湘东光明萤石矿黑云母花岗岩地球化学特征及其对萤石成矿的启示

光明萤石矿产出于湘东锡田岩体北部,为探究矿区内黑云母花岗岩与萤石成矿的关联,对岩体和萤石矿体进行了系统的地球化学研究,并利用LA-(MC)-ICP-MS对黑云母花岗岩中锆石开展了U-Pb年代学、微量元素及Hf同位素地球化学研究。结果显示,黑云母花岗岩具有高硅(SiO₂=72.62%～77.34%)、高碱(Na₂O+K₂O=6.03%～8.66%)、富铝(Al₂O₃=12.02%～13.83%)特征,A/CNK值介于1.07～1.14之间,为过铝质花岗岩。3个样品低U锆石的²⁰⁶Pb/²³⁸U年龄加权平均值在215～218 Ma之间,指示花岗岩侵位于印支期。矿区黑云母花岗岩印支期—燕山期锆石年龄为237～133 Ma,在230～210 Ma、190～170 Ma、150～130 Ma存在3个较集中的年龄峰期,暗示岩浆侵位后受到热事件影响,推测矿区岩浆活动具有多阶段性。黑云母花岗岩岩体有较强的负Eu异常,且富集大离子亲石元素Rb、Th、U...     

粤北竹筒尖铀矿床特富矿赋矿花岗岩锆石U- Pb年代学、地球化学、Hf同位素及成因研究

竹筒尖铀矿床位于下庄矿田西北部,早年的找矿工作陷入瓶颈,近年来由笔者主持的普查项目在该地区有了新的突破,尤其是富含晶质铀矿的特富矿体的首次发现,为下一步的找矿工作提供了新的方向。竹筒尖铀矿床特富矿体的赋矿围岩为粗粒黑云母花岗岩和细粒黑云母花岗岩。本文对该围岩进行锆石U-Pb年龄、Hf同位素及地球化学组成的测定,结果显示:粗粒黑云母花岗岩和细粒黑云母花岗岩成岩年龄分别为241.1±1.6Ma和233.6±1.4Ma,均属于印支期。化学组成上两者均具有富硅、KNa、强过铝质和低CaO/Na_2O比值等特征。微量元素两者均富集大离子亲石元素Rb和高场强元素Th、U、Ta、Hf,明显亏损Ba、Nb、Sr、Ti等元素,但粗粒黑云母花岗岩具有更加分散的微量元素配分曲线,表明其可能受到交代蚀变的影响。两者均具有较高的稀土总量,轻重稀土分馏明显,稀土配分曲线呈"右倾型",以及明显的Eu负异常(粗粒黑云母花岗岩:δEu=0.212～0.269;细粒黑云母花岗岩:δEu=0.155～0.258)。Hf同位素组成上均具有较低的ε_(Hf)(t)值(粗粒黑云母花岗岩:-10.9～-9;细粒黑云母花岗岩:-12.3～-8.7)和古元古代的模式年龄(粗粒黑云母花岗岩:1951～1834Ma;细粒黑云母花岗岩:2030～1810Ma)。地球化学和同位素特征表明两者均为强过铝质的S型花岗岩,较高的Rb/Sr比值和较低的CaO/Na_2O比值表明两者均主要是由富黏土的泥质沉积岩部分熔融而成。粗粒黑云母花岗岩形成于印支期主碰撞期局部的拉张环境,细粒黑云母花岗岩形成于碰撞挤压环境向后碰撞拉张环境的转换时期。     

川西九龙白台花岗岩地球化学特征、锆石U-Pb年龄和Hf同位素组成及其稀有金属成矿意义

为揭示川西九龙白台花岗岩成因及其与稀有金属成矿的关系,笔者等对白台花岗岩开展了岩相学、岩石地球化学、LA-ICP-MS锆石U-Pb年代学、锆石微量元素地球化学、Hf同位素地球化学测试。结果显示,白台黑云母二长花岗岩具高SiO₂(69.01%～70.55%)、高K₂O(3.86%～4.99%)、高碱(K₂O+Na₂O=7.41%～8.18%),低CaO(1.49%～2.2%)、低MgO(0.44%～0.57%)等特征,里特曼指数σ=2.03～2.43,A/CNK=1.07～1.14,为弱过铝质的高钾钙碱性系列岩石;微量元素特征显示相对富集Rb、K等大离子亲石元素,相对亏损Nb、P、Hf等高场强元素;球粒陨石标准化的稀土元素配分模式为明显的轻稀土富集和重稀土亏损的右倾型。白台黑云母二长花岗岩锆石U-Pb年龄为(213～212)Ma,ε_Hf(t)值为-7.4～-1.1,Hf同位素二阶模式年龄T_DM2为(1.6～1.2)Ga。研究结果表明,白台花岗岩形成于后碰撞伸...     

江西武功山早古生代花岗岩的岩石学、锆石U- Pb和Lu—Hf同位素地球化学特征及其地质意义

武功山造山带位于华夏地块与扬子地块碰撞缝合带南侧,记录了新元古代以来的多次构造运动。本文对其中的黑云母二长花岗岩和二云母二长花岗岩进行了全面的矿物学、岩石地球化学、锆石U-Pb同位素年代学及Lu—Hf同位素研究。LA-ICP-MS锆石U-Pb同位素年代学研究指示武功山黑云母二长花岗岩和二云母二长花岗岩结晶于早志留世(441.6～442.2 Ma)。武功山早志留世花岗岩具有富硅(SiO₂含量为67.43%～73.06%)、富碱(Na₂O+K₂O含量为6.47%～8.46%)、贫钙(CaO=0.78%～2.64%)、贫镁(MgO=0.46%～1.61%)等特征,为强过铝质高钾钙碱性花岗岩(A/CNK=1.09～1.35)。同时,岩相学和地球化学指示岩石属于亚碱性系列,分异程度较低,ΣREE较低,轻重稀土分异程度较高,为S型花岗岩且岩浆源区物相为角闪石+斜长石+石榴子石。结合花岗岩锆石f_Lu/Hf值均小于-0.9,ε_Hf(t)均为负值(-6.7到-4.8),指示岩浆来源于古元古代古老...     

内蒙古巴林右旗胡都格绍荣岩体的年代学、地球化学、Hf同位素特征及构造背景

大兴安岭地区晚中生代的大地构造背景一直存在争议,通过对内蒙古巴林右旗胡都格绍荣岩体进行锆石U-Pb测年、岩石地球化学以及锆石Lu-Hf同位素分析,探讨其形成时代及构造背景.胡都格绍荣岩体主体岩性为似斑状黑云母二长花岗岩,LA-ICP-MS锆石U-Pb测年确定其加权平均年龄为129.9±1.4 Ma(MSWD=0.91),指示其侵位于早白垩世.花岗岩具有高SiO₂、Na₂O、K₂O含量,低CaO、MgO含量,富集Cs、Rb、K、Th、U、Zr,亏损Ba、Sr、P、Ti,轻稀土富集,具明显Eu负异常(δEu=0.35~0.44),10 000×[w(Ga)/w(Al)]为2.08~3.05,表明其为典型的A型花岗岩.Hf同位素分析结果显示,锆石具有正的ε_Hf(t)值(2.24~9.41),Hf两阶段模式年龄为1 030~570 Ma,平均为809 Ma,结合其微量元素特征,认为岩浆来源于新元古代地壳的部分熔融.胡都格绍荣花岗岩指示研究区在早白垩世为伸展构造背景,可能与蒙古-鄂霍茨克洋闭合关系更为密切.      

大别造山带汤池早白垩世富碱侵入岩成因及地质意义

本文对大别造山带北淮阳东段汤池地区早白垩世富碱侵入岩进行岩石学、锆石U-Pb年代学、岩石地球化学及锆石Lu-Hf同位素分析,揭示其成因及地质意义。该套岩石主要由正长花岗岩、石英正长岩和正长斑岩组成,伴有辉绿玢岩发育。锆石U-Pb定年结果显示,辉绿玢岩、正长花岗岩和正长斑岩分别形成于130.3±1.7 Ma、128.4±1.7 Ma和122.3±1.5 Ma,为早白垩世岩浆活动的产物。汤池辉绿玢岩相对贫硅(SiO₂=45.23～56.92 wt.%)和富碱(Na₂O+K₂O=5.24～8.04 wt.%),Mg^#值较高(平均值为48);而其他岩类具有高硅(SiO₂=62.44～77.25 wt.%)、高碱(Na₂O+K₂O=7.97～10.35 wt.%)、低CaO含量以及较高的Ga/Al和FeO^T/MgO比值,与典型的A型花岗岩化学特征相似。辉绿玢岩大多数锆石ε_Hf(t)值变化范围为-6.4...     

内蒙古沙麦钨矿花岗岩岩石地球化学、锆石U-Pb年代学及其地质意义

沙麦钨矿床位于内蒙古东乌旗地区,是该区目前已探明的中型岩浆热液型钨矿床。矿体主要赋存在黑云母二长花岗岩和黑云母二长花岗斑岩中,对这两种花岗质岩石的岩相学、岩石地球化学和LA-ICP-MS锆石U-Pb年代学进行了研究。结果表明,黑云母二长花岗岩锆石U-Pb年龄为135.6±1.6 Ma和136.3±1.8 Ma,黑云母二长花岗斑岩锆石U-Pb年龄为138.6±1.1 Ma,二者侵位时间均为早白垩世。两种花岗质岩体具有富SiO₂(73.73%～78.23%)、高钾钠(Na₂O+K₂O)(7.56%～8.89%)、贫MgO(0.09%～0.20%)、贫CaO(0.51%～0.89%)、贫TiO₂(0.03%～0.12%)的特征,属于过铝质-高钾钙碱性系列;微量元素富集Rb、K、Th和U,相对亏损Sr、Ba、Nb、P和Ti元素,具有强烈的Eu负异常,具有较高的FeO^T含量,较高的FeO^T/MgO和FeO^T/(FeO^T+M...     

青藏高原东北缘茶卡北山地区印支期高分异花岗岩的发现及找矿意义

青藏高原东北缘茶卡北山地区发现了伟晶岩型Li-Be矿床,然而该地区尚未发现与成矿相关的花岗岩类侵入体,这也制约了成矿规律研究与成矿预测的开展。本文报道了茶卡北山地区新识别的阿斯合塔花岗岩的锆石、独居石U-Pb年龄、全岩地球化学、锆石Hf同位素、全岩Nd同位素资料。阿斯合塔岩体由黑云母花岗闪长岩、黑云母花岗岩和含石榴子石花岗岩组成;含石榴子石花岗岩锆石²⁰⁶Pb/²³⁸U年龄分散分布,主要介于248～232Ma,独居石²⁰⁶Pb/²³⁸U加权平均年龄为243.0±1.1Ma和246.3±1.0Ma。岩石具高SiO₂(76.56%～77.70%)和K₂O+Na₂O(7.81%～8.50%),低Fe₂O₃^T(0.50%～0.73%)和MgO(0.003%～0.072%)的特征,分异指数(DI)为94～96,铝饱和指数(A/CNK)为0.98～1.09,为弱过铝质高钾钙碱性系列...     

东昆仑祁漫塔格地区乌兰乌珠尔早古生代花岗岩锆石U-Pb年代学、地球化学及其地质意义

为确定东昆仑祁漫塔格乌兰乌珠尔地区片麻状黑云母花岗岩和二长花岗岩的形成时代、岩石成因、源区性质和构造背景,对该岩石样品进行了锆石U-Pb年代学、地球化学和锆石Hf同位素研究.结果显示:片麻状黑云母花岗岩加权平均年龄为457.5±2.3 Ma,铝饱和指数A/CNK介于0.98~1.02,属准铝质岩石,Na₂O/K₂O比值为0.440~0.625,属于高钾钙碱性系列.二长花岗岩加权平均年龄为422.5±1.6 Ma,铝饱和指数A/CNK介于1.03~1.05,属弱过铝质岩石.二者均具有高硅(SiO₂介于68.93%~74.72%)、高碱(全碱ALK介于6.83%~9.40%)、低磷(P₂O₅小于0.12%)等特征.富集轻稀土元素,亏损重稀土元素,δEu值为0.29~0.70,显示Eu中度负异常.富集Rb、K等大离子亲石元素,亏损Nb、Ta、P、Ti等高场强元素,属于I型花岗岩.二长花岗岩样品的ε_Hf(t)值为-2.2~+1.4,二阶段模式年龄为1 320~1 546 Ma.结合岩石成岩年龄、地球化学特征及区域构造演化认为片麻状黑云母花岗岩(457.5±2.3 Ma)为下地壳部分熔融产物,形成于原特提斯洋向北俯冲导致的局部拉张环境.二长花岗岩(422.5±1.6 Ma)岩浆来源于中元古代新增生的下部地壳熔融产物,形成于碰撞拼贴后的伸展构造环境.      

西藏南木林普洛岗岩体锆石定年和Hf同位素特征及其地质意义

对冈底斯中段南木林县普洛岗乡花岗岩岩体进行了原位锆石LA-ICP-MS U-Pb定年和Hf同位素分析。2个花岗岩样品加权平均年龄分别为(44.3±1.1)和(44.5±1.1) Ma,代表该岩体的岩浆结晶年龄为始新世。岩石地球化学资料显示,花岗岩SiO₂质量分数为60.53％~65.28%,K₂O+Na₂O质量分数为6.53％~7.98%,Al₂O₃质量分数为15.52％~16.13%,铝饱和指数为0.86~0.91,属于准铝质高钾钙碱性系列花岗岩类。花岗岩轻稀土元素相对较富集,具有明显的Eu负异常,微量元素中亏损Nb、Ta、Ti和富集Rb、Th、U、Pb。锆石Hf同位素初始比值ε_Hf(t)值为8.8~11.1,¹⁷⁶Hf/¹⁷⁷Hf 为0.282 994~0.283 060,Hf同位素地壳模式年龄为422~557 Ma,反映了其岩浆来源于新生地壳物质的部分熔融。普洛岗乡花岗岩的形成与新特提斯洋向北俯冲、俯冲板片折返断离有关。     

Geochemistry of the Cornubian tin province

The exposed crust of the Cornubian massif in S.W. England has been systematically sampled, and the rocks analysed for a wide range of major and trace elements. Geochemically this region is highly anomalous, with three elements (boron, lithium, tin) occurring at levels several times higher than the average for other parts of the continental crust. The greatest degree of enrichment is found in the rocks of the Cornubian granite batholith, but it is also present in rocks pre-dating the formation of the batholith. The mineral deposits of Cornubia derive their trace elements from different sources: B and Sn from the granite, and Cu and S from the country rocks.     

Boron in the Bolivian tin belt

Tourmaline alteration and high boron contents are typical features of the magmatic-hydrothermal systems of the Bolivian tin province. The average boron content in melt inclusions of quartz phenocrysts from tin porphyry systems is 225 ppm (1σ-variation range: 110–420 ppm; n=12) and suggests a magmatic boron input to the hydrothermal tin systems, and not shallow post-magmatic leaching of boron from pelitic country rocks. Boron data from melt inclusions correlate positively with cesium, rubidium and arsenic, and negatively with lithium, titanium and zirconium, and define magmatic fractionation trends. The generally high B, As, Cs and Li contents in melt inclusions suggest involvement of pelitic source lithologies undepleted in these fluid-mobile components, i.e. first-cycle metamorphic rocks. Magmatic fractionation modified the trace-element contents within a one-log-unit range. Bulk-rock Nd isotope data (ɛ_Nd−5 to −10) are in agreement with the dominantly intracrustal geochemical signature of the Bolivian tin porphyry systems, but also imply a variable but minor mantle input. The metallogeny of the tin belt is likely a consequence of intracrustal melting of Lower Paleozoic pelitic and slightly carbonaceous source material, combined with an extended magmatic evolution. The long-lived thermal preparation of the root zones of the silicic systems is provided by mafic magma which also leaves a chemical imprint in the form of the hybrid dacitic bulk composition of the tin porphyry systems. Received: 6 August 1998 / Accepted: 19 August 1999     

Tin-bearing minerals at the Furong tin deposit,South China: Implications for tin mineralization

It remains poorly constrained whether remobilization of Sn from granites and prograde skarns plays an essential role in forming economic (skarn-type) tin mineralization. Using both electron probe microanalysis and laser ablation–inductively coupled plasma–mass spectrometry methods, in-situ Sn contents, as well as major elements, were analyzed for numerous silicates and magnetite from fresh granite, altered granite, and skarn at the large Furong Sn deposit (530,000 t Sn @ 0.8% Sn) in the Nanling Range, South China. Hornblende and biotite in fresh granite are the main Sn-bearing phases (Sn = 44–321 ppm), while plagioclase and K-feldspar are poor in Sn (< 5 ppm). In altered granite, tin is hosted mainly by hydrothermal muscovite (299–583 ppm) replacing plagioclase, but rarely by chlorite (mostly <10 ppm) replacing hornblende and biotite. In contrast, most silicates (garnet, diopside, vesuvianite, pargasite and epidote) and magnetite from tin skarn are Sn-rich (47–44,241 ppm), except for Sn-poor phlogopite and scapolite (< 10 ppm). In particular, garnet, pargasite, and epidote reach tin concentrations in the percent range. Tin generally enters the stannous silicates and magnetite through substitutions for octahedral Al^vi and Fe³⁺. Comparisons of Sn contents between magmatic and hydrothermal minerals in granite, prograde and retrograde minerals related to tin skarn indicate that remobilization of Sn from granite and prograde skarn is not a pre-requisite to form tin mineralization.     

芙蓉锡矿田骑田岭花岗岩黑云母矿物化学组成及其对锡成矿的指示意义

芙蓉锡矿田骑田岭复式岩体主要由早阶段角闪石黑云母花岗岩和晚阶段黑云母花岗岩组成.电子探针分析结果表明角闪石黑云母花岗岩中的黑云母属于铁黑云母,黑云母花岗岩中的黑云母属于铁叶云母.相对于黑云母花岗岩,角闪石黑云母花岗岩中黑云母的MgO、TiO2含量偏高,Al2O3含量偏低.矿物化学研究结果显示,角闪石黑云母花岗岩中黑云母的结晶温度、氧逸度(logfO2)分别为680℃～740℃、-16.00～-15.31,黑云母花岗岩中黑云母的结晶温度、氧逸度分别为530℃～650℃、-19.20～-17.50.从角闪石黑云母花岗岩到黑云母花岗岩,岩浆结晶温度和氧逸度逐渐降低.与花岗岩有关的共存流体性质的研究发现,与角闪石黑云母花岗岩共存的热液流体log(fH2O/fHF)fluid,log(fH2O/fHCl)fluid,log(fHF/fHCl)fiuid值分别为4.22～4.39,2.78～3.24,-1.82～-1.73,而与黑云母花岗岩共存的热液流体log(fH2O/fHF)fluid,log(fH2OfHCl)fluid,log(fHF/fHCl)fluid值分别为3.27～3.53,2.85～3.22,-0.75～-0.22,可见与两种岩石类型共存热液流体的性质存在明显差异,且热液中Cl、Sn含量变化与岩浆结晶分异指数呈正相关关系.骑田岭岩体从角闪石黑云母花岗岩到黑云母花岗岩,随着岩浆的演化.岩浆结晶期后分异出的热液流体向富Cl和Sn方向演化.芙蓉锡矿田的成矿流体应主要来源于黑云母花岗岩岩浆结晶期后分异出的岩浆热液.     

锡的地球化学性质与华南晚白垩世锡矿成因

锡在地质过程中表现出亲氧、亲硫和亲铁三重特性。在地幔岩浆过程中,锡是一种中等不相容的金属元素。锡成矿主要与酸性岩浆活动有关,其地球化学性质决定了其成矿主要受源区性质、氧逸度以及挥发分含量、岩浆结晶分异等因素控制。高度结晶分异可使锡在岩浆中进一步富集,是锡成矿相关花岗岩的普遍特征;锡为变价元素,岩浆体系氧逸度影响源区中锡的迁移能力和分离结晶过程中锡的元素行为,还原性岩浆体系有利于锡富集成矿。富含F、Cl和B等挥发组分对锡元素的迁移和富集起积极的作用。全球锡矿床分布与俯冲带关系密切,特提斯和环太平洋构造域是主要蕴藏区。重要的锡成矿事件表现出区域性和阶段性的特征。结合锡的地球化学特性以及锡矿分布特征,我们认为最有利锡成矿的动力学机制是俯冲板片后撤机制。俯冲板片后撤引发深部软流圈地幔上涌,导致强烈的壳幔相互作用,形成低氧逸度、富F、Cl和B等花岗岩,有利于锡成矿。对于华南晚白垩世锡成矿事件,新特提斯洋俯冲板片发生后撤是其成矿地球动力学背景。     

The tin zone: sediment-hosted hydrothermal tin mineralization at Rooiberg,South Africa

The Rooiberg tin field, also known as the Rooiberg Fragment, is located within the western lobe of the Bushveld Complex. The fragment is triangular-shaped, consists of early Proterozoic Transvaal Sequence volcano-sedimentary rocks, and is surrounded by granitoid intrusives of the Lebowa Granite Suite. Practically all the significant tin deposits are hosted by arkoses, located towards the transition with shaly arkoses at the stratigraphic top of the Boschoffsberg Quartzite Member. This stratabound distribution of individual deposits gave rise to the concept of a regionally developed continuous stanniferous zone. On regional scale, the individual deposits are broadly similar and are collectively classified as replacement and open space-filling type. Particular styles of mineralization such as tourmaline pockets/orbicules, disseminated cassiterite, steep and flat dipping sulphidic fractures and hydrothermal carbonate breccias appear to dominate each mine. Petrological and geochemical investigations of four mineralized centres, indicated the presence of a 500–600 m thick stratified zone of pervasively altered clastic sedimentary rocks of possible arkosic precursor composition. Alteration displays a distinct zonal distribution consisting of a grey-green sodic (albitized) foot wall, an approximately 80 m transitional sericitized-tourmalinized sulphidic tin zone and red hematitic potassic hanging wall. The observed zonal pattern and localization of economically significant cassiterite, is explained by the evolutionary path of magmatic stanniferous hydrothermal fluids genetically related to the surrounding acid phase of the Bushveld Complex. Areas of high fracture density, the tectonic focal points, acted as conduits for the ascending reactive fluids. Factors such as fluid-lithostatic pressure equilibration, limited fracture evolution and/or impermeable shaly arkose retarded this ascent. As a result accumulation, lateral spreading of fluid and pervasive alteration occurred over a broad stratified front. Lateral overlapping of these fronts creates the impression of a continuous tin zone. Abundance of geochemical common denominators between the various focal points (mines) supports a shared composition and source for these contemporaneous fluids.     

磷灰石地球化学特征对花岗岩锡成矿能力的指示——以滇西腾冲 梁河锡矿带小龙河锡矿床为例

锡矿床全球空间分布高度不均,成矿与花岗岩密切相关,对花岗岩Sn成矿作用的研究受到学界高度重视。准确示踪岩浆源区和精细刻画岩浆演化过程对理解花岗岩与对Sn成矿之间的关系十分关键。磷灰石作为花岗岩类岩石中常见的副矿物,其化学组成在示踪花岗岩岩浆源区和成岩过程方面有独特优势。本文对滇西腾冲-梁河锡矿带具有代表性的小龙河锡矿床,对矿区内的花岗岩展开磷灰石原位化学成分分析。研究结果表明,小龙河锡矿区的花岗岩为一套高分异花岗岩,显示A型花岗岩特征,主要源于地壳物质熔融,花岗岩形成于相对还原的环境,富F且含有一定量的Cl元素。上述岩石地球化学特征有利于花岗岩浆演化过程中Sn的富集和迁移,说明磷灰石的成分特征可以很好地指示花岗岩浆的成因、演化及其物理化学条件,能有效评价花岗岩的Sn成矿能力。     

大东山锡矿田矿床地质特征及矿床成因

大东山锡矿田矿化类型复杂,其中矽卡岩型锡矿规模大,可分含锡矽卡岩型和硫化物矽卡岩型。岩体区有脉状和面状云英岩产出,前者多具锡矿化,后者具钨矿化。燕山第四期花岗岩是锡(钨)成矿母岩,含SiO274.96%~75.28%,K2O+Na2O7.37%~8.54%,K2O>Na2O,与南岭地区钨锡成矿岩体具有相似的岩石化学特征。锡矿成因类型可划分为接触交代型、侵入岩浆热液型和风化矿床。根据成矿地质条件,认为在接触带寻找硫化物矽卡岩、硫化物型锡矿有较大前景,而在岩体区具有寻找云英岩型钨矿的潜力。     

滇西松山锡矿锡石LA-SF-ICP-MS U-Pb年代学及其对区域锡成矿作用的指示

松山锡矿位于滇西临沧花岗岩基的西北侧。矿体主要赋存于临沧黑云母二长花岗岩与松山组绢云石英片岩接触带矽卡岩以及花岗岩和围岩的裂隙中。由于缺乏精确的成矿年代学数据,在一定程度上限制了对矿床成因的认识,并制约了进一步的找矿勘查工作。本文首次利用LA-SF-ICP-MS微区原位U-Pb同位素测年技术对松山锡矿床矽卡岩型和电气石石英脉型矿石中的锡石矿物开展了 U-Pb年代学研究获得2件锡石样品的~(207) Pb/~(206)Pb-~(238) U/~(206) Pb谐和年龄分别为76.6±1.5Ma和79.6±3.6Ma,说明松山锡矿锡的成矿作用主要发生在晚白垩世,与临沧花岗岩主体侵位时间(三叠纪)明显不同。结合地质特征和前人年代学研究成果本文认为该地区存在明显的晚白垩世锡的成矿事件,研究区下一步的找矿工作应围绕岩体与围岩接触带,以及岩体和围岩中的断裂展开。