邹家山铀矿床含矿裂隙系统研究

邹家山铀矿床位于相山铀矿田西部,是相山铀矿田最重要的矿床,该矿床属于受断裂裂隙构造控制的脉状中-低温热液矿床,以规模大、品位高而著称。对邹家山铀矿床露天采场含矿构造的详细调查显示,含矿裂隙系统由许多弧形小断层及其所夹持的透镜状岩块构成;含矿裂隙主要为北北东向和北北西向,次为其他方向;含矿裂隙是由"X"剪节理基础上发展起来的,经过持续变形而形成;矿液充填交代时NNE向断裂具有一定的左行特点,近南北向裂隙往往是矿脉膨胀部位;成矿流体压力比较大,具有明显的水压致裂作用,形成同一露头上多个方向弧形和不规则铀矿脉,并且有从高一级裂隙向低级别裂隙、微裂隙边矿化边扩展的特点。邹家山铀矿床矿带(矿体群)呈斜列状分布,平面上呈左列式,单体北东走向,轴线北东东走向;剖面上单体中-陡倾角,轴线中-低倾角倾向西。矿带(矿体群)的空间分布与邹家山-石洞断裂带明显不一致,反映出矿带可能受一组走向北东东(50°～65°)、中-缓倾角(30°～45°)倾向北西的隐性构造控制,而不是受陡倾角的北东向邹家山-石洞断裂带控制。就邹家山铀矿区而言,进一步找矿方向在现有矿带的南西西方向深部。     

湖南衡阳清水塘矿区断裂构造控矿特征

清水塘矿田位于断裂带中,矿体的形态、产状、规模及矿化富集除与地层岩性有关外,主要受断裂破碎带控制。通过分析清水塘区域构造控矿特征和矿区断裂构造控矿特征,总结了清水塘矿区断裂构造控矿的特点,认为多组断裂以及背斜和断裂的交汇部位均是铅锌矿体的主要富集部位;在成矿演化过程中,由于构造-岩浆活动及含矿热液的运移,断裂张开,热液充填沉淀结晶形成矿脉;当一部分矿液渗透到围岩中,继续沿微裂隙转移、萃取、活化、重新产生压裂,使裂隙张开,在构造-岩浆活化影响下,形成新的矿体。深大断裂作为导矿构造控制着含矿热液的运移空间,次级断裂作为容矿构造控制着矿化的富集部位。     

胶东地区望儿山断裂带成矿构造分析和找矿方向研究

通过望儿山断裂带构造控矿规律总结和成矿构造演化分析,建立区域构造成矿模式.望儿山断裂带构造控矿规律为:矿床在断裂带走向上呈似等间距分布;断裂带的上下盘均可成矿,矿体在断裂带中分布具有多层性;断裂带倾斜延深度大,控制矿体深度亦大;矿床在剖面上均呈“S”型产出,显示断裂成矿期具正向滑移性质;断裂带上各矿床矿体普遍向南西侧伏...     

山东望儿山断裂河东—上庄段控矿构造性质与演化

为厘清胶东金矿矿集区控矿断裂性质及其演化历史,本文以焦家断裂带的次级断裂——望儿山断裂为研究对象,在宏观地质调查基础上,通过含矿节理统计与共轭节理判别,恢复出测区成矿前和成矿期的构造应力场。该断裂是河东金矿和上庄金矿的主要容矿断裂,走向北东,倾向北西,局部与玲珑型花岗岩和郭家岭型花岗闪长岩接触带复合。节理统计显示,与主断裂带成小角度相交或近平行的节理往往充填有黄铁矿,通过含矿共轭剪节理恢复的河东与上庄矿区成矿期主压应力方向分别为277°∠13°和291°∠21°,即望儿山断裂在成矿期呈逆断层性质;河东矿区的一组共轭剪节理恢复的主压应力方向为188°∠2°,指示望儿山断裂曾发生过左行平移运动,这与焦家断裂带形成的地质背景相吻合,指示为成矿前断裂性质。对望儿山断裂旁侧次级断裂性质分析和产状测量以及Win Tensor软件分析结果表明,望儿山断裂在成矿后受到99°∠63°方向主压应力作用,断裂呈拉张性质。     

胶东金矿成矿构造──地球化学动力学研究

通过对胶东区域断裂构造时空演化的分析，提出郯庐大断裂的次级断裂为胶东金矿的控矿构造，并为导矿构造。晚燕山期区域右行走滑断裂活动产生的浅部张剪裂隙为容矿构造，其张裂变形产生的扩容作用是“泵吸”深部矿液上侵充填的驱动力。张剪断裂以脉动方式释放构造应力，实测差应力值为１２０～４０ＭＰａ；从早到晚有衰减趋势。容矿断裂脉动活动可划分为脆性破裂和脆韧性扩张两种动力学状态或阶段，并制约着热液反应体系中成矿和控制反应进行的方向和强度，从而控制成矿元素的富集和分散。热液成矿反应体系的热力学演化与构造动力学条件的耦合是金富矿石形成的机制。     

相山北部善堂庵地区北东向断裂对铀成矿的控制作用

善堂庵地区处在控制相山铀矿田富大矿床产出的邹家山-石洞断裂的北东向延伸端,区内主要发育东西向和北东向断裂。东西向断裂是控岩、控矿构造(早期控岩、晚期控矿);北东向断裂产状较陡,深切基底,成矿期活动强烈,常常与之前的东西向构造复合,深部流体和含矿热液沿其上升,形成较好的铀矿化。善堂庵地区铀矿化主要受花岗斑岩体及北东向巴泉-善堂庵断裂、邹家-布水断裂控制,区内多期、多序次构造发育,热液活动强烈,斑岩体广泛分布,铀成矿地质条件优越,具有良好的成矿远景。     

江西相山铀矿田构造控矿规律研究

对江西相山铀矿田内断裂构造格架及火山构造特征做了研究,认为相山火山盆地和断裂构造的成生与发育受永丰-抚州深断裂演化控制。从构造控矿作用看,相山铀矿田受大型中心式塌陷火盆控制,北部的EW向断裂带和中西部的EW向构造断陷带控制着矿田内的矿集带,NE向与EW向断裂构造复合部位控制了矿床的位置,密集成群的断裂裂隙带控制着铀矿体,使各矿床中的铀矿体呈群脉型。这些铀矿田地质构造特征及控矿规律对进一步找矿具有重要的指导意义。     

胶西北红布金矿地质特征及构造解析

胶西北红布金矿在焦家金矿田独具特色，它不同于一般意义上的构造蚀变岩型金矿，是发育在断裂带两侧花岗（闪长）质岩石中受密集节理裂隙带控制的细脉，网脉状金矿，构造解析表明红布金矿体主要形成于主断裂发生右行走滑的构造应力环境，基信压应力方位大致为SWW-NEE，主压应力轴近水平，含矿裂隙表现为张剪性质。     

吉林省永吉县倒木河金矿控矿构造特征

倒木河金矿为吉林中部矿化集中区中主要矿床,区域大地构造环境决定了矿化集中区的成矿地质条件和区域成矿系列的产出。区域上北东向小城子－口前,双河镇－西阳两条左行剪切断裂和小城子－双河镇北西向断裂为导岩,导矿构造,控制该矿床的产出。两条北东向左行剪切断裂产生的次级裂隙构造控制矿体和矿脉的产出,为矿床的容矿构造,从该区所具有区域构造环境至区域控矿断裂构造到次级容矿裂隙构造,构成了三级控矿系统,控矿断裂和裂     

福建上杭紫金山铜金矿床控岩控矿构造分析

紫金山铜金矿床的形成与构造作用关系十分密切；NE向梅造控制了燕山早期花岗岩的展市，NE与KW向构造结点控制了紫金山火山机构以及中酸性浅成一超浅成岩体。隐爆角砾岩受NW向断裂、裂隙带控制；紫金山矿区的石英-绢云母蚀变主要受区域构造一岩浆活动的控制。石英-地开石、石英-明矾石蚀变与救火山热液作用有关．主要受NW向断裂和裂隙密集带控制，紫金山矿区的铜金矿化带和矿体明显受断裂构造、火山构造的双重控制。成矿作用以裂隙充填交代方式为主．含矿裂隙带在走向和倾向上皆呈右行侧列：紫金山矿床的铜金成矿活动与燕山晚期的火山-构造活动有关。     

钦杭带南段庞西垌-金山银金矿田控矿构造分析及找矿指示

钦杭成矿带南段的庞西垌-金山银金矿田位于粤东与桂西交界处,包括庞西垌、金山、中苏、竹根坡、高村等银金矿床及一系列银金矿点,是20世纪80年代规划的十大银矿基地之一。庞西垌地区经历了多期的构造-岩浆活动,韧性剪切带和断裂构造尤其发育。印支期以来,可识别出3期主要构造:第一期为右行韧性剪切,前人利用糜棱岩中白云母测得时代为221 Ma;第二期为左行韧脆性剪切,北东向的庞西垌-金山断裂带反映最为突出,切过燕山晚期花岗岩;第三期为脆性走滑。银金矿体及矿石结构、构造主要受第二期左行韧脆性剪切带控制。应用里德尔剪切体系对控矿构造的分布特征分析显示,银金矿脉主要赋存于里德尔体系的D、R和T裂隙中;D裂隙是最重要的赋矿构造,热液蚀变岩型和石英脉型矿体呈透镜状左行斜列于主断裂面中,沿走向往南西侧伏;R和T裂隙主要发育梳状含金石英脉。R裂隙呈密集剪破裂产出,与主断裂面夹角15°~35°;T裂隙呈雁列状等距分布,与主断裂面夹角约为45°。这些矿脉就位体系,可以为该区进一步找矿作参考。     

Mineralization and Ore-controlling Implications of Low-angle Faults

Low-angle faults include those occurring in thrust-nappe structures in a compressive setting and the detachment of metamorphic core complexes in an extensional setting. All low-angle faults have their own particularities. The low-angle fault plays an important role in controlling over some endogenetic metallic ore deposits. Based on studies of the Xiaoban gold deposit, Xinzhou gold deposit, and Longfengchang polymetallic ore deposit, and comparisons with other mines, the authors conclude the ore-controlling implications of low-angle faults as follows. (1) Because of high temperature and high pressure, as well as strong ductile deformation, the internal energy of the elements rises in the large-scale deep ductile low-angle faults, which causes the elements to activate and differentiate from the source rocks, forming ore-bearing hydrothermal solution, and bring mineralization to happen. (2) When rising from depths and flowing along the low-angle faults, the ore-bearing hydrothermal solution will alter and     

Structural controls on carbonate-hosted Pb–Zn mineralization in the Dongmozhazhua deposit,central Tibet

Fault zones control the locations of many ore deposits, but the ore-forming processes in such fault zones are poorly understood. We have studied the deformation and ore textures associated with fault zones that controlled the lead–zinc mineralization of the Dongmozhazhua deposit, central Tibet, ∼100 km southwest of Yushu City. Geological mapping shows that the structural framework of the Dongmozhazhua area is defined by NW–SE-trending reverse faults and superposed folds that indicate at least two stages of deformation. The first stage is characterized by tight nearly E–W-striking folds that formed during the closure of the Jinshajiang Paleo-Tethyan Ocean in the Triassic. The second stage of deformation produced NW–SE-trending reverse faults and related structures of the Fenghuoshan–Nangqian fold-and-thrust belt associated with India–Asia collision in the late Eocene to Oligocene. Scanline surveys along the ore-controlling fault zones show an internal structure that comprises a damage zone, a breccia zone with clasts that have become rounded, and a breccia zone with lenticular clasts, and this complex architecture was formed during at least two compressional substages of deformation. The Pb–Zn mineralization in the Dongmozhazhua area occurs exclusively close to NW–SE-trending reverse fault zones. Microtextural observations reveal that mineralization occurred as veinlets and disseminated blebs in limestone clasts, and as continuous bands and cements in fractured rocks. Cataclastic sulfide grains also can be seen in the matrix of some fault zones. The types of mineralization differ with structural position. The fillings of the ore-bearing veinlets typify the products of hydraulic fracture and both types of mineralization took place concurrently with regional contraction. We consider, therefore, that the ore-bearing fluids in the Dongmozhazhua deposit were concentrated in fault zones during regional compression and that the ore minerals were precipitated during hydraulic fracturing of host rocks. Subsequent fault activity pulverized some pre-existing sulfide material into cataclastic grains in the matrix of a tectonic breccia that developed in the same faults.     

Structures and Implications for Fluid Migration in the Jiadi Carlin‐Type Gold Deposit,Guizhou Province,Southwest China

The Jiadi gold deposit is a newly discovered Carlin‐type gold deposit in the Guizhou Province, Southwest China. This deposit is structurally controlled by a shallow fold–fault superimposed system along the Lianhuashan trend. Field geological investigations, structural analysis, and mathematical research are conducted to study its structures and hydrothermal fluid flow process. Geological investigations (i.e. sections, stope, and drill hole) indicate that the structures are dominated by NE‐trending folds, NWW‐trending folds, and faults. A trend‐surface analysis of the low interformational fracture zone suggests that the overall distribution of the Lianhuashan trend is controlled by the NE‐trending Lianhuashan anticline. Nearly all primary Carlin‐type gold deposits are distributed along the southeastern flank where the fold axis changes from NE to EW. Gold orebodies are hosted by the interformational fracture zones and primarily situated at the transitions from the high‐value areas to the low‐value areas of the interformational fracture zones. A stress analysis on the hydrothermal veins indicates that they are of tenso‐shear properties. The ore‐forming elements (Au, As, Sb, Hg, and Tl) of the hydrothermal veins from the interformational fracture zones and intrusive breccia body present strong positive anomalies compared with those from the adjacent wall rocks. According to the development patterns of the ore‐forming elements and hydrothermal veins, a migration process of the ore‐forming fluids is proposed: the deeply sourced ore‐forming fluids migrated vertically to shallow crust along an intrusive breccia body, subsequently flowed horizontally along the interformational fracture zones accompanied by gold precipitation in the early stage, and finally migrated outward along steep micro‐fractures during following stages.     

粤北长江铀矿田控矿构造解析

控矿构造研究是长江铀矿田的薄弱环节,制约了成矿规律的深入探讨和进一步找矿方向.通过对矿田内控矿构造的详细解析,厘定了控矿构造形式,构建了构造控矿模型,探讨了控矿构造的演化,指出了找矿方向.铀矿田内的矿体和矿化带受北北西(近南北)向展布的小型断裂构造控制,具有走向延伸长、倾向延深大、产状比较稳定、局部弧形形态、呈带状成群...     

湖南凤凰地区地质构造与汞铅锌矿成矿关系研究

汞铅锌矿是湖南凤凰地区的优势矿种。介绍了该区汞铅锌矿的地质特征及类型,结合实际地质资料,综合分析了该区构造控矿因素,初步提出了该区汞铅锌矿的构造控矿规律: 区内汞铅锌矿床成因类型主要有层控叠加(沉积改造)型矿床和断层破碎带低温热液充填型脉状矿床; 导矿构造为NNE向和NE向区域性大断裂——保靖—铜仁断裂; 控矿构造为NNE向和NE向背斜核部及两翼,以及背斜与向斜转折部位; 容矿构造为NW向小断裂、容矿层中节理裂隙、层间裂隙及破碎带。     

贵州省青杠林铅锌矿床主构造特征及找矿远景浅析

根据矿区内大比例尺地质测量及主构造微量元素分析结果,对矿区内主构造特征、含矿性以及矿床的成矿规律、控矿因素进行了解析。青杠林铅锌矿床铅锌元素在多期构造活动时,随热液通道向上迁移,并在导矿构造两侧的层间破碎带、韧性剪切带内富集成矿。矿床成因类型属中低温热液充填交代型铅锌矿床。本文结合区域铅锌矿成矿规律及成矿条件对青杠林铅锌矿床的找矿远景作出了初步的评价。     

山东淄河断裂带成因机制与控岩控矿分析

山东淄河断裂带由近于平行的3～5条断裂构成,具多期活动性,经历了早期左行压扭为主—中期张性为主—晚期右行压扭为主的发展阶段：早期平推扭动所产生的层间裂隙和层间空隙为成矿热液交代沉淀提供了有利空间,铁矿化及矿体形态受断裂构造和层间构造的严格控制;中期的张性构造活动引发了地壳深部岩浆热液活动,提供了矿质来源;淄河式铁矿形成后,晚期右行压扭构造活动使矿体遭受破坏,断裂带南端被EW向断裂切截,该断裂带是淄河地区的控岩控矿构造,不仅提供了含矿热液上升运移的通道,而且造就了矿液沉淀储集的空间。淄河式铁矿主要赋矿层位为寒武—奥陶系九龙群炒米店组中下部及马家沟群北庵庄组和五阳山组,岩层钙质含量高、硅质含量低、性脆、裂隙发育,易于交代成矿,形成品位高、规模大的矿体（床）。淄河断裂带转弯并有分支断裂复合或次生断裂及与其交叉切割的NW向断裂交会处,不仅控制着燕山晚期闪长岩体的分布,而且是形成中低温热液交代充填-风化淋滤型（淄河式）铁矿大矿、富矿的有利部位。     

Geology and Mineralization at the Dajing Tin-polymetallic Ore Deposit, Inner Mongolia, China

Abstract: Dajing is a large-scale tin–polymetallic ore deposit in north China with Sn, Cu, Pb, Zn, Ag, and minor elements such as Co and In. The deposit is controlled by a passage-host structure system. Two groups of NE direction faults such as F₂ and F₁ are characterized by sinistral and multiphase activities, and the syn-ore NE faults with their derivative faults nearly in N-S direction constitute an important structure system as channelway for ore fluid. Around F₂ fault (mineralization center), metallic elements display horizontal zoning outwards from Sn, Cu to Cu, Sn, Pb, Zn, Ag and to Pb, Zn, Ag. Controlled by sinistral pull-apart vein system, the WNW direction host structure yielded the ore vein to "W" shape on horizontal plan while to staircase shape on vertical profile. Multiperiodic activities of the host structures system lead to multistage of ore mineralization. Four mineralization stages are recognized in the main mineralization, i.e. 1) cassiterite–arsenopyrite–quartz stage, 2) cassiterite-sulfide (or Cu–poly–metallic mineralization) stage, 3) massive pyrite stage, and 4) galena-sphalerite stage. Besides, fluid activities are identified here at the pre-mineral stage of the formation of quartz veins and sheared deformation, and at the post-mineral stage of quartz–calcite–fluorite deposition.
The earlier tin-rich ore solution raised from NE faults and its nearly N-S derivatives filled the NW-WNW direction fractures, and formed tin ore veins. Subsequent mineralization of Cu-polymetallic stage, pyrite stage and galena-sphalerite stage, overlapping on the same fracture system, sequentially expanded outwards from the fractures, and produced different kinds of ore types and mineralization zoning.     

Geologic and geochemical study of the Picacho gold mine, California: gold in a low-angle normal fault environment

The Picacho gold deposit, located in southeasternmost California, is a low-grade gold deposit in a nearly flat-lying denudational fault of regional extent and probable Oligocene age. The deposit is hosted by intensely fractured and faulted Mesozoic leucogranite and by chloritic augen gneiss and schist, and is overlain unconformably and in fault contact by unmineralized late Oligocene Quechan volcanic rocks. The deposit is structurally characterized by normal and normal-oblique faults of low to high dip at shallow depths in the mine, merging downward with a synchronous, low-dipping ore-stage extensional fault system (the Chocolate Mountains/Gatuna Fault) of probable Oligocene age in deeper portions of the deposit. The fault system was infiltrated during much of its active life by hot, dilute, highly exchanged meteoric water having temperatures of 170°–210° C, salinity <2 wt% NaCl equivalent and calculated δ¹⁸O_fluid between −2.6‰ and 5.2‰. This main-stage fluid precipitated quartz, pyrite, and specular hematite, accompanied by silicification and sericitization. Auriferous ore-stage pyrite was precipitated late in the fault evolution probably by mixing of reducing ore fluid with relatively oxidized main-stage fluid during regional Oligocene extension on the Chocolate Mountains/Gatuna Fault. The Picacho deposit is characterized by a gold–arsenic–antimony geochemical signature consistent with bisulfide complexing of gold in reducing fluid, in contrast with typical denudation fault-hosted base-metal-rich deposits associated with high-salinity fluids elsewhere in the southwestern United States. The deposit is overprinted by Miocene normal faults having a wide range of dips. These postore faults are associated with red earthy hematite precipitation, pyrite oxidation, and supergene enrichment of gold. Editorial handling: L. Meinert