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1.
西秦岭造山带是我国最重要的金成矿带之一。以往研究大多认为造山型金矿床和(类)卡林型金矿床是西秦岭主要的金矿床类型,并且两类金矿床的金成矿作用主要与造山过程中的区域变质作用有关,而与岩浆活动不存在直接的成因联系。位于西秦岭造山带西段的夏河—合作地区大面积出露花岗岩类侵入体,其周缘发育有富金的夕卡岩型铜(钨)矿床。近年来该地区新发现的多个大型—超大型石英脉型金矿床和微细粒浸染型金矿床都与中酸性侵入岩的空间关系紧密,暗示这些金矿床可能和岩浆活动有成因联系。论文在作者研究结果以及总结前人成果基础上,综述了夏河—合作地区典型金(铜)矿床的地质矿化特征、地球化学特征、时空分布特征,以及中酸性侵入岩的岩性特征、形成时代和演化过程。年代学研究结果显示,夏河—合作地区的早子沟微细粒浸染型金矿床、德乌鲁夕卡岩型金(铜)矿床和老豆石英脉型金矿床均形成于250~240 Ma,与邻近的早中三叠世花岗闪长质石英闪长质侵入岩近于同时形成。拉布在卡等石英脉型金矿床略晚于区内中三叠世末期侵位的闪长玢岩脉(约230~225 Ma)形成。H、O、S、C、B、Pb等多种同位素地球化学特征指示该地区早中三叠世金矿床的成矿热液均为岩浆来源,并且显示低氧逸度的特征。早中三叠世中酸性侵入岩的还原性钛铁矿系列花岗岩类特征,以及同时代的多种金矿化类型和成矿分带性,表明夏河—合作地区在早中三叠世(约250~230 Ma)多期次侵位的钛铁矿系列I型中酸性岩浆是金成矿作用的成矿流体和成矿物质的主要来源,其中与250~240 Ma多期金成矿事件有关的准铝质弱过铝质、高钾钙碱性系列花岗岩类侵入岩均经历了幔源基性熔体和壳源酸性熔体的岩浆混合作用,而与约230 Ma的金成矿作用有关的闪长质岩浆岩则可能指示了更多幔源基性熔体的加入。与金(铜)成矿有关的早中三叠世还原性中酸性岩是在古特提斯洋俯冲过程中局部弧后伸展条件下交代富集地幔楔部分熔融形成的基性岩浆与壳源酸性岩浆混合作用的产物。夏河—合作地区形成于早中三叠世的夕卡岩型、电气石石英脉型、石英方解石脉型和微细粒浸染型金矿床共同构成了一个与还原性侵入岩有关的金成矿系统。夏河—合作地区与还原性侵入岩有关的金成矿系统的发现,丰富了西秦岭造山带区域成矿作用的类型,并为西秦岭西段其他早中三叠世岩浆岩分布区(如青海同仁地区)的金矿勘查工作提供了新的思想和方向。  相似文献   

2.
The Liziyuan gold deposit, situated on the south side of the Shangdan suture zone, West Qinling Orogen, occurs in metamorphic volcanic rocks(greenschist facies) of the early Paleozoic Liziyuan Group and in Indosinian Tianzishan monzogranite. Orebodies in the Liziyuan gold field are controlled by the ductile-brittle shear zone, and by thrusting nappe faults related to the Indosinian orogeny. In detail, this paper analyzed the geological characteristics of the Liziyuan gold field, and the Pb isotopes of the Lziyuan host rocks, granitoids(Tianzishan monzogranite and Jiancaowan syenite porphyry), sulfides, and auriferous quartz veins by multiple-collector inductively coupled plasma mass spectrometry(MC-ICPMS). In addition, previous data on the sulfur, hydrogen, and oxygen isotopes were employed to discuss the possible sources of the ore-forming fluids and materials, and to further understand the tectonic setting of the Liziyuan gold deposit. The sulfides and their host rocks(Lziyuan Group), Tianzishan monzogranite and Jiancaowan syenite porphyry, and auriferous quartz veins have similar Pb isotopic compositions.Zartman's plumbotectonic model diagram shows that most of the data for the deposit fall near the orogenic Pb evolutionary curve or within the area between the orogenic and mantle Pb evolutionary curves. In the△β-△γ diagram, which genetically classifies the lead isotopes, most of the data fall within the range of the subduction-zone lead mixed with upper crust and mantle. This indicates that a complex source of the ore lead formed in the orogenic environment. The δ~(34)S values of the sulfides range from 3.90 to 8.50‰(average6.80‰), with a pronounced mode at 5.00‰-8.00‰. These values are consistent with that of orogenic gold deposits worldwide, indicating that the sulfur sourced mainly from reduced metamorphic fluids. The isotopic hydrogen and oxygen compositions support a predominantly metamorphic origin of the oreforming fluids, with possible mixing of minor magmatic fluids, but the late stage was dominated by meteoric water. The characteristics of the Liziyuan gold deposit formed in the Indosinian orogenic environment of the Qinling Orogen are consistent with those of orogenic gold deposits found worldwide.  相似文献   

3.
Predicting realistic targets in underexplored regions proves a challenge for mineral explorers. Knowledge-driven prospectivity techniques assist in target prediction, and can significantly reduce the geographic search space to a few locations. The mineral prospectivity of the underexplored west Kimberley region was investigated following interpretation of regional gravity and magnetic data. Emphasis was placed on identifying geological structures that may have importance for the mineral prospectivity of the region. Subsurface structure was constrained through combined gravity and magnetic modelling along three transects. Crustal-scale structures were interpreted and investigated to determine their depth extent. These interpretations and models were linked to tectonic events and mineralization episodes in order to map the distribution of minerally prospective regions using a knowledge-driven mineral systems approach. A suite of evidence layers was created to represent geological components that led to mineralization, and then applied to each mineral system where appropriate. This approach was taken to provide a more objective basis for prospectivity modelling. The mineral systems considered were 1) magmatic Ni-sulphide, 2) carbonate-hosted base metals, 3) orogenic Au, 4) stratiform-hosted base metals and 5) intrusion-related base metals (including Sn–W, Fe-oxide–Cu–Au and Cu–Au porphyry deposits). These analyses suggest that a geologically complex belt in the Kimberley Basin at the boundary to the King Leopold Orogen is prospective for magmatic-related hydrothermal mineral systems (including Ni, Au and Cu). The Lennard Shelf is prospective for carbonate-hosted base metals around a feature known as the 67-mile high, and parts of the King Leopold Orogen are prospective for stratiform-hosted base metals. These results show that knowledge-driven mineral system modelling is effective in identifying prospectivity in regional-scale studies of underexplored areas, as well as drastically reducing the search space for explorers working in the west Kimberley.  相似文献   

4.
Systematic spatial analysis of mineral deposit point patterns can reveal significant spatial properties of mineral systems, with major implications for regional mineral prospectivity modelling. For valid results, a study area needs to be clearly defined, taking into account permissiveness of the geological units for a particular mineral system and effects of cover. Standard statistical tests assuming an isometric contiguous study area with regionally homogeneous distribution of deposits are likely to produce invalid results. Analysis of regional uniformity of spatial deposit density is required for adequate design and interpretation of tests for clustering. Spatial distribution of orogenic gold deposits in the Hodgkinson Province in Queensland and the Western Lachlan Orogen in Victoria (Australia) indicates the presence of significant regional linear metallogenic zones, probably controlled by deep crustal domain boundaries oblique and not related to any recognised major faults. Within the metallogenic zones in both regions, individual gold occurrences are strongly clustered into ore fields, but the distribution of ore fields is random.  相似文献   

5.
Regional Exploration Targeting Model for Gangdese Porphyry Copper Deposits   总被引:1,自引:0,他引:1  
An exploration targeting model for Gangdese porphyry copper deposit in Tibet, China, is constructed based on (i) the age of porphyry intrusions within Gangdese magmatic arc; (ii) the regional‐scale normal E–W, N–S and N–E striking faults; and (iii) comprehensive anomalously high concentrations of Cu‐Mo‐Au‐Ag‐Pb‐Zn. These targeting elements are derived from geological map and geochemical dataset, and are integrated by weights of evidence with the aid of geographic information system (GIS). The resulting prospectivity for porphyry copper deposits delineated by posterior probability demonstrates that the target areas extend along the Yaluzangbujiang River and contain the two large deposits, Qulong and Chongjiang, located in the eastern and central part of the Gangdese belt, respectively. These results indicate that the proposed exploration targeting model is a potential tool to map regional‐scale mineral prospectivity. The target areas with high values of favorability, especially where high concentrations of Cu‐Mo‐Au‐Ag‐Pb‐Zn are present, are the potential areas for finding undiscovered porphyry copper deposits.  相似文献   

6.
This paper presents a review of the available information on the significant porphyry, epithermal, and orogenic gold districts in Argentina, including the tectonic, geological, and structural settings of large deposits or deposits that have been exploited in the past. Based on this review of the geology and mineralization, targeting models are developed for epithermal and orogenic gold systems, in order to produce GIS-based prospectivity models. Using publically available digital geoscience data, weights of evidence and fuzzy logic prospectivity maps were generated for epithermal and orogenic gold mineralization in Argentina. The results of the prospectivity mapping highlight existing gold deposits within known mineralized districts throughout Argentina, as well as other highly prospective areas with no known deposits within these districts. Additionally, areas within Argentina that have no known gold mineralization (based on publically available information) were highlighted as being highly prospective based on the models used.  相似文献   

7.
This paper reports a deposit-scale GIS-based 3D mineral potential assessment of the Jiama copper-polymetallic deposit in Tibet, China. The assessment was achieved through a sequential implementation of metallogenic modelling and 3D modelling of geology, geochemistry and prospectivity. A metallogenic model for the Jiama deposit and 3D modelling workflow were used to construct multiple 3D layers of volumetric and triangular mesh models to represent geology, geochemistry and ore-controlling features in the study area. A GIS-based 3D weights-of-evidence analysis was then used to estimate the subsurface prospectivity for Cu (Mo) orebodies in the area, which led to the identification of three prospective deep-seated exploration targets. Additionally, the geochemical modelling indicates three potential fluid flow pathways based on the 3D zonation of major geochemical elements and their ratios, particularly the Zn/Pb ratios, which support the results of the weights of evidence model.  相似文献   

8.
Buffer zones in bo\th two-dimensional (2D) and three-dimensional (3D) spaces are commonly used in prospectivity mapping. The method completes a modelling that starts with a real example and progresses to the development of a virtual model. This includes the consideration of lithological or structural contacts at depth, which is a theoretical concept based on extrapolation of data collected in the field, rather than an empirical observation of the feature based on physical samples. This contribution documents an improved buffer analysis method for the study of 3D-space that is implicit (rapid), precise (smooth) and based on triangulated characteristics, which can be used to construct influence domains of geological models. As traditional 2D GIS-based mineral potential mapping is gradually becoming limited with time, mineral potential mapping in three dimensions (3D) is increasingly becoming an important tool in finding concealed economic mineralization. This contribution documents an improved methodology of buffer analysis for prospectivity mapping processing mineralized favourable models rather than describing an advance in the geometry of surface rendering of “geological complexity”. Measures used in this buffer analysis include the: (1) voxelization of geological objects (i.e. assigning numerical values of features on a regular cube in 3D-space); (2) revision of the 3D Euclidean distance transform and the calculation of signed distance field; (3) extracting surfaces from the field; and (4) construction of a buffer-surface based on a “discrete smooth interpolation” (DSI) algorithm. Furthermore, this contribution constructs 3D models using a buffer analysis algorithm and prospectivity mapping introduced here, which is based on real data from the Jiama Cu-polymetallic deposit in Tibet and Daye Fe deposit in the Hubei Province, China. This contribution also presents a comparison between voxel and irregular triangle models, which illustrate that irregular triangle mesh buffer analysis (ITB) can improve modelling techniques for GIS-based 3D mineral potential mapping. The outcome is an increase in the accuracy of prospectivity mapping.  相似文献   

9.
A major challenge for mineral exploration geologists is the development of a transparent and reproducible approach to targeting exploration efforts, particularly at the regional to camp scales, in terranes under difficult cover where exploration and opportunity costs are high. In this study, a three-pronged approach is used for identifying the most prospective ground for orogenic gold deposits in the Paleoproterozoic Granite-Tanami Orogen (GTO) in Western Australia.A key input to the analyses is the recent development of a 4D model of the GTO architectural evolution that provides new insights on the spatio-temporal controls over orogenic gold occurrences in the area; in particular, on the role of pre-mineralization (pre-1795 Ma) DGTOE–DGTO1–DGTO2 architecture in localization of gold deposits and the spatial distribution of rock types in 3D. This information is used to build up a model of orogenic gold minerals system in the area, which is then integrated into the three mutually independent but complementary mineral prospectivity maps namely, a concept-driven “manual” and “fuzzy” analysis; and a data-driven “automated” analysis.The manual analysis involved: (1) generation of a process-based gold mineral systems template to aid target selection; (2) manual delineation of targets; (3) manual estimation of the probability of occurrence of each critical mineralization process based on the available information; and (4) combining the above probabilities to derive the relative probability of occurrence of orogenic gold deposits in each of the targets. The knowledge-based Geological Information System (GIS) analysis attempts to replicate the expert knowledge used in the manual approach, but queried in a more systematic format to eliminate human heuristic bias. This involves representing the critical mineralization processes in the form of spatial predictor maps and systematically querying them through the use of a fuzzy logic model to integrate the predictor maps and to derive the western GTO orogenic gold prospectivity map. The data-driven ‘empirical’ GIS analysis uses no expert knowledge. Instead it employs statistical measures to evaluate the spatial associations between known deposits and predictor maps to establish weights for each predictor layer then combines these layers into a predictive map using a Weights of Evidence (WofE) approach.Application of a mineral systems approach in the manual analysis and the fuzzy analysis is critical: potential high value targets identified by these approaches in the western GTO lie largely under cover, whereas traditional manual targeting is biased to areas of outcrop or sub-crop amenable to direct detection technology such as exploration geochemistry, and therefore towards areas that are data rich.The results show the power of combining the three approaches to prioritize areas for exploration. While the manual analysis identifies and employs human intuition and can see through incomplete datasets, it is difficult to filter out human bias and to systematically apply to a large region. The fuzzy method is more systematic, and highlights areas that the manual analysis has undervalued, but lacks the intuitive power of the human mind that refines the target by seeing through incomplete datasets. The empirical WoE method highlights correlations with favorable host stratigraphy and highlights the control of an early set of structures potentially undervalued in the knowledge driven approaches, yet is biased due to the incomplete nature of exploration datasets and lack of abundant gold deposits due to the extensive cover.The results indicate that the most prospective areas for orogenic gold in western GTO are located in the central part of the study area, largely in areas blind to previous exploration efforts. According to our study, the procedure to follow should be to undertake the analyses in the following order: manual prospectivity analysis, followed by the conceptual fuzzy approach, followed by the empirical GIS-based method. Undertaking the manual analysis first is important to prevent explorationists from being biased by the automated GIS-based outputs. It is however emphasized that all of the prospectivity outputs from these three methods are possible, and they should not be treated as ‘treasure maps’, but instead, as decision-support aids. Therefore, a final manual prospectivity analysis redefined by the mutual consideration of output from all of the methods is required.The strategy employed in this study constitutes a new template for best-practice in terrane- to camp-scale exploration targeting that can be applied to different terranes and deposit types, particularly in terranes under cover, and provides a step forward in managing uncertainty in the exploration targeting process.  相似文献   

10.
A Mamdani-type fuzzy inference system for prospectivity modeling of mineral systems is described. The system is a type of knowledge-driven symbolic artificial intelligence that is transparent, intuitive and is easy to construct by geologists because they are built in natural language and use linguistic values. No examples are used for training the system and expert-opinions are incorporated indirectly in terms of objective mathematical functions, which reduce the possibility of over-emphasizing the known deposits usually used as training data. The cognitive reasoning of the exploration geologist is captured in explicit if–then type of statements written in natural language using linguistic values. Conditional dependencies in the exploration data sets are managed through the use of fuzzy operators. A case study for surficial uranium prospectivity modeling in the Yeelirrie area, Western Australia, is used to demonstrate the approach. In the output prospectivity map, the SE-NW trending Yeelirrie and E-W trending Hinkler's Well palaeochannels show high prospectivity, while other channels show very low prospectivity ranges. The known surficial uranium deposits fall in high prospectivity areas, although minor showings and anomalies in the southern part of the study area fall in low prospectivity areas. A comparison of the prospectivity model with the radiometric image shows that several channels showing high surface uranium concentrations in the NW and NE quadrants may not be prospective.  相似文献   

11.
西秦岭李坝金矿床地质、同位素地球化学及其成因探讨   总被引:1,自引:0,他引:1  
李坝金矿床位于西秦岭造山带中的礼-岷矿集区内,赋矿围岩为泥盆系浅变质细碎屑岩,矿床产于中川岩体的外侧热接触变质带内,矿体主要受断裂破碎带控制.本文在李坝金矿床地质特征研究的基础上,对赋矿围岩、花岗斑岩岩脉、矿石硫化物进行了LA-MC-ICPMS原位微区硫同位素测试及化学溶样法分析,对不同地质体的铅同位素进行了系统测定与...  相似文献   

12.
西藏铁格隆南铜(金)矿床三维模型分析与深部预测   总被引:1,自引:1,他引:0  
于萍萍  陈建平  王勤 《岩石学报》2019,35(3):897-912
铁格隆南铜(金)矿床是近年来在班公湖-怒江成矿带西段多龙矿集区新发现的超大型Cu(Au-Ag)矿床。本文针对铁格隆南矿区深部找矿问题,以现代成矿地质理论和多元地学信息综合分析技术为支撑,以构建矿床找矿模型为指导,依托数据库技术、3S技术、三维建模与可视化技术及地质统计学理论与方法,开展基于矿产地质、地球物理、地球化学等成矿条件及找矿标志的三维地质实体建模与矿化异常三维空间重构,将铁格隆南矿床的预测评价研究拓展到三维空间,揭示了区内成矿地质特征、地球化学及地球物理异常表征,据此探讨了矿床的成因及矿体分布特征。并在此基础上,开展了矿区的地质-地球化学-地球物理综合信息分析与预测评价,以期减少单一信息多解性和成矿条件不确定性,为铁格隆南矿区深部找矿工作提供参考。研究结果表明:在地质找矿模型指导下,基于深部成矿空间三维结构重构基础上的三维地质、地球物理、地球化学异常信息提取与综合分析,可以有效的识别成矿地质体和矿致异常信息,实现深部矿产资源靶区空间定位预测,为深部找矿预测研究提供了新思路。综合分析结果显示铁格隆南矿床深部找矿潜力巨大。  相似文献   

13.
黑刺沟金矿床以富As和Sb的微细浸染蚀变岩型金矿化和部分石英脉型锑-金矿化为特征,典型矿物组合为黄铁矿-毒砂(辉锑矿)-石英;贾公台金矿床以少硫化物石英脉型金矿化和蚀变岩型金矿化为特征,As和Sb的质量分数不高,典型矿物组合为黄铁矿-自然金(方铅矿)-石英-钾长石;鸡叫沟金矿床以蚀变岩型金矿化为主,次之为石英脉型金矿化,典型矿物组合为黄铁矿-黄铜矿-石英.3个金矿床的成因均与岩浆岩有密切联系,但各矿区的岩浆岩在岩石学、岩石化学、微量元素及稀土元素特征具有差异,表明其成因不尽相同.这可能是造成3个金矿床地质特征差异的主要原因.  相似文献   

14.
冯守忠 《地质与资源》1998,7(4):288-292
海沟金矿床具有多源、多期、多阶段成矿特点,成矿主要与燕山早期花岗闪长岩及闪长玢岩有关.成矿物质主要来自中元古界色洛河群,也有部分来自岩浆岩.成矿水为岩浆水和大气降水的混合.成矿热源为燕山期花岗闪长岩.成因类型应属混合岩化热液型铀金大型矿床.  相似文献   

15.
320铀矿床隐爆成矿特征及其找矿意义   总被引:2,自引:0,他引:2  
肖晋  郑福瑞 《铀矿地质》1994,10(5):285-293
320铀矿床控矿地质体是一种由岩浆气液隐爆作用所形成的硅质角砾岩体,矿床严格受其控制,属隐爆角砾岩型铀(钼)矿床。同位素组成、稀土元素配分及微量元素等地球化学研究数据表明,成岩成矿物质(除围岩破碎产物外)来源于混合源型岩浆房顶部的"挥-硅岩岩浆体系",成岩成矿作用大体同步。湖南地区以及全国不少地区都存在有与此类似的硅质角砾岩体,因而具十分重要的找矿意义。  相似文献   

16.
冀北金矿的地质特征及找矿方向   总被引:2,自引:0,他引:2  
冀北金矿按其成因类型可划分为层控热液型、热液型、火山型和外生金矿。近东西向深大断裂控制了金矿的空间展布。太古宇迁西群和单塔子群角闪质岩石是金矿的重要矿源层。区域变质作用对金活化、迁移及富集具有决定性作用。海西期超镁铁质及偏碱性侵入杂岩和燕山期火山-侵入岩是金最终富集成矿的重要条件。尚义-赤城-平泉大断裂以南的太古宙表壳岩及其断裂两侧的岩浆岩带是进一步找矿的重点区。中生代火山盆地周边是寻找金矿的新区  相似文献   

17.
山东栖霞庄子金矿床产于郭家岭花岗岩和磁山花岗岩与胶东群的接触带,矿石以石英脉型为主,金品位高且发育明金。庄子金矿矿床地质研究表明,矿区存在两组控矿构造,一组为NNE向,另一组为近EW向。金矿床与郭家岭花岗岩期后热液有成因联系。成矿作用划分为5个阶段,最主要的金矿化阶段为多金属硫化物阶段和细粒黄铁矿—石英阶段。  相似文献   

18.
陈秀法 《地质与勘探》2021,57(6):1191-1202
非洲铀矿资源丰富,在全球占有重要地位,是我国利用铀矿资源的重要来源地。通过分析非洲259处已知铀矿床(点)的地质特征与勘查开发现状,揭示非洲铀矿资源具有分布集中、规模巨大、矿床类型多样等特点,砂岩型、古石英-卵石砾岩型、侵入岩型是最重要的铀矿类型,非洲铀矿主要分布于卡普瓦尔克拉通、新元古代褶皱带的达马拉褶皱带和西非活动带伊勒姆登大型盆地,成矿作用明显受地层、构造、岩浆岩等控制。不同类型矿床成矿时代具有各自特征,古石英-卵石砾岩型铀矿床全部形成于太古宙,侵入岩型铀矿床大多形成于元古宙,砂岩型铀矿床形成时代跨度大,从元古宙到新生代均有产出。近十年来非洲新增铀储量27万吨。建议国内企业抓住机遇,以侵入岩型和砂岩型铀矿为投资重点,加强在纳米比亚和尼日尔等铀矿资源国的勘查开发合作。  相似文献   

19.
A 2D prospectivity model of epithermal gold mineralisation has been completed over the Taupo Volcanic Zone (TVZ), using the weights of evidence modelling technique. This study was used to restrict a 3D geological interpretation and prospectivity model for the Ohakuri region. The TVZ is commonly thought of as a present-day analogue of the environment in which many epithermal ore deposits, such as in the Hauraki Goldfield, Coromandel Volcanic Zone, are formed. The models utilise compiled digital data including historical exploration data, geological data from the Institute of Geological and Nuclear Sciences Ltd. Quarter Million Mapping Programme, recent Glass Earth geophysics data and historic exploration geochemical data, including rock-chip and stream sediment information. Spatial correlations between known deposits and predictive maps are determined from the available data, which represent each component of the currently accepted mineral system model for epithermal gold. The 2D prospectivity model confirms that the TVZ has potential for gold mineralisation. However, one of the weaknesses of this weights of evidence model is that the studies are carried out in 2D, with an approximation of 3D provided by geophysical and drilling data projected to a 2D plane. Consequently, a 3D prospectivity model was completed over the Ohakuri area, constrained by the results of the 2D model and predictive maps. The 3D model improved the results allowing more effective exploration targeting. However, the study also highlighted the main issues that need to be resolved before 3D prospectivity modelling becomes standard practise in the mineral exploration industry. The study also helped develop a work flow that incorporates preliminary 2D spatial data analysis from the weights of evidence technique to more effectively restrict and develop 3D predictive map interpretation and development.  相似文献   

20.
河南省老湾金矿床地球化学特征及矿床成因   总被引:3,自引:0,他引:3  
在详细分析河南省老湾金矿床成矿地质背景、矿床地质特征的基础上,研究该矿床流体包裹体和氢、氧、硫、铅同位素,结果表明该金矿床的成矿流体为中低温、低盐度的富CO2的K+-Na+ -Cl--SO 2-4体系。氧、氢同位素分析显示,成矿流体δ18O值变化于-5.25‰~+5.37‰,δD变化于-67‰~-76‰,表明成矿流体主要来源于岩浆水和大气降水;硫化物的δ34S值变化于-0.1‰~+5.3‰,平均值为+3.98‰,显示深源硫的特征;Pb同位素组成显示铅主要来源于地幔,有少量地壳铅的加入。综合研究表明,老湾金矿床为受韧性剪切带控制的中-低温热液构造蚀变岩型金矿床。   相似文献   

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