新疆东昆仑鸭子泉蛇绿岩的基本特征及其大地构造意义

鸭子泉蛇绿岩位于新疆东昆仑祁漫塔格山系中部, 与阿尔金断裂平行产出, 由超基性岩、基性岩和拉斑玄武岩等组成。它侵位于早石炭世含放射虫的深海沉积物中, 可能代表了东昆仑祁漫塔格地区晚古生代的板块俯冲带。蛇绿岩可能来源于俯冲带附近的由小型扩张中心形成的次生洋壳, 之后由于消减作用, 侵位到深海沉积物中, 形成了造山带中的蛇绿岩。     

东昆仑祁漫塔格山西段鸭子泉志留纪火山岩特征

在新疆阿牙克库木湖幅一比二十五万区域地质调查中，于东昆仑祁漫塔格山鸭子泉构造混杂岩带中发现大量以蚀变玄武岩、蚀变玄武安山岩、蚀变安山岩及蚀变辉长岩、蚀变闪长岩为主的中基性火成岩，其呈大小不一的岩片岩块存在于构造混杂岩带内。通过岩石学、岩石地球化学的研究其属钙碱性岩系的玄武岩-安山岩；具有稀土总量较低、轻稀土弱富集、重稀土分馏不明显、稀土元素配分曲线呈右倾型、大离子亲石元素富集、Nb、Ti等元素亏损的特征，显示其形成于与俯冲作用有关的岛弧环境；依据同位素测年资料和地质构造演化确定该岛弧火山岩就位于志留纪，这对东昆仑地区的地质构造演化具有重要意义。     

东昆仑西段祁漫塔格群的重新厘定

通过区域地质调查和研究,认为前人所建立的的祁漫塔格群或滩间山群包括了不同时代的浅变质碎屑岩、中酸性火山岩及基性-超基性岩。根据在东昆仑原划奥陶系祁漫塔格群第一亚群(下部碎屑浊积岩)中采集到早志留世笔石化石组合(这是首次证实东昆仑地区存在志留系地层)及同位素测年资料(鸭子大板火山岩年龄),其时代包含了奥陶纪、志留纪和三叠纪等,根据中国地层指南及中国地层指南说明书和地层清理,对祁漫塔格群进行了解体,将其重新厘定为奥陶纪滩间山群(OT)、志留纪白干湖岩组(Sb)弧后盆地复理石沉积和鸭子泉组(Sy)岛弧火山岩、石炭纪鸭子大坂硅质岩(S i)、三叠纪鄂拉山组(T3e)、蓟县纪狼牙山岩组(Jx l)和南华—奥陶纪阿牙克库木湖蛇绿混杂岩[(N h—O)aΣ]。该成果对于祁漫塔格地区早古生代地层划分对比、构造演化提供了重要新证据。     

祁漫塔格找矿远景区地质组成及勘查潜力

祁漫塔格位于东昆仑山东端。近年来,找矿成果显著,相继发现了白干湖大型钨锡矿床,以及具有大型远景的卡尔却卡铜多金属矿床、维宝铅锌矿床和长清铁矿床等,原发现的迪木那里克铁矿也新增资源量,构成大型磁铁矿矿床。这些矿床的发现展示了祁漫塔格巨大的找矿潜力,已成为中国最重要的金属矿产勘查开发接替基地之一。祁漫塔格地质上处于东昆仑、阿尔金构造带和柴达木地块等几个重要构造单元交汇的构造结上,经历了复杂的地质构造演化过程。对它的理解实际是对东、西昆仑及阿尔金构造带构造演化和相互之间关系的认识,也必然涉及柴达木地块与塔里木地台之间的演化关系。就目前资料,祁漫塔格可划分为4个主要成矿期:中元古代沉积变质型磁铁矿和SEDEX型维宝铅锌矿;中奥陶世与镁铁-超镁铁层状侵入岩有关的岩浆钛磁铁矿;志留纪末矽卡岩-石英脉型钨锡矿、铁矿;中晚三叠世斑岩-矽卡岩型铜多金属矿。它们分别代表了区域不同构造演化阶段不同地质单元的产物。现今祁漫塔格的构造格架是多期构造演化拼贴的结果。成矿分布上呈"八字型"构架,以鸭子泉白干湖断裂为界,东、西翼构成了不同的成矿组合。因此,应以两翼为重点,加快勘查的进程。     

中昆仑北部古生代构造岩浆作用及其演化

对地质研究较薄弱的中昆仑北部开展了古生代构造地层格局、构造变形及构造样式、古生代花岗岩区域分布及其地球化学特征、祁漫塔格群火山岩地球化学及其区域对比等研究,认为祁漫塔格群属寒武－早志留世,早古生代祁漫塔格地区可能不存在成熟大洋,而是以大陆裂谷或初始洋盆为特征;早古生代晚期祁漫塔格山北部被动大陆边缘转化为活动大陆边缘,沿鸭子泉－祁漫塔格主脊断裂汇聚闭合;晚古生代,早期以求勉雷克花岗穹隆为核心南北简单剪切滑覆;晚期沿昆中俯冲碰撞,昆中断裂以北地区转化为活动大陆边缘,古特提斯洋闭合。     

新疆东昆仑祁漫塔格地区上三叠统火山岩岩石成因初探

新疆东昆仑祁漫塔格地区分布着一套上三叠统、喷发韵律明显的陆相火山岩和火山碎屑岩,它们起源于地下深部富集稀土元素的异常地幔,经历了一次从基性－中性－酸性的岩浆连续演化过程,是东昆仑构造演化转折期的产物。     

东昆仑造山带不同蛇绿岩带的厘定及其构造意义

在野外填图和室内地球化学研究的基础上,对东昆仑造山带蛇绿岩重新进行了厘定,并对本区构造演化进行了探讨,把东昆仑造山带蛇绿岩划分为４个带,从南到北分别为：阿尼玛卿蛇绿岩带、塔妥蛇绿岩带、清水泉蛇绿岩带、乌妥蛇绿岩带,它们在围岩的时代、构造样式及围岩变质程度,地球化学等方面明显差异。     

新疆东昆仑阿牙克岩体地球化学与^40Ar／^39Ar年代学研究及其大地构造意义

阿牙克岩体出露在新疆东昆仑阿牙克库木湖北侧的祁漫塔格山西段,侵入在早古生代低绿片岩相蛇绿混杂岩即“祁漫塔格群”之中。岩体地球化学特征显示其可能形成在伸展构造环境,角闪石的~(40)Ar/~(39)Ar坪年龄为420±4Ma;等时年龄为416±21Ma,证实早古生代末期东昆仑地区已从挤压构造体制转化为伸展构造体制,表明昆仑山具有多期造山作用叠合的大地构造特征。     

东昆仑祁漫塔格山南缘黑山蛇绿岩的发现及其特征

在新疆阿牙克库木湖幅1：25万区域地质调查中，于东昆仑祁漫塔格山南缘黑山新发现的蛇绿岩主要由堆晶杂岩和大洋拉斑玄武岩残片组成。其具有构造变形弱，蛇绿岩保留厚度较小的特点。拉斑玄武岩具低钾、低钛、富镁，轻、重稀土分馏不明显，大离子亲石元素正常—弱富集、高场强元素弱—强烈富集的特征。综合研究得出黑山蛇绿岩形成于南华—奥陶纪，构造就位于志留纪—早中泥盆世。     

祁漫塔格地区铁多金属矿床成矿特征及成因探讨

祁漫塔格地处东昆仑造山带西段,该区建造组成丰富,断裂构造发育,断层构造以北西西走向为主,华力西-印支造山旋回中酸性侵入岩浆活动强烈.在综述祁漫塔格地区成矿地质背景基础上,通过对区内肯德可克铁钴铋金矿床、野马泉铁锌矿床和迪木那里克典型铁矿床地质特征分析,并以肯德可克矿床为例,对比了不同成因类型铁矿床中磁铁矿的化学成分组成...     

Wavelength-dispersive X-ray fluorescence spectrometric determination of Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites

Komatiites are mantle-derived ultramafic volcanic rocks. Komatiites have been discovered in several States of India, notably in Karnataka. Studies on the distribution of trace-elements in the komatiites of India are very few. This paper proposes a simple, accurate, precise, rapid, and non-destructive wavelength-dispersive x-ray fluorescence (WDXRF) spectrometric technique for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in komatiites, and discusses the accuracy, precision, limits of detection, x-ray spectral-line interferences, inter-element effects, speed, advantages, and limitations of the technique. The accuracy of the technique is excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Zr, Nb, Ba, Pb, and Th and very good (within 4%) for Y. The precision is also excellent (within 3%) for Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th. The limits of detection are: 1 ppm for Sc and V; 2 ppm for Cr, Co, and Ni; 3 ppm for Cu, Zn, Rb, and Sr; 4 ppm for Y and Zr; 6 ppm for Nb; 10 ppm for Ba; 13 ppm for Pb; and 14 ppm for Th. The time taken for determining Sc, V, Cr, Co, Ni, Cu, Zn, Rb, Sr, Y, Zr, Nb, Ba, Pb, and Th in a batch of 24 samples of komatiites, for a replication of four analyses per sample, by one operator, using a manual WDXRF spectrometer, is only 60 hours.     

高压微波消解法测定醋酸纤维过滤器采集的微尘粒子中的砷镉钴铬铜铁锰镍铅钒锌

最新的流行病学研究表明,空气中较高浓度的悬浮细颗粒可能对人类的健康有不利的影响。根据该项研究显示,由于心脏病、慢性呼吸问题和肺功能指标恶化而导致死亡率的升高与细尘粒子有关。这些研究结果已经促使欧盟于1999年4月出台了限制空气中二氧化硫、二氧化氮、氧化氮、铅和颗粒物含量的法案(1999/30/EC),对各项指标包括对可吸入PM10颗粒的浓度提出了新的限制性指标。PM10颗粒是指可以通过预分级器分离采集的气体动力学直径小于10μm的细颗粒。目前研究的兴趣重点逐步偏向PM2.5这些更细微颗粒物,PM2.5这种颗粒物对健康有明显的不利影响。在欧盟指令2008/50/EC中,对PM10和PM2.5都提     

Isotopic systematics of He,Ar, S,Cu, Ni,Re, Os,Pb, U,Sm, Nd,Rb, Sr,Lu, and Hf in the rocks and ores of the Norilsk deposits

This paper reports the first results of a study of 11 isotope systems (³He/⁴He, ⁴⁰Ar/³⁶Ar, ³⁴S/³²S, ⁶⁵Cu/⁶³Cu, ⁶²Ni/⁶⁰Ni, ⁸⁷Sr/⁸⁶Sr, ¹⁴³Nd/¹⁴⁴Nd, ^206–208Pb/²⁰⁴Pb, Hf–Nd, U–Pb, and Re–Os) in the rocks and ores of the Cu–Ni–PGE deposits of the Norilsk ore district. Almost all the results were obtained at the Center of Isotopic Research of the Karpinskii All-Russia Research Institute of Geology. The use of a number of independent genetic isotopic signatures and comprehensive isotopic knowledge provided a methodic basis for the interpretation of approximately 5000 isotopic analyses of various elements. The presence of materials from two sources, crust and mantle, was detected in the composition of the rocks and ores. The contribution of the crustal source is especially significant in the paleofluids (gas–liquid microinclusions) of the ore-forming medium. Crustal solutions were probably a transport medium during ore formation. Air argon is dominant in the ores, which indicates a connection between the paleofluids and the atmosphere. This suggests intense groundwater circulation during the crystallization of ore minerals. The age of the rocks and ores of the Norilsk deposits was determined. The stage of orebody formation is restricted to a narrow age interval of 250 ± 10 Ma. An isotopic criterion was proposed for the ore-bearing potential of mafic intrusions in the Norilsk–Taimyr region. It includes several interrelated isotopic ratios of various elements: He, Ar, S, and others.     

硅酸盐中铁、锰、钛、钙、钾、磷、硅、铝、镁、钠、锶、铷、钡的X-射线荧光光谱定量测定

本文介绍样品经四硼酸锂熔融制成玻璃小饼。采用Lachance模式和理论a系数来校正元素间的效应,由3080E型X-射线荧光谱仪和DF-350B数据处理系统完成硅酸盐中十三个项目的测定。     

硅酸盐类样品中硅、铁、铝、钛、锰、钙、镁、钾、钠和磷的x射线荧光光谱测定

本文拟定了一种以熔融法制备样片,用X射线荧光光谱测定硅酸盐类样品中Si、Fe、Al、Tj、Mn、Ca、Mg、K、Na、P等元素的分析方法。在对不同靶材X光管和分光晶体实验对比的基础上,选择了最佳的测量条件。该法具有快速、准确,测量范围广,检测限低,价格便宜等优点。经过近百个各种类型标样或管理样品的分析对比表明,本法不仅适用于硅酸盐类岩石样品的分析,还适用于铁矿、铝土矿、碳酸盐类岩矿样品以及水泥、耐火材料等样品的分析。     

Viscous, cohesive, non-Newtonian, depositing, radial slurry flow

Mining induced subsidence can significantly affect mining costs where major surface facilities and natural environment need to be protected. Overburden grout injection is a technology used to control coal mine subsidence by injecting the mine waste material extracted from the coal back into the inter-burden rock during longwall mining. The flowing slurry is here categorised as a nonlinear viscous cohesive (Bingham plastic) fluid. During longwall mining the grout slurry is pumped into the separated beds of the rock mass through a central vertical borehole, which is drilled deep into the inter-burden rock strata above the coal seam. However, a blockage can occur in the injection system when the slurry velocity falls below a certain critical threshold velocity, indicating a material phase change from cohesive-viscous to cohesive-frictional. In situ field injection tests through boreholes have been simulated at a smaller scale at the CSIRO laboratory in Brisbane by pumping the slurry through a radial disk (gap = 4 mm) from its centre. Laboratory experiments indicate a general, nonlinear, cohesive, viscous, frictional model for shear behaviour of the slurry, in which the material shear parameters are functions of the disk radial distance. Complete dimensional and dimensionless analytical solutions have been developed based on an approach related to Bingham–Herschel–Bulkley fluid mechanics. The derived formulae include relations for minimum pump pressure, local pressure and pressure gradient, wall shear stress, volume rate, velocity and velocity gradient. The theoretical results match the experimental measurements. The experiments covered slurries with maximum particle sizes of 0.5 to 2 mm with about 50% being larger than 100 µm. The viscosities at the various solids concentrations were measured with a standard torsion viscometer. This study differs from the previous research in several distinct aspects, namely, consideration of the variable shear parameters rather than fixed values, inclusion of total nonlinear behaviour, and implementation of a friction function to mimic behaviour of the deposited and consolidating stiff slurry, which can cause a significant pressure rise as a result of the increased shear resistance.     

岩石密度和超高压岩石折返速率

在常温常压条件下对中国大陆科学钻CCSD主孔100-3000米岩心样品进行了密度测量,建立了密度连续剖面,并界定了不同超高压岩石的密度值。通过对比高温高压物性实验资料,岩石密度随着退变程度增强而降低,榴辉岩密度变化序列为3.52g/cm3→3.49g/cm3→3.07g/cm3→2.93g/cm3。超高压长英质岩石密度变化序列为3.00g/cm→2.80g/cm3→2.65g/cm3。上述实验资料是讨论不同折返阶段岩石所受浮力的基础,为研究折返速率大小提供了基本参数。本文通过折返板块运动平衡时,上浮力与粘滞力平衡这一关系式,定量研究了大陆俯冲板块的折返速率,认为密度差产生上浮力从而引起折返,温度对板块折返速率的影响最为显著;密度差大小、折返角度、折返板块大小对折返速率也有直接的影响。定量模拟分析表明,在温度高于850℃时,板块的折返速率可以超过100mm/a;当温度降至700℃时,折返速率则低于1.5mm/a。作者认为在折返早期,温度较高,板块快速折返至60-70km榴辉岩相深度;随着传导散热,温度降低,板块以较慢的速率折返至中下地壳。折返速率的估算表明,浮力是板块折返第一阶段(从>100km深部折返至<40km的中下地壳)的主要驱动力。     

Regional distribution of Al,B, Ba,Ca, K,La, Mg,Mn, Na,P, Rb,Si, Sr,Th, U and Y in terrestrial moss within a 188,000 km2 area of the central Barents region: influence of geology,seaspray and human activity

Five hundred and ninety-eight samples of terrestrial moss (Hylocomium splendens and Pleurozium schreberi) collected from a 188,000 km² area of the central Barents region (NE Norway, N Finland, NW Russia) were analysed by ICP-AES and ICP-MS. Analytical results for Al, B, Ba, Ca, K, La, Mg, Mn, Na, P, Rb, Si, Sr, Th, U and Y concentrations are reported here. Graphical methods of data analysis, such as geochemical maps, cumulative frequency diagrams, boxplots and scatterplots, are used to interpret the origin of the patterns for these elements. None of the elements reported here are emitted in significant amounts from the smelting industry on the Kola Peninsula. Despite the conventional view that moss chemistry reflects atmospheric element input, the nature of the underlying mineral substrate (regolith or bedrock) is found to have a considerable influence on moss composition for several elements. This influence of the chemistry of the mineral substrate can take place in a variety of ways. (1) It can be completely natural, reflecting the ability of higher plants to take up elements from deep soil horizons and shed them with litterfall onto the surface. (2) It can result from naturally increased soil dust input where vegetation is scarce due to harsh climatic conditions for instance. Alternatively, substrate influence can be enhanced by human activity, such as open-cast mining, creation of ‘technogenic deserts’, or handling, transport and storage of ore and ore products, all of which magnify the natural elemental flux from bedrock to ground vegetation. Seaspray is another natural process affecting moss composition in the area (Mg, Na), and this is most visible in the Norwegian part of the study area. Presence or absence of some plant species, e.g., lichens, seems to influence moss chemistry. This is shown by the low concentrations of B or K in moss on the Finnish and Norwegian side of the (fenced) border with Russia, contrasting with high concentrations on the other side (intensive reindeer husbandry west of the border has selectively depleted the lichen population).     

NEW SET OF LOW CONCENTRATION STANDARDS FOR LA, CE, SM, YB, LU, Y, SC, V, NB AND TA IN SILICATES

We have developed a set of four synthetic standards for the rare earth and high field strength elements designed for use in the determination of those elements in silicates. The base material is a glass nominally at the eutectic of the MgO-Al₂O₃-SiO₂ ternary system. The nominal doping level was 2 wt% of the elements as oxides. To avoid problems associated with peak interference, the elements were doped in four separate glasses.