柱撑粘土矿物的研究新进展——新矿物材料研究综述之一

柱撑粘土矿物作为一种大层间距的多酸型层柱微孔材料,是一种性能优异的催化剂和吸附剂,本文在较全面分析前人资料的基础上,结合笔者所做的工作,对柱撑粘土矿物的制备性能表征及其应用最新研究进展进行综述与展望。     

用储层岩石抽提物的饱和烃色谱指纹识别油气层

利用储层岩石抽提物的饱和烃色 质总离子图的指纹特征判识储层的流体（油、气）类型。油层或油饱和的储层,饱和烃色 质总离子流图的特征是正构烷烃碳数分布宽,碳数分布在C₁₅～C₃₈之间,与原油样品的正构烷烃碳数分布相似;凝析气层的正构烷烃碳数分布略窄一些,碳数分布在C₁₅～C₃₅之间,低碳数（小于C₂₁）的正构烷烃相对于油层富集,高碳数（大于C₂₁）的正构烷烃丰度明显低于油层;干气层的正构烷烃碳数分布最窄,碳数分布在C₁₅～ C₂₈之间,只有低碳数的正构烷烃,高碳数的正构烷烃丰度极低。据此可用来识别油层、凝析气层和干气层,也可用于一些测井资料不全或测井质量差的老井的油气层复查、测井难以识别的火成岩油气层的识别,还可用于地层评价,为油气酸化层位的优选提供科学依据。     

湖北徐家山锑矿床铅同位素组成与成矿物质来源探讨

徐家山锑矿床位于湖北省通山县境内,矿体赋存于上震旦统灯影组和陡山沱组地层中.对采自该矿的辉锑矿进行了系统的铅同位素测定.结果表明,在徐家山矿区范围内存在两组明显不同的铅同位素组成:A组206Pb/204Pb为18.874～19.288,207Pb/204Pb为 15.708～15.805, 208Pb/204Pb为38.642～39.001, 为高放射性成因铅;B组以低放射性成因铅为特征,其同位素组成206Pb/204Pb为17.882～18.171,207Pb/204Pb为15.555～15.686,208Pb/204Pb为37.950～38.340.对应地,相关参数也明显不同,如单阶段模式年龄,A组为负值或极小的正值,而B组为636～392 Ma.铅同位素组成与某些相关参数(Δγ与Δβ、V1与V2)之间呈明显线性正相关关系.根据铅构造模式和矿石铅同位素的Δγ-Δβ成因分类图解等综合分析,A组辉锑矿的铅主要来源于赋矿围岩--震旦系海相碳酸盐岩,B组主要来源于赋矿围岩的下伏基底碎屑岩--中元古界冷家溪群浅变质岩系.研究结果不支持前人沉积-改造成因的观点,成矿物质是多来源的,部分成矿物质来自基底地层.     

Isotopes and Geochronology of the Meixian-type Pb-Zn-(Ag)Deposits,Central Fujian Rift,South China:Implications for Geological Events

Central Fujian Rift is another new and important volcanogenic massive sulfide Pb-Zn polymetallic metallogenetic belt. In order to find out the material genesis and mineralization period of Meixian-type Pb-Zn-Ag deposits, S and Pb isotope analysis and isotope geochronology of ores and wall rocks for five major deposits are discussed. It is concluded that the composition of sulfur isotope from sulfide ore vary slightly in different deposits and the mean value is close to zero with the 834S ranging from -3.5‰ to ＋5.6‰ averaging at ＋2.0‰, which indicates that the sulfur might originate from magma or possibly erupted directly from volcano or was leached from ore-hosted volcanic rock. The lead from ores in most deposits displays radioactive genesis character （206pb/204pb〉18.140, 207Pb/204pb〉15.584, 208pb/204pb〉38.569） and lead isotope values of ores are higher than those of wall rocks, which indicates that the lead was likely leached from the ore-hosted volcanic rocks. Based on isotope data, two significant Pb-Zn metallogenesis are delineated, which are Mid- and Late-Proterozoic sedimentary exhalative metailogenesis （The single zircon U-Pb, Sm-Nd isochronal and Ar-Ar dating ages of ore- hosted wall rocks are calculated to be among 933-1788 Ma.） and Yanshanian magmatic hydrothermal superimposed and alternated metallogenesis （intrusive SHRIMP zircon U-Pb and Rb-Sr isochronal ages between 127-154 Ma）.     

A laboratory study on groundwater quality and mass movement occurrence

In this study, soil samples collected from the sides of two streams with high debris flow potential at Shenmu and Fengchiou village in Nantou County, Taiwan, were used for seepage tank tests in the laboratory. While the tests were being conducted, observations were made to investigate the relationships among displacement of the slope, quality of the seepage water and occurrence of mass movement. The results showed that according to the change rate, displacement could be divided into two stages, namely, the initial failure displacement stage and primary failure displacement stage. While the displacement of the slope was in primary failure displacement stages, the probability of slope failure became much higher. Before general slope failure, electrical conductivity (EC) and sulfate ion (SO₄ ²⁻) concentration of the seepage water increased significantly. The time when EC of the seepage water started to increase rapidly was much earlier than that when displacement of the slope started to increase significantly. Therefore, from the hazard mitigation view, there will be a longer time for response if EC of the seepage water was monitored.     

Regional stratigraphy and distribution of epigenetic stratabound celestine, fluorite, barite and Pb–Zn deposits in the MVT province of northeastern Mexico

Northeastern Mexico hosts numerous epigenetic stratabound carbonate-hosted low-temperature hydrothermal deposits of celestine, fluorite, barite and zinc-lead, which formed by replacement of Mesozoic evaporites or carbonate rocks. Such deposits can be permissively catalogued as Mississippi Valley-type (MVT) deposits. The deposits studied in the state of Coahuila are associated with granitic and metasedimentary basement highs (horsts) marginal or central to the Mesozoic Sabinas Basin. These horsts controlled the stratigraphy of the Mesozoic basins and subsequently influenced the Laramide structural pattern. The Sabinas Basin consists of ~6,000-m-thick Jurassic to Cretaceous siliciclastic, carbonate and evaporitic series. The MVT deposits are mostly in Barremian and in Aptian-Albian to Cenomanian formations and likely formed from basinal brines that were mobilized during the Laramide orogeny, although earlier diagenetic replacement of evaporite layers (barite and celestine deposits) and lining of paleokarstic cavities in reef carbonates (Zn–Pb deposits) is observed. Fluid inclusion microthermometry and isotopic studies suggest ore formation due to mixing of basinal brines and meteoric water. Homogenization temperatures of fluid inclusions range from 45°C to 210°C; salinities range from 0 to 26 wt.% NaCl equiv., and some inclusions contain hydrocarbons or bitumen. Sulfur isotope data suggest that most of the sulfur in barite and celestine is derived from Barremian to Cenomanian evaporites. Regional geology and a compilation of metallogenic features define the new MVT province of northeastern Mexico, which comprises most of the state of Coahuila and portions of the neighboring states of Nuevo León, Durango and, perhaps extends into Zacatecas and southern Texas. This province exhibits a regional metal zonation, with celestine deposits to the south, fluorite deposits to the north and barite and Zn–Pb deposits mostly in the central part.     

铅锌矿山开发导致的重金属在环境介质中的积累

以连续提取法和相关性分析研究了土法冶炼锌、铅锌和矿山开采导致的重金属在废渣及环境介质土壤、溪流沉积物中的积累，并分析了其环境危害性。结果显示，贵州赫章土法炼锌导致的重金属Pb、Zn、Cd在环境介质中的积累相当高。水城杉树林铅锌矿山开采引起的重金属积累则相对较低，但也明显高于背景值；土壤和沉积物中的铁矿物对重金属有强烈的固定作用。除残渣态外，Pb、Zn在土壤、炼锌废渣中主要呈铁锰氧化物结合态，沉积物中则为碳酸盐结合态。可交换态Pb、Zn含量变异较大，但在炼锌废渣、土壤中含量明显高于河流沉积物，暗示铅锌矿开发对土壤环境的潜在危害更大。     

铅离子污染对桂林红黏土力学性质影响的试验研究

桂北地区铅锌矿产资源的开采对红黏土土层产生了不同程度的污染,为研究铅离子污染对桂林红黏土力学性质的影响,对其重塑样进行三轴不固结不排水剪切试验,测试获得了不同铅离子浓度、作用时间、围压下的应力-应变关系曲线、弹性模量、抗剪强度参数的变化规律。研究结果表明：铅离子污染对桂林重塑红黏土的力学性质有着显著的影响,随着铅离子浓度的增加,土体力学性质随之衰减,并在浓度最大值（1.0%）时达到最低;铅离子污染红黏土应力-应变曲线均呈硬化型,但是随着铅离子浓度的增大,以及围压的增大,其硬化的趋势均有所减弱;弹性模量、抗剪强度随着浓度的变化有着明显的衰减,但是抗剪强度参数在所选的作用时间梯度内其变化并不明显,说明铅离子污染能够在较短时间内完成对土体结构的主体破坏。     

基于裂缝混凝土的修正氯离子迁移模型研究

通过研究裂缝混凝土内的氯离子运移,建立了混凝土内考虑扩散、结合和电迁移场作用以及裂缝影响的氯离子迁移耦合模型。预测混凝土寿命。模型从已有试验数据中得到了较好验证。在南通盐渍土环境,运用Comsol Multiphysics软件计算混凝土内氯离子随时间和空间的分布;随裂缝宽度、深度及保护层厚度变化的混凝土使用年限变化规律。研究表明：混凝土内氯离子浓度,随时间增加而增加,增速减小;随离子侵入混凝土深度增加而减小,减速趋缓。氯离子从裂缝运移到混凝土孔隙,浓度突降。混凝土使用年限,随保护层厚度增加呈近似线性增加;随裂缝深度增加而减小;随裂缝宽度增加呈指数型函数关系。     

重金属胁迫对两种海洋饵料微藻的急性毒性效应研究

在模拟生态环境条件下研究了铜(Cu2+)、镉(Cd2+)和锌(Zn2+)3种重金属离子对2种海洋饵料微藻(青岛大扁藻(Platymonas helgolandica)和等鞭金藻8701(Isochrysis galbana 8701))的急性毒性效应,分析其对种群增长的影响,并利用透射电镜对微藻亚显微结构的变化进行分析。在实验浓度范围内,2种微藻的种群增长对3种重金属离子的急性胁迫表现出类似的变化趋势,随着胁迫浓度的增加,微藻的相对增长率均呈现出不断下降的趋势;通过比较2种微藻的48hEC50和96h-EC50发现:3种重金属离子的毒性程度为Cu2+Cd2+Zn2+,等鞭金藻8701对重金属胁迫的敏感性高于青岛大扁藻。2种微藻的亚显微结构观察显示,二者的膜结构及细胞核对Cu2+胁迫并不太敏感;与对照组相比等鞭金藻8701的色素体及贮能物质受影响较严重,而青岛大扁藻的叶绿体及淀粉粒受影响较大。