Intra-continental Orogeny:Insights from Magnetotelluric Data into the Mesozoic Uplift History of the Eastern Jiangnan Orogen in South China

Despite extensive efforts to understand the tectonic evolution of the Jiangnan Orogen in South China,the orogenic process and its mechanism remain a matter of dispute.Previous geodynamic studies have mostly focused on collisional orogeny,which is commonly invoked to explain the Jiangnan Orogen.However,it is difficult for such hypotheses to reconcile all the geological and geophysical data,especially the absence of ultrahigh-pressure metamorphic rocks.Based on the magnetotelluric data,we present a group of resistivity models produced through the combination of two-dimensional and three-dimensional inversions,revealing the geo-electrical structures of Jiangnan and a typical collisional orogen.In our models,the resistive crust is separated into three parts by a prominent conductive layer with opposite dipping directions on both sides.A special thrust-nappe system,which is different from that developed in a typical collisional process,is revealed in the Jiangnan Orogen.This structure suggests a process different from the simple collisional orogeny.To interpret our observations,an'intra-continental orogeny'is proposed to address the development of the Jiangnan Orogen in the Mesozoic.Furthermore,this'reworked'process may contain at least two stages caused by the decoupling of the lithosphere,which is revealed by an extra conductive layer beneath Jiangnan.

Geochronology and Geochemistry of Ore-related Granitoids in the Giant Gariatong Rb Deposit,Tibet and Implications for Rb Metallogeny in China

Rubidium(Rb)deposits mostly occur in the South China and Central Asia orogenic belts and are often closely associated with highly differentiated granites.This study investigates a newly-discovered giant Rb deposit at Gariatong in the Central Lhasa terrane in Tibet.Detailed field studies and logging data revealed that the Rb mineralization mainly occurs in monzogranite and is related to greisenization.LA-ICP-MS U-Pb dating of zircon yielded ages of 19.1±0.2 Ma and 19.0±0.2 Ma for greisenized monzogranite and fresh monzogranite,respectively.The monzogranites are characterized as strongly peraluminous,with high contents of SiO2,Al2O3,K2O and Na2O as well as a high differentiation index.They are enriched in light rare earth and large ion lithophile elements with significant negative Eu anomalies and depleted high fieldstrength elements.Petrological and geochemical features of these ore-related monzogranites suggest that they are highly fractionated S-type granites,derived from remelting of crustal materials in a post-collisional setting.The geochemistry of zircon and apatite points to a low oxygen fugacity of the ore-related monzogranite during the magma’s evolution.The discovery of the Gariatong Rb deposit suggests that the Central Lhasa terrane may be an important region for rare metal mineralization.

Petrographic, Geochemical and Metallogenical Context of the Geological Formations of the Goumere Region (North-East of Cote D’Ivoire): Implication to the Knowledge of Gold Mineralization

The Gouméré region is located in the North-East of Côte d’Ivoire and is located in the South-West of the Bui furrow. In order to highlight the geology of the area studied, 14 samples were taken for studies using petrographic, geochemical and metallogenic methods. The study of macroscopic and microscopic petrography made it possible to highlight two major lithological units: 1) a volcano-plutonic unit, formed of gabbros, basalt, volcaniclastics and rhyodacite;2) a sedimentary unit (microconglomerate). From a geochemical point of view, the results obtained indicate that the plutonites are gabbro and gabbro diorite while the volcanics have compositions of basaltic andesites, rhyolite and dacites. The sediments have a litharenitic to sublitharenitic character. The metallogenic study made it possible to highlight hydrothermal alterations and metalliferous paragenesis on the formations studied. Hydrothermal alteration is characterized by the presence of carbonation, silicification, sericitization, sulfidation and to a lesser degree chloritization. Metalliferous paragenesis consists of pyrite, chalcopyrite, hematite and magnetite.

Intra-continental back-arc basin inversion and Late Carboniferous magmatism in Eastern Tianshan,NW China:Constraints from the Shaquanzi magmatic suite

The Yamansu belt,an important tectonic component of Eastern Tianshan Mountains,of the Central Asian Orogenic Belt,NW China hosts many Fe-(Cu)deposit.In this study,we present new zircon U-Pb geochronology and geochemical data of the volcanic rocks of Shaquanzi Formation and diorite intrusions in the Yamansu belt.The Shaquanzi Formation comprises mainly basalt,andesite/andesitic tuff,rhyolite and sub-volcanic diabase with local diorite intrusions.The volcanic rocks and diorites contain ca.315-305 Ma and ca.298 Ma zircons respectively.These rocks show calc-alkaline affinity with enrichment in large-ion lithophile elements(LILEs),light rare-earth elements(LREEs),and depletion in high field strength elements(HFSEs)in primitive mantle normalized multi-element diagrams,which resemble typical back-arc basin rocks.They show depleted mantle signature with ε_(Nd)(t)ranging from+3.1 to +5.6 for basalt;+2.1 to+4.7 for andesite;-0.2 to+1.5 for rhyolite and the ε_(Hf)(t)ranges from-0.1 to +13.0 for andesites;+5.8 to +10.7 for andesitic tuffs.We suggest that the Shaquanzi Formation basalt might have originated from a depleted,metasomatized lithospheric mantle source mixed with minor(3-5%)subduction-derived materials,whereas the andesite and rhyolite could be fractional crystallization products of the basaltic magma.The Shaquanzi Formation volcanic rocks could have formed in an intracontinental back-arc basin setting,probably via the southward subduction of the Kangguer Ocean beneath the Middle Tianshan Massif.The Yamansu mineralization belt might have undergone a continental arc to back-arc basin transition during the Late Carboniferous and the intra-continental back-arc basin might have closed in the Early Permian,marked by the emplacement of dioritic magma in the Shaquanzi belt.

Petrogenesis of the～2115 Ma Haicheng Mafic Sills in the Eastern North China Craton and Their Implications for An Intra-Continental Rifting

It is well known that there are widespread igneous events at;100 Ma in the Eastern North China Craton;however,their tectonic environments are controversial.They were thought to be either related to an intra-continental rifting or

STRUCTURAL EVOLUTION AND METALLOGENY OF SOUTH XINJIANG METALLOGENIC BELT,JIANGXI,SOUTH CHINA

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渗出砂岩型铀矿成矿预测与找矿标志

文章基于渗出砂岩型铀矿成矿机理和模式,认为渗出砂岩型铀成矿作用不同于渗入砂岩型铀矿成矿作用,其成矿预测和找矿标志也不同;提出了渗出砂岩型铀矿成矿作用两大基本关键条件识别标志:红杂色含矿建造原生成因和其中控矿灰色砂体的后生成因识别;在提出的红杂色沉积建造中渗出砂岩型铀矿“上红下黑、上下连通、红中找灰、灰中找矿”总体找矿新思路基础上,阐明渗出砂岩型铀成矿区域预测评价条件和标志:深部富铀富有机质沉积岩建造、区域构造、区域建造、放射性异常信息和综合预测标志等,提出并阐述“小凹陷成大矿”条件;系统建立渗出砂岩型铀矿床预测定位标志体系,特别是野外可识别的宏观标志,包括控矿构造、沉积建造、蚀变改造、铀矿化砂岩颜色、外来有机质特征等,并对比了渗入和渗出砂岩型铀成矿预测标志。提出的渗出砂岩型铀矿识别标志体系不仅对区分“渗入”和“渗出”两种矿化成因,而且对厘清控矿要素、指导成矿预测和找矿工程部署具有重要意义和价值。

二连盆地赛汉高毕铀矿床渗出成矿作用和模式

通过探讨二连盆地赛汉高毕铀矿成矿作用,构建铀成矿模式,总结成矿特征,提炼关键控矿要素,可指导矿床外围、深部和类似地区铀矿找矿。文章基于赛汉高毕铀矿床构造、建造、油气演化、铀矿化、铀成矿时代等分析,详细阐述了矿床矿石矿物、矿石元素地球化学特征。确认赛汉高毕铀矿床产于赛汉组上段建造间古河道中,受准宝力格深切断陷、贯通性断裂、赛汉晚期深切河道联合控制,形成透镜状或板状铀矿体,铀成矿作用与区域油气逸散活动、挤压构造活动密切相关;铀矿石中CaO+Al_(2)O_(3)和P_(2)O_(5)与铀含量呈正相关,Co、Ni、Zn含量高,Fe^(2+)/Fe^(3+)总体小于0.8;各类砂岩中酸解烃含量均比较高,Th/U均小于2,表明赛汉组上段原生环境主要为红杂色的氧化环境,灰色含矿砂体主要是渗出还原成因;矿石中铀是以多种铀矿物形式存在,主要有黄铁矿-铀矿物型、地沥青包裹铀矿物型和微粒碎屑铀矿物型。赛汉高毕铀矿床主要为渗出成矿作用,赋存于深部的富含有机质和四价铀的流体沿贯通断裂或高角度不整合和下切河道运移至上部赛汉组上段氧化砂体中,流体被分解形成黄铁矿、富含铁铝等杂质的磷钙铀矿、地沥青,粒径大的地沥青将已先结晶的黄铁矿和富含铁铝等杂质的磷钙铀矿包裹其中,大部分铀矿物就位于较小的地沥青的外侧和附近。

贵州镇宁-紫云泥盆系大型沉积重晶石矿床成矿过程研究

古生代是全球沉积型重晶石矿床成矿的重要时期,这一时期在全球范围内形成了多个大型和超大型重晶石矿。特别是在扬子陆块西南缘的镇宁-紫云地区,发育一个泥盆系大型沉积重晶石矿床,其资源储量逾6000万吨。本文在已有研究基础上,结合最新的野外调查和研究成果,探讨了重晶石成矿过程、成矿规律和关键控矿要素。研究认为,重晶石矿床成矿与甲烷渗漏活动存在成因上的联系。水城-紫云-南丹裂陷槽内次级盆地对矿体的形态和空间展布有重要控制和影响作用。在含矿岩系出露区,矿体明显呈透镜状赋存于上泥盆统响水洞组硅质建造之中,并且显示出从NW至SE厚度不断减薄的规律性变化。结合Sr、S、C、O同位素组成,推断乐纪一带可能更靠近重晶石成矿的中心。甲烷渗漏强度及其消耗途径变化是不同剖面之间重晶石矿体厚度及其共生灰岩的产出特征和数量在空间上存在差异性的主要控制因素。综合研究,将重晶石成矿过程划分为成矿前、成矿期、成矿后三个阶段,并总结了不同阶段的野外识别标志,初步构建了重晶石成矿的理论模型。

离子吸附型稀土矿床的诱导成矿学研究

诱导成矿学的核心理念是针对低品位矿石、尾矿和具有成矿潜力岩石中的关键金属资源,通过人工干预手段诱导目标金属元素活化和富集,在有限的时间尺度内形成具有经济价值的可利用资源。离子吸附型稀土矿床是全球稀土资源的主要来源之一,近年来为全球提供了80%以上的中、重稀土资源供给。该类矿床的形成主要受控于内生稀土初始富集和表生风化淋积成矿两个过程,而后者对于成矿极为关键。由于我国华南地区具有适宜形成离子吸附型稀土矿床的气候条件、大量出露的花岗质岩石及风化壳,因此对该地区开展人工诱导成矿技术研发将具有重要应用前景。通过分析离子吸附型稀土矿床形成的控制因素,预计可选择具有成矿潜力的花岗岩、含稀土风化壳和低品位矿床作为主要诱导成矿对象。通过调控地形地貌、生态、水文和风化壳物理化学条件等加速风化进程,促进稀土元素释放,引导稀土元素定向迁移,并在指定位置进行沉淀成矿,形成具有经济价值的富集稀土的矿体。特别是在该过程中可控制轻重稀土元素的分异,促使其形成富集重稀土的矿体,为解决全球重稀土资源紧缺和保障重稀土资源持续供给提供有效实施方案。因此,对离子吸附型矿床开展诱导成矿学研究具有重要的理论意义和应用价值,可作为诱导成矿学的重点研究方向之一。

阿尔金锂铍花岗岩-伟晶岩成矿规律与资源潜力

阿尔金是原特提斯构造带,曾是锂铍金属成矿研究与找矿的空白区。通过科学分析,研究团队认为阿尔金锂铍研究空白区有找锂铍金属矿床的潜力,并于2018年率先进入阿尔金山无人区开展锂铍成矿作用的调查与研究、并发现多个花岗伟晶岩型锂铍矿床。本文对阿尔金中段地区花岗伟晶岩型锂铍矿床的成矿规律进行了梳理与总结,结果显示:(1)锂铍等稀有金属花岗伟晶岩类型多样,不同类型伟晶岩脉空间上分带,部分伟晶岩脉内部发育丰富的分带结构;(2)锂铍等稀有金属伟晶岩为花岗岩演化的产物,区域上发育有从黑云母花岗岩到二云母花岗岩、白云母花岗岩、钠长花岗岩及电气石伟晶岩、绿柱石伟晶岩、锡石伟晶岩、锂辉石伟晶岩、锂云母伟晶岩与铯沸石伟晶岩的分带结构;(3)花岗岩-伟晶岩成因于变泥砂岩在麻粒岩相变质过程中的黑云母脱水熔融形成的花岗岩浆的结晶分异,是区域构造演化的产物。吐格曼地区的锂铍矿床形成于阿南陆块与阿中陆块的拼贴-碰撞,而位于塔特布拉克花岗岩基两侧的瓦石峡南与塔木切锂铍矿集区的锂铍花岗伟晶岩则形成于三个微陆块的最终碰撞阶段。阿尔金中段地区早古生代花岗岩-伟晶岩发育,成矿条件优越,成矿潜力大,有望成为我国大型锂资源基地。

南岭成矿带中段成矿规律与找矿前景分析

【研究目的 】南岭中段是中国重要的有色金属、能源矿产、非金属和水气矿产资源基地,成矿地质条件优越、矿产类型丰富、成矿作用类型复杂,深入理解其成矿规律是开展区域成矿理论研究和实现找矿突破的关键。【研究方法 】本文基于前人丰硕的成果资料,对南岭成矿带中段成矿规律和找矿方向进行了总结分析。【研究结果 】此次研究明确了南岭中段主要控矿地质条件,厘定了区域两种构造格架体系的控矿作用;依据矿产资源特征,总结了成矿特征、规律及其演化,进一步探讨了区域岩浆演化和成矿潜力;整理出了南岭成矿带中亚带目前发育的50个矿种、872处矿产地和15种矿床类型,并探讨了主成岩作用特征、演化及其成矿潜力。【结论 】南岭中段找矿的主攻方向为:寻找接触带附近的铀矿、煤矿的滑覆构造、受变质和硫铁矿区风化型铁矿、有色金属组合的综合预测和寻找缺位类型,寻找新类型稀有、稀散矿和独立金矿,保护和开发伴生宝石矿。围绕着骑田岭及周边、乐昌—韶关—翁源远景区,有望实现钨锡钼铋铜铅锌铀稀土等矿产的找矿突破。

鄂尔多斯盆地西南部环县地区砂岩型铀矿成矿要素遥感识别

鄂尔多斯盆地是中国重要的能源、矿产产出盆地,先后在盆地北缘发现多个大型砂岩铀矿床,但是在盆内坳陷的铀矿勘查上仍需突破。渗出理论的提出为盆缘找矿向盆内找矿提供了新的理论依据。研究表明:断层、次生还原矿物、磁异常的变化以及地表铀异常信息是渗出成矿作用在浅表的反映。对上述信息的识别可以为盆内砂岩型铀矿勘查提供数据支撑。以鄂尔多斯盆地西南部环县地区为研究区,利用ETM影像、航磁数据进行构造解译,利用ZY1E高光谱影像识别区内主要出露蚀变矿物,结合航磁、航放数据进行综合分析。结果表明:研究区内断层主要表现为NE、NNE走向,其次为NW和SN向,主要出露蚀变矿物为伊利石、碳酸盐岩,主要分布在沿断层与河流下切作用出露的下白垩统岩层中。航磁异常资料显示研究区出现多处磁异常的过渡区,表现为正的弱异常,可能与深部还原性流体的渗出有关。航放数据表明铀的富集与断层、蚀变矿物的分布在空间上有一定关系。综合高光谱影像、航磁航放资料识别出红杂色沉积建造中铀成矿有利的构造与蚀变矿物,在环县地区指出4处找矿有利区,对坳陷内部找矿具有指导意义。

热液体系溶解度实验和热力学计算方法在成矿过程模拟中的应用

热液流体对金属元素的迁移、富集及沉淀成矿起着关键作用,定量刻画金属元素在热液成矿过程中的运移是矿床学研究的重点和难点。以热力学理论为基础,通过开展溶解度实验,揭示金属元素在热液流体中的地球化学行为,是研究金属元素迁移、富集沉淀机制行之有效的重要手段。其中,基于钛合金反应釜开展不同物理化学条件下金属元素在热液流体中的溶解度实验,结合相关的热力学模拟,能够精确测定金属元素在热液流体中的溶解度、络合物配位数、气液两相中的分配系数及相关热力学参数,为定量模拟热液成矿过程提供重要的实验依据。文章归纳了近年来针对热液体系的实验矿床学方法,分析了各类实验方法与分析手段的优点与不足。重点介绍钛合金反应釜溶解度实验和热力学模拟计算方法,并结合该方法模拟钪矿床成矿的水岩反应过程,说明该方法在成矿过程模拟中的应用,最后阐述了其存在的问题,并对该领域未来的研究趋势提出了展望,以期推动该方法在战略性关键金属超常富集机制研究中的应用。

松辽盆地海力锦铀矿床成矿流体特征——来自含矿层砂岩岩石地球化学的证据

松辽盆地西南部砂岩型铀矿床成因是制约盆地西南部铀矿勘查找矿突破的关键因素之一。文章以海力锦铀矿床为研究对象,对其岩石地球化学特征开展了系统研究,主要获得了以下几点认识:1)各地球化学分带砂岩主量元素、稀土元素差别不大,指示含矿层砂岩具有一致的物质来源;但U和Re、Mo、Co、Cr、Pb、Zn、Ni等微量元素在矿石中的含量明显高于原生红色带、弱还原带和中等还原带砂岩,表明铀成矿期发生了这些元素的输入。这些元素通常来自于深部具有一定温度的还原性流体,进一步指示成矿流体可能来自于深部。2)灰色还原带砂岩及矿石中高岭石的含量明显高于原生红色带、弱还原带和中等还原带砂岩,沥青铀矿常吸附于高岭石表面或微孔隙之中,结合研究区姚家期古气候特征及高岭石成因,分析认为灰色还原带砂岩及矿石中异常富集的这部分高岭石为后生成因,与成矿流体关系密切,含矿层砂岩在铀成矿期经历了酸性流体的改造作用。3)结合松辽盆地西南部钱家店地区下白垩统九佛堂组、沙海组广泛分布的富铀烃源岩,认为海力锦铀矿床成矿流体可能来自深部的富铀还原性流体,在成矿期沿连通姚家组下段目标层的断裂向上渗出,随着温度、压力的降低及体系所处环境由还原转变为氧化环境,导致铀在流体中的溶解度急剧降低而析出沉淀下来,最终富集成矿。本次研究为松辽盆地西南部砂岩型铀矿床成因研究提供了新思路,具有重要的理论和实际意义。

Structural Geology and Chronology of Shear Zones along the Shangdan Suture in Qinling Orogenic Belt,China:Implications for Late Mesozoic Intra-Continental Deformation of East Asia

The Shangdan suture zone(SDZ)in the Qinling orogenic belt(QOB)is a key to understanding the East Asia tectonic evolution.The SDZ gives information about convergent processes between the North China Block(NCB)and South China Block(SCB).In the Late Mesozoic,several shear zones evolved along the SDZ boundary that helps us comprehend the collisional deformation between the NCB and SCB,which was neglected in previous studies.These shear zones play an essential role in the tectonic evolution of the East Asia continents.This study focuses on the deformation and geochronology of two shear zones distributed along the SDZ,identified in the Shaliangzi and Maanqiao areas.The shear sense indicators and kinematic vorticity numbers(0.54–0.90)suggest these shear zones have sinistral shear and sub-simple shear deformation kinematics.The quartz’s dynamic recrystallization and c-axis fabric analysis in the Maanqiao shear zone(MSZ)revealed that the MSZ experienced deformation under green-schist facies conditions at∼400–500℃.The Shaliangzi shear zone deformed under amphibolite facies at∼500–700℃.The^(40)Ar/^(39)Ar(muscovite-biotite)dating of samples provided a plateau age of 121–123 Ma.Together with previously published data,our results concluded that QOB was dominated by compressional tectonics during the Late Early Cretaceous.Moreover,we suggested that the Siberian Block moved back to the south and Lhasa-Qiantang-Indochina Block to the north,which promoted intra-continental compressional tectonics.

In situ U-Pb dating and trace elements of magmatic rutile from Mujicun Cu-Mo deposit,North China Craton:Insights into porphyry mineralization

Porphyry Cu(Mo-Au)deposit is one of the most important types of copper deposit and usually formed under magmatic arc-related settings,whilst the Mujicun porphyry Cu-Mo deposit in North China Craton uncommonly generated within intra-continental settings.Although previous studies have focused on the age,origin and ore genesis of the Mujicun deposit,the ore-forming age,magma source and tectonic evolution remain controversial.Here,this study targeted rutile(TiO_(2))in the ore-hosting diorite porphyry from the Mujicun Cu-Mo deposit to conduct in situ U-Pb dating and trace element composition studies,with major views to determine the timing and magma evolution and to provide new insights into porphyry Cu-Mo metallogeny.Rutile trace element data show flat-like REE patterns characterized by relatively enrichment LREEs and depleted HREEs,which could be identified as magmatic rutile.Rutile U-Pb dating yields lower intercept ages of 139.3–138.4 Ma,interpreted as post magmatic cooling timing below about 500℃,which are consistent or slightly postdate with the published zircon U-Pb ages of diorite porphyry(144.1–141.7 Ma)and skarn(146.2 Ma;139.9 Ma)as well as the molybdenite Re-Os ages of molybdenum ores(144.8–140.0 Ma).Given that the overlap between the closure temperature of rutile U-Pb system and ore-forming temperature of the Mujicun deposit,this study suggests that the ore-forming ages of the Mujicun deposit can be constrained at 139.3–138.4 Ma,with temporal links to the late large-scale granitic magmatism at 138–126 Ma in the Taihang Orogen.Based on the Mg and Al contents in rutile,the magma of ore-hosting diorite porphyry was suggested to be derived from crust-mantle mixing components.In conjunction with previous studies in Taihang Orogen,this study proposes that the far-field effect and the rollback of the subducting Paleo-Pacific slab triggered lithospheric extension,asthenosphere upwelling,crust-mantle interaction and thermo-mechanical erosion,which jointly facilitated the formation of dioritic magmas during the Early Cretaceous.Subsequently,the dioritic magmas carrying crust-mantle mixing metallic materials were emplaced and precipitated at shallow positions along NNE-trending ore-controlling faults,eventually resulting in the formation of the Mujicun Cu-Mo deposit within an intracontinental extensional setting.

滇东北地区太阳坝大型沉积型铝土矿的发现及其意义

铝土矿是我国重要的战略性矿产之一,渝南—黔北地区是上扬子陆块内著名的成铝区,与之毗邻的滇东北地区整体处于上扬子陆块南部滇东被动陆缘碳酸盐岩台地,是铝成矿的有利区位,但一直未有突破性发现。近年来,基于1∶1万矿产地质调查,通过地表调查、剖面、探槽、钻探和综合研究等手段,笔者团队首次在滇东北大关太阳坝地区发现了一处大型铝土矿。矿体延伸相对稳定,厚度0.82~30.85 m,平均厚度2.14 m;矿石以硬水铝石为主,归属一水型铝土矿,就平均品位而言,w(Al_(2)O_(3))为59.03%、w(SiO_(2))为19.03%、铝硅比值(A/S)为4.36,估算资源量达到大型规模。矿床从成因上分为原生的沉积型(为主)和次生的堆积型,矿床展布主要受梁山组(P_(2)l)地层沉积时期沉积相带(滨岸沼泽相带)和新寨子向斜构造控制,与相邻的渝南—黔北成铝区具有相似的成矿条件。该发现表明大关地区为一聚铝盆地,从而拓展了上扬子陆块西缘成铝区范围。该项找矿突破势必带动周边铝土矿的勘查,为建设滇东北地区铝资源基地奠定基础,助推滇东北地区形成新的经济支柱产业,促进乡村振兴。

庙垭碳酸岩-碱性岩型铌稀土矿床成矿作用及与国内其他典型矿床对比

稀土元素(REE)和铌(Nb)等战略性关键金属主要赋存在碳酸岩和(或)碱性岩体中。因此,碳酸岩-碱性岩型铌稀土矿床成矿作用研究具有重要的科学意义和经济价值。本文以湖北庙垭碳酸岩-正长岩型铌稀土矿床为例,详细综述了其矿床地质、成岩成矿年代学及矿床模式等方面的相关研究进展,并以“比较矿床学”的方法,将其与国内其他典型碳酸岩-碱性岩型铌稀土矿床进行了对比。通过系统对比,本文指出地幔源区富集组分、岩浆演化程度以及岩浆期后热液流体作用程度的差异是控制碳酸岩-碱性岩型铌稀土矿床成矿差异性的关键因素。庙垭铌稀土矿床由于相对低的热液流体作用程度,稀土品位相对偏低导致稀土资源的经济性偏低。对庙垭铌稀土矿床的开发利用应以其中丰富的铌资源为重点进行攻关,在当前高的铌对外高依存度形势下有望改善我国的铌矿资源格局。

Paleozoic Tectono-Metallogeny in the Tianshan-Altay Region,Central Asia

The research on Paleozoic tectonics and endogenic metallogeny in the Tianshan-Altay region of Central Asia is an important and significant project. The Altay region, as a collision zone of the Early Paleozoic （500-397 Ma）, and the Tianshan region, as a collision zone of the early period in the Late Paleozoic （Late Devonian-Early Carboniferous, 385-323 Ma）, are all the result of nearly N-S trending shortening and collision （according to recent magnetic orientation）. In the Late Devonian-Early Carboniferous period （385-323 Ma）, regional NW trending faults displayed features of dextral strike-slip motion in the Altay and Junggar regions. In the Tianshan region, nearly EW-trending regional faults are motions of the thrusts. However, in the Late Carboniferous-Early Permian period （323-260 Ma）, influenced by the long-distance effect induced from the Ural collision zone, those areas suffered weaker eastward compression, the existing NW trending faults converted into sinistral strike-slip in the Altay and Junggar regions, and the existing nearly E-W trending faults transferred into dextral strike-slip faults in the Tianshan region. The Rocks of those regions in the Late Carboniferous-Early Permian period （323-260 Ma） were moderately ruptured to a certain tension-shear, and thus formed a number of world famous giant endogenic metal ore deposits in the Tianshan-Altay region. As to the Central Asian continent, the most powerful collision period may not coincide with the most favorable endogenic metallogenic period. It should be treated to ＂the orogenic metallogeny hypothesis＂ with caution in that region.