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依托青海省矿产地质志研编项目,在收集矿产勘查、科研成果资料以及调研典型矿床的基础上,对青海省铁矿时空分布、成矿系列和成矿模式进行了研究,取得以下主要成果:1)青海省铁矿床主要形成于元古代、寒武纪—奥陶纪和三叠纪,自北向南成矿时代由老变新,空间上主要分布于祁连、东昆仑构造带,祁连构造带以产出寒武纪—奥陶纪海相火山-沉积型铁矿床为特色,东昆仑构造带主要产出元古代沉积变质型和三叠纪接触交代矽卡岩型铁矿床;2)将青海省铁矿床划分为九个矿床成矿系列;3)厘定了青海省主要类型铁矿床产出的构造环境,认为元古代沉积变质型铁矿产于大陆边缘,寒武纪—奥陶纪及二叠纪—三叠纪海相火山-沉积型铁矿产于大陆裂谷、岛弧或弧后盆地,三叠纪接触交代矽卡岩型铁矿产于碰撞-后碰撞造山带;4)概述了九个系列矿床成矿特征,建立了元古代沉积变质型、寒武纪—奥陶纪海相火山-沉积型、二叠纪—三叠纪海相火山-沉积型、三叠纪接触交代矽卡岩型4个主要矿床成矿系列的成矿模式。 相似文献
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华北地区镍矿床(点)主要分布在内蒙古、河北省及河南省等地,已发现镍矿床(点)19处,其中大型矿床1处,中型矿床3处,小型矿床8处,矿点7处。新元古代和晚古生代是华北地区镍矿床形成的2个高峰期。矿床类型以岩浆型为主,其次为风化壳型和沉积变质型。沉积变质型镍矿床主要产在华北陆块区内,形成环境与裂陷盆地有关;岩浆型和风化壳型镍矿床主要产在克拉通边缘或造山带,形成环境与大陆边缘裂解或后碰撞伸展环境有关。分析认为,华北陆块北缘出露的镁铁质超镁铁质岩、二连贺根山地区蛇绿混杂岩及内蒙古南端秦祁昆造山带寒武系黑色岩系地层,均具有较好的镍矿资源找矿潜力。 相似文献
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超大型岩浆硫化物矿床的类型及地质对比意义 总被引：3，自引：0，他引：3
按照镍储量≥50万吨、矿石品位Ni≥1％,若Ni≥1％,共生元素铜或铂族元素达到经济利用品位,这三条标准,确定全球有十个超大型岩浆硫化物矿床。它们分属五种类型:①元古代与古陨石坑有关的苏长岩—辉长岩型矿床;②元古代与大陆边缘断裂有关的二辉橄榄岩型矿床;③显生宙与大陆裂谷有关相当溢流玄武岩的侵入体矿床;④太古带绿岩带与柯马提岩浆有关的矿床;⑤早元古代大陆层状大型侵入杂岩体中硫化物与铂族矿床。通过矿床地质对比认为金川矿带、康滇裂谷带、喀拉通克带是有利找到此类新矿床的地区。 相似文献
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俞 《四川地质科技情报》1994,(2):42-42
昆明工学院冉粜英等撰文提出，随着地壳演化，康滇地轴南段发生过多旋回裂谷-裂陷槽演化，即古元古代-中元古代金沙江陆缘海型裂陷槽、中元古代东川一易门陆间裂陷槽、澄江后造山裂谷和T3-E1康滇大陆裂谷，并在其中分别产出大红山-拉拉式火山沉积变质／热水沉积铜铁矿床、 相似文献
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辽东裂谷为古元古代拉伸环境下产生的EW向陆内裂谷,裂谷的北缘斜坡带赋存有大石桥—塔子岭超大型菱镁矿带,中央裂陷带赋存了瓦峪—青城子大型菱镁矿带。菱镁矿床的产出与成矿物质来源的位置有较大的关系,同时与沉积的环境因素、后期的各种扰动因素有关。在古元古代富含CO_2的环境中,源于太古宙地块剥蚀物中和远源火山喷发物中的镁质进入海水,在持续稳定的陆缘潮间-潟湖蒸发环境中,在藻类生物吸附吸附作用的有力辅助下,沉积了巨厚的富镁碳酸盐岩,经过成岩作用形成原生菱镁矿层。在区域变质-变形过程中,原生菱镁矿层经过褶皱变形和矿物重结晶,完成形态方面的最终定型;因此,辽东裂谷菱镁矿属于沉积-变质型矿床。 相似文献
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研究区内的中元古代魏家沟岩群原岩为一套碳酸盐岩、陆缘碎屑岩及火山岩建造,形成于大陆裂谷-活动大陆边缘阶段,并于1036 Ma左右遭受变质变形.通过岩浆岩形成构造环境的判别,研究区中元古代岩浆活动贯穿于板块碰撞前、同碰撞及碰撞后.伴随着造山带的演化,本区中元古代经历了3期韧性变形,分别形成于大陆裂谷、活动大陆边缘及碰撞造山阶段.通过上述研究,确定了本区中元古代造山带的存在,并经历了大陆裂谷-被动大陆边缘-活动大陆边缘-碰撞造山的地质演化过程,证实了格林维尔造山运动在华北板块北缘的存在和对中元古代末期Rodinia超大陆拼合的响应. 相似文献
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古元古代-中国重要的成矿期 总被引：7，自引：1，他引：6
古元古代是中国十分重要的成矿期,矿种多、成矿规模大、矿床类型复杂。与太古宙相比,古元古代构造体制发生了本质的变化,由太古宙全活动体制转换为活动带和稳定地块并存的构造格局,因而其成矿特征与太古宙有明显差别。太古宙成矿主要与绿岩带有关,相应形成铁、金、铜锌等矿床。在古元古代,与成矿有关的构造环境主要是与拉伸、裂陷和伸展活动有关的裂谷环境,其次为活动大陆边缘裂谷及弧后盆地和被动大陆边缘盆地,有少部分与伸展构造有关,产在深大断裂带中的矿床。因而古元古代成矿是以裂谷、裂陷为主的成矿体系。在古元古代形成华北陆块北缘东段辽吉与古元古代裂谷作用有关的硼、铁、菱镁矿、滑石、铅锌、铜镍、岫玉等矿床成矿系列、华北陆块南缘中条山-王屋山与古元古代裂谷作用有关的铜矿床成矿系列、佳木斯微陆块与古元古代沉积变质作用有关的石墨、金矿床成矿系列等11个主要矿床成矿系列。相应大规模成矿的有铁、铜、金、铅锌、金红石、钛铁矿等金属矿床及石墨、菱镁矿、硼、滑石等非金属矿床。就是同一种矿产,与太古宙相比,矿床类型也有明显差别,如条带状铁建造(BIF)型铁矿,在太古宙为阿尔戈马型,而古元古代则以苏必利尔湖型为主。 相似文献
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Emily Keeble David I. Whiteside Michael J. Benton 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(2):99-119
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
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Gilles Serge Odin 《Comptes Rendus Geoscience》2002,334(6):409-414
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.
The effect of water on accessory phase solubility in subaluminous and peralkaline granitic melts 总被引：4，自引：0，他引：4
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
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Muriel Rocher Stéphane Baize Stéphane Jaillet Edward Marc Cushing Yannick Lozac&#x;h Francis Lemeille 《Comptes Rendus Geoscience》2003,335(8):701-708
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
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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
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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
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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
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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
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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