共查询到20条相似文献，搜索用时 15 毫秒
1.
沉积喷流型矿化的岩石学证据——以大兴安岭南段黄岗和大井矿床为例 总被引：21，自引：3，他引：21
沉积喷流型矿床往往有各种喷流岩（热水沉积岩）的共生，正确识别这些喷流岩经常能为认识矿床的成因提供关键证据。大兴安岭南段是我国北方著名的锡－多金属成矿区，燕山期火山－侵入岩广泛出露，因此认为区内矿床大都是与燕山期岩浆活动有关的热液矿床。但是，区内近90％的矿床却产在二叠纪地层中，显示了与二叠纪沉积地层的密切联系。本文以其中的黄岗铁－锡矿床和大井锡－多金属矿床为例，对与矿石密切共生的热水沉积岩开展了系统的地质学、岩相学、矿物学和组构学研究，并结合必要的地球化学数据，证明大兴安岭南段在二叠纪沉积盆地演化过程中可能普经有重要的水下热液沉积喷流成矿作用发生，尽管历来被人们所忽视，但其重要性可能并不亚于燕山期的岩浆热液成矿作用。黄岗矿床的层状矽卡岩与二叠纪海底火山活动关系密切，是一种很具特色的喷流岩；而被误认为是燕山期流纹斑岩的大井矿床菱铁织云硅质岩可能是一种产在陆相断陷盆地、与锡铜铅锌银多金属矿化有关的新类型热水沉积岩。显然，与热水沉积喷流矿床紧密共生的热水沉积岩是认识该类矿床至为重要的岩石学证据之一。 相似文献
2.
《International Geology Review》2012,54(7):846-878
The Da Hinggan Mountains mineral province (DHMP), northeastern China, is divided into three tectonic units and corresponding metallogenic belts. The tectonic units of the Da Hinggan Mountains are the Erguna fold zone on the northwest, the Hercynian fold zone on the north, and the Hercynian fold zone on the south. The corresponding metallogenic belts are the Erguna Cu-Pb-Zn-Ag-Mo-Au belt of the NW DHMP, the Cu-Pb-Zn-Mo-Fe-Au belt of the northern DHMP, and the Pb-Zn-Ag-Cu-Sn-Fe-Mo belt of the southern DHMP. Distinct ore bodies, mostly associated with Mesozoic granites and volcanics, comprise (1) hydrothermal vein deposits including Pb-Zn-Ag-(Cu) and W‐Sn-Cu, (2) exhalative (Pb-Zn-Ag, Cu) deposits, (3) porphyry (Cu, Au, Mo), (4) skarn (Fe, Zn, Cu), and (5) epithermal Au-Ag deposits. The hydrothermal veins are hosted by a range of different rock types, whereas the exhalative ores are confined to Permian strata. The porphyry deposits occur within granite porphyries. The epithermal deposits are related to Mesozoic volcanic-subvolcanic rocks and occur within superjacent igneous structures. The first type, represented by the Bairendaba deposit, shows many characteristics of hydrothermal deposits. The second type occurs in a Permian clastic-chemical sedimentary sequence. Most Fe-Zn-Cu deposits related to granites and granodiorites are skarns. Granodiorite and granite-related deposits are typical porphyry ores, formed during Hercynian and Mesozoic time. Promising metallogenic conditions and the recent discovery of many large metal deposits indicate that this mineral province has a great exploration potential. 相似文献
3.
The lower valley of Changjiang, from Wuhan of the Hubei Province in the west to Zhenjiang of the Jiangsu Province in the east, contains more than 200 polymetallic (Cu–Fe–Au, Mo, Zn, Pb, Ag) deposits and is one of the most important metallogenic belts in China. This metallogenic belt, situated at the northern margin of the Yangzi craton and bordered by the Dabieshan ultrahigh pressure metamorphic belt to the north, consists mainly of Cambrian–Triassic marine clastic sedimentary rocks and carbonate and evaporite rocks, which overlay a Precambrian basement and are intruded by Yanshanian (205 to 64 Ma) granitoid intrusions and subvolcanic complexes. Repeated tectonism from Late Proterozoic to Triassic resulted in extensively developed networks of faults and folds involving the Cambrian–Triassic sedimentary strata and the Precambrian basement. The Yanshanian granitoid intrusions and subvolcanic complexes in the Lower Changjiang metallogenic belt are characterized by whole-rock δ18O of +8‰ to +10‰, initial 87Sr/86Sr of 0.704 to 0.708, and εNdt from −10 to −17 and have been interpreted to have originated from mixing between juvenile mantle and old crustal materials. Also, the Yanshanian granitoids exhibit eastward younging and increase in alkalinity (i.e., from older calc–alkaline in the west to younger subalkaline–alkaline in the east), which are related to oblique collision between the Yangzi and Sino-Korean cratons and tectonic evolution from early compressional to late extensional or rifting regimes. Most polymetallic deposits in the Lower Changjiang metallogenic belt are clustered in seven districts where the Yanshanian magmatism is particularly extensive: from west to east, Edong, Jiurui, Anqing–Guichi, Luzhong, Tongling, Ningwu and Ningzhen. Mineralization is characterized by the occurrence of three distinct types of orebodies in individual deposits: orebodies in Yanshanian granitoid intrusions, skarn orebodies at the contact zones between the Yanshanian intrusions and Late Paleozoic–Early Mesozoic sedimentary rocks, and stratabound massive sulfide orebodies in the Late Paleozoic–Early Mesozoic sedimentary strata. The most important host sedimentary strata are the Middle Carboniferous Huanglong Formation, Lower Permian and Lower–Middle Triassic carbonate and evaporite rocks. The intrusion-hosted and skarn orebodies exhibit well-developed zonation in alteration assemblages, metal contents, and isotopic compositions within individual deposits, and apparently formed from hydrothermal activities related to the Yanshanian magmatism. The stratabound massive sulfide orebodies in the Late Paleozoic–Early Mesozoic sedimentary strata have long been suggested to have formed from sedimentary or volcano-sedimentary exhalative processes in shallow marine environments. However, extensive research over the last 40 years failed to produce unequivocal evidence for syngenetic mineralization. On the basis of geological relationships and isotope geochemical characteristics, we propose a carbonate-hosted replacement deposit model for the genesis of these stratabound massive sulfide orebodies and associated skarn orebodies. This model suggests that epigenetic mineralization resulted from interactions between magmatic fluids evolved from the Yanshanian intrusions with carbonate and evaporite wall rocks. Mineralization was an integral but distal part of the larger hydrothermal systems that formed the proximal skarn orebodies at the contact zones and the intrusion-hosted orebodies. The stratabound massive sulfide deposits of the Lower Changjiang metallogenic belt share many features with the well-studied, high-temperature, carbonate-hosted replacement deposits of northern Mexico and western United States, particularly with respect to association with small, shallow granitoid complexes, structural and stratigraphic controls on mineralization, alteration assemblages, geometry of orebodies, metal association, metal zonation and isotopic systematics. 相似文献
4.
苏家铁多金属矿床位于黑龙江省张广才岭成矿带内,受一撮毛碱长花岗岩体及相关花岗斑岩岩体控制。矿体产出于花岗斑岩和大理岩的接触带及层间破裂带内,主要为矽卡岩型铁锌矿体。组成矿体的主要矿石矿物为磁铁矿和闪锌矿; 围岩蚀变类型主要有矽卡岩化、矽化、角岩化、碳酸盐化和绿泥石化,其中矽卡岩化与矿化关系密切,是区内的主要找矿标志。矿床地球化学特征研究表明成矿物质来自壳源岩浆演化和上部热液交代碳酸岩地层,并在矽卡岩带内形成矿化体和矿体。结合成矿地质背景,确定苏家铁多金属矿床为矽卡岩型矿床。 相似文献
5.
赣东南地区火山地质、矿产特征及找矿方向 总被引：1，自引：0，他引：1
赣东南火山岩区主要发育侏罗纪中、晚世中酸性火山碎屑岩－火山熔岩，其中以爆溢相产出的流纹质晶屑凝灰溶岩分布最广；火山构造主要发育破火山口、岩穹、隐爆角砾岩筒等构造，且与成矿关系；与成矿关系密切的次火山岩广泛发育。区内主要矿化类型为斑岩型、（次火山）隐爆层间裂隙带型、蚀变花岗岩型、隐爆角砾岩型，矿床成因均为与火山活动期后次火山（隐爆）活动有关的岩浆期后高－中温热液交代－充填型矿床。同时，矿床类型上具相互穿插性，隐爆层间裂隙带型、隐爆角砾型等矿床类型往往可以看作是斑岩型矿床的延伸；矿床空间分布上往往具有“一体多型”的特征。新矿化类型是赣南中生代火山岩找矿的重要方向。 相似文献
6.
内蒙古黄岗梁锡铁多金属矿床层状夕卡岩的喷流沉积成因 总被引：6，自引：1，他引：6
内蒙古自治区黄岗梁矿床是大兴安岭中南段的一个大型Sn-Fe多金属矿床,燕山期火山侵入岩广泛出露,通过对矿床地球化学特征的系统研究,并结合矿床地质特征,得出的主要研究成果为:①与含微细浸染胶状锡的磁铁矿层共生的层状夕卡岩与海底火山活动关系密切,是一种很具特色的喷流岩;②REE地球化学特征表明,该矿床层状夕卡岩与典型岩浆热液接触交代夕卡岩存在较大差异,而与现代海底热流体和喷流型矿床及其共生的热水沉积岩有较大的相似性,应属热水喷流成因;③层状夕卡岩的碳、氧同位素组成关系可与许多沉积喷流型块状硫化物矿石及其共生的喷流岩相对比,暗示了两者具有相似的形成机理。 相似文献
7.
Qingdong Zeng Yongbin Wang Song Zhang Jianming Liu Kezhang Qin Jinhui Yang Weidong Sun Wenjun Qu 《Resource Geology》2013,63(1):99-109
Mesozoic ore deposits in Zhejiang Province, Southeast China, are divided into the northwestern and southeastern Zhejiang metallogenic belts along the Jiangshan–Shaoxing Fault. The metal ore deposits found in these belts are epithermal Au–Ag deposits, hydrothermal‐vein Ag–Pb–Zn deposits, porphyry–skarn Mo (Fe) deposits, and vein‐type Mo deposits. There is a close spatial–temporal relationship between the Mesozoic ore deposits and Mesozoic volcanic–intrusive complexes. Zircon U–Pb dating of the ore‐related intrusive rocks and molybdenite Re–Os dating from two typical deposits (Tongcun Mo deposit and Zhilingtou Au–Ag deposit) in the two metallogenic belts show the early and late Yanshanian ages for mineralization. SIMS U–Pb data of zircons from the Tongcun Mo deposit and Zhilingtou Au–Ag deposit indicate that the host granitoids crystallized at 169.7 ± 9.7 Ma (2σ) and 113.6 ± 1 Ma (2σ), respectively. Re–Os analysis of six molybdenite samples from the Tongcun Mo deposit yields an isochron age of 163.9 ± 1.9 Ma (2σ). Re–Os analyses of five molybdenite samples from the porphyry Mo orebodies of the Zhilingtou Au‐Ag deposit yield an isochron age of 110.1 ± 1.8 Ma (2σ). Our results suggest that the metal mineralization in the Zhejiang Province, southeast China formed during at least two stages, i.e., Middle Jurassic and Early Cretaceous, coeval with the granitic magmatism. 相似文献
8.
9.
宋文霞 《沉积与特提斯地质》2002,22(3):95-99
拨茅山—牛头山铜矿床的的赋矿岩石为中生代的火成岩系。侵入岩一潜火山岩一火山岩构成完整的侵入—喷发系列。该矿床可分为火山气液—沉积铜矿床和斑岩型铜矿床两种类型。在成矿前期，陆相火山岩在湖底发生火山喷气、火山热泉以及火山热水沉积。潜火山岩的侵入，伴有长期热液循环活动，在张性断裂为主的赋矿空间生成与斑岩有关的各类型矿床。 相似文献
10.
11.
东昆仑祁漫塔格早中生代大陆地壳增生过程中的岩浆活动与成矿作用 总被引：1，自引：0，他引：1
东昆仑祁漫塔格地区位于青藏高原北缘,为典型的大陆边缘增生造山带,经历了漫长的古生代—早中生代增生造山过程,其中以早中生代岩浆活动与成矿作用最为发育。文章系统总结了区内早中生代侵入岩分布及成因,对与其相关矿床地质、成矿流体特征及成矿物质来源进行分析,进一步探讨了祁漫塔格地区早中生代大陆地壳增生过程中的壳幔混合岩浆活动与成矿作用的关联。研究结果认为,中二叠世—早三叠世以俯冲阶段的侧向增生为主,中-晚三叠世以碰撞-后碰撞阶段的垂向增生为主,与成矿有关的岩浆岩主要为中-晚三叠世石英闪长岩、花岗闪长岩、二长花岗岩、正长花岗岩、花岗斑岩等,以I型、A型花岗岩为主,且多见暗色包体,Sr-Nd-Hf同位素组成表明其源于古陆壳物质的重熔,有地幔物质的参与,由地幔底侵古老陆壳,幔源基性岩浆与壳源花岗质岩浆发生不同程度混合作用而形成。与该时期岩浆活动关系密切的主要为斑岩型铜钼矿床、矽卡岩型铁多金属矿床、层控矽卡岩型铅锌矿床、与碱性花岗岩有关稀有金属矿化等。成矿时代集中于248~210 Ma,成矿流体主要来源于岩浆热液,成矿物质具有壳幔混合来源,区内中-晚三叠世大陆垂向增生过程中的壳-幔岩浆混合作用为区域大规模金属成矿提供大量热能、成矿流体及成矿物质。 相似文献
12.
Zhou Taofa Wu Mingan Fan Yu Duan Chao Yuan Feng Zhang Lejun Liu Jun Qian Bing Franco Pirajno David R. Cooke 《Ore Geology Reviews》2011,43(1):154-169
The Middle-Lower Yangtze (Changjiang) River Valley metallogenic belt is located on the northern margin of the Yangtze Craton of eastern China. Most polymetallic deposits in the Changjiang metallogenic belt are clustered in seven districts where magmatism of Mesozoic age (Yanshanian tectono-thermal event) is particularly extensive. From west to east these districts are: E-dong, Jiu-Rui, Anqing-Guichi, Lu-Zong, Tong-Ling, Ning-Wu and Ning-Zhen. World-class iron ore deposits occur in the Lu-Zong and Ning-Wu ore clusters, which are mainly located in continental fault-bound volcanic-sedimentary basins. One of these deposits is the Longqiao iron deposit, discovered in the northern part of the Lu-Zong Basin in 1985. This deposit consists of a single stratabound and stratiform orebody, hosted in sedimentary carbonate rocks of the Triassic Dongma'anshan Formation. A syenite pluton (Longqiao intrusion) is situated below the deposit. The iron ore is massive and disseminated and the ore minerals are mainly magnetite and minor pyrite. Wall rock alteration mostly consists of skarn minerals, such as diopside, garnet, potassic feldspar, quartz, chlorite, phlogopite and anhydrite. Thin sedimentary siderite beds of Triassic age occur as relict laminated ore at the top and the margin of the magnetite orebody. These sideritic laminae are part of Triassic evaporite-bearing carbonate deposits (Dongma'anshan Formation).Sulfur isotopic compositions show that the sulfur in the deposit was derived from a mixture of magmatic hydrothermal fluids and carbonate–evaporite host rocks. Similarly, the C and O isotopic compositions of limestones from the Dongma'anshan Formation indicate that these rocks interacted with magmatic hydrothermal fluids. The O isotopic compositions of the syenitic rocks and minerals from the deposit show that the hydrothermal magnetite and skarn minerals were formed from magmatic fluids. The Pb isotopic compositions of sulfides are similar to those of the Longqiao syenite. Phlogopite coexisting with magnetite in the magnetite ores yielded a plateau age of 130.5 ± 1.1 Ma (2σ), whereas the LA-ICP MS age of the syenite intrusion is 131.1 ± 1.5 Ma, which is slightly older than the age of phlogopite.The Longqiao syenite intrusion may have crystallized from a parental alkaline magma, generated by partial melting of lithospheric mantle, during extensional tectonics. The ore fluids were probably first derived from magma at depth, later emplaced in the sedimentary rocks of the Dongma'anshan Formation, where it interacted with siderite and evaporite-bearing carbonate strata, resulting in the formation of magnetite and skarn minerals. The Longqiao iron deposit is a skarn-type stratabound and stratiform mineral system, genetically and temporally related to the Longqiao syenite intrusion. The Longqiao syenite is part of the widespread Mesozoic intracontinental magmatism (Yanshanian event) in eastern China, which has been linked to lithospheric delamination and asthenospheric upwelling. 相似文献
13.
14.
柴达木盆地南缘祁漫塔格—鄂拉山地区斑岩-矽卡岩矿床地质 总被引：10，自引：3，他引：7
柴达木盆地南缘祁漫塔格-鄂拉山地区发育斑岩-矽卡岩型铜多金属矿床,成矿主元素为Cu、Mo、Pb、Zn,大部分矿床伴生Au、Ag。斑岩型和矽卡岩型矿（化）体共生于同一个矿区之中,是这类矿床的一个重要特点。与成矿有关的侵入体是印支期的中酸性小岩体,它们具有浅成_超浅成和高侵位等特点。斑岩-矽卡岩矿床的成岩年龄和成矿年龄一致,形成于中三叠世至晚三叠世。它们是东昆仑造山带晚碰撞造山阶段壳-幔作用（幔源岩浆底侵-岩浆混合）的产物,与东昆仑地区这一时期的矽卡岩型铁多金属矿床、热液脉状多金属矿床,以及造山型金矿床共同构成了一个矿床成矿系列。 相似文献
15.
红岭(浩布高)铅锌多金属矿床位于我国大兴安岭南段主峰黄岗-甘珠尔庙成矿带的东北端。该地区成矿地质条件优越,是我国重点矿产勘查区之一。前人对红岭铅锌矿的矿床成因、成矿规律做了大量研究,但对基础地质特征研究不够深入,特别是对矿区主要赋矿围岩的岩石类型、矿区蚀变-矿化的类型及空间分布规律等方面的研究相对薄弱,制约了研究区矿床成因研究及勘察找矿的进展。本文通过详细的野外地质观察、室内岩矿相鉴定及扫描电镜/能谱(SEM/EDS)研究发现,矿区内出露的二叠纪地层除大理岩外,其余均为火山岩和火山碎屑岩,未见正常碎屑岩,与已有勘查资料认识不同,且在片理化二叠系晶屑凝灰岩中发现了由黄铜矿和闪锌矿组成的压力影,表明该区二叠系中可能发育同生的铜、锌矿化。矿区内除矽卡岩型矿化外还存在角砾岩型、热液脉型、碳酸盐交代型等多种矿化类型,为该区找矿提供了新思路。 相似文献
16.
The Dongfengnanshan Cu polymetallic deposit is one representative deposit of the Tianbaoshan ore district in the Yanbian area, northeast(NE) China. There occur two types of ore bodies in this deposit, the stratiform ore bodies and veintype ones, controlled by the Early Permian strata and the Late Hercynian diorite intrusion, respectively. Due to the ambiguous genetic type of the stratiform ore bodies, there has been controversy on the relationship between them and veintype ore bodies. To determine the genetic type of stratiform ore bodies, laser ablation inductively coupled plasma mass spectrometry(LA-ICP-MS) in situ trace elements and S–Pb isotope analysis have been carried on the sulfides in the stratiform ore bodies. Compared with that in skarn, Mississippi Valley-type(MVT), and epithermal deposits, sphalerite samples in the stratiform ore bodies of the Dongfengnanshan deposit are significantly enriched in Fe, Mn, and In, while depleted in Ga, Ge, and Cd, which is similar to the sphalerite in volcanic-associated massive sulfide(VMS) deposits. Co/Ni ratio of pyrrhotites in the stratiform ore bodies is similar to that in VMS-type deposits. The concentrations of Zn and Cd of chalcopyrites are similar to those of recrystallized VMS-type deposits. These characteristics also reflect the intermediate ore-forming temperature of the stratiform ore bodies in this deposit. Sulfur isotope compositions of sulfides are similar to those of VMS-type deposits, reflecting that sulfur originated from the Permian Miaoling Formation. Lead isotope compositions indicate mixed-source for lead. Moreover, the comparison of the Dongfengnanshan stratiform ore bodies with some VMStype deposits in China and abroad, on the trace elements and S–Pb isotope characteristics of the sulfides reveals that the stratiform ore bodies of the Dongfengnanshan deposit belong to the VMS-type, and have closely genetic relationship with the early Permian marine volcanic sedimentary rocks. 相似文献
17.
Thin- to medium-bedded, stratiform calc-silicate deposits (banded skarns) are a peculiar, but important, component of the supracrustal successions in the Palaeoproterozoic Bergslagen mining district of central Sweden. They are referred to as ??skarn-banded leptites?? in the literature and are common in areas and at stratigraphic levels that contain iron oxide and base metal sulphide deposits. The stratigraphic hanging wall of the stratabound Ryllshyttan Zn?CPb?CAg + magnetite deposit at Garpenberg, contains approximately 100?C150?m of interbedded aluminous skarn beds and rhyolitic ash-siltstones. The skarn beds are mineralogically variable and dominantly composed of grandite, spessartine, epidote, actinolite, quartz, clinopyroxene, and locally magnetite. Integrated field-mapping, and whole-rock lithogeochemical, microscopic and mineral chemical analyses suggest that the stratiform skarn beds are the products of at least two discrete hydrothermal events and subsequent metamorphism. The first event comprised accumulation in a quiescent subaqueous environment, below wave base, of calcareous and ferruginous sediments rich in Fe, Mn, Ca, and Mg. These chemical sediments were deposited concurrently with rhyolitic ash-silt sedimentation, thus forming a (now metamorphosed) laminated calcareous Fe formation with both a detrital rhyolitic component and rhyolitic siltstone interbeds. Positive Eu-anomalies and negative Ce-anomalies for normalized rare earth element analyses of skarn beds suggest that the iron may have been derived from exhalation of hot and reduced hydrothermal fluids, which upon mixing with more oxidized seawater, precipitated Fe oxides and/or carbonates that settled from suspension to the seafloor. The size of the positive Eu-anomalies of the chemical sediments are modified by the content of rhyolitic volcaniclastic material, which has a negative Eu anomaly, such that positive Eu-anomalies are only observed in skarn beds that possess a minor volcaniclastic component. Subsequently, the calcareous Fe formations were subjected to post-depositional alteration by hydrothermal fluids, locally yielding more manganoan and magnesian assemblages. The Mn-alteration is manifested by lateral gradations from epidote-grandite-clinopyroxene±magnetite rocks into significantly more Mn-rich quartz-spessartine rocks and massive andradite rocks over distances of less than 10?cm within individual skarn beds. Magnesian alteration is manifested by the development of discordant zones of pargasite para-amphibolites and formation of stratiform pargasite rocks texturally similar to the interlaminated grandite-epidote-ferroan diopside rocks. The latter increase in abundance towards the Ryllshyttan deposit and are associated with pre-metamorphic/pre-tectonic K?CMg?CFe±Si alteration (now biotite-phlogopite-garnet-cordierite-pargasite rocks) that is related to base metal mineralization. The zone of Mn- and Mg-altered skarn beds extends beyond the zone of pervasive K?CMg?CFe±Si alteration around Ryllshyttan. This suggests that the skarn bed progenitors, or their sedimentary contacts against rhyolitic ash-siltstones, acted as conduits to outflowing hydrothermal fluids. The chemical and mineralogical imprint, imposed on affected beds by alteration, may serve as indicators of proximity to intense K?CMg?CFe±Si alteration envelopes around other base metal sulphide deposits in Bergslagen. The last recorded event comprised syn-tectonic veining of competent massive andradite skarn beds. The veins contain quartz-albite-epidote-ferroan diopside-actinolite assemblages. 相似文献
18.
青海江里沟钨多金属矿床目前是青海境内规模最大的钨矿床,其规模达中-大型,大地构造位置属秦祁昆复合造山系秦岭造山带西段。本文从江里沟钨多金属矿床的成矿地质背景、矿区地质特征、矿体特征等方面入手,总结矿床控矿因素及矿化富集规律。矿体受岗察复式花岗岩体与围岩接触带控制,矿化围绕岩体具有明显的分带性,自岩体向外形成了斑岩型钼矿化-云英岩型钨矿-矽卡岩型钨铜钼矿-角岩型钨矿-脉状铅锌矿的矿化系列,以矽卡岩型为主要类型。其矿床成因为与晚三叠世江里沟复式花岗岩体晚阶段花岗斑岩和细粒花岗岩的侵入及岩浆后期热液有关的多位一体矿床,为下一步的找矿提供依据。 相似文献
19.
XU Zhaowen LU Xiancai LING Hongfei LU Jianjun JIANG Shoyong NIE Guiping HUANG Shunsheng HUA Ming State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Hankou Roa Nanjing Jiangsu Geological Survey of Jiangsu Province Nanjing Jiangsu 《《地质学报》英文版》2005,79(3):405-413
1 Introduction The region of the middle-lower reach of the Yangtze River is an important mineralized belt of Fe, Cu, Au, S and other elements, with a series of sedimentary-hydrothermal diplogenetic mineral deposits (Xu and Zhu, 1978; Liu et al., 1984; Gu and Xu, 1986; Gu et al., 1993, 2000; Zhai et al., 1992). Some geologists thought that the Carboniferous massive sulfide exhalative sediment was the basis of the late diplogenetic mineralization (Gu and Xu, 1986; Gu et al., 1993, 2000); o… 相似文献
20.
Palladium, Platinum and Gold Concentrations in Fengshan Porphyry Cu–Mo Deposit, Hubei Province, China 总被引：1，自引：0，他引：1
Abstract: The Fengshan porphyry-skarn copper–molybdenum (Cu–Mo) deposit is located in the south-eastern Hubei Province in east China. Cu–Mo mineralization is hosted in the Fengshan granodiorite porphyry stock that intruded the Triassic Daye Formation carbonate rocks in the early Cretaceous (~140 Ma), as well as the contact zone between granodiorite porphyry stock and carbonate rocks, forming the porphyry-type and skarn-type association. The Fengshan granodiorite stock and the immediate country rocks are strongly fractured and intensely altered by hydrothermal fluids. In addition to intense skarn alteration, the prominent alteration types are potassic, phyllic, and propylitic, whereas argillation is less common. Mineralization occurs as veins, stock works, and disseminations, and the main ore minerals are chalcopyrite, pyrite, molybdenite, bornite, and magnetite. The contents of palladium, platinum and gold (Pd, Pt and Au) are determined in nine samples from fresh and mineralized granodiorite and different types of altered rocks. The results show that the Pd content is systematically higher than Pt, which is typical for porphyry ore deposits worldwide. The Pt content ranges from 0.037 to1.765 ppb, and the Pd content ranges between 0.165 and 17.979 ppb. Pd and Pt are more concentrated in porphyry mineralization than skarn mineralization, and have negative correlations with Au. The reconnaissance study presented here confirms the existence of Pd and Pt in the Fengshan porphyry-skarn Cu–Mo deposit. When compared with intracontinent and island arc geotectonic settings, the Pd, Pt, and Au contents in the Fengshan porphyry Cu–Mo deposit in the intracontinent is lower than the continental margin types and island are types. A combination of available data indicates that Pd and Pt were derived from oxidized alkaline magmas generated by the partial melting of an enriched mantle source. 相似文献