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金牌女王《GOLD》
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作者 张琳(整理) 张戎(整理) 《大观周刊》 2010年第32期17-17,共1页
暑期档大行其道,纯爱剧、校园剧和刑侦剧都开始粉墨登场.主演天海佑希向来善演硬朗的角色,主演剧集的名字少不了“女王”二字。
关键词 “金牌女王” 《gold》 电视剧 天海佑
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Characteristics of Gold Mineralization at the Baguiomo Gold Panning Site, Koudougou Region, Burkina Faso, West Africa
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作者 Pascal Ouiya Aziz Fayçal Tarnagda Martial Eric Fozing 《Open Journal of Geology》 CAS 2024年第1期1-18,共18页
The Birimian Baguiomo formations are located in the northern part of the Boromo greenstone belt. In this belt, the volcanic rocks (tholeiitic basalt, calcalkaline basalt, andesite) hosting the gold mineralization are ... The Birimian Baguiomo formations are located in the northern part of the Boromo greenstone belt. In this belt, the volcanic rocks (tholeiitic basalt, calcalkaline basalt, andesite) hosting the gold mineralization are located in the Kwademen-Baguiomo shear zone. This mineralization, located only a few kilometers from the Kwademen gold deposit, is uncharacterized and, together with the latter, could constitute a gold potential capable of being economically exploitable. It is in this sense that this work is carried out with a view to characterizing the gold mineralization of the Baguiomo gold panning site. To carry out this work, we have made direct field measurements, combined with microstructures, and combined all this with data from geochemical rock analysis of the basalts that are the main host formations. Geochemical data show that tholeitic basalts formed from a mantle plume that was emplaced in an oceanic plateau context. Calc-alkaline basalts and andesites are comparable to Paleoproterozoic tholeitic basalts (PTH3), which are slightly enriched in light rare earths. Fertility tests show that these basalts concentrate between 3 and 6 ppb of gold at the time of accretion, which is sufficient for remobilization of this primary gold during the Eburnian orogeny to yield a deposit of around 4 - 5 Moz. Gold mineralization is associated with pyrite crystals when the latter are disseminated in the rock mass, whereas it is associated with hematite in quartz veins concordant with S1 shear deformation. It is mainly the pyrite crystals in the pressure shadows that contain the gold grains, whose development would be synchronous with micro-shear zone reactivation during the first phase of D1<sub>B</sub> deformation. The second phase of D2<sub>B</sub> deformation, which is a crenulation or fracture schistosity, does not significantly affect the shear deformation that controls mineralization. 展开更多
关键词 Kwademen-Baguiomo Shear Zone gold Panning Site gold Mineralization Eburnian Orogeny
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Assessing the Impact of Gold Mining on the Quality of Water Resources in the Commune of Meguet, Burkina Faso
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作者 Issoufou Ouedraogo Samuel Lankoande +3 位作者 Yacouba Konate Boukary Sawadogo Nicolas Kagambega Martin Lompo 《Journal of Water Resource and Protection》 CAS 2024年第4期281-292,共12页
Despite its often illegal nature, artisanal gold mining in Burkina Faso contributes to the economic and social development of the country. However, the rudimentary techniques used in gold panning have a significant im... Despite its often illegal nature, artisanal gold mining in Burkina Faso contributes to the economic and social development of the country. However, the rudimentary techniques used in gold panning have a significant impact on the environment due to inappropriate practices and the use of various chemical substances. This study aims to assess the impact of artisanal gold mining on the quality of water resources in a rural community at Méguet, Burkina Faso. To this end, surface and groundwater samples were collected and analyzed at the BUMIGEB laboratory. Field results show that the waters are slightly alkaline (6.97 < pH < 8.1), weakly mineralized and conductive (124 < EC < 543 μS/cm), with temperatures ranging from 24.6˚C to 31.6˚C. In addition, trace metals (TMEs) analyzed from surface and subsurface waters show very high levels, generally deviating from the levels recommended by WHO guidelines for Burkina Faso. Trace metals contamination of water resources in the commune of Méguet is mainly due to Fe (3.78 - 11.12 mg/kg), Hg (0.03 - 0.29 mg/kg), As (0.01- 6.31 mg/kg) and Pb (0.01 - 3.8 mg/kg). This study can serve as a basis for guiding national environmental policies to protect the water resources of the Méguet mine. 展开更多
关键词 gold Panning Water Quality Trace Metal Méguet Burkina Faso
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Multi-Scale Approach for Gold Targeting in Côte d’Ivoire Paleoproterozoic Rocks
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作者 Martial Pohn Koffi Adingra Yao Augustin Koffi +3 位作者 N’guessan Nestor Houssou Zié Ouattara Tokpa Kakeu Lionel-Dimitri Boya Marc Ephrem Allialy 《Open Journal of Geology》 CAS 2024年第2期155-176,共22页
The aim of this study is to contribute to better targeting of gold prospecting areas using geospatial information. To this end, 3 mining sites were selected for the study. They are: the Sénoufo belt (Barrick Gold... The aim of this study is to contribute to better targeting of gold prospecting areas using geospatial information. To this end, 3 mining sites were selected for the study. They are: the Sénoufo belt (Barrick Gold mine), the Yaouré complex (Perseus Mining mine) and the South Fetêkro belt (Bonikro, Hiré and Agbaou mines). For this study, a multi-scale approach was carried out at regional, mine and microscopic levels. At the regional scale, a comparative analysis of 1:200,000 scale geological maps revealed that 3 main lithologies are regularly repeated on and around the various mining sites. These are: undifferentiated volcanics, metagranodiorites and metasiltites dominated by meta-arenites. Most of these lithologies are affected by undifferentiated faults generally oriented NE-SW, N-S, ENE-WSW and WNW-ESE. In addition, gold and manganese occurrences are present on all the sites studied. At the mine scale, radarsat-1 images processing indicate that the main mining sites are generally located near or at the intersection of lineaments-oriented NE-SW or N-S on the one hand and E-W or ENE-WSW or WNW-ESE or again NW-SE on the other. These mines are also located at the interface between zones of high and low lineament density. At the microscopic scale, petrographic studies of undifferentiated volcanic samples from the various sites indicate that they consist of andesites, meta-andesites and tuffs. 展开更多
关键词 gold Targeting Undifferentiated Volcanics Mineral Occurrences LINEAMENTS Côte d’Ivoire
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Lithostructural Control of the Gold Mineralization of the Douta Permit of African Star Resources (Kédougou-Kéniéba Inlier, Southeastern Senegal)
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作者 Masse Ndour Papa Moussa Ndiaye +3 位作者 Koffi Félix Ekra Alain Ndong Malick Faye Pierre Ndour 《International Journal of Geosciences》 CAS 2024年第4期303-333,共31页
The Douta permit of African Star Resources/Thor Explorations, located in the southeast of Senegal, in the Kédougou-Kéniéba Inlier (western part of the West African Craton), is dominated to the East by m... The Douta permit of African Star Resources/Thor Explorations, located in the southeast of Senegal, in the Kédougou-Kéniéba Inlier (western part of the West African Craton), is dominated to the East by metasedimentary formations such as greywackes, shales, graphitic shales, quartzites, cherts, claystones and breccias characteristic of the Dialé-Daléma basin. To the West, the mafic formations of the Mako volcanic belt are the most common. Metasedimentary rocks are associated with metavolcanosedimentary terms found at the contact zones between the two (2) Birimian groups. These different geological formations are cut by mafic dolerite and gabbro sills and/or dykes, as well as quartz and microgranite veins. The Douta gold project is crossed from North to South by the MTZ (Main Transcurrent Zone), generally oriented NE-SW and becoming N-S towards the North. The permit is characterized by several shear corridors. The rocks are affected by brittle, brittle-ductile to ductile deformations. The gold mineralization is hosted by a NE-trending shear corridor called the Makosa corridor (Makosa shear zone), therefore sub-parallel to the MTZ. It has a subvertical dip (75˚ to 85˚ to the NW). It is associated with a hydrothermal phase characterized by quartz-sericite-epidote-fine, disseminated pyrite and arsenopyrite ± albite ± chlorite paragenesis. These minerals testify to the existence of a low degree of metamorphism (greenschist facies, epizonal domain) in the area. However, metamorphism reaches amphibolite facies in some places, particularly in the vicinity of intrusive bodies, with the presence of hornblende (amphiboles) and plagioclase. The gold mineralization is mainly hosted by two (2) metasedimentary lithological units: meta-greywackes and shales. 展开更多
关键词 Douta Kédougou-Kéniéba Inlier Senegal Metasedimentary MTZ Control gold Mineralization Makosa Corridor
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Gold Mineralisation in the Intiédougou Prospect (Diébougou District) in Southwest Burkina Faso, West African Craton
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作者 Yao Honoré Koffi Wendkouni Passecdé Pauline Zongo +1 位作者 Nanema Mathieu Urbain Wenmenga 《Journal of Minerals and Materials Characterization and Engineering》 2024年第1期63-77,共15页
The Intiédougou located in the Houndé Birimian greenstone belt has been the subject of several mining and geoscience studies that have led to the discovery of mineralized gold targets. One of these mineraliz... The Intiédougou located in the Houndé Birimian greenstone belt has been the subject of several mining and geoscience studies that have led to the discovery of mineralized gold targets. One of these mineralized targets has prompted work that raises the issue of control factors for the gold mineralization of the prospect. The methodology used in this study combines a study of core drill hole data located in the area and laboratory studies. The Intiédougou sector is based on andesito-basaltic, andesitic interstratified volcanoclastite rocks and Tarkwaïen type detrital sedimentary rocks caught in a vice in the volcano-sedimentary unit. Lithostructural analysis of the sector shows that the subvolcanic rocks bearing gold mineralization are subjected to heterogeneous ductile to brittle deformations and affected by hydrothermalism evolving at stages marked by large fissure fillings. These hydrothermal phases evolve in the zones of expansion created by the brittle deformations that have contributed to the deposits of different types of gold-enriched sulphides. These different phases of hydrothermal destabilization generally of low degree accompany the tardi to post-eburnean brittle tectonics. This deformation system is favorable to the establishment of gold mineralization in the form of vein bodies. The overimposition of deformed and altered areas suggests a genetic relationship between deformation and hydrothermal activity. In conclusion, the mineralization of Intiédougou in vein styles, set up in a volcanic arc environment with a paragenesis of gold-pyrite deposit ± chalcopyrite would be controlled by the structural aspect and accompanied by hydrothermal alteration. 展开更多
关键词 Intiédougou Prospect SHEAR HYDROTHERMAL Tarkwaïan gold Mineralization
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Applicability of Gravity Separation Method on the Ashashire Gold Ore Deposit from Benishangul Gumuz Region, Western Ethiopia
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作者 Misganu Kabeta Mulugeta Sisay Cheru Goitom Gebreyohannes Berhe 《International Journal of Nonferrous Metallurgy》 2024年第2期21-31,共11页
The study was conducted to determine the applicability of gravity separation method on the Ashashire gold ore deposit Benishangul gumuz region, western Ethiopia. The Ashashire composite was produced to provide suffici... The study was conducted to determine the applicability of gravity separation method on the Ashashire gold ore deposit Benishangul gumuz region, western Ethiopia. The Ashashire composite was produced to provide sufficient mass for this study and experiment, including sample preparation, mineralogical analysis of gold and associated elements, gravity concentration, and data interpretation and analysis. During the study, a grind optimization was conducted on the composites sample with varying grind size to evaluate the effect of grind size on gold recovery. The ore was moderately ground to the standard grind size of 80%, passing 106 µm, 75 µm, 53 µm and this nominal size was selected for the preliminary assessment for concentration optimization for this deposit. The gravity testing comprised three-stage concentration using Knelson concentrator. High recovery of gold from the gravity concentrates was achieved from the second gravity concentration. Based on the laboratory experimental result analysis, a grind size of P80 75 µm is selected as optimal size for the Ashashire gold deposit. Increasing the grind size from P80 of 75 µm to 106 µm decreases the recovery rate from 75% to 54%, or decreasing the grind size from P80 of 75 µm to 53 µm decreases the gold recovery rate to 37%. The native gold grain in the ores is mostly associated with quartz and fine gold is closely associated with pyrite. According to analysis of the fire assay, chemical, and mineralogical data, only gold and telluride is commercially valuable elements in the ores. Predominantly gold was occurred in the native form of Au-Te. The sample subjected to gravity separation assayed about 2.6 g/t Au. 展开更多
关键词 ORE GANGUE Ashashire Gravity Method gold TELLURIDE Concentration Knelson
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Experimental Abrasion Study of the Evolution of Gold Morphological Criteria in Different Sediments as a Function of Time
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作者 Fary Diome 《Open Journal of Soil Science》 2024年第1期13-27,共15页
The use of gold as a tracer element for understanding the mode of emplacement of these formations requires a good knowledge of its dynamics. To this end, we have carried out experimental studies to investigate the evo... The use of gold as a tracer element for understanding the mode of emplacement of these formations requires a good knowledge of its dynamics. To this end, we have carried out experimental studies to investigate the evolution of contour states (regular, irregular), surface states (blunt, rough), shape (elongation) and dimension (size). The study of these criteria is carried out on SEM photos of particles, taken before and after the experiment, using Aphelion image processing software. Five experiments were carried out to study the influence of sediment granulometry and water dilution on particle morphological changes. The results of these experiments show that coarse sediments (>1 mm) are largely responsible for morphological changes in gold. They cause fragmentation and/or folding of the particle edges, depending on the magnitude of the impact forces. Strong impacts due to high water dilution cause staking on the particle surface. Fine sediments (<1 mm) slow down particle evolution as they cushion impacts and particles tend to flatten rather than fragment. 展开更多
关键词 Weathering Mantles Experimental Abrasion gold
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Characteristics of Gold and Its Mineralization Style in the Boulon Djounga Eastern Perimeter of Liptako Mining Company (Central Southwestern Niger)
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作者 Gambo Ranaou Noura Kamayé Tourba +2 位作者 Karimou Dia Hantchi Bouba Hassane Moussa Konaté 《Natural Resources》 2024年第1期28-50,共23页
The Boulon Djounga eastern perimeter is part of the Tiawa operating permit of the Société des Mines du Liptako (SML), located in the central southwestern part of Liptako (Niger). In this study, we used field... The Boulon Djounga eastern perimeter is part of the Tiawa operating permit of the Société des Mines du Liptako (SML), located in the central southwestern part of Liptako (Niger). In this study, we used field data, Reverse Circulation (RC) surveys and chemical analyzes of gold to determine the characteristics of gold and its mineralization style. The eastern perimeter of Boulon Djounga is represented by a succession of metabasalts and metasediments both intersected by intrusions of quartz and dolerite dykes, and covered by sandstone and clayey rocks. Gold is present in low contents (0.00 - 0.30 ppm) in the sedimentary cover and in medium (0.30 - 1.00 ppm) or high contents (1.00 - 4.534 ppm) in the metasediments, and in the gray quartz veins and locally in the volcanics. It exists in a disseminated state or in a concentrated state in the surrounding areas in the form of discrete grains associated with sulphurous minerals (pyrite: FeS<sub>2</sub>, chalcopyrite: CuFeS<sub>2</sub> or arsenopyrite: FeAsS). The presence of gold in the quartz veins, and the NE-SW and NW-SE orientations of the ore bodies suggest that the eastern Boulon Djounga gold mineralization would be established during a late magmatic extensive phase. 展开更多
关键词 Liptako gold Mineralization Metasediments-Volcanics Quartz Veins Sulphurous Minerals NIGER
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激光诱导击穿光谱的Gold去卷积算法自动寻峰 被引量:3
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作者 王永祥 姚明印 陈万钧 《量子电子学报》 CAS CSCD 北大核心 2023年第6期816-826,共11页
为提高激光诱导击穿光谱(LIBS)寻峰中重叠谱的分辨能力并抑制随机噪声的干扰,提出用Gold去卷积算法结合平滑处理的自动寻峰方法。对于标准样品NIST 1256b和NIST 1762的LIBS光谱,先进行平滑处理,然后采用高斯形系统函数去卷积,最后用五... 为提高激光诱导击穿光谱(LIBS)寻峰中重叠谱的分辨能力并抑制随机噪声的干扰,提出用Gold去卷积算法结合平滑处理的自动寻峰方法。对于标准样品NIST 1256b和NIST 1762的LIBS光谱,先进行平滑处理,然后采用高斯形系统函数去卷积,最后用五点法对去卷积结果进行自动寻峰。实验研究了平滑处理结合不同半峰全宽(FWHM)的系统函数对重叠峰分辨能力和抗随机噪声干扰能力的影响。结果表明,采用0.140 nm(比弱峰的FWHM稍大)作为Gold去卷积系统函数的FWHM,结合平滑处理能取得高达0.039 nm的重叠谱分辨能力,且寻峰峰位、峰值、曲线拟合与NIST数据库的数据都能较好地吻合。研究初步表明基于Gold去卷积算法的自动寻峰可应用于LIBS数据处理。 展开更多
关键词 光谱学 光谱自动寻峰 激光诱导击穿光谱 gold去卷积算法 重叠峰分辨
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GOLD标准和一秒率正常值低限对慢性阻塞性肺疾病的诊断和预后价值 被引量:2
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作者 王航 杨庆斌 《临床肺科杂志》 2023年第7期989-993,共5页
目的评估GOLD标准和一秒率正常值低限(LLN)对慢性阻塞性肺疾病(COPD)的诊断和预后价值。方法选取2018年1月~2020年6月诊治的患者202例,以专家小组诊断作为参照,使用GOLD和LLN计算COPD患病率,比较不同定义的敏感度、特异度、阳性预测值... 目的评估GOLD标准和一秒率正常值低限(LLN)对慢性阻塞性肺疾病(COPD)的诊断和预后价值。方法选取2018年1月~2020年6月诊治的患者202例,以专家小组诊断作为参照,使用GOLD和LLN计算COPD患病率,比较不同定义的敏感度、特异度、阳性预测值和阴性预测值以及kappa(κ)统计量。ROC曲线检验不同PFT参数根据参考标准预测COPD的诊断能力。共随访2年,单变量Cox回归计算不同结局的预后分析。结果专家小组诊断COPD 123例,与之相比GOLD错分33例(16.34%),两种LLN分别错分49例(24.26%)和54例(26.73%)。GOLD定义假阳性更多,LLN定义假阴性更多。专家小组诊断对患者病情加重(HR:3.978,95%CI:2.142~4.148,P<0.001)、COPD住院(HR:3.039,95%CI:1.187~4.499,P<0.001)和全因死亡(HR:3.593,95%CI:1.825~7.079,P<0.001)的判断能力强于GOLD和LLN。在GOLD或LLN中加入FEV 1%预计值和RV/TLC%预计值误诊率显著降低。结论GOLD对COPD存在过度诊断,而LLN对老年患者的COPD诊断不足。将FEV 1%预计值和RV/TLC%预计值纳入GOLD和LLN可使其更接近专家小组诊断和日常临床实践。 展开更多
关键词 慢性阻塞性肺疾病 正常值低限 慢性阻塞性肺疾病全球倡议 临床诊断 预后评估
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右江盆地卡林型金矿成矿年代学研究进展 被引量:1
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作者 高伟 胡瑞忠 +2 位作者 李秋立 刘建中 李献华 《地学前缘》 EI CAS CSCD 北大核心 2024年第1期267-283,共17页
右江盆地是全球仅次于美国内华达地区的第二大卡林型金矿床集中分布区。由于成矿时代的不确定性,盆地内卡林型金矿床的成矿动力学背景一直不清。为准确确定这些金矿床的成矿时代,近四十年来国内外矿床学家进行了孜孜不倦的探索,从早期... 右江盆地是全球仅次于美国内华达地区的第二大卡林型金矿床集中分布区。由于成矿时代的不确定性,盆地内卡林型金矿床的成矿动力学背景一直不清。为准确确定这些金矿床的成矿时代,近四十年来国内外矿床学家进行了孜孜不倦的探索,从早期以石英裂变径迹和流体包裹体Rb-Sr等时线法为代表的定年,到中期以硫化物Re-Os等时线法为代表的单矿物溶样法定年,再到最新以热液金红石、独居石和磷灰石U-Th-Pb法为代表的微区原位定年,其定年对象和方法见证了同位素地质年代学的发展历程。现已基本明确,右江盆地主要发育两期卡林型金矿成矿作用,分别为215~200 Ma和155~140 Ma,相当于印支期和燕山期,其动力学背景分别对应于印支-华南-华北地块碰撞后的印支期陆内造山过程以及燕山期软流圈上涌诱发的岩石圈伸展作用。 展开更多
关键词 右江盆地 卡林型金矿 成矿时代 印支期和燕山期成矿
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吡虫啉和啶虫脒胶体金免疫层析法试纸条性能评估及应用效果探究 被引量:1
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作者 王彧婕 冯德建 +5 位作者 冯双 侯晓妮 刘明东 吴微 周李华 李怀平 《食品安全质量检测学报》 CAS 2024年第3期133-140,共8页
目的研究吡虫啉和啶虫脒胶体金免疫层析法试纸条在不同基质中残留量检测的应用效果。方法实验考察了市场上主要流通的5种不同品牌的胶体金免疫层析法试纸条在蔬菜、水果和茶鲜叶基质中的检出限、灵敏度、交叉反应率、特异性、假阳性和... 目的研究吡虫啉和啶虫脒胶体金免疫层析法试纸条在不同基质中残留量检测的应用效果。方法实验考察了市场上主要流通的5种不同品牌的胶体金免疫层析法试纸条在蔬菜、水果和茶鲜叶基质中的检出限、灵敏度、交叉反应率、特异性、假阳性和假阴性率。结果各品牌胶体金试纸条在3种不同类型基质(白菜、苹果和茶鲜叶)中,检出限浓度水平有假阴性出现,其余浓度水平灵敏度较好;特异性和交叉反应性,结果均为阴性;假阳性率和假阴性率考察中,假阳性率为0%,但有假阴性情况出现。结论胶体金免疫层析法在检测吡虫啉、啶虫脒农药残留时具有简便快捷的特点,在蔬菜、水果基质的检测中,判定结果较为准确可靠;在茶叶基质中,由于基质效应的影响,出现假阴性的机率较高。 展开更多
关键词 吡虫啉 啶虫脒 胶体金免疫层析法 快速检测
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胶东盘子涧金矿床成矿流体特征--来自包裹体、H-O同位素证据 被引量:1
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作者 智云宝 王英鹏 +7 位作者 范海滨 王巧云 董健 马莉 谢颂诗 郝兴中 刘芳 李瑞翔 《地质论评》 CAS CSCD 北大核心 2024年第2期529-540,共12页
盘子涧金矿床地处华北板块胶辽隆起区,栖霞—蓬莱金成矿带上。金矿的形成主要与区内控矿断裂——盘子涧断裂和中生代岩浆岩有关。为研究该矿床成矿流体性质及演化,并控讨矿床成因,对该矿床不同阶段的包裹体进行岩相学、显微测温、包裹... 盘子涧金矿床地处华北板块胶辽隆起区,栖霞—蓬莱金成矿带上。金矿的形成主要与区内控矿断裂——盘子涧断裂和中生代岩浆岩有关。为研究该矿床成矿流体性质及演化,并控讨矿床成因,对该矿床不同阶段的包裹体进行岩相学、显微测温、包裹体激光拉曼及H—O同位素分析研究。盘子涧金矿床成矿热液期可划分为4个成矿阶段,从早到晚分别是黄铁矿—石英阶段(Ⅰ阶段)、石英—黄铁矿(绢云母)阶段(Ⅱ阶段)、金—石英—多金属硫化物阶段(Ⅲ阶段)和石英—碳酸盐阶段(Ⅳ阶段)。其中Ⅱ、III阶段为主成矿阶段。不同成矿阶段的流体包裹体有3种类型,分别是富液气液两相盐水包裹体、含CO_(2)三相包裹体和纯液相包裹体。显微测温结果显示,成矿流体的完全均一温度介于142~348℃,主要集中于200~300℃,盐度介于4.44%~10.98%NaCl_(eqv)。石英的δD_(V-SMOW)值为-74.6‰~-68.5‰,δ^(18)O_(V-SMOW)值为+11.65‰~+13.92‰。显示成矿流体为中低温、低盐度的CO_(2)—H_(2)O—NaCl体系,来源于地幔,以岩浆热液为主,并伴有部分大气降水加入。矿床成因类型属石英脉型金矿。 展开更多
关键词 盘子涧金矿床 流体包裹体 H—O同位素 胶东
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Development and Application of Water Quality Index (WQI) for the Evaluation of the Physico-Chemical Quality of Groundwater in Gold Mining Areas of Southeastern Senegal
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作者 Mor Diop Ibrahima Mall +3 位作者 El Hadji Mamadou Sonko Tidiane Diop Liengsy Badji Cheikh Mbow 《Journal of Water Resource and Protection》 CAS 2023年第2期33-50,共18页
Water is the most essential requirement for life. It provides a variety of purposes such as a source of water supply for drinking, domestic and industrial use, irrigated agriculture, livestock, and mining activities. ... Water is the most essential requirement for life. It provides a variety of purposes such as a source of water supply for drinking, domestic and industrial use, irrigated agriculture, livestock, and mining activities. Evaluating the status of water quality from traditional approaches does not guarantee the whole overview of the water quality situation. Therefore, developing a tool that can convert multiple parameters data into information that is understandable by both technical and non-technical personnel is vital. In this context, the purpose of this paper was to develop, calculate, and apply a water quality index for assessing the suitability (for drinking purposes) of groundwater in the gold mining areas in south-eastern Senegal. The development of this index based on WHO water quality guidelines followed the five standards steps i.e., parameters selection, sub-index formation, parameters weighting and sub-index aggregation and evaluation. Finally, the WQI summarized twelve key water quality parameters into 05 simple terms (excellent, good, medium, poor, and very poor) which is more relevant for reporting to managers and the public in a consistent manner. Thus, it was observed in the study area, that the water quality indexes in artisanal and industrial mining areas are either poor or very poor while in the reference stations (where there are no mining activities) WQI are either good or excellent. This situation was attributed to the effects of mining activities in such zones which contribute to the pollution of groundwater with heavy metals, nitrates, and suspended solids. 展开更多
关键词 Water Quality Index GROUNDWATER gold Mining POLLUTION Heavy Metals
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Deciding the Gold Standard for Oral Anticoagulation Therapy
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作者 Josh Fenn 《World Journal of Cardiovascular Diseases》 CAS 2023年第3期170-180,共11页
Healthcare practitioners have many anticoagulant options for treating various disease states pertaining to blood clots and blood clot formation. Each anticoagulant has pros and cons and the decision of which pharmacol... Healthcare practitioners have many anticoagulant options for treating various disease states pertaining to blood clots and blood clot formation. Each anticoagulant has pros and cons and the decision of which pharmacological agent to use can be confusing and difficult. In years past, Vitamin K antagonists have been the standard of care when treating specific disease states such as atrial fibrillation and venous thromboembolism based on habit and cost of care. The emergence of newer anticoagulants should be considered the new standard of care based on the evidence presented over the last several years. 展开更多
关键词 Oral Anticoagulation NOAC VKA gold Standard RIVAROXABAN AC Therapy
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Characterization of Gold Bearing Placers and Associated Minerals in the Elogo Region (North-West Congo Republic)
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作者 Noël Watha-Ndoudy Prince Espoire Wamene Okoumel +7 位作者 Timothée Miyouna Renaud Hermann Assouka Mpika Eddy Guembou Massala Guichel Souaty Mibantsa Kester Mayenga Joseph Victor Hell Boniface Kankeu Florent Boudzoumou 《Open Journal of Geology》 CAS 2023年第5期287-305,共19页
The Elogo region has been subjected to craft industry and semi-industrial mining for gold-bearing placers, since the colonial times. It is actually undergoing an intensive exploration for a primary gold deposit. The g... The Elogo region has been subjected to craft industry and semi-industrial mining for gold-bearing placers, since the colonial times. It is actually undergoing an intensive exploration for a primary gold deposit. The goal of this study is to contribute to the exploration of the primary gold deposit in the Elogo Region (North-West of Congo Republic). The methodology consisted of characterization of placers deposits by their lithology, mineralogy and the gold grains shape, in order to constrain the source of gold with the respect to the local geology. The results obtained show that alluviums are polygenic and yields seventeen mineral species composed of zircon, olivine, magnetite, ilmenite, gold, garnet, rutile, coltan, cassiterite, monazite, apatite, amphibole, tourmaline, pyrite, limonite, chromite, and amphibole. The morphoscopy of gold grain shows single grains and grains with quartz inclusions that suggest their relationship with quartz veins. The gold grains are flattened, sub-flattened, and rounded. The northern region of Elogo characterized by a dominance of coarser quartz-included gold grains indicates a proximal proparte origin (less than 50 m), while the southern region, showing less coarse and more evolved grains with choc marks, appears to be associated with a distal pro-parte origin (more than 300 m). The multivariate statistical analysis shows seven classes of samples corresponding to the mineralogical paragenesis suggesting various sources, consisting of high-grade metamorphic, granitoids, pegmatites, basic and ultrabasic rocks, and BIFs that provided minerals to the placers. Gold mainly comes from hydrothermal quartz veins and probably from the peptization of gold from the weathering of sulfides occurring in the BIF. In the Elogo region, gold exploration for primary deposits should look for and follow the hydrothermal system developed in this region. Chemical analysis for the gold grains and associated minerals is necessary to better guide the proposed geochemical prospecting. 展开更多
关键词 Auriferous Placers Associated Minerals Correspondence Factor Analysis Principal Component Analysis Elogo gold Exploration
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Quantitative Easing: Money Supply and Commodity Prices of Oil, Gold, and Cocoa in Ghana
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作者 Samuel Kwaku Obeng Samuel Bassah Kofi Quansah +3 位作者 Theresa Dowetin Ampem Darko Nsiah Ezekiel Nii Noye Nortey Ebenezer Okyere 《Open Journal of Statistics》 2023年第5期663-693,共31页
This study investigates the dynamic relationships between the money supply (M2) and key commodity prices (Cocoa, Gold, and Crude) in the context of Ghana. Utilizing Vector Error Correction Model (VECM) analysis, we an... This study investigates the dynamic relationships between the money supply (M2) and key commodity prices (Cocoa, Gold, and Crude) in the context of Ghana. Utilizing Vector Error Correction Model (VECM) analysis, we analyze the short-term and long-term Granger causality relationships among these variables, aiming to shed light on the potential linkages between monetary policy and commodity markets. The analysis covers the period from December 1999 to April 2023, using lag structures of 1 and 8 to capture both short-term and more enduring effects. Our findings reveal significant Granger causality relationships between the money supply and various commodities, with nuanced patterns emerging across different lags. In the short-run, our results suggest bidirectional causal relationships between COCOA and M2, CRUDE and M2, and GOLD and M2. Additionally, M2 Granger causes changes in COCOA, CRUDE, and GOLD. However, the causal relationship between COCOA and GOLD appears to be unidirectional, with COCOA not significantly Granger causing changes in GOLD. The short-term findings highlight the intricate interplay between monetary policy and commodity markets. In the long-run (lag 8), our analysis unveils robust Granger causality relationships between the variables. Past values of COCOA, CRUDE, and GOLD Granger cause changes in M2, indicating a notable influence of commodity markets on the money supply. Similarly, M2 Granger causes changes in CRUDE and GOLD. Notably, the findings underscore a more comprehensive and intertwined relationship between monetary policy and commodity prices in the long-run. Based on these results, we derive several policy implications. Policymakers should carefully consider the potential impact of monetary policy decisions, such as quantitative easing, on commodity markets and price dynamics. Measures to stabilize commodity prices, promote export diversification, manage inflation expectations, and enhance economic resilience are recommended. Additionally, effective data monitoring, international collaboration, and proactive risk management strategies are essential components for navigating the complex interactions between monetary policy and commodity markets. This study contributes to a deeper understanding of the intricate connections between monetary policy and commodity prices in Ghana, offering insights for policymakers, researchers, and stakeholders seeking to promote sustainable economic growth and stability. Further research can delve into the mechanisms underlying these relationships and explore their broader implications for trade balances, economic performance, and policy formulation. 展开更多
关键词 Quantitative Easing Money Supply Cocoa gold CRUDE VECM
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Alteration Typology and Geochemical Signatures of the Napélépéra Gold-Bearing Granodiorite in South-West Burkina Faso (West Africa)
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作者 Théophile Ouédraogo Sâga Sawadogo +1 位作者 Hermann Ilboudo Séta Naba 《Open Journal of Geology》 2023年第10期1162-1175,共14页
The characterization of the relationships between mineralization and hydrothermal alteration is an essential element in understanding gold deposits. In south-west Burkina Faso, the Napélépéra mineralisa... The characterization of the relationships between mineralization and hydrothermal alteration is an essential element in understanding gold deposits. In south-west Burkina Faso, the Napélépéra mineralisation, the mobility of chemical elements and alteration-mineralization relationships were studied by means of selected core drilling and geochemical analyses using ICP-MS (Inductively Coupled Plasma Mass Spectrometry) and ICP-AES (Inductively coupled plasma atomic emission spectroscopy). The mineralised granodiorite is grey porphyroid with quartz, plagioclase, biotite and amphibole. It is metaluminous and located in the tholeiitic series. The Na<sub>2</sub>O + CaO versus Fe<sub>2</sub>O<sub>3</sub> + MgO alteration diagram divides the samples according to alteration dominance. Chloritisation and carbonation are the main alterations. There is a relationship between gold mineralisation at Napélépéra and alteration, and the paragenesis of gold + pyrite ± carbonate ± silica ± sericite is the main characteristic. Carbonation is the result of fluid input in the shear corridor of the mineralised zone. The mass balance of comparative metals in the proximal and distal zones of the mineralisation shows the absence of metals, while As, Hg, Ag and Bi are strongly enriched from the distal zone to the mineralised zone. The oxides associated with the mineralisation are mainly NaO, SrO and CaO. 展开更多
关键词 gold Mineralization ALTERATION Mass Balance Granodiorite
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Appropriateness of Reduced Modified Three-Parameter Weibull Distribution Function for Predicting Gold Production in Ghana
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作者 Samuel Kwaku Obeng Christiana C. Nyarko +1 位作者 Lewis Brew Kaku Sagary Nokoe 《Open Journal of Endocrine and Metabolic Diseases》 2023年第4期534-566,共33页
Forecasting mine production is pertinent to gold mining as it serves as production goals for investors. It is therefore important to identify the exact distribution that gold production as a response variable naturall... Forecasting mine production is pertinent to gold mining as it serves as production goals for investors. It is therefore important to identify the exact distribution that gold production as a response variable naturally follows. It is even more appropriate to have a model(s) with few predictor variables. This paper seeks to identify appropriate statistical distribution functions for fitting gold production in Ghana. The empirical paper relied mainly on quarterly secondary datasets on gold production between the years 2009 and 2022 secured from the Minerals Commission of Ghana, Accra. Several known statistical distributions including Weibull, Log-Normal, Generalized Extreme Value (GEV) were explored with Maximum Likelihood Estimation (MLE) and evaluated using model selection criteria as AIC, AICc and BIC. Goodness of Fits were evaluated using Kolmogorov-Smirnov Test (K-S), Cramer-Von Mises Statistic and Anderson-Darling Statistic. Based on the analysis conducted, the reduced modified 3-parameter Weibull distribution provided the best fit for gold production in Ghana. Though the reduced modified Weibull function is proposed, it is important however to recognize that other external factors can influence production levels. Also, the average quarterly fitted gold production is 1000334.8918 ± 75,327.080 (±7.5%) [i.e., 925,007.812 – 1,075,661.972]. This indicates that the average annually fitted gold production lies between 3700031.248 and 4302647.888 ounces at 99.9% confidence level. Therefore, the predicted gold production for the year 2022 is 3.7million ounces at 99.9% confidence level. 展开更多
关键词 gold Production Statistical Distribution Functions Goodness of Fit Statistics
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