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1.
The granites of the Ukrainian shield are secondary; the “shield,” in the first instance, is a segment of a fold belt which extends from the Black Sea, via the Voronezh Arch, to the Kola Peninsula. The metamorphic ungranitized anticlines are narrow folds in which are found iron, copper, zirconium and precious metals. Iron, titanium, copper, graphite and mica deposits are found in the folds of granitized gneisses, migmatites, anatektites and granites. The crystalline metal ores are associated with metamorphosed elastics and evaporites; the titanium, copper, cobalt, gold, vanadium, mercury, chromium and nickel deposits – associated with sedimentary volcanics and evaporites. The high-grade metamorphics Contained the deposits of titanium, iron, calcium, magnesium, copper, vanadiuta, lead and zinc. The chromites and nickel silicates are associated with the intrusives. In short, metamorphic history and mineralogy exercised a direct control over the size and grade of ore deposits.  相似文献   

2.
In order to assess pollutants and impact of environmental changes along the Egyptian Red Sea coast, seven recent and Pleistocene coral species have been analyzed for Zn, Pb, Mn, Fe, Cr, Co, Ni, and Cu. Results show that the concentration of trace elements in recent coral skeletons is higher than those of Pleistocene counterpart except for Mn and Ni. In comparison with recent worldwide reefs, the present values are less than those of Central America coast (iron), Gulf of Aqaba, Jordan (lead, copper), Gulf of Mannar, India (chromium, zinc, manganese), Costa Rica, Panama (chromium, nickel), North-west coast of Venezuela and Saudi Arabia (copper). The present values are higher than those of Gulf of Aqaba, Jordan (iron, zinc, manganese), Gulf of Mannar, India (lead, cobalt, nickel), North-west coast of Venezuela (lead, zinc, chromium, manganese), Australia (copper, nickel, zinc, manganese). The highest values were recorded in Stylophora pistillata (iron, lead and copper), Acropora cytherea (cobalt), Pocillopora verrucosa (zinc) and the lowest concentrations were recorded in Goniastrea pectinata (iron, chromium, copper and nickel), Favites pentagona (lead, zinc and manganese), and Porites lutea (cobalt). The differences in metals content among the studied species are attributed to differences in microstructure and microarchitecture.  相似文献   

3.
Water and sediment samples were collected from 20 location of the Buriganga river of Bangladesh during Summer and Winter 2009 to determine the spatial distribution, seasonal and temporal variation of different heavy metal contents. Sequential extraction procedure was employed in sediment samples for the geochemical partitioning of the metals. Total trace metal content in water and sediment samples were analyzed and compared with different standard and reference values. Concentration of total chromium, lead, cadmium, zinc, copper, nickel, cobalt and arsenic in water samples were greatly exceeded the toxicity reference values in both season. Concentration of chromium, lead, copper and nickel in sediment samples were mostly higher than that of severe effect level values, at which the sediment is considered heavily polluted. On average 72 % chromium, 92 % lead, 88 % zinc, 73 % copper, 63 % nickel and 68 % of total cobalt were associated with the first three labile sequential extraction phases, which portion is readily bioavailable and might be associated with frequent negative biological effects. Enrichment factor values demonstrated that the lead, cadmium, zinc, chromium and copper in most of the sediment samples were enriched sever to very severely. The pollution load index value for the total area was as high as 21.1 in Summer and 24.6 in Winter season; while values above one indicates progressive deterioration of the sites and estuarine quality. The extent of heavy metals pollution in the Buriganga river system implies that the condition is much frightening and may severely affect the aquatic ecology of the river.  相似文献   

4.
红格矿区是我国目前最大的钒钛磁铁矿资源基地,其矿产资源储量丰富,伴生钒、钪、镓、铬、钴、镍、铜、硫等有用元素,具有较高的经济价值。通过系统分析矿区有益元素的赋存状态及分布规律表明:矿石中各种元素的相对含量以及含量的波动幅度,与矿石TFe、岩性和岩石组合高度相关。  相似文献   

5.
 Arsenic, chromium, cobalt, copper, lead, nickel, vanadium and zinc distributions in surficial and core sediments of the Elba-Argentario marine basin (southern Tuscany, central-western Italy) are reported. Analysis of such distributions compared with grain size and mineralogical data allowed the identification of areas showing trace element enrichments with respect to natural background. These enrichments are moderate and essentially restricted to Pb and Zn; only As shows a widespread, though not high, positive anomaly. This general pattern is in good agreement with the minor industrialization affecting the basin's watershed. An unexpected anomaly, concerning Co, Pb, and As, as well as Fe and Ti, has been pointed out close to Montecristo Island. This has been ascribed to illegal local dumping of chemical waste. Received: 12 January 1996 / Accepted: 9 September 1996  相似文献   

6.
The generation of electricity has been identified as one of the main pollutant activities, and some studies have established an increment of heavy metals in soil in the areas surrounding these plants. The aim of this study was to evaluate the soil concentrations of heavy metals in the zone surrounding a thermoelectric power in Mexico. Thirty-two top soil samples (0–5 cm) were collected; additionally, four depth profiles (1 m) were investigated. Median concentrations for chromium, vanadium, nickel, mercury, and cadmium were 47, 47, 73, 0.02, and 0.01 mg/kg, respectively. Higher Cr, Ni, and V concentrations were observed in the soil depth profiles located closer to the plant in comparison with the concentrations found in the soil depth profile located further away from the plant; these results may indicate a possible accumulation of these metals. The geoaccumulation index results indicated that most of the sites were in the classifications of unpolluted and unpolluted to moderately polluted (classes 1 and 2). The statistical results showed that downwind of the plant in relation to the prevailing winds, there was a strong correlation between soil concentrations of chromium, copper, nickel, and vanadium. Based on the results of this study, it can be concluded that the use of fuel oil at the thermoelectric plant contributed to the accumulation of vanadium and nickel in the soil of the surrounding areas, as well as chromium and copper.  相似文献   

7.
The purpose of this study was to determine and assess the concentrations of trace metals in surface seawaters and sediments from different coastal habitats of the Red Sea coast of Yemen. Surface seawater and sediment samples were collected, treated and analyzed for cadmium, cobalt, manganese, chromium, lead, iron, nickel, copper, zinc and vanadium by the atomic absorption spectrometric analysis. The concentrations were high for cadmium, cobalt and lead and low or consistent with the natural background concentrations for the rest of the metals. However, the coastal habitats of the Red Sea coast of Yemen are still considered unpolluted, it is concluded that the cadmium cobalt and lead levels in surface seawaters are high and could have negative effects on marine life of the sites. Further studies are needed to characterize the sources fate, biogeochemical processes and impacts of these trace metals on coastal habitats and marine life of the region.  相似文献   

8.
西昆仑塔木-卡兰古铅锌铜成矿带上卡拉塔什矿区含铜砂页岩中发现较高含量的钴,并伴有铜、镍、铅、银等多种有益组分,原生钴矿物可能与镍一起以独立矿物形式存在。本区钴矿的容矿岩石为含铜砂页岩,成因类型可能属喷流-沉积型钴铜铅多金属矿。  相似文献   

9.
We measured the amount of arsenic, chromium, copper, lead, nickel, vanadium, and zinc accumulated over a five-year period from 1997 to 2002 in surface sediments of seven salt marshes along the New Brunswick coast of the Bay of Fundy, Canada. Study sites extended from outer to inner Bay, spanning a gradient in tidal range (6–12 m) and mean sediment deposition rate (0.27–1.76 cm yr−1). In each study site, metal concentrations were measured in low and high marsh areas. Concentrations of chromium, nickel, and zinc appear to be within their natural range, while arsenic, lead, and vanadium are enriched in some sites. Calculated sediment metal loadings rates showed variability among marsh sites that closely followed sediment deposition patterns, suggesting sediment deposition rate is the driving factor of short-term metal accumulation in Fundy marshes. The value of salt marshes as a sink for metals may be enhanced by high sedimentation rates.  相似文献   

10.
This paper presents one of the first investigations into the geochemical enrichment of the middle and lower Mvoti river system. Chemical elements are naturally present in aquatic sediments, but their concentrations tend to rise to potentially toxic levels via both natural and anthropogenic processes. This study evaluated the concentrations of aluminum, arsenic, boron, barium, cadmium, calcium, cobalt, chromium, copper, iron, lead, magnesium, manganese, molybdenum, nickel, phosphorous, selenium, silicon, strontium, titanium, vanadium and zinc, using inductively coupled plasma optical emission spectroscopy. The levels of elements present were used to assess their spatial distribution within the river and to determine the contamination factors and enrichment factors for each element. The pollution load index (PLi) is another contributing parameter that was calculated to determine the degree of pollution at each site. The results indicate that the sediments of the Mvoti are low to moderately polluted and deteriorating with time (average PLi value of 5.19), and that a major contributing factor to this contamination is natural sources.  相似文献   

11.
Stratiform quartz-sulphide lodes in Ingladhal occur in a typical Precambrian green-stone-belt environment comprising metabasalts, tuff, chert and cherty iron-sulphide formation. Unusually high cobalt contents of metavolcanics and of sulphide minerals in orebodies suggest a consanguinity between ores and rocks. 90% of total nickel, 70% of total cobalt but only 30% of total copper in rocks occur in silicate phases and thus indicate an early separation of copper from cobalt and nickel. Unusually high non-sulphide copper in barren bedded cherts implies availability of Cu-rich solution prior to their lithification. Pyrite in sediments, in volcanics, and in orebodies is characterized by a distinctive pattern of Co-Ni distribution in each case. Partitioning of Co and Ni between coexisting sulphide pairs is complex, but gross equilibrium is indicated. Very high trace metal content of orebody pyrite sharply contrasts with very low such values in pyrite from adjacent sediments and points to a higher temperature of formation of orebodies.  相似文献   

12.
The recovery of nickel, copper and cobalt from ocean manganese nodules by a segregation roasting technique was investigated under a wide range of conditions with several nodule samples all of which gave similar results. The best conditions for the segregation of the metals were achieved with CaCl2 as the chloride source at a batch retention time of approximately two hours; the highest recoveries were obtained at approximately 850°C for copper and at 1,050°C for nickel and cobalt. At 850°C, copper recovery was 75%, but nickel and cobalt recoveries were only about 25%. At 1,050°C, the nickel and cobalt recoveries were increased to about 60%, but the copper recovery dropped to only 35%. Electron-probe microanalysis showed the segregated metal to be an alloy, indicating that gaseous reactions play an important role in the reduction of chlorides to metal during the process.  相似文献   

13.
Metal levels (cadmium, cobalt, chromium, copper, iron, nickel, lead and zinc) of seventeen different edible wild fungi species (Agaricus campestris, Calocybe gambosa, Coprinus comatus, Hericium coralloides, Hydnum repandum, H. repandum var. rufescens, Lactarius deliciosus, L. salminocolor, Macrolepiota procera, Pleurotus ostreatus, P. ostreatus var. columbinus, Ramaria aurea, R. stricta, Rhizopogon luteolus, Sparassis crispa, Suillus bovinus, Tricholoma terreum) growing in Bolu-Turkey were measured by inductively coupled plasma optical emission spectrocopy. The obtained data were analyzed with “statistical package for the social sciences” statistics program. In addition, relation between metal concentrations in both soil and fungi samples were investigated. The highest metal concentrations in Bolu District, Turkey were measured in A. campestris (cadmium 0.270, chromium 2.735 and zinc 7.683), C. comatus (iron 160.12), M. procera (copper 15.990, cobalt 0.352 and nickel 3.645), R. luteolus (Pb 4.756) mg/kg dw (dry weight). As a result of the measurements, it was observed that metal uptake is related with the species of fungi and is also affected by pH and organic contents of the soil.  相似文献   

14.
江汉盐湖盆地原油中微量金属元素的分布及应用   总被引:2,自引:0,他引:2  
杨志琼  段思宏 《沉积学报》1987,5(4):137-146
利用发射光谱粉末法,定量测定江汉盐湖盆地72个原油样中的钴、锗、锆、钼、铬等13个微量金属元素后查明,这些元素在地层剖面上的分布有明显规律。除镁及铅以外,11种金属元素的含量随地层变老和原油成熟度增加而减少。如潜一段重质原油中钼、钴的含量比下伏地层高出15倍左右,锗只在潜一段原油中存在。11种元素的含量还随原油的比重、粘度、合硫量、沥青质、胶质及卟啉化合物的增加而增加。利用这些分布特点可区别不同油层的原油,也可推测油气运移的方向。  相似文献   

15.
熊英  王晓雁  胡建平 《岩矿测试》2011,30(3):299-304
文章在修订GB/T 14353—1993《铜矿石、铅矿石和锌矿石化学分析方法》研究工作中,建立了电感耦合等离子体发射光谱同时测定铜铅锌矿石中铜铅锌钴镍等元素的标准分析方法。通过控制试样量和制备试样溶液的体积,可实现主量元素铜、铅、锌与次量元素钴、镍的同时测定。测定范围为铜0.002%~8.5%,铅0.01%~5%,锌0.005%~3%,钴0.001 5%~0.5%,镍0.003%~0.5%。按照相关国家标准对测量方法与结果的准确度进行8个实验室协同参加的准确度试验,统计参数结果表明在限定水平范围内方法偏倚不显著;利用方法重复性限参数,计算可能产生的最大相对偏差。分析方法精密度满足《地质矿产实验室测试质量管理规范》的要求。  相似文献   

16.
铜镍硫化物矿床的成矿机理新探   总被引:7,自引:1,他引:6  
描述岩浆中铜、镍、钴、铁迁移富集新机制。铜、镍、钴、铁呈氢化物迁移至地壳浅部,氢被氧化成水,铜、镍、钴、铁被硫化成硫化物及硫砷化物富集成矿床。  相似文献   

17.
Organic materials dissolved in surface waters have long been implicated in metal binding and transport. In particular, fulvic and humic acids are considered to have a significant impact on speciation, total metal levels in solution and on the persistence of those metals. This work emphasizes the role played by dissolved organic matter (DOM) on the complexation of nickel, copper and cobalt and on its application to interpretation of surface water hydrogeochemical survey data. Waters from a number of well-known mining districts in Canada have been studied; in particular from Cobalt (Ontario), Sackville (New Brunswick) and Thetford Mines (Quebec). The diafiltration binding technique was used and shows that nickel, copper and cobalt are complexed significantly by DOM in natural waters. The tendency towards complexation was found to be Cu > Ni > Co. The binding functions determined were observed to be highly sensitive to pH and ligand:metal ratios; a gradation of binding site strength is evident.Data from some hydrogeochemical surveys conducted in the Kenora, Algoma and Ottawa districts of Ontario have been reinterpreted in the light of available data on the complexation behaviour of nickel, copper and cobalt. Occurrence of large water-borne anomalies unsupported by lake sediment loadings is most likely for cobalt and nickel and least likely for copper according to both field observations and experimental data. These studies provide good evidence for the formation of strong solution stable metal-organic species; the principal differences in persistence and migration behaviour are probably due to rates of coagulation and adsorption-precipitation processes which preferentially remove copper from solution. It is fair to conclude that these metals can be of use in mineral exploxation surveys using surface waters provided caution is exercised in interpretation of anomalies, especially in the absence of supporting sediment anomalies. Dissolved organic matter concentrations should always be determined when nickel, copper and cobalt are to be employed.  相似文献   

18.
The V-Ni-Co variation trend of Roberts Victor eclogites is toward the enrichment of vanadium at the expense of nickel with relatively little change of cobalt. The systematic V-Ni-Co variation together with petrographic evidences suggest that Group I and Group II eclogites from Roberts Victor Mine were most probably formed by fractional crystallization.  相似文献   

19.
湖南宝山矿床处于坪宝矿带的北端,是湘南地区最大的铜多金属矿床。为了进一步探讨矿区内花岗质岩石的形成条件及成矿潜力,文章在详细的野外地质和岩相学观察的基础上,对与成矿密切相关的花岗闪长斑岩中的黑云母进行了详细的矿物化学分析。电子探针分析结果表明:宝山花岗闪长斑岩中的黑云母为铁质黑云母和镁质黑云母,其中,Ti介于0.18~0.30,且Mg/(Mg+Fe2+)值介于0.42~0.58,属于典型的岩浆成因黑云母;黑云母的氧化系数为0.16~0.26,w(Mg O)为8.17%~11.72%,平均9.3%,MF值范围为0.38~0.50,指示其岩体属于壳幔混源型的I型花岗岩;岩体中以黑云母的全铝含量计算的结晶压力为97~174 MPa,相应的结晶深度为3.67~6.57 km,平均深度为5.12 km。其log f(O2)变化范围为-14.5~-12.8,表明黑云母是在较高氧逸度条件下结晶形成的,有利于铜矿的形成。  相似文献   

20.
The Jingbaoshan platinum-palladium deposit is China's largest independent PGM (platinum-group metals) deposit so far discovered. There are eleven kinds of useful components in the ore: Pt, Pd, Os, Ir, Ru, Rh, Au, Ag, Cu, Ni, and Co. The platinum-group elements, gold and silver occur in the form of minerals in ores. twenty-five kinds of precious metal minerals have been found, of which twenty one belong to the platinum-group minerals. The minerals are very small in grain size. Copper occurs mainly as copper sulfide with a small amount of free copper oxide, and the beneficiated copper accounts for 95.21%. Nickel occurs mainly as nickel sulfide, and some nickel silicate and nickel oxide occur in the ore. The beneficiated nickel accounts for 72.03%. Cobalt occurs mainly as cobalt sulfide, and there are some cobalt oxide and other kinds of cobalt. The beneficiated cobalt accounts for 77.58%.  相似文献   

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