Isotope Dilution MC-ICP-MS Rare Earth Element Analysis of Geochemical Reference Materials NIST SRM 610, NIST SRM 612, NIST SRM 614, BHVO-2G, BHVO-2, BCR-2G, JB-2, WS-E, W-2, AGV-1 and AGV-2

We present data for the concentrations of eleven rare earth elements (La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Er, Yb, Lu) in eleven international geochemical reference materials obtained by isotope dilution multi-collector inductively coupled plasma-mass spectrometry (MC-ICP-MS). We have analysed both rock powders and synthetic silicate glasses, and the latter provide precise data to support the use of these as reference materials for in situ trace element determination techniques. Our data also provide precise measurements of the abundance of mono-isotopic Pr in both glasses and powders, which allows more accurate constraints on the anomalous redox-related behaviour of Ce during geochemical processes. All materials were analysed in replicate providing data that typically reproduce to better than one percent. Sm/Nd ratios in all these materials also reproduce to better than 0.2% and are accurate to < 0.2% and can thus be used as calibrants for Sm-Nd geochronology. Our analyses agree well with existing data on these reference materials. In particular, for NIST SRM 610, USGS BHVO-2, AGV-1 and AGV-2, our measured REE abundances are typically within < 2% (and mostly 1%) of REE concentrations previously determined by isotope dilution analysis and thermal ionisation mass spectrometry, consistent with the higher degree of precision and accuracy obtained from isotope dilution techniques. Close agreement of results between basaltic glass reference materials USGS BHVO-2G and BCR-2G and the BHVO-2 and BCR-2 powders from which they were created suggests that little fractionation, concentration or dilution of REE contents occurred during glass manufacture.     

基于地学G~4I系统的元数据分类方法

以实现空间数据的标准化为前提,对空间数据库中元数据管理系统的作用和分类原则进行了探讨,指出了传统的分类方法对于以矿产资源预测为目标的地学系统而言存在着弊端。需要结合矿产资源预测的特点,对空间数据库建设中元数据的分类原则进行补充,提出了面向客户应用即按矿产资源预测目标进行分类,实现对空间数据查询的高效利用。该方法可以在地学G4I系统中得以实施和应用。     

Analysis of oil lens removal by extraction through a seepage face

Removal of LNAPL (oil) from an aquifer is described using a multiphase flow model. At the well boundary seepage face conditions are imposed. These conditions are implemented in a numerical model and withdrawal in a twodimensional domain is simulated for two different geometries of the oil lens and for varied values of the physical parameters. Assuming vertical equilibrium, the oil flow equation is reduced by vertical integration. The well boundary condition is approximated by imposing zero oil lens thickness. Similarity solutions of the reduced equations for the two geometries show good agreement with the numerical results in most cases.     

Distance determination and low-resolution spectroscopy of the planetary nebula M1-79

In this paper we present the first individual distance to the Galactic planetary nebula (PN) M1-79 determined using the reddening–distance method. Our result is 2.7 ± 0.9 pc (i.e. an accuracy of ≈ 30 per cent). By means of optical low-resolution spectroscopy spanning a usable range of ≈ 3650–7100 Å, the chemical composition of this PN is studied. Elemental abundances are given for O, N, and Ne, along with ionic abundances for several ions for three different regions within the nebula. The ionic abundances can be attributed to the effects of ionization stratification. There is no evidence for internal variations of O and N. From its chemical composition, morphology and kinematics, M1-79 is most probably a type I PN.     

地球节律的成因

地球节律主要受地球内部能量间歇性的释放所控制。旋转系统有不同于非旋转系统的位能、热能和旋转能的相互转换方式。在重力分异和热对流过程中，地核不仅有巨量热能，而且有巨量的旋转能和放射性蜕变能。这是地球能量释放的内因。天文因素使地球内核周期性地南北振动，使地球轨道、体积，形状、自转速度、公转速度和差异旋转状态周期性地变化。这是地球能量间歇性释放的外因。对作差异旋转的内核而言，万有引力常数Ｇ的变化可以改变太阳辐射量和太阳系体积，影响核幔的角动量交换和地壳地幔容积，造成热幔柱的形成与喷发，控制了核幔边界的能量交换过程。这是天文周期与地质旋回一一对应的原因，也是地球节律产生的根本原因。这使人们可以从天文周期预测地质变动。     

吉林省1∶20万数字地质图空间数据库的应用

1∶20万数字地质图空间数据库中存在着大量的地质矿产信息,有效地利用这些数据进行空间分析,研究矿产与控矿因素之间的关系,总结找矿地质特征,利用GIS系统可非常快捷、方便的在成矿预测工作中起到十分重要的作用。     

GNSS多系统集成的兼容性问题

分析了GNSS多系统组合导航定位的优势,论证了GPS/GLONASS/GALIEO 系统集成的兼容性,并阐述了相应的归算模型,最后探讨了GNSS兼容机的关键技术,为实现多系统组合导航提供了一定的理论依据.     

G217天山公路典型泥石流沟危险性评价研究

泥石流是新疆天山公路的主要地质灾害之一。在泥石流危险度评价模式的基础上,结合泥石流对公路的作用特点及危害程度,建立了天山公路泥石流危险度评价理论体系。此理论在天山公路泥石流危险度评价中得到了很好的验证。同时,此理论体系对公路泥石流危险度量化指标和分级评判标准,具有极大的使用价值。运用灰色关联法进行天山公路典型泥石流沟危险度计算后发现,其计算值离异程度小,可靠性强,结果较为理想。这些评价参数最终为泥石流病害治理提供了一个很好的指导。     

关于VTI介质中多分量转换波地震数据采集的最佳接收时窗

以P_P波时窗和P_SV波时窗的交叉部分作为VTI介质中P_P波、P_SV波联合采集的最佳时窗,在有效时窗内通过基于VTI介质的射线追踪法确定每个反射点的P_P波、P_SV波射线路径和相角,求解Zoeppritz方程得出P_SV波与P_P波反射系数(或透射系数)的比值,并将该比值的绝对值定义为控制因子G. 以G值作为控制VTI介质中P_P波、P_SV波联合采集观测系统设计的主要参数,通过分析G值确定检波器位置的最佳接收时窗,得出优化VTI介质中多分量转换波地震数据采集的接收时窗的方法.