临沧超大型锗矿床的沉积环境、成岩过程和热液作用与锗的富集

临沧超大型锗矿庆的形成与其沉积、成岩和热液作用有密切联系。详细研究了矿床煤岩产出特征、煤岩组成、无机矿物、微量元素、腐殖体反射率,认为该矿床中的锗主要源于盆地西缘的白云母花岗岩的风化作用。在沉积作用阶段,锗被湖水中的低等生物和腐殖酸富集,为形成矿化煤打下基础。临沧褐煤经历了泥炭化阶段、早期成岩阶段和热液改造阶段。泥炭化阶段,沉积物中锗被凝胶体吸附和配合。早期成岩阶段,与腐残酸结合的锗,在碱性还原条     

Ore potentiality of the Vanchin Graben, Primorye, Russia

New data on Cenozoic mineralization in the Vanchin coal basin are presented. In addition to the Au-Ag quartz-adularia veins known since the 1970s (Soyuzny deposit), stratified Au-Ag mineralization in tuffaceous-sedimentary rocks, porphyry tin mineralization in the extrusion of tourmalinized rhyolite, metalliferous coal seams enriched in Au, Ge, and REE are hosted in this graben. The localization and chemical and mineral compositions of these types of mineralization are considered. It is shown that Au-Ag mineralization is more widespread in the graben that was previously supposed. The anomalous and diverse mineralization of the Vanchin Graben is attributed, first of all, to long-term evolution of volcanism and hydrothermal activity developing synchronously with lacustrine and bog sedimentation and continuing after its termination. The main stages of ore formation are related to volcanic centers differing in age and conjugate hydrothermal systems functioning above a long-living magma chamber.     

临沧超大型锗矿床有机质与锗矿化的地球化学特征

临沧锗矿床是一产于第三系含煤岩系中的超大型矿床。矿床的最初锗源与盆地西缘的二云母花岗岩有关。主矿体产于下煤组沉积旋回的早期地层中，每一沉积阶段早期形成的褐煤和碳质泥岩中富含锗，最高含量达１４７０×１０＾－６。褐煤和碳质泥岩在矿化过程中平均富集了１６４－１６９倍。根据锗含量，褐煤和碳质泥岩可分为锗含量小于１２×１０＾－６的低锗煤（泥岩）和大于９０×１０＾－６的高锗煤（泥岩）。高锗煤中有机质富含氧官能     

内蒙古陈旗断陷东部伊敏组沉积相及铀成矿作用

陈旗断陷是位于内蒙古东部海拉尔盆地群的一个早白垩世断陷盆地,盆地盖层由铜钵庙组、南屯组、大磨拐河组和伊敏组构成,盆地近东西向展布,为地层倾向南东的单断式盆地.在伊敏组沉积时期,陈旗断陷进入萎缩阶段,盆地南部扇三角洲向盆地中心推进,盆地被淤浅并出现大量沼泽沉积,形成含煤地层,同时湖面向北萎缩,盆地北部缓坡形成小型河流三角洲沉积.铀矿化出现在前第四纪时期的沟谷附近,前第四纪沟谷或河道提供的含铀含氧水垂向侧向渗入到隔水层顶板处氧化褐煤,被炭质吸附而形成煤层上部的次生铀矿化,属于潜水氧化型铀矿化.     

临沧锗矿床的微量元素地球化学

采用ICP-MS测定了临沧锗矿中51个含矿煤、5个无矿煤、9个硅质岩样品的微量元素含量,并与基底二云母花岗岩进行对比,探讨了含矿煤与无矿煤的微量元素地球化学及其与锗超常富集的关系,得出几点认识: a 含矿煤、无矿煤和硅质岩中的大多数微量元素来自基底的二云母花岗岩; b 热水携带了成矿所必需的锗; c Nb可作为锗矿化的指示元素      

某新第三系盆地含铀的锗矿床的成矿特征及其成因探讨

我们在某新第三系盆地进行以铀为主,兼顾其它有用矿产的勘探工作中,落实了一个大型的含铀锗矿床。经工艺流程试验,锗铀均能综合利用。为了更好地认识、研究和寻找此类矿床,笔者特将该矿床的成矿特征及对其肤浅认识简介于下,以供读者和从事此类矿床的研究者们参考。     

陕西柞-山-商晚古生代拉分断陷盆地动力学与成矿作用

采用构造-岩相学和构造-热水沉积岩相填图研究,认为陕西柞水-山阳-商县（柞-山-商）晚古生代拉分盆地,在早古生代扬子板块北被动陆缘残余洋盆基础上,经历了志留纪-早泥盆世北秦岭岛弧造山带-残余洋盆转换过程。在中泥盆世演化为秦岭微板块北缘拉分断陷盆地,晚泥盆世叠加了深源碱性热流体叠加作用明显,形成了铁白云石钠质角砾岩相带,并发生了构造反转。石炭纪陆缘拉分盆地进一步发展演化为残余海盆萎缩封闭。这种造山带-沉积盆地-岛屿构造耦合与转换过程记录了由洋盆-岛弧碰撞造山转换为陆-陆碰撞造山过程。该拉分盆地中具有明显的区域成矿分带,与多期成矿成岩地质作用有关,在造山带-沉积盆地-岛屿构造耦合与转换中,中泥盆世柞-山-商拉分断陷盆地的四周被古陆块和造山带分隔,陆-陆碰撞过程驱动了造山带流体发生大规模排泄到该盆地内,在该拉分断陷盆地内形成了大规模热水沉积成岩成矿,各类热水沉积岩相发育。在该拉分盆地中,近东西向和北东向同生断裂作用形成了次级断陷盆地,为热水沉积成岩成矿提供了沉积容纳空间。热水沉积成因的银多金属-重晶石-菱铁矿矿床定位于三级和四级热水洼地。晚泥盆世-石炭纪近南北向的岩石圈地幔收缩,陆-陆碰撞收缩成为垂向热传输主要驱动力源,导致了陆壳尺度上碱性热流体被挤压垂向排出到陆表残余海盆之中,本区脉状富金镍钴铜矿与晚泥盆世-石炭纪深源碱性热流体隐爆作用形成的碱性铁白云石钠质角砾岩带密切有关。类卡林型金矿定位于该盆地上部基底构造层和盆地热水浊流沉积相内,主要与后期脆韧性剪切带有密切关系。     

Mineral and inorganic chemical composition of the Pernik coal, Bulgaria

The mineral and inorganic chemical composition of five types of samples from the Pernik subbituminous coals and their products generated from the Pernik preparation plant were studied. They include feed coal, low-grade coal, high-grade coal, coal slime, and host rock. The mineral matter of the coals contains 44 species that belong mainly to silicates, carbonates, sulphates, sulphides, and oxides/hydroxides, and to a lesser extent, chlorides, biogenic minerals, and organic minerals. The detrital minerals are quartz, kaolinite, micas, feldspars, magnetite, cristobalite, spessartine, and amphibole. The authigenic minerals include various sulphides, silicates, oxihydroxides, sulphates, and carbonates. Several stages and substages of formation were identified during the syngenetic and epigenetic mineral precipitations of these coals. The authigenic minerals show the greatest diversity of mineral species as the epigenetic mineralization (mostly sulphides, carbonates, and sulphates) dominates qualitatively and quantitatively. The epigenetic mineralization was a result of complex processes occurring mostly during the late development of the Pernik basin. These processes indicate intensive tectonic, hydrothermal and volcanic activities accompanied by a change from fresh to marine sedimentation environment. Thermally altered organic matter due to some of the above processes was also identified in the basin. Most of the trace elements in the Pernik coals (Mo, Be, S, Zr, Y, Cl, Ba, Sc, Ga, Ag, V, P, Br, Ni, Co, Pb, Ca, and Ti) show an affinity to OM and phases intimately associated with OM. Some of the trace elements (Sr, Ti, Mn, Ba, Pb, Cu, Zn, Co, Cr, Ni, As, Ag, Yb, Sn, Ga, Ge, etc.) are impurities in authigenic and accessory minerals, while other trace elements (La, Ba, Cu, Ce, Sb, Bi, Zn, Pb, Cd, Nd, etc.) occur as discrete phases. Elements such as Sc, Be, Y, Ba, V, Zr, S, Mo, Ti, and Ga exceed Clarke concentrations in all of the coal types studied. It was also found that a number of elements in the Pernik coals (F, V, As, Pb, Mo, Li, Sr, Ti, Ga, Ni, Ge, Cr, Mn, etc.) reveal mobility in water and could have some environmental concerns.     

云南镇康地区芦子园铅锌矿床控矿因素浅析

镇康芦子园矿床经初步评价为一大型铅锌多金属矿床,属于早期沉积(火山沉积)、后期热液改造的热液型矿床。矿体主要赋存于镇康复背斜北西翼的次级芦子园背斜的晚寒武世沉积地层中,是由晚寒武世的沉积成岩作用局部形成富含Pb、Zn、Cu、Ag等元素,后期经区域浅变质作用,特别是区内岩浆影响下的热变质和热液交代作用使元素发生迁移、富集而形成的,构造和层位等控矿明显,热液蚀变是区内找矿标志之一。矿体形成与矽卡岩化、硅化、大理岩化、磁铁矿化等蚀变有关,成矿与构造、深部断裂、岩浆活动、成矿热液活动密切相关。     

西藏sedex型矿床赋矿盆地性质对成矿元素的制约作用

“青藏高原热”的掀起，极大地提高了西藏境内基础地学的研究水平和认识程度，为正确把握西藏喷流型及其它类型矿产资源的战略地位奠定了良好的基础，在此基础上，通过对甲马，沙拉岗矿区的矿床学研究，笔者认为它们都受“盆，相，位”的严格控制，具有喷流沉积的一般特征，属sedex属矿床的范畴。但二者之间却又存在元素组成，矿物成分，结构构造等方面的明显差异。产生这种差异的根本原因在于其形成的大地构造背景和盆地性质不同。     

Basin Fluid Mineralization during Multistage Evolution of the Lanping Sedimentary Basin, Southwestern China

The Lanping sedimentary basin has experienced a five-stage evolution since the late Paleozoic: ocean-continent transformation (late Paleozoic to early mid-Triassic); intracontinental rift basin (late mid-Triassic to early Jurassic); down-warped basin (middle to late Jurassic); foreland basin (Cretaceous); and strike-slip basin (Cenozoic). Three major genetic types of Ag-Cu polymetallic ore deposits, including the reworked hydrothermal sedimentary, sedimentary-hydrothermally reworked and hydrothermal vein types, are considered to be the products of basin fluid activity at specific sedimentary-tectonic evolutionary stages. Tectonic differences of the different evolutionary stages resulted in considerable discrepancy in the mechanisms of formation-transportation, migration direction and emplacement processes of the basin fluids, thus causing differences in mineralization styles as well as in genetic types of ore deposit.     

临沧锗矿床地质特征

矿床位于临沧帮卖第三纪盆地。矿体主要赋存于Ｎ＾２１和Ｎ＾１１地层中,矿体受褐煤层及碳层控制,呈层状、似层状、透镜状产出。主矿体走向长４７２ｍ,倾斜长４００～８００ｍ,平均厚４ｍ,平均品位ω（Ｇｅ）＝０．０５５％,可分为锗煤型和锗砂岩两类矿石。锗主要来源于基底花岗岩,成矿可分为模特富集、沉积富集、成岩富集及后生改造富集四个阶段。     

东川桃园式铜矿Ar-Ar同位素年龄及意义

通过对东川桃园铜矿与铜矿共生石英的40Ar/39Ar同位素年龄的测定,得到马鞍形年龄谱,其坪年龄为768.43Ma±0.58Ma,等时线年龄为770.00Ma±5.44Ma。该矿床后期改造作用明显,并非同生沉积或成岩作用早期成矿,而与晋宁期Rodina大陆裂解有关。东川铜矿的形成可能是在Rodinia大陆裂解时,从深部带来大量成矿物质改造成岩时期初始的矿化,形成矿床的叠加富集和最终定位,因此,晋宁-澄江期是东川铜矿的主成矿期。     

有机质在卡林型金矿成矿过程中的作用

卡林型金矿与有机质之间存在着密切的联系。在表生过程中,有机质对金的溶解、吸附和生物吸收作用是沉积、成岩过程中金在赋矿层位中初步富集的重要地质营力,腐殖酸可能是表生金成矿过程中重要的迁移因素。在热液作用过程中,原油形成和二次运移不可能是金成矿迁移的主要因素,但成烃及成油后期有机质的热成熟和裂解作用所产生的有机酸及Ｈ２Ｓ可能对金的淋滤和迁移起着不可低估的作用。矿体及围岩中有机质的高成熟度,以及矿床及围     

四川盆地川中地区震旦系灯影组碳酸盐沉积物成岩作用与孔隙流体演化

以四川盆地川中高石梯-磨溪地区钻井岩芯和水样资料为主,盆地周边地面剖面露头资料为辅,采用微量元素、阴极发光、包裹体、同位素等分析手段进行岩石学和地球化学分析,在此基础上讨论了灯影组碳酸盐岩的成岩作用变化和成岩作用过程中孔隙流体的演化。研究结果表明:灯影组碳酸盐岩沉积物在沉积作用和成岩作用过程中广泛地受到孔隙流体和成岩作用变化的影响,发生过海水的胶结作用、早期大气水成岩作用（溶解作用和沉淀作用）、表生喀斯特化作用、构造控制的热液白云石化和密西西比谷型矿化作用、碳氢产生时的溶解作用、油热裂解时焦沥青的充填孔洞作用等,其中喀斯特化和热液白云石化对储层的发育起着重要的作用。然而,灯影组孔隙流体广泛地被白云石化作用和喀斯特化作用的修饰。现今地层水资料分析表明这些成岩作用明显地影响蒸发海水的地层水流体。地层水分析资料在Ca-Br及Mg-Br关系图上显示出蒸发海水的特征,Ca的浓度比蒸发海水分布曲线要高,Mg的浓度比蒸发海水曲线要低,为灯影组沉积物在成岩作用过程中发生过白云石化作用的结果。     

云南临沧煤型锗矿床中锗富集过程的有限元数值模拟

成矿元素富集作用是煤型关键金属矿床研究面临的主要问题之一。针对云南临沧煤型锗矿床中锗富集过程进行热-流-化-质多场耦合数值模拟研究。结果表明,数值模拟结果与前人研究结果吻合,验证了煤型锗矿床成矿理论及数值模拟方法在矿床学理论研究中的作用。岩体上表面形态是临沧锗矿床成矿的关键控制因素,具有穹隆形态的岩体上表面能够使含煤盆地底部产生9.1×10³倍的锗富集(相较于反应物浓度),在岩体规模减小50%的情况下仍有6.9×10³倍的富集,而凹陷和水平的岩体上表面分别只产生了589倍和9.3倍的锗富集。因此,具有穹隆形态的岩体上表面更有利于其上部的含煤盆地形成高品位的锗矿化,穹隆状岩体的上表面可为岩浆热液成因的煤型锗矿床深、边部找矿勘探提供有利信息。     

内蒙古西胡里吐盆地有机质特征及其与铀矿化的关系

在砂岩型铀矿床中 ,有机质与铀矿化之间有着较为密切的关系。西胡里吐盆地的有机质主要是以松柏类和蕨类等高等植物残体为母质的腐殖型有机质。通过镜质体反射率、有机质碎屑的颜色、粘土矿物X 衍射和古地温恢复等分析测试发现 ,有机质的成熟度较低 ,处于未成熟—低成熟早期阶段。有机质的类型和成熟度决定了其在热演化中产生了大量腐殖酸并保存在地层中。褐煤、腐殖酸、残余植物碎屑和地沥青等是现存有机质的主要类型。除大量产出的煤层外 ,有机质主要呈碎屑状和细分散状分布于地层之中。 70 %的岩石中有机质的丰度在 0 1 %～ 3 % ,对铀矿化的形成较为有利。铀与有机质的紧密共生以及二者之间的正相关性 ,表明了有机质在西胡里吐盆地铀矿化形成中所起的重要作用。有机质中的腐殖酸与铀矿化的关系最为密切 ,有机粘土复合体、蚀变岩屑、植物碎屑和地沥青等吸附剂对铀的吸附均与腐殖酸有关。腐殖酸吸附铀后可以将铀还原 ,还可以与铀酰离子等进行络 (鳌 )合形成铀酰腐殖酸盐 ,并最终引起铀的沉淀富集。     

Petrological,geochemical, and mineralogical compositions of the low-Ge coals from the Shengli Coalfield,China: A comparative study with Ge-rich coals and a formation model for coal-hosted Ge ore deposit

To better understand the formation mechanism of coal-hosted Ge ore deposits, this paper reports on the petrological, mineralogical, and geochemical compositions of the low-Ge coals in the Shengli Coalfield (Inner Mongolia, China), using optical microscopy, field emission-scanning electron microscopy, X-ray fluorescence, X-ray diffraction, and inductively coupled plasma mass spectrometry. The samples in the present study closely neighbor the previously-reported Wulantuga coal-hosted Ge ore deposit (both No. 6 Coal). In comparison with the Wulantuga Ge-rich coals, the low-Ge coals of the Shengli field display higher moisture (27.59% on average) and lower pyritic sulfur contents (0.53%). Both the low-Ge and Ge-rich coals are generally high in inertinite, and have varying but relatively low huminite contents. Preservation of fecal pellets as macrinite is notable in both the low-Ge and Ge-rich coals, and the position of the fecal pellets appears to be within tunnels or chambers within the wood. Quartz, kaolinite, pyrite, and gypsum are the major crystalline phases identified in most of the Ge-rich and low-Ge coals, but the low-Ge coals contain significantly less pyrite and are more abundant in non-mineral Ca and Mg. Ca-oxalate of authigenic origin is observed, generally occurring as cell-fillings in the low-Ge coals. Otherwise mineral-free organic matter in the low-Ge coals would be expected to have an inherent ash yield of around 6%, derived from the inorganic elements (mainly non-mineral Ca and Mg) that occur either in the organic matter or as dissolved ions in the pore water and form the sulfate species in low-temperature (oxygen-plasma) ash residues. The highly-elevated trace elements, including Be, Ge, As, Sb, W, Hg, and Tl, that occur in the Ge-rich coals of the Wulantuga deposit, are significantly depleted in the low-Ge coals. Lateral migration of Ge–W- and As–Hg–Sb–Tl-rich solutions through the original peat swamp for the Wulantuga Ge ore deposit has led to significant enrichment of Ge on the margin of the coal basin but decreasing Ge concentrations toward to the inner part of the basin. Such a migration direction is different to those in the previously-reported for the hydrothermal solutions in the Lincang (Yunnan of China) and Spetzugli (Russian Far East) Ge ore deposits, where the solutions migrated vertically from granite to peat along faults and led to a dome-shaped Ge distribution in the relevant coal seam.     

煤系战略性金属元素富集成矿的构造控制

煤系战略性金属矿产的聚集分布是多因素、多阶段、多层次综合作用的结果,地质构造控制作用是其中一个值得重视的因素。煤中战略性金属富集成矿的构造控制因素包括大地构造背景,构造运动,构造–岩浆活动等方面,体现在对金属矿产载体——含煤岩系的控制、对成矿物质来源的控制、对元素原生聚集和后期迁移重组的控制。从煤系矿产物源相关、耦合成矿、同盆共存的角度分析,构造作用对战略性金属富集成矿的控制贯穿于含煤盆地形成与演化的全过程。聚煤期前的构造运动奠定煤盆地基底构造格局,构造沉降和隆升提供了聚煤作用的场所和含煤岩系的物源区,从而决定了含煤岩系及其战略性金属元素的物质基础。聚煤期构造作用主要表现为盆–山耦合过程、同沉积期构造活动、岩浆作用等方式,通过对聚煤源–汇系统、岩相古地理与聚煤环境、泥炭沼泽类型及地球化学条件等因素的影响,决定成矿物质在泥炭化阶段和成岩作用阶段的迁移与原生聚集。聚煤期后的构造–热演化过程对金属元素迁移重组产生不同程度的影响,主要体现在构造沉降增温和岩浆热效应、构造格局与含矿热液活动、应力应变控矿机制,以及煤田构造定位决定矿床赋存状态。煤系战略性金属元素富集成矿构造控制研究应注重加强以下4个方面:与煤盆地沉积充填相关联的大地构造格局与演化、作为含矿流体运移通道的断裂构造特征、不同时期岩浆活动的影响差异性,以及应力应变的构造物理化学效应。