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Hydrogen isotopic characteristics and their genetic relationships for individual n-alkanes in plants and sediments from Zoigê marsh sedimentary environment

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Science china Earth Sciences 2010年第9期53卷 1329-1334页

作者： DUAN Yi1, ZHENG ChaoYang2.& WU BaoXiang1 1 Key Laboratory of Petroleum Resources Research, institute of geology and {2., {{4. Academy of Sciences, Lanzhou 7{4.000, china 2.Department of geology, Northwest University, Xi’an 710069, china 1. Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China2. Department of Geology Northwest University Xi’an 710069 China

To understand internal relations of their hydrogen isotopic compositions in typical marsh environment, we, using GC-IRMS analytical technique, measured the hydrogen isotopes of individual n-alkanes in the herbaceous plant, woody plant leaf, and sediments from Zoigê marsh in china. The results show significant differences in the hydrogen isotopic compositions of n-alkanes among the different kinds of plants and the different species in the same kind. δD values of n-alkanes in the herbaceous plants (from -2.4. to -184.) are lighter than those in woody plant leaf ( from -195‰ to -14.1} ), and the hydrogen isotopic compositions of n-alkanes in K. tibetica P. are lighter than P. pratensis L. The mean δD values of n-alkanes in the sediments from Zoigê marsh reflect that they were derived from herbaceous plants, which is consistent with the peat samples being composed mainly of herbaceous plant remnants. The significant differences in hydrogen isotopic compositions of n-alkanes among the sedimentary samples are caused possibly by environment factors and the difference in input quantity of different herbaceous plants. A certain negative correlation exists between the δ13. and δD values of n-alkanes in the samples, and plant types can be distinguished using the cross plot of δD vs. δ13. values of n-alkanes in the plants. These data and recognitions provide scientific basis for hydrogen isotopic applied research of individual n-alkanes.

关键词： marsh environment plants sediments individual lipids hydrogen isotopes genetic relationship

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Magnetostratigraphy of Late Cenozoic fossil mammals in the northeastern margin of the Tibetan Plateau

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Science Bulletin 2003年第2期48卷 188-193页

作者： SONG Chunhui1,2.FANG Xiaomin 1,2.GAO Junping1, NIE Junsheng1,YAN Maodu1,3.XU Xianhai1 & SUN Dong1 1. MOE National Laboratory of Western china抯 Environmental Systems & College of Resource and Environment,Lanzhou University,Lanzhou 73.000,china 2. State Key Laboratory of Loess and Quaternary geology ,{3. of Earth Environment,chinese Academy of Sciences,Xi抋n 710075, china 3. Department of Geological Sciences,University of Michigan,AnnArbor,MI 4.109,USA Univ Arizona Steward Observ Tucson AZ 85721 USA MOE National Laboratory of Western china\'s Environmental Systems & College of Resource and Environment Lanzhou University Lanzhou 730000 China

A number of fossil mammals have been found in the very thick Cenozoic stratigraphy of the Guide Basin in the northeastern margin of the Tibetan *** of these are of great significance in mammal evolution and stratigraphic correla-tion on and around the Tibetan Plateau and North ***,the chronology of these mamals is poorly *** of the mammals will not only place precise age constraints on the mammals,but also provide much inlormation on the related stratigraphy that records the uplift process of the Tibetan *** paleomagnetism of the upper part of the Cenozoic stratigraphy at He'erjia and Lajigai north of Guide County has revealed magnetic chrons that can be correlated to Ganss and 3.n *** the section spanning about 3.16.5 Ma and the *** and third layers of fossil mammals at about 5.2.,5.1 and 4.4.Ma,*** of the significant genus Gazella kueitensis and the {2. elephant Anancus sinensis are firstly constrained at about 5.2. MaBP and 4.4.Ma,*** mammalian evolution and the associated increase in coarse sediments and sedimentation rate may suggest that the northeastern Tibetan Plateau was uplifted rapidly at that time,and the eastern Tibetan Plateau with its neighboring regions was not high enough to stop mammal exchange between the northern and southern sides of the Tibetan Piateau.

关键词： Tibetan Plateau Guide Basin Late Cenozoic stratigra-phy fossil mammals paleomagnetism.

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Indosinian Foreland Fold-and-Thrust Belt Bordering Yunnan and Guangxi, china

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 391-397页

作者： WU Genyao institute of geology and {2., {3. Academy of Sciences, Beijing {4. institute of geology and {2. Chinese Academy of Sciences Beijing 100029 [?]2.u Genyao Male born in 1946 graduated from the Department of geology Peking University in 1968 obtained a DSc degree in 1985 now a research professor with the institute of geology and {2. Chinese Academy of Sciences. His main research interest is regional tectonics and he has been working on the tethysides in South China and adjacent areas since 1987. Tel: (010) 62008118 Fax: (010) 62.1084. E-mail: dizhikx@***

Recent discoveries of ophiolites indicate that there must be a Palaeotethyan geosuture zone bordering china and Vietnam, which separates the Vietbac block from the South china subcontinent. The Indosinian foreland fold-and-thrust belt bordering Yunnan and Guangxi provided further evidence for the palaeotethysides. The oceanic crust was subducted southwestwards while the magmatic arc migrated northeastwards, and the continent-arc collision occurred in the Late Triassic with the thrusting being extended towards the north or northeast. The features of thrust-nappe structure are discussed, which proved the continental margin of the Palaeotethyan ocean there to be a complicated one. A face-to-face collision occurred first along the NW-striking segment and then along the ENE-striking segment accompanied by transpression or oblique thrusting occurring along the NW-striking one.

关键词： thrust-nappe structure foreland fold-and-thrust belt palaeotethysides border between Yunnan and Guangxi

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Nonlinear analysis on the coupling process of electromagnetic vibrator and earth

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Science china Earth Sciences 2005年第8期48卷 1175-1182页

作者： CHEN Zubin1,2. TENG Jiwen2. LIN Jun1, ZHANG Linhang1 & JIANG Zhongjin1 1. institute of Intelligent Instrument & Measurement Control Technology, Jilin University, Changchun 13.02.,{2. 2. institute of {3. & geophysics, chinese Academy of Sciences, Beijing 10002.,{2. 1. institute of Intelligent Instrument & Measurement Control Technology Jilin University 130026 Changchun China 2. institute of geology & {2. Chinese Academy of Sciences 100029 Beijing China

The linear model based on the hydraulic pressure vibrator has been no longer adaptable to the electromagnetic vibrator. In order to realize the effective transmission of the limited energy from the vibrator to the ground, it is important to study the coupling model of the electromagnetic vibrator and the earth. In this paper, a nonlinear restore term was introduced to the coupling model because of the existence of a large amount of harmonics in the vibrator baseplate. The nonlinear vibration analysis was applied to the model by the multiscale method. In the course of energy transmission from the vibrator to the ground, ultraharmonic resonance was used to explain the generation of harmonics. An improved scheme was advanced to select the cross correlation reference signal in the vibrator seismic exploration. Good application results were obtained in field experiments.

关键词： vibrator, coupling model, electromagnetic, nonlinear vibration.

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A New SHRIMP Age of the Xiamaling Formation in the North china Plate and Its Geological Significance

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Acta Geologica Sinica(English Edition) 2007年第6期81卷 1103-1109页

作者： GAO Linzhi~(1,*)ZHANG Chuanheng~2.SHI Xiaoying~2.ZHOU Hongrui~2.WANG Ziqiang~2.SONG Biao~(1,{4. 1 institute of {2.,chinese Academy of Geological Sciences,Beijing 1000{4.,{{4. 2.6} University of Geosciences(Beijing),Beijing 10008{4.{{4. {4.Beijing SHRIMP Central,1000{4. Beijing,{{4. institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

Setting up the hypostratotype of late Precambrian is the main aim of the research on the Meso-and Neoproterozoic in North *** chronostratigraphic position is the key in this study. However,many key horizons have not been calibrated with the high-quality isotopic *** the reported new U-Pb age with the Sensitive High-Resolution Ion Microprobe（SHRIMPⅡ）,a zircon U- Pb age was obtained of the ash bed in the Xiamaling Formation in North china Plate,yielding a weighted mean;Pb/;U age of 13.8±12.*** is the first SHRIMP U-Pb age from the Xiamaling Formation in the North china Plate,and represents the depositing time of the middle part of the Xiamaling *** zircon age plays an important role to understanding geological evolution of the North china Plate during Meso-and Neoproterozoic.

关键词： SHRIMP U-Pb Dating Mesoproterozoic Xiamaling Formation North china Plate

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A finite difference study on the basement structure beneath the Tianshan Orogen

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Science china Earth Sciences 2004年第Z2期47卷 16-23页

作者： ZHAO Junmeng1,2. WANG Qingchen3. GAO Xing1, DUAN Yonghong4. JIA Shixu4.& PAN Shuzhen4.1. institute of Tibetan Plateau Research, {2. Academy of Sciences, Beijing 100085,{4. 2. institute of geology,{4. Seismological Bureau, Beijing 10002.,{4. 3. institute of geology and geophysics, {2. Academy of Sciences, Beijing 10002.,{4. 4. Geophysical Exploration Center,{4. Seismological Bureau, Zhenzhou 4.0002.{4. institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China institute of geology China Seismological Bureau Beijing 100029 China institute of geology and {2. Chinese Academy of Sciences Beijing 100029 China institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China Geophysical Exploration Center China Seismological Bureau Zhenzhou 450002 China

We use the Pg seismic phase along the Korla-Jimsar profile across the Tianshan orogen and the 3. finite difference method to inverse the velocity structure of the upper crust beneath the basement of this mountain. Based on the velocity structure, the Korla-Jimsar profile can be divided into three parts, i.e. the north edge of the Tarim basin, the Tianshan orogen, and the south margin of the Junggar basin. Within the Tianshan there is a pattern of four convexities and three concavities, which correspond to the southern Tianshan, the Yanqi basin, the middle Tianshan, the Turpan basin, and the Bogda Mountains. In the north edge of the Tarim basin, the basement is about 10km deep with small lateral variations of velocity. In the Tianshan the velocity varies greatly laterally. The basement depth of the Yanqi basin is 6 km, which becomes shallow rapidly northward, and almost to the surface at the middle Tianshan. South to Kumux there is a small intermountain basin, where the maximum basement depth is 3.km, and also turns very shallow near Kumux. The Luntai fault, which bounds the Tarim basin and Tianshan, has vertical dislocation of about 5 km. The Turpan basin is covered with so thick a sediment that its basement is 7 km deep. The boundary fault between the Tianshan and Turpan is the Bolohoro fault which is characterized by quick deepening basement and 7 km vertical dislocation. In the Junggar basin the basement is 8 km deep. On the Korla-Jimsar profile, the velocity distribution of the upper crust and the structure are featured by NS symmetry on both sides of the axis of the Middle Tianshan, consistent with the deep structure revealed by this profile. It means that the Tarim ba-sin and the Junggar basin underthrust toward the Tianshan from south and north, respectively. Such a structural style is different from that of another profile, i.e. the Xayar-Burjing profile, sug-gesting that there may be an important tectonic boundary between these two profiles.

关键词： finite difference, Tianshan orogen, structure of the upper crust.

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Lithospheric seismic fabrics of Sulu ultrahigh-pressure metamorphic belt

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Science china Earth Sciences 2005年第5期48卷 585-600页

作者： YANG Wencai 1 , YANG Wuyang 1 , JIN Zhenmin 2.& CHENG Zhenyan 1 1. institute of geology, {2. Academy of Geological Sciences, Beijing 1000{4.,{{4. 2.{{4. University of Geosciences, Wuhan 4.4.074.{{4. 1. chinese Academy of Geological Sciences Institute of Geology 100037 Beijing China 2. china University of Geosciences 430074 Wuhan China

Calibration of seismic reflectors appearing in the crust of the chinese continent sci- entific drilling site can be completed through the correlation studies between direct evidences, such as the drill cores, and geophysical signatures; therefore the interpretation of geophysical data could produce reliable results of crustal structure and composition. On the other hand, there are two Cenozoic volcanoes close to the scientific drilling site; analyzing composition of xenoliths existent in the volcanoes and evaluating their seismic velocities can also offer information about the mantle and lower crust. After the calibration via cores and well-logging data, the seismic re- flectors appearing in the UHP belt can be caused by lithological changes within the UHP rock slice, ductile shearing rock-suites, and later fracture zones. Among these sources, ductile shearing resulted in displacement and detachment of original rock-sheets, producing some rock-interbeds of several hundred meters thick that are named the ductile shearing rock-suites. A suite consists of mylonized gneiss and eclogite slices that underwent shearing, becoming the major mechanism responsible to generate regional strong reflections. The UHP rock-slice is characterized by complicated structures and high density, high seismic velocity and high electri- cal resistivity, its thickness is usually less than 11 km. Velocity and density of the gneiss-layer beneath gradually tend to normal with increasing depth. Based on the xenoliths we can infer that the middle crust contains a lot of gneisses, and the lower crust consists of different granulites. The lithospheric mantle has multi-layer structures and consists mainly of spinal lherzolite and harzburgite, implying late Mesozoic lithospheric thinning. The seismic fabrics with different ori- gins were possible products of different geodynamic processes. For instance, the UHP rock-slice was produced by the UHP metamorphic process and the exhumation of subducted supe

关键词： deep seismic reflection, ultrahigh-pressure belt, Sulu china, calibration of reflectors, lithospheric fabrics.

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Reinterpretation of the Guangxian Orogeny

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chinese Science Bulletin 2000年第13期45卷 1244-1248页

作者： WU Haoruoinstitute of geology and {2., {3. Academy of Sciences, Beijing {4., china institute of geology and {2. Chinese Academy of Sciences Beijing China

The Guangxian Orogeny, as an important concept on geology of South china, was created 70 years ago. It is generally regarded as an erogenic movement caused by the convergence of the Cathaysian and Yangtze blocks at the end of Silurian. Based on the recent progress of the geological research on Guangxi and adjacent areas, western Guangxi and Liuzhou-Heshan area of central Guangxi may belong to a stable block of Early Paleozoic. The Guangxian Orogeny originated from the northward translation of the Yunkai Block on its south at the end of Cambrian, and formed the Damingshan-Dayaoshan fold belt between the two blocks. It was possibly related with the Late Pan-African Orogeny. The convergence of the Cathaysian and Yangtze blocks occurred in Late Ordovician to Early Silurian and mainly had effect on Hunan and Jiangxi provinces. The term 'Chongyu Orogeny' may be suitable for it. At the end of Silurian orogenic movement did not occur in this area.

关键词： South china tectonics Paleozoic Guangxian Orogeny Yunan Orogeny Chongyu Orogeny.

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Geological analysis and physical modeling of structural pumping in high effective formation of Kela 2.gas field

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Science china Earth Sciences 2006年第10期49卷 1070-1078页

作者： ZHAO Wenzhi1, WANG Hongjun1, SHAN Jiazeng2. WANG Zecheng1 & XU Dafeng1 1. Research institute of Petroleum Exploration and Development, Petrochina, Beijing 10008{2.{4. 2. institute of geology and geophysics, chinese Academy of Sciences, Beijing 10002.,{4. 1. Research institute of Petroleum Exploration and Development Petrochina Beijing 100083 China 2. institute of geology and {2. Chinese Academy of Sciences Beijing 100029 China

In a 3.D closed geological body, in case “structural expanding” inside is induced by stress, it can produce the pressure difference between the expanding cell and surrounding rock, then generate a pumping force directed toward the cell and accelerate the directional flow of fluid in the strata. The structural style and conditions of gas reservoir-formation in the Kuqa depression are favorable to the structural pumping. According to similarity principle, a physical modeling of structure formation and gas filling process of the Kela 2.gas field has justified the occurrence of structural pumping and its important role in gas-reservoir formation with high efficiency under the compressive and well-sealed circumstance. Therefore, authors propose that structural pumping is an important mechanism of gas reservoir-formation with high efficiency in the Kuqa depression.

关键词： Kela 2 gas field, structural pumping, gas-reservoir formation mechanism, high efficiency,physical modeling.

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Carbon isotopic variations of Proterozoic carbonates in Jixian, Tianjin, china

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Science china Earth Sciences 2004年第2期47卷 160-170页

作者： CHU Xuelei, ZHANG Tonggang, ZHANG Qirui, FENG Lianjun & ZHANG Fusong1. institute of geology and {2., {3. Academy of Sciences, Beijing {4., china 2. Key Laboratory for Mineral Resources Research, {3. Academy of Sciences, Beijing {4., china Correspondence should be addressed to Chu Xuelei (email: xlchu@***) 1. institute of geology and {2. Chinese Academy of Sciences 100029 Beijing China 2. Key Laboratory for Mineral Resources Research Chinese Academy of Sciences 100029 Beijing China

Along the Proterozoic stratigraphic sections of Jixian, Tianjin, the ??13. values of carbonates are mostly negative in the Changchengian (Changcheng System), varying approximately within a range of (0±1)‰ in the Jixianian (Jixian System), and have commonly positive values of (2.2.‰ in the Qingbaikouan (Qingbaikou System). From Chuanlinggou Formation to Dahongyu Formation, i.e. from ca. 1700 Ma to 1600 Ma, the δ13. values of carbonates increase from about -3. to 0‰, but oscillate with large excursion in Dahongyu Formation. Two large excursions occur in the Jixianian, one in Yangzhuang Formation and the other in the third submember of Wumishan Formation overlaying. These integrated and continuous records of carbon isotope reflect secular variations of δ13. value in ancient seawater from ca. 1700 Ma to ca. 800 Ma. The increase and subsequent oscillation of seawater δ13. value occurring from the ages of ca. 1700 to ca. 1600 Ma and ＜13.0 Ma may signify two correlative global tectonic events.

关键词： Proterozoic, Jixian, carbon isotope, chemostratigraphy, secular variation, global tectonic event.

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