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1.
胶东招莱地区大-超大型金矿床形成的几个关键因素   总被引:9,自引:0,他引:9       下载免费PDF全文
胶东招莱地区之所以能集中丰富的金矿资源是以下关键地质因素偶合的结果①成矿地质背景是处在新太古代花岗-绿岩地体和后碰撞弧的构造环境下;②控矿断裂经历了多次韧-脆、剪切-拉张的复杂变形过程,形成了宽大的构造岩带,有利于赋存大规模矿体;③控矿断裂是复合-叠加在花岗岩的侵入接触带上,有利于矿液的活动;④根据硫、铅同位素特征及产出地质背景,推断成矿物质主要来自以新太古代绿岩为主的结晶基底;⑤根据氢氧同位素特征,成矿流体为大气水和岩浆水的混合流体,有利于搬运大量成矿物质;⑥矿床与岩脉(特别是煌斑岩脉)有密切的时间和空间关系,表明矿区是构造和岩浆活动的中心,有利于金矿床的形成;⑦成矿时代为燕山晚期.  相似文献   

2.
黑龙江省老柞山金矿成矿模式探讨   总被引:8,自引:0,他引:8  
老柞山金矿经历了早、晚两期成矿地质作用。通过对矿质来源、控矿构造、流体特征、成矿时代等控矿因素的分析 ,确定早期成矿作用为中高温热液蚀变岩型 ,矿体受北西西—东西向张性断裂控制 ,成矿年龄为 (2 39± 34 )Ma,与华力西晚期的岩浆活动有关 ;晚期成矿作用为中温热液充填脉型 ,矿体受北北西—北西向压扭性断裂控制 ,其成因与燕山期的岩浆活动有关。两期成矿作用的成矿物质主要来自于上地幔 ,并有部分壳源物质的加入。  相似文献   

3.
江西大背坞金矿床成因探讨   总被引:2,自引:0,他引:2  
从硫同位素、铅同位素、硅同位素、碳同位素及稀土元素特征等方面资料反映出大背坞金矿成矿物质来源具有双桥山群地层为主、并有燕山期岩浆物质加入的双重特征;从成矿流体包裹体特征分析表明成矿流体主要来源于岩浆水;成矿蚀变矿物的铷—锶同位素获得等时线年龄为118Ma;结合构造演化与构造控矿规律提出了大背坞金矿床成因新认识:即属于受构造控制的中高温岩浆热液矿床。  相似文献   

4.
安徽五河大巩山金矿床地质地球化学特征及矿床成因   总被引:1,自引:1,他引:0  
安徽五河大巩山金矿是受NNE—NS向压扭-张扭性断裂(郯-庐断裂带的次级构造)控制的脉状金矿床。赋矿围岩为新太古界西固堆组变质岩。矿化类型以石英脉型金矿化为主,其次为破碎蚀变岩型金矿化。矿床地质特征、硫、铅、氢、氧同位素地球化学特征、REE元素及成矿流体包裹体地球化学特征表明:成矿物质主要来源于西固堆组变质岩;而成矿流体则以岩浆源为主,并混有部分大气降水的组成。该矿床成因上应属与燕山期花岗质岩浆活动有关的中-高温热液金矿床。  相似文献   

5.
通过对小秦岭金矿成矿地质条件及成矿物质来源的讨论 ,认为区域变质、混合 (花岗 )岩化等促使基底岩系中金被多次活化析出 ,在变质核杂岩持续隆升背景下 ,成矿流体向控矿剪切带运移沉淀 ,燕山期构造—岩浆活动为金矿富集定位创造了热—构造环境。提出金矿分布与变质核杂岩构造具有对应性 ,本区金矿化具垂向构造分带性。  相似文献   

6.
江西大背坞金矿成因探讨   总被引:1,自引:0,他引:1  
从硫同位素、铜同位素、硅同位素、碳同位素及稀土元素特征等方面资料反映出大背坞金 成矿物质来源具有双桥山群地层为主,并有燕山期岩浆物质加入的双重特征;从成矿流体包裹体特征分析成矿流体主要来源于岩浆水;成矿蚀变矿物的铷-锶同位互获得等时线年龄为118Ma;结合构造演化与构造控矿规律提出了大背坞金矿床因新认识,即属于受构造控制的中高湿岩浆热液矿床。  相似文献   

7.
河南祁雨沟金矿床地质地球化学特征和矿床成因讨论   总被引:3,自引:0,他引:3  
本文介绍了祁寸沟金矿床的成矿地质背景和矿床地质地球化学特征,讨论了矿床成因,通过含矿角砾岩体特征,矿物学、硫、铅、氢、氧同位素地质学和流体包裹体的研究,确定成矿物质主要来自下伏太古宇太华群;气液爆破角砾岩体为容矿构造,成矿作用是在中生代岩浆活动期后气液爆破-沸腾作用下完成的,成矿流体以岩浆水为主,混入部分大气水;矿床成因属岩浆热液矿床。  相似文献   

8.
在详细论述桂东地区金矿床赋存的构造地质环境,控矿地层岩性及岩浆活动与金矿化与关系等成矿地质特征基础上,通过矿石微量元素和稀土元素特征及硫,铅,氢氧稳定同位素组成特征研究证实,在矿物质以深源岩交为主,混有少量壳源物质成矿流体为岩浆水,后期混有少量变持水和大气降水,矿床具有多源,多成因及多期次成矿特征,矿床成因类型主要有岩浆热液,变质热液和复合叠加类型,而以后者为主。  相似文献   

9.
水晶屯金矿床稳定同位素地球化学研究   总被引:1,自引:0,他引:1  
通过对水晶屯金矿床与区域上典型金矿床的硫、铅、氢、氧等稳定同位素的对比研究,阐明本区金矿成矿物质主要来源于太古宇崇礼杂岩,太古宙区域变质作用仅形成金的初步富集,印支-燕山早期的构造岩浆活动促成石英脉主体形成,燕山期继承性构造岩浆活动对先成脉体的叠加改造作用是成矿的重要因素,成矿流体来源于岩浆水.本矿床为具有层控性质的岩浆热液型矿床.  相似文献   

10.
金水铜矿床受构造控制,热液成矿标志明显。依据成矿地质背景及矿床地质特征、硫同位素和流体包裹体特征等研究认为,成矿物质来源深部,成矿作用具多阶段,成矿流体具热卤水性质;矿床初步确定为岩浆期后热液脉型铜矿床。  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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