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氟碳钙铈矿结构中晶体缺陷的高分辨电镜研究 总被引:1,自引:1,他引:1
用高分辨电子显微术(HREM)研究了氟碳钙铈矿(BS)晶体结构中的无序堆垛和体衍交生现象,结果表明该矿物的衍生多晶体是由钙-铈氟碳酸盐矿物中不同组分的氟碳铈矿(B)和直氟碳钙铈矿(S)结构单元层沿c方向无序堆垛而成。高分辨结构象揭示出氟碳钙铈矿衍生多晶体的微结构特征。讨论了氟碳钙铈矿结构中的堆垛层错等晶体缺陷现象。 相似文献
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王立本 《矿物岩石地球化学通报》1992,(1)
钙-稀土氟碳酸盐矿物属六方球霞石(Vaterite)型碳酸盐。已命名的有四种矿物,即Bastnacsitc,Parisite,Roentgenite和Synchysite。由新矿物及矿物命名委员会审订的汉译名分别为:氟碳铈矿,氟碳钙铈矿,伦琴石和直氟碳钙铈矿。与此相关的还有Bastnaesite-(Y),Synchysite-(Y),Synchysite-(Nd)等变种矿物分别译为氟碳钇矿、直氟碳钙钇矿和直氟碳钙钕矿。这些汉译名显然是遵循几个不同的原则确定的, 相似文献
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根据HRTEM研究,在四川西昌地区的钙稀土氟碳酸盐矿物衍生多晶体中发现了四种不同的B10S8型[即氟碳怖矿(B)/直氟碳钙铈矿(S)为10:8]新规则混层矿物(B10S8-I,B10S8-Ⅱ,B10S8-Ⅱ和B10S8-Ⅳ)。用SAED和HREM方法确定了四种新规则混层矿物的晶体结构对称性、晶胞参数、结构堆垛模式及晶体化学式等。四种B10S8新规则混层矿物结构中,Ce-F离子层的堆垛层序以及两个Ce-F离子层之间的碳酸根离子层的排列方式均不同。同时还观察到该类矿物中的畸结构及堆垛层错等。 相似文献
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钙稀土氟碳酸盐矿物中新多型体的HREM研究 总被引:1,自引:0,他引:1
利用高分辨电子显微术(HREM)研究了钙稀土氟碳酸盐矿物系列中氟碳铈矿(B)/直氟碳钙铈矿(S)的混层结构。发现并确定了B_5S_2(IH,3R)、B_5S_4(3R,6R)和B_(18)S_(10)(IH)规则混层矿物中5种新多型的晶体结构类型、晶胞参数以及理论晶体化学式等。HREM研究揭示出,在B_mS_n(m>n)型规则混层矿物新多型体的结晶过程中,成矿地质环境是复杂的。阐明了这些多型体是由该系列矿物中的氟碳铈矿(B)和直氟碳钙铈矿(S)结构单元层以不同比例沿c轴方向的有序堆垛构成。 相似文献
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四川冕西霓石碱性花岗岩中的稀土矿物主要为钙稀土氟碳酸盐矿物系列,通过选区电子衍射(SAED)和高分辨透射电子显微术(HRTEM)研究发现该系列矿物晶体结构中广泛发育复杂多样的微观地质异常现象,其主要类型有:(1)由该系列两个端员矿物氟碳铈矿结构层(B)与直氟碳钙铈矿结构层(S)以不同比例沿C轴方向有序堆垛形成的BmSn型规则混层结构;(2)无序堆垛形成的有序一无序结构晶畴;(3)由堆垛层错形成的无序混层结构,氟碳钙铈矿中不同多型体间的共格连生结构和相转变等;(4)氟碳铈矿结构中的平行于[001]方向的平移畴及一维无公度调制结构,该类调制结构可能是由于矿物中原子占位有序度的变化而形成的无序结构状态。 相似文献
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四川省牦牛坪稀土矿区钙稀土氟碳酸盐矿物有氟碳铈矿、氟碳铈矿以及笔者发现并命名的牦牛矿。本文旨在简述氟碳铈和氟碳钙铈矿的矿物学特征。牦牛坪钙稀土氟酸盐类矿物具有强选择轻稀土的特点。 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 Lozach 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