Mineral Geochemical Compositions of Tourmalines and Their Significance in the Gejiu Tin Polymetallic Deposits, Yunnan, China

The Gejiu tin polymetallic deposits are located in the southeastern part of Yunnan Province in China. A detailed electronic microprobe study has been carried out to document geochemical compositions of tourmalines from the deposits. The results indicate a systematic change of mineral geochemical compositions, which might be used as a mineral geochemical tracer for post-magmatic hydrothermal fluid, basin fluid and their mixture. The tourmalines from granite are schori with Fe/ （Fe＋Mg） ratios of 0.912-1.00 and Na/（Na＋Ca） ratios of 0.892-0.981. Tourmalines as an inclusion in quartz from the ore bodies are dravite with Fe/（Fe＋Mg） ratios of 0.212-0.519 and Na/（Na＋Ca） ratios of 0.786--0.997. Tourmalines from the country rocks are dravite with Fe/（Fe＋Mg） ratios of 0.313--0.337 and Na/（Na＋Ca） ratio of 0.599-0.723. Tourmalines from cassiterite-tourmaline veins that occur in crannies within the country rocks show distinct optical zoning with alternate occurrence of dravite and schorl, Fe/（Fe＋Mg）=0.374-0.843, Na/（Na＋Ca）=0.538-0.987. It suggests that schorl in granite and dravite in carbonatite are related to magmatic fluid and basin fluid respectively. When magmatic fluid rose up and entered into crannies of the country rocks, consisting mainly of carbonatite, basin fluid would be constantly added to the magmatic fluid. The two types of fluid were mixed in structural crannies of the sedimentary basin accompanied with periodic geochemical oscillations to form material records in chemical composition zonings of tourmalines.

Geochemical Characteristics of Rare Earth Elements in Gejiu Tin Polymetallic Deposits, Yunnan Province, China

In order to get a better understanding of metallogeny, the geochemical characteristics of REE and trace element for Gejiu tin polymetallic deposits were studied by comparing concentrations of REE and trace elements in different type ores and rocks, including skarn-type ore, bedded-type ore, vein-type ore, altered granite, country rocks. Results of this study indicated that the metallogenic matters for different type ores in the study area might be derived from the same origin source, which may be mainly related to granitic activities. Furthermore, there are some differences in concentrations of REE in different ores due to their different depositional mechanism during that time. LREE concentrations were enriched relatively in the vein-type ores and the bedded-type ores with relatively low total REE concentrations, whereas total REE concentrations were higher in the skarn-type ores with LREE and HREE concentrations in wide variation ranges.

Timing and structural controls on skarn-type and vein-type mineralization at the Xitian tin-polymetallic deposit, Hunan Province, SE China

Xitian tin-polymetallic deposit, located in the eastern Hunan Province, SE China, hosts quartz vein and skarn in the contact zone between carbonate and two stages granites. Critical geodynamic questions for South China are whether different types of mineralization form in the same time and how the magmatism–tectonic system controls the ore-forming process. Based on the distribution of the orebodies, six cassiterite samples from different types of mineralization are collected for dating. In-situ LA-MCICP-MS U–Pb isotopic data yielded concordia low intercept ages between 154 and 157 Ma, indicating that different types of mineralization belong to the same magmatism–mineralization system. Coupled with the study of the kinematic indicators, it suggests that the structural control of the wall rocks constrain the types of mineralization. These results provide further evidence of a close temporal link between the structure and the tin-polymetallic mineralization in Xitian deposit. Considering the structure in the district, granite dome plays an important role in the ore-forming process. The age and structural signatures in Xitian deposit are the response to the subduction of Pacific Plate.

Diversity of Mineralization and Spectrum of the Gejiu Superlarge Tin-Copper Polymetallic Deposit,Yunnan,China

The Gejiu （个旧） deposit is a superlarge tin-copper polymetallic ore-forming concentration area characterized by excellent metallogenic geological settings and advantageous ore-controlling factors. The deposit displays diverse mineralization properties due to different minerals and mineral deposit types. Based on the principal metallogenic factors, metallogenic mechanisms, mineralized components, and occurrence of mineral deposits or ore bodies, the Gejiu mineral district can be divided into 2 combinations of metallogenic series, 4 metallogenic series, 8 subseries, and 27 mineral deposit types. Spatial zonality is evident. The distribution regularity of the elements in both plane and section is Be-W, Sn （Cu, Mo, Bi, Be）-Sn, Pb, Ag-Pb, Zn around a granitic intrusion. The metallogenic epoch is mainly concentrated in the late Yanshanian. During this period, large-scale metallogenic processes related to movement caused by tectonics and magmatism occurred, and a series of magmatic hydrothermal deposits formed. The ore-forming processes can be divided into 4 stages： the silicate stage, the oxide stage, the sulphide stage, and the carbonate stage. Based on the orderliness and diversity （in terms of time, space, and genesis） of the mineralization, the authors have developed a comprehensive spectrum of ore deposits in the Gejiu area. This newly proposed diversity of mineralization and the spectrum developed in this work are useful not only for interpreting the genesis of the Gejiu deposit but also for improving mineral exploration in the area, and in particular, for finding large deposits.

Geology and sulfur isotope geochemistry of Dafulou tin-polymetallic deposit in Dachang orefield, Guangxi, China

No. 22 ore of Dafulou deposit was systematically analyzed for sulfur isotopes. The results show that the δ34S values of sulfide minerals, ranging from 0.154 to +0.218% and with an average value of +0.114 1%, are mostly positive and characterized by rich sulfur(S) content. This suggests that the sulfur of the Dafulou ore deposit is derived from magma and relates to the Longxianggai concealed granite, which points to the important role of magma during mineralization and implyies the product of the active continental margin. By comparison between the Dafulou and the Kengma tin deposit, significant differences exist in the sulfur isotope composition. In the Kengma deposit, the sulfur isotope composition is characterized by the high negative value, which is different from the Dafulou tin-polymetallic deposit. The difference of the enrichment and fractionation of the sulfur isotope is the synthesized result of the metallogenic conditions. It also has the difference in the metallogenic environment and metallogenic characteristics of the deposit in the same ore belt.

Bainiuchang super-large silver-polymetallic ore deposit related to granitic magmatism in Mengzi, Yunnan

Bainiuchang silver-polymetallic ore deposit is located in the southeast Yunnan tin-polymetallic metallogenic belt.The probable reserves and inferred resources of the deposit are of 6 470 t Ag and 1.10 Mt Pb and 1.72 Mt Zn and 86 kt Sn.Orebodies of the deposit occur in clastic-carbonate rocks of Tianpeng Formation and Longha Formation of the middle Cambrian System above the Bainiuchang concealed granite of the late Yanshan period.The concealed granite has the characteristics of tin-bearing granites.Abundance of the mineralization elements Sn,Cu,Zn,Pb,Ag and Sb is high in the granitic rocks.Sulphur isotope data of the metal sulphides indicate that most sulphur is derived from the magmas.The ores are similar in rare earth element(REE)patterns to the granitic rocks.The granitic magma activity results in ore-bearing structures.Rocks of the Middle Cambrian System above the concealed intrusion suffer from skarnization,hornfelsing,marbleization,siliconizing and carbonatization.The mineralization elements Sn,Cu,Zn,Pb,Ag and Sb successively appear from the top of the granite to surrounding rocks.These evidences indicate that the granitic magmatism is the principal mineralization factor.The opinion that the south Bainiuchang ore field and the north Awei ore block are tin and copper potential exploration areas was put forward and was verified by drilling tests.

粤东金坑锡铜多金属矿燕山期岩浆热液叠加成矿

金坑锡铜多金属矿位于广东莲花山断裂带北东段,是近些年来在粤东地区新发现的典型锡铜多金属矿,关于该矿床的成因类型和成矿机制一直存在较大争议。矿区勘查工作在马山矿段首次发现伴有明显铜矿化的热液隐爆角砾岩,对于揭示矿床成因具有重要意义。LA-ICP-MS锆石U-Pb年代分析结果显示,花岗质角砾成岩年龄约为150 Ma,ε_(Hf)(t)值为-8.20~-4.55,二阶段Hf模式年龄值为1.73~1.49 Ga,指示岩浆主要来自于中元古代地壳物质,并有地幔物质加入。硫化物原位硫同位素分析结果显示,不同阶段硫化物硫同位素组成具有明显差别。第一阶段(Py-Ⅰ)和第二阶段(Py-Ⅱ)黄铁矿存在显著的硫同位素变化,前者为-0.65‰~1.11‰(n=5),后者为1.30‰~1.93‰(n=5),与Py-Ⅱ共生黄铜矿同位素值为1.42‰~1.87‰(n=16)。第三阶段硫化物中黄铜矿δ^(34)S值为3.69‰~4.32‰(n=4),其中隐爆角砾岩胶结物中黄铜矿(Ccp-Ⅲa)δ^(34)S为3.69‰~3.74‰,略低于第三阶段石英-绿泥石脉中黄铜矿(Ccp-Ⅲb)δ^(34)S值(4.29‰~4.32‰)。第四阶段黄铁矿(Py-Ⅳ)δ^(34)S值为-4.87‰(n=1),黄铜矿(Ccp-Ⅳ)δ^(34)S值为-3.07‰(n=1)。基于成岩成矿年代及硫化物原位硫同位素分析,文章认为金坑锡铜多金属矿床可能存在两期岩浆热液活动的叠加,其中~150 Ma壳幔混合来源花岗质岩浆活动可能是触发矿区铜矿化的重要岩浆事件,早于后期锡矿的形成(~144 Ma),这一发现有望为莲花山断裂带锡铜多金属矿指引新的方向。

大兴安岭南段北大山岩体的年代学和地球化学:对岩石成因及成矿潜力的指示

大兴安岭南段发育包括维拉斯托、黄岗、安乐、大井、毛登和边家大院等锡多金属矿床,是我国北方最重要的锡多金属成矿带。北大山岩体是该锡多金属成矿带规模最大,出露最完全的花岗质侵入体,其北部主要为石英二长斑岩,南部为黑云母花岗岩,且南部岩相中常见电气石和绿柱石,被认为是区内锡多金属矿床的成矿母岩。然而,目前对该岩体岩石成因及其稀有金属成矿潜力的认识却存在较大争议。本文在对北大山岩体开展岩相学观察和锆石U-Pb定年的基础上,通过全岩地球化学和锆石Hf同位素分析,结合MELTS热力学模拟计算,试图阐明该岩体的成因类型、源区特征和演化过程,并讨论其成矿潜力。锆石U-Pb定年结果显示,北大山岩体北部的石英二长斑岩形成于143.4±1.3Ma,南部黑云母花岗岩形成于142.6±1.3Ma,与大兴安岭南段早白垩世锡多金属成矿年龄峰值相一致。北大山岩体中含自形富水矿物角闪石及黑云母、富碱(K_(2)O+Na_(2)O=8.58%~9.34%)、ACNK/CNK值介于0.97~1.02,P_(2)O_(5)含量低(<0.14%)且与SiO_(2)含量呈负相关,指示该岩体为高钾钙碱性I型花岗岩。岩体的锆石Hf同位素组成较为亏损(ε_(Hf)(t)值平均6.81,n=20),且全岩锆饱和温度较高(平均值为813℃),指示其为新生地壳物质高温熔融的产物。主量元素变化关系和MELTS模拟结果表明,北大山岩体为高钾钙碱性岩浆体系不同程度分离结晶的产物,其中北部石英二长斑岩样品之间结晶分异程度较低,而南部黑云母花岗岩的结晶分异程度较高。北大山岩体的形成时代、源区特征和氧化还原条件(△FMQ-2.5)与大兴安岭南段稀有金属花岗岩类似,具有一定的锡多金属成矿潜力,但其初融温度、挥发分组成(相对富B贫F)、分异演化程度(结晶分异和熔体-流体相互作用程度相对较低)明显不同于维拉斯托矿床成矿碱长花岗斑岩,不会是该矿床的成矿母岩。

云南个旧锡多金属矿集区电气石地球化学组成和硼同位素特征——对成矿流体性质和演化的约束

个旧锡矿集区发育与晚白垩世高分异花岗岩有关的世界级Sn-Cu多金属矿床,其成矿物质的来源及流体演化过程一直是研究的热点和难点。个旧地区电气石广泛发育于碳酸盐岩、花岗岩及矽卡岩中,但对电气石尚未进行系统研究,电气石与成矿之间的关系尚未明确。本文对不同类型电气石开展了系统的岩相学观察和电子探针(EPMA)、LA-ICP-MS微量元素和硼同位素分析。结果表明,所有电气石都属于碱性电气石,TurⅠ、TurⅡ、TurⅣ为热液成因,TurⅢ为岩浆成因。岩浆电气石相比于热液电气石具有更低的Mg、Ca等元素,TurⅠ电气石高含量的Sr表明受到了围岩的混染。电气石的微量元素变化表明,从似斑状花岗岩到等粒花岗岩,随着岩浆分异程度逐渐增加,Sn在岩浆中逐渐富集,在似斑状花岗岩和接触带矽卡岩中沉淀卸载。个旧不同类型电气石具有均一的δ11B值(−15.2‰~−12.8‰),与花岗岩的组成范围一致,表明成矿物质来源均来源于花岗质岩浆。

湖南界牌岭大型锡-萤石矿床勘查模型与深部找矿预测

湖南界牌岭锡多金属矿床位于南岭成矿带中段,是近年来新发现的以锡和萤石为主,伴生锂、铍、铌、钽、锌等重要资源的大型矿床。该矿床矿化元素多且规模大、矿化分带性强、成矿时代也较新(~90 Ma),使其在湘南钨多金属矿集区内独具特色。文章在详细的矿床地质工作基础上,对界牌岭不同矿化段的萤石和锡石进行了矿物学研究和微区原位微量元素对比分析。研究结果显示,萤石由深到浅表现为明显的正Ce异常向负Ce异常、负Eu异常向正Eu异常转变,指示成矿流体向上运移过程中氧逸度逐渐升高。浅部矿体与深部花岗斑岩中萤石的稀土元素配分特征一致,指示两者均为深部富F花岗质岩浆的产物。相较于南岭地区云英岩型和石英脉型锡矿,界牌岭锡石中Nb-Ta含量偏低,但高于矽卡岩型锡矿,具有富Fe、贫W的特征,较低的Zr/Hf值(平均为2.76)。对比研究认为,界牌岭锡矿体仍处于该岩浆热液系统中-远端,推测其深部至隐伏岩体仍具较大找矿空间。结合前人研究,文章综合构建了界牌岭锡萤石矿床成矿模式,并提出了相应的勘查标识,圈定了界牌岭深部近花岗岩体矽卡岩型-云英岩型-石英细脉型锡(钨)铌钽矿、北北东向主断裂北段深部锡多金属矿、斑岩体内及深部接触带锡锂铌钽矿3个方向的找矿预测靶区。

江西云山矿田锡多金属矿床特征及找矿前景分析

近年来,对云山矿田内云山复式岩体与锡矿化的相关研究取得了较为突出的成果,但寻找大型锡多金属矿床一直未取得重大突破。该矿田内锡矿化主要产于云山复式岩体接触带的岩突、岩舌、岩体凹谷及北北东向断裂等部位,形成的矿床类型主要有接触交代型、岩浆热液型和变质热液型。其中,接触交代型与岩浆热液型具有矿体厚度较大、蚀变强、品位较高等特点。目前,云山矿田已发现多处小型锡矿床,其矿体均赋存在岩体接触带和北北东向断裂。该矿田内许多区域具有相似的成矿条件,如果加大地质勘查力度,有望实现找矿突破。

Identification of the anomaly component using BEMD combined with PCA from element concentrations in the Tengchong tin belt, SW China

Concentration of elements or element groups in a geological body is the result of multiple stages of rockforming and ore-forming geological processes.An ore-forming element group can be identified by PCA(principal component analysis)and be separated into two components using BEMD(bi-dimensional empirical mode decomposition):(1)a high background component which represents the ore-forming background developed in rocks through various geological processes favorable for mineralization(i.e.magmatism,sedimentation and/or metamorphism);(2)the anomaly component which reflects the oreforming anomaly that is overprinted on the high background component developed during mineralization.Anomaly components are used to identify ore-finding targets more effectively than ore-forming element groups.Three steps of data analytical procedures are described in this paper;firstly,the application of PCA to establish the ore-forming element group;secondly,using BEMD on the o re-forming element group to identify the anomaly components created by different types of mineralization processes;and finally,identifying ore-finding targets based on the anomaly components.This method is applied to the Tengchong tin-polymetallic belt to delineate ore-finding targets,where four targets for Sn(W)and three targets for Pb-Zn-Ag-Fe polymetallic mineralization are identified and defined as new areas for further prospecting.It is shown that BEMD combined with PCA can be applied not only in extracting the anomaly component for delineating the ore-finding target,but also in extracting the residual component for identifying its high background zone favorable for mineralization from its oreforming element group.

维拉斯托稀有金属-锡多金属矿床铌铁矿族矿物特征及其对岩浆-热液演化的指示

大兴安岭南段维拉斯托大型稀有金属-锡多金属矿床的成矿岩体从深部的中粒花岗岩向上逐渐过渡为斑状细粒碱长花岗岩,记录了岩浆演化的不同阶段。为查明铌铁矿族矿物成分、结构变化及其与岩浆演化过程的耦合关系,文章对采自不同深度的3种类型花岗岩(中粒花岗岩、石英斑晶不具雪球结构的斑状细粒富云母碱长花岗岩和具雪球结构的斑状细粒碱长花岗岩)中的铌铁矿族矿物进行了详细的电子探针成分分析和元素面扫工作。维拉斯托矿床铌铁矿族矿物主要为铌铁矿,发育渐变环带结构,从核部到边部Ta含量增加,且斑状细粒富云母碱长花岗岩和斑状细粒碱长花岗岩铌铁矿族矿物边部的铌铁矿、铌锰矿相较于幔部和核部的铌铁矿,其Ta含量具有明显的组分间隔;铌铁矿族矿物Mn/(Fe+Mn)原子比具有多种演化趋势,与分离结晶的矿物相和流体交代作用有关。中粒花岗岩和斑状细粒富云母碱长花岗岩中的铌铁矿结晶于岩浆阶段,斑状细粒碱长花岗岩中的铌铁矿族矿物结晶于岩浆-热液过渡阶段。其中,斑状细粒富云母碱长花岗岩铌铁矿边部Ta含量增加与铁锂云母的分离结晶作用有关,斑状细粒碱长花岗斑岩铌铁矿族矿物边部Ta含量的突变与岩浆-热液过渡阶段的水硅酸盐液体中Ta溶解度的增加有关。斑状细粒碱长花岗岩石英斑晶中共生的熔体包裹体和流体包裹体表明,石英斑晶的雪球结构形成于熔-流体共存的岩浆-热液过渡阶段,出溶的富钨流体交代铌铁矿族矿物在其边部形成富铌钽的黑钨矿,并导致边部铌铁矿族矿物中的Mn含量增加。铌铁矿族矿物结构和成分的连续变化可以用来示踪岩浆-热液演化过程。

综合土壤和重砂测量在内蒙古扎鲁特旗坤得来扎拉格地区锡多金属找矿中的应用

为明确找矿方向,实现找矿突破,在坤得来扎拉格地区开展了1∶10000土壤地球化学测量和自然重砂测量,对土壤中W、Sn、Pb、Zn等10种元素的地球化学特征和自然重砂的重矿物特征进行了初步总结。利用相关分析对元素的共生组合关系进行了研究,显示区内地球化学元素组合为Pb-Zn-Ag-Cu和Sn-W-Mo-Bi,其中Sn富集分异最为强烈,Sn含量峰值大于300×10^(-6)。通过自然重砂测量查明了矿区内有锡石、石榴子石、钛铁矿、锆石等23种重矿物,并通过重矿物组合特征、锡石延伸系数和地质特征初步查明了矿区锡多金属矿的成因为热液脉型。最终结合元素地球化学特征、锡石分布组合特征和异常区内已发现的矿化线索,优选出了坤得来扎拉格Sn-W多金属找矿预测区和坤得来扎拉格南Pb-Zn-Ag-Cu-Sn多金属找矿预测区。

尼日利亚中生代碱性花岗岩和黑云母花岗岩成因及其对锡多金属找矿的指示

尼日利亚中生代环状杂岩中产出丰富的含锡(铌钽)等多金属的花岗岩,其中与成矿相关且占主体的2种岩石类型是碱性花岗岩和黑云母花岗岩,前者具有含碱性暗色矿物过碱质特征,后者具有含黑云母过铝质特征。前人对2种共生的岩石对锡(铌钽)成矿作用可能的制约机制还未深入探讨,综合分析前人研究资料,为理解非造山A型花岗岩锡(铌钽)成矿作用提供新视角,进一步明确找矿方向。2种岩石绝大多数在侏罗纪侵位,但在同一杂岩体中,碱性花岗岩锆石结晶普遍稍早于黑云母花岗岩,且前者分异程度稍弱于后者。碱性花岗岩是起源于富集地幔岩浆在极端分离结晶作用下的产物,但此过程中有部分地壳物质的混染。过铝质黑云母花岗岩并非与造山型过铝质花岗岩一样来自地壳物质的熔融,它更可能是来自于碱性花岗岩同一母岩浆演化的另一个混染了更多地壳物质的晚期分支。与俯冲背景的成锡花岗岩一样,尼日利亚锡多金属富集主要与弱过铝质黑云母花岗岩有关,受岩浆后期出溶流体的显著影响。碱性花岗岩对锡(铌钽)元素的富集程度,大致代表了未受出溶流体影响时共生黑云母花岗岩的锡(铌钽)含量。成矿物质来源为泛非基底围岩,元素的富集成矿主要被分离结晶和流体出溶行为控制。尼日利亚不成矿环状杂岩体中,黑云母花岗岩和碱性花岗岩的锡(铌钽)含量都偏低,两者的Sn含量范围为4×10^(-6)~13×10^(-6);而对于成矿杂岩体,两者锡(铌钽)含量基本高于不成矿杂岩体,但其中与成矿密切相关的黑云母花岗岩锡(铌钽)含量反而较碱性花岗岩偏低,其中碱性花岗岩Sn含量范围为21×10^(-6)~205×10^(-6),黑云母花岗岩Sn含量范围为10×10^(-6)~62×10^(-6),表明熔体中成矿元素含量高低及后期流体出溶是决定能否成矿的关键。因此,高锡(铌钽)含量杂岩体中具有较低Sn含量的黑云母花岗岩是寻找锡多金属矿的第一选择。

湘南绿紫坳锡多金属矿床硅钙面控矿作用及其找矿意义

湘南地区是南岭地区重要的锡多金属矿勘查区,勘查区的控矿规律研究是实现找矿突破的关键环节。以大义山矿田绿紫坳锡多金属矿床为例,通过野外地质调查和室内综合研究,总结了锡多金属成矿规律,认为锡多金属矿体主要受3类硅钙面控制:Ⅰ类为花岗岩体与碳酸盐岩的“硅钙面”接触界面,形成了Ⅰ号矿带的矽卡岩型铜锡矿体;Ⅱ类为泥盆系上统锡矿山组下段灰岩与上段碎屑岩界面,形成了Ⅱ~Ⅴ号矿带的锡铅锌矿体;Ⅲ类为泥盆系中统跳马涧组砂岩与棋梓桥组灰岩的硅钙界面,形成了Ⅵ和Ⅶ号矿带的锡铅锌多金属矿体。结合成矿地质条件和控矿规律,构建了锡多金属构造控矿模式。综合分析了区内控矿要素特征,认为白水源地段为有利找矿靶区。通过勘查发现了7条锡铅锌多金属矿体,产于第Ⅰ类硅钙面中铜锡矿体1条、第Ⅱ类硅钙面中锡铅锌矿体1条、第Ⅲ类硅钙面中锡铅锌矿体1条,断裂带中矿体4条,获得锡铅锌资源量约1.5万t,取得了矿床南部锡多金属矿的找矿进展。通过对比分析湘南地区香花岭矿田和荷花坪矿田等重要锡多金属矿床,认为硅钙面控矿对湘南地区锡多金属矿具有普遍意义,加强硅钙面的控矿规律研究对于指导湘南地区锡多金属找矿突破具有重要意义。

内蒙古维拉斯托锡多金属矿床流体包裹体及其对成矿的指示

维拉斯托位于中亚造山带东部的大兴安岭以南,成型的锡成矿带主要在我国南岭,大兴安岭是我国北方的锡成矿地区。矿床成矿阶段包括斑岩体内的Ⅰ天河石化-钠长石化阶段、Ⅱ云英岩阶段、Ⅲ隐爆角砾岩阶段和Ⅳ晚期硫化物阶段。流体包裹体研究显示,流体包裹体的类型以液相为主的两相包裹体较多,而还存在以气相为主的两相包裹体,含子晶的三相包裹体和H_(2)O-CO_(2)包裹体,此三类数目较少。Ⅰ天河石化-钠长石化阶段均一温度为358~463℃,盐度为4.7%~8.6%NaCleqv,密度为0.46~0.71 g/cm^(3);Ⅲ隐爆角砾岩阶段均一温度为233~318℃,盐度为3.55%~10.61%NaCleqv,密度为0.77~0.87 g/cm^(3);Ⅳ晚期硫化物阶段均一温度为247~300℃,盐度为6.88%~7.93%NaCleqv,密度为0.85~0.86 g/cm^(3)。对矿物所含包裹体显微测温分析结果成矿流体具中高温、低盐度、中密度的性质,推测为同源流体来源及其演化。早期的基性-超基性岩浆演化携带成矿元素之后与深源岩浆混合一起形成成矿流体,成矿流体冷却是锡矿成矿的原因。

湖南锡田—邓阜仙矿集区钨锡多金属矿勘查工作进展及主要成果

湖南锡田—邓阜仙矿集区位于南岭成矿带,成矿条件优越,通过对矿集区复式岩体及其相关的钨锡多金属矿产进行调查评价和研究,至今已提交或估算钨锡矿产资源约43×10^(4) t。本文系统梳理和总结了矿集区近20年来钨锡多金属矿床丰硕的找矿和科研工作成果,在简要阐述矿集区成矿地质特征的基础上,从成岩成矿作用、控矿构造、成矿空间和矿化类型、找矿标志等多方面分析了复式岩体多期次成矿作用,总结了不同的物探方法组合应用及其有效性,并对上述成矿预测理论进行了工程验证,成果推广及应用效果显著。

广东陆河县仙水沥锡多金属矿地质特征及找矿方向

仙水沥锡多金属矿体主要赋存于早白垩世粗粒斑状黑云母二长花岗岩与下侏罗统吉水门组片岩内外接触带,成矿构造主要为莲花山断裂形成的北东向裂隙,蚀变主要有绿泥石化、石榴子石化、绢云母化及硅化等,根据矿体产出特征及主要控矿因素推断,初步认为矿床为中高温岩浆热液充填交代型矿床。在其外围及深部仍有找矿空间。

广东普宁锡岭岗锡多金属矿地质特征及找矿方向

锡岭岗锡多金属矿锡矿体位于晚侏罗世黑云母二长花岗岩与下侏罗统上龙水组接触带,云英岩化、褐铁矿化强。矿床成因类型为热液裂隙充填矿床、工业类型为云英岩型矿床,岩体内外接触带、南北向次级断裂、云英岩化、硅化、化探元素组合异常和前人遗留老硐、旧坑等为重要的找矿方向。