黑龙江省砂金指纹（化学成分）特征

对黑龙江省８４个砂金，７个岩金样品的化学成分进行了研究。通过Ｒ型聚类分析、探讨了不同元素之间相关性及其地质意义。通过Ｑ型聚类分析将所有样品进行分类，探讨了砂金样品与已知岩金样品之间的成因联系，并对砂金的可能原生金源的剥蚀程度进行了估计。     

用系统聚类分析方法进行水质评价

用系统聚类分析方法进行水质评价,可以根据需要进行不同级别的分类,在同一类中,各样品各分析项目的超标情况是相似的,故可算出每一类的平均超标程度,以便于研究各类水的超标原因及治理措施。 文章介绍了系统聚类方法及用于水质评价的计算原理及方法,附有两个算例,第一个用于说明计算方法,第二个实例为168个样品的分类结果,附有平面图,用于说明此种分类方法的实际效果。     

聚类分析方法及其在水文地质分析中的应用

聚类分析是研究分类问题的一种多元统计方法。在水文地质工作中,采用聚类分析方法进行含水层富水性（带）划分、地下水水质类型划分与评价等,突破传统地质学所建立的一些定性分类系统,形成一些定量的分类关系,能够取得较理想的效果     

数字地貌形态分类优化方法

地貌形态特征分类对生态环境、水文研究及地质构造分析等地学研究具有重要意义,已成为现代地貌学的一个研究热点。利用高分辨率DEM数据,以平均坡度、截面曲率、最大曲率和最小曲率等地貌形态因子为参数,构建地貌形态分类模型;基于自组织映射神经网络提出数字地貌形态分类数学优化方法,对长春地区进行地貌分类。该方法实现自动聚类分析,获得了10种地貌类型阈值,达到地貌形态特征分类要求。这种方法突破了形态参数分类方法6种地貌类型的限制,分类种类达到10种;通过SOM聚类分析,自动获取阈值,从而减少了人为主观因素的干扰。地貌形态分类取得较好效果。     

用“找异原则”进行聚类谱系图判读的新尝试

一、引言聚类分析是一种应用十分广泛的多元统计方法。在地质学领域应用尤为普遍,几乎国内开展的各项矿床统计预测工作,都进行了某种聚类分析。其目的是根据地质体的多种地质或地球化学标志的相似性,按其某种数量指标的亲疏程度,逐步聚合而进行分类。对于Q型(关于样品的)聚类而言,在样品较少的情况下,其方法简便,结果直观;但在样品数巨大的情况下,谱系图结果的分析解释,仍是一个很复杂的问题。谱系图的判读,其结果往往与专业人     

平顶山矿区矿井突（涌）水水源判别模式

对在平顶山矿区所采集的地下水样品进行了多元统计分析,以识别一些来源不清的样品归属,建立该区突（涌）水水源判别模型。选择水中６大离子为变量,对３７个水样进行了Ｑ型聚类分析和阳离子三角形分析;以聚类分析所得的结果为基础,应用判别分析方法建立了该矿区寒武系灰岩水、薄层灰岩水（Ｌ２）和砂岩水３类判别模型,并应用马氏距离作Ｆ检验和归属概率“检验”,结果表明所建立的判别模型是有效的。     

聚类分析在534铀钼矿床研究中的应用

聚类分析是对不同地质体或地质现象的某些共同属性的相似程度进行分类的一种统计分析方法,分为Q和R两种.通过对534铀钼矿床聚类分析,将矿区样品分为3组,这3组样品具有十分不同的地球化学特征:东段深部的矿化蚀变具有矿根相特征,东段浅部具有矿身相特征,而西段深部具有矿顶相特征.可以进一步推断,西段深部具有较好的找矿前景.     

区域化变量的空间聚类分析

传统的聚类分析方法利用数据对平均值的偏差，研究变量之间的相互关系。当它应用于区域化变量的分类时，因缺乏对区域化变量的空间结构的考虑，对合理解释区域化变量之间的相互关系不利。空间聚类分析方法比较好地解决了这个问题。本文介绍了该方法的基本原理及其算法，并说明了它在非条件模拟及在某矿区中的应用情况     

跨采巷道围岩结构稳定性亚分类及其应用

建立了反映跨采巷道具体稳定状态的围岩结构稳定性指标,以实测资料为样本确定出指标权值,采用模糊ISODATA 聚类分析方法得到结构稳定性亚分类模式,提供了结构稳定性实用分类方案,可应用于跨采巷道稳定性预测与支护设计。     

基于数据挖掘的M地区低渗透储层评价

文章以M地区为研究对象,针对该区实际地质情况,基于孔隙度、渗透率等测井资料,运用多元统计中的R型因子分析、判别分析及数据挖掘中的聚类分析,对储层进行合理的分类,得出储层空间的展布规律,并建立定量的评价标准。结合实际产能资料验证,认为该方法在储层评价中是可行的。     

ICP-MS测定地质样品中37个元素的准确度和长期稳定性分析

对Elan6100DRC型ICP-MS近五年来所测得的国际地质标样BHVO-1(玄武岩)和AGV-1(安山岩)中的37个元素的测定值以及仪器灵敏度的长期漂移情况进行了统计分析(共计146次)。结果表明,几年来ICP-MS所测数据的长期稳定性和准确度都较好,除个别元素Li(BHVO-1)、Be(BHVO-1))、Cr(AGV-1)、Cs(BHVO-1)和Pb(BHVO-1)的相对误差(与参考值比较)接近或略大于10%外,绝大多数元素的相对误差和相对标准偏差(RSD,测定值之间,n=146)都在5%以内;仪器灵敏度并不是随着时间一直往下漂,有的是往上漂的,也有上下漂的,即使是在同一时间内,有的元素灵敏度往上漂,而有的往下漂。常用的内标法无法较好校正这种漂移,而需要采用内外标相结合的校正方法。不同批次,210个各种地质样品中Rb、Sr、Zr和Nb的XRF和ICP-MS分析结果对比情况表明,绝大多数样品中Rb、Sr、Zr和Nb的ICP-MS和XRF的测定值的相对误差小于10%。以上的分析结果表明,我们实验室所建立的以密闭高温高压消解技术为样品前处理方法,以模拟地壳样品中元素天然丰度比的基体匹配校正标准溶液为外标和以Rh为内标结合外标校正的ICP-MS多元素分析方法具有非常好的准确度和长期稳定性。     

Neutron Activation Analysis, Atomic Absorption and X-Ray Fluorescence Spectrometry Review for 2003

This review for the year 2003 deals with three relatively well-established, mature, analytical techniques (neutron activation analysis, atomic absorption spectrometry and X-ray fluorescence spectrometry) that nevertheless remain very important for the characterisation of geological and environmental samples. Developments in neutron activation analysis included modification to the technique in relation to the determination of platinum-group elements, as well as consideration of sample size in ore grade estimation. A considerable body of literature was published on the application of atomic absorption spectrometry in the analysis of environmental samples. Many of these proposed technical and methodological improvements, notably in extraction procedures. X-ray fluorescence spectrometry saw developments in in situ analysis, synchrotron micro-XRF (μ-SRXRF) and a confocal X-ray set-up for 3D elemental imaging. XRF technologies were used in the analysis of geological samples, reference materials, glasses, solutes and environmental materials.     

Correspondence cluster analysis and its application in exploration geochemistry

Correspondence cluster analysis, developed in this paper, regroups the main advantages of correspondence analysis and cluster analysis. The output of the method, correspondence cluster dendrograms, shows clearly the relationships between variables, between samples, and between variables and samples, on a single diagram. The technique has been applied successfully to distinguish geochemical anomalies from background, to recognize types of anomalies, to study the geochemical characteristics of deposits, etc. Several practical examples presented in this paper show that the method can be used to classify elements and samples into meaningful groups, and that the geochemical character of each sample group can be interpreted in terms of the corresponding element group. The results are consistent with the geological situations at hand, and are usually more elucidating than other classification methods.     

Laser Ablation ICP-MS Analysis of Geological Materials Prepared as Lithium Borate Glasses

A simple, rapid and precise method is described for determining trace elements by laser ablation (LA)-ICP-MS analysis in bulk geological materials that have been prepared as lithium borate glasses following standard procedures for XRF analysis. This approach reliably achieves complete sample digestion and provides for complementary XRF and LA-ICP-MS analysis of a full suite of major and trace elements from a single sample preparation. Highly precise analysis is enabled by rastering an ArF excimer laser (λ= 193nm) across fused samples to deliver a constant sample yield to the mass spectrometer without inter-element fractionation effects during each analysis. Capabilities of the method are demonstrated by determination of twenty five trace elements (Sc, Ti, V, Ga, Rb, Sr, Y, Zr, Nb, Cs, Ba, REE, Hf, Ta, Pb, Th and U) in a diverse range of geological reference materials that includes peridotites, basalts, granites, metamorphic rocks and sediments. More than 90% of determinations are indistinguishable from published reference values at the 95% confidence level. Systematic bias greater than 5% is observed for only a handful of elements (Zr, Nb and U) and may be attributed in part to inaccurate calibration values used for the NIST SRM 612 glass in the case of Zr and Nb. Detection limits for several elements, most notably La, are compromised at ultra-trace levels by impurities in the lithium borate flux but can be corrected for by subtracting appropriate procedural blanks. Reliable Pb analysis has proved problematic due to variable degrees of contamination introduced during sample polishing prior to analysis and from Pt-crucibles previously used to fuse Pb-rich samples. Scope exists for extending the method to include internal standard element/isotope spiking, particularly where integrated XRF analysis is not available to characterise major and trace elements in the fused lithium borate glasses prior to LA-ICP-MS analysis.     

Condensing multi-element reconnaissance geochemical data from south Greenland using empirical discriminant analysis

Empirical discriminant analysis classified multivariate data from 2174 geochemical reconnaissance samples from South Greenland, so that they were related to known geological units or characterized as outliers. Training sets, comprising 514 samples from 14 geologic units were selected in order to reflect only the background conditions of each geological unit. A smoothing parameter of 0.5 maximized correct classification of the training sets and extracted a reasonable number of outliers (289, 13% of the samples) representing geographically grouped anomalies. Plots of the geochemical samples classified into the geological units corresponded well to the geological map.Q-mode cluster analysis classified the 289 outliers into 30 groups with different element associations. All types of mineral occurrence known in South Greenland could be recognized amongst the clusters. For example, there were seven clusters which were characterized by samples with high U values and different associated elements each one related to a different type of U mineralization. Another cluster containing samples with high Zr, Nb, and Y values reflects recently discovered pyrochlore mineralization. Other clusters were explained on the basis of geological units which were too small to be mapped or included amongst the training sets.Empirical discriminant analysis successfully reduced the multivariate data to one map, which made it easier to evaluate the varying element levels over the different geological units. Incorrectly classified samples require follow-up in order to appraise the accuracy of the geological mapping. Classification of the outliers by cluster analysis assists both in identifying samples influenced by mineral occurrences and in predicting the type of mineralization to be expected, thereby substantially aiding in the selection of areas for mineral exploration.     

ICP-MS在新疆、青海区调样品测定中的应用

本文以敞开式四酸溶样,电感耦合等离子体质谱测定了新疆、青海区调样品中的Co、Mo、W、Pb等元素,并把ICP-MS、ICP-AES和XRF三个大型仪器对新疆卡克-色帕巴衣地区样品的测定结果进行了比较,确定了区调样品元素分析方法的配套方案,并对溶样过程进行了一系列的优化,其方法检出限和精密度均符合DZ0130.4-2006及补充说明中1﹕5万化探样品标准要求。经国家标准物质验证,结果与标准值相符。优化的分析方法快速灵敏度高,能用于地球化学填图计划中分析测试任务, 同时也用于日常大规模多元素分析。     

Geochemical Baselines of Nickel and Chromium in Various Surficial Materials in the Barents Region, NW Russia and Finland

The geochemical baselines of nickel and chromium were studied from the data produced by the Barents Ecogeochemistry project, a large international regional geochemical mapping exercise. The project surveyed major and trace element distributions in stream water, organic and mineralogically-modified soil horizons, and terrestrial moss in the northwestern part of Russia and in Finland. Other materials were collected during the pilot phase and later from thirty special sites. The results on respective materials by XRF, ICP-MS and ICP-AES showed that both geological and anthropogenic factors have an influence on the geochemical baseline concentrations of Ni and Cr in organic soil and stream water. The main explanation of the observed distribution patterns in terrestrial moss is human activity, but geological factors can also affect the baselines. The variation of geochemical baselines in the mineral-rich soil horizon depends only on variations in bedrock. The mineralogy of samples mainly controls the leachability properties of soil samples.     

稀土稀有稀散元素现代仪器测试全新方法的建立

本文系统总结了自2011年以来在三稀矿产实验测试方面取得的新进展。重点介绍了离子相稀土单元素浸泡提取实验研究、稀土原产地Nd同位素与微量元素示踪技术研究、离子吸附型稀土样品野外现场快速定性定量手持X射线荧光(XRF)分析研究成果。结果表明,采用25%硫酸铵浸泡提取,电感耦合等离子体光、质谱(ICP- AES、ICP- MS)测定,可以清晰反映出各稀土元素的浸泡提取率;采用高精度多接收电感耦合等离子体质谱仪(MC- ICP- MS)进行稀土矿石中Nd143/Nd144同位素比值测定,其比值差异可以示踪不同稀土矿石产地;通过精确测试分析不同产地稀土精矿样品中的稀土和其他微量元素含量,并进行数据相关性分析和数据分类分析,通过Y、Be和Bi三种元素含量的比较,可以判断稀土精矿来源;野外现场快速分析,20分钟可完成1件样品测试,不仅可定性判断是否为离子吸附型稀土,同时可定量各离子相稀土单元素含量,与室内精确分析结果符合性良好,可为我国离子吸附型稀土矿床的找矿快速筛查提供技术支撑。 同时介绍了混合酸微波分解样品- 电感耦合等离子体光、质谱(ICP- AES、ICP- MS)同时测定钨矿石、钼矿石、铌钽矿石中的多种稀有稀散稀土元素含量的方案。该方案的特点在于采用了耐氢氟酸体系,尤其对高含量W、Nb、Ta样品更具优势,否则易产生水解,导致测定结果系统偏低。同时梳理总结了我国常见三稀矿石地质样品的特点,针对不同矿种、不同矿床样品类型与基体特点,以及所测试元素种类的不同,研究建立了专门针对“稀有、稀散、稀土元素”现代仪器分析的10个全新的配套方法及其相应的技术指标(准确度、精密度、检出限),可满足地质矿产实验室测试质量管理的规范要求,而且为我国三稀金属矿产资源的战略调查、国家重点研发计划“深地锂资源探测”和四川甲基卡等地找矿突破做出了贡献。     

X射线荧光光谱法分析地质样品的应用技巧

X射线荧光光谱法(XRF)具有制样简单、绿色环保、可同时测定多个元素等特点,被广泛应用于勘查地球化学分析领域中,其中粉末压片XRF是快速经济的主导方法。然而在大批量实际样品测试中,如果分析者选择测量条件不当或者校正标准曲线不合理,就会导致测量结果的粗大误差甚至测出不合逻辑的数据。本文对地质样品中的主要元素在测试中容易出现的技术问题作一具体分析:以钒元素为例,用实验说明探测器的选择对于测量结果的重要性,采用SC探测器可将V Kα线与Ti Kβ线分开,而采用SC+PC探测器两元素的谱线发生重叠;以硅酸盐中铁元素为例,描述了不同的回归标准曲线对测量结果的影响;对地质样品中低含量铌、钽的测定,标准曲线要根据实际情况合理回归,并将测试后的样品与化学方法对照,结果相符。同时提出了硅酸盐、碳酸盐等地质样品的测量问题。对于土壤、水系沉积物、岩石地质样品,一些元素之间会产生相互干扰,以常见的造岩元素钛为例,用实验证明铝和铁对钛的谱线确实有增强和吸收效应;对于常见的碳酸盐类样品,氯和铬的测量要考虑氧化钙的吸收增强效应,必须添加氧化钙作为其吸收增强校正项,才能保证测量结果可靠。针对硫元素的测定,除了受到硫赋存状态的影响,样品污染问题也是影响因素之一,需要避免空气、实验室环境以及分析过程中对样品的污染。本文针对一些典型元素XRF分析提出的具体测量方案,应用于实际地质样品测试可以获得满意的效果。     

Multiple discriminant analysis of the Drava River alluvial plain sediments

Three discriminant function models are raised and cross-compared in order to distinguish geochemical patterns characteristic for the Drava River floodplain sediments. Based on data representing total element concentrations in samples collected from alluvium (A), terrace (T), and unconsolidated bedrock (B) at the border of a floodplain, four element clusters emerged accounting for discrimination between the referred groups of sediments. The most prominent is contaminant/carbonate cluster characteristic for alluvium. The other two are: silicate cluster typical for unconsolidated geological substrate (Neogene sedimentary rocks); and naturally dispersed heavy metal cluster separating terrace from the former two groups. Models introducing depth intervals and single profiles as grouping criteria reveal identical sediment-heavy metal matrices. The second important issue of this paper is possibility of reclassification of samples originally assigned to one of the a priori defined groups of sediments, based on established geochemical pattern. The mapped geological units can be reconsidered by the post hoc assignments to a different group if geological border between alluvium and terrace or between terrace and bedrock can not be established geologically with absolute certainty.