露采矿山台阶边坡结构面特性与破坏机制分析

基于四川峨胜露天矿山台阶边坡的结构面特征,结合离散单元软件3DEC对台阶边坡进行模拟,研究台阶边坡破坏机制。结果表明:(1)受区域地质构造影响,研究区域的优势结构面倾角较陡,且产状与构造迹线相关;(2)矿区台阶边坡变形破坏模式主要为平面滑动和楔形体破坏,发生倾倒破坏的可能性小;(3)边坡整体变形小,在结构面贯穿的位置有位移突变和增大的现象,临空面的楔形体出露后发生崩塌掉块,局部稳定性降低;(4)台阶边坡破坏机制为拉裂-滑移-崩塌,可分为三个阶段:弹性变形阶段,渐进变形阶段和变形破坏阶段。     

间歇型降雨对堆积层斜坡变形破坏的物理模拟研究

为研究间歇型降雨作用下缓倾堆积层斜坡的变形破坏特征,以樱桃沟滑坡为例,进行了降雨作用下斜坡变形破坏的物理模拟研究。试验结果表明：前期降雨作用下坡体变形特征表现为前缘滑移沉陷、中部滑移、后缘沉陷、坡体裂缝生成,且前缘裂缝扩张明显,后期降雨作用下坡脚区域首先发生滑塌,然后依次向后缘传递发生逐阶滑塌破坏;降雨入渗易在基岩面上储存,形成暂态地下水位、高孔隙水压力区域和坡向渗流场,基岩面附近土体饱水时间长,软化程度高,抗剪强度弱化显著,边坡易沿基覆界面土层发生滑坡;坡体滑动易发生在降雨间歇期,触发特征表现为雨后坡体暂态饱和区水分和坡表积水持续下渗,导致地下水位上升滞后于降雨,造成坡体内浮托力、渗透力和孔隙水压力增大,有效应力降低,诱发滑坡。     

大型堆积体边坡基-覆界面及坡面动态响应特性试验研究

地震动力作用下堆积体边坡的变形破坏受多种因素影响,为研究基-覆界面及坡面倾角对松散堆积体边坡的动力响应影响,通过室内物理模型试验,模拟了水平向振动荷载作用下包含不同倾角的基-覆界面和坡面的堆积体边坡的变形破坏过程。试验结果表明,堆积体边坡的破坏模式由基-覆界面及坡面倾角共同控制,当基-覆界面倾角在一定范围内(15°)时边坡只发生浅表部局部滑塌破坏,不会发生沿基-覆界面的整体下滑;随着基-覆界面倾角的增大,边坡破坏形式由局部滑塌逐渐转变为以整体下滑为主;坡面坡度控制着边坡局部滑塌的范围。     

贵州某填方边坡滑塌变形破坏监测与治理

以贵州岩溶区某机场高填方边坡滑塌破坏为工程实例,根据边坡的地质勘察资料及现场调查情况,阐述了该高填方边坡滑塌变形破坏特征.根据变形监测的数据,详细分析了滑塌体的空间运行状态、变形破坏过程及变形机制,即下伏地层发生过大沉降变形时,导致了上部土体发生滑塌变形破坏,其特点是以沉降变形为主,兼有明显水平滑移.并介绍了治理措施及治理后的效果.     

永吉高速公路黑潭坪边坡三维稳定性研究

通过对永吉高速公路黑潭坪边坡的野外调查,详细地了解了研究区工程地质条件,探讨了边坡变形破坏机理,结合室内试验和计算反演获取岩土体强度参数,在此基础上建立三维地质模型,运用FLAC3D数值分析软件采用强度折减法对不同工况下的坡体稳定性进行详细分析并提出治理建议。研究表明:(1)边坡变形破坏是内外因素综合作用的结果,岩土体性质不良是边坡变形破坏的内在因素,坡脚便道开挖和地表水下渗是边坡变形破坏的诱导因素;(2)强度折减法应用于边坡三位稳定性分析具有较好的适用性;(3)数值模拟显示采用削坡结合锚固的综合治理措施具有明显的效果。     

古王陵变形破坏机理及稳定性研究——以国家重点文物高句丽太王陵为例

本文在现场工程地质条件及变形破坏特征勘察的基础上,对高句丽太王陵的稳定性进行了研究,并用三维有限差分程序FLAC3D对陵体在自重和渗流场藕合作用下的应力和变形规律进行了研究。研究表明:(1)太王陵出现的条石内倾、条石拉开等变形是由其本身的结构特点及其在自重作用下形成的;(2)持力层承载力不足,地基失稳是引起该国家重点文物破坏的主要原因;(3)陵坡滑移是由于本身安全储备较低,在地基失稳和地震等的共同作用下引发的。     

开挖条件下含陡倾结构面顺层岩质边坡破坏模式与稳定性预测

顺层岩质边坡易发生失稳破坏,当边坡中发育有顺坡向陡倾结构面时,更不利于边坡稳定。以贵州某水电站大坝左岸含陡倾结构面顺层边坡为例,在综合分析地质条件及开挖扰动的基础上,结合离散元软件UDEC,分析了边坡的变形破坏模式和稳定性。研究结果表明,边坡可能发生的变形破坏模式主要有滑移、拉裂—滑移两种;自然状况下及开挖后,边坡都有沿断层f_9、卸荷裂隙L_1及岩层面发生滑移的趋势,且工程开挖导致边坡沿该结构面发生内部滑动;对边坡采用预应力锚索加固后,变形得到有效控制,位移数值计算值与实际监测值基本吻合。     

基于颗粒元模拟的含软弱夹层类土质边坡变形破坏过程分析

采用基于离散单元法的颗粒元程序,引用平行连接模型,通过数值试验,确定土体细观参数与宏观力学性质的关系,并据此建立含软弱夹层的类土质边坡模型。通过路堑开挖卸荷过程模拟,再现了大变形条件下坡体渐进性破坏的完整过程,并对裂隙的发展演化过程进行实时监测。模拟结果显示,含软弱夹层类土质边坡的破坏过程历经裂隙的形成、扩大、发展直至贯通,最终发生大规模滑移破坏;裂隙从滑坡体前缘和软弱层面开始,范围逐步扩大,呈现典型的类土质边坡的渐进性破坏形式;滑坡发生后,土体结构破坏严重,承载能力大幅下降。边坡滑移过程模拟和最终滑移结果与现场滑坡状况完全吻合,表明该方法适用于类土质边坡变形破坏过程分析及其机理研究。     

陕西省金堆城露天矿排土场高边坡稳定性评价

通过野外实地调研,在详细研究金堆城露天矿排土场高边坡地质条件和边坡变形破坏特征的基础上,分析了该边坡的变形破坏机制,将破坏方式归纳为两种类型:蠕滑-拉裂破坏,拉裂-滑移破坏。通过圆弧法和破坏概率法计算和分析了高边坡在天然、爆破振动和地震条件下5个不同剖面地段的稳定性状态,并利用FLAC数值模拟进行验证,最后,根据变形破坏方式提出了相应的处理措施。为高边坡的稳定性评价、预测和防治提供了有价值的参考。     

西南某机场高填方边坡滑塌机制分析与处理措施研究

西南某高填方机场土石方工程竣工后不久遭遇了持续半月的强降水,在一次突发暴雨后4h,边坡发生了滑塌。采用监测、检测、现场调查、原位试验、室内试验、数值模拟等手段进行综合分析。结果认为,该机场高填方边坡滑塌主要是采用含碎石黏性土填筑的土面区、边坡影响区,因强夯补强破坏了填筑体内原有的碎石排水层,造成了采用碎石填筑的道槽区入渗的降水不能及时排出而引发的高地下水压力、渗透变形、浸泡软化等共同作用所致。最后针对性地采取填筑体顶面薄膜覆盖,坡面出水点网装级配碎石反滤和引流、滑塌坡面袋装碎石回填的应急处理措施,以及填筑体顶面黏性土回填、坡面碎石换填、仰斜管排水的永久处理方法,有效地控制了边坡的进一步变形、滑塌,取得了良好的灾害治理效果。     

Taxonomical and Biogeochemical Investigation of Elements in Holocene Mollusk Shells in the South and Southwestern Marmara Basin, Turkey

Concentrations of some heavy metals and trace elements such as Cr,Ga,Ni,Zn,Mo,Cu, Pb,Yb,Y,Nb,Ti,Sr,Ba,Mn,Sc,Co,V,Zr,Fe,Al,W,Se,Bi,Sb,As,Cd in recent mollusk shells and factors affecting their distribution and deposits collected from various depths in the southern and southwestern parts of the Marmara Sea are investigated.The distribution of the elements in the shells is categorized into four groups.Of these,concentrations of 12 elements(As,Bi,Cd,Co,Ga,Mo,Nb, Sb,Se,Sc,W and Yb)are below zero [(0.053-0.79)×10~(-6)];concentrations of seven elements(Cr,Ni, Pb,V,Y,Zr and Cu)are(1.0-6.0)×10~(-6);concentrations of four elements(Ti,Mn,Ba and Zn)are 10- 20×10~(-6);and concentrations of five elements(Si,Al,Fe,Mg and Sr)are(47.44-268.11)×10~(-6).The taxonomic characteristics of the 29 elements were studied separately in mollusk shells such as Chamalea gallina(Linné),Pitar-rudis(Poll),Nassarius reticulatus(Linné),Venerupis senescens (Coocconi),Mytilus galloprovincialis(Lamarck),Mytilaster lineatus(Gemelin in Linné)and Chlamys glabra.It was found that,in mollusk taxonomy,the elements have unique values.In other words, element concentrations in various mollusk shells depend mainly on the taxonomic characteristics of mollusks.In various bionomic environments different element distributions of the same species are attributed to the different geochemical characters of the each environment.Data obtained in this study indicate that the organisms are the most active and deterministic factors of the environment.     

中国煤中的九种金属元素

在煤的加工利用过程中,煤中金属元素进入大气、水体和土壤,以致污染环境,这是人们关心的事。本文将介绍镉、钴、铬、铜、锰、钼、镍、铅、锌等九种元素在我国煤中的分布和赋存情况。     

Selenium and heavy metals content in some Mediterranean soils

The study of metal contents in industrial, agricultural or/and polluted soils compared with natural or unpolluted soils is currently necessary to obtain reference values and to assess soil contamination. Nonetheless, very few works published appear in international journals on elements like Se, Li and Sr in Spanish soils. This study determines the total levels of Se, Li, Sr, As, Cd, Co, Cr, Cu, Ni, Pb, V, Zn, Fe, Mn and Ba in 14 natural (unpolluted) soils (Gypsisols, Leptosols, Arenosols and Acrisols), 14 agricultural soils (Anthrosols, Fluvisols and Luvisols), and 4 industrial–urban affected-surface soil horizons (Anthrosols and Fluvisols) of Eastern Spain. The geochemical baseline concentrations (GBC) and reference values (RV) have been established, and the relationships among elements and also between soil properties and elemental concentrations have been analysed. The RV obtained in this study were (mg kg⁻¹): Se 2.68, Li 115, Sr 298, Cd 0.97, Co 35, Cr 217, Cu 46, Ni 50, Pb 137, V 120, Zn 246, Fe 124,472, Mn 2691, and Ba 743. The RV for Se and Li were used as a preliminary approach to assess soil contamination in Spanish soils. The results confirm human impact on Sr, As, Cd, Cr, Cu, Ni, Pb and Zn soil concentrations, but evidence no deviation from natural Se, Li, Co, V, Fe, Mn and Ba concentrations. The results obtained from the statistical analysis reveal significant correlations between some elements and clay and soil organic matter (SOM) contents, indicating that metal concentrations are controlled by soil composition. One particularly interesting finding is the high correlation coefficients obtained between SOM and Se, Cd, Cr, V, Fe, and Mn, and between clay and Cd, Zn, V, Fe and Mn. Once again, these facts confirm the role of SOM and clay minerals in soil functions and that soil is an ecosystem element responsible for maintaining environmental quality.     

Synthesis and Preliminary Characterisation of New Silicate, Phosphate and Titanite Reference Glasses

Eleven synthetic silicate and phosphate glasses were prepared to serve as reference materials for in situ microanalysis of clinopyroxenes, apatite and titanite, and other phosphate and titanite phases. Analytical results using different micro-analytical techniques showed that the glass fragments were homogeneous in major and trace elements down to the micrometre scale. Trace element determinations using inductively coupled plasma-mass spectrometry (ICP-MS), multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS), laser-ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) and secondary ionisation mass spectrometry (SIMS) showed good agreement for most elements (Li, Be, B, Cs, Rb, Ba, Sr, Ga, Pb, U, Th, Y, La, Ce, Pr, Nd, Sm, Eu, Gd, Er, Tm, Yb, Lu, Zr, Hf, Ta, Nb) studied and provide provisional recommended values.     

Geochemical and mineralogical properties of sulfide-bearing fine-grained sediments in Finland

 The geochemical and mineralogical characteristics of bulk samples and various size fractions of sulfide-bearing fine-grained sediments in the Petalax area, western Finland, were studied with ICP-AES (aqua regia digestion and "total" digestion) and X-ray diffraction. The sediments, which are dominated by particles <0.06 mm (clay and silt size), are composed of phyllosilicates (micas, kaolinite, chlorite, vermiculite), quartz, feldspars, amphiboles, organic matter, and secondary S minerals. The chemical analyses show that Na, Ca, and Sr are enriched in the silt and sand fractions, that Zr is enriched in the silt fraction, and that the concentrations of all other studied metals (Al, Ba, Co, Cr, Cu, Fe, K, La, Mg, Mn, Nb, Ni, Sc, Th, Ti, V, Y, and Zn) increase from the sand to the clay fraction. Sodium, Ca, and Sr occur largely in poorly dissolved feldspars, which explains the distribution of these metals in the sediments. The increase in the concentrations of most metals in the clay fraction is interpreted to be the result mainly of an increase in phyllosilicates in this size fraction. A geochemical comparison between the sulfide-bearing fine-grained sediments and glacial till shows that the former are enriched in several potentially toxic metals. It is therefore argued that the hydrological and ecological problems associated with the sulfide-bearing sediments are related not only to the production of acidity in oxidized layers, but also to mobilization and dispersion of toxic metals. Strategies to minimize damage of freshwater systems in areas covered with sulfide-bearing fine-grained sediments are suggested. Received: 20 February 1997 · Accepted: 25 August 1997     

Geological characteristics of the Sizhuang gold deposit in the region of Jiaodong, Shandong Province——A study on tectono-geochemical ore prospecting of ore deposits

Tectono-geochemical samples were systematically collected from 5 drillcores along the No. 304 explora-tion line and at the -310 m level under the pit in the mining area, totalling 705 samples from the metamorphic rocks, granites, altered rocks and orebodies, and were determined for their contents of 20 kinds of elements including Au, Ag, As, Sb, Hg, Cu,,Pb, Zn, Sn, Bi, Mo, Co, Ni, Mn, Cr, V, Ti, Ba, Rb, Sr, etc. By using the Surfer software the geochemical exploration line profile maps for the 20 kinds of elements and the curves for the element geochemical contents of individual ore vein groups were established. In conbination with the geochemical map analytical method and Gregorian’s zoning index calculation method, the vertical, longitudinal and lateral zonation sequences of the elements were ascertained and the geochemical three-dimentional zonation model of the primary halos was estab-lished on the basis of the analysis of metallogenic structures and alteration zonation. Coupled with the results of analysis of the geology and geochemistry data, it may be concluded that the process of alteration of granites in the mining area is also accompanied with the process of gold enrichment and mineralization. With the intensification of alteration of granites from granite →potash feldspathization granite →sericite-quartz alteration granite, seric-ite-quartz rocks →beresitized granite, pyrite sericite-quartz rock, silicified granite →gold ore, the contents of thio-phile ore-forming elements such as Au, Ag, As, Cu, Bi, Mo, Pb, Sb, Hg, and Sn tended to increase. Factor analysis of trace elements indicated: factor F2 (Au, Ag, Cu, Sn, As) represents the element association brought in at the main stage of hydrothermal metallogenesis; factor F4 (Bi, Sb) and factor F5 (Pb, Zn) represent the ore-forming element association supperposed during the late stage of Au-bearing sulfides. By using the Gregorian’s zoning index and map analysis method we have ascertained the primary halo axial zonation sequence (form frontal halo →tail halo): Pb, Zn, Mn, Ba, Sr, Rb, As, Sb, Ag, Cu, Sn, Mo, Au, Bi, Hg, Ti, Cr, V, Ni, and Co. The geochemical anomalies in the mining area display a tendency of lateral plunging to WS, which is consistent with the lateral plunging of orebodies and mineralization alteration zone. Comprehensive analysis of the results of investigations on ore-controlling structures, mineralization-alteration zonation and geochemical zonation of the primary halos indicates that the gold orebodies in this area are still of greater extension.     

Abundances and modes of occurrence of trace elements in the Çan coals (Miocene), Çanakkale-Turkey

This study presents the concentrations and modes of occurrence of trace elements in 81 coal samples from the Çan basin of northwestern Turkey. The concentration of trace elements in coal were determined by inductively coupled plasma-mass spectrometry and inductively coupled plasma-atomic emission spectrometry. Additionally, traditional coal parameters were studied by proximate, ultimate, X-ray diffraction, and petrographic analyses. Twenty trace elements, including As, B, Ba, Be, Cd, Cu, Co, F, Hg, Mo, Ni, Pb, Sb, Se Sn, Th, Tl, U, V, and Zn, receive much attention due to their related environmental and human health concerns. The Çan coals investigated in this study are lignite to sub-bituminous coal, with a broad range of ash yields and sulphur contents. The trace element concentrations show variety within the coal seams in the basin, and the affinities vary among locations. The concentrations of B, Ba, Be, Cd, Cu, Co, F, Hg, Mo, Ni, Pb, Sb, Se, Sn, Tl, and Zn in Çan coals are within the Swaine's worldwide concentration range, with the exception of As, Th, U, and V. On the other hand, compared with world coals, the Çan basin coals have higher contents of As, B, Cu, Co, Mo, Pb, Th, U, V, and Zn. Based on statistical analyses, most of the trace elements, except for U, show an affinity to ash yield. Elements including As, Cd, Hg, Se, Cu, Mo, Ni, and Zn, show a possible association with pyrite; however, the elements Se, B, and Mo can be have both organic and inorganic associations.     

内潮汐沉积研究及其存在的问题

内潮汐沉积是深水沉积研究中的一个非常年轻的研究领域,自1990年发现首例内潮汐沉积以来,沉积学工作者做了 大量不懈的努力,不仅发现了一系列内潮汐沉积实例,而且还对已发现的内潮汐沉积的特征、垂向序列和沉积模式进行了 总结,同时还认为内潮汐沉积可能成为油气潜在的良好储层。但是到目前为止,发现的内潮汐沉积的研究实例十分有限, 因此,内潮汐沉积研究中还存在一系列的尚待解决的问题。首先是内潮汐沉积的鉴别标志和识别方法尚不完善;其次是目 前尚缺少现代内潮汐沉积的典型实例研究,难以全面认识内潮汐对沉积作用的影响;第三是沉积学研究尚未将海洋物理学 的相关研究成果应用在内潮汐沉积的研究中,也未开展相关的内潮汐沉积实验模拟研究,更未利用地层记录中内潮汐沉积 特征反演内潮汐的物理特征,从而制约了内潮汐沉积的形成过程、形成机理、形成条件和形成环境的研究;第四是对内潮 汐沉积的研究意义认识不足。在下一步的研究中,应结合海洋物理学的相关研究成果对现代内潮汐沉积进行观察和研究, 同时开展相关的内潮汐沉积的实验模拟研究,并对古代内潮汐沉积进行反演研究。此外,还应将理论研究与油气等资源研 究相结合,从而更好地促进内潮汐沉积研究的发展。     

Taxonomical and Biogeochemical Investigation of Elements in Holocene Mollusk Shells in the South and Southwestern Marmara Basin,Turkey

Concentrations of some heavy metals and trace elements such as Cr, Ga, Ni, Zn, Mo, Cu, Pb, Yb, Y, Nb, Ti, Sr, Ba, Mn, Sc, Co, V, Zr, Fe, Al, W, Se, Bi, Sb, As, Cd in recent mollusk shells and factors affecting their distribution and deposits collected from various depths in the southern and southwestern parts of the Marmara Sea are investigated. The distribution of the elements in the shells is categorized into four groups. Of these, concentrations of 12 elements （As, Bi, Cd, Co, Ga, Mo, Nb, Sb, Se, Sc, W and Yb） are below zero [（0.053-0.79）×10^-6]; concentrations of seven elements （Cr, Ni, Pb, V, Y, Zr and Cu） are （1.0-6.0）×10^-6; concentrations of four elements （Ti, Mn, Ba and Zn） are 10- 20×10^-6; and concentrations of five elements （Si, Al, Fe, Mg and Sr） are （47.44-268.11）×10^-6. The taxonomic characteristics of the 29 elements were studied separately in mollusk shells such as Chamalea gallina （Linn6）, Pitar rudis （Poli）, Nassarius reticulatus （Linn6）, Venerupis senescens （Coocconi）, Mytilus galloprovincialis （Lamarck）, Mytilaster lineatus （Gemelin in Linne） and Chlamys glabra. It was found that, in mollusk taxonomy, the elements have unique values. In other words, element concentrations in various mollusk shells depend mainly on the taxonomic characteristics of mollusks. In various bionomic environments different element distributions of the same species are attributed to the different geochemical characters of the each environment. Data obtained in this study indicate that the organisms are the most active and deterministic factors of the environment.     

Determination of major and trace elements in European bottled mineral water — Analytical methods

A total of 1785 European bottled water samples were analyzed using standard laboratory methods. The bottled water samples were purchased in 2008 at supermarkets throughout 40 European countries. The samples were analyzed for 71 chemical parameters (As, Al, As, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Hg, Ho, I, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Nd, Ni, Pb, Pr, Rb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Tb, Te, Th, Ti, Tl, Tm, U, V, W, Y, Yb, Zn, Zr, Br⁻, HCO₃⁻, Cl⁻, F⁻, NH₄⁺, NO₂⁻, NO₃⁻, PO₄³⁻, SO₄²⁻, SiO₂, pH, and EC) by quadrupole inductively coupled emission spectroscopy (ICP-QMS, trace elements), inductively coupled plasma atomic emission spectroscopy (ICP-AES, major elements), ion chromatography (IC, anions), atomic fluorescence spectrometry (AFS, Hg), titration (alkalinity), photometric methods (NH₄⁺), potentiometric methods (pH), and conductometric methods (specific electrical conductivity, EC). A very strict quality control procedure was followed by analysing blanks, international reference materials, an internal project standard, and duplicate analyses, as well as by analysing 23 elements by both ICP-QMS and ICP-AES. Analysis of marketed bottled water from springs, wells or boreholes, apart from the evaluation of its quality with respect to inorganic elements, it may provide a cheap alternative to obtain a first impression about groundwater chemistry at the European scale.