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1.
Granite GS-N and Potash Feldspar FK-N are two ANRT reference samples prepared in 1973 in 960 and 567 kg, respectively. All data reported since 1973 are compiled in this report. GS-N and FK-N are now well characterized for major and minor elements. As for trace elements, working values have been assigned for 36 elements in GS-N and for 30 elements in FK-N. We need much more data on trace elements for characterizing them better. As GS-N and FK-N are still available in large quantities and are certain to remain so for two or three decades to come, a plea is made for contribution of more data on trace elements.  相似文献   

2.
南京及周边地区土壤地球化学特征及基础地质应用探讨   总被引:2,自引:0,他引:2  
吴新民  金洋  翁志华 《江苏地质》2007,31(3):180-186
南京及周边地区区域多目标地球化学调查与评价对调查区表、深层土壤采样分析了54项指标。提供了南京地区54项指标的表、深层土壤背景值,对比分析了背景值特点,讨论了元素地球化学区域分布特征,探讨了基础地质研究中地球化学在地层岩性、岩相划分方面的应用。  相似文献   

3.
剪切带损伤研究对于理解材料破坏机制和建立剪切带本构模型具有重要意义。为了研究单轴压缩黏性土样的剪切带损伤演化规律,根据纵向应变较高时清晰剪切带位置布置切向测线,对数字图像相关方法获得的结果进行双三次样条插值,从而获得光滑性较好的各种应变场。将土样整体的损伤变量-纵向应变曲线与各条剪切带的损伤演化曲线进行了对比。研究发现:(1)总体上,土样整体的损伤变量演化曲线呈线性,而各条剪切带的损伤变量演化曲线均上凹,这表明随着纵向应变的增加,各条剪切带的损伤发展越来越快;(2)各条剪切带的损伤变量演化曲线的轮廓线呈马尾形,这说明随着剪切带的逐渐发育,各条剪切带的相互影响和作用规律变强;(3)对于含水率较低的土样,平行或共线剪切带的损伤变量变化基本同步,特别是在剪切带充分发育之后,但两条剪切带的距离应较小;在一定时期,共轭或交叉剪切带中剪切带的损伤占优,这与剪切带的相互竞争有关,但若两条剪切带达到独立发展的程度,则二者的损伤变量变化可以同步;对于含水率较高的土样,各条平行或共轭剪切带的损伤变量变化基本同步,剪切带的相互作用不明显。  相似文献   

4.
Turkey lies on the Alpine-Himalayan belt which is one of the most important geothermal belts in the World. Therefore, there are numerous mineral waters in Anatolia where geological and tectonic activities are intense. Archeological studies conducted in Anatolia, which is the cradle of various civilizations, reveal the fact that mineral water has been used as a spa in many areas.The scope of this study is to evaluate mineral waters in Western Anatolia and their use in thermal resorts for balneological purposes. In this respect, 50 thermal waters used in spa centers were analyzed for various physical, chemical and bacteriological parameters.Among the 50 waters tested, 40 are thermomineral waters while 10 are acratothermal waters. Some of these waters have distinct chemical compositions. Their temperatures are between 21 and 90 °C. Various types of mineral water source occur within this region: 5 of these are sulfurous, 1 has carbon dioxide, 29 have fluorine, 1 has iodine and 3 are saliferous. The thermomineral sources with saline characteristics have balneotherapy potential for treating skin illnesses including psoriasis and rheumatological illnesses.Some waters with appreciable bicarbonate and sulfate concentrations can also be used for balneotherapy; for example for use as a cure for chronic inflammatory diseases of gastrointestinal and urinary systems. They could also be used as a cure for prophylactic and metaphylactic treatment of urolithiasis.However, among 38 sampling sites, 12 sites are bacteriologically contaminated. This indicates that regulations governing the protection of such zones are not properly enforced and that water sources within these regions are not sufficiently protected or inspected.  相似文献   

5.
Global data are presented for sources of atmospheric input for 20 trace metals, and the relative importance of natural and anthropogenic sources is assessed. Interference factors are calculated as (total anthropogenic emissions/total natural emissions) × 100. For lithophile metals such as Fe and Mn, interference factors are small. In contrast, the atmophile metals, such as As, Se and Hg, exhibit large interference factors. A significant degree of correlation exists between interference factors and enrichment factors, where enrichment factor is defined as the metal/Al ratio in atmospheric particulates divided by the metal/Al ratio in soils. For many of the trace metals, enrichment factors are of the same order of magnitude at high latitudes in both the Northern and Southern Hemispheres, and are larger at high latitude than at mid latitude.A simple mathematical model is used to calculate present-day enrichment factors in both hemispheres based on natural and anthropogenic influxes, effluxes, and transfer between hemispheres. The calculated enrichment factors are in good agreement with the observed enrichment factors for lithophile metals at both mid and high latitude, and for atmophile metals at mid latitude. However, calculated enrichment factors for atmophile metals are lower than observed enrichment factors at high latitude. To explain these results, we propose that for Hg, As and Se, and perhaps for other atmophile metals, there are significant fluxes from the sea surface to the atmosphere. If the estimated low-temperature fluxes of As, Se and Hg from the land and sea surfaces are included in the interference factor calculations for these metals, the factors are reduced to less than 100%.  相似文献   

6.
Canonical variate analysis is extended for use when the covariance matrices are not equal. Linear combinations of variates are derived by generalizing either a weighted between-groups approach or the likelihood-ratio test and the associated noncentrality matrix. The usual solution and the two generalizations are compared via generated data for a few typical configurations of means in a situation in which the covariance matrices are in fact equal. The MSE of the canonical variate coefficients and group means for the generalizations are approximately three times those for the usual solution, due to corresponding changes in the variances. Two examples are discussed.  相似文献   

7.
Al X-ray absorption K-edge spectra were calculated for atom clusters which simulate Al surrounded by oxygens in tetrahedral and octahedral environments in five minerals, and are compared with experimental Al K-edge spectra from the same minerals. The experimental data show simple edges, for Al tetrahedra, that are shifted to lower energy by 2 eV compared with more complicated edges for Al octahedra. The calculated edge itself is due to a strong 1s to 3p resonance in the μ0 for Al. The shifting of the calculated edges is due to different molecular potentials used and different types of atomic scattering. The calculated edge features for tetrahedral Al are all similar, and are due primarily to single scattering from the tetrahedral oxygens. Calculated edge features for octahedral Al are more complicated and are dominated by multiple scattering. The calculated edge features resemble the experimental data, but are much larger in amplitude than their experimental counterparts.  相似文献   

8.
电子自旋共振(ESR)技术是一种确定物质成分和结构的顺磁性质的分析方法,也能够用于沉积物定年。该方法的测量技术和测年的物理机制等还处于发展阶段。冰川作用过程十分复杂,形成各种类型的冰川沉积物,其顺磁信号的归零机制有显著差异,ESR测年的实验方案也有所差异。因此,识别冰碛物类型,采集合适的样品对于ESR测年的准确性十分重要。冰下融出碛和滞碛经过了冰下磨蚀过程,结构致密,细颗粒基质含量高,石英砂中的一些杂质芯的ESR信号能够衰退。许多冰上融出碛,结构疏松,但细颗粒基质含量高,不但经过了搬运过程中的冰下磨蚀过程使ESR信号衰退,又经历了沉积时的冰上阳光直射过程使信号衰退,一些样品的ESR信号能够完全晒退。冰水湖泊和冰水河流沉积的细砂和粉砂来源于冰下研磨的产物,信号会衰退;在搬运沉积过程中又可能被阳光直射,信号进一步衰退。其它类型的冰碛物的ESR信号衰退机制不明,或粒径不适合用ESR方法测年。采集冰碛物ESR年代样品时,最好同时采集信号衰退机制相同的现代冰碛物样品,以便对照,并用于扣除可能的残留信号。  相似文献   

9.
陕西子长油田成藏地质特征   总被引:2,自引:0,他引:2  
从烃源岩、储集层、圈闭、油气运移及富集条件等方面入手,对子长油田成藏地质特征进行了研究。认为子长油田延长组油气生成及油气初次运移条件均较好,但储层、油气二次运移及富集条件相对较差。延长组主要有五种油藏类型,油气分布主要受储层物性、岩性、岩相等条件所控制。  相似文献   

10.
刘建达  高俊锁  董卫国 《岩土力学》2007,28(Z1):769-772
与岩土工程相关的设计地震动参数的规定分散在各行业的工程设计规范之中,比较了主要技术规范中设计地震动参数规定之间的差别,讨论了在岩土工程的勘察与设计中确定地震动参数的方法和内容,分析和研究了确定设计地震动参数时不同规范之间需要协调的主要问题,指出了在目前岩土工程中的设计地震动参数确定方面的需要重点关注的参数选择的合理性,提出了具有地震工程专业基础(注册地震安评工程师)的注册土木工程师(岩土)确定具体设计地震动参数应更符合工程建设的实际需要的建议。  相似文献   

11.
In this paper, numerical methods for flow simulation in the well vicinity are discussed. Flux truncation errors are analyzed on gridblocks near the well. Due to the singularity of the well, standard numerical schemes are not efficient for near well flow simulations. To improve simulation accuracy, a new methodology, using a change of coordinates to make near well pressure linear, is presented for the singularity modelling. Based on this new approach, two numerical schemes, a two-point flux approximation scheme and a multi-point one, are proposed. These schemes are accurate for the near well modelling and are suitable for any kinds of gridblocks.  相似文献   

12.
The requirement for quantitative thermal property data in assessing the performance of an engineered repository is identified. Experimental methods for the measurement of thermal conductivity, thermal expansivity and heat capacity are outlined and typical test results are presented for two rock-types of interest in relation to the Sellafield site. The controls on the thermal properties are discussed and a series of corrections from the rock material to the rock mass properties are presented. Finally, a correction scheme that accounts for the effect of scale is followed.  相似文献   

13.
凉山州境内的富铁矿按成因可分为火山型、热液型、沉积变质型、沉积型等类型,本文逐一对其分布、地质特征及规模等方面进行了叙述和总结;对主要富铁矿产地和储量作了统计,并介绍了主要矿区开发现状及经济效益。提出了今后矿山开发、资源保扩及寻找富铁矿的建议。  相似文献   

14.
高铝粉煤灰中部分主微量元素的分布规律研究   总被引:3,自引:2,他引:3  
本文旨在研究部分主微量元素在高铝粉煤灰中的分布规律,从而为其资源化利用提供科学依据。首先根据高铝粉煤灰的物相组成特点采用新的分离方法将之分离为三个相(或相组合):铁质微珠、莫来石-刚玉相以及玻璃相;然后分别用化学分析和ICP-MS测试主微量元素在高铝粉煤灰、铁质微珠以及莫来石-刚玉相中的含量,并结合相关数据计算出这些元素在玻璃相中的含量。结果表明,除Al、Mn外,其他元素均在玻璃相中有不同程度的富集;除Al外,其他元素则在莫来石-刚玉相中有不同程度的贫化;除Ti以外的铁族元素以及除Ga、Pb以外的金属成矿元素均在铁质微珠中富集,其他元素则在其中贫化。  相似文献   

15.
Construction material resources of Lebanon are discussed in terms of geology, distribution and production. This is a first attempt with a systematic approach. Crushed rocks form the bulk of total production, and are used for cement, concrete and pavement. They are all produced from limestones ranging in age from Jurassic to Tertiary. Sands, other than those coming from crushed rocks, are produced from Quaternary deposits, or from the basal Cretaceous sandstone formation (Gres de Base). They are used for cement, concrete, pavement and glass. Dimension and face stones are also produced from the limestones. The mosaic and pottery industry uses clays which are mostly in seams or pockets within the basal Cretaceous unit. This study points out to the need for a systematic compilation of pertinent data to facilitate evaluation of supplies for future development.  相似文献   

16.
Geochemistry and origin of elements in some UK coals   总被引:3,自引:0,他引:3  
Twenty-four UK coals ranging in rank with 4.6%–37.6% volatile matter were analysed for 46 major and trace elements. The samples were obtained from the UK Coal Bank and are representative of the major UK coal fields. The major element distributions are interpreted in terms of the mineralogical variations—quartz and kaolinite are largely responsible for the Si and Al, carbonates for Ca and Mg and pyrite for Fe. Also exerting an influence in some samples are siderite, Al-phosphate minerals and illite. Based on statistical relationships with the major elements, Rb, Cr, Th, Ce, Zr, Y, Ga, La, Ta, Nb and V are thought to be mainly present in the clay minerals, and As, Mo, Sb, Tl, Se and Bi and Pb are probably present in pyrite. Strontium and Ba are concentrated in a restricted number of samples related to the phosphate minerals. Germanium is the only element for which a major organic association can be demonstrated. Elements with an indirect association with the organic matter are Na, Cl, and Br in porefluids and possibly Te. The ash content is controlled mainly by the detrital input and the trace elements related to the ash content are therefore those elements associated with the clay minerals. Variations with rank would appear to be mainly related to the moisture content (porefluids). The trace elements associated with the quartz and clay minerals are thought to be dominantly detrital in origin. The non-detrital elements, essentially those contained in pyrite, are thought to have been incorporated in the depositional environment from waters with enhanced salinities through seawater ingress, hence there are positive relationships between S and trace element concentrations.  相似文献   

17.
《International Geology Review》2012,54(12):1820-1828
Supergenesis, sedimentational lithogenesis, and technological activities of man are characterized here in brief, as well as the geocosmochemical processes. Principal types of geochemical territories are indicated for supergenesis and sedimentational lithogenesis. Considerations are presented for expansion of the research in supergenesis and lithogenesis, and its fundamental orientations and major problems are defined. -- Authors  相似文献   

18.
A new model for unsaturated flow in porous media, including capillary hysteresis and dynamic capillary effects, is analyzed. Existence and uniqueness of solutions are established and qualitative and quantitative properties of (particular) solutions are analyzed. Some results of numerical computations are given. The model under consideration incorporates simple ‘play’-type hysteresis and a dynamic term (time-derivative with respect to water content) in the capillary relation. Given an initial water content distribution, the model determines which parts of the flow domain are in drainage and which parts are in imbibition. The governing equations can be recast into an elliptic problem for fluid pressure and an evolution equation for water content. Standard methods are used to obtain numerical results. A comparison is given between J.R. Philip's semi-explicit similarity solution for horizontal redistribution in an infinite one-dimensional domain and solutions of the new model.  相似文献   

19.
Earthquake-induced landslides in Central America   总被引:11,自引:0,他引:11  
Central America is a region of high seismic activity and the impact of destructive earthquakes is often aggravated by the triggering of landslides. Data are presented for earthquake-triggered landslides in the region and their characteristics are compared with global relationships between the area of landsliding and earthquake magnitude. We find that the areas affected by landslides are similar to other parts of the world but in certain parts of Central America, the numbers of slides are disproportionate for the size of the earthquakes. We also find that there are important differences between the characteristics of landslides in different parts of the Central American isthmus, soil falls and slides in steep slopes in volcanic soils predominate in Guatemala and El Salvador, whereas extensive translational slides in lateritic soils on large slopes are the principal hazard in Costa Rica and Panama. Methods for assessing landslide hazards, considering both rainfall and earthquakes as triggering mechanisms, developed in Costa Rica appear not to be suitable for direct application in the northern countries of the isthmus, for which modified approaches are required.  相似文献   

20.
Models for thermodynamic behavior of FeO-bearing liquids are required for understanding the separate roles of evaporation, condensation and crystallization in the formation of free-floating silicate liquid droplets in the early solar nebula. These droplets, frozen as chondrules, are common in chondritic meteorites. Evaporation coefficients for Fe and FeO of ∼0.2 are calculated here from existing data using silicate liquid activity models. These models, used to describe gas-liquid-solid equilibria and to constrain kinetic processes, are compared and found similar, and the effects of liquid non-ideality are assessed. A general approach is presented for predicting the evaporation behavior of FeO-bearing Al2O3-CaO-SiO2-MgO liquids in H2-rich gas above 1400 K at low total pressure. Results are vapor pressure curves for Fe, FeO and other gas species above typical chondrule liquids, suitable for predicting compositional trajectories of residual liquids evaporating in a hydrogen-dominated vapor. These predictions are consistent with chondrule formation in the protoplanetary disk in heating events of short duration, such as those expected from shock wave or current sheet models.  相似文献   

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