全球铅锌矿资源分布     

江少卿  徐毅  孙尚信  王策  李丽 《地质与资源》2020,29(3):224-232

世界范围内铅锌矿资源较为丰富，在全球50多个国家均有分布.通过搜集国内外铅锌矿相关的资料和信息，在对世界1035处铅锌矿床及3319个矿（化）点资料进行提炼、系统梳理的基础上，对不同数据来源的全球铅锌矿的储量和资源储量进行比较研究，对全球铅锌矿3种主要成因类型，即喷流沉积型、火山块状硫化物型和密西西比型铅锌矿的资源分布、成矿时间和成矿空间分布规律进行了全面的综合分析研究，对世界大型铅锌矿床的储量、资源储量、品位、成矿类型和成矿特征进行归纳总结，以期为全球铅锌矿的综合研究提供参考.  相似文献   

VMS矿床成矿流体的组成,来源及作用机制   总被引：5，自引：1，他引：5  

刘亮明  彭省临 《矿产与地质》1997,(6):374-380

ＶＭＳ矿床是一类非常重要的有色金属矿床，其成因与火山岩及海水密切相关。流体包裹体成分及氢氧同位素特征表明成矿流体主要为加热的海水，可能有岩浆水的参与。渗入火山岩层的海水在深部热源作用下发生对流，并萃取了火山岩中的金属。成矿流体在海底喷溢，与海水混合反应，造成矿石沉淀。整个成矿演化过程经历了复杂的流体—岩石反应和流体—流体反应，这些反应在成矿中起着非常重要的作用。  相似文献   

REE Geochemistry of VMS and SEDEX Ores in China     

Song Xuexin  Xu Qingsheng  Guo Yuemin  Mao Xueying  Ouyang Hong Institute of Mineral Deposits  Chinese Academy of Geological Sciences  Beijing Institute of High Energy Physics  Chinese Academy of Sinices  Beijing 《《地质学报》英文版》1997,71(3):263-272

REE ratios and patterns for massive pyrite ore and massive cuprous pyrite ore ofthe Baiyinchang orefield are quite similar to those for quartz keratophyritic tuff and quartzalbitophyre of the same orefield. However, massive cuprous pyrite ore of the Ashele Cu-Zn de-posit is similar to basalt-diabase of the same district in REE geochemistry. Comparison of theChinese VMS ores with those from Rio Tinto, Spain and Que River, Australia, in REEgeochemistry has been made. REE ratios and patterns of bedded-massive and massive ores ofthe Changba-Lijiagou Zn-Pb deposit, the second largest SEDEX deposit in China are similarto those of their host rocks, the Qinling shales of Devonian age and the Changba adamellite.The three types of ore and their host rocks of the Dongshengmiao pyrite (pyrrhotite)-Zn-Pbdeposit have parallel REE ratios and patterns.  相似文献   

Patterns in the spatial distribution of Peruvian anchovy (Engraulis ringens) revealed by spatially explicit fishing data   总被引：1，自引：0，他引：1  

Sophie Bertrand  Erich Díaz  Matthieu Lengaigne 《Progress in Oceanography》2008,79(2-4):379

Peruvian anchovy (Engraulis ringens) stock abundance is tightly driven by the high and unpredictable variability of the Humboldt Current Ecosystem. Management of the fishery therefore cannot rely on mid- or long-term management policy alone but needs to be adaptive at relatively short time scales. Regular acoustic surveys are performed on the stock at intervals of 2 to 4 times a year, but there is a need for more time continuous monitoring indicators to ensure that management can respond at suitable time scales. Existing literature suggests that spatially explicit data on the location of fishing activities could be used as a proxy for target stock distribution. Spatially explicit commercial fishing data could therefore guide adaptive management decisions at shorter time scales than is possible through scientific stock surveys. In this study we therefore aim to (1) estimate the position of fishing operations for the entire fleet of Peruvian anchovy purse–seiners using the Peruvian satellite vessel monitoring system (VMS), and (2) quantify the extent to which the distribution of purse–seine sets describes anchovy distribution. To estimate fishing set positions from vessel tracks derived from VMS data we developed a methodology based on artificial neural networks (ANN) trained on a sample of fishing trips with known fishing set positions (exact fishing positions are known for approximately 1.5% of the fleet from an at-sea observer program). The ANN correctly identified 83% of the real fishing sets and largely outperformed comparative linear models. This network is then used to forecast fishing operations for those trips where no observers were onboard. To quantify the extent to which fishing set distribution was correlated to stock distribution we compared three metrics describing features of the distributions (the mean distance to the coast, the total area of distribution, and a clustering index) for concomitant acoustic survey observations and fishing set positions identified from VMS. For two of these metrics (mean distance to the coast and clustering index), fishing and survey data were significantly correlated. We conclude that the location of purse–seine fishing sets yields significant and valuable information on the distribution of the Peruvian anchovy stock and ultimately on its vulnerability to the fishery. For example, a high concentration of sets in the near coastal zone could potentially be used as a warning signal of high levels of stock vulnerability and trigger appropriate management measures aimed at reducing fishing effort.  相似文献   

Applying the box plot to the recognition of footwall alteration zones related to VMS deposits in a high-grade metamorphic terrain, South Africa, a lithogeochemical exploration application     

H.F.J. Theart  R. Ghavami-Riabi  H. Mouri  P. Gräser 《Chemie der Erde / Geochemistry》2011,(2):143-154

Alteration zones (more commonly foot wall alteration zones) are related to volcanic-hosted massive sulfide (VMS) deposits and represent unique features that may be targeted during exploration. Of these, the chloritic foot wall alteration pipe is the most extensive and characteristic of VMS deposits. This feature is geochemically identified by a strong relative enrichment in aluminium and magnesium and a coupled depletion in calcium and sodium, giving rise to chloritic rocks in the primary environment of formation. During high grade regional metamorphism such chloritic precursor rock types are replaced by an unusual mineral paragenesis, typically containing magnesium rich cordierite, phlogopite, orthoamphiboles or orthopyroxenes and aluminium rich minerals such as sillimanite and corundum. This suggests that the unusual geochemical features of the alteration zone, retained during the deformation and metamorphism, should be recognisable in lithogeochemical exploration.The massive sulfide deposit in the eastern part of the metamorphic Namaqua Province, South Africa, at Areachap, Kantienpan and the defunct Prieska Cu–Zn Mine are hosted by a Mid-Proterozoic volcano sedimentary succession known as the Areachap Group. These deposits were affected by a complex deformation and metamorphic history and represent examples of upper amphibolite to granulite grade metamorphosed VMS deposits.The application of the known lithogeochemical methods is especially complicated where the geology is not well understood, due to the poor rock exposure of complexly deformed and metamorphosed areas, such as in the eastern part of the Namaqua Province.The box plot presents a more readily applicable lithogeochemical method to characterize and identify the alteration process, but it was designed for relatively un-metamorphosed environments. It is demonstrated here that the box plot may also be applied to high-grade metamorphic terrains and that the mineral phases used in defining the boxplot in low grade metamorphic environments may be replaced by their equivalents in high grade metamorphic terrains. The compositional trends of the metamorphic minerals themselves may be used in defining the boxplot for high grade metamorphic terrains. These include the transition of: annite to phlogopite; grossular to almandine or pyrope, augite to enstatite or clinoenstatite, and hornblende to gedrite or cummingtonite. Close to the ore zone, the relative Mg content of pyroxene, cordierite and biotite are higher than further away from this zone. It could be demonstrated that the changes in the mineral compositions are gradational when comparing unaffected rocks with progressively more altered wall rocks.Conclusions based on an application of the isocon method demonstrate that primary footwall alteration zones in the Areachap Group's VMS deposits are characterized by elemental depletion of Na₂O, CaO, Sr, Ni, V and La and enrichment of MgO, Fe₂O_3(total), S, Zn, SiO₂, Co and F. It is shown that the whole rock compositions of rocks that were independently identified as the metamorphic equivalents of altered rocks, using the isocon method, plot in the correct place in the box plot for high grade regionally metamorphosed terrains. This establishes the box plot as an effective and practical tool for lithogeochemical exploration for VMS deposits in complexly deformed high grade metamorphosed terrains.  相似文献   

Comparative Study of Gacun and Youre Silver–Lead–Zinc–Copper Deposits in Sichuan, SW China, and their Mineralization Significance     

DANG Yuan  CHEN Maohong  FU Bin  XUE Zhiqiang 《《地质学报》英文版》2018,92(1):162-182

The large Gacun silver–lead–zinc–copper deposit in Sichuan Province is one of the largest volcanogenic massive sulfide(VMS) deposits in China. The deposit consists of western and central ore bodies, which form a vein–stockwork mineralization system corresponding to hydrothermal channels, and eastern ore bodies, which form an exhalative chemical sedimentary system derived from a brine pool in a submarine basin. The Youre lead–zinc deposit, which is currently under exploration and lies adjacent to the southern part of the Gacun deposit, is characterized by intense silicification and vein–stockwork structures and consists of massive silicified rhyolitic volcanics, banded rhyolitic tuff, and phyllitic sericite tuff. From a comparison of their ore-bearing horizons, the Gacun and Youre deposits have a continuous and stable hanging wall(calcareous slate and overlying andesite) and foot wall(rhyolite–dacite breccia and agglomerate), and the lithologic sequence includes lower intermediate to felsic rocks and upper felsic rocks. Thus, the Youre deposit, which comprises relatively thinly layered low–grade ore, is regarded as forming a southward extension of the Gacun deposit. A further comparison of the structures of the ore-bearing belts between the two deposits suggests that the Youre ore bodies are similar to the western ore bodies of the Gacun deposit. Moreover, the characteristics of fluid inclusions and stable isotopes in the Youre deposit are also similar to those of the western ore bodies of the Gacun deposit. Genetic models of the deposits are proposed for the Gacun–Youre ore district, and massive concealed ore bodies may occcur in the Youre deposit at depths that are similar to those of the eastern ore bodies of the Gacun deposit.  相似文献   

三江成矿带开心岭矿区尕的考组火山活动与多金属矿的成矿关系     

李洪普  陈学明  左志勇  窦全成  芦文泉 《西北地质》2012,45(1):71-78

在野外地质观察、室内鉴定分析的基础上,对开心岭多金属矿区地层进行了重新划分,同时对成矿地质特征及成矿机理进行了论述.矿区由4个矿段组成,共圈定铁矿体15条(含8条隐伏矿体).其中,10条为铁矿体,5条为锌矿体.各矿体皆产于早二叠世开心岭群尕的考组火山岩中,根据岩相及岩性组合,推断该火山岩在3次喷发期内构成了6个韵律层.提出该矿床成因类型属火山喷流(VMS)型锌多金属矿床,火山岩是区内重要的找矿标志.  相似文献   

滇西北维西陆缘弧月亮坪早三叠世VMS型铅锌矿床的发现及地质意义     

李守奎  刘学龙  刘思晗  张世涛  赵庆红  杨学雄 《地质学报》2022,96(4):1239-1264

滇西北维西陆缘弧夹持于扬子地块和兰坪地块之间,是古特提斯时期形成的火山弧,中—下三叠统攀天阁组酸性端元和崔依比组基性端元构成的双峰式火山岩是其主要组成部分,被视为研究古特提斯洋俯冲和闭合过程的关键区带.本文初次在该火山岩带攀天阁组长英质火山岩中发现了1处V MS型矿床——月亮坪铅锌矿.初步野外调查显示,铅锌矿体具有"上...  相似文献   

Genesis of the Zinkgruvan stratiform Zn-Pb-Ag deposit and associated dolomite-hosted Cu ore,Bergslagen, Sweden     

《Ore Geology Reviews》2017

Zinkgruvan, a major stratiform Zn-Pb-Ag deposit in the Paleoproterozoic Bergslagen region, south-central Sweden, was overprinted by polyphase ductile deformation and high-grade metamorphism (including partial melting of the host succession) during the 1.9–1.8 Ga Svecokarelian orogeny. This complex history of post-ore modification has made classification of the deposit difficult. General consensus exists on a syngenetic-exhalative origin, yet the deposit has been variably classified as a volcanogenic massive sulfide (VMS) deposit, a sediment-hosted Zn (SEDEX) deposit, and a Broken Hill-type (BHT) deposit. Since 2010, stratabound, cobaltiferous and nickeliferous Cu ore, comprising schlieren and impregnations of Cu, Co and Ni sulfide minerals in dolomitic marble, is mined from the stratigraphic footwall to the stratiform Zn-Pb-Ag ore. This ore type has not been fully integrated into any of the existing genetic models. Based on a combination of 1) widespread hematite-staining and oxidizing conditions (Fe₂O₃ > FeO) in the stratigraphic footwall, 2) presence of graphite and reducing conditions (Fe₂O₃ < FeO) in the ore horizon and hangingwall and 3) intense K-feldspar alteration and lack of feldspar-destructive alteration in the stratigraphic footwall, we suggest that both the stratiform Zn-Pb-Ag and the dolomite-hosted Cu ore can be attributed to the ascent and discharge of an oxidized, saline brine at near neutral pH. Interaction of this brine with organic matter below the seafloor, especially within limestone, formed stratabound, disseminated Cu ore, and exhalation of the brine into a reduced environment on the sea floor produced a brine pool from which the regionally extensive (>5 km) Zn-Pb-Ag ore was precipitated.Both ore types are characterized by significant spread in δ³⁴S, with the sulfur in the Cu ore and associate marble-hosted Zn mineralization on average being somewhat heavier (δ³⁴S = −4.7 to +10.5‰, average 3.9‰) than that in the stratiform Zn-Pb-Ag ore (δ³⁴S = −6 to +17‰, average 2.0‰). The ranges in δ³⁴S are significantly larger than those observed in syn-volcanic massive sulfide deposits in Bergslagen, for which simple magmatic/volcanic sulfur sources have been invoked. Mixing of magmatic-volcanic sulfur leached from underlying volcanic rocks and sulfur sourced from abiotic or bacterial sulfate reduction in a mixing zone at the seafloor could explain the range observed at Zinkgruvan.A distinct discontinuity in the stratigraphy, at which key stratigraphic units stop abruptly, is interpreted as a syn-sedimentary fault. Metal zonation in the stratiform ore (decreasing Zn/Pb from distal to proximal) and the spatial distribution of Cu mineralization in underlying dolomitic marble suggest that this fault was a major feeder to the mineralization. Our interpretation of ore-forming fluid composition and a dominant redox trap rather than a pH and/or temperature trap differs from most VMS models, with Selwyn-type SEDEX models, and most BHT models. Zinkgruvan has similarities to both McArthur-type SEDEX deposits and sediment-hosted Cu deposits in terms of the inferred ore fluid chemistry, yet the basinal setting has more similarities to BHT and felsic-bimodal VMS districts. We speculate that besides an oxidized footwall stratigraphy, regionally extensive banded iron formations and limestone horizons in the Bergslagen stratigraphy may have aided in buffering ore-forming brines to oxidized, near-neutral conditions. In terms of fluid chemistry, Zinkgruvan could comprise one of the oldest known manifestations of Zn and Cu ore-forming systems involving oxidized near-neutral brines following oxygenation of the Earth’s atmosphere.  相似文献   

新疆阿尔泰阿舍勒铜锌矿床矿物学特征及其地质意义   总被引：1，自引：0，他引：1  

张振龙  杨富全  李强  杨成栋 《矿床地质》2020,39(5):905-925

新疆阿尔泰阿舍勒铜锌矿床位于阿舍勒盆地,矿体赋存于中-下泥盆统阿舍勒组海相火山-沉积岩系中,为典型的VMS型矿床。Ⅰ号矿化带主矿体为铜-锌矿体,呈似层状产于凝灰岩与玄武岩之间,补给通道相细脉-网脉状铜矿化。Ⅱ号矿化带产于凝灰岩中,上部为层状重晶石矿化,补给通道相为细脉-网脉状铜铅锌银矿化。文章对脉状矿化中黄铁矿、闪锌矿、黄铜矿、方铅矿、黝铜矿、辉碲铋和绿泥石进行了矿物学研究,电子探针分析表明,硫化物主成分含量接近其理论含量。黄铁矿中w（Fe）/w（S＋As）比值平均为0.874,暗示脉状矿化形成深度为中浅部。闪锌矿中w（Fe）较低,指示其在低温环境下形成。绿泥石为蠕绿泥石,形成温度为157~206℃,平均为190℃。黝铜矿普遍含Zn,可达到8%,Ⅰ号矿化带黝铜矿富砷,Ⅱ号矿化带富锑,指示Ⅱ号矿化带矿物形成时的温度相对Ⅰ号矿化带低。脉状矿体中Au主要赋存于黄铁矿、黄铜矿、黝铜矿和闪锌矿中,Ag主要赋存在黝铜矿中,可达2.365%,Se主要赋存在辉碲铋矿中,平均1.242%。脉状矿化的矿物在中、低温度,较高硫逸度的环境下形成。矿体从底部到上部硫逸度总体趋势降低并且层状矿体和脉状矿体为同期同源热液活动的产物。  相似文献