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1.
337铀矿床帽峰岩体锆石激光探针U-Pb法年龄及其地质意义   总被引:1,自引:0,他引:1  
帽峰岩体是下庄铀矿田最重要的赋铀矿岩体,准确确定该岩体的成岩年龄和演化历史是正确认识下庄矿田铀成矿作用的关键。本文采用锆石激光探针U-Pb法确定了337矿床范围内帽峰岩体的成岩年龄为238.2±2.3Ma,是印支期岩体,而不是先前认为的燕山期岩体。公认的337矿床铀成矿年龄是138Ma,巨大的矿岩时差表明337矿床不是先前所认为的典型岩浆热液型铀矿床。  相似文献   

2.
江西大湖塘地区近年发现了一批大-特大型钨铜多金属矿矿床,矿床类型均为燕山期构造-岩浆热液型,成矿与燕山期花岗岩有关,基底中的成矿元素被活化并参与成矿;矿化受燕山期断裂及其岩体与围岩接触面的控制,根据岩体形成时代、岩石地球化学特征及与矿化的关系判断,细粒花岗岩及花岗斑岩为成矿岩体或成矿地质体;该区的成矿作用与区域燕山期构造-岩浆热液成矿系统直接相关,并受深部作用过程和浅部构造环境的双重控制;其成矿机理是基于成矿系统内部各种物理、化学(生物)作用的耦合,成矿实际上是深部过程背景与表层岩石响应的结果。  相似文献   

3.
吉林海沟金矿床地质特征及成矿模式   总被引:7,自引:0,他引:7  
冯守忠 《地质与勘探》1999,35(1):10-13,25
海沟金矿床具有多源、多期、多阶段成矿的特点,成矿主要与燕山早期花岗闪长岩及闪长玢岩有关。对其矿床地质特征、同位素地质学、矿床成因及成矿模式等方面研究,认为成矿物质来源具双重性,即有来源于地层,也有部分来自岩浆岩。成矿水为岩浆水和大气降水的混合,成矿热源为燕山期花岗闪长岩。成因类型应属于混合岩化热液型铀金矿床  相似文献   

4.
赣北大湖塘钨铜多金属矿集区特征与成矿作用模式   总被引:1,自引:0,他引:1  
大湖塘矿集区地处扬子陆块—下扬子地块东南缘,钦杭(钦州—杭州)复合造山带中段北侧。区内出露基岩大多数为晋宁期黑云母花岗闪长岩(九岭岩基主体部分),少数为新元古界双桥山群浅变质细碎屑岩(九岭岩基残余顶盖)以及燕山期斑状花岗岩、细粒花岗岩和花岗斑岩。本文在综合研究区域地质、矿床地质成果基础上,分析了该区燕山期构造—岩浆的活动规律,厘定了成矿岩体;运用构造解析的原理分析了该区燕山期构造—岩浆—成矿之间的关系,构建了燕山期构造—岩浆热液成矿作用模式。认为该区特大型钨铜多金属矿的形成与燕山期构造-岩浆热液成矿系统的发生、发展、演化具有密切的成生联系,其中成矿构造与成矿结构面是成矿作用的基础,成矿岩体是成矿作用的关键。成矿是成矿岩体与成矿构造、成矿结构面三位耦合的结果。  相似文献   

5.
吉林正岔铅锌矿床地质特征及成矿机理   总被引:1,自引:0,他引:1       下载免费PDF全文
吉林省正岔铅锌矿床具有多源、多期、多阶段成矿的特点,成矿主要与燕山期花岗斑岩体有关.对矿床地质特征、同位素地球化学特征、成矿机理等的研究认为:成矿物质具有双重来源--地层源与岩浆源,成矿水源为岩浆水和大气降水的混合,成矿热源为花岗斑岩的活动,成因类型为层控夕卡岩型矿床.  相似文献   

6.
江西相山矿田西北部与东南部矿床侵蚀程度的对比分析   总被引:5,自引:3,他引:2  
江西相山铀矿田是我国赣杭成矿带西段火山岩系中的热液脉型铀矿田,矿床产于相山火山-侵入杂岩体内部及外侧,在空间上分布不均匀,东南部矿床较少,西北部矿床无论是数量还是品位都明显好于东南部。文章通过相山矿田西北部与东南部地貌形态、花岗斑岩产状、碎斑熔岩物化性质、成矿类型的对比分析,认为这种不均衡的矿床产出规律,不是成矿地质结构差异引起的,而是侵蚀程度不同所致。从矿田西北部到东南部,矿床侵蚀深度逐渐加大。  相似文献   

7.
燕山早期中-酸性岩浆岩侵入于蓟县系铁岭组、青白口系下马岭组地层中.辉钼矿化分布于岩体内部及其围岩中.本文讨论了花岗斑岩和闪长岩体的地质特征、成岩期次、岩石学、岩石化学特征及其含矿性;论述了矽卡岩一斑岩型钼矿床的成矿地质条件、围岩蚀变、矿床特征和矿床成因.  相似文献   

8.
西华山钨矿的花岗岩组成及与成矿的关系   总被引:11,自引:0,他引:11       下载免费PDF全文
西华山钨矿田成矿花岗岩为一复式岩体,该复式岩体由燕山时期第二阶段西华山杂岩体、花岗斑岩单一侵入体组成.与两期三个阶段花岗岩有关,相应具有3次钨的成矿作用,形成了以西华山钨矿为代表的一毓不同规模的钨矿床,成为我国花岗岩区多阶段成岩多次成矿的典型范例.  相似文献   

9.
福建政和夏山铅锌矿是福建省于20世纪50年代发现的大型铅锌矿,其成因类型长期存在分歧。前人多将其归为沉积-改造型铅锌矿床,即矿层在新元古代由含矿热水沉积形成,燕山期岩浆侵入仅对其进行了改造和富集;但也有部分学者认为夏山铅锌矿是受燕山期铜盆庵正长花岗岩侵入作用影响所形成的矽卡岩型铅锌矿床。本文通过对夏山铅锌矿矿区精细的地质调查表明,夏山铅锌矿体的分布及形态与矿区内花岗斑岩密切相关,铜盆庵岩体对夏山铅锌矿的影响表现在后期的叠加、富集作用。为精确厘定夏山铅锌矿成岩成矿时代,文章对夏山铅锌矿矿区内与成矿相关的花岗斑岩进行了精确的锆石La-ICP-MS U-Pb定年工作。测试结果表明矿区花岗斑岩的侵入时代为(173.0±1.7)Ma,要早于铜盆庵岩体(155~150 Ma),而夏山铅锌矿则形成于(173±1.7)Ma(燕山早期)。这一成矿时代与赣东北地区主要的铜、银、铅锌多金属矿的成矿时代较为一致,表明武夷山地区对华南中生代第一期爆发式成矿作用亦有积极响应,具有早燕山期铜、银、铅锌多金属矿的成矿潜力。而结合前人研究成果,将武夷成矿带北段成矿期次划分为173 Ma和90~125 Ma两个重要的成矿期次,这一研究结果对武夷山成矿带进一步开展隐伏、叠加矿床的找矿工作及成矿规律研究具有重要意义。  相似文献   

10.
钨矿和铜矿是江西重要的金属矿产.钨矿床主要与燕山期黑云母花岗岩一二云母花岗岩一白云母花岗岩有密切的时空成生关系(本文称钨列岩体).铜矿床主要与燕山期花岗闪长斑岩-二长花岗斑岩-斜长花岗斑岩有密切的时空成生关系(本文称铜列岩体).这两列成矿岩体虽然都(或主要)是燕山期小型花岗质侵入体,但它们  相似文献   

11.
Pant-y-ffynnon Quarry in South Wales yielded a rich cache of fossils in the early 1950s, including articulated specimens of new species (the small sauropodomorph dinosaur Pantydraco caducus and the crocodylomorph Terrestrisuchus gracilis), but no substantial study of the wider fauna of the Pant-y-ffynnon fissure systems has been published. Here, our overview of existing specimens, a few described but mostly undescribed, as well as freshly processed material, provides a comprehensive picture of the Pant-y-ffynnon palaeo-island of the Late Triassic. This was an island with a relatively impoverished fauna dominated by small clevosaurs (rhynchocephalians), including a new species, Clevosaurus cambrica, described here from a partially articulated specimen and isolated bones. The new species has a dental morphology that is intermediate between the Late Triassic Clevosaurus hudsoni, from Cromhall Quarry to the east, and the younger C. convallis from Pant Quarry to the west, suggesting adaptive radiation of clevosaurs in the palaeo-archipelago. The larger reptiles on the palaeo-island do not exceed 1.5?m in length, including a small carnivorous crocodylomorph, Terrestrisuchus, and a possible example of insular dwarfism in the basal dinosaur Pantydraco.  相似文献   

12.
Lithostratigraphy, physicochemical stratigraphy, biostratigraphy, and geochronology of the 77–70 Ma old series bracketing the Campanian–Maastrichtian boundary have been investigated by 70 experts. For the first time, direct relationships between macro- and microfossils have been established, as well as direct and indirect relationships between chemo-physical and biostratigraphical tools. A combination of criteria for selecting the boundary level, duration estimates, uncertainties on durations and on the location of biohorizons have been considered; new chronostratigraphic units are proposed. The geological site at Tercis is accepted by the Commission on Stratigraphy as the international reference for the stratigraphy of the studied interval. To cite this article: G.S. Odin, C. R. Geoscience 334 (2002) 409–414.  相似文献   

13.
Robert L. Linnen   《Lithos》2005,80(1-4):267-280
The solubilities of columbite, tantalite, wolframite, rutile, zircon and hafnon were determined as a function of the water contents in peralkaline and subaluminous granite melts. All experiments were conducted at 1035 °C and 2 kbar and the water contents of the melts ranged from nominally dry to approximately 6 wt.% H2O. Accessory phase solubilities are not affected by the water content of the peralkaline melt. By contrast, solubilities are affected by the water content of the subaluminous melt, where the solubilities of all the accessory phases examined increase with the water content of the melt, up to 2 wt.% H2O. At higher water contents, solubilities are nearly constant. It can be concluded that water is not an important control of accessory phase solubility, although the water content will affect diffusivities of components in the melt, thus whether or not accessory phases will be present as restite material. The solubility behaviour in the subaluminous and peralkaline melts supports previous spectroscopic studies, which have observed differences in the coordination of high field strength elements in dry vs. wet subaluminous granitic glasses, but not for peralkaline granitic glasses. Lastly, the fact that wolframite solubility increases with increasing water content in the subaluminous melt suggests that tungsten dissolved as a hexavalent species.  相似文献   

14.
15.
Calcite samples were extracted both from the rock matrix and the superficial coating of a karstified fault plane of an underground quarry, located in the eastern border of the Paris basin. The karstification is dated as Quaternary. Analysis of mechanical calcite twinning reveals that only the calcite matrix has also undergone a compression trending WNW that can be attributed to the Mio-Pliocene alpine collision. Both coating and matrix have undergone a strike-slip regime with σ1 roughly trending north–south, that could correspond to the regional present-day state of stress, a strike-slip compression rather trending NNW, modified by local phenomena. To cite this article: M. Rocher et al., C. R. Geoscience 335 (2003).  相似文献   

16.
正20141520 Bo Ying(Key Laboratory of Metallogeny and Mineral Assessment,MLR,Beijing 100037,China);Liu Chenglin Saline Spring Hydrochemical Characteristics and Indicators for Potassium Exploration in Southwestern and Northern Tarim Basin,Xinjiang(Acta Geoscientica Sinica,ISSN1006-3021,CN11-3474/P,34(5),2013,p.594-602,5 illus.,3 tables,28 refs.)  相似文献   

17.
正20141243Chen Ge(Hangzhou Research Institute of Petroleum Geology,PetroChina,Hangzhou 310023,China);Si Chunsong Study on Sedimentary Numerical Simulation Method of Fan Delta Sand Body(Journal of Geology,  相似文献   

18.
正20142599Chen Sanming(Guangxi Key Laboratory of Concealed Deposits Exploration,Guilin University of Technology,Guilin541004,China);He Yuzhou Block Model and Reserves Estimation of Panzhihua Iron Deposit Based on 3D Geological Modeling(Journal of Guilin University of Technology,ISSN1674-9057,CN45-1375/N,33(4),2013,p.610-615,9illus.,1table,15refs.)  相似文献   

19.
正20140594 Bai Daoyuan(Hunan Institute of Geology Survey,Changsha 410016,China);Zhong Xiang Faults in the Jingzhou Basin and Their Tectonic Settings(Geotectonica et Metallogenia,ISSN1001-1552,CN44-1595/P,37(2),2013,p.173-183,6illus.,59refs.)Key words:basin evolution,tectonic setting,South China In the Upper Paleozoic and Jurassic se-  相似文献   

20.
正20141912Cao Hui(State Key Laboratory for Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China)Gravitational Collapse and Folding during Orogenesis:A Comparative Study of FIA Trends and Fold Axial Plane Traces(Geology in China,ISSN1000-3657,CN11-1167/P,40(6),2013,p.1818-1828,9illus.,35refs.,with  相似文献   

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