The newly discovered Shanzhuang BIF is hosted in the Shancaoyu Formation of the Taishan Group within the Eastern Block,southeastern margin of the North China Craton.The ores can be subdivided into three types in terms...The newly discovered Shanzhuang BIF is hosted in the Shancaoyu Formation of the Taishan Group within the Eastern Block,southeastern margin of the North China Craton.The ores can be subdivided into three types in terms of mineral assemblages,corresponding to three types(Ⅰ,Ⅱ,Ⅲ).The element concentration of the type Ⅰ magnetite is similar to that of the type Ⅱ magnetite,while the type Ⅲ magnetite is similar to that of the schist.In general,magnetite and hemat ite grains from the ores show high concentrations of Mn(1317,1162 ppm),Co(787,1023 ppm),Al(2224,2435 ppm)and Ti(540,300 ppm),Whereas magnetite is depleted in Si(420 ppm)and hematite enriched in Si(1690 ppm).Detailed petrographic and mineral chemical analysis of magnetite,hematite,amphibole/hornblende and pyroxene,reveals that almost all the minerals occur as subhedral-anhedral grains with pits and fractures,and the BIF is recrystallized to metamorphic assemblages of high amphibolite facies.Hornblende is highly enriched in Fe,Mg and Ca,but depleted in K and Na,mostly belonging to magnesiohornblende.In addition,the ratios of Mg/(Mg+Fe^2+),Fe^3+/(Fe^3++Fe^2+),Si/(Si+Ti+Al)and Al/Si are 0.48-0.64,0.17-0.36,0.79-0.88 and 0.14-0.27,respectively.It is suggested that hornblende is neither a typical magmatic origin nor a typical metamorphic.Pyroxene has the characteristics of high Ca and Fe,but low Ti and Al,with end-member components En,Wo and Fs in the ranges of 25.22-28.64 wt%,43.71-46.40 wt%and 24.51-27.62 wt%,respectively,belonging to clinopyroxene,and mostly diopside,might be formed during the prograde metamorphism in the absence of H2 O.The carbonate such as dolomite-ankerite series is probably a precursor mineral of the BIF deposit.Mass mineral chemical and structural characteristics indicate that the Shanzhuang iron deposit has been subjected to varying degrees of oxidized hydrothermal superimposed reformation,metamorphism,and supergenesis after mineralization,during which some elements have been migrated in some degree.展开更多
Black shales are marine sediments with argillaceous, silty and siliceous compositions and high contents of organic materials, disseminated pyrite and uranium. Uraniferous black shale has uranium content of more than 2...Black shales are marine sediments with argillaceous, silty and siliceous compositions and high contents of organic materials, disseminated pyrite and uranium. Uraniferous black shale has uranium content of more than 20 ppm.展开更多
The gold orefield studied is located on the south border of the underthrust-collision zone of the Qinling microplate and the North China microplate in the Indosinian epoch. The main ore deposits localized in the area ...The gold orefield studied is located on the south border of the underthrust-collision zone of the Qinling microplate and the North China microplate in the Indosinian epoch. The main ore deposits localized in the area where the WNW-trending compression-shear type fault of the Indosinian epoch intersected the NE-trending tenso-shear type fault of the Yanshanian epoch. The orebody appeared in a chambered or wedged form. The mineral composition is relatively complex. On the southeastern border of the orefield there have developed intermediate-acid anatectic magmatites of the Mesozoic Era. Three-phase inclusions (Lco2, Vco2 and LNaCl-H2O) comprise over 50%, associated with vapor phase consisting of H2O, CO2, CO, CH4, N2 and H2. The ore-forming fluids can be divided into 2 stages (the early and the late). The samples are projected in the area of mixture of initial magmatic and meteoric water on the δD-δ18O diagram, suggesting two types of mineralization, i.e. the re-equilibrated magmatic-hydrothermal type and the circulating geothermal water type of a meteoric water source. The mineralization occurring in this orefield might be a superimposition of 2 tectono-magmatic activities (the Indosinian and Yanshanian movements). Therefore, it is considered a superimposed B-S type gold orefield.展开更多
个旧锡多金属矿床是驰名中外的特大型矿床,过去认为是燕山晚期"花岗岩岩浆期后气液矿床"。但通过探讨区域上前震旦纪地壳演化、震旦纪—早古生代地壳演化、泥盆纪—三叠纪地壳演化以及侏罗纪—第四纪地壳演化,以及与成矿之间...个旧锡多金属矿床是驰名中外的特大型矿床,过去认为是燕山晚期"花岗岩岩浆期后气液矿床"。但通过探讨区域上前震旦纪地壳演化、震旦纪—早古生代地壳演化、泥盆纪—三叠纪地壳演化以及侏罗纪—第四纪地壳演化,以及与成矿之间的关系,发现个旧矿区至少经历了印支中晚期海底基性火山—沉积成矿、印支中晚期海底喷流热水沉积成矿、燕山晚期花岗岩叠加改造成矿以及喜山期陆相表生沉积成矿作用,厘定了个旧锡矿区的印支中晚期海底基性火山 沉积Sn Cu Zn(Au)矿床系列、印支中晚期海底喷流 沉积Sn Cu Pb Zn矿床系列、燕山晚期花岗岩叠加改造Sn Cu W Be Bi Pb Zn Ag矿床系列、喜山期陆相表生沉积砂矿矿床系列等4大矿床系列及12种矿床类型。展开更多
基金financially supported by the National Natural Science Foundation of China(Grants No.41503038,41140025,41672084,41372086)Special fund for“Taishan scholars”project in Shandong Province,Key R&D Program of Shandong Province(Grant No.2019GSF109101)+2 种基金Key R&D Program of China(Grants No.2016YFC0600105-04,2016YFC0600606)Shandong Provincial Natural Science Foundation(Grant No.ZR2019PD005)Shandong Key Laboratory of Mineralization Geological Processes and Resources Utilization in Metallic Minerals(Grant No.kfkt201809)。
文摘The newly discovered Shanzhuang BIF is hosted in the Shancaoyu Formation of the Taishan Group within the Eastern Block,southeastern margin of the North China Craton.The ores can be subdivided into three types in terms of mineral assemblages,corresponding to three types(Ⅰ,Ⅱ,Ⅲ).The element concentration of the type Ⅰ magnetite is similar to that of the type Ⅱ magnetite,while the type Ⅲ magnetite is similar to that of the schist.In general,magnetite and hemat ite grains from the ores show high concentrations of Mn(1317,1162 ppm),Co(787,1023 ppm),Al(2224,2435 ppm)and Ti(540,300 ppm),Whereas magnetite is depleted in Si(420 ppm)and hematite enriched in Si(1690 ppm).Detailed petrographic and mineral chemical analysis of magnetite,hematite,amphibole/hornblende and pyroxene,reveals that almost all the minerals occur as subhedral-anhedral grains with pits and fractures,and the BIF is recrystallized to metamorphic assemblages of high amphibolite facies.Hornblende is highly enriched in Fe,Mg and Ca,but depleted in K and Na,mostly belonging to magnesiohornblende.In addition,the ratios of Mg/(Mg+Fe^2+),Fe^3+/(Fe^3++Fe^2+),Si/(Si+Ti+Al)and Al/Si are 0.48-0.64,0.17-0.36,0.79-0.88 and 0.14-0.27,respectively.It is suggested that hornblende is neither a typical magmatic origin nor a typical metamorphic.Pyroxene has the characteristics of high Ca and Fe,but low Ti and Al,with end-member components En,Wo and Fs in the ranges of 25.22-28.64 wt%,43.71-46.40 wt%and 24.51-27.62 wt%,respectively,belonging to clinopyroxene,and mostly diopside,might be formed during the prograde metamorphism in the absence of H2 O.The carbonate such as dolomite-ankerite series is probably a precursor mineral of the BIF deposit.Mass mineral chemical and structural characteristics indicate that the Shanzhuang iron deposit has been subjected to varying degrees of oxidized hydrothermal superimposed reformation,metamorphism,and supergenesis after mineralization,during which some elements have been migrated in some degree.
文摘Black shales are marine sediments with argillaceous, silty and siliceous compositions and high contents of organic materials, disseminated pyrite and uranium. Uraniferous black shale has uranium content of more than 20 ppm.
文摘The gold orefield studied is located on the south border of the underthrust-collision zone of the Qinling microplate and the North China microplate in the Indosinian epoch. The main ore deposits localized in the area where the WNW-trending compression-shear type fault of the Indosinian epoch intersected the NE-trending tenso-shear type fault of the Yanshanian epoch. The orebody appeared in a chambered or wedged form. The mineral composition is relatively complex. On the southeastern border of the orefield there have developed intermediate-acid anatectic magmatites of the Mesozoic Era. Three-phase inclusions (Lco2, Vco2 and LNaCl-H2O) comprise over 50%, associated with vapor phase consisting of H2O, CO2, CO, CH4, N2 and H2. The ore-forming fluids can be divided into 2 stages (the early and the late). The samples are projected in the area of mixture of initial magmatic and meteoric water on the δD-δ18O diagram, suggesting two types of mineralization, i.e. the re-equilibrated magmatic-hydrothermal type and the circulating geothermal water type of a meteoric water source. The mineralization occurring in this orefield might be a superimposition of 2 tectono-magmatic activities (the Indosinian and Yanshanian movements). Therefore, it is considered a superimposed B-S type gold orefield.
文摘个旧锡多金属矿床是驰名中外的特大型矿床,过去认为是燕山晚期"花岗岩岩浆期后气液矿床"。但通过探讨区域上前震旦纪地壳演化、震旦纪—早古生代地壳演化、泥盆纪—三叠纪地壳演化以及侏罗纪—第四纪地壳演化,以及与成矿之间的关系,发现个旧矿区至少经历了印支中晚期海底基性火山—沉积成矿、印支中晚期海底喷流热水沉积成矿、燕山晚期花岗岩叠加改造成矿以及喜山期陆相表生沉积成矿作用,厘定了个旧锡矿区的印支中晚期海底基性火山 沉积Sn Cu Zn(Au)矿床系列、印支中晚期海底喷流 沉积Sn Cu Pb Zn矿床系列、燕山晚期花岗岩叠加改造Sn Cu W Be Bi Pb Zn Ag矿床系列、喜山期陆相表生沉积砂矿矿床系列等4大矿床系列及12种矿床类型。
