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1.
Most ore-forming characteristics of the Langshan-Zha'ertaishan hydrothermal exhalation belt, which consists of the Dongshengmiao, Huogeqi, Tanyaokou and Jiashengpan large-superlarge Zn-Pb-Cu-Fe sulfide deposits, are most similar to those of Mesoproterozoic SEDEX-type provinces of the world. The characteristics include: (1) All deposits of this type in the belt occur in third-order fault-basins in the Langshan-Zha'ertaishan aulacogen along the northern margin of the North China Platform; (2) these deposits with all their orebodies hosted in the Mesoproterozoic impure dolomite-marble and carbonaceous phyllite (or schists) have an apparent stratabound nature; ores display laminated and banded structures, showing clear depositional features; (3) there is some evidence of syn-sedimentary faulting, which to a certain extent accounts for the temporal and spatial distribution and the size of the orebodies in all deposits and the formation of intrabed conglomerates and breccias; (4) they show lateral and vertical  相似文献   

2.
Most ore-forming characteristics of the Langshan-Zha'ertaishan hydrothermal exhalation belt, which consists of the Dongshengmiao, Huogeqi, Tanyaokou and Jiashengpan large-superlarge Zn-Pb-Cu-Fe sulfide deposits, are most similar to those of Mesoproterozoic SEDEX-type provinces of the world. The characteristics include: (1) All deposits of this type in the belt occur in third-order fault-basins in the Langshan-Zha'ertaishan aulacogen along the northern margin of the North China Platform; (2) these deposits with all their orebodies hosted in the Mesoproterozoic impure dolomite-marble and carbonaceous phyllite (or schists) have an apparent stratabound nature; ores display laminated and banded structures, showing clear depositional features; (3) there is some evidence of syn-sedimentary faulting, which to a certain extent accounts for the temporal and spatial distribution and the size of the orebodies in all deposits and the formation of intrabed conglomerates and breccias; (4) they show lateral and vertical  相似文献   

3.
The Huogeqi orefield located on the northern side of Mt. Langshan, Inner Mongolia occurs in the Middle Proterozoic Langshan Group metamorphic rocks, and the orebodies arc stratiform. In the past twenty years, many Chinese geologists have conducted researches on the Huogeqi Cu-Pb-Zn deposit, but there has been still a controversy on its origin. Some advocate that the deposit is of sedimentary-metamorphic rcworking origin, some hold that it is of sea-floor SEDEX origin, and others have a preference for magmatic superimposition origin. The crux of the controversy is that there is no common understanding about the source of ore-forming materials. In this paper, the Pb isotopic compositions of regional Achaean-Early Proterozoic basement rocks, various types of sedimentary- metamorphic rocks and volcanic rocks in the mining district, Late Proterozoic and Hercynian magmatic rocks arc introduced and compared with the orc-lead composition, so as to constrain the source of the ore lead. The result indicates that （1） sulfides in the ores have homogeneous Pb isotopic compositions, showing a narrow variation range. Their ^206pb/^204pb ratios arc within a range of 17.027- 17.317; ^207Pb/^204pb ratios, 15.451-15.786 and ^208Pb/^204pb ratios, 36.747-37.669; （2） the Pb isotopic compositions of the regional Achaean-Early Proterozoic basement rocks arc characteristic of the old Pb isotopic composition at the early-stage evolution of the Earth, which varies over a wider range, reflecting significant differences in Pb isotopic compositions of the ores. All this indicates that the source of ore lead has no bearing on the basement rocks; （3） the sedimentary-metamorphic rocks in the mining district arc characterized by highly variable and more radiogenic Pb isotopic compositions and their Pb isotopic ratios arc obviously higher than those of ores, demonstrating that ore lead did not result from metamorphic rcworking of these rocks; （4） Pb isotopic compositions of Late Proterozoic diorite-gabbro and Hercynian granite are higher than those of ores. Meanwhile, the Pb isotopic compositions of sulfides in the small-sized strata-penetrating mineralized veinlets formed at later stages arc completely consistent with that of sulfides in stratiform-banded ores, suggesting that these veiniets arc the product of autochthonous rcworking of the stratiform-banded ores during the period of metamorphism and the late magmatic superimposition-mineralization can be excluded; （5） amphibolite, whose protolith is basic volcanic rocks, has the same Pb isotopic compositions as ores, implying that ore lead was derived probably from basic volcanism. So, the source of ore-forming materials for the Huogeqi deposit is like that of the volcanic massive sulfide （VMS） deposits. However, the orebodies do not occur directly within the volcanic rocks, and instead they overlie the volcanic rocks, showing some differences from those typical VMS-type deposits.  相似文献   

4.
The Chagele is a typical Pb-Zn-Cu-Mo deposit located in the western Nyainqentanglha Pb-Zn-Ag-Fe-Cu metallogenic belt (NPMB) that immediately north of the Gangdese porphyry copper belt, Tibet. The deposit contains three ore types: the porphyry (Cu) Mo ores occur as thin veins hosted in the granite porphyry; the skarn (Cu) Pb-Zn type ores are of vein-type or lenticular-type mainly occurring in the external contact zone and interstratified crack zone; and the hydrothermal vein Pb-Zn type ores are controlled by the NNE-striking faults and situated in the structural fractured zones and the up walls of fault zones. The (Cu) Pb-Zn ores consist mainly of galena, sphalerite, chalcopyrite, pyrite, malachite, showing automorphic granular, hypautomorphic to allotriomorphic granular and metasomatic-relict textures, and exhibiting mainly veined, banded, disseminated and massive structures. Hydrothermal alteration includes skarnization, silicification and limonitization. The (Cu) Mo ores consists mainly of chalcopyrite and molybdenite, and minor pyrite. The (Cu) Mo ores are characterized by scaly texture, veinlet and massive structures. It has reserves of 0.38 Mt Pb, 0.6 Mt Zn and 110.1 t Ag, with average grade of 2.08%, 3.29% and 6.07 g/t, respectively, and is considered as a deposit with huge ore-prospecting potential in western of NPMB. However, the ore-forming material and genesis of the Chagele deposit are still not clear. This paper systematically investigated the H, O, S and Pb isotopes of the Chagele deposit and compared it with the other Pb-Zn (Cu-Mo) deposits in the middle-east segment of NPMB. Isotopic geochemical analyses showed that the fluids have δ18O values of -2.2‰ to 2.9‰ and δD values of -189‰ to -157‰, respectively, indicative of mixing between magmatic and meteoric waters. The bimodal distribution of δ34 S values for sulfides (-5.6‰ to -0.8‰, the average: -3.7‰ and 1.1‰ to 2.6‰, the average: 1.8‰) indicated that sulfur of the ores were derived from both wall rocks and magma, while the Cu-Mo orebodies was mainly derived from the granite porphyry. The sulfides have 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb values in ranges of 18.614 to 18.688, 15.657 to 15.747 and 38.988 to 39.269; similarly the granite porphyries have 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb values of 18.663 to 19.058, 15.643 to 15.664, and 39.002 to 39.559, respectively, implying that both of them were originated from the upper crust. The H-O-S-Pb isotopic characteristics of the Chagele deposit are similar to those of the Pb-Zn polymetallic deposits in the mid-east NPMB, suggesting that these deposits have similar ore-forming fluid and material sources. It can be concluded that the Chagele deposit is a typical porphyry type Mo deposit + skarn type-hydrothermal vein type of Cu-Pb-Zn deposit. Moreover, we argue that the mineralization is not only confined to the mid-east NPMB, the western segment of the belt with similar tectonic-magmatism also has high potential of ore mineralization. © 2018, Science Press. All right reserved.  相似文献   

5.
<正>1 Introduction The Dongshengmiao deposit is a super-large Zn-Pb polymetallic sulfide deposit which occurring in the Langshan-Zhaertaaishan metallogenic belt,and located in the western margin of the North China Platform.The ore-bodies of Dongshengmiao deposits are mainly hosted in the second Formation of Langshan Group.There are some studies on the geological characteristics(Peng et al.,2004),geological and  相似文献   

6.
<正>There is a large Mesoproterozoic rift at the northern margin of North China Craton(NCC),and one of China’s most important metallogenic belts,the Langshan-Zhaertai Shan-Bayan Obo mesoproterozoic metallogenic belt is just located in this rift.This metallogenic belt contains some large or ultra-large ore deposits,such as the Bayan Obo iron deposits and ultra-large rare earth deposits,and the large Dongshengmiao Cu-Pb-Zn sulphide deposits.The Zhaertai Group is composed of a set of metamorphic rocks,interbedded with thin ferruginous  相似文献   

7.
In recent years, several large and medium-sized ore deposits have been discovered in the shallow cover of Xuancheng, Anhui Province, indicating that this area has a productive metallogenic geological background and may be a potential prospecting region. Based on systematic investigation, the geological and mineralization characteristics of porphyry Cu-Au deposits and skarn Cu-Mo-W deposits in this region have been summarized. Zircon U-Pb dating (LA-ICP-MS) of the Chating quartz-diorite porphyry and the Kunshan biotite pyroxene diorite yield concordia ages of 145.5 ± 2.1 Ma and 131.8 ± 2.1 Ma, respectively. Meanwhile, the Re-Os dating analyses for molybdenite from the Shizishan and Magushan skarn Cu-Mo deposits yielded 133.81 ± 0.86 Ma and 143.8 ± 1.4 Ma ages, respectively. When viewed in conjunction with previous studies, it is suggested that twostage (the early stage of 145–135 Ma and the late stage of 134–125 Ma) magmatism may have occurred during the Mesozoic in Xuancheng region. Early stage intrusive rocks are distributed along both sides of the Jiangnan deep fault (JDF).The intrusive rocks to the north of the JDF are mainly quartz-diorite porphyry and granodiorite (porphyry) rocks, related to porphyry Cu-Au deposits and skarn-type Cu-Mo-W deposits. These deposits belong to the first stage of the porphyry-skarn copper gold metallogenic belt of the Middle-Lower Yangtze Metallogenic Belt (MLYB), associated with the high potassium calc-alkaline intermediate-acid intrusions. The magmatic and ore-forming materials are mainly derived from the enriched lithospheric mantle. South of the JDF, the Magushan granodiorite is a representative intrusive rock of the first stage I-type granite, which hosts the Magushan Cu-Mo skarn deposit, similar to the W-Mo-Cu skarn deposits in the Eastern Segment of the Jiangnan Uplift Metallogenic Belt (ESJUB). The magmatic and metallogenic materials mainly came from the Neoproterozoic basement, with the possible participation of a small amount of mantle components. The late stage magmatism was dominated by volcanic rocks with a small amount of intrusive rocks, which were consistent with the limited volcanic-intrusive activities in the second stage of the MLYB. The H-O stable isotopes of ore deposits in the region indicate that the ore-forming hydrothermal fluids of the porphyry and skarn deposits were mostly of magmatic water for the ore-forming stage, the percentage of meteoric water obviously increasing during the late ore-forming stage. The ore-forming materials of the deposits are mainly from the deep magma with a few sedimentary wall rocks, according to the stable carbon isotopes of the carbonates in the ore deposits. Additionally, according to previous research, the molybdenite from the MLYB has a higher Re content than that of the ESJUB. The higher content of Re in the molybdenite from the Shizishan deposit is identical to that of MLYB rather than ESJUB, whereas Re characteristics in molybdenite of Magushan deposit are similar to that of ESJUB. The differences in Re characteristics indicate the different deep processes and ore-forming material sources (mainly mantle composition for the former and crustal materials for the latter) of these ore deposits on opposite sides of the JDF.  相似文献   

8.
The Lannigou deposit is a large-sized sedimentary rock-hosted disseminated gold （SRHDG） deposit located in the Youjiang Basin. It is hosted by the Middle Triassic turbidite. Wall rock alterations, including silicification, pyritization, arsenopyritization, carbonatization and argillization, commonly occur along fractures. PGE study demonstrates that either Permian basalts or Triassic ultrabasic intrnsives are unlikely to be the main source of gold mineralization. Coupled with the lack of other nmgmatic activity in the vicinity of the mining area, an amagmatic origin is proposed. Organic matter compositions and GC-MS analysis of the ores and host rocks show that the organics in the ores and the host rocks have a common source; the organic matter in the ores was mainly indigenous. The positive correlation between S2 and Au contents, along with the common occurrence of organic inclusions, suggest involvement of organic matter in the ore-forming process in terms of promoting Au leaching from the source rocks, making colloidal Au migration possible, as well as hydrocarbon reduction of sulphate. Geological and geochemical characteristics of the Lannigou deposit suggest that it was formed through circulation of meteoric water and probably less importantly organic bearing formation water driven by high geothermal gradient caused by late Yanshanian extension, which leached Au from the source bed, and then migrated as Au-bisnlfides and colloidal Au, culminating in deposition by reduction-adsorption and surface complexation of gold onto the growth surface of arsenlan pyrite.  相似文献   

9.
The Katelixi Cu-Zn deposit is a marine volcanic rock-type copper deposit discovered for the first time in the Tokuzidaban Group in eastern Kunlun Mountains area. It is hosted in the Lower Carboniferous Tokuzidaban Group volcanic strata. The orebodies are obviously controlled by the strata and their ore-bearing rocks are a suite of greyish-green mafic tuffs, generally parallel-stratiform, stratoid and lenticular in form, occurring in limestone as well as in the contact between limestone and carbon-bearing siltstone. This ore deposit possesses distinct characteristics of marine volcanic rock sedimentaion. The geological, petrochemical and REE characteristics of its occurrence pro-vide strong evidence suggesting that this deposit is of marine volcanic rock sedimention origin, basically identical to those of some typical marine volcanic rock-type copper deposits in Xinjiang and other parts of China. Marine vol-canic rocks are well developed in the Lower Carboniferous Tokuzidaban strata in eastern Kunlun Mountains area. In addition to this deposit, we have also found a number of copper polymetallic ore deposits or occurrences in associa-tion with marine volcanc activities in many places where there is a good metallogenic prospect. A breakthrough in the understanding of ore prospecting and genesis has not only filled up the gap in prospecting this type of ore depos-its in this area, but also is of great significance in directing exploration of this type of ore deposits in this area.  相似文献   

10.
The ductile shear zone-type gold deposit is a kind that both the ore-forming mechanism and ore-controlling factors are closely related to the ductile shear zone and its evolution. Ductile shear zone develops in Beishan area, Gansu of Northwest China, and develops especially well in the south belt. The controls of the ductile shear zone on gold deposits are as follows. (1) The regional distribution of gold deposits (and gold spots) is controlled by the ductile shear zone. (2) The ductile-brittle shear zone is formed in the evolution process of ductile shear zone and both are only ore-bearing structures and con- trol the shape, attitude, scale, and distribution of mineralization zones and ore-bodies. (3) Com- presso-shear ductile deformation results in that the main kind of gold mineralization is altered mylonite type and the main alteralization is metasomatic. (4) Ore-bearing fracture systems are mainly P-type ones, some D-type and R-type ones, but only individual R’-type and T-type ones. (5) Dynamic differen- tiation and dynamic metamorphic hydrothermal solution resulting from ductile deformation is one of the sources of ore-forming fluid of gold mineralization, and this is identical with that ore-forming ma- terials are mainly from metamorphic rocks, and ore-forming fluid is mainly composed of metamorphic water, and with the fluid inclusion and geo-chemical characteristics of the deposit. (6) There is a nega- tive correlation between the gold abundance and susceptibility anisotropy (P) of the altered mylonite samples from the deposit, which shows that the gold mineralization is slightly later than the structural deformation. All above further expound the ore-forming model of the ductile shear zone type of gold deposits.  相似文献   

11.
内蒙古狼山—渣尔泰山中元古代被动陆缘热水喷流成矿特征   总被引：22，自引：1，他引：21  
彭润民  翟裕生 《地学前缘》2004,11(1):257-268
狼山—渣尔泰山中元古代被动陆缘产有东升庙、炭窑口、霍各乞和甲生盘等热水喷流沉积矿床 ,与世界中元古代的SEDEX型矿集区有许多相似之处 :①矿床的产出受华北古陆北缘裂陷槽内三级断陷盆地控制 ;②各大矿床都具有鲜明的层控特征 ,所有矿体总体呈层产在中元古界的白云石大理岩、碳质千枚岩 (或片岩 )中 ;③矿石具有细纹层状、条带状构造 ,喷流沉积成矿特征十分明显 ;④成矿过程中伴有明显的同生断裂活动 ,它在一定程度上控制了矿体的空间分布及其组合 ;但不同矿床同生断裂活动的强度、时限、规模都不同 ,从而导致不同矿床在相同含矿岩组中矿体产出的先后顺序不同和大量层间砾岩与同生角砾状矿石的形成 ;⑤厚大Zn ,Pb ,Cu复合矿体具有明显的分带性 ,自下至上 ,Cu/ (Zn +Pb +Cu)比值由高→低 ;⑥重晶石层发育 ,多与黄铁矿层互层状产出 ,也有与闪锌矿层互层 ,但与世界典型SEDEX型矿床又有重要差别。成矿期间火山活动明显 ,在霍各乞、东升庙、炭窑口矿床惟一容矿的狼山群第二岩组中先后发现了具有变余斑状或聚斑状结构、变余杏仁构造的基性火山岩、钠质“双峰式”火山岩和钾质“双峰式”海相火山岩及凝灰岩夹层。结合①各种硫化物的铅同位素主要分布在地幔和下地壳铅演化曲线附近 ;②部分黄铁矿的Co/Ni值远  相似文献   

12.
彭润民  王建平 《地学前缘》2020,27(2):420-441
狼山-渣尔泰山是华北克拉通北缘西段元古宙伸展构造体制下被动陆缘的重要热水喷流成矿带,内产东升庙、炭窑口、霍各乞、甲生盘等大型-超大型矿床,其含矿建造是元古宇渣尔泰山群。该成矿带的主体在狼山山脉主峰地区,产有东升庙、炭窑口、霍各乞三大矿床。自2010年在狼山西南原渣尔泰山群阿古鲁沟组地层中发现新元古代酸性火山岩(锆石年龄816~805 Ma)以来,其东部狼山主峰地区的渣尔泰山群及产在其中的炭窑口、东升庙、霍各乞矿床是否也都可以归于新元古代形成是需要进一步研究的重要科学问题。本文依据的事实有:(1)狼山西南新元古界的碎屑锆石最小年龄为1 155 Ma与碳酸盐岩是方解石大理岩;(2)炭窑口矿区渣尔泰山群顶部刘鸿湾组地层的碎屑锆石年龄的两个年龄峰值分别为1 862~1 762 Ma(最小年龄为1 732 Ma)和2 448 Ma,所含碳酸盐岩全部是白云石大理岩类;(3)狼山北侧狼山群含矿岩组中发现年龄为887 Ma±的新元古代基性火山岩; (4)霍各乞矿床含重晶石与微晶长石的硅质层发育,多与黄铁矿层互层状产出,也有与闪锌矿+磁黄铁矿及方铅矿层互层,激光原位分析得到的黄铁矿、方铅矿、闪锌矿和磁黄铁矿的δ34S为17.60‰~21.97‰,显示喷流成矿的硫同位素组成特征。根据以上事实可以确认:(1)狼山西南含酸性火山岩与方解石大理岩的前寒武纪地层是与狼山南侧炭窑口矿区含白云石大理岩的渣尔泰山群在不同盆地中沉积而成;(2)狼山南侧是中元古代裂谷带,产有以炭窑口、东升庙矿床为代表的中元古代喷流-沉积成矿系统;(3)狼山北侧是新元古代裂谷带,产有以霍各乞矿田为代表的新元古代热水喷流成矿系统。产在新元古代狼山群中的霍各乞矿是介于SEDEX型与VMS型之间、但靠近SEDEX型一侧的热水喷流-沉积矿床。  相似文献   

13.
彭润民  王志刚 《地球科学》2000,25(4):404-409
东升庙Zn -Pb -Cu矿床和甲生盘Zn -Pb矿床具有鲜明的层控特征, 前者产在中元古界狼山群二组中, 后者则局限在中元古界渣尔泰山群阿古鲁沟组第二岩段内.二者产出层位相当, 根据(1) 含矿地层有岩相(性) 的突变; (2) 含矿岩段地层厚度顺走向和倾向变化性大、厚度突变现象明显, 并存在层间砾岩和滑塌角砾岩, 角砾成分为大小不一的白云石大理岩块、碳质千枚岩、石英团块、凝灰岩块、变粒岩块、变质火山岩碎块、黑云母片岩碎块; (3) 矿体总体呈层产出, 但有一些Zn -Pb -Cu矿体突然变薄, 甚至消失, 形成鱼头状矿体, 且发育角砾状矿石, 角砾成分与层间砾岩的相同, 且还含Pb -Zn矿石或Py矿石角砾; (4) 火山岩或凝灰岩夹层顺同生断裂带分布, 确认其唯一容矿岩组形成过程中有明显的同生断裂活动.同生断裂系统是含矿热水和火山熔浆进入沉积盆地的通道, 是两大矿床形成的有利因素, 但其活动频率、规模与持续时间的差异, 也造成不同的矿床规模和矿体分布.东升庙矿床同生断裂活动时限相对长、矿床规模大、矿种多.甲生盘矿床同生断裂活动时间短, 矿床规模为大型.   相似文献   

14.
INTRODUCTIONThe L angshan- Zhaertai metallogenic belt is a typicalSEDEX belt of the Mesoproterozoic passive continental m ar-gins in the west section of the northern margin of the NorthChina platform(Zhai et al.,1997) (Fig.1) .The ore- form inggeological setting,the division and correlation of the host suc-cession,the geological features of typical ore deposits andtheir genesis of the belt have been described in references(Zhai et al.,1997;Wang and Zhao,1994;Wang et al.,1992 ;L i et…  相似文献   

15.
位于甘肃北山瓜州县境内的花牛山银铅锌矿是北山地区唯一的喷流(气)沉积型块状硫化物矿床,它赋存于一套浅变质细碎屑岩或中基性火山岩夹碎屑岩-碳酸盐岩建造中。关于该矿床的成矿时代,因无确切的同位素年代学和化石证据,争议较大。对花牛山银铅锌矿三矿区铅锌矿体的赋矿围岩玄武岩样品中的锆石进行了LA-ICP-MS法U-Pb定年研究,获得了207Pb/206Pb年龄1071Ma±5Ma,表明花牛山地区中基性火山喷溢活动发生在晚蓟县世。进而揭示花牛山银铅锌矿床是蓟县纪末期强烈拉张构造环境下,与海底火山喷溢活动相伴随的热液活动的产物。它与北山红山铁矿和东天山彩霞山,北祁连山西段石硐沟,华北地块西北缘东升庙、炭窑口、霍各乞等层控铅锌多金属矿床具可对比性,蓟县纪末期是北山地区一个重要的成矿时期。  相似文献   

16.
华北地台北缘西段主要成矿系统分析   总被引：12，自引：0，他引：12       下载免费PDF全文
肖荣阁  彭润民 《地球科学》2000,25(4):362-368
研究了华北地台北缘地质演化、构造分区, 从南到北依次为乌拉山-色尔腾山-大青山陆内隆起区、东升庙-渣尔泰山陆内裂陷区、狼山-石哈河陆缘隆起区、霍各乞-白云鄂博陆缘裂陷区、白乃庙-白银都西隆起裂陷带、温都尔庙-爱力格庙裂陷带、苏左旗-锡林浩特槽内隆起区.分析了陆缘基底建造和裂谷沉积建造, 划分出裂谷裂陷期和沉降期沉积.研究了成矿系统, 以成矿物质来源的同一性和继承性划分出3个成矿系统: (1) 变质岩金矿成矿系统, 以绿岩建造为物源基础, 有多种矿床类型组合, 主要产于古陆隆起带的变质岩区. (2) 海相火山细碧岩及喷流沉积成矿系统, 主要产于裂谷裂陷期形成的火山岩建造中, 与火山活动岩浆同期的热水喷流有关, 有铜、铅、锌多金属矿床. (3) 碱性-碳酸岩及喷流叠生成矿系统, 产于白云鄂博裂谷早期碱性-碳酸岩火山岩中, 其中伴随高温硅钾热水喷流沉积, 形成稀有-稀土-铁叠生矿床.主、东矿床新生代以来经受了强烈风化剥蚀, 并有冲积富集现象.   相似文献   

17.
The Yinshan deposit in the Jiangnan tectonic belt in South China consists of Pb‐Zn‐Ag and Cu‐Au ore bodies. This deposit contains approximately 83 Mt of the Cu‐Au ores at 0.52% Cu and 0.8 g/t Au, and 84 Mt of the Pb‐Zn‐Ag ores at 1.25% Pb, 1.02% Zn and 33.3 g/t Ag. It is hosted by low‐grade metamorphosed sedimentary rocks and mafic volcanic rocks of the lower Mesoproterozoic Shuangqiaoshan Group, and continental volcanic rocks of the Jurassic Erhuling Group and dacitic subvolcanic rocks. The ore bodies mainly consist of veinlets of sulfide minerals and sulfide‐disseminated rocks, which are divided into Cu‐Au and Pb‐Zn‐Ag ore bodies. The Cu‐Au ore bodies occur in the area close to a dacite porphyry stock (No. 3 stock), whereas Pb‐Zn‐Ag bodies occur in areas distal from the No. 3 stock. Muscovite is the main alteration mineral associated with the Cu‐Au ore bodies, and muscovite and chlorite are associated with the Pb‐Zn‐Ag ores. A zircon sensitive high‐resolution ion microprobe U‐Pb age from the No. 3 dacite stock suggests it was emplaced in Early Jurassic. Three 40Ar‐39Ar incremental‐heating mineral ages from muscovite, which are related to Cu‐Au and Pb‐Zn‐Ag mineralization, yielded 179–175 Ma. These muscovite ages indicate that Cu‐Au mineralization occurred at 178.2±1.4 Ma (2σ), and Pb‐Zn‐Ag mineralization at 175.4±1.2 Ma (2σ) and 175.3±1.1 Ma (2σ), which supports a restricted period for the mineralization. The Early Jurassic ages for the mineralization at Yinshan are similar to that of the porphyry Cu mineralization at Dexing in Jiangnan tectonic belt, and suggest that the polymetallic mineralization occurred in a regional transcompressional tectonic regime.  相似文献   

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