes of quartz-calcite, albite-sericitechlorite, and chalcedony-epidote-clay minerals are developed in the lavas as concentric shells, or as envelops that parallel the quartz veins. The telluriumbearing mineralization is developed in two successive stages, characterized by the assemblages: pyrite-(pyrrhotite)-magnetite-chalcopyrite-sphalerite (Stage I) and galena-sphalerite-freibergite-marcasite-chalcocite (Stage II), followed by a supergene stage. The cobaltiferous pyrite-chalcopyrite geothermometer defined two ranges of last-equilibration temperatures: 220° to 250°Cfor Stage I, and 120° to 195°Cfor Stage II. The calculated δ18 Ο and SD compositions of the mineralizing fluids, at 200° and 250°C, reflect the dominance of a magmatic component. The calculated δ SH2S fluid values reveal a magmatic source for the sulphur, with minor contribution from submarine sediments, whereas tellurium is proposed to be derived from a mafic-ultramafic source.

Financial Scams Through Ponzi Schemes

2021 ◽  
pp. 271-292
Author(s):  
Alam I. Asadov
Keyword(s):  
Financial Literacy ◽  
Financial Sector ◽  
Policy Recommendations ◽  
Commonwealth Of Independent States ◽  
Financial Regulations ◽  
Financial Sector Development ◽  
Fertile Ground ◽  
Independent States ◽  
Cis Countries ◽  
The Relationship

This chapter investigates the relationship between financial literacy, financial sector development, and Ponzi schemes in the commonwealth of independent states (CIS) countries. It begins with an overview of the early cases of Ponzi schemes in the CIS countries by examining circumstances which formed fertile ground for the schemes to develop during initial years of independence. The study then scrutinised the situation in the member states during the later years which revealed no improvements. A closer examination of the problem discovered that the main triggers are low level of financial literacy and scarce investment alternatives. The chapter suggests that unless the level of financial literacy is raised and the financial sector is developed, Ponzi schemes will continue to thrive in the region. It concludes by providing some policy recommendations to enhance financial literacy and financial sector development, as well as necessary steps to improve financial regulations.

Eurasian Integration and Problems of Civil Society

2020 ◽  
pp. 117-134
Author(s):  
Elena Stetsko
Keyword(s):  
Civil Society ◽  
Political Thought ◽  
Political Integration ◽  
Eurasian Economic Union ◽  
Independent States ◽  
Soviet Space ◽  
Economic Union ◽  
The Relationship ◽  
Post Soviet Space ◽  
Discussion Topic

The сhapter studies the relationship between the development of integration processes and the development of civil society in the post-Soviet space and, in particular, in the countries of the Eurasian Economic Union. It consists of five parts. The introduction presents the main trends and vectors of integration processes in the post-Soviet space. The first part considers the concept of “civil society” and its features in Western and Russian political thought. The second part highlights the features of building a civil society in the independent states of the EAEU. General points and differences in the emerging civil societies of the EAEU countries are revealed. Further, in the fourth part, the “Eurasian idea” is considered in terms of its compatibility with the peculiarities of the development of civil society in the post-Soviet space. The final part proposes a discussion topic on the possibility of political integration within the EAEU.

The genesis of Proterozoic uranium deposits in Australia

1979 ◽  
Vol 291 (1381) ◽  
pp. 339-353 ◽  
Keyword(s):  
Precious Metals ◽  
Mineral Deposits ◽  
Uranium Deposits ◽  
The West ◽  
Acid Magma ◽  
Uranium Ore ◽  
Connate Water ◽  
Ore Bodies ◽  
Mineralizing Fluids ◽  
Proterozoic Age

The principal mineral deposits of Proterozoic age in Australia, not only of uranium but also of base and precious metals, are found within a north-trending belt central to the continent which stretches from Adelaide to Darwin. This belt represents the margin to the West Australian Archaean craton, and comprises orogenic and shelf domains that evolved throughout the Proterozoic; and it is suggested that the formation of the uranium deposits was an integral part of the evolution of the various geosynclines in the belt. The uranium ore bodies occupy structurally prepared features such as shears, faults and breccias, and are clearly introduced, but the source of the mineralizing fluids, and the precise mechanism of deposition, is, in some cases at least, in dispute. Mineralization per ascensum by connate water carrying metals desorbed from the sedimentary pile, or in association with acid magma which may itself be the product of anatexis, is favoured by the author.

scholarly journals ANALYSIS OF THE RELATIONSHIP BETWEEN ENERGY CONSUMPTION AND ECONOMIC GROWTH IN THE COMMONWEALTH OF INDEPENDENT STATES

2020 ◽  
Vol 10 (4) ◽  
pp. 318-324
Author(s):  
Aziza Syzdykova ◽  
Gulmira Azretbergenova ◽  
Khairulla Massadikov ◽  
Aigul Kalymbetova ◽  
Darkhan Sultanov
Keyword(s):  
Economic Growth ◽  
Energy Consumption ◽  
Commonwealth Of Independent States ◽  
Independent States ◽  
The Relationship

Gold–copper–bismuth mineralization in hedenbergitic skarn, Tombstone Mountains, Yukon

1987 ◽  
Vol 24 (12) ◽  
pp. 2362-2372 ◽  
Author(s):  
Isobel J. Brown ◽  
Bruce E. Nesbitt
Keyword(s):  
Large Scale ◽  
Small Volume ◽  
Gold Mineralization ◽  
Rock Interaction ◽  
The North ◽  
Mineral Assemblages ◽  
Intrusive Rocks ◽  
Porosity And Permeability ◽  
Relationship Of ◽  
The Relationship

Gold mineralization on the Marn property, Yukon, occurs in two pyroxene skarn bodies, which are adjacent to the Mount Brenner Stock in the Ogilvie Mountains. The skarns are separated by a 600 m wide monzonite intrusion and show contrasting mineralogical and geochemical characteristics in addition to quite different metal values. Significant but uneconomic Au, Ag, W, and Cu mineralization is found in skarn on the north side of the intrusion, while very low Au grades (0.052 g/t) occur at the southern contact. The mineral assemblages of both skarns are dominated by iron-rich pyroxenes. The iron content of the pyroxenes varies between Hd40 and Hd80 in the northern location and Hd80 and Hd100 in the southern skarn. A well-developed sequence of retrograde alteration affected only the northern skarn. This was probably the result of porosity and permeability differences in the early, high-temperature pyroxene skarn, which permitted greater fluid–rock interaction in the northern skarn during cooling. A small volume of diopsidic, aluminous, wollastonite-bearing skarn occurs in both the northern and southern localities. The relationship of this type of skarn to the hedenbergitic skarn is ambiguous, since there is no large-scale mineralogical zoning. The Marn is similar to hedenbergitic, auriferous skarns of Japan, where the oxidation state of the intrusive rocks is believed to be the controlling factor in the development of skarn mineralogy.

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