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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： LI Dong & HAN JingTai~* key Laboratory of cenozoic geology and environment,institute of geology and geophysics,chinese academy of sciences,beijing 10002., china

Diatom oxygen isotopes have been widely applied in quantitative reconstruction of the paleoclimate and paleoenvironment,but have rarely been reported in *** the present study,Lake Sihailongwan in Northeast china was selected for detailed investigation of oxygen isotopic fractionation between diatom frustules and lake water induced by growth *** study involved a 2-year period of field monitoring of the lake water temperature at multiple depths and biweekly collections of traps for both sediment and water at shallow and bottom depths(7 and 49 m below the lake surface,respectively),diatom separation and purification of the trap sediments,and oxygen isotope measurement for diatom silica and lake water *** conditioned experiment conducted herein demonstrated that the laboratory device,methods and techniques used in this study were capable of generating reliable data for the typical oxygen isotope composition of diatom *** data obtained revealed a prominent linear relationship between the oxygen isotope composition of the modern diatom and lake temperature during *** fractionation coefficient was about -0.185‰/℃-0.238‰/℃in the temperature range of 3.6-24℃,which is consistent with the observations from various aquatic environments and laboratory culture with different diatom *** findings provide strong support for the dominant control of the growth temperature on the oxygen isotope fractionation between the diatom frustules and ambient water.A notable difference in the fractionation coefficient was observed between the surface and bottom diatom oxygen isotopes,suggesting that various depositional processes and taphonomic effects influenced the surface and bottom trap samples. Another factor leading to this difference may be that enrichment by evaporation and dilution by rainfall have a stronger influence on the ***,the results presented here demonstrate significant progress in evaluation of diatom oxygen isotope

关键词： diatom silica oxygen isotope isotopic fractionation Lake Sihailongwan Northeast china

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Advance-retreat history of the East-Asian summer monsoon rainfall belt over northern china during the last two glacial-interglacial cycles

Advance-retreat history of the East-Asian summer monsoon rai...

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中国科学院地质与地球物理研究所2008学术年会

作者： Shiling Yang~*,Zhongli Ding key Laboratory of cenozoic geology and environment,institute of geology and geophysics,chinese academy of sciences,beijing 10002.,china

In northern china,the history of desert migration provides a good measure of the East-Asian summer monsoon variations,since the desert margin environment is very sensitive to changes in summer monsoon *** margin migration can be well documented in the downwind loess deposits,since the grain size of chinese loess is principally controlled by source-to-sink distance and hence the loess grain size is an effective proxy for reconstructing the history of the East-Asian summer *** order to investigate the pattern and migration of the summer monsoon rainfall belt over northern china during the past two glacialinterglacial cycles,contour maps of loess grain size were constructed for MIS 2,3,4,5,6 and *** the grainsize isolines show a near north-south gradient for both glacials and interglacials,indicating a dominant dust source region in north and an approximately north-south dust transport pathway for dust deposits in the main body of the Loess Plateau,at least for the past two glacial-interglacial *** reconstructed southeast desert margin for MIS 2,3,4,5,6 and 7 roughly parallels the present isohyets,implying that the pattern of the East-Asian summer monsoon rainfall belt during the past two glacial-interglacial cycles is similar to the present,i.e.a northeast-southwest trend for the isohyets of the summer monsoon,despite the glacial-interglacial *** the grain-size isolines of MIS 2 as a reference,we derive a northerly desert retreat of～160 km,～19 km,～225 km and～223 km for MIS 3,4,5 and 7,respectively,and a southerly desert advance of～29 km for MIS 6,that could be preliminarily regarded as the relative migration distance for the East-Asian summer monsoon rainfall belt In addition,the inferred climate conditions in MIS 3 are cool and humid in northern china,while the driest and coldest interval of the last two glacial periods occurs in MIS 6.

关键词： East-Asian summer monsoon rainfall belt chinese loess grain size Mu Us desert glacial-interglacial cycle

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The developmental trend of labrum and median eyes of Orsten-type preserved Phosphatocopina (Crustacea)

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Science china Earth sciences 2010年第1期53卷 18-26页

作者： LIU Zheng 1,2 & DONG XiPing 1,2 1 School of Earth and Space sciences,Peking University,beijing 100871,china 2 State key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of geology and Palaeontology,chinese academy of sciences,Nanjing 210008,china School of Earth and Space sciences Peking University Beijing China State key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

The Phosphatocopina (Crustacea,Arthropoda) is an important group of 'Orsten-type' preserved *** is resolved as the sister-group of *** we study the labrum,the median eyes,and the inner lamella of Phosphatocopina based on the selected specimens respectively from western Hunan,South china,and *** labrum characters of different species exhibit interspecific *** ratio of labrum length/shield length is significant to the reconstruction of the ontogeny of *** labrum characters should be introduced to the diagnosis of *** the earliest growth stage,the median eyes were inconspicuous,almost as flat as the other area of the ***,with the growth of the individuals they became *** were two obviously concave structures on the ventral side of the hypostome in later stages,which were the positions where the median eyes should have been *** addition,the two modes of preservation of the inner lamella,i.e.,that of shrinking and that of bulging up,are interpreted as the preservational artifact herein.

关键词： Phosphatocopina Crustacea Orsten-type preservation morphology ontogeny Cambrian South china Sweden

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A 20 Ma pollen record of East-Asian summer monsoon evolution from Guyuan,Ningxia,china

A 20 Ma pollen record of East-Asian summer monsoon evolution...

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中国科学院地质与地球物理研究所2008学术年会

作者： Hanchao Jiang ~*,Zhongli Ding key Laboratory of cenozoic geology and environment,institute of geology and geophysics,chinese academy of sciences,beijing 10002.,china

Pollen analysis was conducted on the fluviolacustrine sediments from the east side of the Liupan Mountains, a relatively monsoon-sensitive region,and provided for the first time a continuous evolutionary history of vegetation and climate in East china during the *** pollen record spanning the last 20 Ma indicates that the vegetation and thus East-Asian summer monsoon evolution can be divided into three stages:20.13- 14.25 Ma,14.25-11.35 Ma and 11.35-0.08 Ma,in spite of general dominance of steppe throughout the *** the period 20.13-14.25 Ma,the pollen assemblage was characterized by high abundance of Artemisia and small amounts of temperate to subtropical deciduous broad-leafed trees such as Juglans,Carya, Quercus and Betula,suggesting that the East-Asian summer monsoon was generally *** interval from 14.25 to 11.35 Ma was marked by a significant decline in the East-Asian summer monsoon,as indicated by Artemisia gradually replaced by Humulus and halophytic *** and Ephedra also reached high values in this *** 11.35 Ma ago,percentages of halophytes dominated by Chenopodiaceae and Tamaricaceae maintained a high mean value of about 40%,revealing a weak intensity of East-Asian summer *** general weakening of the monsoon circulation during the Neogene and the significant monsoon decline during the late Middle Miocene in particular might link with the global cooling trend probably through two *** and ice-sheet expansion over the polar region caused an increase in meridional temperature gradients leading to the southward retreat of the monsoon *** global cooling may have also reduced the amount of water vapor held in the atmosphere,and led to both additional cooling and further weakening of the East-Asian summer *** cause for a short-lived resumption during the period 1.0-0.8 Ma is under investigation.

关键词： Pollen East-Asian monsoon Neogene Fluviolacustrine sediments Sikouzi Ningxia

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The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science china Earth sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, Lü Qingtian3, LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4 1. institute of geology and geophysics, chinese academy of sciences, beijing 10002., china 2. institute of geophysics, china Seismological Bureau, beijing 100085, china 3. institute of Deposition Resource, chinese academy of Geo{12., beijing 100037, china 4. School of Exploration and Information, china University of Geo{12., beijing 100083, china institute of geology and geophysics Chinese Academy of Sciences Beijing China institute of geophysics China Seismological Bureau Beijing China institute of Deposition Resource Chinese Academy of Geosciences Beijing China School of Exploration and Information China University of Geosciences Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, china. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3 segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2 km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2 segments. In the studied area, crustal thickness is about 40 km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

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Seismic multi-arch structures in East china

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Science china Earth sciences 2006年第2期49卷 133-146页

作者： YANG Wencai1 & CHEN Zhide2 1.institute of geology, chinese academy of Geological sciences, beijing 100037, china 2.Daqing institute of Petroleum Exploration and Production, Daqing 163712. china institute of geology Chinese Academy of Geological Sciences Beijing China Daqing institute of Petroleum Exploration and Production Daqing China

In previous papers (Wencai, 2002, 2003), the author has analyzed the deep seismic reflection profiles along some of the Mesozoic plutons in East china, and has pointed out that the crustal structures around these intrusions usually correlate with a special seismic fabric called the seismic multi-arch structure. This paper will continue to show main characteristics of the seismic multi-arch structures and discuss their relationship with mantle-origin magmatism and the lithospheric thinning process. Calibration of seismic reflectors in chinese continental drilling sites shows that small-scale arch-like reflectors can be generated by fractured eclogites or other plutons, they do not belong to the multi-arch structure specially discussed in the paper. The multi-arch structure is char-acterized by several arch-like reflectors distributed in both the upper and lower crust with granitoid plutons or stocks exposed on the surface, which do not have obvious negative Europium anomalies. Based on the distribution pattern of arch reflectors, the multi-arch magmatic structures can be divided into three main types, namely the simple vertical combination type, the spread arch magmatic struc-ture and the arch-bouquet structure. All of them correlate to mantle-origin magmatism, but occur in different places. The spread arch magmatic structures occur within a Mesozoic/cenozoic rift zone with very thin and hot lithosphere. The vertical combination type of the multi-arch structures occurred near the rift zones where lithosphere was thin and hot. The arch-bouquet magmatic structures occur far from the rift zones where the lithosphere is not hot. The continental rifting acted as the late episode of the lithospheric thinning process seeing that the rift zones usually coincide with the thinnest parts of the lithosphere in East china. In different locations within the lithospheric thinning areas, mantle-origin magmatic activities have different characteristics, which might generate different

关键词： deep seismic reflection, multi-arch structure, eclogite bodies, mantle-origin magmatism, East china.

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Serpentinization of peridotites from the southern Mariana forearc

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Progress in Natural Science:Materials International 2009年第10期19卷 1287-1295页

作者： Xiaomei Wang a,b,Zhigang Zenga,Junbing Chenc a key Laboratory of Marine geology and environment,institute of Oceanology,chinese academy of sciences,7 Nanhai Road,Qingdao 266071,china b Graduate School of chinese academy of sciences,19 Yuquan Road,beijing 100049,china c Geological Brigade of Hydrogeology and Engineering geology,Zhejiang Geological Prospecting Bureau,206 Baoshan Road,Ningbo 315012.china key Laboratory of Marine geology and environment Institute of Oceanology Chinese Academy of Sciences 7 Nanhai Road Qingdao 266071 China Graduate School of chinese academy of sciences 19 Yuquan Road Beijing 100049 China Geological Brigade of Hydrogeology and Engineering geology Zhejiang Geological Prospecting Bureau 206 Baoshan Road Ningbo 315012 China

A detailed petrologic and mineralogic study was carried out on serpentinized peridotites dredged from the southern landward slopes of the Mariana Trench,in order to reveal the serpentinization process of these unusual rocks and to identify the sole presence of the mineral *** constituent minerals of these southern Mariana forearc peridotites are olivine,amphibole and spinel,as well as serpentine,chlorite and *** with serpentinite seamounts,the serpentinized peridotites from the southern Mariana forearc are characterized by the absence of magnetite and brucite,and the common presence of talc;besides,the serpentine mineral variety is simplex,only *** mineral chemistry and mineral phase relationships,we conclude that(1) the absence of magnetite in the serpentinized peridotites is due to incomplete serpentinization,other than magnetite,the iron end-member in olivine forms Ferich brucite and Fe-rich serpentine;(2) brucite is not stable with high silica activity,reacting with later SiO2-rich fluid and then forming lizardite,leading to a lack of brucite in these serpentinized peridotites;(3) the occurrence of talc is the result of later SiO2-rich fluid reactions with lizardite;and(4) the reason for the sole occurrence of lizardite is that the temperature condition of our study are awas nothig henough for the formation of antigorite(whichisstable at >500 °C).Despite the broad overlap of lizardite and chrysotile in growth temperature,differences in the modes of occurrence of lizardite and chrysotile,such as the scarcity of H2O,low porosity and permeability,as well as the actual situation of initial serpentinization in the study area,result in the absolute prevalence of lizardite over chrysotile in the area.

关键词： Peridotite Serpentinization Mineral chemistry Lizardite Mariana

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Elemental and isotopic compositions of the hydrothermal sulfide on the East Pacific Rise near 13°N

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Science china Earth sciences 2010年第2期53卷 253-266页

作者： ZENG ZhiGang1,CHEN DaiGeng1,2,YIN XueBo1,WANG XiaoYuan1,ZHANG GuoLiang1,2 & WANG XiaoMei1,2 1 Seafloor Hydrothermal Activity Laboratory of the key Laboratory of Marine geology and environment,institute of Oceanology,chinese academy of sciences,Qingdao 266071,china 2 Graduate School of chinese academy of sciences,beijing 100049,china Seafloor Hydrothermal Activity Laboratory of the key Laboratory of Marine geology and environment Institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of chinese academy of sciences Beijing China

The mineralogical,elemental,and isotopic characteristics of a hydrothermal sulfide sample from one dredge station (12.42.30’N,103°54.48’W,water depth 2655 m) on the East Pacific Rise near 13°N were *** hydrothermal sulfide was composed mainly of sphalerite,chalcopyrite,and pyrite and was a Zn-rich sulfide;in layer ep-s-1,goethite formed by secondary oxidation was *** concentrations of rare elements,such as Li (0.15×10-6-0.30×10-6),Be (0.01×10-6-0.05×10-6),Zr (73.8×10-9-1344×10-9),Nb (8.14×10-9-64.7×10-9),Hf (2.54×10-9-28.0×10-9),and Ta (0.203×10-9-1.21×10-9),were far lower in the hydrothermal sulfide than in the ocean crust,whereas the content of Au was higher and the contents of Co,Ni,Sr,Cs,Ba,Bi,and U were *** correlations between Zn and Cr,Cd and Ga,Cu and P,P and In (R2 > 0.8) were positive,whereas those between Zn and Fe,Cu,and Ba (R2 > 0.8) were distinctly *** low-temperature mineral assemblages to high-temperature mineral assemblages,the spatial distributions of dispersive and rare elements (***,Li,Cs) in the hydrothermal sulfide displayed corresponding *** variations observed in some elements (e.g.,Cd,Cs,P) are controlled by Zn,Fe,and Cu sulfides,*** weathering accounts for the enrichment of V,Mn,and rare earth elements (REE) in the henna sulfide-oxidation layer that bears the secondary oxide mineral,leading to identical REE patterns for this layer (ep-s-1) and *** weathering also distinctly affects the correlations between the element ratios of the hydrothermal *** high-temperature mineral assemblages to low-temperature mineral assemblages,Fe content and δ 34S value of the hydrothermal sulfide increase gradually,and Zn content and lead isotopic ratios decrease gradually on the contrary,which indicate the influences of seawater on elements and the sulfur and lead isotopic compositions enhance gradually during the formation of hydrothermal sulfides.

关键词： variation element isotopic composition hydrothermal sulfide East Pacific Rise 13oN

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cenozoic COLLISIONAL DEFORMATION AND LITHOSPHERE TECTONIC EVOLUTION OF THE EASTERN HIMALAYAN SYNTAXIS

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地学前缘 2000年第S1期7卷 12-13页

作者： Ding Lin, Zhong Dalai, Zhang Jinjiang, Ji Jianqing(institute of geology and geophysics, chinese academy of sciences, beijing 10002.,china)

The Eastern Himalayan Syntaxis (EHS) is one of the strongest deformation area along the Himalayan belt resulted from the collision between Indian plate and the Eurasian plate since 50～60Ma, and has sensitivity tracked and preserved the whole collisional processes. It should depend on the detail geological investigations to establish the deformational accommodate mode, and the uplift history, to elucidate the deep structure and the crust\|mantle interaction of the EHS. The Namjabarwa metamorphic complex indented into the Gangdise arc along the sinistral Pai shear fault and the dextral Aniqiao shear fault on the both sides of the Great Canyon of Yalung Zangbo river since the collision of the NE corner of the Indian plate and the Eurasian Plate at 60～70Ma [1] . The distance between Yarlung Zangbo suture and Bangong—Nujiang suture is shortened more 12.km in the EHS area than that of the Lhasa block.

关键词： Eastern Himalayan Syntaxis collisional deformation Magmatism and high\|pressure metamorphism Lithospheric evolution

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Thrust Propagation in the Aqqikkol Lake Area, the East Kunlun Mountains, Northwestern china

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Acta Geologica Sinica(English Edition) 2003年第4期77卷 468-478页

作者： CUI Junwen, CHEN Wen, LI Pengwu, ZHANG Xiaowei and LI Li institute of geology, chinese academy of Geological sciences, beijing 100037 chinese Acad Geol Sci Inst Geol Beijing 100037 Peoples R China

The western segment of the East Kunlun Mountains is one of the poorly studied regions in northwestern china. Through a structural analysis of the typical sections, we have the following views: (1) There is a very well developed fault system in the western segment of the East Kunlun Mountains and thrust propagation, normal slip and decoupling are the chief deformation events in this area. (2) Although the thrusting started in the Late Carboniferous and Late Triassic-Early Jurassic, strong activity took place in the Miocene-Quaternary when the Kumkol basin was strongly downwarped. (3) The tectonic pattern of coexistence of N-directed thrust propagation and S-directed normal slip in this area is consistent with the general tectonic pattern of the northern Qinghai-Tibet plateau and also very similar to that of the Himalayan region on the southern margin of the Qinghai-Tibet plateau, but their directions between the thrust propagation are opposite and all the strong thrust propagations occurred from the Miocene-Pliocene to Quaternary, a period featuring strong collision between the Indian plate and the Eurasian plate and abrupt uplift of the Qinghai-Tibet plateau. This oppositely directed thrust propagation and normal slip reveal such kinematic characteristics as symmetric propagations of deep-seated materials towards the north and south beneath the Qinghai-Tibet plateau and gravitational sliding of superficial materials towards the interior of the plateau. Therefore, the establishment of the fault system in the study area may provide an approach to the study of deep processes of the northern Qinghai-Tibet plateau and the construction of a unified geodynamic model for the uplift of the Qinghai-Tibet plateau.

关键词： western segment of the East Kunlun Mountains thrust propagation normal slip plate collision dynamic model

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