首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 140 毫秒
1.
本文通过锆石LA-ICP-MS U-Pb定年法对云南格咱岛弧中部的地苏嘎成矿斑岩体中不含矿石英闪长玢岩和含矿两类石英闪长玢岩进行了年代学研究,获得了不含矿石英闪长玢岩(DSG-1)的形成年龄为203.03±0.54Ma,含矿石英闪长玢岩(DSG-2)的年龄分为两组217.25±0.89Ma和208.5±1.0Ma,限定了地苏嘎岩体的岩浆活动时限为217~203Ma,表明与成矿作用相关的热事件主要发生在208Ma。地苏嘎石英闪长玢岩的地球化学特征表明岩石具岛弧岩浆岩的特征,岩石富钠(Na2O/K2O=0.91~2.91,平均为1.65),准铝质(A/CNK=0.848~1.244,平均0.996),岩石富集轻稀土元素(LREE),La N/Yb N为9.44~26.09,富集大离子亲石元素(LILE,K、Rb、Ba、Sr)和不相容元素(U、Th、Pb),亏损高场强元素(HFSE,Nb、Hf、P、Ti)。地苏嘎成矿岩体的成岩成矿时代均发生在印支晚期,区域构造演化和岩石地球化学特征反映岩体形成于岛弧构造环境,其形成与格咱岛弧印支期洋壳的俯冲作用密切相关。岩浆作用和成矿作用基本吻合,但岩浆作用的时限已接近燕山早期,说明云南格咱岛弧也存在燕山早期的岩浆活动,这对探讨格咱岛弧构造岩浆演化及成岩成矿作用的研究具有重要意义。  相似文献   

2.
本文通过锆石LA ICP MS U Pb定年法对云南格咱岛弧中部的地苏嘎成矿斑岩体中不含矿石英闪长玢岩和含矿两类石英闪长玢岩进行了年代学研究,获得了不含矿石英闪长玢岩(DSG 1)的形成年龄为20303±054Ma,含矿石英闪长玢岩(DSG 2)的年龄分为两组21725±089Ma和2085±10Ma,限定了地苏嘎岩体的岩浆活动时限为217~203Ma,表明与成矿作用相关的热事件主要发生在208Ma。地苏嘎石英闪长玢岩的地球化学特征表明岩石具岛弧岩浆岩的特征,岩石富钠(Na2O/K2O=091~291,平均为165),准铝质(A/CNK=0848~1244,平均0996),岩石富集轻稀土元素(LREE),LaN/YbN为944~2609,富集大离子亲石元素(LILE,K、Rb、Ba、Sr)和不相容元素(U、Th、Pb), 亏损高场强元素(HFSE,Nb、Hf、P、Ti)。地苏嘎成矿岩体的成岩成矿时代均发生在印支晚期,区域构造演化和岩石地球化学特征反映岩体形成于岛弧构造环境,其形成与格咱岛弧印支期洋壳的俯冲作用密切相关。岩浆作用和成矿作用基本吻合,但岩浆作用的时限已接近燕山早期,说明云南格咱岛弧也存在燕山早期的岩浆活动,这对探讨格咱岛弧构造岩浆演化及成岩成矿作用的研究具有重要意义。  相似文献   

3.
滇西北中甸松诺含旷斑岩的锆石SHRIMP U-Pb年龄及地质意义   总被引:8,自引:1,他引:7  
位于义敦岛弧南端的中甸岛弧中广泛发育印支期斑岩及斑岩型和矽卡岩型铜矿床.松诺(或称松诺力赞)复式岩体位于东斑岩带中部,由石英闪长玢岩、黑云石英二长斑岩、闪长玢岩和含矿石英二长斑岩组成,其南部为普朗超大型斑岩铜矿床,北部为地苏嘎铜矿点.本文对含矿石英二长斑岩进行了岩相学和锆石SHRIMP U-Pb 定年研究,结果表明所有锆石颗粒自形较好且均发育规则的韵律环带,Th 含量为 180~854 μg/g,U 含量为270~709μg/g,Th/U 比值为 0.77~1.24,为典型岩浆成因锆石.获得了含矿石英二长斑岩的侵位年龄为220.9±3.5Ma(n=9,MSWD= 1.6),这与中甸岛弧洋壳俯冲造山作用的时限(210~235 Ma)相吻合.  相似文献   

4.
滇西北中旬松诺含矿斑岩的锆石SHRIMP U-Pb年龄及地质意义   总被引:3,自引:1,他引:2  
位于义敦岛弧南端的中甸岛弧中广泛发育印支期斑岩及斑岩型和矽卡岩型铜矿床.松诺(或称松诺力赞)复式岩体位于东斑岩带中部,由石英闪长玢岩、黑云石英二长斑岩、闪长玢岩和含矿石英二长斑岩组成,其南部为普朗超大型斑岩铜矿床,北部为地苏嘎铜矿点.本文对含矿石英二长斑岩进行了岩相学和锆石SHRIMP U-Pb 定年研究,结果表明所有锆石颗粒自形较好且均发育规则的韵律环带,Th 含量为 180~854 μg/g,U 含量为270~709μg/g,Th/U 比值为 0.77~1.24,为典型岩浆成因锆石.获得了含矿石英二长斑岩的侵位年龄为220.9±3.5Ma(n=9,MSWD= 1.6),这与中甸岛弧洋壳俯冲造山作用的时限(210~235 Ma)相吻合.  相似文献   

5.
滇西北中甸松诺含矿斑岩的锆石SHRIMP U-Pb年龄及地质意义   总被引:9,自引:1,他引:8  
位于义敦岛弧南端的中甸岛弧中广泛发育印支期斑岩及斑岩型和矽卡岩型铜矿床。松诺(或称松诺力赞)复式岩体位于东斑岩带中部,由石英闪长玢岩、黑云石英二长斑岩、闪长玢岩和含矿石英二长斑岩组成,其南部为普朗超大型斑岩铜矿床,北部为地苏嘎铜矿点。本文对含矿石英二长斑岩进行了岩相学和锆石SHRIMPU-Pb定年研究,结果表明所有锆石颗粒自形较好且均发育规则的韵律环带,Th含量为180~854μg/g,U含量为270~709μg/g,Th/U比值为0.77~1.24,为典型岩浆成因锆石。获得了含矿石英二长斑岩的侵位年龄为220.9±3.5Ma(n=9,MSWD=1.6),这与中甸岛弧洋壳俯冲造山作用的时限(210~235Ma)相吻合。  相似文献   

6.
欠虽铜矿床位于西南三江地区义敦岛弧南段的格咱岛弧中南部,是近年来该区新发现的铜多金属矿床,具有良好的找矿前景。目前该地区已发现若干印支期成矿事件中形成的中大型矿床,是中国重要的多金属矿集区。本文通过LA-ICP-MS锆石U-Pb定年方法对欠虽铜矿石英闪长玢岩进行了年代学研究,获得铜矿化石英闪长玢岩的形成年龄为(220.3±0.66)Ma(MSWD=0.99)。岩石地球化学特征研究表明,欠虽石英闪长玢岩具有富钠(K2O/Na2O为0.05~1.42,平均值为0.86)、准铝质(0.82~1.19,平均值为1.07)的特征,岩石富集轻稀土元素(LREE),轻重稀土元素分馏明显(LaN/YbN=19.6~28.8),富集大离子亲石元素(LILE,Ba、Th、U、Sr),亏损高场强元素(HFSF,Ta、Nb、Ce、P、Ti),属于典型的I型花岗岩。欠虽铜矿成矿岩体成岩时代发生在印支晚期,含矿斑岩的微量元素特征、构造背景及同位素特征反映欠虽岩体形成于岛弧环境,与格咱岛弧印支期洋壳的俯冲造山作用密切联系。通过地球化学特征及成岩成矿年代的研究,表明欠虽多金属矿的形成年限与甘孜—理塘洋壳俯冲造山作用时限相近,且与普朗铜矿、红山铜矿是同期次同源构造-岩浆演化的产物,这对探讨格咱岛弧构造-岩浆演化及成岩成矿作用的研究具有重要意义。  相似文献   

7.
宁芜盆地闪长玢岩的形成时代及对成矿的指示意义   总被引:40,自引:24,他引:16  
范裕  周涛发  袁峰  张乐骏  钱兵  马良 《岩石学报》2010,26(9):2715-2728
宁芜盆地是长江中下游成矿带的重要组成部分和玢岩型铁矿床的主要产地,盆地内广泛产出闪长玢岩,这类岩体与铁矿床的形成关系密切,但其精确的成岩成矿时代及其形成构造背景的研究仍十分薄弱。本次工作在详细野外地质工作的基础上,系统开展了盆地内与铁矿床有关的7个闪长玢岩体的年代学研究,通过对闪长玢岩锆石LA-ICP-MS同位素定年方法,确定了盆地内主要闪长玢岩体,凹山岩体、陶村岩体、和尚桥岩体、东山岩体、白象山岩体、和睦山岩体和姑山岩体的成岩时代分别为130.2±2.0Ma、130.7±1.8Ma、131.1±1.5Ma、131.1±3.1Ma、130.0±1.4Ma、131.1±1.9Ma和129.2±1.7Ma。定年结果表明盆地内闪长玢岩成岩年龄均为130Ma左右,其成岩年龄可以近似代表铁矿床的成矿年龄。长江中下游地区存在145~136Ma、135~127Ma、126~123Ma三期成岩(成矿)作用,宁芜盆地内闪长玢岩是第二期岩浆活动的产物,其形成时代明显晚于长江中下游成矿带断隆区内与斑岩型-矽卡岩型铜(铁)、金矿床有关的高钾钙碱性岩体。宁芜盆地内闪长玢岩及玢岩型铁矿床形成于区域岩石圈伸展构造环境。  相似文献   

8.
张达玉  周涛发  袁峰  范裕  刘帅  彭明兴 《岩石学报》2010,26(11):3327-3338
延西铜矿床位于新疆东天山觉罗塔格地区北部的哈尔里克-大南湖岛弧带内,是延东-土屋斑岩型成矿带的西延部分。矿床的赋矿地层主要为石炭系企鹅山群,被含矿斜长花岗斑岩侵入。矿床中的主要岩石类型为安山岩、闪长玢岩以及斜长花岗斑岩,安山岩和闪长玢岩具有同源性及岛弧火山岩的特点,是主要的赋矿围岩;斜长花岗斑岩具有埃达克质岩石的特征,与成矿作用直接相关,其形成晚于安山岩、闪长玢岩。本文测得延西铜矿床辉钼矿Re-Os年龄为326.2±4.5Ma,可以代表其成矿年龄,与土屋-延东铜矿床322.7±2.3Ma的辉钼矿Re-Os年龄基本相同;包括延西铜矿床在内的土屋-延东斑岩型铜矿带成矿时代与成岩时代基本一致或稍晚。延西铜矿床具有斑岩型铜矿床的矿化和围岩蚀变特征,与土屋-延东斑岩型铜矿带内其它矿床均为中石炭世同源岩浆演化的产物,具有相似的成矿作用过程,成矿物质均为岩浆来源,这些矿床可能为同一岩浆活动在不同部位发生矿化的产物。延西铜矿床以及土屋-延东斑岩型铜矿带形成于东天山觉罗塔格地区晚古生代的挤压岛弧背景,应与哈尔里克-大南湖晚古生代岛弧的形成相伴,可能与康古尔塔格大洋板块向北部哈尔里克-大南湖岛弧的俯冲有关。  相似文献   

9.
雄村超大型铜金矿床的主要成矿作用发生在具眼球状石英斑晶的石英闪长玢岩及其外接触带强蚀变中细粒凝灰岩中,由产于斑岩体内的细脉浸染型矿体和产于凝灰岩中的细脉浸染型矿体、脉状矿体组成.文章在对含矿岩系及其侵位于含矿岩系的浅成岩和穿切矿体的花岗闪长岩等地质体进行详细的地质填图基础上,对雄村Ⅰ号、Ⅱ号矿体含矿围岩(暂定为雄村组J1-2x)、最早侵位的浅成岩-角闪石英闪长玢岩(J2δομ1)、含矿斑岩--具眼球状角闪石英闪长玢岩(J2δομ)、穿插矿体的黑云母花岗闪长岩(E2γδβ)(谢通门大岩基的一部分)、Ⅱ号矿体矿石中的辉钼矿等,开展了系统的成岩成矿年代学研究.锆石的U-Pb同位素测年结果表明,含矿围岩凝灰岩加权平均年龄为(176±5)Ma(MSWD=0.63;n=9);与成矿有关的含眼球状石英斑晶的石英闪长玢岩加权平均年龄为(173±3)Ma(MSWD=1.16;n=16);穿插侵吞矿体的谢通门大岩基花岗闪长斑岩加权平均年龄为(46.5±1.1)Ma(MSWD=0.83;n=14);所有锆石均显示岩浆成因锆石的特点.锆石U-Pb同位素研究显示含矿围岩形成于早中侏罗世,偏中性的含矿岩体侵位于中侏罗世,而侵吞穿插矿体的大岩基形成时代为始新世.雄村铜金矿Ⅱ号矿体4件辉钼矿样品的Re-Os同位素测定结果显示,辉钼矿w(187Re)为1 269~1 354μg/g,w(187Os)为3 587~3 993 ng/g.辉钼矿的模式年龄为169.5~176.8 Ma,平均模式年龄为(173.2±4.7)Ma(MSWD=5.6),显示成矿年龄为中侏罗世早期.结合多个岩体和岩脉的Ar-Ar同位素年龄测定结果和其他研究者的成果,认为雄村铜金矿属于岛弧型斑岩铜金矿床,由新特提斯洋的早期俯冲所致.雄村岛弧型斑岩铜金矿的发现和勘探、外围找矿的突破及本次系统年代学研究,提供了特提斯洋俯冲阶段成矿的信息,拓宽了西藏冈底斯成矿带新的找矿方向.  相似文献   

10.
德兴斑岩铜矿是我国东部最大的斑岩型铜矿,但其成矿时限的研究较为薄弱。为进一步确定德兴斑岩铜矿成矿的持续时间,系统采集了矿田内朱砂红矿区成矿期后石英闪长玢岩脉岩样品进行锆石U-Pb年代学和岩石地球化学研究。结果表明,朱砂红石英闪长玢岩具有高场强元素亏损的弧岩浆特征,指示其岩浆源区可能有俯冲改造的岩石圈地幔物质的加入。前人研究获得的德兴斑岩铜矿成矿岩体的年龄为170 Ma,本次研究获得的1个样品中锆石的25个分析点的~(206)Pb/~(238)U的加权平均年龄为(166±1)Ma(MSWD=0.13),两者共同限制了德兴斑岩铜矿的成矿时限不超过4 Ma。中侏罗世,伊泽纳崎板块开始向华南大陆俯冲,在华南内陆产生一系列伸展型岩浆作用,朱砂红石英闪长玢岩脉应形成于陆内的局部拉伸构造背景。  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.
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   

13.
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   

14.
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   

15.
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   

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.
Bellechester, Minnesota, is a small community of approximately 155 residents located on the county line between Goodhue and Wabasha counties in southeast Minnesota's karst region. Bellechester is served by a 21-year-old wastewater treatment facility (WWTF) consisting of three waste-stabilization ponds. On 28 April 1992 six sinkholes were discovered to have drained cell 2 of the WWTF resulting in the loss of approximately 8.7×106 1 of partially treated effluent and about 600 m3 of soil into previously undetected subsurface voids of unknown dimensions. In the week following the collapse, approximately 200 water wells located within a 5-km radius of the WWTF were sampled in an after-the-fact, emergency sampling program. Twelve samples with elevated fecal coliform levels, 18 samples with nitrate-nitrogen greater than the 10 mg/1 standard, and no samples with elevated chlorides were found. However, the elevated levels could not be unambiguously attributed to the WWTF collapse. This is the third WWTF to fail by sinkhole collapse in southeast Minnesota since 1974. All three collapsed lagoons have been located in similar geomorphic and stratigraphic settings. However, at least two lagoons have collapsed in the adjacent area in northeast Iowa, and these lagoons are located at different stratigraphic positions. Twenty-two WWTFs constructed in southeast Minnesota's karst region in the last 25 years have been identified as subject to potential sinkhole collapse. An unknown but significant number of manure storage lagoons, flood control structures, etc., have also been constructed in the karst region and are at risk. Public agencies are beginning to develop plans to deal with the risk associated with existing and future waste lagoons in this environment. The critical hydrogeologic parameters that can be used to prioritize the risk of collapse at existing facilities include: (1) the lithology of the first bedrock beneath each lagoon, (2) the thickness of surficial materials between the lagoon and the bedrock surface, (3) the presence and construction of liners (seepage rate), and (4) the proximity to existing sinkholes.  相似文献   

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.
20.
滇东南锡、银、铅、锌多金属矿床主要分布在个旧、白牛厂、都龙3个矿区,而滇东南较大的3个花岗岩体又分别出露在3个矿区或附近.花岗岩体均形成于燕山晚期,岩石化学、矿物成分相似,富含锡、银、铅、锌、钨、铜等成矿元素.矿床主金属元素组合与岩体之间的距离由远而近出现由锡、钨、(铍、铌、钽)→锡、钨、(铁)、铜、铟→锡、铅、锌、银、铟、(锑)有规律的变化.花岗岩浆是成矿物质来源和成矿热源.岩浆侵入初期使上覆地层隆起产生背斜(凹陷部位成向斜);同时使地层产生一系列裂隙、压性断层或层间断裂;岩浆侵入晚期,这些断层再次活动,表现为张性,岩浆产生的含矿热液沿由其活动所造成的断裂迁移、充填、交代、沉淀而形成矿床.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号