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chinese Science Bulletin 2006年第14期51卷 1736-1740页

作者： SONG Zhiguang1,2.& WANG Cuiping1,3.. State key laboratory of Organic {2., guangzhou institute of geochemistry,{3., China 2. guangzhou Research Center of Gas Hydrate,{3., China 3. Graduate School of chinese academy of sciences. Beijing 10003., China State key laboratory of Organic {2. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China guangzhou Research Center of Gas Hydrate Chinese Academy of Sciences Guangzhou China Graduate School of chinese academy of {2. Beijing China

A group of 2.6,10,15,19-pentamethyli- cosenes (PMIΔ) containing 1―5 unsaturated double bonds has been identified in the sea floor sediments from the Gulf of Mexico at the Green Canyon 2.8 *** PMIΔ compounds are distributed between nC2. and nC2. on the mass chromatogram of aliphatic fraction. Their δ 13. values are very much depleted in 13. and in the range of ?86.7‰ to ?115.5‰, whereas the δ 13. values of companion n-alkanes range from ?2..4‰ to ?3..6‰. These unsaturated PMIΔ com-pounds are typical biomarkers derived from the an-aerobic oxidation of methane mediated by meth-ane-oxidizing archaeal bacteria and indicative of the gas seeps or even the occurrence of gas hydrates in the deep sea sediments.

关键词：生物标志墨西哥湾沉积物 PMIA 天然气水化物

Research on the dynamics of the South China sea opening:Evidence from analogue modeling

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Science China Earth sciences 2006年第10期49卷 1053-1069页

作者： SUN Zhen1,2. ZHOU Di1, ZHONG Zhihong3. XIA Bin2. QIU Xuelin1, ZENG Zuoxun4 & JIANG Jianqun5 1. cas {3. {2. of marginal sea geology, South China sea {3. of Oceanology, chinese academy of sciences. {13. 5103.1, China {12., guangzhou institute of geochemistry, chinese academy of sciences. guangzhou 510640, China 3. Department of Technology, Shenzhen Branch of CNOOC, {13. 5102.0, China 4. Faculty of Earth sciences. China University of Geosciences. Wuhan 43.074, China 5. Hainan Oil & Gas Exploration Company, Liaohe Oilfield PetroChina, Panjin 12.010, China cas key {2. of {3. sea geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China cas key {2. of {3. sea geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Department of Technology Shenzhen Branch of CNOOC Guangzhou China Faculty of Earth sciences China University of Geosciences Wuhan China Hainan Oil & Gas Exploration Company Liaohe Oilfield PetroChina Panjin China

Independent of Indochina extrusion, the South China sea experienced a process from passive continental rifting to marginal sea drifting. According to the fault patterns in the Beibu Gulf basin and the Pearl River Mouth basin, the continental rifting and early spreading stage from 3.3.to {3. Ma were controlled by extensional stress field, which shifted clockwise from southeastward to south southeastward. From {3. Ma on, the sea spread in NW-SE direction and ceased spreading at around 15.5 Ma. Integrated geological information with the assumption that the South China sea developed along a pre-Cenozoic weakness zone, we did analogue experiments on the South China sea evolu- tion. Experiments revealed that the pre-existing weakness zone goes roughly along the uplift zone between the present Zhu-1 and Zhu-{3.depression. The pre-existing weakness zone is composed of three segments trending NNE, roughly EW and NEE, respectively. The early opening of the South China sea is accompanied with roughly 15° clockwise rotation, while the SE sub-sea basin opened with SE extension. Tinjar fault was the western boundary of the Nansha block (Dangerous Ground), while Lupar fault was the eastern boundary of the Indochina, NW-trending rift belt known as Zengmu basin developed between above two faults due to block divergent of Indochina from Nansha. In the experiment, transtensional flower structures along NW-trending faults are seen, and slight inversion occurs along some NE-dipping faults. The existence of rigid massifs changed the orientations of some faults and rift belt, and also led to deformation concentrate around the massifs. The rifting and drifting of the South China sea might be caused by slab pull from the proto South China sea subducting toward Borneo and/or mantle flow caused by India-Asia collision.

关键词： South China sea, rifting and drifting, clockwise rotation, analogue modeling, rigid massifs.

Magnetic properties of Jiaxian red clay sequences from northern chinese Loess Plateau and its paleoclimatic significance

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Science China Earth sciences 2005年第8期48卷 1234-1245页

作者： QIANG Xiaoke, AN Zhisheng, LI Huamei, CHANG Hong & SONG Yougui 1. SKLLQG, institute of Earth Environment, chinese {2. of {3. Xi’an 710075, China 2. guangzhou institute of geochemistry, chinese academy of sciences. guangzhou 510640, China chinese academy of {2. SKLLQG Institute of Earth Environment Xi’an China chinese academy of {2. Guangzhou Institute of Geochemistry Guangzhou China

Detailed rock magnetism investigation of the Jiaxian red clay sequences indicated that there are common magnetic mineralogy properties in red clay and loess-paleosol sequences from the chinese Loess Plateau as well as the marked properties of themselves, magnetic min-erals mainly with magnetite, maghemite, hematite, and possibly limonite/goethite contributing to the magnetic behavior. Meanwhile, it is found that the strong paleosol in red clay sequences has a lower coercivity and higher content of ultra-fine ferrimagnetic grains than that of the weak pa-leosol, which is similar to loess and paleosol in upper Wucheng Loess sequences, and indicates that humid conditions and relatively strong pedogenesis play a significant role in the increase of ultra-fine magnetic minerals and transformation of the magnetic minerals. This suggests that, like Quaternary loess-paleosols, the change of characteristics of paleoclimatic conditions of the late Tertiary red clay deposits is fluctuant. In addition, the results of magnetic hysteresis properties show that the applied saturated field for samples from the Jiaxian red clay sequences is higher than that of the samples from eastern and southern chinese Loess Plateau. It is obviously shown that there exist more hard magnetic minerals and relatively weak biochemical processes in the Jiaxian red clay sequences on northern chinese Loess Plateau. We conclude that the paleocli-matic environment is different between northern and eastern/southern chinese Loess Plateau, and it should be more arid in northern chinese Loess Plateau.

关键词： northern chinese Loess Plateau, red clay, magnetic property, paleoclimatic significance.

Assessment of coral bleaching using symbiotic zooxanthellae density and satellite remote sensing data in the Nansha Islands,South China sea

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chinese Science Bulletin 2011年第10期56卷 1031-1037页

作者： LI Shu,YU KeFu,CHEN TianRan,SHI Qi & ZHANG HuiLing cas key {2. of {3. sea geology,South China sea {3. of Oceanology,chinese academy of sciences.guangzhou 5103.1,China cas key {2. of {3. sea geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China

Coral bleaching,characterized by a significant loss of symbiotic zooxanthellae,is the primary cause of mass coral mortality and reef degradation throughout the *** characteristics,processes,and resistance of corals to bleaching varies significantly and is dependent on environmental *** documented a mass coral bleaching event in June 2.07 at the Meiji and Zhubi Reefs,Nansha Islands (NS),South China sea using ecological surveys and measurement of coral zooxanthellae density and sea surface temperatures (SST).More than 3. species of corals (between 0-2. m in depth) were *** bleached corals accounted for 15.6% of total corals in the investigated *** branching corals Pocillopora and Acropora were the most vulnerable species whereas the massive corals Porites and Favia were more tolerant of the high ***,we found no evidence of bleaching in Agariciidae corals suggesting that this family is resistant to thermal *** bleached corals had lost 72.-90% of their symbiotic ***,corals that had no visual signs of bleaching had also lost 3.%-53. of their zooxanthellae suggesting that most corals were experiencing the early stage of *** monthly mean SST during June 2.07 was 3..8°C,the highest since *** on measurements of SST and the Hotspots and DHW data (NOAA),we conclude that it the extremely high SSTs triggered this coral bleaching *** results suggest that the previously accepted temperature thresholds used to predict coral bleaching based on satellite data are likely to underestimate the extent and intensity of coral bleaching,at least in the NS.

关键词：珊瑚礁南沙群岛中国南海卫星遥感数据漂白黄藻密度共生

Ecological-sedimentary zonations and carbonate deposition,Xiaodonghai Reef Flat,Sanya,Hainan Island,China

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Science China Earth sciences 2011年第3期54卷 359-371页

作者： WANG Yue1,2. SHEN JianWei1 & LONG JiangPing3.1 Department of Marine geology, South China sea {2. of Oceanology cas key laboratory of {3. sea geology, South China sea {2. of Oceanology, chinese {12. of sciences. guangzhou 5103.1, China 2.Graduate University of chinese {12. of sciences. Beijing 100049, China 3.The Second Institution of Oceanography, State Oceanic Administration, Hangzhou 3.0012. China Department of Marine geology South China Sea Institute of Oceanology Guangzhou China Graduate University of chinese academy of {2. Beijing China cas key {2. of {3. sea geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China The Second Institution of Oceanography State Oceanic Administration Hangzhou China

Modern fringing reefs are developed on the intertidal to subtidal area of Xiaodonghai bay, Sanya, Hainan Island. The reef flat extends several dozen meters toward the sea. Various ecological and sedimentary zonations can be distinguished, including, from land to sea, beachrocks, large massive corals, inner reef flat, outer reef flat, and fore-reef slope. The carbonate sediments and constituent hermatypic coral communities are different in these zones. The beachrocks are composed mainly of biological sands, including coral skeletons, algae, gastropods, bivalves, and benthic foraminifera. Quartz sands are less common in this zone. Carbonate diagenesis in beachrocks is characterized by early cementation. The fringing reef flat is progradationally developed toward the sea. Large massive corals grew in the zone next to the beachrocks. These corals are large, flat-toped, and autochthonous in the production of bioclastic grains and lime mud. Large and massive coral skeletons are surrounded by coral skeletal grains, bioclasts, and lime-mud sediments. The inner reef flat consists mainly of skeletons of branching corals that are covered by bioclasts and lime mud, and living corals are mostly massive in form. Statistical analysis of coral-community dynamics shows that the outer reef flat with strong waves is the most suitable place for hermatypic corals to flourish. There, the living corals are most densely distributed. Both massive corals and branching corals (e.g., Acropora corymbosa) are exceptionally healthy in this zone. Bioclasts and lime mud are washed out due to strong wave action. Microbial carbonates generally are deposited within cavities of the beachrocks and coral skeletal cavities and on the surfaces of bioclastic grains. The latter two types, however, are more common. Ecological-sedimentary zonations across the Xiaodonghai reef flat from beachrocks to outer reef flat are controlled by variations in wave strength and water energy. Microbial carbonates rarely deve

关键词： microbial carbonates ecological-sedimentary zonation cementation reef flat Hainan Island

The fluxes and controlling factors of N_2. and CH_4 emissions from freshwater marsh in Northeast China

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Science China Earth sciences 2010年第5期53卷 700-709页

作者： YU JunBao1,2. LIU JingShuang2. SUN ZhiGao1, SUN WeiDong3. WANG JinDa2. WANG GuoPing2.& CHEN XiaoBing1 1 key Lab of Coastal Envionment Processed, Yantai institute of Coastal Zone Re{2.rch for Sustainable Development, chinese academy of {3. Yantai 2.4003. China 2.key Lab of Wetland Ecology and Environment, Northeast institute of Geography and Agricultural Ecology, chinese academy of {3. Changchun 13.012. China 3.key {12. of Isotope Geochronology and geochemistry, guangzhou institute of geochemistry, chinese academy of sciences. guangzhou 510640, China key Lab of Coastal Envionment Processed Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai China key Lab of Wetland Ecology and Environment Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun China key laboratory of Isotope Geochronology and {2. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Nitrous oxide (N2.) and methane (CH4) emissions were measured using a static chamber method in two adjacent plots of freshwater marsh predominated by Calamagrostis angustifolia, one is seasonal waterlogged (SW) and the other without surface water accumulation (NW), in Sanjiang Plain wetland (47°3.′N, 13.°3.′E), northeast China, during 2.02.2.04. The diurnal and seasonal flux variations of both gases were significantly correlated with 5-cm-soil temperature. The NW marsh is a source of N2. and sink of CH4, while the SW marsh is sink of N2. and source of CH4. Remarkably, we observed a N2. emission peak under Eh of +3.0 to +100 mV, and CH4 emission peak under Eh of +3.0 to +400 mV, which indicate additional sources of N2. and CH4 for the freeze-thaw induced emission peaks of N2. and CH4 observed between late July and early August. Further study shows that the additional N2. and CH4 were emitted under the frozen soil after thawing.

关键词： freeze-thaw region freshwater marsh methane nitrous oxide controlling factors

Identification and analysis of shear waves recorded by three-component OBSs in northeastern South China sea

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Progress in Natural Science:Materials International 2008年第2期18卷 181-188页

作者： Minghui Zhao ,Xuelin Qiu,Shaohong Xia,Ping Wang,Kanyuan Xia,Huilong Xu key laboratory of {2. {3. geology,South China {3. {3. of Oceanology,chinese academy of sciences.guangzhou 5103.1,China key laboratory of {2. {3. geology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China

Structure models associated with P-and S-wave velocities contain considerable amount of information on lithology and geophysical properties,which can be used to better understand the complexity of the deep crustal structure. However,records of converted shear waves are less due to the speciality of seismic survey at sea and the rigorous generated conditions. The study on shear waves has always been a weakness for studying the deep crustal structures of South China sea (SCS). In this paper,eleven three-component OBSs were deployed along the Profile OBS-2.01 in northeastern SCS. After the data processing of polarization and band-pass filter,converted S-wave phases were identified in the radical component records of nine OBSs. Taking the OBS7 as an example,identification and analysis of converted shear waves were presented and discussed in detail. A few phase groups,such as PwSc,PgSs,PnSc,PmS,and PwSn,were found coming from the deep crust or Moho interface by simple theoretical model calculation and ray-tracing simulation. The results not only provide the underlying basis for studies of S-wave velocity structure and Poisson’s ratio structure,but also reveal the relationship between crustal petrology and seismology,which will be of importance for making full use of S-wave information in the future.

关键词： Converted shear wave Deep crustal structure Three-component ocean bottom seismometer Northeastern South China sea

Total alkyl dibenzothiophenes content tracing the filling pathway of condensate reservoir in the Fushan Depression,South China sea

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Science China Earth sciences 2008年第S2期51卷 138-145页

作者： LI MeiJun1,WANG TieGuan1,LIU Ju2.ZHANG MeiZhu2.LU Hong3.MA QinLin2.& GAO LiHui2.1 State key laboratory of Petroleum Resources and Prospecting,Earth {2.and Geoinformatics School,China University of Petroleum,Beijing 102.49,China 2.Southern Oil Exploration and Development Company,PetroChina,guangzhou {3.,China 3.11},chinese {13. of {2.guangzhou 5102.0,China State key laboratory of Petroleum Resources and Prospecting Earth Sciences and Geoinformatics School China University of Petroleum Beijing China Southern Oil Exploration and Development Company PetroChina Guangzhou China guangzhou institute of {2. Chinese Academy of Sciences Guangzhou China

The condensates are generally characterized by high maturity,low concentration of steranes and ter-panes biomarkers and low content of non-hydrocarbon fraction. In this case commonly used steranes,terpanes and carbazoles parameters cannot be effectively applied in the reservoir-filling tracing. The hydrogen bond formed by sulfur atom in the dibenzothiophenes (DBTs) results in molecule adsorption and fractionation during oil migration in reservoir. Like carbazoles,total DBTs content decreases with the increasing of oil migration distance. Therefore,a new parameter——total DBTs content is proposed to be used to trace the oil migration orientation and filling pathway. In present study,total DBTs con-tents of condensates and light oils are obtained by adding internal standard——eight deuterium atoms substituted DBT during Gas Chromatography-Mass Spectrometry analysis of aromatic fraction. Except for a few samples with much lower content of non-hydrocarbon fraction,the total DBTs content shows a fine positive correlation with that of carbazoles. Large errors can be caused in the process of pyrrolic nitrogen compounds separation. The application of this new parameter in the Fushan Depression of Beibu Gulf Basin,South China sea indicates that this parameter is a reliable one to trace filling pathway in condensate reservoirs. Combined with other DBTs-related parameters,such as 4-/1-methydibenzo-thiophene and 2.4-/1,4-dimethyldibenzothiophene,oil migration orientation and filling pathway of the Fushan Depression was determined. The accumulations of Huachang oil field in the Fushan Depres-sion are mainly migrated and charged from northeast to southeast along the Huachang uplift. It can be predicated that the light oil and condensates in the Huachang oil field should be sourced from the source kitchen at the Bailian Sag. It shows that total DBTs content is an effective parameter to tracing oil migration orientation and filling pathway.

关键词： dibenzothiophene alkyl dibenzothiophene condensate reservoir filling pathway molecular markers the Fushan Depression

Petrology and mineral chemistry of new ureilites found in Grove Mountains, Antarctica

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Progress in Natural Science:Materials International 2008年第4期18卷 431-439页

作者： Bingkui Miaoa,b,, Yangting Linb, Guiqin Wangc, Daode Wangc, Ziyuan Ouyangd a key laboratory of Geological Engineering Center of Guangxi Province, Guilin University of Technology, Guilin 541004, China b State key laboratory of Lithospheric Evolution, institute of {3. and Geophysics, chinese academy of sciences. Beijing 10002., China c key laboratory of Isotope Geochronology and geochemistry,{12., chinese academy of sciences. guangzhou 510640, Chinad National Astronomical Observatories, chinese academy of sciences. Beijing 100012. China key laboratory of Geological Engineering Center of Guangxi Province Guilin University of Technology Guilin 541004 China State key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China key laboratory of Isotope Geochronology and {2. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Petrography and mineral chemistry of two new ureilites, GRV 02.512.and 02.93., from the Grove Mountains, Antarctica, are reported in this paper. GRV 02.512.exhibits a typical ureilite texture, and consists of 48.3. olivine, 9.4% pigeonite and 3..1% carbo- naceous interstitial material and/or reduction product. GRV 02.93. has a cataclastic porphyritic texture, and consists of 19.1% olivine and 14.1% pigeonite embedded in 66.3. carbonaceous interstitial material and/or reduction product. The coarse-grained olivine and pigeonite in both meteorites have homogeneous cores, and they are FeO-rich within the range of the ferroan subgroup (subgroup I) of olivine-pigeonite ureilites. All olivine grains of the meteorites show reduction zones along boundaries and cracks. Abundant diamond coexists with graphite as graphite-rich patches and veins in the carbonaceous interstitial material. Petrogenesis of both meteorites and the origin of diamond are discussed.

关键词： Meteorite Achondrite Ureilite Diamond Antarctica

Variation of the Fe/Mn ratio of ferromanganese crusts from the Central North Pacific: implication for paleoclimate changes

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Progress in Natural Science:Materials International 2005年第6期15卷 530-537页

作者： LU Zunli1**, LING Hongfei1*, ZHOU Feng1, JIANG Shaoyong1, CHEN Xiaoming1 and ZHOU Huaiyang2.1. State key laboratory for Mineral Deposits Re{2.rch, Department of Earth sciences. Nanjing University, Nanjing 2.0093. China 2. guangzhou institute of geochemistry,{3., China)Department of Earth & Environmental Science, University of Rochester State key laboratory for Mineral Deposits Re{2.rch Department of Earth Sciences Nanjing University Nanjing 210093 China guangzhou institute of {2. Chinese Academy of Sciences Guangzhou 510640 China

Contents of Fe, Mn and other elements in four ferromanganese crusts recovered from the central North Pacific are analyzed at high depth-resolution by electron microprobe for reconstructing factors controlling their deposition. Manganese (IV) in hydrogenetic ferromanganese crusts is mainly supplied as colloidal precipitates from the Oxygen Minimum Zone (OMZ), which concentrates high amounts of dissolved Mn (II). The iron is derived from carbonate dissolution and silicate particles of eolian dust. An increase in paleoproductivity during cooler climate would potentially lead to a decrease in Mn deposition due to enlargement of the OMZ which has a “temporary storage” effect for Mn. On the other hand, not affected by the OMZ, the iron entering the Fe-Mn crust would likely increase with the eolian dust input and surface productivity at glacial stages. As a result, the increasing Fe/Mn ratio should indicate a cooling climate. This is supported by the following observations. In the profile of the past 1 Ma, the variations of Fe/Mn ratio coincide with benthic oxygen isotope fluctuation in glacial-interglacial cycles. Three episodes with high Fe/Mn ratios, approximately at 2.6, 1.8 and 0.8 Ma, are detected within the past 3.Ma and coincide with major climate transitions and cooling events. The secular evolution pattern of Fe/Mn ratio in the Cenozoic is similar to the Pb isotope evolution which is mainly controlled by eolian dust and related to climate. The Fe/Mn evolution pattern is also broadly consistent with the global deep-sea oxygen isotope records. Therefore, Fe/Mn ratio recorded in the ferromanganese crusts may be a new proxy for climate change.

关键词： Fe/Mn ratio ferromanganese crust central North Pacific paleoclimate.