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1.
辽河油田稠油中贵金属分布和赋存状态研究   总被引:1,自引:0,他引:1  
以辽河油田稠油为研究对象,通过原子吸收光谱、实沸点蒸馏等手段,研究了辽河油田稠油中Au、Ag、Pt和Pb等贵金属在不同馏分中的分布特征.结果表明,经过实沸点蒸馏后,贵金属不同沸程温度的原油馏分中含量和分布存在很大差异,Au、Ag、Pt、Pd主要集中在渣油馏分中,在沸点》508℃的渣油馏分中Au、Ag、Pt、Pd的比例分别是93.4%、76.9%、73.4%和68.0%;采用选择性萃取的方法对金在稠油中的存在形态的初步研究发现,金在稠油中主要以有机配合物和少量无机配合物形式存在.  相似文献   

2.
金矿区某些植物中Au、Ag、Cu元素的富集及其与土壤的关系   总被引:3,自引:0,他引:3  
研究Au、Ag、Cu元素在招远金矿区8种植物叶中的富集系数(BAC)后发现,元素Cu在泡桐叶中的富集系数较大,Ag在麻栎叶中富集系数较大,而Au在8种植物叶中的富集系数差异较小.回归分析表明,元素Ag和Au在赤松叶与土壤中的相关性良好,均遵守植物选择性吸收和质量作用定律.可用测量植物叶中的Au及伴生元素含量的方法作为勘探金矿的辅助手段.  相似文献   

3.
太行山区土岭、石湖金矿区地球化学及其找矿标志   总被引:5,自引:0,他引:5  
本文讨论了土岭、石湖金矿区与成矿有关的地质体的地球化学特征及其找矿标志。认为该矿区成矿物质—Au具有多源性;As、Sb、Ag、Au、Cu、Pb、Zn、Co、Ni为找矿指示元素;Hg是远程指示元素,而Au则是直接指示元素。指示元素的轴向分带序列为:As—Ag—Sb—Cu—Zn—Au—Pb—Ni—Co,并以此建立了预测矿体埋藏深度关系式:H=38.790As/Co+442.842 LnH=0.0923Ln[(As.Ag.Sb)/(Au.Co.Ni)]+6.3116  相似文献   

4.
西藏谢通门县雄村铜金矿的成矿与含眼球状石英斑晶的角闪石英闪长玢岩有关,并至少受3个玢岩岩枝控制。主成矿元素为Cu,伴生元素为Au、Ag、Zn、Pb,其他微量元素Mo、As、Ba、Bi、Cd、Co、Mn、Ni、Sb含量较高。元素在垂向上具有分带特征,即从矿体中心向外可依次划分为Cu、Au、Ag、As、Sb、(Bi)→Co、Ni→Mo→Mn→Ba→Pb、Zn、Cd、Bi、(Sb),上述元素的异常和组合是寻找和评价该类矿床的重要地球化学标志。矿床的形成经历了早期Cu—Au—Ag成矿和晚期Zn—Pb—Cu—Au—Ag成矿两个阶段:早期成矿阶段形成了Cu—Au—Ag主矿体,晚期叠加Zn—Pb—Cu—Au—Ag矿化。Cu与Au、Ag呈显著的正相关,Cu主要呈独立矿物黄铜矿产出,Au、Ag主要赋存于黄铜矿中。矿石的K/Na值为6.9、Rb/Sr值为0.8,显示出矿床矿富K、Sr和贫Na、Rb的成矿环境;而Au(平均品位0.6×10-6)0.4×10-6、Au(0.6×10-6)/Cu(0.4%)1和n(Cu)/n(Au)(为20678)40000以及Mo(19.7×10-6),说明该矿床富金而贫钼。矿床所处的大地构造位置,成矿与偏中性的斑岩有关,元素组合特征,异常元素在垂向上的分带特征,主成矿阶段的Cu—Au—Ag矿化和晚期叠加的Zn—Pb—Cu—Au—Ag矿化,富Cu、Au、Ag和贫Mo的成矿元素组合及富K、Sr和贫Na、Rb的成矿环境,均表明矿床具有产于岛弧或类似岛弧环境的斑岩型铜金矿床的特征且叠加斑岩成矿系统晚期呈脉状产出的浅成低温热液型Zn—Pb—Cu—Au—Ag矿化。  相似文献   

5.
汪国栋 《地质与勘探》1990,26(11):17-21
综合找矿、综合评价工作应建立在成矿系列理论基础上,针对不同共(伴)生矿产、尤其Au、Ag等稀贵金属矿的特征,改进不适当的工作方法,防止某些重要Au、Ag矿或共生矿的漏查.  相似文献   

6.
烧锅营子金矿床的黄铁矿形成于早、中、晚3期,是主要的矿石矿物和载金矿物,其中以中期黄铁矿为最主要的载金者.黄铁矿的化学成分为:TFe43.34%~45.52%,S46.58%~48.86%,与标准黄铁矿相比显示亏铁、亏硫特点.黄铁矿内含丰富的微量元素,有Au、Ag、As、Sb、Bi、Cu、Zn、Pb、Co、Ni、W、Mo、Se等.其中Au、Ag、Cu、Pb、Zn、Bi含量较高,而As、Sb低,Se极低.其Au/Ag(多大于0.5)、(Cu+Pb+Zn)/(Co+Ni+As)(4.26)、Co/Ni(>> 1)比值表明其属中温岩浆热液矿床.  相似文献   

7.
浅成低温热液金银多金属矿床矿化分带及找矿标志   总被引:3,自引:0,他引:3  
自20世纪70年代环太平洋地区发现大批浅成低温热液型矿床以来,浅成低温热液矿床业已成为贵金属矿床和Cu、Pb、Zn等有色金属矿床的重要工业类型。文章依据主要工业组分对我国浅成低温热液Au、Ag多金属矿床进行了分类,并讨论了成矿系列及矿化分带特征,即按成矿深度浅成低温热液Au、Ag多金属矿床自下而上可分为:Au-Cu/Cu-Au矿床;Au/Au(Ag)矿床;Au-Ag矿床;Ag/Ag多金属矿床;Pb-Zn-Ag矿床。同时,根据我国浅成低温热液Au、Ag多金属矿床特征尝试性提出了浅成低温热液型银矿床的成矿规律与找矿标志。  相似文献   

8.
归来庄金矿床w(Au)/w(Ag)异常的地质统计学研究   总被引:7,自引:1,他引:6       下载免费PDF全文
肖斌  赵鹏大 《地球科学》2000,25(1):79-82
w (Au) /w (Ag) 比值在金矿床评价方面是一个重要的标志, 也可以提供金矿成因的重要信息.对归来庄金矿床的w (Au) /w (Ag) 异常进行地质统计学研究, 利用指示克立格法研究w (Au) /w (Ag) 的分布规律, 查明Au的赋存部位, 并对该区今后工作提出建议.   相似文献   

9.
不同石英脉型金银矿床中含矿石英脉的红外光谱对比   总被引:1,自引:1,他引:0  
为了探讨红外光谱方法评价石英脉型金银矿床的有效性,选择内蒙、吉林、山东等地的石英脉型金银矿床,对其含矿石英进行了红外光谱分析.根据石英包体片中H2O和CO2的吸光度值A1和A2与石英中Au、Ag的含量关系得出:在同一矿床中A1和A2与Au、Ag的含量呈正相关关系;但不同矿床的石英A1、A2与Au、Ag含量总体上无相关性.利用红外光谱方法评价石英脉含矿性的优越性在于避免了直接测金,而消除了金的测不准性对评价结果的影响.同时,该方法有其局限性,即不同矿床不能采用同一评价标准,只适用于就矿找矿.  相似文献   

10.
采用生物氧化技术和化学方法,利用堆浸工艺分步提取,对含Au 140~150 g/t、Ag 900~1 000 g/t、B i 9.0%~10.0%、Cu14%~17%的多金属浮选金精矿的综合回收工艺进行了研究。经小型搅拌试验,确定了生物氧化浸铜—氰化浸金、NaC l-FeC l3-HC l体系(氯盐法)浸出铋和银的技术方法。通过柱浸试验,研究了利用该方法分步浸取Au、Ag、Cu和B i在堆浸工艺中的可行性。在10 t精矿的扩大试验验中,验证了柱浸试验所取得的工艺指标和参数。试验中掺入骨架材料,解决了精矿在堆浸中的渗透问题;生物氧化过程中,菌种在含高浓度铜离子浸出液中反复驯化,对铜的耐受力提高到30 g/L;在NaC l-FeC l3-HC l体系浸出B i和Ag时,用H2O2将浸出液中的Fe2+氧化成Fe3+,使浸出液能循环使用,且B i和Ag同时浸出。Au、Ag、Cu和B i的最终浸出率分别为92.98%、65.09%、45.33%和53.49%。  相似文献   

11.
Prediction and search for gold deposits in the east of the Siberian Platform are problematic because the study area is overlain by a thick cover of MZ-KZ deposits. Search for gold deposits by the largest geological institutions using conventional methods have not yielded positive results, because the main attention was focused on the discovery of ancient gold-bearing conglomerates of the Witwatersrand type and on the evaluation of the gold ore potential of basic magmatism. Typomorphism of placer gold bears huge information about the genesis of native gold, both its primary endogenous origin and its exogenous transformation, which makes it possible to identify the formation type of mineralization, increases the reliability of the prediction of gold deposits, and ensures their purposeful search in the platform areas. The revealed indicative features of placer gold made it possible to substantiate the formation of the gold ore sources of Precambrian low-sulfide gold-quartz, gold-iron-quartzite, porphyry gold-copper, and gold-PGE mineralization and Mesozoic gold-silver, gold-rare-metal, and gold-sulfide-quartz mineralization in the east of the Siberian Platform. We have established that high-fineness placer gold with microinclusions of pyrite, arsenopyrite, quartz, and carbonates with recrystallized structures and lines of plastic deformation is specific to the ore sources of low-sulfide gold-quartz mineralization. A high content of Cu (up to 4%) in flaky high-fineness gold is one of indicators of porphyry gold-copper mineralization. The angular shape of gold grains, the fine fraction and high fineness of gold, its completely recrystallized and regrown internal structure, and the permanent presence of Fe, Bi, and Cu microimpurities and hematite, ilmenite, and corundum microinclusions are typical of gold-iron-quartzite mineralization. Flaky and laminated high-fineness gold particles with steady Pt, Pd, and Ni impurities and Pt-mineral phases and Au-Pt intergrowths in them testify to the ore sources of gold-PGE mineralization. Laminated and cloddy gold fractions of > 0.25-2.0 mm, the medium and low fineness of gold, its single-crystal or, sometimes, porous internal structure, the wide range of microimpurities (Pb, Zn, As, Sb, Cu, Te, etc.), and microinclusions of native Ag, adularia, Sr-barite, and calcite are indicators of gold-silver mineralization. Laminated, dendritic, and cloddy-angular gold grains, wide variation in gold fineness (307-950‰), and the presence of microinclusions of native bismuth, maldonite, arsenopyrite, and silver tellurides are indicative of gold-rare-metal mineralization. Laminated and cloddy gold grains, their size varying from dust to > 0.25 mm, their mono- and coarse-grained internal structure, wide variation in gold fineness (600-900‰), and the presence of Hg microimpurities (up to 6% and more) and microinclusions of quartz, calcite, pyrite, arsenopyrite, tellurides, selenides, and REE phosphates point to gold-sulfide-quartz mineralization. The established placer gold indicators of the particular formation types of ore sources in the east of the Siberian Platform made it possible to predict Precambrian gold deposits with low-sulfide-gold-quartz mineralization similar to the Kirkland Lake and Porcupine mines and gold deposits with Mesozoic gold-silver mineralization similar to the Cripple Creek mine. The developed criteria for determining the types of mineralization by indicative features of placer gold give an insight into the ore genesis and can be successfully applied to prediction and search for gold deposits and to evaluation of their gold resources.  相似文献   

12.
胶东地区-1000 m以下深部找矿的重大突破,使得探明储量已达5000多t,成为探讨深部金的赋存状态及成矿作用的天然实验室。招贤金矿为焦家成矿带近年深部找矿重大突破之一,矿体主要产于-1260 m以深的晚侏罗世二长花岗岩中,受控于焦家断裂。金属矿物主要为黄铁矿、黄铜矿和银金矿等,脉石矿物包括石英、绢云母、方解石、钾长石等。围岩蚀变以钾长石化、硅化、黄铁绢英岩化、碳酸盐化为主。金矿物以自然金和银金矿为主,呈裂隙金或包体金分布于黄铁矿中,少数不可见金呈晶隙金分布于黄铁矿等矿物中。其中,黄铁矿w(S)=52.227%~54.915%、w(Fe)=44.749%~47.134%,原子个数比S/Fe=1.99~2.11,化学式FeS1.99~FeS2.11;黄铜矿w(S)=34.282%~35.140%、w(Fe)=29.263%~30.268%,w(Cu)=33.130%~34.114%,化学式Cu0.96FeS2.01~Cu1.01FeS2.10,平均化学式为C...  相似文献   

13.
Between 1978 and 2009, approximately 430,000 oz of placer gold were obtained from the Indian River and Black Hills Creek, which equates to roughly 20% of the production for the entire Yukon Territory during that period. The area is unglaciated, exposure is poor, and there are few known lode gold occurrences present. The technique of microchemical characterization of placer gold grains has been applied to illuminate the style(s) of source mineralization and their relationship to placer gold from the Klondike gold district immediately to the north. A total of 2,613 placer gold grains from 22 localities were characterised in terms of the Au, Ag, Cu, and Hg content of their alloy and associated suite of opaque mineral inclusions. A combination of alloy and inclusion mineralogy was used to define gold signatures which augmented the previous classification of orogenic gold in the Klondike. Gold type 3b (8–25% Ag) is the main component of the placers in lower Dominion Creek but is augmented and eventually replaced by type 3a gold (10–40% Ag) in placers in the main Indian River valley, probably through erosion of gold-bearing veins in the valley floor. Type 4 gold exhibits highly variable Ag which may contain Hg to a maximum of 11 wt.%. This gold type also hosts a distinctive inclusion assemblage of complex polymetallic sulphides, tellurides, sulfotellurides, and sulfosalts and has previously been ascribed to local low sulfidation epithermal mineralization. Placer gold in drainages radiating from Eureka Dome exhibits various proportions of types 3 and 4 gold depending on location, but type 3 gold forms the major component in Black Hills Creek and northerly flowing tributaries of the Indian River with the exception of Eureka and Montana creeks. Type 5 gold is found only in placers in the middle and lower Indian River. It is distinguished by slightly elevated (0.05–0.17%) Cu in the gold alloy, together with low (5–9%) Ag contents. Inclusions of Bi minerals, Cr-bearing magnetite and molybdenite within type 5 gold suggest derivation from an intrusion-related source. Candidates for such a source include undiscovered lode occurrences associated with Cretaceous age intrusions to the south of the Indian River, or deformed Cu-Au (−Mo) porphyry occurrences which are known to be present in the same area. This analysis of placer gold has indicated that the contribution of low sulfidation epithermal gold from Eureka Creek to the larger placers of the Indian River is minor. Consequently, the placer gold inventory of the Indian River is primarily orogenic in origin. Similarly, the characterization of placer gold in Blackhills Creek strongly suggests an orogenic source. This study has demonstrated for the first time that orogenic lode gold mineralization extends a considerable distance to the south of the southern Klondike goldfield. This information contributes to the regional models of gold mineralization in an area which is currently the focus of intensive exploration.  相似文献   

14.
莅香洼金矿发育有与金矿关系密切的地球化学异常,Au及相关元素的平均含量从安山岩→蚀变安山岩→蚀变岩→矿化蚀变岩呈几何级数递增。沿F985构造蚀变带走向,Pb、Ag与Au的组合异常通常与金的矿体晕分布一致,而As、Sb组合则更多反映了矿体前缘晕的组合特点,沿倾向,Au及相关元素自浅而深具有分段富集特征,并在1023m标高和976m标高构成二个浓集中心。其理想的元素轴向分带序列为:前缘晕As、Sb—Ba,矿体晕Au、Ag、Pb、Zn、Cu、Mo,矿尾晕(Cu、Mo)-(Co、Ni、Bi)。文章在前人研究的基础上,系统总结了莅香洼金矿床的地球化学特征,总结了构造蚀变岩型金矿床的地球化学找矿标志,建立了萑香洼金矿床的地球化学找矿模型。  相似文献   

15.
云南省墨江县金厂金矿床金银矿物成因矿物学研究   总被引:1,自引:0,他引:1       下载免费PDF全文
金、银系列矿物在云南墨江金厂金矿床中出现于蛇纹岩、含金石英脉.根据金银矿物的电子探针数据分析,确定了与成因产状对应的形态、赋存状态、矿物共(伴)生组合、化学成分等系列标型.从成矿早期到晚期,金矿物的结晶顺序为自然金→银金矿→自然银,金的成色有下降的趋势,银含量及矿物中微量元素总量却有明显增加的趋势.银金矿中微量元素总量...  相似文献   

16.
孙豪  宋扬  李发桥  李子琛  王旭  李阳  郑明  方颖 《矿床地质》2023,42(2):287-309
西藏具有形成巨型斑岩铜成矿系统的地质背景。浅成低温热液型金矿常发育于斑岩铜成矿系统上部,极具经济价值,但由于形成深度较浅,易于剥蚀,目前西藏地区尚未发现独立的浅成低温热液型金矿床。多龙超大型铜金矿集区位于西藏班公湖-怒江成矿带西段,产出有大型-超大型斑岩-浅成低温热液型铜金矿床,而是否存在独立的浅成低温热液型金矿,既是重大科学问题,也是勘查的重点方向。文章运用超景深高分辨数码显微镜、扫描电镜及电子探针等手段,系统研究了多龙矿集区尕尔勤矿区内的残坡积物和外围水系沉积物中746颗砂金的大小、形貌、核部元素及不透明矿物包体特征,发现尕尔勤矿区内广泛分布的砂金不是表生环境下生物化学或化学成因金,而是尕尔勤产出的金矿(化)体剥蚀的产物。砂金普遍含有较高的w(Bi)、极低的w(Cu),部分含有高的w(Hg)、w(Te);砂金w(Ag)变化较大(0.05%~40.21%);金成色变化范围较大(588~999);砂金富含Bi-Pb-Te-S系列矿物包体等,显示尕尔勤矿区可能存在一个遭受过剥蚀的浅成低温热液金矿床。  相似文献   

17.
A detailed chemical study has been carried out of 1794 gold grains from 55 sites within an area approximately 7 km by 18 km around Leadhills in the turbidite-facies, wacke-dominant Southern Uplands terrane of Scotland, formed as an accretionary thrust complex at the Laurentian continental margin during Ordovician and Silurian subduction of the Iapetus Ocean. The Leadhills area has had a long history of alluvial gold working, since at least 1510, and probably much earlier, but few bedrock sources of mineralisation have been located. Quantitative electron microprobe point analyses were obtained of sectioned and polished gold grains and of the associated microscopic inclusions, which in total comprised 35 types of opaque minerals. Microchemical X-ray maps were also obtained using a fully automated electron microprobe to show internal chemical compositional variation, to resolve the components of multiple and composite inclusions and to help in the identification of the smallest examples. Silver is present within most grains but Cu, Hg and Pd were only detected in about 3% of the grains. The shapes of cumulative frequency plots of the Ag contents of grains from different sites allow recognition of populations from different sources and enables comparison and differentiation between sites. In one of the main rivers, the Shortcleugh Water, the nature of the gold is generally similar, both in terms of Ag content and inclusion type, but a further type of gold, relatively rich in Ag and containing distinctive Ni and Sb-rich inclusions, is also present in 4 adjacent samples in one sector of the watercourse. This component of the samples reflects downstream dispersion, of up to 400 m, of gold grains from a mineralised structure cutting the river almost perpendicularly. Elsewhere abrupt changes in the nature of the alluvial gold within streams reflect a series of different sources and indicate limited glacial and alluvial dispersion. Four main types of gold which are considered to be derived from different varieties of source mineralisation can be recognised on the basis of composition and inclusion assemblage. The commonest type (ca. 70%) contains 8.4–13.1% Ag and inclusions, mostly of arsenopyrite, pyrrhotite, pyrite, chalcopyrite, galena, sphalerite and cobaltite, characteristics typical of mesothermal gold from shear-zones within a turbidite environment, suggesting sources within the local Lower Palaeozoic sedimentary rocks. The second type is richer in Ag (15.8–31.3%) with a basic igneous signature indicated from inclusions of Sb-rich gersdorffite, pyrite, Ni arsenide and other Ni-rich minerals, and shows some spatial association with discordant Tertiary basaltic dykes which cut the sedimentary rocks. The third type, mostly found in an area mantled by glacial drift, is poor in Ag (<1.2%) but frequently Cu-bearing and with inclusions of platinoids and Cu oxide. Associated with this type of gold are grains of the intermetallic compound Au3Cu and platinoids such as isoferroplatinum and a complex Ir-rich phase. Its source is problematical and could partly reflect detrital material associated with ophiolitic debris, which is common in the northernmost turbidites, and partly a local source of lode gold. The fourth gold type is also Ag-poor (<3.2%), but frequently contains Pd, up to 6.3%, while the inclusions comprise selenides of Pb, Hg and Cu. In nearby areas this type of gold is associated with Permian red beds and associated basaltic volcanics and also structures in the Lower Palaeozoic into which oxidising solutions derived from the red bed sequence have penetrated.  相似文献   

18.
板庙子金矿区主要矿石类型有含金黄铁矿型和含金多金属型,对两类矿石研究表明金赋存于黄铁矿和交代、穿切黄铁矿的黄铜矿中,主要与黄铁矿有关;对矿石中的A u、A g、Cu、Pb、Zn、Co、N i、B i、R b、S r、B a元素进行R型聚类分群,结果为A u B i、A g Zn Cu Co Pb N i、R b S r B a三群;对两类矿石与成矿关系密切的脉岩进行Q型聚类分群,结果表明金—黄铁矿型矿石与辉绿岩、煌斑岩、花岗斑岩有关,金—多金属型矿石主要与二长花岗斑岩、闪长玢岩有关,并与实际地质调查认识一致。由此明确了本矿区中金主要形成于金—黄铁矿阶段,少量形成于金—多金属阶段,随着岩浆由中性向酸性演化,成矿作用由贵金属向多金属矿化转变,并在空间上形成叠加。  相似文献   

19.
西岭金矿床是胶东金矿集区内近来新发现的超大型破碎蚀变岩型金矿床(475吨@4.56 g/t),位于著名的三山岛金矿床的东侧。本文在详实的野外地质观察的基础上,系统介绍了西岭金矿床的基础地质特征,并运用光学显微镜和扫描电镜观察,结合电子探针分析,系统研究了西岭金矿床金的赋存状态。西岭金矿床大量金矿物(银金矿和自然金)主要赋存在Ⅱ阶段石英-黄铁矿和Ⅲ阶段灰石英-多金属硫化物脉中。西岭金矿床金矿物主要有晶隙金、裂隙金和包体金三种赋存状态,以晶隙金为主。金的主要载体矿物为黄铁矿,次为石英、黄铜矿和方铅矿等。金矿物粒度大小包括粗粒金、中粒金、细粒金和微粒金,以细粒-微粒为主。金矿物形态有粒状、叶片状、线状、钩状、枝杈状和哑铃状等,以粒状为主。金矿物成分以Au和Ag为主,含微量的Cu、Cr、Fe、Ni、Te、S等元素。金成色为685~831,以银金矿为主,含少量自然金。综合地质和地球化学特征,西岭金矿床为蚀变岩型金矿床,是由早白垩世中温岩浆热液充填-交代形成。  相似文献   

20.
班公湖-怒江成矿带是西藏重要的铜多金属成矿带。嘎拉勒铜金矿床是该成矿带中发现较晚、研究程度较低且具代表性的矽卡岩型铜金矿床,矿石有用组分中金、银的赋存状态研究相对开展的较少,限制了矿床进一步的综合开发利用。作者通过野外地质调查与采样,采用光学显微镜鉴定、扫描电镜观察和X射线能谱仪测试分析等手段和方法,对矿石成分组分做了详细的研究,重点研究了矿床中金、银的赋存状态及主要载金矿物的特征。嘎拉勒铜金矿床金矿物以自然金、银金矿为主,其次为金银矿,可见粒间金、裂隙金及相对较少的包裹金形式,主要的载金矿物为石英、白云石、方解石、金属氧化物、硫化物及自然铋等。银矿物主要以金银系列矿物形式存在,少量自然银与放射性元素共生,此外,还有少量辉银矿。研究成果填补了该矿区金、银赋存状态研究的空白,对矿床的开发、利用有着重要的指示意义。  相似文献   

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