共查询到18条相似文献，搜索用时 125 毫秒
1.
结合在实际工作中的体会,提出和讨论了“地球深部包体与成矿关系”这一有意义的研究方向及其先导性科学问题。地球深部包体中镍、金、钼、钨等成矿元素的含量是不均一的,镍和金在地幔岩包体中含量最高,钼在玄武岩及镁铁质麻粒岩包体中最高,而钨在长英质麻粒岩和花岗岩类包体中含量最高。这些反映岩石圈和软流圈以及岩石圈的不同层次中镍、金、钼、钨等成矿元素的含量不均一,分别提供了地壳中镍、金、钼、钨矿床的初始物质来源。这一认识可能给镍、金、钼、钨等金属矿床和矿床集中区的战略预测提供一些新思路。 相似文献
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赣南兴国县张家地钼钨矿床成岩成矿时代及地质意义 总被引：1，自引：0，他引：1
地处EW向南岭成矿带和NE向武夷山成矿带叠置部位的赣南兴国-宁都钨锡矿集区产有多处不同矿化类型的钨锡多金属矿床,但总体研究程度较低。本文基于详细野外地质调查,重点开展了张家地钼钨矿床的高精度成岩成矿年代学研究,并探讨了区域钨锡矿床成岩成矿时空分布及地球动力学背景。张家地钼钨矿化产于花岗岩与震旦纪浅变质细碎屑岩的内、外接触带,包括石英脉型(王泥排矿段)和云英岩型(刘家庄矿段)两种矿化类型。利用SHRIMP锆石U-Pb法,获得张家地钼钨矿区似斑状中细粒黑云母花岗岩的年龄为154.1±1.8Ma;利用辉钼矿Re-Os法,获得王泥排矿段石英脉型矿体的辉钼矿Re-Os等时线年龄为158.4±3.1Ma、加权平均年龄为157.7±1.4Ma,刘家庄矿段云英岩型矿体的辉钼矿Re-Os等时线年龄为161.9±3.2Ma、加权平均年龄为157.9±1.6Ma,厘定矿床成岩成矿时代为晚侏罗世,对应于华南中生代第二次大规模成矿作用。石英脉型和云英岩型矿体中辉钼矿的铼含量均较低(9.58×10-6~22.65×10-6),表明成矿物质以壳源为主;综合分析区域最新年代学数据资料,表明钨锡矿床成岩成矿具多期性,主要集中在240~210Ma、170~150Ma和130~90Ma,以赣南和湘南为中心,钨锡矿床向四周成矿年龄均呈变小趋势。燕山期钨锡大规模成岩成矿作用主要形成于华南中生代岩石圈伸展-减薄时期的侏罗纪板内拉张的地球动力学背景。 相似文献
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中国北方中生代大规模成矿作用的期次及其地球动力学背景 总被引：170，自引：67，他引：170
本文论述了中国北方(包括华北、东北及长江中下游地区)金属矿床的空间分布特点,分析和讨论了主要成矿区带(长江中下游、小秦岭-熊耳山、西秦岭、华北克拉通北缘和大兴安岭南段)及一些大型矿集区(胶东、鲁西和乌奴格吐-甲乌拉)中矿化组合和成矿期次以及地球动力学背景。提出中国北方大规模成矿作用出现在200-160Ma,140Ma左右和120Ma左右三个峰期。通过对中生代地球动力学演化的分析研究,认为三大成矿事件所对应的地球动力学背景分别为后碰撞造山过程、构造体制大转折晚期和岩石圈大规模快速减薄。在200-160Ma时期主要表现为大厚度岩石圈局部伸展有关的岩浆-热成矿,在140Ma左右时期成矿表现为与深源花岗质岩石有关的斑岩-夕卡岩矿床,而120Ma左右时期的成矿是在岩石圈快速减薄过程有大量地幔流体参与成矿作用。 相似文献
4.
雷公嶂钼矿床是赣南地区新发现的一座具中型钼矿找矿前景的独立钼矿床,成矿特征明显区别于赣南已发现的与钨多金属共(伴)生的钼矿床。为确定矿床成矿时代,文章利用高精度ICP-MS辉钼矿Re-Os同位素测年技术,首次获得了雷公嶂钼矿床的辉钼矿Re-Os同位素加权平均模式年龄,为(156.3±1.0)Ma,等时线年龄为(156.9±3.6)Ma,证实了矿床成岩与成矿作用同时发生,形成于南岭地区燕山早期中晚侏罗世(165～150 Ma)。矿床中辉钼矿的w(Re)为6.104×10-6～13.974×10-6,平均为8.507×10-6,结合矿床地质特征和成矿岩体主量元素及Hf同位素等证据,文章认为成矿物质来自地壳,没有地幔物质加入。结合赣南地区成岩与成矿年代学资料,文章认为区内钨钼多金属矿床形成于华南中生代岩石圈大规模伸展-减薄的地球动力学背景。 相似文献
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湘南中生代花岗质岩石成岩成矿的时限 总被引：30，自引：1，他引：29
位于南岭中段的湘南地区,中生代花岗质岩石广泛分布;该区W、Sn、Pb、Zn、Mo、Bi等金属矿床密集产出,很多钨、锡矿床达到大型、超大型规模,且找矿潜力巨大,构成一个世界级的有色金属矿集区。最近大量的同位素年代学研究表明,南岭中段钨、锡、铅锌等金属的成矿是一个爆发性、区域性的地质事件,成矿时间高度集中,成矿时限主要在150~160 Ma之间,与该区主要花岗岩的成岩时间相当吻合;对单个钨、锡矿床而言,其矿区的成岩、成矿存在着一种准同期性,即成矿与矿区花岗岩的成岩基本上是同时的、或稍晚于花岗岩的成岩作用。因此,该区中生代的花岗岩与钨锡成矿作用具有明显的时、空联系。南岭中段花岗岩大规模的侵入和钨、锡等金属的爆发性成矿均形成于一种岩石圈伸展减薄、地壳拉张的构造环境,可能与华南中生代第二幕岩石圈伸展事件密切相关。 相似文献
6.
内蒙古查木罕钨钼多金属矿床辉钼矿Re-Os同位素年龄及其地质意义 总被引：3，自引：0，他引：3
内蒙古克什克腾旗查木罕钨钼矿床是近年新发现的矿床。本文通过5件辉钼矿样品的Re-Os同位素测定与分析,获得模式年龄137.8～139.3Ma,加权平均值为138.8±2.8Ma,对应的等时线年龄为139.3±1.5Ma,表明查木罕钨钼矿床形成于早白垩世,与中国东部燕山期大规模钨钼成矿期一致。查木罕钨钼矿床辉钼矿的铼含量介于0.127～2.317μg/g之间,平均0.875μg/g,表明查木罕矿床成矿物质主要来源于上地壳。结合区域上已有研究成果,早白垩世是西拉木伦钼成矿带一期重要的成矿作用,并与中国东部大规模成矿时限相一致,该期成矿作用发生于中国东部岩石圈减薄构造背景。 相似文献
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8.
胶东乳山金矿蚀变岩中绢云母40Ar/39Ar年龄及其对金成矿事件的制约 总被引：7，自引：1，他引：7
胶东乳山金矿是我国单脉金储量最大的矿床,金的成矿具有多期多阶段的特点。为了研究早期矿化的时代,利用绢云母40Ar/39Ar法测定了乳山金矿含矿脉体旁围岩蚀变带中的绢英岩年龄。结果表明,围岩花岗岩的强烈绢英岩化蚀变年龄为129 Ma,比金发生大规模沉淀的成矿时间早约10 Ma,表明乳山金矿是多期热液成矿事件的产物,但这一事件也发生于120±10 Ma,从而证明乳山金矿与胶东其他地区金矿一样都是在中生代构造机制转折、岩石圈强烈减薄的构造背景下集中成矿的,这为进一步认识乳山金矿的成因机制和成矿动力学背景提供了新的证据。 相似文献
9.
湖南金船塘锡铋矿床辉钼矿Re-Os同位素测年及其地质意义 总被引：18，自引：14，他引：4
湖南东坡矿田位于南岭成矿带的西段,构造位置上处于扬子板块与华夏板块的对接地带,矿田内以千里山岩体为中心,发育一系列与燕山期花岗质岩浆作用有关的超大型、大型和中型钨锡钼铋多金属矿床。金船塘锡铋矿床是东坡矿田内一个以锡铋为主的大型矽卡岩型多金属矿床。本文对该矿床的矽卡岩型矿石中的辉钼矿进行了Re-Os同位素测年。结果显示,辉钼矿Re-Os同位素模式年龄范围为157.2±2.8Ma至162.4±2.4Ma,加权平均值为159.8±2.9Ma,对应的Re-Os等时线年龄为158.8±6.6Ma;这些年龄数据与柿竹园矿床辉钼矿的Re-Os等时线年龄(151.0±3.5Ma)在误差范围内基本一致,亦与区内千里山岩体锆石U-Pb年龄(152±2Ma)接近,指示金船塘Sn-Bi矿床与区内花岗岩具有密切的时间和成因关系。结合区域上已有的研究成果,包括金船塘矿床在内的东坡矿田的成岩成矿作用主要集中在149～161Ma,与南岭地区大规模的钨锡多金属成矿作用时限(150～160Ma)一致;另外,区域上的研究表明,幔源物质广泛参与了湘南钨锡矿集区晚中生代的成岩成矿作用,指示该区中-晚侏罗世爆发式的成岩成矿作用可能是区域地壳拉张-岩石圈伸展减薄背景下,强烈的壳幔相互作用的结果。 相似文献
10.
吉林省晚印支期—燕山期成矿事件年谱的拟建及特征 总被引：4，自引：0，他引：4
吉林省铁、镍、钒、钛、钨、钼、金、银、铜、铅、锌、锑等内生金属矿产主要是晚印支—燕山期成矿事件的产物,已有测年数据拟建的成矿事件年谱所显示的结构特征表明：①、可划分出230～180 Ma、180～130 Ma、130～100 Ma三个时段和六个亚时区;②、180 Ma±、130 Ma±、100 Ma±的三大成矿峰期,均处于早期盆地闭合,新期盆地打开的转换期;③、三大成矿峰期由老而新主矿种由钼—金（银）—铜的演化。上述特征受该地质时期区域构造-岩浆作用和岩石圈的演化所制约。 相似文献
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A review of the geodynamic setting of large-scale Late Mesozoic gold mineralization in the North China Craton: an association with lithospheric thinning 总被引：22，自引：0，他引：22
Abundant gold deposits are distributed along the margins of the North China Craton (NCC). Occurring throughout the Precambrian basement and located in or proximal to Mesozoic granitoids, these deposits show a consistent spatial–temporal association with Late Jurassic–Early Cretaceous magmatism and are characterized by quartz lode or disseminated styles of mineralization with extensive alteration of wall rock. Their ages are mainly Early Cretaceous (130–110 Ma) and constrain a very short period of metallogenesis. Sr–Nd–Pb isotopic tracers of ores, minerals and associated rocks indicate that gold and associated metals mainly were derived from multi-sources, i.e., the wall rocks (Precambrian basement and Mesozoic granites) and associated mafic rocks.Previous studies, including high surface heat flow, uplift and later basin development, slow seismic wave speeds in the upper mantle, and a change in the character of mantle xenoliths sampled by Paleozoic to Cenozoic magmas, have been used to suggest that ancient, cratonic mantle lithosphere was removed from the base of the NCC some time after the Ordovician, and replaced by younger, less refractory lithospheric mantle. The geochemistry and isotopic compositions of the mafic rocks associated with gold mineralization (130–110 Ma) indicate that they were derived from an ancient enriched lithospheric mantle source; whereas, the mafic dikes and volcanic rocks younger than 110 Ma were derived from a relatively depleted mantle source, i.e., asthenospheric mantle. According to their age and sources, relation to magmatism and geodynamic framework, the gold deposits were formed during lithospheric thinning. The removal of lithospheric mantle and the upwelling of new asthenospheric mantle induced partial melting and dehydration of the lithospheric mantle and lower crust due to an increase of temperature. The fluids derived from the lower crust were mixed with magmatic and meteoric waters, and resulted in the deposition of gold and associated metals. 相似文献
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Metallogenic Epoch of Nonferrous Metallic and Silver Deposits in the Jiaodong Peninsula, China and its Geological Significance 总被引：2，自引：1，他引：1
SONG Mingchun WANG Shanshan YANG Lixin LI Jie LI Shiyong DING Zhengjiang 《《地质学报》英文版》2017,91(4):1305-1325
As China's most important gold-producing district,the Jiaodong Peninsula also contains copper,lead-zinc,molybdenum(tungsten),and other nonferrous metal ore deposits,but the space-time and genetic relationships with gold deposits remain uncertain.To investigate the temporal relationship between these nonferrous metal and gold ore deposits,We collected the samples from a number of nonferrous metallic and silver deposits and metallogenetic rock bodies in the eastern Jiaodong Peninsula for isotopic dating.The results show that the Re-Os isotopic model ages of the Lengjia molybdenum deposit in Rongcheng range from 114.5± 1.8 Ma to 112.6± 1.5 Ma,with an average age of 113.6± 1.6Ma;the LA-ICP-MS ~(206)Pb/~(238)U ages of 33 zircons in the sericitization porphyritic monzogranite that hosts the Tongjiazhuang silver deposit in Rongcheng range between 122 Ma and 109 Ma,with a weighted mean age of 116.04± 0.95 Ma;the LA-ICP-MS ~(206)Pb/~(238)U ages of 31 zircons in the copper metallogenic pyroxene monzodiorite that hosts the Kuangbei copper deposit in Rongcheng range from126 Ma to 106 Ma,with a weighted mean age of 116.6± 1.7 Ma;and the LA-ICP-MS ~(206)Pb/~(238)U ages of19 zircons in the pyroxene monzodiorite surrounding the Dadengge gold and multimetal deposit in Weihai range from 113 Ma to 110 Ma,with a weighted mean age of 111.7± 0.6 Ma.All these results indicate that the metallogenic ages of the silver and nonferrous metallic deposits in the Jiaodong Peninsula are in a limited range from 118 Ma to 111 Ma.Previous studies have demonstrated that the isotopic ages of gold deposits in the Jiaodong Peninsula range from 123 Ma to 110 Ma,while Weideshanian magmatism occurred between 126 Ma to 108 Ma.Both these ranges are grossly consistent with the metallogenic ages of silver and nonferrous metallic deposits in this study,suggesting that the large-scale mineralization occurred in the Early Cretaceous when magmatic activities were strong.This epoch may be linked to the lithosphere thinning and the thermo-upwelling extension in eastern China at that time.In addition,field investigation also shows that gold and nonferrous metallic deposits are distributed nearby the Weideshanian granite,with the nonferrous metallic deposits lying within or surrounding the granite pluton and the gold deposits outside the granite pluton.We propose the following mineralization scenario:In the Early Cretaceous,an intensive lithospheric extension induced partial melting and degassing of the metasomatized lithospheric mantle,which resulted in the formation of mantle-derived fluids enriched in metal elements.During the rapid process of magma ascent and intrusion,crust-derived fluids were activated by the magmatic thermal dome and served to further extract ore-forming materials from the crust.These fluids may have mixed with the mantle-derived fluid to form a crust-mantle mixing-type ore-forming fluid.The high-temperature conditions in the center or in contact with the granitic magmatic thermal dome would have been favorable for the formation of porphyry-type,skarn-type,and hydrothermal-vein-type ores,thus forming a series of Mo(W),Cu,and Pb-Zn deposits in the mid-eastern Jiaodong Peninsula.In contrast,the medium-to low-temperature conditions in the periphery of the magmatic thermal dome would have favored the deposition of gold(silver) ores under the appropriate physiochemical and structural conditions.The metallogenic epoch of the molybdenum,copper,and silver deposits,and their spatio-temporal and genetic relations to the gold deposits,as demonstrated in this study,not only provide important insights to the study of regional metallogeny,our understanding of the metallogenesis of the Jiaodong type gold deposit,and the geodynamic background of the large-scale mineralization in the Jiaodong Peninsula,but also have practical value in guiding the mineral exploration. 相似文献
13.
中国东北部陆缘内生金矿床成因类型、成矿时代及地球动力学背景 总被引：2，自引：0，他引：2
中国东北部陆缘是我国内生金矿床较为发育的地区之一,以成矿作用复杂、蕴藏丰富的金资源量倍受国内外地质学家关注。通过对该区内生金矿的地质和成矿年代的系统研究,初步将该区内生金矿床划分为中温热液金矿床、接触交代-热液金矿床、斑岩型/类斑岩型金铜矿床和浅成低温热液金矿床4种主要成因类型和3个重要成矿期（170～160 Ma、130～110 Ma和110～90 Ma）。结合同位素地球化学特征,进一步确定中温热液金矿床的成矿物质主要来自下地壳源,成矿作用与中生代燕山早期古太平洋板块俯冲作用引发的中国东部大陆边缘岩石圈减薄及拆沉的动力学过程密切相关;接触交代-热液金矿床的成矿物质来源于年轻地壳,成矿作用与古太平洋板块俯冲引起的岩石圈减薄拆沉的伸展构造背景下的岩浆接触交代作用更为密切;而斑岩型/类斑岩型金铜矿床和浅成低温热液金矿床的成矿物质来源为壳幔混合源,其成矿发生在古太平洋板块向亚洲大陆正北向俯冲转入Izanagi Farallon板块西向俯冲的构造转换期。 相似文献
14.
海南岛钼矿床Re-Os年龄及其成矿地球动力学背景探讨 总被引：1，自引：0，他引：1
海南岛已发现的钼矿床(点)在空间上或成因上多与北西向或近南北向构造以及燕山晚期侵入的花岗质岩石密切相关。利用辉钼矿Re-Os同位素方法,对海南岛罗葵洞、文且、石门山三个典型的斑岩型钼矿床进行了精确定年,分别获得了99.7±0.4 Ma、104±1.0 Ma、88.6±1.0-80.2±0.6 Ma的成矿年龄,显示海南岛钼矿具有多阶段或多次成矿作用的特点(一次发生于约100Ma,另一次发生于80~88Ma间),形成于大陆边缘岩石圈拉张减薄、软流圈地幔上涌的伸展构造体制。 相似文献
15.
熊耳山—外方山矿集区位于秦岭造山带之华北板块南缘,经历了复杂的碰撞造山过程,成矿时间跨度大,成矿强度高,成矿作用多样。复合造山过程和相应的成矿作用已被深入研究,但成矿系统的划分和叠加成矿作用尚需研究。本文将熊耳山—外方山矿集区发育的Au-Mo矿床划分为造山型Mo矿床、斑岩型Mo矿床、岩浆热液脉型Mo矿床、造山型Au矿床和岩浆热液型Au矿床5个类型,对应5种成矿系统：(1)造山型Mo矿床形成于250~227 Ma的同碰撞环境和227~194 Ma的后碰撞环境,为变质热液萃取壳源Mo成矿;(2)斑岩型Mo矿床形成于163~135 Ma的洋陆俯冲环境和135~116 Ma的岩石圈减薄环境,为岩浆热液携带幔源或壳源Mo成矿;(3)岩浆热液脉型Mo矿床形成于227~194 Ma的后碰撞环境,为岩浆热液携带幔源Mo成矿;(4)造山型Au矿床在三叠纪发生了预富集作用,主要形成于163~135 Ma的洋陆俯冲环境和135~103 Ma的岩石圈减薄环境,为变质热液萃取壳源Au成矿;(5)岩浆热液型Au矿床仅形成于135~103 Ma的岩石圈减薄环境,为岩浆热液携带壳源Au成矿。矿集区主要存在两种叠加成矿作用,即不同构造背景下多种成矿系统的叠加和同一构造背景下不同成矿系统的叠加。 相似文献
16.
Tectonic implications from Re-Os dating of Mesozoic molybdenum deposits in the East Qinling-Dabie orogenic belt 总被引：34，自引：0，他引：34
J.W. Mao G.Q. Xie W.J. Qü H.S. Ye H.M. Li Y.F. Li 《Geochimica et cosmochimica acta》2008,72(18):4607-4626
The East Qinling-Dabie molybdenum belt is part of a larger East-West trending metallogenic belt in eastern China. Most of the molybdenum deposits occur as porphyry or porphyry-skarn type, but there are also some vein type deposits. Following systematic Re-Os dating of molybdenite from 13 deposits and comparisons with two previously dated deposits, we have recognized that the molybdenum mineralization in the East Qinling-Dabie belt was developed during hydrothermal activity linked to magmatism and the emplacement of granitoid stocks. Three pulses of granitoid magmatism and Mo mineralization are recognized corresponding to significant tectonic events in the East Qinling-Dabie belt. Vein type deposits dated at 233-221 Ma were formed in detachment fractures, indicating localized extension within the collisional setting of the North China and Yangtze Cratons. I-type and transitional I- and S-type granites and related mineralization dated at 148-138 Ma may have formed part of a continental magmatic arc, with widespread magmatism and back-arc extension caused by subduction of the Izanagi or Paleopacific plate beneath the Eurasian continent in a WNW-ESE direction in the Late Jurassic-Early Cretaceous. Both S-type and transitional S- and I-type granite-associated porphyry molybdenum deposits dated at 131-112 Ma are part of an extensive mineralization event throughout East China that can be ascribed to regional large-scale lithospheric thinning, delamination and thermal erosion. 相似文献
17.
The link between metallogeny and craton destruction in the North China Craton (NCC) remains poorly understood, particularly the mechanisms within the interior of the craton. In this overview, we summarize the major stages in the history of formation and evolution of the NCC, the spatio-temporal distribution and types of major ore species, as well as mantle contribution to the metallogeny, in an attempt to evaluate the geodynamic settings of metallogeny and the mechanisms of formation of the ore deposits. The early Precambrian history of the NCC witnessed the amalgamation of micro-blocks and construction of the fundamental tectonic architecture of the craton by 2.5 Ga. The boundaries of these micro-blocks and the margins of the NCC remained as weak zones and were the principal locales along which inhomogeneous destruction of the craton occurred during later tectonothermal events. These zones record the formation of orogeny related gold, copper, iron and titanium during the early to middle Paleoproterozoic with ages ranging from 2.5 to 1.8 Ma. The Early Ordovician kimberlite and diamond mineralization at ca. 480 Ma, the Late Carboniferous and Early to middle Permian calc-alkaline, I-type granitoids and gold deposits of 324–300 Ma, and the Triassic alkaline rocks and gold–silver-polymetallic deposits occurring along these zones and the margins of the blocks correlate with rising mantle plume, southward subduction of the Siberian plate and northward subduction of the Yangtze plate, respectively. The voluminous Jurassic granitoids and Cretaceous intrusives carrying gold, molybdenum, copper, lead and zinc deposits are also localized along the weak zones and block margins. The concentration of most of these deposits in the eastern part of the NCC invokes correlation with lithosphere thinning associated with the westward subduction of the Pacific plate. Although magmatism and mineralization have been recorded along the margins and few places within the interior of the NCC in the Jurassic, their peak occurred in the Cretaceous in the eastern part of the NCC, marking large scale destruction of the craton at this time. The junctions of the boundaries between the micro-continental blocks are characterized by extensive inhomogeneous thinning. We propose that these junctions are probably for future mineral exploration targeting in the NCC. 相似文献
18.
Song Yang Tang Juxing Qu Xiaoming Wang Denghong Xin Hongbo Yang Chao Lin Bin Fan Shufang 《地球科学进展》2014,29(7):795-809
The traditional Bangongco-Nujiang metallogenic belt overlap with the ophiolitic melange units remained in the Bangongco-Nujiang ocean including the Cr, Au, Fe mineralization controlled with magma liquation. On the other hand, the broad metallogenic belt involved the deposits which had been recognized the products of subduction or postsubduction lithospheric extension in the northern and southern sides of Bangongco-Nujiang subduction zone, which includes the southern edge of the southern Qiangtang, suture zone, part of the North and Middle Gangdese block. The types of deposits include porphyry copper (gold) deposits, skarn iron (copper) deposits, hydrothermal-altered rock type of gold deposits and hydrothermal type of tungsten deposits throughout the evolution of Bangongco-Nujiang ocean. The copper mineralization has two episodes at about 120~105 Ma and 90~85 Ma, respectively. The early stage of copper mineralization (120~105 Ma) likely formes by remelting of previously subduction-modified arc lithosphere. Moreover, the late stage of copper mineralization (90~85 Ma) could be triggered by postcollisional lithospheric mantle delamination. Some of key fundamental scientific problems, such as Tectonic background (metallogenic environment), magmatism, metallogenic mechanism of typical deposits, the relationship between the preservation and plateau uplift, we need to pay attention to in the future work. 相似文献