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1.
呼斯特岩体矽卡岩型铜铁矿成矿地质特征及找矿潜力分析   总被引:1,自引:0,他引:1  
论述了呼斯特岩体成矿地质背景,以艾木斯呆依铜铁矿床为例,叙述矽卡岩型铜铁矿成矿地质特征,从岩体成矿地质条件、矿化特征和含矿性出发,指出岩体主攻矿床类型为矽卡岩型,主攻矿种为铁、铜、铅锌、钼、钨,找矿有利地段为岩体南东部凹陷部位,总体找矿潜力较大.  相似文献   

2.
呼斯特岩体位于新疆西天山博罗科努岛弧带中北缘,是博罗科努成矿带东段典型的与矽卡岩矿床成矿有关的中酸性杂岩体。对岩体中的二长花岗岩、花岗闪长岩和暗色包体进行了系统的矿物化学研究,探讨了岩浆的成岩演化过程以及矿物成分与成岩成矿的关系。造岩矿物的化学成分研究表明,呼斯特岩体为典型的I型花岗岩,形成于与俯冲有关的大陆边缘弧环境,成岩物质来自壳幔混源,成岩过程中经历了岩浆混合作用。岩体形成于较高温度(738~770 ℃)、较低压力(057~142 kbar,1 kbar=01 GPa)和高氧逸度环境。二长花岗岩和花岗闪长岩的侵位深度(22~42 km)和高氧逸度有利于可克萨拉—艾木斯呆依铁铜矿床的形成。岩石中的黑云母相对富镁且氧化系数较高,角闪石富镁、富硅且化学成分变化较大,二者均表现出与铁铜矿化有关的成分特征。岩浆混合作用与矿床的形成关系密切,对区内斑岩-矽卡岩型多金属矿床的找矿具有指示意义。  相似文献   

3.
哈勒尕提-木祖克铁铜铅锌矿床是近年来在新疆西天山博罗科努成矿带内发现的一处典型的矽卡岩型铜多金属矿床,目前为中型规模,有达到大型矿床的潜力。矿体赋存于大瓦布拉克岩体与上奥陶统呼独克达坂组(O3h)大理岩、大理岩化灰岩的接触带。成矿受岩浆岩、地层岩性和接触带构造"三位一体"联合控制。大瓦布拉克岩体主要岩性为二长花岗岩和花岗闪长岩,岩石地球化学显示高硅、准铝、低镁、富碱、富钾,为I型花岗岩,富集大离子亲石元素,相对亏损高场强元素,具俯冲带岩浆岩的地球化学特点。呼独克达坂组(O3h)碳酸盐岩地球化学性质活泼且富含铜、锌,有利于含矿热液交代成矿,是区域找矿的优势层位。接触带构造既是成矿地球化学障,又是良好的成矿热液运移通道,直接控制着矿体的产出。  相似文献   

4.
扎色勒库勒铁矿床处于南天山造山带北部,产于下石炭统大哈拉军山组与石炭纪酸性侵入岩接触带矽卡岩中,铁矿床成矿母岩为钾长花岗岩,成矿方式主要为接触交代作用。围岩蚀变强烈,形成各种矽卡岩矿物组合,与磁铁矿关系密切。该矿床成因类型为酸性岩浆与碳酸盐岩地层接触交代形成的矽卡岩型铁矿床。研究对比发现,可利用地层标志、围岩蚀变特征以及物探异常标志等可作为区域性找矿标志。  相似文献   

5.
呼斯特岩体为可克萨拉铁铜矿成矿岩体,由石英闪长岩、花岗闪长岩、二长花岗岩及正长花岗岩组成,时代均为晚泥盆世。岩石SiO_2含量为63.30%~69.16%,具有较高的全碱含量,且总体富钾、贫钠,(K_2O+Na_2O平均值为7.28%;K_2O/Na_2O平均值为1.08),ACNK均值为1.06,属准铝质-弱过铝质高钾钙碱性系列。岩体高LREE/HREE值平均为8.32,弱-中等负Eu异常(δEu=0.45~0.79,平均为0.71),富集大离子亲石元素(LILEs:Rb、Th、K、Zr),相对亏损高场强元素(HFSEs:Nb、Ta、Ti),总体显示火山弧花岗岩特点。矿区未发现与295Ma(辉钼矿Re-Os年龄)配套的具有后造山或是陆内地球化学特征的岩体。因此,呼斯特岩体地球化学特征佐证该岩体年龄仍是目前间接提供可克萨拉铁铜矿成矿时代的唯一依据。区内早二叠世辉钼矿化与可克萨拉铁铜矿化应是2次成矿事件的产物。  相似文献   

6.
哈勒尕提铁铜多金属矿床是新疆西天山北缘博罗科努多金属成矿带上的一个典型矽卡岩矿床,其成岩成矿时代此前尚无确切的年代学资料。作者通过对与成矿相关的二长花岗岩和花岗闪长岩中锆石的LA-ICP-MS U-Pb同位素测定,获得其加权平均年龄分别为(376.4±3.2)Ma和(365.6±3.5)Ma,表明其侵入时代为晚泥盆世,代表了晚古生代北天山洋向南部伊犁板块俯冲消减背景下的岩浆作用产物。矽卡岩矿石中辉钼矿Re-Os等时线年龄为(368.9±3.1)Ma,加权平均年龄为(366±2)Ma,与成岩时代在误差范围内一致。哈勒尕提矿床与同一成矿带上的艾木斯呆依"可克萨拉铁铜矿床、莱历斯高尔-3571铜钼矿床等一起,构成了一个与晚泥盆世—早石炭世中酸性侵入岩有关的矽卡岩-斑岩型铁铜钼多金属成矿系统。  相似文献   

7.
界牌W-Cu矿床产于苗儿山-越城岭复式岩体东北部斑状黑云母花岗岩与灰岩接触带的矽卡岩中,是苗儿山-越城岭复式岩体矿集区最大的矽卡岩型W-Cu矿床。矿区出露的主要岩体为斑状黑云母花岗岩及后期浅色花岗岩体,矿区外围则大面积出露斑状黑云母二长花岗岩。矿化产于斑状黑云母花岗岩与灰岩接触带矽卡岩,及斑状黑云母花岗岩中灰岩捕虏体矽卡岩化带中。黑云母花岗岩发育花岗岩型钨矿床成矿早期常见的钠长石化、云英岩化及从岩体至外接触带蚀变矿物组合显示形成温度逐渐降低。这些现象表明斑状黑云母花岗岩与矿床具有紧密成因联系。本文获得矿区斑状黑云母花岗岩、斑状黑云母二长花岗岩和浅色花岗岩体锆石LA-ICP-MS U-Pb年龄分别为:422±11 Ma,428±7 Ma,410±7 Ma,表明界牌W-矿床及区内主要岩体均形成于加里东期。本文的同位素年龄及前人报道的苗儿山-越城岭矿集区和华南加里东期与花岗岩有关矿床同位素年龄表明苗儿山-越城岭矿集区W-Mo-Cu矿床成矿主要发生在加里东期和印支期,U矿成矿主要发生在燕山期,华南在加里东期发生了分布广泛、成矿元素组合多样的与花岗岩有关的成矿事件,有很好的找矿前景,今后应加强华南加里东期矿床的找矿工作。  相似文献   

8.
山东省齐河县境内发育有矽卡岩型铁矿,近年来该区铁矿勘查和研究工作取得了较大进展。本文通过对研究区内铁矿勘查研究成果进行统计分析,旨在对其控矿特征和找矿标志进行探讨来促进该区铁矿找矿工作。研究区内铁矿控矿地层为奥陶纪碳酸盐岩和石炭纪-二叠纪碎屑岩地层,成矿地质体为燕山晚期中基性侵入岩体;铁矿体主要赋存于地层和岩体的接触带处,且在碳酸盐岩、碎屑岩地层中和侵入岩体中也赋存有部分铁矿体。区内铁矿体赋存类型多样,其中以接触带赋存式为主,且含有断裂充填式、层间充填式、裂隙贯入式、捕虏体构造式等。铁矿体形态复杂,呈层状、似层状、囊状、透镜状等;矿床典型蚀变分带特征为闪长岩带-蚀变闪长岩带-内矽卡岩带-铁矿体-外矽卡岩带-大理岩化带-灰岩带。该区成矿作用以接触扩散交代作用、接触渗滤交代作用为主,此外还有富矿热液充填作用等。研究区内铁矿找矿标志主要包括地层标志(奥陶纪碳酸盐岩和石炭纪-二叠纪碎屑岩地层)、岩体标志(中基性侵入岩体,且发育有钠长石化的蚀变闪长岩)、构造标志(地层与岩体接触带、构造交汇部位、层间滑脱部位、脆性裂隙部位等)、围岩蚀变标志(磁铁矿化、矽卡岩化、钠长石化、蛇纹石化、金云母化等与成矿关系密切)、地球物理标志(明显的高值磁异常和化极磁异常部位、重力异常梯度带和高-低电阻转换带)。在今后铁矿勘查过程中,需要在综合研究该区控矿特征的基础上,可利用多种找矿标志进行相互配合、互为补充和综合研究,以期达到预期勘查效果。  相似文献   

9.
本文以笔者在老挝人民民主共和国万象省赛宋文县爬立山铁矿区开展铁矿产资源勘查评价项目成果为基础,对爬立山铁矿的成矿地质背景、矿床地质特征、地球物理特征、矿床成因、找矿前景等进行了比较详细的研究.结果表明,华力西期为老挝川圹—长山构造带重要的富铁矿成矿期.爬立山铁矿产于华力西期花岗闪长岩与中—上泥盆统灰岩接触带矽卡岩中.矿区矽卡岩发育,已发现的10个原生铁矿体均赋存于花岗闪长岩体与灰岩接触交代形成的矽卡岩带中.矿体形态、产状的变化受矽卡岩体控制.爬立山铁矿为产于华力西期花岗闪长岩围岩接触带中的中高温热液矽卡岩型矿床.该矿为产于花岗闪长岩围岩接触带的矽卡岩、矽卡岩化砂岩和大理岩中的大型铁矿床.在矿区外围找矿潜力巨大.矿体呈脉状、透镜状、似层状.矿体产出部位严格受矿区泥盆系中上泥盆统碳酸盐岩、钙质砂岩层位及北东、北北西向及北西向断层破碎带的控制.容矿岩石主要为中—上泥盆统矽卡岩、矽卡岩化灰岩、大理岩和钙质砂岩.矿石矿物主要以磁铁矿、赤铁矿为主,次为褐铁矿及少量黄铜矿、黄铁矿;脉石矿物主要为方解石、石英、透辉石、透闪石、石榴子石、绿泥石、绿帘石等.研究表明碳酸盐岩地层、花岗闪长岩的侵入、北西向老挝川圹—长山构造带断层的多期次活动及其后期构造作用形成的北东向断层和东西向断层是区内矽卡岩型铁矿形成的重要控制因素.在综合研究成矿地质条件和磁异常特征的基础上,总结了主要找矿标志和找矿方向,提出矿区磁异常深部及外围尚有矽卡型铁矿找矿潜力.本文的研究成果为区内找矿突破提供了新思路和新资料.为老挝川圹—长山成矿带富铁矿找矿突破奠定了基础.  相似文献   

10.
四川道孚县佐莫那协铁矿床地质特征及控矿因素   总被引:1,自引:0,他引:1  
金灿海 《地质与勘探》2010,46(3):385-391
佐莫纳协铁矿产于炉霍-道孚构造带葛卡花岗闪长岩与结晶灰岩接触带。矿区出露3条矽卡岩带和3个铁矿体,矿体均赋存于花岗闪长岩体与结晶灰岩接触交代形成的矽卡岩带中,矿体形态、产状的变化与矽卡岩体具有一致性。研究认为碳酸盐岩地层、花岗闪长岩的侵入、北西向鲜水河断层的多次活动及其后期走滑剪切作用形成的北东向断层是区内矽卡岩型铁矿形成的重要控制因素。根据成矿条件分析及磁异常显示,矿区深部及外围尚有矽卡型铁矿找矿潜力。  相似文献   

11.
本文对北秦岭马河钼矿区桃官坪中-细粒二长花岗岩和西沟斑状二长花岗岩进行了LA-ICP-MS锆石U-Pb年龄测定,分别获得了157±1Ma(NSWD=13)和153±1Ma(NSWD=14)的谐和年龄,表明其为晚侏罗世侵入体。马河钼矿的形成与这两个侵入体密切相关,据此限定该钼矿床成矿时代略晚于157~153Ma,为侏罗世晚期成矿。桃官坪和西沟花岗岩具有高硅(68.12%~76.33%),富碱(Na2O+K2O=6.35%~10.38%)的特征,K2O/Na2O变化较大(0.91~1.89),A/CNK在0.85~1.14之间,为准铝质-弱过铝质高钾钙碱性系列。微量元素上富集U、Pb、Hf等高场强元素,亏损Rb、Ba、K、Sr、P等大离子亲石元素。稀土元素配分曲线为轻稀土相对富集的右倾型,多数具有弱的负铕异常(δEu=0.5~0.9),少数样品具有弱正铕异常(δEu=1.05~1.08)。与华北地块南缘与钼矿有关的花岗岩相比,二者均具有高硅、高钾、富碱的特征。但马河钼矿区成矿花岗岩比华北地块南缘的稍基性,这可能是导致马河钼矿的矿床规模比华北地块南缘较小的原因之一。  相似文献   

12.
黑龙江河口林场锡多金属矿床位于我国东部大陆边缘完达山陆缘增生带内,锆石ICP-MS U-Pb测年结果显示该矿床的成矿母岩体花岗斑岩形成于121.4±0.5 Ma,属早白垩世晚期,成矿时间略晚于此。地球化学测试结果显示,河口林场花岗斑岩SiO_2含量较高,为61.21%~73.81%,K_2O含量较高,为3.74%~4.61%,Na_2O为0.06%~0.20%,属高钾钙碱性系列的A型花岗岩,形成于伸展背景下。(La/Yb)N-Yb、K/Rb-Rb等微量元素比值图解显示矿体的形成与壳-幔岩浆的混合作用有关。中生代晚期(130~120 Ma)我国东部进入地壳伸展减薄的高峰期,古太平洋板块的持续西向俯冲使区内岩石圈不断增厚发生拆沉,软流圈地幔直接加热下地壳使其部分熔融导致壳幔混合作用的发生,形成的岩浆携带大量成矿物质沿伸展作用形成的空间上侵,并于运移过程中不断萃取沿途围岩中的有用组分,随后就位于三叠纪地层内,岩浆演化晚期,Sn、W等金属元素随流体不断聚集在岩浆房顶部及构造薄弱处,随着温度、压力等物化条件的改变,最终沉淀于岩体与地层的内外接触带成矿。本次研究确定了该矿床为区内发现的首例斑岩型锡多金属矿,与东侧俄罗斯境内的锡霍特-阿林锡多金属成矿省具有良好的亲缘性,为该成矿省在我国境内的延伸部分,其发现为我国东北地区锡矿的探寻工作提供了新的思路。  相似文献   

13.
中天山前寒武纪基底中新发现铁铜矿床   总被引:2,自引:0,他引:2  
陈世平 《矿床地质》2006,25(1):111-12
池西铁铜矿床是近年来新发现的赋存在中天山前寒武纪基底卡瓦布拉克群内的块状硫化物型矿床,具上铁下铜的分带性,在成因上可能与海相火山作用有关。已发现的2个矿体呈层状、透镜状产出,产状与围岩地层一致。该矿床可能是中天山地区卡瓦布拉克群内首次发现的块状硫化物型矿床,对今后在中天山乃至东天山地区寻找与海相火山作用有关的块状硫化物型矿床(尤其是铁铜共生矿床)具有重要的参考意义。  相似文献   

14.
The Pulang (普朗) porphyry copper deposit, located in the southern segment of the Yidun-Zhongdian (义敦-为中甸) island arc ore-forming belt of the Tethys-Himalaya ore-forming domain, is a recently discovered large copper deposit. Compared with the composition of granodiorite in China, the porphyry rocks in this area are enriched in W, Mo, Cu, Au, As, Sb, F, V, and Na2O (K1≥1.2). Compared with the composition of fresh porphyry rocks in this district, the mineralized rocks are enriched in Cn, Au, Ag, Mo, Pb, Zn, W, As, Sb, and K2O (K≥1.2). Some elements show clear anomalies, such as Zn, Ag, Cu, Au, W, and Mo, and can be regarded as pathfinders for prospecting new ore bodies in depth. It has been inferred from factor analysis that the Pulang porphyry copper deposit may have undergone the multiple stages of alteration and mineralization: (a) Cu-Au mineralization; (b) W-Mo mineralization; and (c) silicification and potassic metasomatism in the whole ore-forming process. A detailed zonation sequence of indicator elements is obtained using the variability index of indicator elements as follows: Zn→Ag→Cu→Au→W→Mo. According to this zonation, an index such as (Ag×Zn) D/(Mo×W) D can be constructed and regarded as a significant criterion for predicting the Cu potential at a particular depth.  相似文献   

15.
黑龙江三矿沟Fe-Cu矿床是中亚造山带东段大兴安岭北部裸河-多宝山-三矿沟NW向成矿带中矽卡岩型矿床的典型代表。LA-ICP-MS锆石U-Pb年代学表明,与成矿密切相关的黑云母花岗闪长岩的锆石谐和年龄和238U/206Pb加权平均年岭分别为175.9±1.6Ma和175.9±1.1Ma,二者在误差范围内具有良好的一致性,表明多宝山成矿区在早侏罗世晚期存在一期重要的岩浆-热液成矿事件。三矿沟花岗闪长岩的元素地球化学特征具有岛弧岩浆岩的地球化学亲缘性:岩石富钠(Na2O/K2O=1.39~1.59),准铝质(A/CNK=0.87~0.91),富集轻稀土元素(LREE),(La/Yb)N=8.02~10.45,Eu显示弱负异常(δEu=0.82~0.98),富集大离子亲石元素(LILE,如Rb、Ba、K)和元素地球化学性质活泼的不相容元素(U、Th、Pb),相对亏损高场强元素(HFSE,如Nb、Ta、Zr、Hf、Ti)。Sr-Nd-Pb同位素分析结果表明:三矿沟花岗闪长岩具有低的Sr同位素初始比值((87Sr/86Sr)i=0.7041~0.7045)、高的Nd同位素初始比值((143Nd/144Nd)i=0.512556~0.512576)、正的εNd(t)值(2.8~3.9)、年轻的二阶段亏损地幔模式年龄(tDM2=647~733Ma)和幔源铅同位素组成特征((206Pb/204Pb)t=18.121~18.418;(207Pb/204Pb)t=15.480~15.511;(208Pb/204Pb)t=37.628~37.713),上述同位素地球化学特征均显示花岗闪长质岩浆主要源于亏损地幔源区。结合东北地区区域构造演化和岩体微量元素及同位素组成特征反映该矿床形成于岛弧的构造背景,其形成可能与侏罗纪古太平洋板块的俯冲作用密切相关。  相似文献   

16.
栾川西鱼库隐伏斑岩型Mo-W矿床地球化学及其意义   总被引:1,自引:0,他引:1  
西鱼库大型隐伏斑岩钼-钨矿床是近年来在栾川地区开展深部找矿勘查过程中的新发现。该矿床与南泥湖、上房沟钼矿不同,其矿体主要赋存于斑岩体内部而非岩体外接触带的矽卡岩或角岩中。与南泥湖和上房岩体相比,西鱼库隐伏斑岩体的Si O2、K2O含量略低,具有正Eu异常,表明西鱼库隐伏斑岩体比南泥湖和上房岩体分异程度略低,更接近成矿岩浆中心位置。  相似文献   

17.
The Xiaojiashan tungsten deposit is located about 200 km northwest of Hami City, the Eastern Tianshan orogenic belt, Xinjiang, northwestern China, and is a quartz vein‐type tungsten deposit. Combined fluid inclusion microthermometry, host rock geochemistry, and H–O isotopic compositions are used to constrain the ore genesis and tectonic setting of the Xiaojiashan tungsten deposit. The orebodies occur in granite intrusions adjacent to the metamorphic crystal tuff, which consists of the second lithological section of the first Sub‐Formation of the Dananhu Formation (D2d 12). Biotite granite is the most widely distributed intrusive bodies in the Xiaojiashan tungsten deposit. Altered diorite and metamorphic crystal tuff are the main surrounding rocks. The granite belongs to peraluminous A‐type granite with high potassic calc‐alkaline series, and all rocks show light Rare Earth Element (REE)‐enriched patterns. The trace element characters suggest that crystallization differentiation might even occur in the diagenetic process. The granite belongs to postcollisional extension granite, and the rocks formed in an extensional tectonic environment, which might result from magma activity in such an extensional tectonic environment. Tungsten‐bearing quartz veins are divided into gray quartz vein and white quartz veins. Based on petrography observation, fluid inclusions in both kinds of vein quartz are mainly aqueous inclusions. Microthermometry shows that gray quartz veins have 143–354°C of Th, and white quartz veins have 154–312°C of Th. The laser‐Raman test shows that CO2 is found in fluid inclusions of the tungsten‐bearing quartz veins. Quadrupole mass spectrometry reveals that fluid inclusions contain major vapor‐phase contents of CO2, H2O. Meanwhile, fluid inclusions contain major liquid‐phase contents of Cl?, Na+. It can be speculated that the ore‐forming fluid of the Xiaojiashan tungsten deposit is characterized by an H2O–CO2, low salinity, and H2O–CO2–NaCl system. The range of hydrogen and oxygen isotope compositions indicated that the ore‐forming fluids of the tungsten deposit were mainly magmatic water. The ore‐forming age of the Xiaojiashan deposit should to be ~227 Ma. During the ore‐forming process, the magmatic water had separated from magmatic intrusions, and the ore‐bearing complex was taken to a portion where tungsten‐bearing ores could be mineralized. The magmatic fluid was mixed by meteoric water in the late stage.  相似文献   

18.
Multi-stage igneous rocks developed in the recently discovered Huoluotai Cu-(Mo) deposit provide new insights into the controversial late Mesozoic geodynamic evolution of the northern segment of the Great Xing’an Range (NSGXR). Zircon U-Pb dating suggests that the monzogranite, ore-bearing granodiorite porphyry, diorite porphyry, and granite porphyry in the deposit were emplaced at 179.5 ± 1.6, 148.9 ± 0.9, 146.1 ± 1.3, and 142.2 ± 1.5 Ma, respectively. The Re-Os dating of molybdenite yielded an isochron age of 146.9 ± 2.3 Ma (MSWD = 0.27). The Jurassic adakitic monzogranite and granodiorite porphyry are characterized by high SiO2 and Na2O contents, low K2O/Na2O ratios, low MgO, Cr, and Ni contents, low zircon εHf(t) values relative to depleted mantle, and relatively high Th contents. They were produced by partial melting of a subducted oceanic slab, with involvement of marine sediments in the magma source and limited interaction with mantle peridotites during magma ascent. The Late Jurassic diorite porphyry is characterized by moderate SiO2 contents, high MgO, Cr, and Ni contents, and positive dominated εHf(t) values, indicating it was produced by partial melting of a subduction-modified lithospheric mantle wedge and underwent limited crustal contamination during magma ascent. The early Early Cretaceous adakitic granite porphyry shows high SiO2 and K2O contents and K2O/Na2O ratios, low MgO, Cr, and Ni contents, enriched Sr–Nd isotopic compositions, and slightly positive zircon εHf(t) values, suggesting it was produced by partial melting of thickened mafic lower crust. The NSGXR experienced a tectonic history that involved flat-slab subduction (200–160 Ma), and tearing and collapse (150–145 Ma) of the Mongol–Okhotsk oceanic lithosphere. The period of magmatic quiescence from ca. 160 to 150 Ma was a response to flat-slab subduction of the Mongol–Okhotsk oceanic lithosphere. Crustal thickening in the NSGXR (145–133 Ma) was due to the collision between the Amuria Block and the Siberian Craton.  相似文献   

19.
ABSTRACT

The Dayinsu area is located in the northern part of the West Junggar district near the border between China and Kazakhstan and is an important component of the Central Asian Orogenic Belt (CAOB). The Dayinsu area hosts numerous granitoid plutons in Devonian–Carboniferous volcano–sedimentary strata. The older Laodayinsu and Kubei (345–330 Ma) plutons are located in the west with the younger Bayimuzha and Qianfeng (330–325 Ma) plutons in the east. The whole-rock SiO2 contents of the four granitoid plutons range from 52.22 to 68.42 wt.% and total alkaline contents (K2O + Na2O) range from 4.94 to 9.16 wt.%. The granites are enriched in large ion lithophile elements and light rare earth elements with depletions in Nb, Ta, Ce, Pr, P, and Ti. The plutons are metaluminous with I-type signatures. The geochemistry of the intrusions suggests that they formed in a subduction zone setting, and subsequently underwent fractional crystallization during emplacement, with higher degrees of fractionation in the eastern sector than in the west. Similarities in the geochronology and geochemical characteristics of the granitoid plutons in Dayinsu to those in the Tabei district (west to Dayinsu area) suggest that both districts are part of the Carboniferous Tarbagatay Mountain intrusive event. The early Carboniferous (345–324 Ma) granitoid intrusions in the Tarbagatay Mountain likely formed in an island arc subduction setting during the evolution of the CAOB.  相似文献   

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