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1.
Fifty-two samples of Miocene pelitic sedimentary rock from outcrops on Medvednica,Moslavacka Gora and Psunj Mts.,and boreholes in the Sava Depression and the Pozega Sub-depression were investigated.These sediments formed in different marine(with normal and reduced salinity),brackish,and freshwater environments,depending on the development stage of the Pannonian Basin System.Carbonate minerals,clay minerals and quartz are the main constituents of all pelitic sedimentary rocks,except in those from Moslavacka Gora Mt in which carbonate minerals are not present.Feldspars,pyrite,opal-CT,and hematite are present as minor constituents in some rocks.Besides calcite,dependent on the sedimentary environment and diagenetic changes,high-magnesium calcite,aragonite,dolomite and ankerite/Cadolomite are also present.Smectite or illite-smectite is the main clay minerals in the samples.Minor constituents,present in almost all samples,are detrital illite and kaolinite.In some samples chlorite is also present in a low amount.Major elements,trace elements and rare earth elements patterns used in provenance analysis show that all analysed samples have a composition similar to the values of the upper continental crust(UCC).The contents of major and trace elements as well as SiO_2/Al_2O_3,K_2O/Al_2O_3,Na_2O/K_2O,Eu/Eu~*,La/Sc,Th/Sc,La/Co Th/Co,Th/Cr,Ce/Ce~* and LREE/HREE ratios,show that the analysed pelitic sedimentary rocks were formed by weathering of different types of mostly acidic(silicic),i.e.felsic rocks. 相似文献
2.
This paper (Part II) constitutes the second of a two part series todefine the seven elements of avalanche forecasting. Part I contains the first four elements which are neededto present the human issues. This paper contains the last three elements which deal mostly with thephysical issues and their use in the decision-making process. Some basic rules of applied avalancheforecasting are included here, for the first time, to illustrate physically based principleswhich are used in applied avalanche forecasting and their link to data analysis and decisions.Since the seven elements of applied avalanche forecasting are strongly connected, the reader should consultPart I (this journal issue) as a prelude to the present paper. Part II contains sections about dataand information, scale issues in time and space, decision making and errors and physical rules ofapplied forecasting. Since all seven elements of applied avalanche forecasting are connected, Part II does not stand alone. 相似文献
3.
We present detailed experimental results on the partitioning of rare earth elements (REE) between titanite and a range of different silicate melts. Our results show that Henry’s law of trace element partitioning depends on bulk composition, the available partners for heterovalent substitution, crystal composition, and melt composition. We illustrate that the partition coefficients for Sm depend very strongly on the bulk concentration of Sm in the system. The substitution mechanism, by which rare earth elements are incorporated into the crystal structure, plays an important role for trace element partitioning and also for the onset of Henry’s law. Our data show that there are clear differences between substitution mechanisms of major elements compared to elements which are present only as traces. Our experiments also clearly show that the onset of Henry’s law depends on the concentrations of the sum of all trace elements which are incorporated into the crystal by the same substitution mechanism. For geochemical modelling of magmatic processes involving titanite, and indeed other accessory phases, it is of crucial importance to first evaluate whether the REE, and other trace elements, are present as traces or as major elements, only then appropriate D values may be chosen. 相似文献
4.
U.M. Cowgill 《Geochimica et cosmochimica acta》1973,37(10):2329-2345
Aquatic plants, water, lake mud, soils and rocks from Linsley Pond were analyzed for all the naturally occurring elements of the periodic table which could be detected by optical and X-ray emission spectroscopy. In the course of this study, it was noted that all the rare earths of even atomic number were detected; of the odd-numbered members of the group only La and Pr were found. The others were presumably present in amounts below detection. These elements relative to their concentration in the soils and rocks of the basin are absorbed by plants, giving an enrichment of about one hundred fold relative to Al on a dry weight basis. Samarium is present in excess of Nd in the rooted emergent plants but not in the submerged rooted or rootless ones. There is some suggestion of a fractionation of the rare earths in different parts of the plants. A comparison of the relative accumulation of trace elements with their content in the sediment suggests that Y, La, Ce, Pr, Sm, Dy, Er and Yb may be essential trace elements. 相似文献
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6.
Kuppusami GOVINDARAJU 《Geostandards and Geoanalytical Research》1982,6(1):91-159
All data reported by 200 analysts (106 laboratories) are presented for the four ANRT samples: Diorite DR-N, Serpentine UB-N, Bauxite BX-N and Disthène DT-N. Recommended values are given for the major and minor elements. As far as the as trace elements are concerned, DR-N has been characterized for 35 elements whereas the other three samples have been for only 20 elements. Wherever possible, brief comments have been inserted so as to explain our way of assigning recommended or proposed values.
After more than a decade of existence the total number of data reported for all the four samples reach only 3200 units which are not sufficient enough for a valid evaluation of compiled data. It is also pointed out that these samples are most likely to be available even during the next century as they have been prepared in large quantities of the order of one ton. A plea is therefore made for contribution of more data particularly for trace elements and for major elements which are present as trace elements in UB-N, BX-N and DT-N. 相似文献
After more than a decade of existence the total number of data reported for all the four samples reach only 3200 units which are not sufficient enough for a valid evaluation of compiled data. It is also pointed out that these samples are most likely to be available even during the next century as they have been prepared in large quantities of the order of one ton. A plea is therefore made for contribution of more data particularly for trace elements and for major elements which are present as trace elements in UB-N, BX-N and DT-N. 相似文献
7.
要认识地球的演化和全球变化,就必须有一致性的全球尺度地球化学基准或基线作为参照标尺。文中阐述了地球化学基准概念、建立方法和应用实例。地球化学基准是指系统记录元素及其化合物在地球表层的含量和空间分布,作为了解过去地球化学演化和预测未来地球化学变化的定量参照标尺。要建立全球地球化学基准,首先必须建立一个覆盖全球的地球化学基准网,在中国以1∶20万图幅为基准网格单元,在全国系统采集有代表性岩石组合样品约10 000件,疏松沉积物样品约6 000件,精确分析涵盖元素周期表上除惰性气体以外几乎所有元素的含量,制作化学元素时空分布基准地球化学图,提供衡量中国大陆化学元素演化和未来变化的标尺。以不同时代岩石代表性样品建立原生岩石圈地球化学基准,作为了解过去地球化学演化参照标尺,如云南禄丰龙产地楚雄—兰坪盆地白垩系-古近系界面(K-T界面)的凝灰质灰岩和凝灰质泥岩中发现Ir的含量为0.25～0.8ng/g,是白垩系和古近系地层基准含量的10～20倍。以疏松沉积物样品建立次生土壤圈地球化学基准,用于作为预测未来变化的参照标尺,如CaO含量分布与气候和酸雨分布有关,CaO在南方酸雨作用下淋失贫化,在西北碱性条件下富集。在过去15年里,由于酸雨的持续作用,CaO平均含量下降了22.6%,CaO含量<1%的分布面积扩大了23.0%。同时,这种原生和次生地球化学基准的建立,提供了具有时间和空间分布的成矿物质背景,对矿产资源评价和预测具有重要意义。 相似文献
8.
Kristine Krogh Jensen Joel Baker Tod Waight Robert Frei David W. Peate 《Geostandards and Geoanalytical Research》2003,27(1):59-66
We present high precision Ir, Ru, Pt, Pd, Re and rare earth element (REE) determinations by isotope dilution multiple collector-ICP-MS on the Cretaceous-Tertiary boundary sedimentary reference material FC-1. Samples for platinum-group element measurements were digested in Carius tubes followed by acid digestion. The platinum-group elements were subsequently separated by anion exchange chemistry and determined by multiple collector-ICP-MS. The accuracy of the platinum-group element analyses have been verified by comparative analyses of the reference materials WITS-1 and GP13 (sample size 0.5-1 g). Replicate analyses of FC-1 (sample size 0.2 g) exhibit good reproducibility (RSD < 5%) for all the analysed platinum-group elements. REE data also exhibit excellent reproducibility (RSD < 0.5%), which indicates that this sample is homogeneous for the determination of the platinum-group elements and REE at the 0.2 g level. 相似文献
9.
C. Frick 《Journal of Geochemical Exploration》1985,24(1):51-80
A study of the soil profiles in the central Transvaal showed that in most areas a thick top layer of transported soils is present. Since this transported horizon has moved for considerable distances and because mixing took place in the process, the use of soil geochemistry in the search for hidden ore bodies tends to yield erratic results. In the present investigation an attempt was made to use volatile elements such as Hg, As, S and C as CO2 as geochemical indicator elements and to establish whether epigenetic haloes of these elements are imprinted on the transported soils. The geochemical behaviour of these elements are compared with elements such as Ni, Co, Cu and Fe, which would tend to migrate with the transported soil.The geochemical study was done on the Platreef in the Bushveld Complex, north of Potgietersrus. The Platreef consists of a stratified horizon which contains appreciable amounts of chalcopyrite, pyrrhotite, pentlandite and platinum-group elements. Four traverses across the ore body were investigated and the results indicate that in cases where the soil cover is relatively thin, approximately 1 to 2 metres, all the elements studied can be used to locate the ore body. Those traverses where the soil cover is thicker and where transported soils are definitely present, only mercury yields significant anomalies, while siderophile elements give erratic and poor results. The mercury anomalies are usually not displaced and even tend to delineate mineralized sub-zones of the Platreef.Arsenic, sulphur and carbon measured as total CO2, also give erratic results in the cases where a thick soil cover is present. The fact that arsenic tends to be fixed relatively easily in soils, either in laterite particles or in surface limestone, apparently is the prime reason for its erratic behaviour. The results indicate that both S and C would yield unsatisfactory results if these elements are measured as total S and C in the soils. The use of gas species may be more successful.A surprising but consistent result, was the tendency for mercury to be concentrated in the soils above faults, which intersect the ore body at depth. The behaviour of mercury in soils taken along the strike of a fault indicated that a logarithmic relationship exists between the mercury concentration in the soil and the depth of the ore body. 相似文献
10.
通过分析德合龙洼铜金矿床区域地质、矿床地质特征,利用钻孔岩心样品分析微量元素分布规律,运用1∶5 000原生晕确定多元素组合异常规律,对矿区进行成矿预测。研究表明,钻孔ZK01-1的前晕元素、中晕元素和尾晕元素均指示出该孔-210m处的强矿化区段,说明其微量元素的分布对成矿作用具有较好的指示意义;从原生晕地球化学特征可知,在矿体的东北部、西北部极有可能存在隐伏矿体,在矿区的东北角和西南部也有可能存在隐伏矿体;因子分析中成矿元素在主因子F3和F1均有较高的因子载荷,说明本区的成矿作用是多阶段多成因的。通过综合研究确定3个找矿预测靶区,为矿山进一步开展找矿工作提供了重要依据。 相似文献
11.
浙江安吉铅锌多金属矿区细粒花岗岩的岩石化学、年代学及成矿意义探讨 总被引：2，自引：0，他引：2
文章在详细的野外地质调查、岩石学、岩石化学和锆石U-Pb定年结果基础上,对浙江安吉矿区细粒花岗岩的岩浆起源、侵位时代与成矿的关系及找矿指示意义等进行了较为深入的探讨.细粒花岗岩侵位时代日于矿区的黑云母二长花岗岩、正长花岗岩和花岗闪长岩,侵位时代约在134 Ma左右,为中国东部东侏罗世一早白垩世岩石圈活化及大规模成岩成矿作用的产物.岩石化学研究结果表明,细粒花岗岩属高钾钙碱性钾玄岩、过铝质岩石系列,轻稀士元素相对富集,重稀土元素相对亏损,富集大离子亲石元素Rb、Th、U、K、轻稀土元素和Pb,明显亏损高场强元素Nb、Ta、Ti和P,显示较高的分异程度.据根锆饱和温度,计算其母岩浆结晶温度约在834.6 ～ 870.6℃.结合矿区已知的矿化和蚀变与细粒花岗岩的空间关系、细粒花岗岩岩石化学特征以及细粒花岗岩与矿石铅同位素研究结果,笔者认为,安吉铅锌多金属矿区铅锌钼矿化与细粒花岗岩具有密切的成因联系,细粒花岗岩与寒武系灰岩接触部位控制了矽卡岩型铅锌矿化的产出,这一成果对该区的进一步找矿勘查具有重要的指导意义. 相似文献
12.
A review of chlorine and bromine in some United Kingdom coals 总被引：1，自引：0，他引：1
D.A. Spears 《International Journal of Coal Geology》2005,64(3-4):257-265
In the UK there is a longstanding interest in the Cl content of coals because of the adverse effects associated with high-Cl coals during combustion. An average Cl content of a representative suite of coal samples is 0.44 wt.%, but the range is from near zero to over 1%. Several lines of evidence show that in the high-Cl coals the Cl is associated with the coal moisture and that other sources, such as the silicate minerals, are negligible. Although the Cl is moisture associated there is anion exchange with the organic matter, which means that Cl is less than 100% water- soluble unless the Cl is exchanged with other anion species. This occurs if carbonates are present and calcite in particular. The Cl and Br are closely related and the location within the coal is thought to be common to both. These two elements differ from nearly all other trace elements in UK coals in that they are not present in significant concentrations in the mineral matter or bound within the organic matter. Whereas there is a good understanding of the geochemical behaviour of these other elements this is not the case for Cl and Br in the coal moisture. Chlorine and Br are thought to be conservative elements in the diagenetic evolution of the porewaters, in which an original marine depositional imprint could have been preserved. In some areas the porewaters may have fully evolved pre-Permian, whereas in other areas the diagenetic evolution could be much longer. 相似文献
13.
Trace element fractionation and transport in boreal rivers and soil porewaters of permafrost-dominated basaltic terrain in Central Siberia 总被引：1，自引：0，他引：1
The chemical status of ∼40 major and trace elements (TE) and organic carbon (OC) in pristine boreal rivers draining the basaltic plateau of Central Siberia (Putorana) and interstitial solutions of permafrost soils was investigated. Water samples were filtered in the field through progressively decreasing pore size (5 μm → 0.22 μm → 0.025 μm → 10 kDa → 1 kDa) using cascade frontal filtration technique. Most rivers and soil porewaters exhibit 2-5 times higher than the world average concentration of dissolved (i.e., <0.22 μm) iron (0.03-0.4 mg/L), aluminum (0.03-0.4 mg/L), OC (10-20 mg/L) and various trace elements that are usually considered as immobile in weathering processes (Ti, Zr, Ga, Y, REEs). Ultrafiltration revealed strong relationships between concentration of TE and that of colloidal Fe and Al. According to their partition during filtration and association with colloids, two groups of elements can be distinguished: (i) those weakly dependent on ultrafiltration and that are likely to be present as truly dissolved inorganic species (Li, Na, K, Si, Mn, Mo, Rb, Cs, As, Sb) or, partially (20-30%) associated with small size Fe- and Al-colloids (Ca, Mg, Sr, Ba) and to small (<1-10 kDa) organic complexes (Co, Ni, Cu, Zn), and (ii) elements strongly associated with colloidal iron and aluminum in all ultrafiltrates largely present in 1-100 kDa fraction (Ga, Y, REEs, Pb, V, Cr, Ti, Ge, Zr, Th, U). TE concentrations and partition coefficients did not show any detectable variations between different colloidal fractions for soil porewaters, suprapermafrost flow and surface streams. TE concentration measurements in river suspended particles demonstrated significant contribution (i.e., ?30%) of conventionally dissolved (<0.22 μm) forms for usually “immobile” elements such as divalent transition metals, Cd, Pb, V, Sn, Y, REEs, Zr, Hf, Th. The Al-normalized accumulation coefficients of TE in vegetation litter compared to basalts achieve 10-100 for B, Mn, Zn, As, Sr, Sn, Sb, and the larch litter degradation is able to provide the major contribution to the annual dissolved flux of most trace elements. It is hypothesized that the decomposition of plant litter in the topsoil horizon leads to Fe(III)-, Al-organic colloids formation and serves as an important source of elements in downward percolating fluids. 相似文献
14.
浙江安吉坞山关杂岩体岩相学和岩石地球化学特征及岩石成因 总被引：1，自引：0，他引：1
位于钦—杭成矿带东段北缘的浙江安吉多金属矿区发育侵位序列复杂的坞山关杂岩体及与其有关的蚀变和矿化.为了探讨区内岩浆岩与成矿的关系,在野外调查的基础上,文章对该杂岩体的岩相学、岩石地球化学开展了研究,并籍此对其成因类型、源区特征进行了探讨.坞山关杂岩体由黑云母二长花岗岩、花岗闪长岩和正长花岗岩组成,前者具富碱、高钾特征,属准铝质-钾玄岩系列,花岗闪长岩具高钾特征,属准铝质-高钾钙碱性系列,正长花岗岩具高硅、低钙、贫镁、高FeO/MgO值、富碱特征,属准铝-弱过铝质钾玄岩系列.该杂岩体的∑REE为(123.5～216.47)×10-6,稀土元素配分型式呈明显的右倾轻稀土元素富集型,Eu呈不同程度的负异常.微量元素蛛网图中,各岩石单元大离子亲石元素(尤其是Rb、Th、K)明显富集,Ba、Sr负异常明显,相对亏损高场强元素Nb、Ti、P.该杂岩体成矿元素ω(Mo)、ω(W)明显高于克拉克值,暗示其具有提供成矿物质的潜力.黑云母二长花岗岩为分异Ⅰ型花岗岩,花岗闪长岩属Ⅰ型花岗岩,正长花岗岩具有A型花岗岩的多数特征,但从杂岩体各岩石单元的成岩年龄相差不大、具地球化学亲缘性以及A型花岗岩不具高分异特征来考虑,将其归为高分异Ⅰ型花岗岩更理.La/Sm-La图解显示出,该杂岩体为平衡部分熔融作用所形成,其轻稀土元素富集、Ta-Nb、Ti、Eu、Sr、Ba负异常可能是源区为含角闪石族、金红石、斜长石作为难熔相遗留在残留物中所致. 相似文献
15.
D.A. Spears A.G. Borrego A. Cox R.M. Martinez-Tarazona 《International Journal of Coal Geology》2007,72(3-4):165-176
Laser ablation ICP-MS has been used to produce element profiles from polished coal samples. The elements analysed (V, Ge, Ni, Cu, Zn, Sr and Ba) were those known to have an organic association, with the addition of Al and Fe as controls on the clay and pyrite abundances. The element profiles were compared with the petrography and a statistical analysis was also carried out. Sporinite was found to have low trace element concentrations, inertinite higher concentrations of detrital elements and vitrinite higher concentrations of V, Ge and Al. The relationships between these elements are explored and all are thought to be present in the organic matter and not as minerals. It is thought that these elements became concentrated during diagenesis, with the possibility that some of the Al could be residual. The Cu/Ni ratio in the pyrite is relatively constant, suggesting constant ionic proportions during diagenesis, and possibly a seawater source. 相似文献
16.
Acta Geotechnica - Helical soil nails are passive elements installed in the soil which attains its bond strength through skin friction and bearing from helices. The present study examines the... 相似文献
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18.
蒙古国东南部巨斑状二长花岗岩地球化学特征与岩石成因机制探讨 总被引：1，自引：0，他引：1
巨斑状二长花岗岩是蒙古洋板块早古生代晚期重要的岩浆记录,其花岗岩年龄和地球化学特征对于揭示蒙古洋板块该时期的构造格局与演化历史有重要意义。对蒙古国东南部出露的巨斑状二长花岗岩进行锆石的LA-ICP-MS法定年,获得锆石U-Pb年龄为(454.3±3.8) Ma,表明该二长花岗岩形成于晚奥陶世。花岗岩的元素地球化学研究结果表明：该花岗岩属高钾钙碱性I型花岗岩;花岗岩具高硅特征,其SiO2质量分数为69.82%~75.16%,A12O3质量分数为12.91%~14.49%,Na2O/K2O为0.60~0.77,过铝质,其铝饱和指数为1.11~1.22,Mg#指数为39~44;稀土元素总量为(43.47~158.11)×10-6,稀土元素分布型式为具有明显负铕异常的“燕型”曲线（δEu=0.26～0.49）;在原始地幔标准化的微量元素蛛网图中,Rb、Th、U、K、Zr、Hf和轻稀土元素(如La、Ce、Nd和Sm等)富集,Ba、Sr、P和Ti等元素强烈亏损,Nb和Ta具有中等-弱亏损特点;143Nd/144Nd初始比值较高(0.512 449~0.512 507),平均为0.512 477;εNd(t)为0.2~1.3,均为正值。主量、微量元素和同位素特征表明,该巨斑花岗岩形成于同碰撞向后造山构造体制转换过渡的伸展大地构造环境背景之下。伸展构造和幔源基性岩浆的底侵,很可能是形成花岗岩的2个最主要的动力机制。 相似文献
19.
Pia VOLDET 《Geostandards and Geoanalytical Research》1983,7(2):281-282
The rare-earth elements (REE) content of the FER-1, -2, -3, -4 canadian reference samples has been determined by neutron activation and high-resolution X-ray or γ-ray spectrometry. As these rocks are included in a new project of standardisation, the present results have not been compared with other data. 相似文献
20.
Trace-element determinations of 15 coal samples have been made in order to know their distribution, behaviour and associations with the organic and inorganic fractions in the coal. The coal samples have been systematically collected in stratigraphic sequences so that the vertical variation of the trace-elements can be studied. The elements determined by spectographic analysis are W, V, Cr, Sc, Y, Cu, Co, Pb, Be, Ni and Ba. The results indicate that the concentration of trace elements in these coals varies greatly from bottom to top sections. The elements V and Co are extremely poor in the top and middle sections, whereas in the bottom section they are fairly distributed. Be is extremely poor in the bottom section, and fairly distributed in the middle and top sections. W, Sc, Y have poor concentration in the bottom section as compared to the middle and top sections. Ni is fairly distributed in the bottom section whereas its concentration is poor in the middle and top sections. Cr and Cu are fairly distributed in the bottom, middle and top sections. Ba has unusually high concentration in all the sections.It appears from the present study that W, Cr, Sc, Y and Be are concentrated more in silicate minerals (clay, quartz, etc.) associated with coal, and the elements like , Co, and Ni have intimate relation with organic matters in coal and are present as organometallic compounds as well as absorbed cations. Cu and Pb which are present in the coals are derived from the inorganic matter, mainly from the pyrites, whereas W has affinity with carbonate minerals in the coals. The Ba is mainly associated with the inoraanic matter of coal; its unusually high concentration indicates association with carbonates, clays and other silicate minerals. 相似文献