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1.
土屋斑岩铜矿位于大南湖晚古生代岛弧带中段,矿体主要赋存于闪长玢岩中。闪长玢岩为钠质亚碱性系列:w(SiO2)51.56%~56.98%;w(Al2O3)16.41%~19.17%;w(Na2O)2.6%~5.42%;w(K2O)0.582%~2.24%;全碱w(Na2O+K2O)3.182%~6.205%;w(K2O)/w(Na2O)为0.144~0.78。微量元素蛛网图右倾,大离子亲石元素富集,高场强元素相对亏损,Nb、Ta负异常明显。稀土总量较低,ΣREE为34.06×10-6~96.02×10-6,轻稀土富集,LREE/HREE为3.40~5.98,δEu为0.65~1.10,没有发生明显的斜长石结晶分异作用;δCe为0.90~0.99,表明氧化条件弱。根据闪长玢岩地球化学、U-Pb年代学及构造环境图解分析,显示闪长玢岩体形成于哈萨克斯坦-准噶尔板块活动陆缘。  相似文献   

2.
石炭系企鹅山群第二组火山-沉积岩是土屋铜矿的围岩,岩性以玄武岩为主。玄武岩为钠质亚碱性玄武岩;w(SiO2)为50.65%~54.13%;w(Al2O3)为16.48%~18.89%;w(Na2O)为2.02%~3.9%;w(K2O)为0.098%~1.76%;全碱w(Na2O+K2O)为2.118%~5.21%。微量元素蛛网图右倾,大离子亲石元素富集,高场强元素相对亏损,Nb-Ta负异常明显。稀土总量较低,ΣREE 50.64×10-6~117.73×10-6,轻稀土富集,轻重稀土分馏不明显,LREE/HREE为3.40~7.15,Eu为0.98~1.14,没有发生明显的斜长石结晶分异作用,δCe为0.94~0.99,氧化条件弱。玄武岩主量元素、微量元素、稀土元素结合构造环境图解分析显示企鹅山群第二组火山-沉积岩形成于岛弧环境。  相似文献   

3.
砂子塘铝土矿床以Al_2O_3含量高、A/S值高为特征,是滇东南地区少有高品质铝土矿床。笔者以砂子塘铝土矿床沉积型铝土矿为研究对象,研究了该矿床沉积型铝土矿的地球化学特征,进而对其成矿物质来源、成矿环境进行了讨论。含铝岩系的稀土总量总体较高,具中等程度的Eu负异常,具Ce正异常和Ce负异常;稀土配分曲线均为向右倾斜的弱"V"字型曲线,斜率不等,反映稀土元素分馏程度不等。含铝岩系明显富集大离子亲石元素U、高场强元素Nb、Ta、Zr、Hf、Th和亲铁元素Cr,其余元素则明显亏损。含铝岩系之中伴生有黑色金属Ti、稀土元素、分散元素Ga、稀有金属Nb和Li,可以与Al_2O_3一起综合利用。聚类分析显示,Al_2O_3与Nb、TiO_2、REE呈正相关,而与Ga、Fe_2O_3、Li呈负相关。含铝岩系灰岩标准化曲线为近水平的"U"字型曲线,含铝岩系的钛率(16.89)与下伏威宁组灰岩的钛率(13.09)接近,说明含铝岩系与下伏的威宁组灰岩关系密切。含铝岩系的Be含量低(3.60×10~(-6)),Th/U较高(6.07),多具Ce负异常,说明砂子塘铝土矿床来源于风化壳,后又经历了沉积作用的改造;Ga含量高(25.25×10~(-6)),Sr含量低(77.7×10~(-6)),Ba含量低(34.4×10~(-6)),V/Zr值较低(0.22),Eu/Sm值较低(0.21),显示出陆相沉积的特征;Sr/Ba值高(3.28),显示出海相沉积的特征。这预示着砂子塘铝土矿床的成矿物质来源于古风化壳,沉积作用改造不明显。  相似文献   

4.
黔北浣溪铝土矿床为产于石炭系黄龙组灰岩古侵蚀风化面或志留系韩家店组黏土岩、页岩、砂岩等侵蚀间断面之上的一水硬铝石沉积型大型铝土矿床,初步探明铝土矿资源量2000×104余吨。研究表明,浣溪铝土矿床地表矿体质量总体优于深部,地表矿体具有中铁、低硫特征,深部矿体具有中铁、高硫特征。矿石主要化学组分为Al2O3、SiO2、Fe2O3、TiO2及烧失量,占矿石组分的95%~98%,Al2O3与SiO2呈负相关关系;镓、锂是矿床的伴生有益元素。矿床的形成主要受地层岩性、向斜构造、古气候、古沉积环境等因素控制;炎热潮湿的古气候条件和半封闭海湾环境利于成矿。  相似文献   

5.
贵州新民铝土矿矿床Li的地球化学特征与富集机制探究   总被引:2,自引:2,他引:0  
龙珍  付勇  何伟  唐波  龙克树  刘阳  王天顺 《矿床地质》2021,40(4):873-889
新民铝土矿床位于黔北务川-正安-道真地区(简称务正道地区)大塘向斜东翼,铝土矿(岩)型Li资源丰富.含矿岩系大竹园组(P1d)不同岩性的w(Li)有差别:土状-半土状铝土矿平均w(Li)为16.34×10-6,致密块状铝土矿平均w(Li)是803.84×10-6,铝土岩平均w(Li)是1436.22×10-6,黏土岩的平均w(Li)是786.62×10-6,梁山组泥岩的平均w(Li)是51.82×10-,韩家店群泥岩(页岩)的平均w(Li)是48.52×10-6,黄龙组灰岩的平均w(Li)是 11.99×10-6.由此可知,研究区铝土矿(岩)型Li资源主要富集在含矿岩系中上部的致密块状铝土矿、铝土岩和黏土岩中,顶板、底板以及土状-半土状铝土矿w(Li)较低.Li主要赋存于高岭石中,伊利石(水云母)和残存的三水铝石、勃姆石也可富集少量Li,当样品中赋锂矿物(高岭石、伊利石(水云母)、三水铝石和勃姆石)都存在时,高w(Li),主量元素w(Al3O2)、w(SiO2)、w(MgO)、w(K2O)、w(TiO2)和w(TFe2O3)与w(Li)的相关性也证实了上述结果.研究区的地球化学比值 CIA、w(Sr)/w(Cu)、u(CaO)/w(MgO)、w(Sr)/w(Ba)、w(V)/w(V+Ni)和 w(La)/w(Y)综合显示,炎热潮湿的古气候下,有机质腐烂形成酸性环境,半封闭海湾环境下,黏土化阶段中等强烈的化学风化程度和适宜的风化暴露剥蚀时间利于铝硅酸盐矿物和硅酸盐矿物化学键断裂,富集Al3+形成高岭石;风化程度过于强烈和长时间的风化剥蚀,继续脱Si富Al形成以硬水铝石为主的铝土矿;弱酸性-弱碱性以及氧化-还原过渡条件下,使得高岭石能最大程度的吸附Li元素.  相似文献   

6.
龙珍  付勇  何伟  唐波  龙克树  刘阳  王天顺 《矿床地质》2021,40(4):873-890
新民铝土矿床位于黔北务川-正安-道真地区(简称务正道地区)大塘向斜东翼,铝土矿(岩)型Li资源丰富.含矿岩系大竹园组(P1d)不同岩性的w(Li)有差别:土状-半土状铝土矿平均w(Li)为16.34×10-6,致密块状铝土矿平均w(Li)是803.84×10-6,铝土岩平均w(Li)是1436.22×10-6,黏土岩的平均w(Li)是786.62×10-6,梁山组泥岩的平均w(Li)是51.82×10-,韩家店群泥岩(页岩)的平均w(Li)是48.52×10-6,黄龙组灰岩的平均w(Li)是 11.99×10-6.由此可知,研究区铝土矿(岩)型Li资源主要富集在含矿岩系中上部的致密块状铝土矿、铝土岩和黏土岩中,顶板、底板以及土状-半土状铝土矿w(Li)较低.Li主要赋存于高岭石中,伊利石(水云母)和残存的三水铝石、勃姆石也可富集少量Li,当样品中赋锂矿物(高岭石、伊利石(水云母)、三水铝石和勃姆石)都存在时,高w(Li),主量元素w(Al3O2)、w(SiO2)、w(MgO)、w(K2O)、w(TiO2)和w(TFe2O3)与w(Li)的相关性也证实了上述结果.研究区的地球化学比值 CIA、w(Sr)/w(Cu)、u(CaO)/w(MgO)、w(Sr)/w(Ba)、w(V)/w(V+Ni)和 w(La)/w(Y)综合显示,炎热潮湿的古气候下,有机质腐烂形成酸性环境,半封闭海湾环境下,黏土化阶段中等强烈的化学风化程度和适宜的风化暴露剥蚀时间利于铝硅酸盐矿物和硅酸盐矿物化学键断裂,富集Al3+形成高岭石;风化程度过于强烈和长时间的风化剥蚀,继续脱Si富Al形成以硬水铝石为主的铝土矿;弱酸性-弱碱性以及氧化-还原过渡条件下,使得高岭石能最大程度的吸附Li元素.  相似文献   

7.
贵州务正道地区铝土矿床稀土元素组成及地质意义   总被引:2,自引:0,他引:2  
稀土元素(REE)是一组具有相同地球化学性质和特殊地球化学属性的指示性元素。务正道地区主要矿床稀土元素组成显示出,矿层和下伏志留系韩家店组地层稀土元素总量、配分模式基本一致,相关性较好,揭示铝土矿成矿物源与下伏志留系韩家店组有成因联系;矿层和韩家店组LREE/HREE均大于1,轻稀土富集较强烈,而重稀土不同程度亏损;(La/Ce)N平均0.87,总体较低;δCe平均1.22,为弱-中等比值,表明铝土矿物源主要来自陆源,沉积环境主要为陆相沉积,局部为海相沉积;主要层位(La/Sm)N>(Gd/Yb)N,说明轻重稀土元素分异较好;稀土元素富集对岩性有选择性,在矿层及富含绿泥岩、粉砂质页岩的志留系韩家店组地层中强烈富集,在石炭系黄龙组白云质灰岩及二叠系栖霞组灰岩中贫化。  相似文献   

8.
务正道地区是中国重要的铝土矿区,本文对该区各类矿石、赋矿围岩及基底层(韩家店组S1-2hj)进行主、微量及稳定同位素研究。结果表明,基底层中Al2O3含量低于赋矿围岩及矿体,但明显高于其他地层,从基底层→赋矿围岩→豆鲕状、碎屑状铝土矿→土状铝土矿,Al2O3、Ti O2、K2O含量升高,Si O2含量降低;Rb、Ba、Sr、Cs、Ni等表现为亏损,Li、Be、V、Cr及高场强元素Nb、Ta、Zr、Hf、Th、U等主要表现为富集。各类矿石、赋矿围岩与基底层稀土配分型式相似,均为LREE富集、δEu1、δCe1;δ34S为-29.2‰~19.35‰,分布范围较广,具多样性,含海水硫、生物硫及幔源硫。结合成矿背景、地质地球化学特征等,认为该区铝土矿成矿物质直接来源为基底层韩家店组,最终来源为上地壳硅酸盐岩类物质,矿床成因类型主要为风化-沉积型,成矿环境主要为滨浅海-潟湖(海陆交互)环境。  相似文献   

9.
通过对黔北新民铝土矿岩矿石稀土元素的系统分析,探讨了黔北铝土矿稀土元素特征与富集机制。研究发现:黄龙组灰岩呈"平坦型"稀土元素配分模式,韩家店群泥岩、梁山组炭质泥岩及大竹园组(含矿岩系)呈"右倾型"轻稀土富集特征,而大竹园组随着风化作用的增强从陡"右倾型"的铝质泥岩→缓"右倾型"的豆状、致密块状、碎屑状铝土矿→缓"左倾型"土状铝土矿的特征。且含矿岩系由底到顶,∑REE具减少趋势,顺着其倾向∑REE有下降趋势,沿着走向其有升高趋势;这受到不同底板岩性及厚度大小的影响,底板泥岩比灰岩更易使含矿岩系富集稀土,同为灰岩,其厚度越大其稀土总量有富集趋势。而∑REE受到矿物组合(岩性)控制,其有"含独高稀,鲕粒富稀,豆状少稀,高铝贫稀"特征。对实验数据进行分析和做相关性图解(Sr/Ba—∑REE、Sr/Cu—∑REE、δCe—∑REE、δEu—∑REE)可知,在干热气候的海相咸水环境更易使稀土富集,虽含矿岩系主要是在氧化环境中形成,但高∑REE样品易在还原环境中富集。  相似文献   

10.
运用岩相学研究理论和元素地球化学研究理论,针对冀北赤城二堡子片麻状角闪二长岩,进行岩相学(4件样品)和地球化学分析(4件样品),结果表明:角闪二长岩的矿物成分为斜长石(30%~35%)、碱性长石(25%~30%)、角闪石(15%~20%)、石英(10%~15%)和黑云母(5%~10%)等。岩石中w(SiO2)介于60.16%~62.16%之间,w(K2O+Na2O)为8.56%~8.82%,稀土总量较高(ΣREE为246.30×10-6~317.76×10-6),(La/Yb)N值为28.18~42.79,具有轻稀土富集、重稀土亏损的分配模式,Eu异常(Eu/Eu*值为0.90~1.03)及Ce异常(Ce/Ce*值为0.91~0.98)均不明显,富集大离子亲石元素(如Ba,Rb,Sr和Th等)及轻稀土元素(如La,Ce和Nd等),亏损高场强元素(如Nb,Ta,Zr和Hf等)。角闪二长岩的锆石SIMS U-Pb年龄为243.1Ma±1.8 Ma,锆石的Th/U比值为0.709~1.258,表明其形成于三叠纪,应该是中生代印支期岩浆作用的产物,这是赤城地区确定的第二个印支期中酸性侵入岩体,其形成可能与赤城-崇礼断裂带在印支期重新活动有关。赤城印支期角闪二长岩体的确定表明赤城、崇礼地区存在印支期(~239Ma^243Ma)岩浆-变质-构造热事件,这对于冀北大地构造演化特征的确定具有重要的指示意义。  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   

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Between 1985 and 1991, two new mountain protected areas (MTNPA) covering more than 35,000 km2 and based on participatory management models — the Makalu-Barun National Park and Conservation Area, Nepal, and Qomolangma Nature Preserve, Tibet Autonomous Region — were successfully established through the collaborative efforts of Woodlands Mountain Institute and conservationists in China and Nepal. Characteristics common to both projects include the importance of establishing (1) effective rationales, (2) local support constituencies, (3) a senior advisory group, (4) a task force, (5) linkages between conservation and development, and (6) fund raising mechanisms. The lessons derived from the experiences of Woodlands Mountain Institute are of significant value to others in preserving MTNPA. Increased collaboration and communication between all interested in conservation, however, will remain a critical component for expanding mountain protected area coverage to throughout the world.  相似文献   

19.
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   

20.
《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   

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