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1.
西南三江构造带及扬子西缘在前寒纪时期，或者说元古宙时期，只有两个在形式上有联系的构造区，它们的基底岩群和构造演化都不尽相同。当时的欧亚大陆虽大致在现今位置，而冈瓦纳大陆尚在赤道附近，并且是“内部分隔”的微大陆。因而，地理上的“西南三江”当时明显地分割为东、西两部份；现代则划分为三部份，其中应突出北羌塘－澜沧江及拉竹龙－金沙江－藤条江两构造带之间的唐古拉－昌都－兰坪－思茅过渡带或转换（化）带的存在事实。 相似文献
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滇中地区昆阳群中的刺穿构造 总被引：2，自引：2，他引：0
滇中中元古界昆阳群地层中出现大小不等的２００多个刺穿构造,它们由脆性变形和塑性变形两部分或其一部分组成。由两条不同性质断裂挟持的（下盘为逆断裂,上盘为正断裂）老地层组成的构造岩片,斜冲于新地层之中,形成刺穿构造。它们是区域内逆冲推覆断裂同期及后期活动产物,其脆性变形部分是逆冲推覆断裂及派生次级逆冲推覆断裂的特殊前峰,即楔形前峰;而塑性部分是逆冲推覆断裂形成过程中,由岩石破碎－受拉张、垮塌－受压应力、地下水参与下塑变,并沿断裂流变侵位固结的产物,称之为因民角砾岩。刺穿构造组构复杂,可分成复式向斜型、复式背斜型、叠瓦型、半边背斜型及因民角砾岩型等。区域上刺穿构造组合成单冲式和双冲式。刺穿构造内铜矿体为改造富集型的脉状铜矿体,形态复杂多为盲矿体。它们受刺穿构造内与边界断裂平行的断裂系和有利地层（因民组三段、落雪组一、二段）、岩性（不纯白云岩）双重控制。此类型矿床在云南铜矿中占有较大比例,有大型矿床１个、中型４个、小型２７个及众多矿点。探明储量超过１３０万吨,且都为富矿。 相似文献
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根据华北陆台北缘金矿的赋存部位和富集特点，划分出9种金矿类型。金矿的形成主要受韧性剪切带控制，多形成于韧脆性剪切带的上部；金的迁移和富集经历3个阶段：（1）地体表壳岩矿源层形成阶段；（2）地体拼贴期韧性剪切带形成阶段；（3）中生代、部分古生代岩浆－构造带形成阶段。控制金矿分布的是古生代近EW向和燕山期NE向构造带，主要为继承早期地体拼贴边界的长寿断裂。金矿集中区位于长寿断裂的交汇部位。 相似文献
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吉林省安图县海沟金矿床控矿构造特征 总被引：2，自引：0，他引：2
海沟金矿是大型石英贫硫化物脉型金矿床。矿区侵入岩可划分为四个花岗岩单元，矿体（脉）在平、剖面上都具有斜列的特点。含金石英脉的产出和分布严格受ＮＮＥ－ＮＥ向断裂控制。金矿区控矿构造型式为ＥＷ向大断裂的派生断裂控制矿床，成矿构造序列划分为成矿前、成矿期、成矿后构造。构造对矿床（矿体）的控制作用主要表现为等距性构造控制矿脉分布；断裂多期活动对富矿体的控制。分析了断裂构造地球化学特征，表明成矿作用是以充填 相似文献
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渤海湾盆地南堡凹陷断裂系统成因的构造解析 总被引：2，自引：0，他引：2
本文在对南堡凹陷三维联片地震资料构造解析的基础上,应用先存构造构造条件下的断层作用模式,结合构造物理模拟实验成果,系统分析了南堡凹陷的断裂系统和构造样式。表明,南堡凹陷是典型的斜向伸展构造样式,其中受铲式和（或）坡坪式边界正断层及先存断裂共同控制的复式 “y” 形样式是南堡凹陷基本的构造样式,其次是复式“x”形、“多米诺式”、“阶梯式”和“铲式扇”断块构造样式。平面上划分出为4个断裂系统：北堡－老爷庙断裂系统,高柳断裂系统,柏各庄断裂系统和南堡断裂系统,其中高柳断裂系统和南堡断裂系统进一步分别划分为2个和3个子断裂系统;纵向上划分出下部（E2s3构造层）和上部（E2s1-Q地层）两个断裂系统,E2s2是上下两个断裂系统的过渡层,断层不发育。断层的平面组合形式有4种,分别为：平行状、平行交织状、“梳状”和“帚状”。“两期伸展” 的变形叠加模式可以合理地解释南堡凹陷新生代的构造变形：E2s3期的构造变形在是以中生代形成的先存构造为基础,北西-南东方向伸展作用的结果;E2s1以来的变形是以E2s3期形成的断裂为先存构造,南北向伸展作用的结果;E2s2是应力体制转换的过渡阶段。凹陷边界断层（西南庄断层、柏各庄断层和高柳断层）存在显著的分段性,不同段落断层的走向、性质和活动性、均表现出很大的差异,而且在不同构造演化阶段发生显著的变化。凹陷边界断层及凹陷内的南堡断层、和蛤坨断层组成的构造格架对南堡凹陷断裂系统的形成和演化起重要的控制作用,复杂的先存构造是造成断裂系统横向差异的根本原因。 相似文献
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广南木利锑矿床为—产于下泥盆统坡脚组中段硅质岩中的热水沉积一改造富集而成的层控矿床。受下列因素控制：①大陆边缘裂谷带中由深大断裂（那外－西洋江断裂和富宁断裂）控制的断陷槽为热水沉积作用提供了古构造和古地理条件；②坡脚组中段的热水沉积硅质岩富含锑，是成矿的物质基础，并在局部由沉积。成岩作用成矿；③背斜构造为主要控矿构造，矿体主要产于背斜核部虚脱空间；④硅化与矿化关系密切，强硅化作用有利于富矿体的形成。 相似文献
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建阳水吉矿区风山林层控银铅锌矿成矿机制及演化模式 总被引：4，自引：0，他引：4
本文初步分析研究了省内建阳水吉矿区凤山林层控银锌矿的成矿机制及演化过程，总结了这一组水沉积变质－岩浆气液叠加改造再造型层控矿床组合成因模式；在大陆雏形裂谷构造环境下经热水沉积形成银铅锌（硫）矿源层－上元古界龙北溪级中上段（Pt3l^2 3)母含矿建造，深源名模式年龄为946－814百万年；经区域变质期间“多”字型塑性流动褶皱作用，矿质二次迁移富集形成矿石铅模式年龄为695－483百万年的含矿层（A）型；具“走滑转换构造”性质的燕山期控矿“S”形断裂构造，是导生含矿中基性脉岩（浆）热源体－生矿建造和决定矿质再次叠加改造成矿（B型）及再造成矿（C型）的关键。从中提出了“三造一体”的成矿富集机制。 相似文献
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黔西南右江区金矿床控矿构造样式及成矿作用分析 总被引：4，自引：4，他引：4
对黔西南烂泥沟，丫他，百地等几个金矿床控矿断裂构造的观察研究发现，它们同处于应变椭球体的长轴方位，其与同级褶皱，横张断裂、“Ｘ”剪切断裂系同一构造应力场作用之产物。因而具有相似的构造组合样式，但又不同程度地受到后期构造的改造或叠加。种种迹象表明，控矿构造的多期活动性，成矿作用的叠加性，以及构造－成矿作用的同时性，是这些矿床的共同特征。 相似文献
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吉林东部二叠纪和三叠纪生物沉积和构造古地理格局 总被引：2，自引：0，他引：2
吉林省东部地区以图们江构造带为界，其东西两区在生物地层、沉积建造和构造样式等诸方面存在显著的差异。其中石炭、二叠系的差异最为明显，三叠系的差异性明显变小。延边西部及吉林中部地区属于吉中地体，而延边东部地区则属于珲春地体，两者拼合的时间为Ｔ（１－２），图们江构造带是主拼合带。 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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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20141756 Chen Ruige(Mathematical College,China University of Geosciences,Beijing100083,China);Zhou Xun Numerical Simulation of Groundwater Level Fluctuation in a Coastal Confined Aquifer with Sloping Initial Groundwater Level Induced by the Tide(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(7),2013,p.1099-1104,6 illus.,16 refs.) Key words:confined water,groundwater level 相似文献
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正20141408 Cai Jia(Institute of Geology,Chinese Academy of Geological Sciences,Beijing100037,China);Liu Fulai Petrogenesis and Metamorphic P-T Conditions of Garnet-Spinel-Biotitebearing Paragneiss in Danangou Area,Daqingshan-Wulashan Metamorphic Complex Belt(Acta Petrologica Sinica,ISSN1000-0569,CN11-1922/P,29(7), 相似文献
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正20142386An Guoying(China Aero Geophysical Survey and Remote Sensing Center for Land and Resources,Beijing 100083,China)Application of Satellite Remote Sensing in Regional Hydrogeological Investigation:Taking Cenozoic Strata in Wenquan Sheet(1∶250 000)of Karakoram Range as an Example(Geosci- 相似文献
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正20141016An Chengbang(Key Laboratory of Western China’s Environmental Systems,Ministry of Education,Lanzhou University,Lanzhou 730000,China);Zhao Yongtao Lake Records during the Last Glacial Maximum from Xinjiang,NW China and Their Climatic Impli- 相似文献
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正20141538 Cao Qing(School of Earth Sciences and Engineering,Xi’an Petroleum University,Xi’an 710065,China);Zhao Jingzhou Characteristics and Significance of Fluid Inclusions from Majiagou Formation,Yichuan Huangling Area,Ordos Basin(Advances in Earth Science,ISSN1001-8166,CN62-1091/P,28(7),2013,p.819-828,7 illus.,3 tables,43 refs.) 相似文献
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正20142002 Wei Hualing(Institute of Geophysical and Geochemical Exploration,Chinese Academy of Geological Sciences,Langfang065000,China);Zhou Guohua Element Content and Mineral Compositions in Different Sizes of Soil in Tongling Area,Anhui Province(Geological Bulletin of China,ISSN1671-2552,CN11-4648/P,32(11),2013,p.1861 相似文献