scholarly journals Conditions of localization and patterns of distribution of gold-poly-metal mineralization of the Dagkesaman deposits (Lesser Caucasus, Azerbaijan)

2021 ◽  
Vol 30 (3) ◽  
pp. 528-538
Author(s):  
Mamoy I. Mansurov ◽  
Ulker I. Kerimli ◽  
Azer I. Guseynov
Keyword(s):  
Structural Factors ◽  
Structural Elements ◽  
Mineral Association ◽  
Zonal Structure ◽  
Gold Ore ◽  
Physical Chemical ◽  
Ore Bodies ◽  
Polymetallic Mineralization ◽  
Lesser Caucasus ◽  
Chemical Conditions

We studied the structural-morphological types and mineral composition of ore bodies, stages of ore development and conditions of development of the deposits. The research revealed significant elements of the corresponding conditions of localization of gold-polymetallic mineralization, the most characteristic being albitophyre subvolcanic bodies and steeply-dipping damages related to them. According to the structural-morphologic peculiarities, the ore bodies should be united under three categories: 1) simple vein; 2) complex vein; 3) veinlet-impregnation types. The positions of gold ore bodies and their morphological peculiarities were found to be determined by structural factors. Presence of small ruptures, differently-oriented systems of fractures and faults, which run across the area, gentle curves of these systems and other structural elements –all of this promotes gold ore development. There research determined aureoles of ore-containing altered rocks (serialization, chloritization, kaolization and calcinations, and limonitization from hypergenical zones) and presence of zonal structure. Gold-productive areas were identified as the quartz-pyrite association with disperse gold, and especially, the second mineral association where there is a notable close paragenetic connection between noticeable gold and chalcopyrite-galena parageneis of polymetallic stage. In the process of ore development, the physical-chemical conditions have presumably changed from average deep (quartz-pyrite-sericite) to shallow (quartz-galena- sphalerite-gold ore) and close-to-the-surface (quartz-chalcocite-hematite). Gold that occurs with all the mentioned minerals of this stage has developed in the temperature interval of 220–160 °C. The study found the ores to be complex, containing the following dditional elements: Fe, Cu, S, Bi, Zn, Pb, As, Se, Te. The main fossil component is gold. Industrially valuable are also cadmium, zink, copper and silver, found in the ores. We found the following morphological types of grains of native gold: homogenous, zonal, mono-granular, spotted, which are of great significance for concluding on genesis of the deposits, prognoses, explorations and assessments.

scholarly journals Tungsten Ores of the Dzhida W-Mo Ore Field (Southwestern Transbaikalia, Russia): Mineral Composition and Physical-Chemical Conditions of Formation

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 725
Author(s):  
Ludmila B. Damdinova ◽  
Bulat B. Damdinov
Keyword(s):  
Mineral Composition ◽  
Fluid Inclusions ◽  
Apical Part ◽  
Hydrothermal Fluids ◽  
True Temperature ◽  
Gangue Mineral ◽  
Mineral Formation ◽  
Physical Chemical ◽  
Homogenization Temperatures ◽  
Chemical Conditions

This article discusses the peculiarities of mineral composition and a fluid inclusions (FIs further in the text) study of the Kholtoson W and Inkur W deposits located within the Dzhida W-Mo ore field (Southwestern Transbaikalia, Russia). The Mo mineralization spatially coincides with the apical part of the Pervomaisky stock (Pervomaisky deposit), and the W mineralization forms numerous quartz veins in the western part of the ore field (Kholtoson vein deposit) and the stockwork in the central part (Inkur stockwork deposit). The ore mineral composition is similar at both deposits. Quartz is the main gangue mineral; there are also present muscovite, K-feldspar, and carbonates. The main ore mineral of both deposits is hubnerite. In addition to hubnerite, at both deposits, more than 20 mineral species were identified; they include sulfides (pyrite, chalcopyrite, galena, sphalerite, bornite, etc.), sulfosalts (tetrahedrite, aikinite, stannite, etc.), oxides (scheelite, cassiterite), and tellurides (hessite). The results of mineralogical and fluid inclusions studies allowed us to conclude that the Inkur W and the Kholtoson W deposits were formed by the same hydrothermal fluids, related to the same ore-forming system. For both deposits, the fluid inclusion homogenization temperatures varied within the range ~195–344 °C. The presence of cogenetic liquid- and vapor-dominated inclusions in the quartz from the ores of the Kholtoson deposit allowed us to estimate the true temperature range of mineral formation as 413–350 °C. Ore deposition occurred under similar physical-chemical conditions, differing only in pressures of mineral formation. The main factors of hubnerite deposition from hydrothermal fluids were decreases in temperature.

Geochemical Features of the Tulallar Gold Ore Field

2021 ◽  
pp. 39-51
Author(s):  
Vasif Mamad Aga oglu Baba-zadeh ◽  
Narmina Nazim kyzy Ismayilova ◽  
Nazim Ajdar oglu Imamverdiyev ◽  
Shakhla Faig kyzy Abdullaeva
Keyword(s):  
Positive Relationship ◽  
Weak Correlation ◽  
Mineral Association ◽  
Mineral Associations ◽  
Western Block ◽  
Mine Workings ◽  
Lesser Caucasus ◽  
Bismuth Tellurides ◽  
Impurity Elements ◽  
Dispersed Gold

The article discusses the geochemical features of the Tulallar gold field in the Lesser Caucasus. Distributions of gold and accompanying elements (Ag, As, Hg, Bi, Cu, Zn) in metasomatically altered rocks taken from mine workings (ditches, adits, etc.) and wells are considered. The results of analyzes of furrow samples showed that the content of Au ranges from 0.4 ppm to 37.5 ppm, Ag - from 0.5 ppm to 48.4 ppm. In strongly kaolinized, weakly limonitized quartzites, the Au content ranged from 0.4 to 1.2 ppm, Ag - from 4.0 to 8.8 ppm. In the well drilled in the Central Block, closer to the surface, the siliceous breccias contain Au 309-363 ppm, Ag 132-250 ppm, and high As, Bi and Hg contents are also noted. A similar picture is observed in the silicified rocks of the wells of the Western block. Correlations between Au, Ag and other impurity elements were determined using the STAT program. A direct positive correlation has been established between Au and Ag, Au and Bi, Au and Hg. A positive relationship was also found between Ag and Bi, Ag and Hg. Cluster analysis revealed two different mineral associations: 1) native elements and their compounds - minerals and 2) polysulfide. The closest connection is observed between Ag, Hg and Au. Mineralogically, the Ag-Hg-Au-Bi cluster apparently corresponds to an early ore association - electrum, bismuth tellurides, possibly with inclusions of finely dispersed gold. The second, polymetallic cluster is characterized by a weak correlation bond Аs-Сu-Zn, which indicates that polysulfides were deposited later. The largest amount of Au was deposited in the early mineral association.

scholarly journals Ecological Factors Preventing Restoration of Degraded Short Tussock Landscapes in New Zealand’s Dryland Zone

2017 ◽  
Vol 2 (1) ◽  
Author(s):  
Anna P. Rodrigues ◽  
Elena Moltchanova ◽  
David A. Norton ◽  
Matthew Turnbull
Keyword(s):  
Water Availability ◽  
Ecological Factors ◽  
Woody Species ◽  
Biotic Factors ◽  
Introduced Herbivores ◽  
Physical Chemical ◽  
Native Woody Species ◽  
Dryland Ecosystems ◽  
Survival And Growth ◽  
Chemical Conditions

AbstractBiotic factors such as the presence of invasive animal and/or plant species are well known as major causes of ecological degradation and as limiting either natural or assisted (human-induced) ecological restoration. However, abiotic aspects of the landscape, such as water availability and soil physical/chemical conditions can also potentially limit restoration and should be considered. Dryland ecosystems are amongst the world’s most threatened and least protected. New Zealand’s drylands have been drastically changed, initially through burning, agricultural and grazing practices and the impacts of introduced herbivores and plants. This research aimed at identifying some of the key environmental factors preventing the reestablishment of native woody species in a New Zealand dryland ecosystem. The experiments involved a combination of shading, irrigation and grazing exclusion. The results showed that supplemental water was not beneficial for the survival and growth of the native seedlings, unless combined with shade. Fencing proved important for establishment, even though the species used are regarded in the literature as unpalatable to herbivores. The results indicated that the presence of shade was fundamental for the establishment and growth of the native seedlings likely due to improvements in the microclimate, soil aeration, and water availability to seedlings.

scholarly journals STRUKTUR KOMUNITAS ZOOPLANKTON DI PERAIRAN KABUPATEN LOMBOK UTARA, PROVINSI NUSA TENGGARA BARAT

2018 ◽  
Vol 18 (2) ◽  
Author(s):  
Muhammad Junaidi ◽  
Nurliah Nurliah ◽  
Fariq Azhar
Keyword(s):  
Water Quality ◽  
Community Structure ◽  
Aquatic Ecosystems ◽  
Zooplankton Community ◽  
Geographical Information ◽  
Zooplankton Community Structure ◽  
Ecological Index ◽  
Physical Chemical ◽  
Chemical Conditions

ABSTRAKMengingat peranan zooplankton dalam ekosistem perairan sangat penting, maka dilakukan penelitian dengan tujuan untuk menganalisis struktur komunitas zooplankton yang meliputi jenis, kelimpahan, dan indek ekologi, dan  kaitan  distribusi zooplankton dan kualitas perairan di Perairan Kabupaten Lombok Utara. Pengumpulan data dirancang dengan sistem informasi geografis (SIG) pada 23 stasiun pengamatan yang ditentukan dengan teknik acak sederhana.  Hasil penelitian menunjukkan bahwa jenis dan kelimpahan zooplankton yang ditemukan di Perairan Kabupaten Lombok Utara cukup bervariasi dengan jumlah genus  sebanyak 9 yang terbagi  dari  5 kelas.  Berdasarkan perhitungan indeks ekologi menunjukkan bahwa struktur  komunitas zooplankton dalam kategori perairan yang kurang stabil. Kelimpahan dan indeks ekologi zooplankton  dipengaruhi oleh kondisi lingkungan (fisik-kimia) perairan antara lain  kecerahan, pH dan oksigen terlarut. Kata kunci : zooplankton,  struktur komunitas, kualitas perairan, kelimpahanABSTRACTConsidering that the role of zooplankton in aquatic ecosystems is very  important, research is carried out with the aim of analyzing zooplankton community structure which includes the type, abundance, and ecological index, and the relation of zooplankton distribution and water quality in North Lombok Regency Waters. Data collection was designed with a geographical information system (GIS) on 23 observation stations that were determined by simple random techniques. he results of this study indicate that the type and abundance of zooplankton found in the waters of North Lombok Regency are quite varied with the number of genus as many as 9 which are divided into 5 classes. Based on the calculation of the ecological index shows that the zooplankton community structure is in the category of less stable waters. The abundance and ecological index of zooplankton is influenced by the environmental (physical-chemical) conditions of the waters including brightness, pH and dissolved oxygen. Keywords: zooplankton, community structure, water quality, abundance 

scholarly journals CARACTERISTICAS FISICO-QUIMICAS DE LA BAHIA DE SANTA MARTA (AGOSTO 1980 - JULIO 1981)

2016 ◽  
Vol 13 ◽  
Author(s):  
Gustavo Ramírez T.
Keyword(s):  
Surface Water ◽  
Water Column ◽  
Annual Cycle ◽  
Water Column Stability ◽  
Physical Chemical ◽  
Chemical Conditions

Physical-chemical conditions have been studied in the Bay of Santa Marta, Colombian Caribbean, from August 1980 to July 1981. The results obtained at nine stations indicate that the surface water is rather homogeneous and of mainly oceanic character. In the period from december to april water temperatures were lowest (<25®C), salinity highest (>36°/oo) and undersaturation with oxigen occured (<91%) these factors together with pH, alcalinity and the variation of water column stability are indicating an upwelling phenomenon in this period and allow the stablishment of an approximated model for the annual cycle the bay.

Temperature effects on bank filtration: redox conditions and physical-chemical parameters of pore water at Lake Tegel, Berlin, Germany

2010 ◽  
Vol 1 (1) ◽  
pp. 55-66 ◽  
Author(s):  
A. Gross-Wittke ◽  
G. Gunkel ◽  
A. Hoffmann
Keyword(s):  
Water Temperature ◽  
High Water ◽  
Nitrate Respiration ◽  
Redox Processes ◽  
Redox Potentials ◽  
Bank Filtration ◽  
Physical Chemical ◽  
Drinking Water Production ◽  
Chemical Conditions ◽  
Sediment Layers

In the city of Berlin, artificial groundwater recharge techniques, such as bank filtration and infiltration ponds, are an important source for drinking water production. Climate change with increasing surface water temperatures can influence the water purification processes during bank filtration mainly due the intensification of metabolic processes leading to a decrease of oxygen and an increase of anaerobic conditions. In Lake Tegel a significant increase of water temperature in the epilimnion of 2.4°C within the last 30 years was recorded. For a better understanding of induced bank filtration at Lake Tegel, redox processes and physical-chemical conditions within the surface sediment layers (0–26 cm depth) at the littoral infiltration zone were investigated. The influence of temperature in the range of 0–25°C on microbial catalysis of redox processes, such as reduction of nitrate and sulphate, was examined during the period March 2004–June 2005. High water temperatures (16–25°C) were accompanied by negative redox potentials (EH=−47 mV) and decreasing Ninorg concentrations, while the amount of ammonia, Mn2 +  and Fe2 +  was rising. This indicates redox processes such as denitrification, Mn4 +  reduction, nitrate respiration and ammonification, as well as Fe3 +  reduction. The reduction of sulphate, however, has not yet become significant at Lake Tegel, but with increasing water temperature, sulphate reduction must be expected.

scholarly journals FTIR analysis of chemical changes in wood induced by steaming and longitudinal compression

Cellulose ◽  
2020 ◽  
Vol 27 (12) ◽  
pp. 6811-6829 ◽  
Author(s):  
Mátyás Báder ◽  
Róbert Németh ◽  
Jakub Sandak ◽  
Anna Sandak
Keyword(s):  
Functional Groups ◽  
Cell Walls ◽  
Beech Wood ◽  
Industrial Applications ◽  
Structural Elements ◽  
Longitudinal Compression ◽  
Chemical Mechanisms ◽  
Modification Process ◽  
Physical Chemical ◽  
Detailed Interpretation

Abstract Pleating is an optimal way to increase bendability of wood used in diverse industrial applications. It results in the excessive buckling of cell walls and modifications of constitutive polymers. However, thoughtful understanding of the physical–chemical mechanisms of that modification process is very limited. The main purpose of the present study was to identify changes in functional groups of wood polymers induced by longitudinal compression. Four types of wood samples prepared from beech and sessile oak (untreated, steamed, longitudinally compressed and fixated for 1 min as well as longitudinally compressed and fixated for 18 h) were assessed by infrared spectroscopy. The spectra interpretation revealed that changes can be observed in hydroxyl as well as in carbon–oxygen single and carbon-hydrogen functional groups of polysaccharides and lignin. Beech wood seems to be more susceptible to investigated modification processes as compared to oak. Detailed interpretation of infrared spectra allows identification of changes in the hygroscopicity of wood as well as alterations in the linkage between structural elements in the polymer matrix of wood induced by the applied treatments. Graphic Abstract

Heterotrophic nitrifying/aerobic denitrifying bacteria: Ammonium removal under different physical-chemical conditions and molecular characterization

2019 ◽  
Vol 248 ◽  
pp. 109294 ◽  
Author(s):  
Lívia Carneiro Fidélis Silva ◽  
Helena Santiago Lima ◽  
Tiago Antônio de Oliveira Mendes ◽  
Adilson Sartoratto ◽  
Maira de Paula Sousa ◽  
...  
Keyword(s):  
Molecular Characterization ◽  
Denitrifying Bacteria ◽  
Ammonium Removal ◽  
Physical Chemical ◽  
Chemical Conditions

Palaeogeographic controls on palygorskite occurrence in Maastrichtian-Palaeogene sediments of the Western High Atlas and Meseta Basins (Morocco)

Clay Minerals ◽  
2014 ◽  
Vol 49 (4) ◽  
pp. 595-608 ◽  
Author(s):  
A. Knidiri ◽  
L. Daoudi ◽  
M. El Ouahabi ◽  
B. Rhouta ◽  
F. Rocha ◽  
...  
Keyword(s):  
Depositional Environment ◽  
Chemical Precipitation ◽  
X Ray Diffraction ◽  
High Atlas ◽  
X Ray ◽  
Smectite Clays ◽  
Physical Chemical ◽  
Mineralogical Characteristics ◽  
The Difference ◽  
Chemical Conditions

AbstractThe Maastrichtian-Palaeogene series of the Western High Atlas and Meseta Basins in Morocco are particularly rich in palygorskite. The present work is aimed at clarifying the genesis of palygorskite from the interbedded facies and gaining an understanding of their relationships with the depositional environment. The mineralogical characteristics of palygorskite from these series were studied by X-ray diffraction (XRD) and electron microscopy (SEM/TEM). The palygorskite content and microstructure show large geographical and stratigraphical variations in the deposits studied. The palygorskite occurrence is directly related to palaeobathymetry, since it is the dominant clay mineral in shallow marine and restricted environments. According to the morphology of palygorskite crystallites, four types of textures were distinguished. These types of palygorskite are polygenetic, formed by chemical precipitation, by the recrystallization of smectite clays or reworked by wind or water from sub-aerial environments. The difference between the two studied sub-basins with respect to palygorskite occurrence is attributed to the palaeomorphology of the hinterlands, to the tectonic differentiation and to the physical-chemical conditions of seawater.

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