扫描核探针技术及其地学应用进展

扫描核探针技术作为一种重要的微区原位无损痕量分析手段 ,广泛应用于地学与环境、生物与医学、微电子、材料与冶金科学以及艺术与考古学等研究领域。文中简介该技术在仪器装置、分析技术到地学应用方面的新进展 ,并将之与其他微区分析技术的性能特点进行了对比 ,最后讨论了该技术的未来发展和更广泛的地学应用问题。     

ICP-MS技术在地学中的应用新进展

<正>0前言近些年来,随着地质行业的蓬勃发展,地质研究也由原来的半定量到定量研究,并且对测试仪器和方法的精度和灵敏度有了更高的要求。因此具有卓越分析性能的ICP-MS技术在地学中得到了广泛的应用。本文分别从ICP-MS在铂族元素分析、流体包裹体分析测试、锆石微区原位定年和稀土稀散痕量超痕量元素分析等几个方面,对ICP-MS技术最近几年在地质学研究中的应用做一个简要的综述。     

地学e-Science研究与实践——以东北亚联合科学考察与合作研究平台构建为例

地学e-Science被认为是继理论分析、实验观察和模拟计算之后的地学科研方法,将促进传统地学科研模式的变革,提升地学研究的效率和水平.由于地学e-Science的研究刚刚起步,国内外学者对其本质、内容、技术架构和未来发展,还缺乏一个统一、清晰的认识.认为地学e-Science的实质就是支撑地学研究的信息化环境及其在此...     

电感耦合等离子体质谱(ICP-MS)技术在地学研究中的应用

简单介绍ICP MS技术应用最新进展。着重对该技术在中国地学研究和多目标地质调查中的应用作一回顾 ,包括ICP MS技术简介和地质样品分析需求 ,稀土稀散等痕量、超痕量多元素分析 ,铂族元素分析 ,卤素等非金属元素分析 ,同位素比值分析等内容。着重对最近几年国内地质样品分析的一些新方法加以介绍。     

简述瞬变电磁法(TEM)的研究现状、进展与问题

近年来,由于电子技术的快速发展、勘查市场的旺盛需求以及瞬变电磁法(TEM)的自身优点,使得TEM方法从仪器到方法技术均获长足进展。在此,简述了TEM仪器及方法技术的研究现状与进展,总结了TEM的应用领域,分析了TEM方法目前存在的主要问题,探讨了TEM急需解决的问题及发展方向。     

地学e-Science研究与实践——以东北亚联合科学考察与合作研究平台构建为例

地学e-Science被认为是继理论分析、实验观察和模拟计算之后的地学科研方法,将促进传统地学科研模式的变革,提升地学研究的效率和水平。由于地学e-Science的研究刚刚起步,国内外学者对其本质、内容、技术架构和未来发展,还缺乏一个统一、清晰的认识。认为地学e-Science的实质就是支撑地学研究的信息化环境及其在此基础上开展的各类地学科研活动,其总体架构包括信息化基础设施、地学资源、功能服务和科研应用4个层次。基于地学e-Science的研究可以实现地学科研模式的4个转变。实践表明地学e-Science原型系统:东北亚联合科学考察与合作研究平台通过信息化技术和数字化资源改变了传统科学考察的模式,极大促进了中国、俄罗斯、蒙古3国科学家联合科学考察的效率。     

微机地学仪器的算法分析与应用

本文根据最新发展的个人仪器理论,讨论了在微机地学仪器设计中如何利用软件算法消除测量误差,实现传感器的非线性校正、数据平滑、信号分析与信息变换等方法技术,某些方法技术引用了笔者的微机地学仪器设计实例加以说明。     

地学信息图谱方法前瞻

地学信息图谱是地理学发展的新契机。地学信息图谱研究不仅局限于表现,更是一种分析方法。地学信息图谱是图形、方法和认知三者的综合与统一。从地理学自身、GIS技术和"数字地球"战略三方面分析了地学信息图谱发展的背景。通过古代阴阳理论、物理学、生物学以及传统地图学,阐述了信息分析中的图谱方法。结合信息时代的特点,阐述了地学信息图谱方法的切入点。根据地理学发展的现状,提出地学信息图谱研究的起步工作主要有三方面：区域地理单元及其等级体系;地理单元的遥感影像特征分析;地学信息的表达方法。着重讨论了地学信息图谱研究关键要解决的三方面的地理学问题：地理对象的概括、地理学基本问题的分类、地理信息及其表达。     

现代岩矿分析技术格局与展望

本文回顾了近年来岩矿分析技术的发展状况。指出地矿部在八十年代由于大型仪器的引入、使用和普及以及现代化学分析的新发展,使岩矿分析技术形成了新格局。展望未来,随着地学研究的深入发展,现代分析技术、自动分析技术、联用技术、信息管理等的推进将是当前岩矿分析技术的重要内容。同时应充分注意与边缘学科结合向其它服务领域延伸的新任务。     

数据预处理技术在地学大数据中应用

大数据时代随着数据的爆发式增长,在带来可供研究的海量数据的同时,也带来巨量的噪声和冗余数据。在地学领域,由于研究方向和技术方法手段的多样化,产生了数据量巨大和类型众多的地学数据集合。在地学信息的研究过程中,经常碰到地学信息孤岛,分图幅地学数据边界系统误差和地学文档的非结构化问题。在对地学数据进行信息的提取和挖掘之前,必须根据研究目的对地学大数据进行预处理,使冗余、复杂的大数据转为结构化、准确、可用的数据。本文以地学大数据的预处理技术为切入点,从地学数据交互标准与语义、数据调平、地质图接边和文本结构化等四个研究方面,分析阐述目前地学大数据挖掘方面存在的问题及主要的解决手段,同时也对多元数据融合在大数据中的应用进行了阐述。希望通过本文对地学大数据预处理技术的探讨,能对地学大数据的挖掘有所帮助。     

高速远程滑坡运动学研究综述

高速远程滑坡是一种危害极大的地质灾害,其形成机理与运动过程十分复杂,因此一直是滑坡研究中的难题。为此,本文综述了近几十年来国内外在高速远程滑坡的案例、机理、试验和数值模拟方面的研究成果。其中高速远程滑坡预测的数值模型有离散介质模型、连续介质模型和耦合模型。离散介质模型基于离散元法（DEM）、非连续变形分析法（DDA）和数值流形法（NMM）等,连续介质模型基于有限差分法（FDM）、有限体积法（FVM）、光滑粒子流法（SPH）、任意拉格朗日-欧拉法（ALEM）、元胞自动机法（CA）和格子玻尔兹曼法（LBM）等。离散介质模型适用于岩质滑坡,而连续介质模型适用于流动性滑坡。离散介质模型与连续介质模型相结合的耦合方法已成为高速远程滑坡数值模拟的一种发展趋势。目前,高速远程滑坡的动力侵蚀、气浪效应以及滑坡对结构的影响等问题仍是研究中的薄弱点,这些问题的试验研究相对较少,且数值模拟方法还不够成熟,可作为今后研究工作的重点。     

地应力主要测试和估算方法回顾与展望

随着人类对深部矿产资源和能源材料的需求量持续增长,深部开采问题必将成为工程界所面临的重大问题,而地应力参数的准确确定是有效解决该重大问题的基础工作之一。文章总结了目前在能源和资源开采中使用较为广泛的26种地应力测试方法,并对这些方法的基本力学原理、发展史作了简要介绍。这26种方法按照数据源途径可以分为5大类,分别为基于岩芯的方法、基于钻孔的方法、地质学方法、地球物理学方法以及基于地下空间的方法。这些方法依据满足工作需要的角度又可以分为主动法和现象分析法,对于社会基础设施建设、深部能源和资源开发,主动法的适用范围更广。不同的方法所反应的应力信息是不同的,相对而言建立在大体量岩体上的方法对于分析区域应力场更为可靠。最后文章对未来的应力测量与估算的发展远景进行了展望。     

岩土材料极限分析上界法的讨论

现行的极限分析上界法,尽管求解结果合理,但理论上却存在一些矛盾：如试验证明,关联流动法则不适用于岩土材料,而现行解法却采用了关联流动法则;传统分析中假设体积不变,但计算中却出现大于实际的体积剪胀变形;按关联流动法则,应力特征线与速度滑移线重合,但在分析中却采用速度方向与应力特征线方向成 角;实际土体破坏时,破坏面上同时存在着剪切力 和正应力 ,但在计算中却反映不出摩擦功。近年在中国日益兴起的广义塑性力学理论为岩土材料的极限分析方法提供了科学的理论基础。作者提出了基于广义塑性力学的极限分析上界法,消除了上述矛盾,并获得了正确的计算结果。通过同经典算法的比较,证明了两种方法的计算结果几乎是一致的,但现行方法计算简便,因而,可作为一种实用的计算方法。论文还对上述两种算法作了系统的分析与比较,指出了它们求解的相同点与不同点。     

Relationships among some locally conservative discretization methods which handle discontinuous coefficients

This paper presents the relationships between some numerical methods suitable for a heterogeneous elliptic equation with application to reservoir simulation. The methods discussed are the classical mixed finite element method (MFEM), the control-volume mixed finite element method (CVMFEM), the support operators method (SOM), the enhanced cell-centered finite difference method (ECCFDM), and the multi-point flux-approximation (MPFA) control-volume method. These methods are all locally mass conservative, and handle general irregular grids with anisotropic and heterogeneous discontinuous permeability. In addition to this, the methods have a common weak continuity in the pressure across the edges, which in some cases corresponds to Lagrange multipliers. It seems that this last property is an essential common quality for these methods. T.F. Russell: Partially supported by the National Science Foundation Grant Nos. DMS-0084438 and DMS-0222300.     

河流水系连通性机制及计算方法综述

河流水系连通性具有水文调蓄、保障生物迁徙通畅、改善水土环境等功能,目前主要从水文、景观和生态等方面对其进行了定义,而河流水系连通性对社会发展也发挥着重要作用,故河流水系连通性具有自然和社会双重属性,其连通性机制主要表现为纵向、横向、垂向连通性。目前主要从景观学、水文学、水力学、生态学等学科角度提出了图论法、水文-水力学法、景观法、生物法和综合指标法等计算方法,各方法有其适用性和不足,应用中须针对实际问题选择适宜方法或进行修正。河流水系连通性未来研究应综合多尺度、多领域、多学科,在研究内容上,重点开展尺度协同、连通性含义界定、响应机理及修复问题研究,在研究手段上,重点开展多方法、多技术集成问题研究。     

断裂构造遥感识别和提取方法的现状与展望

断裂构造的遥感识别、提取方法和技术具有非常重要的应用和研究价值。随着遥感及相关技术的快速发展,断裂构造的遥感解译方法也取得了较大的进展。总结了断裂构造遥感解译的必要性及其解译标志,总结了断裂构造遥感的解译方法,尤其是遥感自动提取的方法和技术,并分析了存在的问题及发展趋势。     

Magnetic method applied to mineral exploration

Developments which have led to an enormous increase in the use of magnetic surveys for mineral exploration during the past 30 years are reviewed here. Advances in instrumentation and digital compilation of data have come about largely due to the extensive use of the airborne magnetometer as a geologic mapping tool. Currently there is a growing interest in the use of the aeromagnetic gradiometer for exploration surveys in the Precambrian Shield areas. The advantages of gradiometry as a complement to total field surveys is becoming well recognized. Miniaturized electronics has reduced the cost and size of many magnetic survey instruments and ancillary equipments. Advanced compensation techniques have made it possible to make optimum use of the increased sensitivity of magnetometers for various high-resolution applications.Quantitative interpretation of magnetic data in terms of models of causative bodies has advanced largely due to the development of computerized multiparameter inversion methods. Many of these permit interpreter interaction through computer-graphic display system to impose sensible geologic constraints. Several survey contractors have the software and hardware facilities to perform various data enhancement techniques and also interactive modelling. Susceptibility mapping and magnetization mapping techniques are of great potential utility in mineral exploration. There is still a great need for studies into the relationship between rock magnetism and magnetic anomalies.     

La mesure de l'anisotropie de susceptibilité magnétique dans les flyschs: Application à la recherche des directions des paléocourants

Studies made on the anisotropy of magnetic susceptibility of artificial sediments have shown that there are correlations between the orientation of anisotropy axes and of transport directions. Thus, the analysis of parameters of anisotropy of magnetic susceptibility can constitute a means to investigate transport directions in flysch. To test this method in a natural model, the authors have made some measurements on flysch beds belonging to the “grés d'Annot complex”. The sediments have been sampled in the Contes and Peira-Cava synclines where the directions of paleocurrents have been determinated by classical methods. Results obtained both in Contes and in Peira-Cava on fine-grained detrital beds show a good agreement between directions of paleo-transport deduced from orientation of anisotropy axes and those established by classical methods on the levels showing “sole-marks”. However, in some beds of the Peira-Cava syncline, which are characterized by coarser grain size and “sole-marks” of good quality, the scattering of the directions of the anisotropy axes is very great and in some cases the measurements are not reproducible in the same sample.It appears, therefore, that the measurement of the anisotropy of magnetic susceptibility can constitute a good approach to analysing emplacement modes of fine-grained flysch deposits in which the use of classical methods is often difficult. This method of paleocurrent analysis complements the other techniques used in this field of research.     

Preparation and Measurement of Cassiterite for Sn Isotope Analysis

Increased interest in the fractionation of Sn isotopes has led to the development of several techniques for preparing cassiterite (SnO₂, the primary ore of Sn) for isotopic analysis. Two distinct methods have been applied in recent isotopic studies of cassiterite: (a) reduction to tin metal with potassium cyanide (KCN) at high temperature (800 °C), with subsequent dissolution in HCl, and (b) reduction to a Sn solution with hydriodic acid (HI) at low temperature (100 °C). This study compares the effectiveness and accuracy of these two methods and contributes additional methodological details. The KCN method consistently yielded more Sn (> 70% in comparison with < 5%), does not appear to fractionate Sn isotopes at high temperatures over a 2‐hour period and produced consistent Sn isotope values at flux mass ratios of ≥ 4:1 (flux to mineral) with a minimum reduction time of 40 min. By means of a distillation experiment, it was demonstrated that HI could volatilise Sn, explaining the consistently low yields by this method. Furthermore, the distillation generated Sn vapour, which is up to 0.38‰ per mass unit different from the starting material, the largest induced Sn fractionation reported to date. Accordingly, the HI method is not recommended for cassiterite preparation for Sn isotopic analysis.     

Conditional estimation variances: An empirical approach

One of the tasks routinely carried out by geostatisticians is the evaluation of global mining reserves corresponding to a given cutoff grade and size of selective mining units. A long with these recovery figures, the geostatistician generally provides an assessment of the global estimation variance, which represents the precision of the overall average grade estimate, when no cutoff is applied. Such a global estimation variance is of limited interest for evaluating mining projects; what is required is the reliability of the estimate of recovered reserves or, in other words, the conditional estimation variance. Unfortunately, classical linear geostatistical methods fail to provide an easy way to estimate this variance. Through the use of simulated deposits (representing various types of regionalization)the present paper reviews and discusses the effects of changes in cutoff grade and selective mining unit size on the conditional estimation variance. It is shown that, when the cutoff grade is applied to a pointsupport (sample-size)distribution, the conditional estimation variance appears to be readily accessible by classical formulas, once the conditional semivariogram is known. However, the evaluation of the conditional estimation variance seems to be less straightforward for the general case when a cutoff is applied to the average grade distribution of selective mining units. Empirical approximation formulas for the conditional estimation variance are tentatively proposed, and their performance in the case of the simulated deposits is shown. The limitations of these approximations are discussed, and possible ways of formalizing the problem suggested.