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1.
This study highlights the response of the periodic variation of the geochemical behavior of elements to the thermal metamorphism of coal by considering the differentiation mode and differentiation degree of elements of the C2 coal seam in the Fengfeng mining area of the Handan Coalfield in Hebei, China. The periodic variation of the geochemical behavior of elements was observed to change towards a certain direction as the degree of metamorphism of a geological body increased. Based on the coincidence degree (or similarity degree) between the geochemical behavior of elements and periodic variation of elements, the 57 elements in this study were divided into two levels. The periodic variation of the geochemical behavior of first-level elements was largely synchronous with that of their first ionization energy, suggesting that only one differentiation mode exists and the elements are mainly inorganically associated. The differentiation mode of the second-level elements deviated to a certain extent from their first ionization energy; the larger the deviation, the more complicated and diverse was the differentiation mode. Among the second-level elements, the grade of coal metamorphism has evident and intuitive effects on the proportion of elements with particular structural features, such as the 4q+3 type of elements and the odd-odd elements. In addition, the distribution of elements in organic and inorganic matter within coal are subject to the structural features of the elements. The differentiation mode and differentiation intensity of elements could be characterized by the hierarchical parameter and differentiation intensity. The hierarchical parameter and differentiation intensity of certain elements showed a good positive or negative correlation with Rmax in coal. The 57 elements in this study were quantitatively ordered according to the degree of magmatic hydrothermal fluid influence and thermal metamorphism of coal through graphs depicting the goodness of fit, correlation coefficient with Rmax, and differentiation intensity. The results of this study are consistent with the results of previous field research, illustrating the scientific significance and application value of this study on the periodic variation of the geochemical behavior of elements.  相似文献   

2.
吴榕榕 《地质与勘探》2020,56(5):955-968
以梵净山西麓印江县紫薇镇古茶树立地剖面上的岩石和土壤为研究对象,使用ICP-MS和ICP-AES测定21种元素的含量,分析古茶树立地岩石-土壤系统的地球化学特征,以期为印江县古茶树保护及开发提供科学依据。结果表明:古茶树生长地岩石-土壤系统的主量、微量和重金属元素富集程度低(EF <3),受人为因素影响程度小,可为古茶树提供安全的生长环境。其中主量元素K和Al在岩石-土壤系统中含量丰富,Ca、Mg、Na元素含量较少,符合茶树喜钾嫌钙的生理特征;微量元素在岩石-土壤系统中含量变化均匀,但与地球化学丰度值和中国土壤背景值相比,其含量较少;重金属元素含量均低于无公害农产品种植业产地环境条件限定值。同时研究发现该岩土系统中Se元素含量丰富,可为当地发展富硒茶提供参考。  相似文献   

3.
The first data on trace-element geochemistry, REEs included, of the Devonian clastic and volcanosedimentary complexes in the Magnitogorsk Megazone have been obtained with ICP-MS. The correlation links and the character of distribution indicate that many elements, including those readily passing into solutions during weathering, were transferred as mechanical suspensions. Therefore, minerals concentrating these elements were largely preserved, as also were the distribution and concentrations of elements inherent to the source rocks. Both accessory minerals (apatite, zircon, Ti-minerals, and magnetite) and rock-forming minerals (pyroxene, amphibole, biotite, serpentine, chlorite, and plagioclase) were found among mineral concentrators. Clay minerals also seem to have participated in the processes. The typical elements of various complexes were identified. The distribution of trace elements is correlated with the stratigraphic position of rocks and depends on the character of the petrographic provinces.  相似文献   

4.
为研究准格尔串草圪旦5号煤微量元素地球化学特征,采用光学显微镜、扫面电子显微镜和X射线衍射(XRD)方法观测煤中矿物组成及形态特征,应用电感耦合等离子质谱(ICP MS)方法测定煤中多种微量元素含量,运用数理统计方法研究微量元素在煤中的赋存特征。结果表明:5号煤中Li、Be、F、U、Hg 5种元素相对富集,含量高于研究区6号煤及中国煤中含量水平。5号煤中Li、F、Ga、Se无机亲和性强,Be、As、U为亲有机元素;Hg与硫含量显著正相关。各元素在煤中主要以有机结合态、无机结合态和硫化物结合态赋存。  相似文献   

5.
李冰  何红蓼等 《地质通报》2003,22(2):130-134
简要介绍了痕量超痕量分析新技术新方法在地质调查中的开发应用研究进展,内容包括地质调查项目背景和重要性,锍镍试金-ICPMS测定贵金属元素分析方法,高压密封酸溶-ICPMS在测定地质样品中痕量超痕量稀土、稀有稀有散、铌钽锆铪等47种元素的应用,卤素等非金属元素分析方法等研究进展及成果。  相似文献   

6.
Sediment samples at 10 locations in the mainstem of the Yellow River were taken in 1994. Five forms (exchangeable, carbonate, organic, Fe/Mn oxide and residual) of metals were extracted by the Tessier method. The total contents and contents of the five forms of 16 metal elements (Li, Na, K, Ca, Sr, Ba, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, and Al) were determined by ICP-AES. In sediments of the Yellow River, except for Na, mobile elements (such as K, Ca) do not show a negative correlation with the immobile elements. Alkaline metals (Li, Na, and K), Ti, and Al exist mainly in the residual form. The exchangeable forms of alkaline-earth elements (Ca, Sr, and Ba) are the highest, and their residual forms go up with the increase of the period in the periodic table of elements. Half of Mn exists in the residual form, and its non-residual forms exist mainly in carbonate and oxide forms. Except Mn, the iron group elements (Fe, Co, Ni, V, Cr) mainly exist in the residual and oxide forms. High carbonate content of Ca does not cause high contents of other elements in carbonate form, showing that chemical weathering is not strong in the area.  相似文献   

7.
泾河下游古洪水滞流沉积物地球化学特征研究   总被引:1,自引:0,他引:1  
通过沿泾河河谷广泛的野外考察,在高陵县杨官寨段发现典型的全新世黄土-土壤剖面。经过详细观测、系统采样和化学元素、粒度成分和磁化率等多指标测定,从剖面鉴别出两组古洪水滞流沉积层(SWD),分别记录了发生在4 200 ~ 4 000 a B.P.和3200 ~ 2800 a B.P.期间的特大洪水事件。该研究着重对古洪水滞流沉积层与黄土层和古土壤层的元素地球化学特征进行对比研究。结果表明:(1)在风成沉积物中,Fe2O3、Al2O3、K2O、MgO等元素含量在古土壤层高于黄土层,而CaO和Na2O元素含量则表现出相反的变化。表明风化成壤过程中,这些元素的迁移变化受到全新世以来气候变化和成壤作用的影响。而Zr、Hf、Ti、Cr、Y、Th等微量元素含量与地壳平均丰度相当,且变化甚微。这是由于这些微量元素主要包含在粗颗粒和重矿物之中,其化学性质比较稳定,具有强抗风化性,很少受到风化成壤作用的影响。(2)单个古洪水滞流沉积层,是洪水悬移质泥沙在高水位滞流环境中沉积形成的,分选性很好,故其底部多粗颗粒和重矿物沉积,Zr、Hf、Ti、Cr、Y、Th等微量元素含量呈现突出的尖峰;自下向上随着颗粒逐渐变细,粘粒成分增加,Fe2O3、Al2O3、K2O、MgO等元素含量出现高峰。这两类元素由下向上的相互消长关系,与沙级颗粒含量和磁化率值变化规律对应,反映出古洪水滞流沉积层的基本理化特性。这个研究成果对于完善古洪水沉积学和水文学的方法和理论具有重要的科学价值。  相似文献   

8.
华北板块北缘东段早前寒武纪稀土元素演化特征   总被引:1,自引:0,他引:1  
通过对区内早太古宙深变质地体、晚太古宙花岗岩-绿岩地体,晚太古-早元古宙优地槽和火山岛弧各类变质岩稀土元素的研究,三个时期的稀土元素具大致相似的演化特征,不同时期相同的岩石类型的稀土配分型式也大致相似,反映了它们有着相同源岩。但是,它们又在稀土丰度、Eu异常和轻、重稀土分离程度方面表现出某些差异,表明本区在早前寒武纪的不同时期、不同构造环境中地壳成分的不均一性。不同岩石类型稀土配分的多样性,说明岩浆源不同,至少有超镁铁质、镁铁质和安山质或英云闪长岩-奥长花岗岩三种岩浆源。  相似文献   

9.
衡阳盆地北缘国庆矿区土壤地球化学特征及找矿方向   总被引:1,自引:0,他引:1  
杨笑笑 《地质与勘探》2018,54(4):762-771
对国庆矿区开展了1∶10000地质简测,在了解矿区地质特征的基础上进行了1∶10000土壤地球化学测量工作。Cu、Pb、Zn、Au、Ag、W、Mo7种微量元素含量特征(变异系数、富集系数和浓集比率)显示,Cu、Au、W元素为区内成矿有利元素。运用统计学软件SPSS19对7种微量元素含量值进行R型聚类分析和R型因子分析,划分出Cu-Pb-Ag和Au-Mo两组主成矿元素组合。采用衬度异常法对成矿有利元素和两组主成矿元素组合进行处理成图,共圈定了2个异常靶区。经过地表工程和深部工程验证,确定了一条一定规模的工业铜矿体。  相似文献   

10.
以淮北煤田二叠纪10、7、3煤层样品为研究对象,采用仪器中子活化法(INNA)测试了煤中42个伴生元素的含量,将其与华北石炭-二叠纪和中国煤中的伴生元素含量、范围进行了对比,并对伴生元素中主量元素含量和灰分的关系、微量元素的共生组合特点以及稀土元素含量与灰分的关系、稀土元素分布模式进行了初步分析。结果表明,对环境有影响的Ba、Co、Cr、Cu、Mo、Th、V、W、Zn、Ti元素在研究区煤中相对富集,Al、Ti、K、Na等元素与灰分有较好的相关性,Ca、Mg、Fe和灰分的相关性较差,稀土元素与灰分正相关且具有相似的分配模式,普遍存在Eu亏损现象,说明煤中伴生元素的主要来源是陆源物质。  相似文献   

11.
过实验室模拟海带的早期成岩作用过程,获得生物改造无定形体样品,观察海带形态变化,测定生化成分、碳氢 氮元素及微量重金属元素含量,为海相底栖宏观藻类的烃源岩形成过程提供现代对比实例。研究结果显示海带在模拟过程 中不断降解,到第 67 天海带细胞已经完全破碎呈无定形体状;微生物促进海带生化成分的转化,厌氧后期多糖和蛋白质含 量下降,粗脂肪含量上升到 8.16%;海带对微量重金属元素有显著的吸附解析作用,使微量元素含量波动变化。早期成岩 过程中微生物改造使海带形态朝无定体转化;有利于脂类成分的增加,利于成烃;元素变化有一定规律,但要直接利用微 量重金属元素进行油源对比可能还存在一些问题,需要进一步研究。  相似文献   

12.
黑潮化学物质输入东海的途径与通量   总被引:3,自引:0,他引:3  
在对黑潮水文特征分析的基础上,探讨了黑潮对中国近海化学物质输入途径,归纳总结了黑潮对东海生源要素、痕量元素、同位素及其他化学物质的输入特征,提出了黑潮对中国近海化学物质输入研究应着重关注的问题。主要的结论包括:吕宋海峡、中国台湾东北部及日本九州西南海域是黑潮向中国近海输送化学物质的3个关键区域;黑潮表层水向东海陆架的扩展、次表层水和中层水的涌升以及黑潮季节性流轴摆动是黑潮向东海输送化学物质的基本途径。黑潮主体生源要素的浓度随深度的增加而增大。黑潮对东海生源要素的影响夏季最弱、春季次之、秋冬季最强,其对东海生源要素的输入通量要远高于河流、大气等其他输入源,并且各水层中以中层水的生源要素输入通量为最大。痕量元素在黑潮主体的分布、对东海的输入通量等方面均表现出了与生源要素的差异,各痕量元素的分布及输入通量随痕量元素的不同而不尽相同,其中次表层水的涌升在对邻近海域痕量元素分布的影响中起到了重要作用。同位素可指示黑潮对东海陆架的入侵程度及变化规律,并与营养盐等有一定的相关性。黑潮是东海微量温室气体N2O,CH4等其他化学物质的重要输入源,进而对东海生态环境产生影响。进一步研究应着重从系统性外海观测、痕量元素及同位素等化学物质调查、黑潮对中国近海输入化学物质的控制过程等方面深入开展。  相似文献   

13.
The mineral composition, distribution and fractionation of rare-earth elements in dissolved and suspended forms (solid residue) of atmospheric precipitation were studied by analyzing the snow sampled over urbanized territory by the example of the city of Blagoveschensk. Electron-microscopic studies revealed the own minerals of rare-earth elements in dust aerosols. It is shown that the main sources of the atmospheric pollution by rare-earth elements were emissions of TPP (heat and power plants) and boiler houses. Contrasting geochemical anomalies of rare-earth elements were found in the snow cover of the city. The REE concentrations in the solid phase of snow are few orders of magnitude higher than those of the liquid phase. The snow solid phase provides insight into the REE behavior, because it directly reflects the impact of different anthropogenic sources. The characteristic feature of the REE distribution in the solid residue of snow is their LREE enrichment relative to MREE and HREE. The average HREE content is 10% of total REE. In the snow water–solid phase system, most samples show weak fractionation between LREE and HREE owing to the low total mineralization of the snow liquid phase and the small content of organic matter.  相似文献   

14.
Soils and selected edible plants of the Noun river catchment basin of western Cameroon were sampled to investigate the distribution of trace elements, based on the preliminary idea of unusual anomalies. Analytical techniques for trace elements included ICP-AES, GF-AAS, and ICP-MS. Further soil analyses comprised the mineralogy and contents of the biogenic elements carbon, nitrogen and sulphur (CNS). The trace element concentrations in the soils reflect those of the lithogeochemical background of the pluto-volcanic rocks of the region. This is consistent with the results from the mineralogical analyses and physicochemical parameters such as pH, taken in the field, which also do not suggest any geochemical anomaly. Most trace elements analyzed in the plants showed concentrations that reflect those of the soils (Al, Fe, Ti, and Rb). However, some trace elements were enriched in the plants as compared to the soils, such as Zn, Cu, Cd, Mo (excluding yam), Ni (peanut), Ba (peanut), Sr (peanut, bean), and B. Trace elements such as As, Cr, V, and Se were not bioavailable for all the analyzed plants. Besides, trace elements such as Cu, Zn, Mo, Fe, Al, Ni, B, Ti, Rb, Cs, and Ba were in the range of phytotoxicity and reached or exceeded human food tolerance level (Cu). The plants with seeds showed a higher absorption of trace elements compared to plants with tubercles.  相似文献   

15.
为研究火山岩地区土壤中营养元素的浓度水平及其空间分布特征,选取黑龙江五大连池卧虎山农场为研究区,系统采集41件表层土壤样品,测试分析氮、磷、钾等植物营养元素以及有机质、pH值等15项指标,绘制元素地球化学图,掌握了该区营养元素含量的空间分布特征。根据相关标准,评价土壤中营养元素的丰缺水平。结果表明:(1)研究区为酸性土壤,土壤营养元素含量总体丰足,只有硼含量稍缺或缺乏;(2)土壤营养元素具有明显的空间分布规律,以卧虎山北部含量较高、跃进水库附近较低为特征;(3)研究区为温暖湿润条件下的中等化学风化,伴随着成土作用营养元素持续从岩石释放到土壤中,且有机质对土壤营养元素具有良好的吸附性。本研究为当地农业生产中养分的合理利用和农业种植规划提供了第一手数据资料。  相似文献   

16.
在内蒙草原覆盖区迪彦钦阿木Mo-Ag矿床长度为106.5 m黄土覆盖层垂直岩心上等间距顺序取样106个,用Niton XL3t X-荧光仪测得每个样本的33个元素的含量.在正态性检验的基础上,用Kendallτ相关系数分析了元素含量与深度的相关性,得出黄土覆盖层中Mo、S、W、Te、Fe、Cu、Ni、Mn、Sb、Rb、Cs、Sn、Zn、Ti、V、Pb、Th、As这18种元素含量与离开矿源的距离具有显著相关性;用HP滤波法分离出这18种元素含量空间序列的长期趋势,并用变量聚类分析法对长期趋势进行了分类;用因子分析法得到了迪彦钦阿木矿床Mo-W成矿因子和Pb-Zn成矿因子,并模拟得到Mo-W成矿因子的指数分布模式.本文的研究思路与结论可为覆盖区表层地球化学异常对矿产预测的指示作用研究提供借鉴.   相似文献   

17.
Potentially harmful element contamination from mining and smelting raises concerns due to possible health risks. For most people, diet is the main route of exposure to potentially harmful elements, so determination of the concentrations of these elements in foodstuffs and assessment of their possible risk for humans via dietary intake is very important. This study was designed to investigate the concentrations of different elements, including Hg, Pb, Cd, Mn and Se in foodstuffs and to estimate the potential health risk of these elements via consumption of polluted foodstuffs in the Wanshan Hg mine area, Guizhou province, SW China. The multielemental concentrations were determined by inductively coupled plasma-mass spectrometry (ICP-MS). The target hazard quotient (THQ) and hazard index (HI) were calculated to evaluate the potential health risk from individual and combined potentially harmful elements due to dietary intake. The average contents of Hg, Pb, Cd, Mn and Se in the most frequently consumed foodstuffs were: 31, 248, 121, 1035 and 32 μg/kg respectively. Among them, Cd and Hg were the most important contributors to potentially harmful elements contamination in Wanshan. Eight of 10 kinds of vegetables were contaminated to various levels by different elements but the samples of rice, pork, radish and potato were below the stipulated limits for toxic elements. In this study, the average dietary intakes of Hg, Pb, Cd, Mn, Se by an adult man of 60 kg living in Wanshan were: 27, 167, 86, 1061, 42 μg/day, respectively. The HIs for multielement dietary intake was 3.11, with the relative contributions of Hg, Pb, Cd, Mn and Se being 22.3%, 24.3%, 45.0%, 3.9% and 4.4%, respectively, which indicated that consumption of food poses a potential health risk. Vegetables were found to be the main source of potentially harmful element dietary intake.  相似文献   

18.
福建龙海杨梅产地元素地球化学特征   总被引:1,自引:0,他引:1       下载免费PDF全文
福建省是中国杨梅重要产地,其中龙海市浮宫杨梅因其独特品质而名扬海外,是当地的名特优农产品。以龙海杨梅产地为研究区,系统采集了35套岩石-土壤-杨梅果实样品,测定了主量组分、植物营养有益元素、有害元素以及土壤部分营养元素有效态含量。研究表明:受地质背景影响,浮宫镇及其周边杨梅产地土壤中植物营养有益元素的有效度及其有效量普遍高于东泗镇,而有害元素含量较低,为浮宫杨梅的优质高产、富硒杨梅产出提供了地质地球化学条件;土壤中植物营养元素P、Mn、Cu、Zn、S有效态含量与其全量显著正相关;研究区岩石、土壤Se含量均远高于全国平均水平,采集的35件杨梅果实样品富硒率高达74.3%;植物营养有益元素的富集系数明显高于有害元素,显示出杨梅对营养有益元素的选择性吸收以及对有害元素的阻遏作用。  相似文献   

19.
通过对新5钻孔晚新生代地层中的主要氧化物、微量元素和主要元素比值的变化特点进行研究分析。表明该地区自新近纪以来该地区气候总体趋势是由温暖湿润向温和干旱气候方向发展。其中经历了3个较大的氧化阶段。本文综合分析磁化率、古地磁和孢粉等资料。分析了主要氧化物、微量元素在不同地层中的分布特征。从地球化学角度把新5钻孔的沉积环境分为6个变化波动区间。揭示该地区晚新生代以来的气候经历了温暖湿润-温和湿润—温和偏干—温暖湿润—温凉湿润—温和偏干的气候波动。  相似文献   

20.
Trace-element analyses of seventy six coal samples representing all the major Lower Gondwana coal basins of India were carried out. Eighteen trace elements, viz., B, Ba, Co, Cr, Cu, Ga, Ge, La, Mn, Mo, Nb, Ni, Pb, Sn, Sr, V, Y and Zr were determined quantitatively in coal ash. An attempt was made to correlate the coals of different coalfields on the basis of multivariate analysis. In addition, the organic/inorganic affinities between the trace elements were established by the coefficients of correlation between the trace elements and ash present. A synthesis of the data reveals that there is similarity in the concentration ranges of trace elements among the coal seams of different coalfields, but the possibility of environmental differences exists due to the statistically different multivariate means of the trace-element concentrations.It is inferred that Ge, Cr, Y and La occur in these coals as organo-metallic complexes and chelates. The elements Ni, Co, Ga, V and Cu show both organic and inorganic association, whereas Mn and Ba are exclusively incorporated in the inorganic fractions.  相似文献   

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