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1.
初论地幔热柱与成矿——以冀西北金银多金属成矿区为例   总被引:22,自引:8,他引:14  
作者通过对冀两北金、银多金属矿化集中区成矿规律和物探航磁、重力及遥感信息的综合研究,提出冀西北地区存在一个超越内蒙地轴与燕山褶皱带两个不同历史大地构造单元之上的中生代地幔热柱构造。文中例举了地幔热梓构造标志特征,探讨了地幔热柱构造地质作用(超变质作用、岩浆作用、成矿作用)及其时空演化规律,建立了地幔热柱构造的壳幔成矿模式。  相似文献   

2.
试论冀西北金银多金属矿产富集区地幔热柱及其成矿制约   总被引:8,自引:1,他引:7  
本文以冀西北金、银多金属矿产富集区为例,讨论了超越在不同历史大地构造单元之上的中生代地幔热柱构造,论述了地幔热柱构造的地质、地球物理等标志特征,探讨了地幔热柱构造的变质作用、岩浆作用与成矿制约,并初步建立了壳幔成矿体系。  相似文献   

3.
初论胶东地区金矿成矿模式   总被引:6,自引:0,他引:6  
对胶东金矿集中区成矿规律和地球物理信息的综合研究,提出了胶东地区可能存在一个规模较大的中生代地幔热柱-幔枝热构造。从区域构造背景出发,深入讨论了胶东地区的变质作用、岩浆作用、成矿作用的相互关系及其时空规律,初步建立了地幔热柱构造体系的壳-幔成矿模式。  相似文献   

4.
本文通过对冀西北大量金、银多金属矿床的产出时空特征、各种同位素特征、成矿溶液成分及成矿作用等研究认为,冀西北金、银多金属矿产的产出是同一次大的构造-成矿作用形成的,时限为印支-燕山期(以燕山期为主),成矿物质源自地球深部。由于地幔热柱的多级演化将地球深部的成矿物质带到浅部,并由于幔枝构造核部及盖层部位的差异性剥蚀,形成了平面上的“金三角、银镶边”的水平分带和垂向上的上银(铅锌)下金的分带规律。因此,在银铅锌多矿床深部找金是有极大可行性的。  相似文献   

5.
地幔热柱成矿作用研究进展   总被引:15,自引:0,他引:15  
地幔热柱构造是地球内部热传导的基本形式,只是地球的不同演化阶段其表现形式和强度有所不同。研究表明,燕山期强烈的地幔热柱活动沟通了深部成矿物质来源,金、银等元素随地幔热柱多级演化以气态→气—液混合相向上运移,在地幔热柱演化的三级单元——幔枝构造的有利部位聚集成矿。并据幔枝构造的成矿模式提出了华北地区燕山、秦岭、太行、胶辽等主要成矿集中区都是河淮地幔亚热柱控制下的幔枝成矿系列。成矿作用均伴随有强烈的构造—岩浆活动,成矿时代多集中在260~120Ma。金、银多金属矿床具明显的相似性、同源性和深源性  相似文献   

6.
幔枝构造是地幔热柱多级演化的三级单元,其对内生矿产的成矿控矿作用十分明显.文章归纳了幔枝构造的基本特征,并在此基础上将河北省划分成5个幔枝构造区.提出幔枝构造核部、主次拆离带及上置断陷盆地的成矿控矿规律,总结了"内金、外铜-银-铅锌"的成矿格局,以期为本区进一步找矿提供思路.同位素数据统计认为:成矿物质主要源自地球深部,通过地幔热柱多级演化迁移到近地表并逐步就位、成矿.  相似文献   

7.
内蒙古金厂沟梁金矿的构造特征及深部找矿预测   总被引:3,自引:1,他引:2  
燕山运动以来,华北地台北缘进入了典型的陆内伸展造山阶段,究其成因可能与地幔热柱活动密切相关.研究认为金厂沟梁是一较典型的幔枝构造(地幔热柱多级演化的第三级单元),并且是该区主要的成矿控矿构造.本文在简述其成矿构造背景、含金矿脉主要特征的基础上,重点探讨了金厂沟梁金矿的矿体展布、成矿作用、控矿构造,进而总结了成矿规律,归...  相似文献   

8.
初论幔柱构造成矿体系   总被引:12,自引:0,他引:12  
李红阳  侯增谦 《矿床地质》1998,17(3):247-255
从板块构造与板块边界矿床、超大陆旋回与大陆边界矿床、地幔热点与大陆内部矿床的角度 ,阐述了幔柱构造成矿体系的基本思想、分类、成矿特征及旋回性 ,提出了热幔柱和冷幔柱两个成矿体系和地幔热柱 -热点、地幔热柱 -大陆裂谷、地幔热柱 -大洋扩张、冷幔柱 -前寒武纪硅铝壳造山、冷幔柱 -显生宙硅铝壳 /洋壳造山等五个成矿系统 ,并初步划分了矿床成矿系列 ,例举了某些典型矿床。  相似文献   

9.
中国北东部位于西伯利亚板块、中朝板块和西太平洋俯冲消减带所夹持的地域,区内中新生代火山活动十分强烈,火山岩分布广泛,地质演化可分前中生代亚洲域构造演化一板块裂解、拼合的演化阶段和中新生代滨西太平洋构造域演化-地幔热柱作用和伸展构造演化阶段.铀、多金属矿产资源丰富,其成生与中新生代地幔热柱作用有关.  相似文献   

10.
中国北东部及邻区中生代火山岩成因分析   总被引:3,自引:0,他引:3  
运用大陆动力学原理及地幔热柱多级演化观点,通过对中国北东部及邻区中生代火山岩形成的构造环境分析,提出了地幔热柱的多级演化、中下地壳塑性层流及拆离带附近的岩浆房、上地壳的隆陷、区域应力场的变化及深大断裂的沟通是形成中国北东部中生代大规模火山活动的构造机制.  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.
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931.  相似文献   

15.
PALEONTOLOGY     
正20141596 Liu Yunhuan(School of Earth Sciences and Resources,Chang’an University,Xi’an 710054,China);Shao Tiequan Early Cambrian Quadrapyrgites Fossils of Xixiang Boita in Southern Shaanxi Province(Journal of Earth Sciences and Environment,ISSN1672-6561,CN61-1423/P,35(3),2013,p.39-43,3 illus.,20 refs.)  相似文献   

16.
正20141719 Chen Zhijun(State Key Laboratory of Geological Processes and Mineral Resources,China University of Geosciences,Wuhan 430074,China);Chen Jianguo Automated Batch Mapping Solution for Serial Maps:A Case Study of Exploration Geochemistry Maps(Journal of Geology,ISSN1674-3636,CN32-1796/P,37(3),2013,p.456-464,2 illus.,2 tables,10 refs.)  相似文献   

17.
正20140962 Chen Fenning(Xi’an Institute of Geology and Mineral Resources,Xi’an710054,China);Chen Ruiming Late Miocene-Early Pleistocene Ostracoda Fauna of Gyirong Basin,Southern Tibet(Acta Geologica Sinica,ISSN0001-5717,CN11-1951/P,87(6),2013,p.872-886,6illus.,56refs.)  相似文献   

18.
PETROLOGY     
正1.IGNEOUS PETROLOGY20142008Cai Jinhui(Wuhan Center,China Geological Survey,Wuhan 430205,China);Liu Wei Zircon U-Pb Geochronology and Mineralization Significance of Granodiorites from Fuzichong Pb-Zn Deposit,Guangxi,South China(Geology and Mineral Resources of South China,ISSN1007-3701,CN42-1417/P,29(4),2013,p.271-281,7illus.,  相似文献   

19.
正20141205Cheng Weiming(State Key Laboratory of Resources and Environmental Information System,Institute of Geographic Sciences and Natural Resources Research,CAS,Beijing 100101,China);Xia Yao Regional Hazard Assessment of Disaster Environment for Debris Flows:Taking Jundu Mountain,Beijing as an  相似文献   

20.
正20141266Fan Chaoyan(Guangdong Provincial Key Laboratory of Mineral Resources and Geological Processes,Guangzhou 510275,China);Wang Zhenghai On Error Analysis and Correction Method of Measured Strata Section with Wire Projection Method(Journal of  相似文献   

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