scholarly journals Source and Tectonic Setting of Porphyry Mo Deposits in Shulan, Jilin Province, China

Minerals ◽  
2019 ◽  
Vol 9 (11) ◽  
pp. 657 ◽  
Author(s):  
Nan Ju ◽  
Sen Zhang ◽  
Lin-Lin Kou ◽  
Hai-Po Wang ◽  
Di Zhang ◽  
...  
Keyword(s):  
Tectonic Setting ◽  
Ore Deposits ◽  
Jilin Province ◽  
Ore Bodies ◽  
Low Concentrations ◽  
Ore Minerals ◽  
High Concentrations ◽  
Polymetallic Ore ◽  
Porphyry Mo Deposits ◽  
Early Yanshanian

The Shulan area in Jilin Province is a part of the Lesser Xing’an–Zhangguangcai Range polymetallic ore belt, which is an important Cu–Mo ore region of northeast China. The discovery of three large Mo ore deposits (Fu’anbu, Chang’anbu, and Jidetun) highlights its potential for porphyry Mo ore deposits. Here we investigated the tectonic setting and mineralization of Mo ore deposits in the Shulan area, based on comparative study of the Fu’anbu, Chang’anbu, and Jidetun deposits. The ore-controlling structures are NE–SW- and NW–SE-trending faults. The main ore mineral in all three deposits is molybdenite. The ore bodies are all hosted in granites, have a stratiform or lenticular shape, and have strongly altered wall rocks. These observations indicate the Mo deposits in the Shulan area are typical porphyry Mo deposits. All were formed during the early Yanshanian (199.6–133.9 Ma). Biotite adamellites from the Chang’anbu deposit yield a U–Pb age of 182.10 ± 1.20 Ma. Molybdenites from the Fu’anbu and Jidetun deposits have Re–Os isochron ages of 166.9 ± 6.7 and 169.1 ± 1.8 Ma, respectively. Quartz and ore minerals were analysed for H–O and S–Pb isotopes, respectively. The results suggest the ore-forming materials were predominantly of upper-mantle origin, with secondary contributions from the lower crust. The ore-hosting granites have high concentrations of SiO2 (66.67–75.43 wt.%) and Al2O3 (12.91–16.44 wt.%), low concentrations of MgO (0.09–1.54 wt.%), and Ritman index (σ = K2O + Na2O)2/(SiO2 − 43)) ratios of 2.09–2.57. The granites are enriched in large-ion lithophile elements and depleted in high-field-strength elements, and have negative Eu anomalies. The ore-hosting rocks are geochemically similar to granites in northeastern China that were generated in a collisional orogeny. We conclude that early Yanshanian (199.6–133.9 Ma) mantle–crust-derived magmatism caused by the subduction of the Palaeo-Pacific Plate was the main source of Mo deposits in the Shulan area.

On genesis of massive sulfide polymetallic ore deposits of Rudny Altai

2021 ◽  
pp. 3-16
Author(s):  
B. DIYACHKOV ◽  
M. MIZERNAYA ◽  
A. PYATKOVA ◽  
A. BISATOVA ◽  
A. MIROSHNIKOVA ◽  
...  
Keyword(s):  
Precious Metals ◽  
Massive Sulfide ◽  
Ore Deposits ◽  
Vertical Range ◽  
Long Duration ◽  
Ore Minerals ◽  
Ore Mineralization ◽  
High Concentrations ◽  
Individual Grains ◽  
Polymetallic Ore

Many geologists assign most of large- and medium-sized massive sulfide polymetallic ore deposits of Eastern Kazakhstan to the VMS type. These ore deposits formed in the Devonian, under conditions of rifting and active basalt-andesite-rhyolite volcanism. Ore bodies of these deposits are noted to be clearly confined to formations of several geochronologic levels (D1e to D3fm). Hydrothermal-sedimentary syngenetic and hydrothermal-metasomatic ores are distinguished. High concentrations of base metals in the ores (above 10 % sum metals) and their rather simple mineral composition (chalcopyrite, pyrite, galena, and sphalerite) are a characteristic feature of all the massive sulfide polymetallic ore deposits of Rudny Altai. The ores are noted to be multicomponental, with elevated contents of the admixtures of precious metals and rare elements (Cd, Se, Bi, Te, Ta, W, etc.). Mineralogical investigations of the ores have demonstrated an intricate relationships of the major ore minerals (chalcopyrite, pyrite, sphalerite, galena) that exhibit several generations and different geochemical specialization. Minerals of Au, Ag, Te, Bi, and other elements are encountered as individual grains or microscopic inclusions and stringers in minerals of Cu, Pb, and Zn. A significant vertical range of the ore mineralization (more than 100 m), the complexity and long duration of the ore-forming processes, the clearly defined confinement of the ore mineralization to certain geochronologic levels, – all these allow us to suppose a possibility of discovery of new ore lodes or individual ore deposits within the already known ore fields of the Kazakhstan segment of Rudny Altai

Compositional peculiarities of the host rocks and ores of the Lazursky ore field, Zmeinogorsk ore region of the Rudny Altai minerogenic zone

2021 ◽  
pp. 36-47
Author(s):  
Tatyana SERAVINA ◽  
Svetlana KUZNETSOVA ◽  
Ludmila FILATOVA
Keyword(s):  
Massive Sulfide ◽  
Ore Deposits ◽  
Sulfide Ores ◽  
Volcanogenic Massive Sulfide ◽  
Sulfide Deposits ◽  
Ore Bodies ◽  
Ore Minerals ◽  
Copper Pyrite ◽  
Host Rocks ◽  
Volcanogenic Massive Sulfide Deposits

The article describes composition of the host rocks and ores of the Lazursky and Maslyansky polymetallic volcanogenic massive sulfide deposits of the Lazursky ore field located within the Zmeinogorsk ore region of the Rudny Altai minerogenic zone. The ore field is composed of various facies of the Devonian (Late Givetian – Frasnian) ore-bearing siliceous-terrigenous basalt-rhyolite formation containing horizons of synvolcanic metasomatites. All rocks of the ore field were subjected to folding and schistosity with zones of tectonic brecciation. Hydrothermal alterations are represented by carbonatization and chloritization. The ore bodies exposed at the Lazursky and Maslyansky ore deposits are represented by copper-pyrite, copper, and zinc-copper-pyrite massive sulfide ores and other varieties. The major ore minerals of the deposits are chalcopyrite, pyrite, sphalerite, marcasite, and pyrrhotite.

scholarly journals The Status of Arsenic Pollution in the Greek and Cyprus Environment: An Overview

Water ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 224 ◽  
Author(s):  
Spyros K. Golfinopoulos ◽  
Soterios P. Varnavas ◽  
Dimitrios E. Alexakis
Keyword(s):  
Human Health ◽  
Regional Climate ◽  
Ore Deposits ◽  
Arsenic Pollution ◽  
Water Stream ◽  
As Species ◽  
Low Concentrations ◽  
The Status ◽  
High Concentrations ◽  
Very High

This study presents an overview about the arsenic (As) contamination and its sources in two European countries. Arsenic is a highly toxic element in its inorganic form and it is carcinogenic to human seven in low concentrations. The occurrence of As in surface water, stream and marine waters, groundwater, bottled water, sediment, soil, mines, and seafood, its environmental origin, and its impacts on human health are discussed. The classes of Geoaccumulation Index for As in Greece ranges from practically uncontaminated to extremely contaminated, and in Cyprus varies between practically uncontaminated and heavily contaminated. In many cases, the As contamination reaches very high concentrations and the impacts may be crucial for the human health and ecosystems. Physicochemical properties, regional climate and geological setting are controlling the occurrence and transport of As. In Greece and Cyprus, the geology, lithology, and ore-deposits are the most important factors for the variation of As contents in water, soil, and sediment. The dominant As species are also determined by the location and the redox conditions. The findings of this paper may be useful for scientists and stakeholders monitoring the studied areas and applying measures for protection of the human and terrestrial ecological receptors (plants, avian, mammals).

scholarly journals Fluid Inclusions and C-H-O-S-Pb Isotope Systematics of the Changfagou Deposit, Jilin Province, Northeast China

Geofluids ◽  
2018 ◽  
Vol 2018 ◽  
pp. 1-21 ◽  
Author(s):  
Bo Peng ◽  
Bile Li ◽  
Jun Chen
Keyword(s):  
Partial Melting ◽  
North China Craton ◽  
Lower Crust ◽  
North China ◽  
Tectonic Setting ◽  
Ore Deposits ◽  
Jilin Province ◽  
Magmatic Fluid ◽  
Northern Margin ◽  
The North

The Changfagou Cu deposit in Jilin province, China, is located in the eastern segment of the northern margin of the North China Craton and lies at the southern end of the Lesser Xing’an Mountains-Zhanggangcailing Mountains. According to the mineral paragenetic association and its various relationships, the hydrothermal mineralization can be divided into 4 metallogenic stages from early to late: stage I is K-feldspar-quartz-magnetite, stage II is quartz-molybdenite, stage III is quartz-chalcopyrite (polymetallic sulfide), and stage IV is carbonate. Stages II and III are the main metallogenic stages. Overall, the metallogenic fluid associated with the Changfagou deposit is characterized as a F-rich CO2-H2O-NaCl hydrothermal system. The hydrogen and oxygen isotopic characteristics suggest the initial ore-forming fluids of the Changfagou deposit evolved from a primitive magmatic fluid and mixed with meteoric water. The sulfur and lead isotopic characteristics show that the metallogenic material was derived from partial melting of the lower crust. Phase separation or immiscibility is the important mechanism in the precipitation of molybdenum, whereas a decrease in temperature is the important mechanism in the precipitation of copper polymetallic sulfides. The above characteristics are similar to those of the porphyry deposits related to continental environments. Compared with the deposits in the Xilamulun metallogenic belt, both have similar metallogenic ages and tectonic positions. In conclusion, the Changfagou deposit formed in an intracontinental extensional environment due to lithospheric thinning. The mineralization was related to magmatism associated with partial melting of the lower crust. The intersection of the Dunhua-Mishan fracture and Kangbao-Chifeng fracture along the northern margin of the North China Craton is a promising location for porphyry ore deposits related to a continental tectonic setting.

Geoelectrochemical-Extraction Measurement Method to Look for Hidden Lead-Zinc Ore Deposit and Prospecting Effect

2013 ◽  
Vol 734-737 ◽  
pp. 95-99 ◽  
Author(s):  
Yun Hu Hu ◽  
Xi Jun Liu ◽  
Xiang Rong Luo
Keyword(s):  
Electric Field ◽  
Metal Ions ◽  
Measurement Method ◽  
Ore Deposits ◽  
Ore Deposit ◽  
Ore Bodies ◽  
Lead Zinc ◽  
Ore Prospecting ◽  
Polymetallic Ore

The geoelectrochemical-extraction measurement is a ore prospecting method of deep-penetrating geochemistry, by using the element receptors to extract the mobile metal ions from the soil under the artificial electric field to look for the hidden ore deposit. The study of using the geoelectrochemical-extraction measurement method to look for blind lead-zinc ore deposit has been carried out in the Fuzichong lead-zinc polymetallic ore deposit and Panlong lead-zinc ore deposit of Guangxi, which resulted in the clearly geoelectrochemical anormaly above the known ore bodies. And the ore prospecting forecast conducted in the unknown ore regions shows that it is feasible to use the geoelectrochemical-extraction measurement method to expore the deep hidden lead-zinc ore 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.

Formation of native arsenic in hydrothermal base metal deposits and related supergene U6+ enrichment: The Michael vein near Lahr, SW Germany

2020 ◽  
Vol 105 (5) ◽  
pp. 727-744
Author(s):  
Manuel Scharrer ◽  
Katharina Sandritter ◽  
Benjamin F. Walter ◽  
Udo Neumann ◽  
Gregor Markl
Keyword(s):  
Solid Solution ◽  
Transition Metals ◽  
Base Metal ◽  
Hydrothermal Fluids ◽  
Thermodynamic Calculations ◽  
Ambient Conditions ◽  
Weathering Processes ◽  
Low Concentrations ◽  
Ore Minerals ◽  
High Concentrations

Abstract Native arsenic is an occasional ore mineral in some hydrothermal base metal deposits. Its rarity (compared to pyrite, arsenopyrite, galena, sphalerite, or chalcopyrite, for example) is surprising, as arsenic is a common constituent of upper crustal fluids. Hence, the conditions of formation must be quite special to precipitate native arsenic. An ideal location to investigate the formation of native As and to explore the parameters constraining its crystallization is the Michael vein near Lahr, Schwarzwald, southwest (SW) Germany. Here, galena, sphalerite, and native arsenic are the most abundant ore minerals. The two important ore stages comprise (1) galena-barite and (2) sphalerite-native arsenic-quartz, the latter with a general mineral succession of pyrite → sphalerite ± jordanite-gratonite solid solution → galena → native As. The native arsenic-bearing mineralization formed by cooling of an at least 130 °C hot saline fluid accompanied by a reduction due to the admixing of a sulfide-bearing fluid. Thermodynamic calculations reveal that for the formation of native arsenic, reduced conditions in combination with very low concentrations of the transition metals Fe, Co, and Ni, as well as low sulfide concentrations, are essential. “Typical” hydrothermal fluids do not fulfill these criteria, as they typically can contain significant amounts of Fe and sulfide. This results in the formation of arsenides, sulfarsenides, or As-bearing sulfides instead of native arsenic. Very minor amounts of pyrite, sulfarsenides, and arsenides record the very low concentrations of Fe, Co, and Ni present in the ore-forming fluid. High concentrations of aqueous Zn and Pb lead to early saturation of sphalerite and galena that promoted native arsenic precipitation by decreasing the availability of sulfide and hence suppressing realgar formation. Interestingly, native arsenic in the Michael vein acted as a trap for uranium during supergene weathering processes. Infiltrating oxidizing, U+VI-bearing fluids from the host lithologies reacted under ambient conditions with galena and native arsenic, forming a variety of U+VI (±Pb)-bearing arsenates such as hügelite, hallimondite, zeunerite, heinrichite, or novacekite together with U-free minerals like mimetite or anglesite. Some parts of the vein were enriched to U concentrations of up to 1 wt% by this supergene process. Reduced (hypogene) uranium phases like uraninite were never observed.

The Pb-Zn Deposits and Mineralization during Cambrian in Chongqing Area of Yangtze Platform, China

2012 ◽  
Vol 455-456 ◽  
pp. 1390-1393
Author(s):  
Min Quan Xia ◽  
Gui Wen Xu ◽  
Xue Juan Da ◽  
Lan Chen
Keyword(s):  
Mineral Composition ◽  
Tectonic Setting ◽  
Wall Rock ◽  
Ore Deposits ◽  
Yangtze Platform ◽  
Ore Minerals ◽  
Host Rocks ◽  
Middle Strata

This paper presented the Pb-Zn deposits characteristics in southeast Chongqing. The Pb-Zn deposits occurred in Lower-Middle strata with develop the dolomites, limestones as ore-bearing host-rocks. They are veined, stratifed, stratoid, and lenticular in shape and locally pinch and swell with dominant ore minerals of sphalerite, galena, and pyrite . the Pb-Zn ore deposits grade changed from 0.32% to 7.06% for Pb and 4.21% to 14.29% for Zn. The Gaodongzi orebody has highest concentrations of Pb with 7.06% record and Zn with 14.29% record. The tectonic setting, ore-host rocks, wall-rock alternation, and mineral composition will control the Pb-Zn deposits distribution in Chongqing area.

Neutrophil Elastase Potentiates Cathepsin G-lnduced Platelet Activation

1992 ◽  
Vol 68 (05) ◽  
pp. 570-576 ◽  
Author(s):  
Mary A Selak
Keyword(s):  
Neutrophil Elastase ◽  
Cell Activation ◽  
Thromboxane A2 ◽  
Creatine Phosphate ◽  
Dense Granule ◽  
Cathepsin G ◽  
Dependent Manner ◽  
Concentration Dependent Manner ◽  
Low Concentrations ◽  
High Concentrations

SummaryWe have previously demonstrated that human neutrophil cathepsin G is a strong platelet agonist that binds to a specific receptor. This work describes the effect of neutrophil elastase on cathepsin G-induced platelet responses. While platelets were not activated by high concentrations of neutrophil elastase by itself, elastase enhanced aggregation, secretion and calcium mobilization induced by low concentrations of cathepsin G. Platelet aggregation and secretion were potentiated in a concentration-dependent manner by neutrophil elastase with maximal responses observable at 200 nM. Enhancement was observed when elastase was preincubated with platelets for time intervals of 10–60 s prior to addition of a low concentration of cathepsin G and required catalytically-active elastase since phenylmethanesulphonyl fluoride-inhibited enzyme failed to potentiate cell activation. Neutrophil elastase potentiation of platelet responses induced by low concentrations of cathepsin G was markedly inhibited by creatine phosphate/creatine phosphokinase and/or indomethacin, indicating that the synergism between elastase and cathepsin G required the participation of ADP and thromboxane A2. On the other hand, platelet responses were not attenuated by the PAF antagonist BN 52021, signifying that PAF-acether did not play a role in elastase potentiation. At higher concentrations porcine pancreatic elastase exhibits similar effects to neutrophil elastase, demonstrating that the effect of elastase was not unique to the neutrophil protease. While neutrophil elastase failed to alter the ability of cathepsin G to hydrolyze a synthetic chromogenic substrate, preincubation of platelets with elastase increased the apparent affinity of cathepsin G binding to platelets. In contrast to their effect on cathepsin G-induced platelet responses, neither neutrophil nor pancreatic elasatse potentiated aggregation or dense granule release initiated by ADP, PAF-acether, arachidonic acid or U46619, a thromboxane A2 mimetic. Moreover, unlike its effect on cathepsin G, neutrophil elastase inhibited thrombin-induced responses. The current observations demonstrate that elastase can potentiate platelet responses mediated by low concentrations of cathepsin G, suggesting that both enzymes may function synergistically to activate platelets under conditions where neutrophil degranulation occurs.

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