花岗岩Sn-W-Nb-Ta-Rb-Cs-Li成矿作用的研究方法——以滇西南大同山稀土矿区土壤化探异常查证为例

滇西南大同山稀土矿区位于临沧花岗岩中南段,基岩主要为三叠纪黑云母二长花岗岩,属“S”型花岗岩,形成于同碰撞环境。临沧花岗岩分布区为Sn、W、Bi、B、Li、Rb、Cs、Pb、As、Sb高丰度区,在矿区内La-Y-Nb组合异常,但未进行检查。在矿区1∶50 000土壤地球化学调查中,圈定了16个综合异常。异常查证中,在13个综合异常区的半风化—微风化花岗岩中共采集19件化学分析样,分析了与综合异常相关的7种元素(Sn、W、Nb、Ta、Rb、Cs、Li)。本研究中总结了4种方法:(1)经岩石类型分析数值比较,除中粗粒黑云母二长花岗岩(ηγ^(c)T)与Cs_(2)O矿化有较密切关系外,其他岩石类型与矿化无明显关系;(2)通过样品分析数值比较,将样品划分为矿化元素、矿化程度不同的4种类型;(3)通过矿化系数分析,矿区可能存在Sn-W矿化、Rb-Cs矿化;(4)通过成矿系数分析,矿种的平均成矿系数由大至小为Rb_(2)O(0.6929)→Nb_(2)O_(5)(0.1445)→Cs_(2)O(0.0626)→Ta_(2)O_(5)(0.0378)→WO_(3 )(0.0195)→Sn(0.0101)→Li_(2)O(0.0098)。这4种研究方法对研究临沧花岗岩的成矿作用、进行成矿预测有较为重要的指导作用。在地质背景相似的地区寻找相似矿种,也可借鉴本文提出的研究方法。

地球化学勘探与矿化特征分析在找矿中的整合与创新

地球化学勘探和矿化特征分析是矿产资源勘探中的两个重要领域,它们的整合与创新在矿产资源的开发与利用中具有重要意义。本文从理论基础、技术方法和实际案例等方面探讨了地球化学勘探与矿化特征分析的整合与创新。

金川铜镍矿床I矿区地质体三维建模与矿化空间分析

文章利用三维建模技术对金川铜镍矿床I矿区进行建模,在此基础上分析了矿体的矿化结构。根据钻孔柱状图和各时期地质勘探报告中相关数据建立了地质数据库,利用ArcGIS,GOCAD,Datamine软件建立了金川铜镍矿床I矿区矿体的三维实体模型、矿体块体模型、地层模型和断层模型;运用地质统计学原理,在Surpac中对Cu、Ni品位空间变化结构进行了分析,得到空间变异椭球体模型,实现了金川I矿区Cu、Ni品位变化形态的空间分布展示;得出矿化空间分布规律。

蒙亚啊铅锌矿床矿化过程分析

西藏蒙亚啊铅锌矿床位于隆格尔-念青唐古拉断隆带东段,是典型的矽卡岩矿床。区域地层齐全,矿体主要呈层状产出,矿区来姑组(C2P1l)地层为主要赋矿地层。矿体主要呈层状、似层状产出,受断裂构造控制明显,以东西向及南北向断裂为主。本文在详细掌握蒙亚啊矿床地质特征的基础上,利用岩石学、矿石学、矿床学、岩石地球化学、矿物学等手段,研究了蒙亚啊矿床的矿物共生组合,分析了矿床蚀变分带特征及矿化特征,通过对矽卡岩矿物及金属硫化物成分的确定,分析了矿床形成过程中的环境变化,通过对该矿床的矿区特征,矿物特征进行详细分析,以及矿物成分、矿物组合及关系分析矿床矿化过程。

基于地质统计学与Surpac软件的夏甸金矿区矿化空间分析

矿区外围及深部的成矿预测需要对老矿区矿化空间分布进行定性分析,提取最有利的矿化指标,为控矿规律分析和成矿区圈定提供技术支持。文章以山东夏甸金矿床Ⅶ号矿体群为例,利用Surpac软件建立该矿区地质数据库,进行实验变异函数的计算与理论变异函数拟合,通过交叉验证,获取最优的搜索椭球体参数,构建搜索椭球体模型,揭示出矿体的矿化分布规律,最后在各三维坐标轴平面绘制矿化投影等值线图,直观地展示矿体内部金品位的连续方向,为矿化指标计算提供数据支撑。

矿床矿化特征分析软件设计与实现

对矿床矿化特征软件进行需求分析,并分别分析矿床矿化特征在单元素和多元素环境下的不同的功能需求;然后对矿床矿化特征分析软件进行总体结构设计;利用C#编程嵌入Excel中运行,实现单元素和多元素矿床矿化特征分析的具体功能,包括设置第一,二,三分界点,规范化赋值,计算变化性,不连续系数,矿化率,围岩化,离散系数等,并一键生成Excel统计表格;开发的软件经过测试运行,人机交互友好,操作简便,功能齐全,计算准确。

湖南省川口矿田黑钨矿床成矿规律分析及找矿靶区预测研究

川口矿田位于东南地洼区赣桂地洼系,地处衡阳地洼与茶陵地洼之间近南北向川口隆起的南缘,为耒临南北向构造与浏衡北东向构造叠加复合部位。矿床成矿作用主要与燕山期花岗岩有关,矿化主要集中于花岗岩与新元古界板溪群的内接触带、外接触带,矿体的产出受接触带及岩浆岩同生破裂构造(断裂及节理)控制,接触带控制矿化总体展布,岩浆岩同生破裂构造是单个矿体的重要构造之一。该矿床与华南地区的其他大多矿床成矿模式相比有所不同,不具备"五层楼模式",矿化显示出逆向分带特征。基于已有资料,结合本区地质成矿特征,圈定了三个找矿靶区。

青龙满族自治县一带铁矿资源分布特征及远景评价初识

研究区铁矿位于青龙满族自治县,其沉积变质型铁矿成矿带的西北段,产于志留系温泉沟组海相碎屑-碳酸盐沉积浅变质岩层内,赋矿岩性为白色白云质大理岩、灰色-灰黑色大理岩化灰岩、钙质砂岩,受沉积层位控制。本文主要从区域地质、矿区地质、矿(化)体特征等方面进行分析,认为该铁矿床属沉积变质菱铁矿型铁矿床和构造热液成因菱铁矿,综合对该区地质特征进行分析和研究。

Apparent activation energy for spontaneous combustion of sulfide concentrates in storage yard

In order to evaluate the spontaneous combustion hazard of sulfide concentrates in storage, three different kinds of sulfide concentrates （sulfur-rich sulfide concentrate, iron sulfide concentrate and copper sulfide concentrate） were obtained from a storage yard in Dongguashan Copper Mine, China. The reaction processes at different heating rates of 5, 10, 15, 20, and 25 ℃/min in air flow from ambient temperature to 1 000 ℃ were studied by TG-DTG-DSC analysis. By the peak temperatures of DTG curves, the whole reaction process for each sample was divided into different stages, and the corresponding apparent activation energies were calculated by the Ozawa-Flynn-Wall method. It is found that the reaction process of each sample is considerably complex; the apparent activation energy values change from 36 to 160 kJ/mol in different temperature ranges; sulfur-rich sulfide and iron sulfide concentrates have lower apparent activation energy than copper sulfide concentrate below 150 ℃; so they are more inclined to cause spontaneous combustion at ambient temperature.

甘肃北山地区岩石磁组构特征及其构造意义

甘肃北山地区岩石磁组构特征是磁各向异性度P值大,反映该区总体韧性剪切变形强烈磁椭球扁率E＞0占优势,磁面理发育,部分样品磁线理发育,反映变形以压扁变形为主;但局部剪切拉伸变形明显,最小磁化率轴投影显示变形主压应力为近南北向为主.矿化蚀变的糜棱岩中P值与金品位呈反相关,说明矿化蚀变的热液作用削弱了岩石中已经形成的磁化率各向异性,反映出矿化蚀变晚于构造变形的时序关系.这与该区处于塔-哈两板块碰撞带的大地构造位置以及碰撞带的变形性质、变形样式、变形动力学和运动学,以及成矿作用的特点是相吻合的.

Characterization of an iron oxy/hydroxide(gossan type) bearing refractory gold and silver ore by diagnostic leaching

A detailed characterization of an iron oxy/hydroxide(gossan type) bearing refractory gold/silver ore was performed with a new diagnostic approach for the development of a pretreatment process prior to cyanide leaching. Gold was observed to be present as native and electrum(6-24 μm in size) and associated with limonite, goethite and lepidocrocite within calcite and quartz matrix. Mineral liberation analysis(MLA) showed that electrum is found as free grains and in association with beudantite, limonite/goethite and quartz. Silver was mainly present as acanthite(Ag2S) and electrum and as inclusions within beudantite phase in the ore. The cyanide leaching tests showed that the extractions of gold and silver from the ore(d80: 50 μm) were limited to 76% and 23%, respectively, over a leaching period of 24 h. Diagnostic leaching tests coupled with the detailed mineralogical analysis of the ore suggest that the refractory gold and silver are mainly associated within iron oxide mineral phases such as limonite/goethite and jarosite-beudantite, which can be decomposed in alkaline solutions. Based on these characterizations, alkaline pretreatment of ore in potassium hydroxide solution was performed prior to cyanidation, which improved significantly the extraction of silver and gold up to 87% Ag and 90% Au. These findings suggest that alkaline leaching can be used as a new diagnostic approach to characterize the refractoriness of iron oxy/hydroxide bearing gold/silver ore and as a pretreatment method to overcome the refractoriness.

Reactivities of Shenfu Chars Toward Gasification with Carbon Dioxide

Five Shenfu char samples were prepared from Shenfu raw coal at different temperatures （950, 1100, 1200, 1300 and 1400℃） using a muffle furnace. Demineralization of the char samples was performed by treating them with 10% nitric acid for 10 min in a CEM Discover microwave reactor. The gasification of the chars, and corresponding demineralized chars, in a carbon dioxide （CO2） atmosphere was conducted in a Netzsch STA 409Cl31F tempera- ture-programmed thermogravimetry apparatus. The effects of charring temperature and demineralization on the gasification reactivity of chars were systematically investigated. The results show that a char formed at a lower temperature is more reactive except for demineralized char formed at 1100℃, which is less reactive than char formed at 1200℃. Demineralization decreases the char reactivities toward gasification with CO2 to a small extent.

Effect of sodium pyrophosphate on the flotation separation of chalcopyrite from galena

The effect of sodium pyrophosphate （SPH） on the separation of chalcopyrite from galena was examined through flotation, adsorption, electrokinetic studies and infrared spectral analysis. Differential flotation tests indicate that satisfactory separation can be achieved within the pH range from 2.5 to 6 using SPH to depress the galena, but not the chalcopyrite when O-isopropyl-N-ethyl thionocarbamate （IPETC） is used as the collector. The electrophoretic mohilities of both the minerals dramatically become negatively charged following SPH adsorption in the pH range from 2.5 to 12, The infrared spectral analysis suggests that chemical adsorption occurs on galena surface treated by SPH, indicating that a chelate complex has formed. At weakly acidic pH values, the adsorption density of IPETC onto galena is significantly reduced in the presence of SPH. However, the amount of IPETC adsorbed onto chalcopyrite almost remains at the same level. Since the observed adsorption density of IEPTC onto chalcopyrite is quite high compared to galena, the observed flotation results are explained. A possible mechanism for the interaction between the two sulphide minerals and SPH is discussed.

Galena-pyrolusite co-extraction in sodium chloride solution and its electrochemical analysis

The co-extraction behavior of galena-pyrolusite in a sodium chloride solution and the electrochemical mechanism of this process were investigated,and some factors affecting the leaching rate of Pb and Mn were optimized.The results show that all the factors such as the concentration of NaCl,HCl and pyrolusite ore,reaction time,temperature,adding times of HCl,affect the leaching rate of Pb.The main affecting factors are the concentration of NaCl,reaction time and temperature.The Tafel polarization curves and EIS plots of the galena and pyrolusite in the NaCl solution demonstrate that during the oxidation process of galena mineral electrode,film forms on the galena surface,which prevents galena from deeper oxidation.However,the film resistance can be greatly reduced in the presence of sodium chloride,thus promoting the reaction rate of galena.

Oxidation behaviour and phase characterization of titaniferous magnetite ore of eastern India

Titaniferous magnetite ore is a kind of symbiotic complex ore which comprises ilmenite, magnetite, hercynite and magnesio-hercynite spinel minerals. The ore collected from eastern India was characterized by XRD, WDXRF, SEM and M？ssbauer spectroscopy. The oxidation behaviour of fine ore was investigated by TG-DTA analysis under oxygen atmosphere. Subsequent isothermal oxidation experiments were carried out under oxygen and air atmospheres, holding the samples for different periods of time at different temperatures from 873 K to 1473 K. It was observed that ilmenite phase transformed to hematite and titanium dioxide at lower temperature, whereas ferric-pseudobrookite phase was found at higher temperature. Direct reduction of oxidized sample-coke cylindrical briquettes was successfully achieved for phase transition from titaniferous magnetite to iron and titanium dioxide at 1473 K.

Separation and analysis of aromatic hydrocarbons from two Chinese coals

Separation and analysis of aromatic hydrocarbons (AHs) from coals is of considerable significance for both fuel and non-fuel use of the coals. In present work two Chinese bituminous coals were selected for separation of AHs by ultrasonic extrac-tion with CS2 followed by column chromatography using hexane as eluent. A series of AHs were separated from the two coals and analyzed by GC/MS. FTIR was employed to characterize the raw coals and the extracted residues. The results of GC/MS analysis show that the separated AHs are mono- to tetracyclic arenes, among which the principle AHs are alkyl naphthalenes and phenan-threnes. Obvious differences in the composition and the structure of AHs exist between the two coals, i.e., the AHs from Tongting coal tend to be higher rings compared to those from Pingshuo coal both from the variety and from the abundance of the AHs. FTIR analysis shows that the raw and extracted coals are similar in terms of functional groups, suggesting that the composition and structure of CS2 extract, especially the AHs, from coals can be used to interpret the coal structure to some extent.

Chemical, physical, thermal, textural and mineralogical studies of natural iron ores from Odisha and Chhattisgarh regions, India

The chemical,physical,thermal and texture properties of iron ores from different regions of Odisha and Chhattisgarh regions,India,have been investigated to understand the compositional variations of Fe,Al2O3,SiO2,S and P.They were analyzed for its susceptibility to meet the industrial requirements,for various iron manufacture techniques.Chemical analysis indicated that the majority of the iron ores is rich in hematite(>90wt%),poor in gangue(<4.09wt%SiO2and<3.8wt%Al2O3)and deleterious elements(P<0.065wt%and S<0.016wt%)in all these iron ores found to be low.XRD peaks reviled that the gangue is in the form of kaolinite and quartz,and same was observed in Fourier transform infrared(FTIR)spectroscopy in the range of914to1034cm–1.The iron ores were found to have excellent physical properties exemplify with tumbler index(82wt%–91wt%),abrasion index(1.27wt%–4.87wt%)and shatter index(0.87wt%–1.64wt%).FTIR and thermal analysis were performed to assimilate the analysis interpolations.It was found that these iron ores exhibit three endothermic reactions,which are dehydration below447K with mass loss of0.13wt%to1.7wt%,dehydroxylation at525–609K with mass loss of1.09wt%–4.49wt%and decomposition of aluminosilicates at597–850K with mass loss of0.13wt%–1.15wt%.From this study,we can conclude that due to its excellent physico-chemical characteristics,these iron ores are suitable for BF and DRI operations.

Nutritional quality, functional properties and anti-nutrient compositions of the larva of Cirina forda (Westwood) (Lepidoptera: Saturniidae)

Determination of the proximate, nutritionally valuable minerals and anti-nutrient compositions in larvae of Cirina forda (W) showed that they contained high levels of protein, (55.50%±1.20%) with ash, moisture, fat, and carbohydrate levels being (10.26%±0.01%), (10.85%±0.38%), (4.68%±0.01%) and (18.70%±0.84%) respectively. Fibre was not detected. Protein solubility was higher in alkaline media than in acidic media while the isoelectric points were pH 4, 6 and 9 indicating that C. forda may be useful in food formulations involving foods like meat products. Phosphorus had the highest value of (215.54±0.21) mg/100 g while manganese had the lowest value of (1.14±0.10) mg/100 g. Copper, Co, Pb, Cr and Ni were not available. Water absorption capacity was (300%±0.15%), oil absorption capacity was (358.44%±0.21%) and foaming stability was (3%±0.00%). The results of anti-nutritional analysis revealed that oxalate and phytic acid contents were (4.11±0.05) mg/100 g and (1.02±0.00) mg/100 g respectively and that these values fell within nutritionally accepted values. Tannin was not detected in C. forda. C. forda, a rich source of animal nutrients, usable in human diets and animal feeds formulations.

Low Temperature One-Step Synthesis of Barium Titanate:Thermodynamic Modeling and Experimental Synthesis

A thermodynamic model has been developed to determine the reaction conditions favoring low temperature direct synthesis of barium titanate (BaTiO3). The method utilizes standard-state thermodynamic data for solid and aqueous species and a 0ebye-Huckel coefficients model to represent solution nonideality. The method has been used to generate phase stability diagrams that indicate the ranges of pH and reagent concentrations, for which various species predominate in the system at a given temperature. Also, yield diagrams have been constructed that indicate the concentration, pH and temperature conditions for which different yields of crystalline BaTiO3 can be obtained. The stability and yield diagrams have been used to predict the optimum synthesis conditions (e.g., reagent concentrations, pH and temperature). Subsequently, these predictions have been experimentally verified. As a result, phase-pure perovskite BaTiO3 has been obtained at temperature ranging from 55 to 85℃ using BaCl2, TiCl4 as a source for Ba and Ti, and NaOH as a precipitator.