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1.
内蒙古大井锡铜多金属矿床流体成矿机理及外围找矿预测   总被引:3,自引:1,他引:2  
大井矿床老区锡铜及老区东部砷铜石英脉矿体是大井矿床的一个矿化中心,从该矿化中心向外,流体均一温度、盐度递减,由老区的Sn、Cu及老区东部As、Cu矿体向外逐渐演化为晚阶段Sn及Cu、Pb、Zn、Ag矿体。老区中心富锡及富铜流体是不同来源的流体,反映了该矿床可能存在不同的多个矿化中心,来自不同矿化中心不同矿化阶段的流体在同一空间叠加成矿。大井矿床西区的西北部预测区细脉浸染状矿体成矿流体与大井矿区脉状矿体的流体完全不同,总体显现了斑岩型流体包裹体的高温-高盐度及流体沸腾的特征。推测大井矿床外围预测区可能是大井矿床另一个矿化中心,其深部可能存在斑岩型矿化的新类型。  相似文献   

2.
安徽铜陵凤凰山铜矿床成矿流体研究   总被引:1,自引:0,他引:1  
以安徽铜陵凤凰山铜矿床为例,通过对成矿流体特征的研究以及碳、氢、氧同位素分析,探讨矿床的成矿机制,分析成矿流体性质以及成矿流体来源。凤凰山铜矿床石榴子石、石英和方解石普遍发育流体包裹体,其类型为V-L型、V-L+S型、V-L富气相型和V型。石榴子石、石英和方解石中的流体包裹体分别集中于3个区,其流体包裹体的温度和盐度区间代表成矿流体演化的3个不同阶段。成矿流体经历了从高温度、高盐度向低温度、低盐度的持续演化过程,与成矿作用阶段基本对应,降温、流体沸腾是导致流体中巨量铜元素卸载的主要因素。氢、氧同位素组成表明成矿流体以岩浆水为主,可能在成矿晚期混有少量大气降水。  相似文献   

3.
秘鲁Don Javier斑岩铜钼矿床流体包裹体特征   总被引:1,自引:1,他引:0  
Don Javier斑岩铜钼矿床位于南美安第斯成矿带中段,秘鲁中南部-智利北部巨型斑岩铜钼金多金属成矿带上,矿区主要出露Yarabamba超群花岗闪长岩岩基和英安斑岩岩体,矿体呈筒状,主要赋存在英安斑岩体及其围岩中,受NW向断裂构造控制。在野外地质调查的基础上,文章对矿床流体包裹体特征进行研究,并结合矿体产出形态特征,对成矿流体来源及演化进行探讨。对黄铁矿-石英和黄铜矿(辉钼矿)-石英2个成矿阶段的石英流体包裹体研究结果表明,成矿阶段矿石中发育富气相-液相、气液两相及含NaCl子矿物三相3种类型的原生流体包裹体,流体包裹体均一温度为287~499℃,含NaCl子矿物包裹体的盐度w(NaCleq)为30%~42%,密度为1.08~1.21 g/cm3,成矿流体属于中高温、高盐度的NaCl-H_2O体系,为岩浆热液来源的成矿流体。流体包裹体特征还表明,流体的沸腾作用是引起成矿流体中矿质发生沉淀富集的重要成矿机制。  相似文献   

4.
西藏冈底斯成矿带达布矿区色日普金矿流体包裹体研究   总被引:1,自引:0,他引:1  
色日普金矿位于西藏冈底斯成矿带中段达布斑岩铜钼矿床外围。本文对该矿床矿体中赋存于含矿石英脉中的流体包裹体进行了岩相学、显微测温、激光拉曼探针以及氢氧同位素分析。研究表明:与成矿有关的流体包裹体可以分为3个大类和5个亚类;流体包裹体均一温度变化范围为117~377℃,流体盐度范围为2.57%~45.59%NaCleqv,成矿流体早期为高温、高盐度的H2O-NaCl-CO2体系,成矿期为中高温、中盐度H2O-NaCl-CO2体系,成矿晚期为中低温H2O-NaCl体系;成矿期流体包裹体气相成分除CO2外,还含少量CH4、N2等。据测温结果估算的成矿压力为120~130 MPa。通过对该矿区石英和硅化脉石英流体包裹体研究得出成矿流体主要来源于大气降水和具有显著岩浆贡献的携带金属成矿物质的热液混合的产物。  相似文献   

5.
西藏甲玛铜多金属矿床流体包裹体特征及地质意义   总被引:1,自引:0,他引:1  
甲玛矿床是位于西藏冈底斯成矿带中段的超大型铜多金属矿床。成矿相关岩体和主矿体中的流体包裹体岩相学、显微测温、激光拉曼探针及扫描电镜/能谱分析结果表明:与成矿有关的流体包裹体主要有富液相、富气相和含子矿物三相包裹体;流体包裹体均一温度变化范围为225~500℃,流体盐度(w(NaCl))平均值为36.2%,成矿流体主要为一种中高温、高盐度的NaCl-H2O体系;气相成分除H2O外,富含CH4、H2S、CO2、N2等不混溶体系。CH4、C2H4、C3H6等有机质的出现,说明成矿物质形成于还原环境中。据成矿压力估算成矿深度为2.2~8.3km,流体密度平均为0.89~0.98g/cm3。结合包裹体中的氢氧同位素测试结果认为,成矿流体主要来源于岩浆水,后期有大气降水的参与。含子矿物多相包裹体与不同气相充填度的液相包裹体、气相包裹体共存,且均一温度相近,而盐度相差很大,表明成矿流体经历了沸腾作用。  相似文献   

6.
广西大厂矿田高峰锡多金属矿床流体包裹体研究   总被引:1,自引:1,他引:0  
赵海  苏文超  沈能平  谢鹏  蔡佳丽  甘文志 《岩石学报》2018,34(12):3553-3566
广西大厂锡多金属矿田是世界著名的锡矿产地之一。矿田内绝大部分锡锌资源量分布在西成矿带的高峰和长坡-铜坑两个矿床之中,其中赋存在中泥盆统生物礁灰岩中的高峰100号体以其品位高(Sn 1. 79%、Zn 10. 1%、Pb 5. 21%、Sb4. 8%、Ag 235g/t)、规模大(矿石量超过1300万吨)而在整个大厂矿田中占据非常重要的地位。本文在扫描电镜-阴极发光(SEM-CL)图像分析的基础上,对高峰锡多金属矿床成矿早期锡石-毒砂-磁黄铁矿阶段和成矿晚期硫化物-硫盐-碳酸盐阶段的流体包裹体岩相学、显微测温学及其气相成分的激光Raman光谱进行了系统研究。结果表明,成矿早期锡石-毒砂-磁黄铁矿阶段石英和锡石中主要发育富含CO2和CH4气相流体包裹体,其均一温度和盐度分别为360~410℃和3%~6%Na Cleqv;成矿晚期硫化物-硫盐-碳酸盐阶段石英中则仅发育气-液两相盐水流体包裹体,具有相对低的均一温度(270~310℃)和盐度(3%~6%Na Cleqv)。石英和锡石的H-O同位素组成指示成矿流体主要来源于岩浆热液。对比矿田内其他矿床,进一步发现高峰矿床富CO2气相流体的盐度(3%~6%Na Cleqv)与拉么矽卡岩型Zn-Cu矿床富CO2气相流体的盐度(7%~9%Na Cleqv)相近,认为高峰矿床与拉么矿床可能具有相同的成矿流体来源,两者均来源于深部岩浆房中分异出的超临界流体。高峰矿床成矿流体可能主要来源于深部矽卡岩阶段富CO2气相流体的压缩和冷却(vapor contraction and cooling)。流体冷却过程可能是锡石-硫化物成矿的主要控制因素。高峰矿床-200m中段以上矿体,锡石和石英中的流体包裹体以富CO2和CH4气相流体包裹体为主,而缺失多子晶流体包裹体组合,推测高峰矿床-200m中段以下可能存在富含成矿金属的高密度卤水,从而形成高品位的锡多金属脉状矿体或矽卡岩型Zn-Cu矿体。  相似文献   

7.
下庄铀矿田流体包裹体地球化学研究   总被引:5,自引:0,他引:5  
对下庄铀矿田不同矿体矿石中的石英、萤石、方解石等脉石矿物进行了系统的流体包裹体测温工作。研究结果表明,下庄铀矿田从成矿早期→成矿期→成矿晚期均一温度明显降低,但流体盐度变化不大,均为低盐度的流体。下庄铀矿田不同矿床均一温度与流体盐度具有相似的变化范围,矿床在中温(187~275℃)与低盐度(NaCl1.6~9.6wt%)条件下形成。  相似文献   

8.
西藏甲玛斑岩成矿系统铜钼元素分离机制探讨   总被引:6,自引:2,他引:4  
西藏甲玛矿床是冈底斯成矿带中东段目前勘查程度最高、第一个规模化开发的超大型斑岩成矿系统,主要由矽卡岩铜多金属矿体、斑岩钼(铜)矿体以及角岩铜钼矿体构成。文章以甲玛矿床角岩矿体和斑岩矿体中典型的"上铜下钼"现象为切入点,借助流体包裹体显微测温、激光拉曼测试、同步辐射X射线荧光分析(SR-XRF)等研究方法,分析了甲玛矿床铜钼矿化阶段成矿流体的物化条件差异及微量元素迁移行为。流体包裹体研究结果表明:铜矿化阶段流体温度(大致在235~451℃,主要集中在340~380℃之间)总体上大于钼矿化阶段流体温度(大致在213~500℃,主要集中在310~360℃之间),但两种成矿流体的盐度大致相似,主要位于18%NaCleqv与30%NaCleqv这两个区间,缺乏盐度中间过渡区,说明成矿流体经历了沸腾作用。激光拉曼显微探针测试结果表明,Cu矿化阶段的流体氧化性较Mo矿化阶段更强,而Mo矿化阶段流体略呈还原性。单个流体包裹体同步辐射X射线荧光分析显示,Cu、Au、Fe、Mn、S、As等元素主要在气相中广泛分布,而Mo则主要残留在液相中迁移富集。因此,本文认为甲玛矿床中角岩型和斑岩型矿体呈现"上铜下钼、早铜晚钼"现象,主要由铜、钼元素本身的物化性质,含矿岩浆性质和侵位顺序与深度,以及含矿岩浆后期所分异出的成矿流体的氧化还原性以及其中S含量的差异所致。  相似文献   

9.
辽宁肖家营子矽卡岩型钼(铁)矿床高盐度流体特征及演化   总被引:2,自引:1,他引:1  
肖家营子矿床是一个与中-基性侵入岩有关的矽卡岩型钼(铁)矿床,矿体主要赋存于矽卡岩体中。流体包裹体研究表明,辉钼矿化阶段以含子矿物包裹体和气液两相包裹体为主,含子矿物包裹体通过子矿物最终消失而均一,均一温度为203-440℃,盐度(NaCleq)为32.0%~52.0%,气液两相包裹体通过气泡消失而均一,均一温度为146~340℃,盐度(NaCleq)为4.3%-18.4%;石榴石矽卡岩阶段和磁铁矿化阶段主要为含子矿物包裹体,含子矿物包裹体通过气泡消失而均一,包裹体均一温度分别为505~560℃和435-541%,盐度(NaCleq)分别为43.4%-50.0%和44.9%~56.9%。流体包裹体特征和氢氧同位素分析表明,肖家营子矿床含矿流体由含一定金属成矿元素的高温、高盐度的岩浆热液和低温、低盐度的地层水或大气水组成。成矿早期为含一定金属成矿元素的高温、高盐度流体,这类流体是在降压、降温的过程中由岩浆热液演化而成;辉钼矿阶段流体为中温、高盐度流体和中.低温、低盐度的混合流体。含矿流体在演化的过程中,高温、高盐度流体由于压力和密度的转化对磁铁矿沉淀富集具有重要影响;中温、高盐度与低盐度流体的混合有利于辉钼矿富集成矿。  相似文献   

10.
陈涛亮  任志  冷成彪  王安东 《地质学报》2023,97(6):1900-1916
铜厂和富家坞矿床是德兴矿田中两个典型的斑岩铜矿床,二者成矿时代、成矿背景和致矿斑岩均较一致,但前者中辉钼矿的Re含量明显高于后者。为探究成矿流体演化过程对辉钼矿中Re含量差异的影响,本文对铜厂和富家坞不同成矿阶段的石英开展LA- ICP- MS微区原位分析以及流体包裹体测温研究。结果显示,二者流体均具有由高温向低温,中低盐度高盐度共存向低盐度演化的趋势,且温度下降、流体沸腾以及pH值的变化可能是导致Cu、Mo沉淀的主要原因;但就同一成矿阶段而言,铜厂比富家坞成矿温度更低,并且在主成矿阶段,铜厂具有更高的流体盐度;因此,推测温度和盐度可能是导致二者中辉钼矿Re含量差异的主导因素。  相似文献   

11.
Abstract: The Anle Sn‐Cu and Huanggangliang Fe‐Sn deposits have been exploited in the Linxi district, which is located 165 km northwest of Chifeng City in northern China. In this study the formation mechanisms of the tin deposits in the Anle and Huanggangliang mining area were investigated to understand the mechanisms of tin mineralization in northern China. The veins of the Anle deposit are divided into cassiterite–quartz–chlorite veins, chalcopyrite‐bearing quartz veins, cassi–terite–chalcopyrite–bearing quartz veins and sphalerite‐quartz veins. The sequence of mineralization is tin mineralization (stage I), copper mineralization (stage II), and lead‐zinc mineralization (stage III). The Huanggangliang tin deposit consists of magnetite skarn orebodies and many cassiterite‐bearing feldspar–fluorite veins and veinlets cutting the magnetite orebodies. The fluid inclusions in quartz and fluorite in ores from the Anle and Huanggangliang tin deposits are divided into two‐phase fluid inclusions, vapor‐rich fluid inclusions and poly‐phase fluid inclusions. The final homogenization temperatures of fluid inclusions of quartz in the ores of the Anle deposit and fluorite of tin‐bearing feldspar veins in the Huanggangliang tin deposit range from 195 to 425C and from 215 to 450C, respectively. The fluids responsible for the Anle and Huanggangliang tin deposits were of very high temperature and NaCl‐rich ones containing K, Ca, Al, Si, Ti, Fe and Cl in addition to ore metals such as Sn and Cu. The temperature and chemical composition of fluid in fluid inclusions of igneous rocks in the mining area are very similar to those of fluid in fluid inclusions in the ores of these deposits. The fluid for these ore deposits had a close relation with the fluid coexisting with melt of Late Jurassic granitic rocks in this mining area. Salinities of fluid inclusions from these ore deposits and granitic rocks in the mining area were estimated to range from 35 to 50 wt % NaCl equivalent. Based on arsenopy‐rite geothermometry and fluid inclusion studies, a fluid containing 40 wt% NaCl (eq.) could be formed by phase separation of fluid having 6 wt% NaCl (eq.) at a temperature of 420 to 500C and a pressure of 0.3 to 0.4 kb. The temperatures and pressures presented above indicate an NaCl‐rich magmatic fluid derived from granitic melt that had intruded into a shallow level of crust caused the Sn–Fe–Cu mineralization of the mining area. The geological relationship between these ore deposits and granitic bodies around the ore deposits, and the similarity of fluids forming these ore deposits and coexisting with granitic melt, suggest that these ore deposits were formed by the activity of fluid derived from granitic melt in Late Jurassic age.  相似文献   

12.
大兴安岭南段发育大井、双尖子山、布金黑、拜仁达坝、维拉斯托等多个具有典型后生特征的热液脉状铅锌银锡多金属矿床。为了查明上述矿床在成矿流体、成矿物质等方面的特征与差异,进而总结大兴安岭南段热液脉状矿床成矿作用特点,本次研究在野外地质调研的基础上,对上述矿床进行了流体包裹体、激光拉曼和氢氧硫同位素的研究,并取得了如下主要的认识:(1)双尖子山银多金属矿床成矿流体属简单盐水体系热液,维拉斯托和布金黑矿床成矿流体属富碳质盐水体系热液,而大井铜矿成矿流体则为含子矿物的不均匀盐水体系热液;(2)大井、布金黑、拜仁达坝和维拉斯托等矿床早期成矿流体均来自于岩浆热液,但布金黑、拜仁达坝和维拉斯托矿床成矿流体在运移过程中明显地受到了大气降水和地层中有机质的影响;(3)大兴安岭南段多数热液脉状多金属矿床矿石硫同位素δ34S值具有岩浆来源特点,个别矿床硫同位素δ34S值偏高可能是由复杂的岩浆源区性质及地层硫混入所引起。总的来说,大兴安岭南段不同热液脉状矿床在物质来源和流体演化方面的差异明显,而这也体现了该区中生代热液成矿作用的多样性和复杂性特点。  相似文献   

13.
荒沟山金矿床为吉南老岭金-多金属成矿带内较具代表性矿床之一,产于元古宇老岭群珍珠门组地层之中,受韧性剪切带构造控制.按地质特征、矿物组合及矿脉之间的穿切关系,将荒沟山金矿床热液成矿作用划分为Ⅰ黄铁矿-毒砂-石英阶段和Ⅱ晚期辉锑矿-乳白色石英两个阶段.系统的流体包裹体岩相学及显微测温研究表明:Ⅰ阶段石英中发育含CO2三相、碳质及气液两相3种类型的原生流体包裹体,成矿流体属不混溶的中低温、低盐度NaCl-H2O-CO2体系热液,在成矿过程中发生过不混溶作用而导致金等有用元素沉淀富集;Ⅱ阶段石英颗粒中主要发育气液两相包裹体,成矿流体属均匀的NaCl-H2O体系热液.碳、氢、氧同位素研究表明,Ⅰ阶段成矿流体主要来源于岩浆热液,Ⅱ阶段流体除继承早阶段的热液外,还有大气降水的混入;δD和δ13CV-PDB值分析结果证明两个成矿阶段流体均与地层发生过较强的水岩反应.矿床成因属于中温岩浆热液矿床.   相似文献   

14.
列廷冈-勒青拉矿床位于西藏冈底斯北缘多金属成矿带东侧,是该成矿带内一个独特的同时发育Pb、Zn、Fe、Cu、Mo五种元素矿化的典型矽卡岩型矿床.对该矿床成矿流体性质研究有助于解决这种具有不同来源属性的多金属共生矿床的成矿机制等科学问题.基于此,选取与Fe-Cu-Mo矿化和Pb-Zn-Cu矿化密切相关的矽卡岩矿物和脉石矿物,系统开展了流体包裹体和碳氢氧同位素研究,结果显示二者的成矿流体来源相同并经历了相似的演化过程.矽卡岩阶段主要发育富液相包裹体,成矿流体具有高温中高盐度特征.成矿期石英硫化物阶段和成矿后期碳酸盐阶段主要发育富液相包裹体和含子晶的多相包裹体,前者成矿流体温度属于中高温范畴,而盐度分为高盐度和低盐度两类;后者成矿流体温度属于中低温范畴,而盐度同样分为高盐度和低盐度两类,研究表明出现两种盐度截然不同的流体是由于沸腾作用造成的.稳定同位素研究结果显示矽卡岩阶段成矿流体主要源于发生过脱水去气作用的残余岩浆水,石英硫化物阶段和碳酸盐阶段均有大气降水的参与.灰岩地层与正常海相碳酸盐岩相比δ18O明显亏损,表明成矿流体在矿区灰岩地层中大规模运移并发生水岩反应,从而在远端矽卡岩带形成铅锌铜矿化.结合前人及本次研究结果,列廷冈-勒青拉矿床Fe-Cu矿化与Pb-Zn矿化为同一时期岩浆活动的产物,但分别与不同属性的岩浆有关.降温冷却、流体混合作用以及pH值的变化是控制列廷冈-勒青拉矿床金属沉淀的重要因素,而成矿温度和岩浆属性的差异是造成成矿元素在空间上分带的主要原因.   相似文献   

15.
Specific features of the fluid regime in ore-magmatic systems located in the southwestern part of the Kavalerovo ore district (Primorye) are considered. One system is accompanied by mineralization of the porphyry copper type (Lazurnoe deposit); the other system, by tin (copper-tin) mineralization of the hydrothermal type (Iskra deposit). It is shown that the magmatic stages of these systems are distinguished mainly by the chlorophile nature of the copper-gold system and the fluorophile nature of the copper-tin system. The well-known distinction of these systems in terms of the redox parameter is confirmed, and its different evolution scenarios in the systems are shown. The results of the study of fluid inclusions in quartz of postmagmatic associations show that the processes of ore formation at the Lazurnoe deposit were characterized by a wide temperature range and the heterogeneity of the mineral-forming environment. The early period was marked by the coexistence of aqueous-saline brines (mainly of Na-Ca-Mg-chloride composition) and low-density fluid inclusions. The late period was dominated by ordinary hydrothermal solutions. The Iskra deposit formed in a relatively narrow temperature range from homogeneous fluids of essentially Na-chloride composition characterized by moderate and low salinity.  相似文献   

16.
显微红外测温是利用红外显微镜研究不透明-半透明矿物的流体包裹体丰度和分布特征,并与冷热台相结合进行流体包裹体显微测温分析的一种有效的新技术。云南会泽超大型富锗银铅锌矿床是分布于川-滇-黔接壤区典型的会泽型(HZT)铅锌矿床。本文以该矿床的闪锌矿、方解石流体包裹体为例,应用显微红外测温技术发现闪锌矿中发育大量流体包裹体,按其相态可分为6类:纯气相(V)、富液相气液两相(L+V)、富气相气液两相(L+V)、纯液相(L)、含子矿物三相(L+V+S)、含CO2三相(LCO2+LH2O+VCO2)包裹体,而在热液方解石中仅发现富液相气液两相(L+V)、纯液相(L)包裹体。闪锌矿中的流体包裹体均一温度集中在2个区间:150~221℃和320~364℃;而盐度变化范围较大,主要集中于3个区间:12.0%~18.0%、5.0%~11.0%、1.1%~5.0%。不同世代闪锌矿流体包裹体均一温度大致反映成矿流体演化的全过程,而方解石流体包裹体均一温度主要反映成矿流体演化的中-晚阶段,而且与脉石矿物(方解石)共生的闪锌矿流体包裹体均一温度也高于方解石包裹体均一温度;反映了闪锌矿流体包裹体较方解石更能反映成矿流体的信息,进一步揭示从早成矿阶段到晚成矿阶段,成矿流体大致经历了中高温-中盐度→中低温-中盐度→中低温-中低盐度的演化过程。通过压力校正后的流体包裹体捕获温度反映了早成矿阶段成矿流体呈中-高温,进一步证实了该矿床并非低温矿床。通过矿床对比研究,不仅反映了该矿床明显不同于典型的MVT铅锌矿床,而且表明了显微红外测温技术为该类矿床成矿流体p T x条件及矿床成因的研究提供了新方法与途径,并将在金属矿床成矿流体的研究领域发挥重要作用。  相似文献   

17.
The Daraloo field is located in the southeast of Iran (Kerman province). It is associated with Oligomiocene diorite/granodiorite to quartz monzonite stocks. Copper mineralization is basically relevant to potassic and phyllic alteration zones. Petrographic and geologic studies imply that mineralization is restricted to two major parts locating in the center and east of district. The larger central mineralization has a northwest–southeast trend perpendicular to the smaller one. Hydrothermal ore fluid formation occurred in relatively deep levels thereafter faulting and fracturing provided appropriate conduits to ascend fluids through shallower depths. Early hydrothermal alteration produced a confined potassic assemblage in the central and eastern parts of the stock. Two main fluid inclusion groups in relationship with alteration ore fluids have been identified. They are liquid-rich inclusions containing solid phases, with high temperatures (257°C to 554°C) and high salinities (31 to 67 wt.% NaCl equiv.), and vapor-rich inclusions with high temperatures and low salinities without any solid phases. These magmatic source fluids are responsible for boiling and also potassic and phyllic alteration zone. They also resulted in the formation of quartz groups I and II veins and chalcopyrite deposition. Propylitic alteration is attributed to a Ca-rich meteoric fluid. Inclusions originated from this fluid are liquid-rich having low temperatures (161°C to 269°C) and low salinities (1 to 13 wt.% NaCl). Mixing descending meteoric water with magmatic fluids reduces considerably the salinity of magmatic fluid. Mixing is also the impetus of leaching copper from potassic to the phyllic zone. It is possible to conclude that all these procedures are controlled by the main faults of district having NW–SE trend. Two fundamental events affecting the mineralization are cooling ore-bearing fluids and magnetite (±pyrite) emplacement. The latter one is formed in potassic and phyllic alteration zone in which copper-bearing fluids have interaction with magnetite minerals and so chalcopyrite minerals have been formed nearby magnetites. Temperature and pressure of hydrothermal fluid differentiation could be applied as a predictive tool to discriminate between barren and productive copper porphyry deposits. A simple comparison of temperature and pressure variations between Daraloo deposit and other copper porphyry deposits located in the same belt of Iran (Sahand-Bazman belt) illuminates that Daraloo system has high range of pressure implying deeper exsolution of hydrothermal fluid. On the other hand, economic mineralization has direct relationship with temperature range of orthomagmatic fluids so that if a deposit has a wide range of high temperature fluids, it could be inferred as a barren deposit. In conclusion, it could be inferred that Daraloo district can be categorized as a sub-economic porphyry deposit. On the other hand, restricted formation of chalcopyrite and the other copper-bearing minerals besides large amounts of magnetite and pyrite can approve obviously the low grade of mineralization in Daraloo district.  相似文献   

18.
金水铜矿床受构造控制,热液成矿标志明显。依据成矿地质背景及矿床地质特征、硫同位素和流体包裹体特征等研究认为,成矿物质来源深部,成矿作用具多阶段,成矿流体具热卤水性质;矿床初步确定为岩浆期后热液脉型铜矿床。  相似文献   

19.
The Piaotang deposit is one of the largest vein-type W-polymetallic deposits in southern Jiangxi Province, South China. The coexistence of wolframite and cassiterite is an important feature of the deposit. Based on detailed petrographic observations, microthermometry of fluid inclusions in wolframite, cassiterite and intergrown quartz was undertaken. The inclusions in wolframite were observed by infrared microscope, while those in cassiterite and quartz were observed in visible light. The fluid inclusions in wolframite can be divided into two types: aqueous inclusions with a large vapor-phase proportion and aqueous inclusions with a small vapor-phase ratio. The homogenization temperature (Th) of inclusions in wolframite with large vapor-phase ratios ranged from 280°C to 390°C, with salinity ranging from 3.1 to 7.2 wt% NaCl eq. In contrast, the Th values of inclusions with small vapor-phase ratios ranged from 216°C to 264°C, with salinity values ranging from 3.5 to 9.3 wt% NaCl eq. Th values of primary inclusions in cassiterite ranged from 316°C to 380°C, with salinity ranging from 5.4 to 9.3 wt% NaCl eq. Th values for primary fluid inclusions in quartz ranged from 162°C to 309°C, with salinity values ranging from 1.2 to 6.7 wt% NaCl eq. The results show that the formation conditions of wolframite, cassiterite and intergrown quartz are not uniform. The evolutionary processes of fluids related to these three kinds of minerals are also significantly different. Intergrown quartz cannot provide the depositional conditions of wolframite and cassiterite. The fluids related to tungsten mineralization for the NaCl-H2O system had a medium-to-high temperature and low salinity, while the fluids related to tin mineralization for the NaCl-H2O system had a high temperature and medium-to-low salinity. The results of this study suggest that fluid cooling is the main mechanism for the precipitation of tungsten and tin.  相似文献   

20.
雪鸡坪铜矿床产于印支晚期石英二长闪长玢岩-石英闪长玢岩-石英二长斑岩复式侵入体内,为一斑岩型铜矿床。矿床形成经历了多阶段热液成矿作用,主要有微细脉浸染状黄铁矿±黄铜矿-石英、细脉状辉钼矿±黄铁矿±黄铜矿-石英及微细脉状贫硫化物-石英-方解石等。流体包裹体岩相学、显微测温、激光拉曼及碳、氢、氧同位素综合研究表明,微细脉浸染状黄铁矿±黄铜矿-石英阶段石英中主要发育含Na Cl子矿物三相及气液两相包裹体,与含矿的石英二长斑岩石英中发育的流体包裹体特征相似,表明成矿流体主要为中高温、高盐度Na Cl-H2O体系热液,可能主要来源于印支期石英二长斑岩侵入体;辉钼矿±黄铁矿±黄铜矿-石英中主要发育含CO2三相及气液两相包裹体,成矿流体为中温、低盐度Na Cl-CO2-H2O体系热液,与前者来源明显不同;贫硫化物-石英-方解石石英中主要发育气液两相包裹体,成矿流体为中低温、低盐度Na Cl-H2O体系热液,推测其可能较多来自于大气降水。因此,雪鸡坪铜矿床为不同来源、不同地球化学性质热液叠加成矿作用的结果。  相似文献   

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