中国大陆科学钻探（CCSD）UHP岩石石英脉中磷灰石团块独居石出溶物的U-Th-Pb化学定年

CCSD主孔榴辉岩等UHP岩石石英脉中存在团块状到不规则脉体状的磷灰石集合体,显微镜下观察发现其中存在四种出溶物:磁铁矿和赤铁矿的连生体、赤铁矿、独居石和锶重晶石;出溶物的长轴和生长方向均基本平行于磷灰石之C轴,显示它们可能是基本同时出溶的。其中独居石出溶体多为菱形到板状自形晶体,宽约6—10μm,长约50～75μm。运用CHIME化学定年方法对CCSD磷灰石团块中的独居石出溶物进行了年代学研究,获得其Th-Pb等时线年龄为202±28．3Ma,表明磷灰石团块形成于榴辉岩在折返过程中的重结晶和退变质,时代为晚三叠世。该年龄可能也代表了CCSD中UHP岩石中包裹磷灰石团块的石英脉的形成时代。     

榴辉岩磷灰石中出溶体成因的一种新解释

目前,在大别-苏鲁榴辉岩的磷灰石中已经观察到多种出溶现象,出溶体矿物主要是独居石和铁、铜硫化物,个别有硅钍石[1]、铁氧化物和重晶石[2,3].对于出溶体现象的解释,一般认为是超高压变质条件下形成的磷灰石在退变质减压、降温作用以及氧逸度fO2变化下,其中的LREE与[PO4]3-结合形成独居石,而S、Fe、Cu等元素结合形成硫化物,并沿着一定的晶格方向出溶.     

中国大陆科学钻探主孔540-600m榴辉岩中赤铁矿-钛铁矿固溶体出溶结构的特征及对榴辉岩折返动力学过程的意义

在中国大陆科学钻探主孔540-600m榴辉岩中集中发育了一种具特殊出溶结构的不透明金属矿物——具高度精细共生结构的赤铁矿-钛铁矿固溶体。在这段榴辉岩中，这种固溶体少部分以细小圆粒状包裹体分布于单斜辉石和石榴石内部，大部分则呈海绵陨铁状充填于单斜辉石和石榴石空隙之间。出溶分多个不同的期次，相对粗粒的赤铁矿质钛铁矿和钛铁矿质赤铁矿出溶片晶中又包含有更细粒的出溶片晶，在次一级的赤铁矿质钛铁矿域出溶钛铁矿质赤铁矿，同时在钛铁矿质赤铁矿域又出溶赤铁矿质钛铁矿，出溶片的大小可以从毫米级一直变化到纳米级，以至于很难测到纯的端元组分。出溶片在单个颗粒中按照平行（001）的方向定向排列，但在整个样品中则没有规律。出溶片中钛铁矿的摩尔百分数从23．80变化到89．84，反映了从不具明显磁性的赤铁矿和钛铁矿端元组分向具有强磁性的出溶体演化的过程。这样的出溶过程需要一个缓慢降温的环境，说明在超高压地体快速折返的整个过程中可能存在一个近等温降压或滞留在高温状态下（近等温等压）的阶段。这种固溶体在矿物的磁性特征方面十分特别：（1）可以包含异常强且稳定的天然剩磁；（2）所保存的剩磁即使在强的退磁磁场中也不会消退；及（3）能引起区域上显著的磁异常。因此，这种固溶体可能是导致CCSD主孔540～600m段榴辉岩较高磁化率、区域高度航磁异常及高度V、Ti异常的主要因素。赤铁矿-钛铁矿固溶体出溶结构在540～600m岩性段集中分布的现象与这一岩性段在各方面均有异常表现的奇特现象相吻合，结合前人的研究，认为赤铁矿-钛铁矿固溶体的成因与导致这段岩性段各种异常的成因有着直接的联系。赤铁矿-钛铁矿固溶体出溶结构的出溶成分和所具磁性强烈依赖于榴辉岩温压条件的变化特征，对它的继续深入研究，将会为精确限定苏鲁超高压变质带变质岩石形成中的温压变化，解释CCSD主孔附近区域的磁性异常及钒钛矿的勘探等问题起到重要的指示作用。     

中国大陆科学深钻主孔岩屑中含钠和锌的尖晶石的发现

一种含钠和锌的尖晶石矿物产于中国大陆科学深钻主孔超镁铁岩中，以出溶的方式存在于钛铁矿和磁铁矿中，长5-60μm，宽2-3μm，化学组成（wB％）为MgO17．143％-22．337％，Al2O3 63．646％～66．492％，FeO9．784％～13．924％，ZnO 1．649％-6．386wt％．Na2O 0．029％～0．219wt％。Na2O与ZnO在尖晶石中的含量呈正相关关系。经同步辐射测得其为尖晶石单晶，空间群为Fm3m，晶胞参数为a=0．83781am。根据尖晶石与钛铁矿、石榴石（pyr=56-58mol％）共生和石榴石退变为顽火辉石和镁绿泥石的特点，表明该尖晶石来自超镁铁岩，它们一起经历了至少为角闪岩相的变质作用。广泛的混溶间断现象及其所造成的出溶结构出现在氧化物中，表现为Mt-Usp、Mt-Spl及Mt-Ilm之间的交生。根据前人有关Mt-Usp和Ilm-Gk-Hem固溶体系的实验。表明主孔岩石的氧逸度相对较低，形成温度应在720℃以上。这些早期在岩浆分离结晶过程中形成的铁钛氧化物出溶体，在后来的超高压变质作用下可能发生再次固溶和因降温减压造成的出溶。     

白云鄂博矿床稀土矿物稳定同位素特征及其意义

稀土元素是白云鄂博矿床最有特色的矿产。本文在详细讨论了稀土矿物氧、碳同位素制样方法的基础上，对矿床中晚期脉、白云石型矿石、萤石型矿石中的主要稀土矿物进行了系统的氧、碳同位素分析。其中，晚期脉中的氟碳酸盐矿物的碳、氧同位素值较低，具有幔源热液结晶的特点；白云岩型矿石中氟碳铈矿δ１３Ｃ在－１．１‰～－３．４‰，δ１８Ｏ在８．６‰～１２．０‰；独居石δ１８Ｏ在５．７‰～１１．４‰，磷灰石δ１８Ｏ在６．３‰～９．４‰；萤石型矿石中氟碳铈矿δ１３Ｃ在－５．２‰～－５．８‰，δ１８Ｏ在３．６‰～５．５‰；独居石δ１８Ｏ在３．５‰～４．５‰。结合矿床地质特征分析，矿区萤石型矿石和晚期脉的形成可能与深源热液有关；而白云岩中的稀土矿化作用则表现出多源多期次的特点     

中国大陆科学钻探主孔中磷灰石的磁黄铁矿出溶结构

在中国大陆科学钻探主孔中部的榴辉岩样品B1021R642P40a、B1039R646P47a、B1046R648P4c和B1053R649P74k中,我们发现了磷灰石的磁黄铁矿出溶结构。磷灰石是该榴辉岩的主要副矿物,其自形程度较高,与石榴石共生。样品中几乎所有磷灰石均发育出溶结构,至少存在两组相互垂直的出溶棒。出溶棒形状规则,一样宽(<1μm),但长度变化大(5～50μm)。利用高分辨能谱仪测定表明,出溶棒主要由Fe和S两种元素组成。由于还不能准确地确定其Fe/S比值,初步确定其为磁黄铁矿(Fe_(1-x)S)。磷灰石由于含大量稀土元素和挥发性组分如OH、F、Cl和S,它的深循环因此可能对地球的水、硫以及其它挥发性组分的全球平衡具有重要影响。     

秦岭造山带发现新型铀多金属矿:华阳川与伟晶岩脉和碳酸岩脉有关的超大型铀-铌-铅-稀土矿床

华阳川铀多金属矿位于华北板块南缘小秦岭构造带的西段,是一个以U、Nb、Pb为主并伴生有稀有稀土元素的可综合利用的超大型矿床。矿体主要赋存于太古代TTG片麻岩套中(武家坪黑云斜长片麻岩和大月坪花岗片麻岩)。矿化与伟晶岩脉、火成碳酸岩脉和碳酸盐脉紧密共生。伟晶岩脉主要由微斜长石、石英以及黑云母、角闪石、褐帘石、榍石和独居石组成。火成碳酸岩脉主要由方解石、石英、重晶石、霓辉石、钠闪石、黑云母和磷灰石等组成。碳酸盐脉主要由方解石、石英、重晶石和沸石等组成。根据脉体穿插关系和矿物组合特征,矿化可分为伟晶岩阶段、早期碳酸岩阶段和晚期碳酸盐化阶段,伟晶岩阶段和早期碳酸岩阶段以铀铌矿化为主,晚期碳酸盐化阶段则以铅矿化为主。铀矿物以铌钛铀矿为主,晶质铀矿次之;铌矿物以铌钛铀矿为主,褐钇铌矿次之;铅矿物以方铅矿为主,白铅矿次之。此外,U、Nb还以类质同像或吸附的形式赋存于褐帘石、独居石和磷灰石等富集稀土元素的矿物中。根据含矿主岩、矿石矿物以及成矿元素组合特征,认为华阳川矿床不同于世界上其他类型的铀矿床,属于与伟晶岩和碳酸岩有关的铀-铌-铅-稀土矿床。     

中国大陆科学钻探（CCSD）高压超高压变质岩中石英脉流体包裹体初步研究

初步的岩相学和冷热台显微测温表明，CCSDHP—UHP岩石中石英脉和后期碳酸盐脉中含有3种流体包裹体：盐水溶液(NaCl-H2O)包裹体(Ⅰ类)、NaCl-CaCl2-H20(Ⅱ类)和N2-CH4纯气相(Ⅲ类)包裹体，其中Ⅰ类盐水溶液包裹体可进一步分为中高盐度盐水溶液包裹体(Ia)、中等盐度盐水溶液包裹体(Ib)和低盐度盐水溶液包裹体(Ic)，而Ⅲ类为CCSD中首次发现：Ia、Ib和Ⅱ型流体包裹体主要以原生或假次生形式赋存在榴辉岩的石英脉或石英颗粒中，在角闪岩相的片麻岩及其石英脉中均未观察到，显示它们可能主要被捕获于榴辉岩的减压重结晶或退变质阶段，而Ic型包裹体分布广泛，表明其主体可能是在超高压变质岩折返过程的最晚阶段捕获的；N2-CH4纯气相包裹体均为原生包裹体，主要呈孤立和小群状与Ia和Ib类包裹体分布于榴辉岩中条带状石英脉中，可能主要是在高压-超高压榴辉岩相变质条件下被捕获的；CCSD榴辉岩中石英脉的主体形成于板块折返有关的减压重结晶和退变质，而片麻岩中石英脉则主要来源于角闪岩相及其后期退变质作用；榴辉岩和片麻岩中石英脉流体包裹体的组成和地球化学特征存在明显区别，但它们各自相似于其寄主岩石中的石英颗粒中包裹体，说明CCSD中HP—UHP岩石在板块折返过程中释放出的变质流体没有经过大规模的迁移。     

定量确定中国大陆科学钻探工程主孔榴辉岩磷灰石中出溶体的组成:扫描电镜能谱分析(EDS)的应用

在不同类型变质岩和超基性岩的造岩矿物(如橄榄石、石榴子石、绿辉石等)中都发现了大小不一的固态出溶体。对大小仅为几个微米的出溶体,利用常规方法,电子探针、拉曼光谱等很难定量地确定它们的化学组分,严重地限制了对这些出溶体的地球化学动力学意义的认识。在最近的一系列研究中,发现榴辉岩中磷灰石含大量的出溶体,这些出溶体是平行于磷灰石C轴出溶的含铁、铜、铅等元素的硫化物。采用扫描电镜能谱分析(EDS)的点分析和线扫描技术,确定出溶体的主要组成元素,然后通过扣除磷灰石对所分析出溶域的贡献,能较准确地确定这些出溶体的化学组分,主要为FeS和FeS2。这些实验结果表明,利用扫描电镜的能谱分析(EDS)技术,通过点分析和线扫描,能够较精确地测量与母矿物之间化学成分差异较大的出溶体的化学组成。本文所提出的处理方法也适用于电子探针。     

新疆鄯善康古尔塔格金矿床地质地球化学特征及成矿模式

康古尔塔格金矿床位于天山东段。附近还有一些金矿点和金化探异常,构成长达110km、宽约5km的金矿化带。容矿岩石为一套海相火山-沉积岩系,以火山岩为主。主要岩石类型有安山岩、英安斑岩、凝灰岩、霏细岩、流纹岩夹浅变质砂岩、粉砂岩、含砾砂岩及灰岩等。金矿体呈层状、似层状,有膨胀狭缩、分支复合现象。矿体最长850m,厚0.5～11m,向下延伸380m,含金2.6～8.7(g/t)。主要金属矿物有黄铁矿、磁铁矿、赤铁矿、黄铜矿、方铅矿、闪锌矿、自然金等。脉石矿物主要为绿泥石、石英、绢云母、方解石、重晶石。     

岩溶地区现代土壤与洞穴石笋中单甲基支链烷烃与烷基环己烷对比研究

利用GC-MS（气相色谱—质谱仪）,对采自湖北清江流域和尚洞洞顶的土壤样品与洞内石笋样品进行分析,发现土壤中存在的七个系列单甲基支链烷烃在所有的石笋样品中均可以找到,呈现相似的分布模式,石笋中七个系列支链烷烃有可能来自洞穴滴水携带的土壤中的支链烷烃,但是也不能排除石笋原地生长的微生物的贡献。烷基环己烷的分布在土壤与石笋中呈现了相似的分布模式,但是主峰碳数有所变化,高碳数部分与低碳数部分的相对含量也发生了变化。主要原因可能是微生物选择性降解的结果,也有可能是土壤与石笋中微生物种类分布差异所造成的。本次研究初步显示了相对封闭稳定的洞穴沉积物与上覆土壤层中生物标志化合物的异同。      

Geogenic and anthropogenic zinc in epiphytic and terricolous lichens in Finland

At 31 sites in Finland the Zn content was determined of the epiphytic lichen Hypogymnia physodes (L.) Nyl. growing on pine and birch, the terricolous lichen Cladina spp. in pine bark, and the inner part of birch bark. The anomalous contents of Zn in H. physodes on pine and Cladina spp. in soil appeared to be strongly related to sulphide ore deposits. Anthropogenic Zn correlated closely with S and Fe in H. physodes on pine and with Fe in Cladina spp. The binding of geogenic Zn was related to iron hydroxides, and was attributed to the different uptake mechanism of S in these lichens. Elevated values of Zn in H. physodes on birch were due to both geogenic and anthropogenic sources. Zinc in pine bark increased with the Zn content in H. physodes and reached a limiting value.     

Hydrogen and carbon in solid solution in oxides and silicates

The dissolution of H₂O and CO₂ in structurally dense, nominally anhydrous and non-carbonate oxide matrices such as MgO and CaO is reviewed. H₂O and CO₂ are treated as gaseous oxide components which enter into solid solution with the refractory oxide hosts. They form anion complexes associated with cation vacancy sites. Evidence is presented that OH^? pairs which derive from the dissolution of H₂O are subject to a charge transfer (CT) conversion into peroxy moieties and molecular hydrogen, O ₂ ^2? ... H₂. Because the O ₂ ^2? moiety is small (O^?-O^? distance ≈ 1.5 Å) high pressure probably favors the CT conversion. Mass spectroscopic studies show that molecular H₂ may be lost from the solid which retains excess oxygen in the form of O ₂ ^2? , leading to the release of atomic O. The dissociation of O ₂ ^2? moieties into a vacancy-bound O^? state and an unbound O^? state can be followed by measuring the internal redox reactions involving transition metal impurities, the transient paramagnetism of the O^? and their effect on the d.c. conductivity. Evidence is presented that CO₂ molecules dissolve dissociatively in the structurally dense oxide matrix, as if they were first to dissociate into CO+O and then to form separate solute moieties CO ₂ ^2? and O ₂ ^2? , both associated with cation vacancy sites. In the CO ₂ ^2? moiety (C-O^? distance 1.2–1.3 Å, OCO angle ≈ 130°) the C atom probably sits off center. The transition of the C atom into interstitial sites is accompanied by dissociation of the CO ₂ ^2? moiety into CO^? and O^?. This transition can be followed by infrared spectroscopy, using OH^? as local probes. Further support derives from magnetic susceptibility, thermal expansion, low frequency dielectric loss and low temperature deformation measurements. The recently observed emission of O and Mg atoms besides a variety of molecules such as CO, CO₂, CH₄, HCN and other hydrocarbons during impact fracture of MgO single crystals is presented and discussed in the light of the other experimental data.     

Comparative urbanization in Ghana and Kenya in time and space

There are few inter-African country urban analyses because of the continent’s enormous size and socioeconomic diversity, language barriers, and wide variations in national and regional urban research capacity. Nevertheless, comparative urban studies are critical in understanding contemporary African urbanization. In this comparative spatial and temporal analysis of Ghana and Kenya’s urbanization, we find that both countries are urbanizing rapidly and are faced with many common urban problems. Moreover, Ghana is more urbanized than Kenya and has a larger indigenous urban imprint and a more widely dispersed urban pattern. Besides their physiographic and population conditions, we trace these countries’ convergent and divergent urban trends to their shared but unique experiences of colonialism, nationalism and globalization.     

Temporal and spatial variations in water discharge and sediment load in the Alaknanda and Bhagirathi Rivers in Himalaya, India

The Alaknanda and Bhagirathi Rivers originate in the mountainous regions of the Himalayas (Garhwal) and result in high sediment yields causing flood hazards downstream of the Ganga River and high sediment flux to the Bay of Bengal. The rivers are perennial, since runoff in these rivers is controlled by both precipitation and glacial melt. In the present study, three locations in the upper reaches of the Ganga River were monitored for 1 yr (daily observations of, more than >1000 samples) for suspended sediment concentrations. In addition, more than one hundred samples were collected from various locations of the Alaknanda and Bhagirathi Rivers at different periods to observe spatial and temporal variations in river suspensions. Further, multi-annual data (up to 40 yrs) of water flow and sediment concentrations were used for inferring the variations in water flow and sediment loads on longer time scales. In most previous studies of Himalayan Rivers, there has been a general lack of long term water flow and sediment load data. In the present study, we carried out high frequency sampling, considered long term discharge data and based on these information, discussed the temporal and spatial variations in water discharge and sediment loads in the rivers in the Himalayan region. The results show that, >75% of annual sediment loads are transported during the monsoon season (June through September). The annual physical weathering rates in the Alaknanda and Bhagirathi River basins at Devprayag are estimated to be 863 tons km⁻² yr⁻¹ (3.25 mm yr⁻¹) and 907 tons km⁻² yr⁻¹ (3.42 mm yr⁻¹) respectively, which are far in excess of the global average of 156 tons km⁻² yr⁻¹ (0.58 mm yr⁻¹).     

Discovery of Cinnabar in Soils in Hg Anomalous Zones in City and Town Areas and Their Surroundings and Its Significance

As a result of systematic study on heavy minerals in soils at city and town areas and their surroundings,cinnabar was discovered for the first time in areas of Hg anomalies in China, and it was found that the distribution of cinnabar was basically coincident in scope with that of Hg anomalies, showing that Hg anomalies were‘closely related to cinnabar. This finding provides a theoretical basis for a verification of Hg anomalies in soils in city and town areas and their surroundings, as well as evaluation of its ecological effects, and is significant to revealing the occurrence modes and origin of Hg in soils.     

Regional gravity survey and application in oil and gas exploration in China

Ground gravity survey for regional structure unit delineation and oil and gas exploration in China is addressed in this paper with examples. Gravity survey scales, coverage, technical regulations and achievements at the national level are introduced, including data processing and anomaly interpretation techniques. Bouguer anomalies of terrestrial territories of China and classification of anomalous feature zones are also described; they are well correlated with lithotectonical boundaries, fault zones, and unexposed igneous plutons. Recent study results of petroliferous sedimentary basins are presented as well, including concealed boundaries and major structures of large basins. It is concluded that gravity survey is the most effective and economic method in unveiling unexposed and deep-seated structures, targeting and delineating oil and gas-bearing sedimentary basins, and locating main trap structures within prolific basins in early stage of exploration in China. Suggestions for improving exploration of both conventional and unconventional oil and gas reservoirs in China are also given in the paper.     

煤中气孔和镶嵌结构及其在煤变质研究中的意义

河南省禹县、新密和荥巩煤田山西组Ⅱ₁煤的贫煤和无烟煤中,气孔发育。气孔形态有椭圆状（图版1）、圆状及不规则状（图版2）,有的几个气孔连在一起呈大的朵状气孔(图版3)。此外,在荥巩煤田西部无烟煤中还发育有镀嵌结构(图版4)。      

Trends in Analytical Developments and Earth Science Applications in LA-ICP-MS and LA-MC-ICP-MS for 2004 and 2005

This review of laser ablation-inductively coupled plasma-mass spectrometry includes research that employed quadrupole instruments, and single-collector and multicollector magnetic sector field instruments. The most important trend in 2004–2005 was the growing appreciation that small matrix effects in LA-(MC)-ICP-MS need to be addressed in order to produce highly precise and accurate data by the method. The issue is most acute for isotope ratio measurements that require standard-sample-standard bracketing but can also be important for certain elemental analysis. Matrix-dependent elemental and isotopic fractionations were studied from the standpoint of laser-sample interactions and the behaviour of laser-generated particles in the ablation cell, transfer tubing and ICP torch. Innovations in LA-(MC)-ICP-MS involved signal smoothing, in torch laser ablation, on-line isotope dilution and molecular oxide monitoring. Other important research was carried out on the calibration and homogeneity of various reference materials; and the exploration of mature ( in situ U-Pb geochronology) and emerging (apatite fission-track chronometry, U-Th/He thermochronology, boron/strontium/uranium-series isotopic microanalysis) applications in the Earth sciences.     

俄罗斯油气钻采废弃物处理及其利用研究

生态安全和环境保护是世界各国都非常关心的问题。地质钻探和石油天然气钻采工作中产生大量废弃物,直接影响生态安全和环境保护,给经济建设和人民生活带来很大的负面影响。俄罗斯钻探工作者对此进行了研究,取得了一定效果。他们主要采用综合处理方法和磁化处理方法。利用这2种方法,废弃物不仅可以再生,而且还可以二次使用,有一定的创新和实际意义,值得引起我们的重视,建议对此进行研究与讨论。