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1.
岩浆侵入构造系统属地球科学复杂性理论和成矿系统理论的前沿研究。本文在总结构造岩相学填图理论和应用研究基础上,建立了岩浆侵入构造系统的构造岩相学研究内容和方法。在研究内容上从物质域-时间域-空间域,厘定构造岩相学格架、基本填图单位和独立填图单元,对岩浆侵入构造系统物质-时间-空间分布规律进行圈定。在研究层次上,遵循大地构造岩相学与成矿带构造、区域构造岩相学与矿集区构造、矿田构造岩相学与矿田构造、矿床构造岩相学与矿床构造、矿体构造岩相学与矿体构造等五个研究尺度,对岩浆侵入构造系统与成矿系统进行研究,探索岩浆侵入构造系统形成的动力学机制与金属超常富集规律。研究方法包括三维构造岩相学综合填图技术系列、构造岩相学专题研究方法和深部隐伏构造岩相学填图专题方法。以云南东川铁铜金矿集区、智利月亮山IOCG矿集区和海南丰收钨铯多金属矿床为例,论述了构造岩相学填图理论和新技术方法、岩浆侵入构造系统和找矿预测应用效果。在研究智利侏罗纪-白垩纪火山岩和侵入岩的构造岩相学特征基础上,认为白垩纪富磷灰石铁质超基性岩-铁质安山岩-铁质粗安岩等岩石组合,为IOCG成矿系统根部相和寻找IOCG矿集区的勘查标志。在月亮山IOCG矿床深部,新圈定了深部隐蔽岩浆热液角砾岩构造系统,认为电气石岩浆热液角砾岩筒为岩浆热液角砾岩构造系统中心相,赤铁矿电气石化蚀变岩属岩浆叠加热液蚀变中心相,为IOCG成矿系统的热液叠加成矿中心相标志。将云南东川和邻区新太古界-元古宙火山喷发-岩浆侵入事件序列划分为7个火山喷发-岩浆侵入旋回,建立了三大类元古宙岩浆侵入构造系统和构造岩相学分带样式,包括中元古代因民期-落雪期火山喷发-岩浆侵入构造系统、格林威尔期岩浆叠加侵入构造系统和晋宁期岩浆侵入构造系统等。通过大比例尺地面和矿山井巷工程的系列构造岩相学填图,揭示了东川铁铜金多金属矿集区内成矿系统类型的多样性,东川铁铜金多金属矿集区内成矿模型为"9层立交地铁式",探索了成矿系统深部结构,为东川铁铜金多金属矿集区深部(5000 m以浅)构造岩相学填图和找矿预测、资源高效利用和生态环境保护等提供了依据。  相似文献   

2.
地球化学岩相学及在云南个旧地区变火山岩相研究中应用   总被引:2,自引:0,他引:2  
1地球化学岩相学及研发方向地球化学岩相学可理解为:在特定的时间-空间拓扑学结构上,一组岩石类型及其它们的岩石-矿物地球化学成分,因成岩成矿系统和环境变化、物质间相互作用而发生成岩成矿作用;或不同时间序次上,不同源区和成因的成岩成矿物质在同位空间上相互叠加改造,最终形成了具有空  相似文献   

3.
含矿热液角砾岩类和非含矿角砾岩类的成岩成矿机制、独立填图单元确定和构造岩相学填图等问题,一直是困惑地质学家的难题。有效解决这些难题,对于研究和恢复矿田构造具有重要价值。在热液角砾岩成岩成矿系统中,热液角砾岩类不但是流体–岩石的多期次地球化学耦合与叠加作用、强烈流体交代作用的物理–化学反应库,也是各类叠加地质作用过程和结果的构造岩相学物质记录。因此,对其深入研究有助于提升成岩成矿系统理论认识水平。在综述以往研究基础上,本文提出了热液角砾岩构造系统概念、研究内容、研究方法和技术组合。在对角砾岩相系分类基础上,针对热液角砾岩相系的复杂性,通过岩相学填图实例解剖,总结专项填图中构造岩相学填图单元建立方法和填图技术,探索采用岩相学填图恢复热液角砾岩构造系统的新方法及技术组合。通过专项研究认为热液角砾岩系统主要形成有利的构造地质背景有:(1)复式侵入岩体在多期次岩浆侵入过程中,岩浆结晶分异和不混溶作用、岩浆冷却与围岩–先存构造多重耦合过程、同岩浆侵入期的脆韧性剪切带耦合、侵入岩体在后期构造–流体叠加过程等,对于形成热液角砾岩构造系统有利;(2)在火山岩相系中,早期次火山侵入体、晚期次火山岩侵入体和后期岩浆侵入岩体等,对于形成热液角砾岩体构造系统十分有利;(3)在沉积盆地后期叠加改造过程中,先存火山角砾岩、岩溶角砾岩和沉积角砾岩相系等,在后期盆地流体注入和多期次岩浆侵入过程中,有利于形成叠加热液角砾岩体构造系统;(4)在多期次的构造–岩浆–角砾岩杂岩带中,有利于形成热液角砾岩构造系统。研究认为多期次岩浆侵入体、火山–次火山岩侵入体和盆地中热流体是形成热液角砾岩构造系统的主要机制,包括与多期次复式侵入体有关的岩浆热液角砾岩构造系统、火山–次火山热液角砾岩构造系统、构造热液角砾岩构造系统和复合热液角砾岩系统等,它们均属矿田构造类型,也是多矿种共生矿床的成岩成矿机制。采用构造岩相学专项填图技术,对不同类型热液角砾岩构造系统及成岩成矿中心进行重建,有助于寻找和发现深部隐蔽构造和隐伏铁氧化物铜金型(IOCG)矿床找矿预测。  相似文献   

4.
开展成矿蚀变-构造岩相解析建相和建模预测研究已成为矿田构造与找矿预测的创新方向之一。文章对国内外8类重要的成矿蚀变-构造岩相模型和形成机制进行论述总结,南美洲智利科皮亚波地区IOCG型矿田受到主岛弧带-弧相关盆地及岩浆叠加-盆地变形样式的复合控制,而中国云南东川沉积岩型铜矿床(SSC型)+IOCG型铁铜矿田受陆缘裂谷盆地、盆地变形构造样式和岩浆叠加侵入构造系统的复合控制。中国内蒙古甲-查浅成低温热液型银铅锌矿田受火山洼地、火山穹隆构造、火山岩岩相类型和火山热液隐爆角砾岩的复合控制,而深成岩浆弧控制了蒙古国南戈壁斑岩型金铜钼-浅成低温热液金银矿田;中国秦岭热水沉积型(SEDEX)银铜铅锌-菱铁矿-重晶石矿田受到陆缘拉分盆地内三级热水沉积盆地、同生断裂带和热水沉积岩相的控制。大陆造山带内不同层次的脆韧性剪切带,控制了金矿田和金钼多金属矿田定位。在新疆塔西盆-山-原镶嵌区盆地系统内,侏罗系煤系烃矿源岩是金属矿田和天然气气田的成矿成藏物质供给源区;乌拉根砂砾岩型天青石-铅锌矿田受到山前挤压—伸展转换盆地、气成热流柱构造和山前冲断褶皱带的复合控制;萨热克铜多金属矿田赋存于旱地扇杂砾岩,受到对冲式...  相似文献   

5.
地球化学岩相学类型及其在沉积盆地分析中应用   总被引:1,自引:0,他引:1  
方维萱 《现代地质》2012,26(5):996-1007
按照流体地球化学动力学-岩石组合系列,地球化学岩相学相系统类型分为氧化-还原相(ORF)、酸碱相(Eh-pH F)、盐度相(SF)、温度相(TF)、压力相(PF)、化学位相(CF)、不等化学位相和不等时不等化学位地球化学岩相等8种。在沉积盆地分析中,地球化学岩相学主要用于沉积盆地物质组成及演化历史研究,恢复重建沉积盆地中流体场类型和成分特征、流体场分布范围及运移规律、流体场大规模运移机制及动力学、盆地改造过程中流体叠加关系等,进行深部找矿预测。  相似文献   

6.
方维萱 《地球科学进展》2012,27(10):1178-1184
在铁质苦橄岩—铁质安山岩、钛铁辉长岩—钛铁质闪长岩和二长岩—二长斑岩岩体附近,同岩浆侵入期脆韧性剪切带中构造岩相和热液角砾岩相,它们是铁氧化物铜金型(IOCG)矿床含矿岩相学类型。总体垂向蚀变分带为:上部为粘土化—绢云母化—赤铁矿蚀变带,中部钾质蚀变相带(电气石—铁质)+热液角砾岩化相带,下部钠质蚀变相(铁质)—热液角砾岩化带。围绕二长斑岩—二长闪长岩舌状侵入体形成电气石蚀变岩相带,属于汽成热液蚀变中心。大型—超大型IOCG矿床具有多期蚀变相系叠加特征,不同成因的热液角砾岩化相带发育、异时同位多期蚀变岩相叠加和汽成热液蚀变相发育等是寻找大型—超大型IOCG矿床标志。  相似文献   

7.
本文从矿物岩石学、地球化学和沉积盆地分析角度,研究贵州天柱大河边-湖南贡溪两个超大型重晶石矿床中重晶石(矿)岩及其共生岩石的地球化学特征及构造地质背景。天柱-新晃-玉屏寒武纪热水沉积成矿盆地是发育在大陆斜坡上的断陷型热水沉积成矿盆地,由于同生断层作用将盆地切割成一系列次级盆地,大河边-碧林及龙背-铜盆盖三级热水沉积成矿盆地是大型重晶石矿床的构造定位空间。重晶石矿层主要赋存于下寒武统牛蹄塘组第一岩性段的黑色岩系中。 重晶石矿层是由海底低温热水同生沉积作用形成(105-192℃),古热水场的地球化学类型为硫酸盐型热水。硫酸盐型热水发生大规模同生沉积成岩成矿作用形成超大型重晶石矿床,重晶石矿层之上的黑色碳质粘土岩可能形成于封闭、还原、滞流的深水沉积环境,黑色碳质粘土岩构成矿层的封闭保存条件。  相似文献   

8.
通过对金顶超大型铅锌矿床的砂岩型矿石和角砾岩型矿石较为系统的岩相学、电子探针、扫描电镜和能谱分析,初步揭示了黑色不透明物质为赋载成矿物质的主体,其本质为不均匀混溶硫化物和硅酸盐的碳酸盐熔浆快速冷凝的超显微隐晶固体,是地幔流体作用的现实微观踪迹。结合矿石矿物铅同位素组成的壳幔混染渐变特点及流体包裹体稀有气体同位素组成的壳幔混合特征进行的综合研究表明,与富碱岩浆成岩成矿背景相关的地幔流体自身携带成矿物质沿深大断裂向上运移并以交代蚀变引发壳幔混染叠加的方式参与地壳中的成矿作用,这是形成金顶超大型铅锌矿床的重要地球化学机制。  相似文献   

9.
河南省铁炉坪银矿床地球化学特征   总被引:3,自引:0,他引:3  
陈正友 《矿产与地质》2005,19(6):715-722
构造蚀变岩型银矿床在我国银矿床中占重要地位.通过对矿床成矿环境、地球化学背景、矿床主要赋矿地层、蚀变、矿体中微量元素空间分布和矿区的水系沉积物、土壤、岩石地球化学异常特征等方面的研究,阐述了铁炉坪银矿床的成矿机理、元素分带,并建立了该类型矿床地质-地球化学找矿模型.为该区银矿找矿奠定基础.  相似文献   

10.
探讨和总结了扬子地块西缘大地构造演化、元古宙重大构造-岩浆事件与铁氧化物铜金型(IOCG)矿床关系,以促进对深部隐伏IOCG矿床勘查和新技术研发。在新太古界-古元古界小溜口岩组顶部和不整合面之下,含矿层状-似层状碱性方解石钠长石岩中锆石SHRIMP U-Pb年龄为2520±14 Ma,这种似层状铜矿床和其上不整合面型Cu-Co-AuAg-REE-Fe矿体,以云南东川因民铁铜矿床深部小溜口岩组中铜矿床为代表。总体上,IOCG矿床与扬子地块大地构造演化之间关系为:(1)扬子地块于东川运动(中条运动/Hudsonian Orogeny,1800 Ma)形成了陆壳基底。在中元古代初期(1700±50 Ma)发生了地幔热物质上涌侵位的构造-岩浆事件,导致古扬子地块发生裂解并形成裂谷构造和大陆裂谷盆地。在近东西向大陆裂谷盆地发育初期,构造动力学特征为火山地堑式断陷成盆。在碱性铁钠质基性岩、铁钾质粗面岩和铁质辉绿辉长岩形成过程中,形成了第一期IOCG矿床成岩成矿高峰期(1650±50 Ma),以云南大红山IOCG矿床为代表。(2)在裂谷盆地成熟发育期,构造动力学特征为裂陷沉降成盆。因民期和黑山期两次地幔热物质上涌侵位,导致了构造-岩浆-成岩成矿事件发生。在铁钠质基性火山岩、铁钾质粗面岩、水下火成碳酸岩、火山喷溢-火山热水喷流沉积相等形成过程中,形成了第二期IOCG矿床的成岩成矿高峰期(1500±50 Ma),以云南迤纳厂IOCG矿床为代表。(3)在小黑箐运动/满银沟运动(格林威尔造山期,1000 Ma±),扬子地块南缘形成了近南北向洋壳俯冲和陆缘侧向挤压收缩体制,碱性铁质辉长岩-辉绿岩体上涌侵位,伴随同构造期脆韧性剪切带形成和沉积盆地构造反转,形成区域性不整合面(小黑箐运动/满银沟运动)和后期沉积型-火山沉积型铁矿床,为IOCG矿床第三期成岩成矿高峰期(1000±100 Ma)。以白锡腊深部和新塘IOCG矿床为代表,形成IOCG矿床和IOCG矿床的叠加成岩成矿。(4)晋宁-澄江期为多重构造体制耦合与转换格局,扬子地块内部和陆缘具有造山带-沉积盆地-深部地幔柱上涌侵位,深部地幔柱上涌侵位形成的碱性铁质辉长岩具有OIB源区特征,形成了第四期IOCG矿床的成岩成矿高峰期(800±50 Ma),以四川拉拉IOCG矿床受碱性铁质辉长岩侵位与叠加成岩成矿为代表。在澄江期"盆→山"耦合与转换,IOCG矿床和东川型铜矿中进一步发生了盆地流体叠加改造富集(810~700 Ma)。  相似文献   

11.
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.  相似文献   

12.
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  相似文献   

13.
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.  相似文献   

14.
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。  相似文献   

15.
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。  相似文献   

16.
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.  相似文献   

17.
18.
岩石密度和超高压岩石折返速率   总被引:1,自引:3,他引:1  
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。  相似文献   

19.
《Applied Geochemistry》2001,16(2):137-159
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).  相似文献   

20.
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.  相似文献   

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