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中国科学院地质与地球物理研究所2006学术年会

作者： G li~(1,2,3),B.Ning1,W.Wan~1,and B.Zhao~(1,2,3) 1 institute of geology and geophysics,chinese academy of sciences,beijing,China 2 Wuhan institute of Physics and Mathematics,CAS,Wuhan,China 3 Graduate School of chinese academy of sciences,beijing,China

During the two geomagnetic storms which occurred on 1 October 2002 and 22 January 2004,the strong ionospheric scintillations of the GPS L1 band were observed atWuhan station (30.6,114.4,45.8ip),which is situated near the northern crest of the equatorial ionosphere *** found that the intense scintillations were associated with the main phases of the storms and were co.located with the enhancement of the equatorial ionization anomaly (EIA);the co.existence of large- and small-scale irregularities at post-midnight was also found. The results may be relevant regarding the influence of the equatorial ionospheric eastward electric field during geomagnetic *** the other hand,GPS L1 band scintillations were not observed during the other two similar storms on 16 july 2003 and 20 November *** of the reasons is probably that the sporadic E layer observed at the storms inhibited the generation of spread F by changing the Pedersen co.ductivity and suppressing the upward plasma drift.

关键词： Ionosphere(Ionospheric irregularities Midlatitude ionosphere) - Magnetospheric physics(Storms and substorms)

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Terrestrial mollusc reco.ds from Xifeng and Luochuan L9 loess strata and their implications for paleoclimatic evolution in the chinese Loess Plateau during marine Oxygen Isotope Stages 24-22

Terrestrial mollusc records from Xifeng and Luochuan L9 loes...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： B.Wu~(1,2) and N.Q.Wu~1 1 Key Laboratory of Cenozoic geology and Environment,institute of geology and geophysics,chinese academy of sciences,P.O.Box 9825,beijing,10002.,China 2 Graduate university of the chinese academy of sciences,beijing,100049,China

Marine Isotope Stages 24-22 is a key period of the Mid-Pleistocene Transition,however,its climate variability is still *** co.rse-grained loess unit L9,one of the most prominent units in the chinese loess stratigraphy,yields a high potential terrestrial reco.d of paleoclimatic and paleoenvironmental changes during this *** this study, two high-resolution terrestrial mollusc reco.ds of L9 loess strata from the Xifeng and Luochuan sequences in the chinese Loess Plateau were *** mollusc results show that the MIS 24,the early and late parts of MIS 22 were dominated by co.d and dry *** mild-humid climate occurred in MIS 23 and the middle part of MIS *** climatic co.ditions at Xifeng region were co.ler and more unstable co.pared to Luochuan region.A co.parison of mollusc species co.position and other proxies of L9 strata (MIS 24-22) with those of li loess units(MIS 4-2) indicates that the L9 loess was not deposited under the most severe glacial co.ditions in Quaternary climate history as suggested in previous *** study shows that climatic co.ditions in the Loess Plateau during the L9 loess forming period were similar to that of gentle glacials(MIS 24 and MIS 22) and interglacial(MIS 23),as suggested by the marineδO *** co.ling fluctuations occurred at 30 ka, 900 ka and 880 ka,which might hint to the global "900 ka co.ling event".The "900-ka event" in the Loess Plateau does not seem to be a simple long glaciation,but rather several co.plex climatic fluctuations superposed on a general co.ling *** uplift of the Tibetan Plateau and the general co.ling experienced by the Earth during this period may have resulted in abundant dust sources and increased dust transport capability,as indicated by increased grain size and the mass accumulation rate of L9 loess.

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Magnetostratigraphic study of Cretaceous depositional succession in the northern Kuqa Depression,Northwest China

Magnetostratigraphic study of Cretaceous depositional succes...

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中国科学院地质与地球物理研究所2006学术年会

作者： PENG Shoutao~1,li Zhong~1,HUANG Baochun~2,liU Tao~3 & WANG Qingchen~1 1.State Key Laboratory of lithospheric Evolution,institute of geology and geophysics,chinese academy of sciences,beijing 10002.,China 2.Division of the Earth’s Deep Structure and Process,institute of geology and geophysics,chinese academy of sciences,beijing 10002.,China 3.beijing institute of geology for Mineral Resources,beijing 100012,China

There are some quite different disputes about chronostratigraphic division of the Cretaceous in the Kuqa Depression,northern margin of the Tarim *** then carried on a magnetostratigraphic study on Cretaceous succession in the Kuqa River and Kezilenuer Channel *** paleomagnetic analyses on 446 specimens from 265 sites permit a co.struction of a preliminary magnetic polarity sequence for the Cretaceous *** with paleobiologic co.straints from calcareous nannofossils,magnetostratigraphic results show that the Bashenjiqike Formation was probably deposited during the late Campanian to Maastrichtian stages of the Late Cretaceous,ranging from about 79.1 to 65 6 *** the other hand,magnetozones identified from the Yageliemu,Shushanhe,and Baxigai formations may principally co.relate with chrons M18r to M3 of the Geomagnetic Polarity Time Scale(GPTS).This co.relation suggests that these three formations were very likely to be formed during the early-middle stage of the Early Cretaceous between the Berriasian to the early Berremian stages(141.9-124.1 Ma).Therefore it is possible that the Bashenjiqike Formation co.tacts the underlying strata with an unco.formity and there is a giant sedimentary hiatus during the period of the late Barremian to early Maastrichtian stages in the Kuqa Depression.

关键词： Kuqa Depression Cretaceous magnetostratigraphy

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Precambrian key tectonic events and evolution of the North China craton

Precambrian key tectonic events and evolution of the North C...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： MINGGUO ZHAI~(1,2),TIE-SHENG li~(1,2),PENG PENG~(1,2),BO HU~(1,2),FU liU~(1,2) & YANBIN ZHANG~(1,2) 1 State Key Laboratory of litho spheric Evolution,institute of geology and geophysics, chinese academy of sciences,PO Box 9825,beijing,10002.,China 2 Key Laboratory of Mineral Resources,institute of geology and geophysics, chinese academy of sciences,PO Box 9825,beijing,10002.,China

The North China craton(NCC)is one of oldest cratons in the world,with crust up to c.3.8 Ga old,and has a co.plicated *** main Early Precambrian geological events and key tectonic issues are as follows.(1)Old co.tinental nuclei have been reco.nized in the NCC,and the oldest remnants of granitic gneiss and supracrustal rocks are 3.8 Ga *** main crustal growth in the NCC took place at 2.9-2.7 *** NCC can be divided into several microblocks,which are separated by Archaean greenstone belts that represent co.tinental accretion surrounding the old co.tinental nuclei.(2)By 2.5 Ga,the microblocks amalgamated to form a co.erent craton by co.tinent-co.tinent,arc-co.tinent or arc-arc *** tectonic processes in Neoarchaean and modern times appear to differ more in degree than in principle. Extensive intrusion of K-granite sills and mafic dykes and regional upper amphibolite-to granulite -facies metamorphism occurred,and marked the beginning of cratonization in the NCC. co.val ultramafic-mafic and syenitic dykes of c.2500 Ma in Eastern Hebei indicate that the NCC became a stable,thick and huge co.tinent at the end of the Archaean,and probably was a part of the Neoarchaean superco.tinent that has been suggested by previous studies.(3)In the period between 2500 and 2350 Ma,the NCC was tectonically inactive,but the development of a Palaeoproterozoic volcanic and granitic rocks occurred between 2300 and 1950 *** volcanic -sedimentary rocks are termed Palaeoproterozoic mobile belts;these have a linear distribution, and were affected by strong folding and metamorphism at 1900-1850 Ma,and intruded by granites and pegmatites at 1850-1800 *** Palaeoproterozoic mobile belts formed and evolved within the craton or co.tinental margin(epico.tinental geosyncline).Some 2.30-1.95 Ga rift-margin, passive co.tinental margin deposits,analogous arc or back-arc assemblages,as well as HP and HT-UHT metamorphic co.plexes seem to be co.parable with many in the late Phane

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IN-SITU TESTS AND A STOCHASTIC STRUCTURAL MODEL OF ROCK AND SOIL AGGREGATE IN THE THREE GORGES RESERVOIR AREA,CHINA

IN-SITU TESTS AND A STOCHASTIC STRUCTURAL MODEL OF ROCK AND ...

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中国科学院地质与地球物理研究所2004学术年会

作者： X.li~1,Q.L.liao~1,J.M.He~2 1) institute of geology and geophysics,chinese academy of sciences 2) China university of Mining and technology

Rock and soil aggregate(RSA) co.posed of soil and rock blocks is a special geologic material. The study of the mechanical behaviour of RSA is of great importance in designing rock slope for *** this paper,in-situ direct shear tests on three samples of RSA in the Three Gorges reservoir area were carried out to examine its mechanical *** was shown that the mechanical properties of RSA were close related to rock percentage and predominated by the staggered structure of the rock blocks. Acco.ding to the geometrical features of rock blocks inside the RSA obtained by geological investigation and statistics,a stochastic structural model of RSA was put forward by means of Monte-Carlo *** the mechanical response of the RSA was numerically simulated using *** co.parsion,the numerical results co.ncided with the test *** is suggested that the numerical simulation procedure proposed in this paper is an effective approach to study the co.plex mechanical behaviour of RSA.

关键词： rock and soil aggregate(RSA) in-situ test stochastic structural model Monte-Carlo method numerical modelling and the Three Gorges

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试论“盆”“山”耦合和脱耦研究的方法学

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石油与天然气地质 2004年第3期25卷 239-246页

作者：吴根耀马力中国科学院地质与地球物理研究所北京100029 中国石化江苏油田江苏扬州225009

“盆”“山”耦合和脱耦把造山作用和盆地发育当作一个整体来研究其统一的运动学过程和动力学机制 ,必须有相应的方法论作保证。针对这一问题 ,有 3个方面需要讨论 :1)空间关系上 ,要在确定一个时间段的基础上正确划分“盆”“山”系统 ... 详细信息

“盆”“山”耦合和脱耦把造山作用和盆地发育当作一个整体来研究其统一的运动学过程和动力学机制 ,必须有相应的方法论作保证。针对这一问题 ,有 3个方面需要讨论 :1)空间关系上 ,要在确定一个时间段的基础上正确划分“盆”“山”系统 ;2 )两套分类体系并用 ,在“正序”的研究和区域的研究中采用理性的系统分类 ,在“反序”的和局部 (主要指油气藏 )的研究中以应用性的分类为主 ;3)以造山带和盆地研究近年里形成的成功方法为基础 ,努力汲取各种新知识 ,将思路、方法和技术手段三者有机地结合起来。“盆”“山”耦合和脱耦研究自身 ,包括其方法学 ,不断开拓新领域 ,将可能成为中国大陆油气勘探新的理论指导。

关键词：方法学 “盆”“山”耦合和脱耦 “盆”“山”系统分类体系薪技术手段

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Rb-Sr and Sm-Nd isotopic systematics of the lherzolitic shergottite GRV 99027

Rb-Sr and Sm-Nd isotopic systematics of the lherzolitic sher...

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中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： Tao liU~(1,2,3),Chaofeng li~(1,3),and Yangting liN~(1*) 1 Key Laboratory of the Earth’s Deep Interior,institute of geology and geophysics,chinese academy of sciences, beijing 10002.,China 2 Guangzhou institute of Geochemistry,chinese academy of sciences,Guangzhou 510640,China 3 Graduate School of chinese academy of sciences,beijing 100039,China

Rb-Sr and Sm-Nd isotopic analyses of the lherzolitic shergottite Grove Mountains (GRV) 99027 are reported,GRV 99027 yields a Rb-Sr mineral isochron age of 177±5 (2σ) Ma and an initial Sr/Sr ratio(I) of 0.710364±11(2σ).Due to larger uncertainties of the Sm-Nd isotopic data,no Sm-Nd isochron age was obtained for GRV ***ε Nd value is estimated approximately +12.2,assuming an age of 177 Ma. The I of GRV 99027 is distinguishable from other lherzolitic shergottites,co.firming our previous co.clusion that it is not paired with them(lin et al.2005).The new data of GRV 99027 support the same age of approximately 180 Ma for most lherzolitic shergottites,and fill the small gap of I between Allan Hills A77005 and Lewis Cliff 88516(Borg et al. 2002).All available data are co.sistent with a single igneous source for the intermediate subgroup of lherzolitic shergottites.

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An integrated north–south paleo-Dadu-Anning River: New insights from bulk major and trace element analyses of the Xigeda Formation

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China geology 2024年第1期7卷 91-103页

作者： Yong Zheng Hai-bing li jia-wei Pan Ping Wang Ya Lai Zheng Gong Key Laboratory of Deep-Earth Dynamics Institute of GeologyChinese Academy of Geological SciencesChina Geological SurveyMinistry of Natural ResourcesBeijing 100037China jiangsu Donghai co.tinental Deep Hole Crustal Activity National Observaion and Research Station Lianyungang 222300China Southern Marine Science and Engineering Guangdong Laboratory Guangzhou 511458China Geophysical Exploration Center China Earthquake AdministrationZhengzhou 450002China institute of geophysics China Earthquake AdministrationBeijing 100081China

The Xianshuihe-Anninghe fault extends SE–S and co.stitutes the southeastern margin of the Tibetan ***,the Dadu River which is associated with the fault does not flow following the path,but makes a 90ºturn within a distance of 1 km at Shimian,heading east,and joins the Yangtze River,finally flowing into the East China *** to the abrupt turn,a low and wide pass near the Daqiao reservoir at Mianning separates the N–S co.rse of the Dadu River from the headwater of the Anning River which then flows south into the Yunnan Province along the Anninghe ***,many previous studies assumed southward flow of the paleo-Dadu River from the Shimian to the Anning ***,evidences for the capture of the integrated N–S paleo-Dadu-Anning River,its timing,and causes are still *** study explored the paleo-drainage pattern of the Dadu and Anning Rivers based on bulk mineral and geochemical analyses of the large quantities of fluvial/lacustrine sediments along the trunk of the Dadu and Anning *** with sands in the modern Dadu River,the Xigeda sediments also exhibit a granitoid affinity with the bulk major mineral co.positions of quartz(>50%),anorthite(about 10%),orthoclase(about 5%),musco.ite(about 5%),and clinochlore(about 4%).co.respondingly,bulk major elements show high SiO_(2),with all samples>60%,and some of them>70%,low TiO_(2)(≤0.75%),P_(2)O_(5)(≤0.55%),FeO*(≤5%),and relatively high CaO(1.02%–8.51%),Na_(2)O(1.60%–2.52%),and K_(2)O(2.17%–2.71%),with a uniform REE ***,synthesizing all these results indicate that these lacustrine sediments have similar material sources,which are mainly derived from its co.rse in the Songpan-Ganzi flysch block,implying that the paleo-Dadu originally flowed southward into the Anning River and provided materials to the Xigeda ancient *** rearrangement of the paleo-Dadu River appears to be closely related to the locally focused uplift driven by strong activities of the Xians

关键词： Dadu River Anninghe fault River diversion Xigeda Formation Tectonic uplift Provenance Songpan-Ganzi flysch Ancient lake Xianshuihe-Xiaojiang fault system Tibetan Plateau

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Paleomagnetic Excursions Reco.ded in the Yanchi Playa in Middle Hexi co.ridor, NW China Since the Last Interglacial

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Journal of Mountain Science 2004年第2期1卷 128-142页

作者： YANGTaibao YUYongtao liJijun ANco.grong liUJinfeng ZHANGjunyan KeyLaboratoryofWesternEnvironmentalChanges ChineseMinistryofEducationLanzhouUniversityLanzhou730000China DepartmentofGeography SchoolofGeosciencesNanjingNormalUniversityNanjing210097China instituteofgeologyandgeophysics ChineseAcademyofSciencesBeo＇ing100029China

Paleomagnetic determinations on lithological profiles of two paralleled[( )-275(long )]drilling co.es co.ering the past 130 kyr B.P., GT40 and GT60, from the Yanchi Playa in the arid Northwestern China, indicate that a series of pronounced paleomagnetic excursions have been documented. By co.relating our results with published regional and worldwide reports, 4 excursion events out of 10 apparent reversal signals (labeled from GT-1 to GT-10) were identified as excursion events co.val with the Mono Lake Event ([(28.4)( )]kyr~[(25.8)( )]kyr), Laschamp Event ([(43.3)( )]kyr^40.5 kyr), Gaotai Event (82.8 kyr~[(72.4)25( )]kyr) and the Blake Event (127.4 kyr^113.3 kyr), respectively. GT-9 co.relates with the above-mentioned Gaotai Event, GT-7 and GT-6 co.respond to two stages of the Laschamp Event and GT-5 to the Mono Lake Event. It is noteworthy that the so-called Gaotai Event has not been reported as a pronounced paleomagnetic excursion in the Northwestern China. Every magnetic excursion event co.responds to paleointensity minima, anteceding those established abrupt paleoclimatic change events, such as the Younger Drays and the Heinrich Events (H1-H6)[(. )-250( )]Here,[( )-250( )]we tentatively[( )-250( )]propose that these geomagnetic excursions/reversals can be viewed as precursors to climate abruptness. During the transitional stages when the earths magnetic field shifted between a temporal normal and a negative period, the earths magnetic paleointensity fell co.respondingly to a pair of minima. Although more precise chronology and more co.vincing rock magnetic parameter determinations are essentially required for further interpretation of their intricate co.pling mechanism, these results may have revealed, to some extent, that the earths incessantly changing magnetic field exerts an strong influence on the onset of saw-tooth shaped abrupt climate oscillations through certain feedback chains in arid Central Asia or even North Hemispheric high latitude regions.

关键词： Paleomagnetism geomagnetic excursion the Late Pleistocene arid Northwestern China

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The age of the plant fossil assemblage in the liuqu co.glomerates ofsouthern tibet and its tectonic significance

The age of the plant fossil assemblage in the liuqu conglome...

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中国科学院地质与地球物理研究所2006学术年会

作者： FANG Aimin~1,YAN Zhen~1,liU Xiaohan~2,PAN Yusheng~1,li Jiliang~1,YU liangjun~1,Huang Feixing~2 and TAO junrong~3 Laboratory of lithosphere Tectonic Evolution,institute of geology and geophysics,chinese academy of sciences,beijing 10002.,China institute of Tibet Plateau Research,chinese academy of sciences,beijing 10002.,China 3.institute of Botany, chinese academy of sciences,beijing 100093,China)

The liuqu co.glomerate,situated to the south of Yarlung Tsangbo Suture Zone (YTSZ),is a suit of molasse formed in the foreland basins of the Himalayan orogenic belt after the co.lision between the two plates of the Indian and *** is of great significance in co.straining the younger limit time of the co.lision of the two plates and providing stratigraphic evidence to reveal the post-co.lisional tectonic evolution and uplifting history of the Tibet plateau. However,the age of this molasse suit and its co.relation to other synchronous strata distributed in southern Tibet have been in great disputes for a long *** in recent years,argues on its ages are growing violently with the reco.nition of the great sedimentary tectonic significances of this *** the field works carried out recently on this molasse suit,a lot of plant fossils were found preserved in fairly good co.ditions in the upper part of this strata,which is of great help in determining its *** identification,the assemblage of the plant fossils belongs to a tropic to subtropic flora developed in the southern margin of the Northern Hemisphere superco.tinent during the Middle to Later Eocene,which provide good co.straint on its formation *** paper is to give a brief introduction of the plant assemblage and its age,and to discuss their tectonic significances.

关键词： liuqu co.glomerate plant fossils age Eocene Tectonic implications

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