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全球奥陶系年代地层学的研究—进展与问题 总被引：6，自引：0，他引：6
综合评述了最近几年全球奥陶系年代地层研究方面的进展与问题。着重讨论了全球奥陶系统一年代地层表中每个统(包括厘定的“阿伦尼克”、“兰维恩—兰得罗”、“卡拉道克”和“阿什极尔”)的范围和可能选择作为划分统和阶的界线标志的生物层或带的位置,指出了当前我国奥陶系年代地层研究中存在的问题。基于全球奥陶系年代地层划分的原则和趋势以及我国广大地质工作者在过去10年中所积累的有关资料,提出了我国及全球奥陶系年代地层的划分方案。 相似文献
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中国第一个“金钉子”剖面的建立 总被引：17，自引：5，他引：12
中国浙江常山黄泥塘发育了穿越中奥陶统达瑞威尔阶底界的连续地层剖面,笔石和牙形刺的连续演化序列使之得以成为全球对比的标准。经国际地层委员会奥陶系分会、国际地层委员会和国际地科联邮投和批准,已成为达瑞威尔阶的全球层型剖面点。 相似文献
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奥陶系研究百余年:从英国标准到国际标准 总被引：4，自引：0，他引：4
英国学者Sedgwick、Murchison和Lapworth等早在19世纪便对奥陶系作出了先驱性的研究,包括创建了奥陶系。但百年来各国主要都集中于地区性的奥陶系研究,并建立了地区性的序列和标准,这在事实上一直都把英国的奥陶系划分作为国际间的对比标准。近三十年来,随着国际奥陶系分会不断推进各国奥陶系的研究工作,并在2007年完成了奥陶系三统七阶的全部全球层型剖面和点位(GSSP)的研究,建立了全球标准。为了便于运用,建议将奥陶系的三统七阶分为20个间隔段,以利于洲际对比,并把地区性的统与阶准确地对比到国际标准上去。同时附上与年代地层划分相一致的奥陶系全球碳同位素的变化曲线。 相似文献
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奥陶系全球界线层型剖面和点位(GSSP)的研究 总被引：8，自引：4，他引：4
简述了奥陶系三统七阶的划分原则和它们的全球界线层型剖面和点位( GSSP)确定或提名经过和问题,并提出了本届国际奥陶系分会移至中国后的主要任务 相似文献
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经联合国教科文组织、国际地科联、国际地层委员会奥陶系分会和志留系分会批准,由中国科学院南京地质古生物研究所主办的"第十届国际奥陶系、第三届国际志留系联合大会"于2007年6月27日上午在南京隆重开幕. 相似文献
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牙形刺是奥陶纪地层划分的主导化石门类,目前已建立了可以全球对比的牙形刺生物化石带,但还缺乏对洲际尺度牙形刺生物带对比资料,特别缺乏精细年代控制的牙形刺生物地层资料。以研究程度较高的亚洲地区为例,梳理了亚洲内部奥陶纪牙形刺生物地层研究资料,初步建立了亚洲地区牙形刺生物地层对比格架,结合国际地质年表研究进展,提出了亚洲地区奥陶纪牙形刺研究需要解决的问题,即以目前执行的IGCP 652项目中国工作组研究任务为依托,开展我国鄂尔多斯西南缘奥陶系多重地层研究,有望获得高精度年代控制的奥陶纪牙形刺生物地层资料。 相似文献
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正1研究目的(Objective)湖北宜昌王家湾是全球上奥陶统赫南特阶底界全球界线层型剖面所在地,也是世界上开展奥陶系和志留系界线对比研究的典型地区,具有很高的地层学研究水平。该地奥陶系五峰组—志留系龙马溪组下部以碳硅泥质页岩发育为特点,沉积连续,化石丰富,具有与中国已经建成的重庆涪陵焦石坝和长宁威远国家级页岩气勘探示范区页岩气勘探主力层系相似的地层和古生物发育特点。区域构造稳定,地层产状平缓,页岩气富集地质条件优越,但志留系页岩气的 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
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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