滇黔交界地区峨眉山玄武岩铜矿的PGE及微量元素特征

为了进一步探讨玄武岩铜矿的成因,文章对滇黔交界地区玄武岩铜矿石的铜、铂族元素及其他微量元素的地球化学特征进行了研究。结果表明：与铜矿化关系密切的有机质对铜的初始富集作用不明显,铜矿化是后生热液成因的,进一步支持了玄武岩为铜矿化的矿源岩、沥青及碳质等有机质的存在只是为自然铜沉淀提供了条件的认识。而且,铜矿石的低U、Th含量为该类铜矿石的铅是正常铅提供了合理的解释。     

滇东北玄武岩相关铜矿类型特征分析

玄武岩中铜矿的含矿岩系是指上二叠统峨眉山玄武岩组(P2e)上部～宣威组(P2x)底部的一套含铜背景值较高、且有明显铜矿化及铜矿层存在的含矿火山地层组合。依据容矿主岩,可分为三种类型:玄武岩型铜矿、玄武岩含碳沉积岩夹层型铜矿及沉积间断面上铝土质泥岩铜矿。     

贵州西南部与玄武岩有关的铜矿特征及找矿前景

近年在贵州峨眉山玄武岩西南部发现若干玄武岩铜矿点,其成矿地质特征与玄武岩北部的贵州黑山坡、云南鲁甸、云南永胜得等玄武岩铜矿有一定区别,前者主要产于玄武岩下部或底部,铜矿多受小尺度断裂构造控制;后者多产于玄武岩上部旋回、受植物层或含沥青质层控制,呈层带型产出。本文通过贵州西南部玄武岩成矿地质特征的研究,进一步丰富了峨眉山玄武岩铜矿研究资料,并揭示了研究区找铜前景。     

贵州西部峨眉山玄武岩铜矿特征及成矿作用

通过对峨眉山玄武岩含铜性及与铜矿的关系研究,提出玄武岩铜矿存在两个阶段成矿作用,即火山活动阶段和后期热液活动阶段成矿。控矿条件有：(1)喷发中心地区火山沉积富铜矿源层;(2)具相当规模的水循环系统;(3)与矿源层有较大接触面的容矿构造。     

峨眉山大火成岩省与玄武岩铜矿--以贵州二叠纪玄武岩分布区为例

贵州晚二叠世玄武岩是峨眉山大火成岩省的组成部分，并位于其东区。全属高钛玄武岩。它是地幔柱边部或消亡期局部熔融产物。产物我省玄武岩中的铜矿床（点），与北美大陆同类铜矿有相似之处，可统称为玄武岩铜矿，属于“与陆相镁铁质喷发岩有关的铜矿床成矿系列”。     

黔西北地区威宁铜厂河玄武岩型铜矿化特征及矿化规律

铜厂河铜矿产于大陆溢流钙碱性玄武岩中,铜矿化主要产于第三喷发旋回中晚期,即第8喷发层(P3em3-8)中上部,赋矿岩石主要为杏仁状玄武岩,矿体呈似层状产出,经详查以估算资源量矿石量约115万t,铜金属量1.1万t,铜品位0.98%,为一小型铜矿床。通过总结铜矿化特征与矿化规律,对我国西南地区广泛分布的同期玄武岩,特别在黔西北地区具有相似成矿地质背景,对其找矿可提供借鉴。     

威宁铜厂河玄武岩铜矿成矿地质特征及成因探讨

研究威宁铜厂河铜矿区玄武岩的岩石类型、常量元素、微量元素及稀土元素地球化学特征,探讨玄武岩铜矿的成矿地质背景、控矿因素、产出特征和成矿规律,系统总结了找矿标志.研究认为,本区玄武岩具大陆拉斑玄武岩特征,铜矿属火山同生热液成矿叠加埋藏变质作用改造形成的玄武岩铜矿.     

峨眉山玄武岩组铜矿化与层位关系研究

根据地球化学急变带控矿的分带性规律,在滇黔边界发现了新类型的铜矿化及工业矿体找矿线索。铜矿化一般赋存在二叠系峨眉山玄武岩组,二者之间难于识别,铜矿物以自然铜和黑铜矿为主,赋存于特定的熔结凝灰岩、火山凝灰角砾岩层位,形成作用与有机质有关,很可能形成一种新的铜矿工业类型。基于野外调研和室内岩矿鉴定,按铜矿化的矿物组合及赋存特点,初步划分为：硅质沥青铜矿化;次生氧化、硫化物铜矿化;团块浸染状自然铜矿化;热液蚀变沸石化型黑铜矿化;凝灰角砾岩型黄铜矿化和碳质、硅化木铜矿化等6种铜矿化类型。这些矿化类型分别与相应的玄武岩组韵律层相对应,其中,沥青质铜矿化类型在区域上分布广泛,沥青广泛充填于熔结凝灰岩的气孔和含矿凝灰岩、碳泥质岩石破碎带中,自然铜、黑铜矿等矿物赋存于硅质沥青岩中,矿化层稳定,找矿标志明显,具有重要的创新性研究意义和找矿价值。     

滇黔交界地区峨眉山玄武岩铜矿化蚀变特征

滇黔交界地区蛾眉山玄武岩铜矿化具层控特征,主要发育于上二叠统蛾眉山玄武岩组第四岩性段下部。矿化主岩为玄武岩流顶部的淬碎玄武质角砾岩和玄武岩流之间的含炭沉积岩;矿石矿物主要为自然铜及其表生氧化产物黑铜矿、赤铜矿、孔雀石等;脉石矿物主要有沥青、炭质物、石英、沸石、方解石、绿帘石等,此外还有少量绿泥石、钠长石、铁阳起石、榍石、辉铜矿、硅孔雀石、铜蓝、褐铁矿等。以玄武岩为主岩的铜矿石典型矿物组合为自然铜 沥青 石英及不含沥青等有机质的自然铜 石英 绿帘石,以含炭沉积岩为主岩的铜矿石典型矿物组合为自然铜 炭质物 沸石 石英( 辉铜矿);原生铜矿化有2个期次：早期铜矿化发生于有机质流体贯人之前,晚期铜矿化发生于有机质流体贯人之后。该类铜矿化的同生火山热液特征不明显,以后生热液矿化为主。淬碎玄武质角砾岩不仅是有机流体的良好储层,也为成矿流体提供了就位空间,是铜矿化层控特征的主要控制因素。有机流体及含碳沉积岩中碳质为成矿物质以自然铜形式沉淀提供了还原条件。     

论玄武岩金矿的地质特征

滇黔桂金三角区内一些产于峨眉山玄武岩组(含底部大厂层)和龙潭组内的金矿,其含矿岩性主要是玄武熔岩、凝灰岩和含凝灰质、碳质的粉砂岩、页岩．一些学者将它们都归入“卡林型金矿”．但因为地幔柱成因的玄武岩,自有其独立的成矿系列,包含Cu、Fe、Mn、Au、Pt、Pd、Co、Pb、Zn、Sb、CaF2、FeS2等多种矿产,在不同地区,其矿化各有侧重．可以看到金的矿集区都在铜的矿集区之南,且以玄武岩喷溢早期(大厂层)更富金,应命名为玄武岩金矿．晚期(龙潭组)更富铜为特色(玄武岩铜矿)．在共同具备含金(P2β2-1)、含铜(P21)有利地层与有利构造区内,发现卡林型金矿后,应着重探索玄武岩金矿,反之亦然．     

Lead isotopic systematics for native copperchalcocite mineralization in basaltic lavas of the Emeishan large igneous province, SW China： Implications for the source of copper

The Emeishan continental flood basalt, which is widespread in Yunnan, Guizhou and Sichuan provinces of Southwest China, is the volcanic product of a Permian mantle plume, and native copper-chalcocite mineralization associated with the basalt is very common in the border area of Yunnan and Guizhou provinces. The mineralization occurred in the tuff intercalation and terrestrial sedimentary rock intercalation which were formed during the main period of basalt eruption. The orebodies are controlled by the stratigraphic position and faults. Metal ore minerals in the ores are mainly native copper, chalcocite and tenorite, with small amounts of chalcopyrite, bomite, pyrite and malachite, and sometimes with large amounts of bitumen, carbon and plant debris. Several decades of ore deposits are distributed in the neighboring areas of the two provinces, while most of them are small-scale deposits or only ore occurrences. By comparing the lead isotopic composition of the ores with that of the wall-rocks, cover and basement rocks of various periods, the source of copper in this type of ore deposits was studied in this paper. The results showed that: (1) The Pb isotopic composition of the ores from ten deposits is absolutely different from that of sili-ceous-argillaceus rocks of the Upper Permian Xuanwei Formation, limestones of the Lower Permian Series and Carboniferous, Cambrian sandstone-shale and recta-sedimentary rock and dolomite from the upper part of the Meso-Proterozoic Kunyang Group, This indicates that ore lead was derived neither from the cover rock nor from the basement rocks; (2) Although the Neo-Proterozoic Siman dolomite and silicalite, and dolomite in the lower part of the Kunyang Group are similar in Pb isotopic composition to the ores, lead and copper contents in these rocks are very low and they have not made great contributions to copper mineralization; (3) The ores have the same Pb iso-topic composition as the basalt, the latter being enriched in copper. These facts indicate that lead and copper were derived from the basalt. According to the regional geological data and the geological-geochemical characteristics of the ore deposits, it is suggested that ore-forming materials were leached out from the basalt. The thickness and buried depth of the basalt and regional tectonic dynamics can affect the formation of large-scale copper deposits. Therefore, exploration for this type of ore deposits should be conducted in the areas from western Yunnan to western Sichuan, where there are developed basalts of great thickness, with extensive tectonic movement and magmatic activity.     

峨眉山玄武岩浆喷发对贵州西部区域成矿贡献研究

早、晚二叠世之间大规模峨眉山玄武岩喷发是峨眉地幔热柱基性岩浆活动的高峰期.峨眉山玄武岩在贵州西部地区广泛分布,它不仅以矿源层形式参与钼、铜、铅、锌、金、锑、汞、铊等以地下水热液成矿作用为主的层控矿床的形成,而且它自身形成火山气液型矿床--玄武岩铜矿及伴生热液型铂、钯等矿化点;再者它是外生矿床--高砷煤、高氟煤、高硫煤、高汞煤形成的主要原因.     

滇东北含铜矿床峨眉山玄武岩组地层学特征

滇东北与玄武岩有关的铜矿床是我国近年来矿床学研究和资源勘查的热点之一。通过对该地区进行的资源勘查和科学专项研究,发现含矿岩系主要由上二叠统峨眉山玄武岩组(P3e)上部(第三岩性段顶部和第四岩性段)和宣威组(P3x)底部地层组成,在这套地层中识别出5个矿化层,对5个矿化层的岩性组成、矿化特征和成矿前景进行全面总结,为该区域进一步开展找矿勘查和评价提供了方向和依据。     

云南锑（金）成矿带划分及有关成矿问题讨论

云南可划分11个锑（金）成矿带（区）。Sb—Au属同一成矿系列（Sb略晚）,二者常相伴产出。滇东坡脚组（D1p）与滇西三合洞组（T3s）,同为锑矿矿源层。滇东南与黔西区玄武岩喷溢早期的大厂层（P3d）、主期玄武岩组（P3β）、晚期龙潭组（P3l）,三者含Sb、Au背景值远高于全球玄武岩,构成统一的Sb—Au矿源层（岩）,在有利构造条件下,产出Sb矿（伴生Au）、Au矿（伴生Sb）或二者共存（广南堂上）,其成因都与幔源玄武岩喷溢作用有关。     

新疆铜矿类型与找矿靶区

在分析研究新疆铜矿类型、地质特征、矿区地质构造及找铜潜力的基础上，对进一步的找铜靶区进行了初步预测．新疆铜矿工作程度总体较低，各构造成矿区和类型都有找铜前景，最具潜力和最有希望找到大型铜矿床的是阿尔泰，东、西天山和西昆仑地区斑岩型、海相火山沉积型、斑岩—夕卡岩复合型、海相沉积热液叠加型与铜镍矿化物型的成矿类型．     

Geological significance of nickeliferous minerals in the Fule Pb–Zn deposit,Yunnan Province,China

The Fule Pb–Zn deposit is located in the Sichuan–Yunnan–Guizhou Province, and it is an important and giant low temperature metallogenic domain in China. In our research area, the Pb–Zn deposits are mainly hosted in the Permian Yangxin Formation and are composed of dolostone and limestone. The distance between the ore bodies and the Permian Emeishan basalt ranged from 50 to 160 m. In this study, the nickel rich minerals, including vaesite, polydymite and millerite, were reported for the first time in the Fule deposit. These minerals occurred as xenomorphic mineral aggregate and were sporadically distributed in the sphalerite–galena–calcite vein, which is the main ore type in the deposit. Our study indicated that the paragenetic sequence of minerals in the Fule deposit is the following order: polydymite?→?vaesite?→?millerite?→?sphalerite?→?galena?→?tetrahedrite (tennantite). The geological occurrence characteristics of those nickeliferous minerals suggested that the Permian Emeishan basalt is a possible barrier layer of Pb–Zn ore-forming fluid, and it is an important source for the Ni and part of the Cu in the deposit. The Sichuan–Yunnan–Guizhou Pb–Zn mineralization province is a world-class production base of Pb and Zn, in which the Permian Emeishan basalt and Pb–Zn deposits have uniformly spatial distribution, but the relationship of mineralization between them is still under debate. This report provides new evidence for understanding the relationship between Pb–Zn mineralization and Permian Emeishan basalt in the Sichuan–Yunnan–Guizhou Pb–Zn mineralization province.     

新疆西昆仑金(铜)矿找矿前景分析

位于塔里木西南缘的木吉－大同一库地金铜成矿带是西昆仑地区重要成矿带,带内金矿主要产于碳质千枚岩、碎屑岩及绢去母石英片岩等岩石中,受韧性剪切带及构造蚀变带控制。铜（金）矿化与华力西期花岗岩类关系较紧密,金铜找矿以海相喷流沉积型铜（金银）矿、斑岩及夕卡岩型铜金矿、构造蚀变岩型金矿及韧性剪切带型金矿为主,根据金铜成矿环境分析,认为该区的金铜找矿潜力巨大。     

反映矿质沉淀环境的造岩元素地球化学异常——地球化学勘查盲矿预测的重要标志

围岩蚀变有一部分是成矿作用的结果。与成矿作用关系密切的围岩蚀变是矿质沉淀之前的早期围岩蚀变,它的矿物组合在化学上能够接受矿石的沉淀。实际上这样的围岩蚀变是矿石沉淀的条件准备,是早期的热水溶液与有利的围岩介质环境相互作用的结果,所以它是有利于矿质沉淀的地球化学环境的综合体现。后期蚀变围岩新的矿物组合是造岩元素重新分配的结果,因此造岩元素的地球化学异常无疑反映了有利于矿质沉淀的地球化学循环和成矿作用。斑岩铜矿和黑矿型矿床分别具有典型的造岩元素地球化学异常模式,其空间分布形态和量的变化与矿化范围及赋矿部位具有密切的对应关系。包体成分的研究、矿质的络合物迁移理论、矿液与围岩间的物质交换以及黄铁矿矿床成矿初期所成的“交代岩柱”等均表明造岩元素控制了成矿组分的迁移、聚集和沉淀。因此造岩元素地球化学异常不仅是矿床地球化学研究的重要内容,且是地球化学找矿评价尤其是找盲矿的重要标志。     

个旧老卡岩体凹陷带岩矿特征与成矿机理分析

对云南个旧矿田的典型控矿地带——老卡岩体凹陷带内的矿化特征、岩相学及矿相学特征和流体包裹体进行分析,进一步研究花岗岩凹陷带的成矿机理。研究认为变玄武岩中普遍发育的金云母化是导致变玄武岩型矿床中锡矿化与金属硫化物伴生的原因之一,凹陷带内带所见的金云母化和绢云母化都与成矿有着密切的关系。花岗岩凹陷带的成矿作用经历了花岗岩侵位、花岗岩叠加改造玄武岩内的"矿胚"、花岗岩蚀变、矿化沉淀这四个过程。