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Cycladophora davisiana(Radiolarian)in the Bering Sea during the late Quaternary:A stratigraphic tool and proxy of the glacial Subarctic Pacific Intermediate Water

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Science China Earth Sciences 2005年第10期48卷 1698-1707页

作者： WANG Rujian1 & CHEN Ronghua2.1. State Key laboratory of marine {2., tongji university, shanghai 2.0092. China 2. The Key laboratory of Submarine Geoscience, State Oceanic Administration, Hangzhou 310012. China tongji university State Oceanic Administration

Cycladophora davisiana (Radiolarian) contents are counted in two cores of the Ber-ing Sea and correlated well with the oxygen isotopic records of ice in the deep core obtained by the Greenland Ice Sheet Project II (GISP 2. and deep-sea sediments (SPECMAP) of the world oceans. Millennial scale climatic events, for example, Younge Dryas and B?lling/Aller?d events, Heinrich1 and Dansgaard-Oeschger1events, recorded by C. davisiana percents are distin-guished from Core B4-2. C. davisiana events b, c1, c2. d, e1 and e2. respectively, corresponding to oxygen isotopic 2.0, 3.1, 3.3, 4.0, 5.1 and 5.3, are identified from Core B2.9. High resolution re-cords of C. davisian are tuned to the oxygen isotopic records in GISP 2.and SPECMAP and the depth-age frameworks are established in the two cores, supplying a stratigraphic base for future paleoceanographic and paleoclimatic studies. High C. davisiana during the glacial periods in the two cores indicate that they can serve as a proxy of the glacial Subarctic Pacific Intermediate Water, which verifies the glacial Subarctic Pacific Intermediate Water brought from the Bering Sea.

关键词： Cycladophora davisiana, stratigraphic tool, YD and B/A events, Heinrich 1 and D/O1 events, proxy of glacial Subarctic Pacific Intermediate Water, late Quaternary, Bering Sea.

Determination of tectonic background for sedimentary basin from sandstone geochemistry

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Chinese Science Bulletin 1998年第14期43卷 1191-1196页

作者： SHAO Lei 1, K. Stattegger 2.and LI Wenhou 3 1. laboratory of marine {2., tongji university, shanghai 2.0092. China 2. Geological and Paleontological Institute, university of Kiel, 2.118 Kiel, Germany 3. Department of {2., Northwest Unive laboratory of marine {2. Tongji University Shanghai China Geological and Paleontological Institute University of Kiel Kiel Germany Department of geology Northwest University Xi’an China

The chemical composition of sedimentary rocks is mainly controlled by source rocks. Through examining chemical composition of terrigenous rocks, the tectonic evolution of a sedimentary basin can be modeled. The Turpan Basin belongs to a continental sedimentary basin and its source rocks are derived from the upper continental crust.

关键词： sedimentary rock geochemistry basin analysis Turpan Basin.

Relationship between magnetic fabric parameters and dynamic characteristics of deposits in different environments

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Chinese Science Bulletin 1998年第22期43卷 1917-1921页

作者： CHEN Qingqiang 1,3 , LI Congxian\+1 and CONG Youzi\+2.1. marine geology {2., tongji university, shanghai 2.0092. China 2. First Institute of Oceanography, State Oceanic Administration of China, Qingdao 2.6003, China 3. Guangzhou Institute of marine geology {2. Tongji University Shanghai China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China First Institute of Oceanography State Oceanic Administration of China Qingdao China

Comparison of magnetic fabric parameters of deposits in different modern sedimentary environments indicates that values of \%P, F\% and \%L\% of eolian deposits are lower obviously than those of hydrogenic ones respectively. On relationship diagrams of magnetic fabric parameters, data points of eolian samples concentrated in limited area near origin of coordinates indicate that dynamic intensity is lower with less variation; while those of hydrogenic ones depart from origin of coordinates suggest higher intensity of sedimentary dynamics. Analyses of dynamic characteristics of different sedimentary environments indicate that values of magnetic fabric parameters of deposits are determined by dynamic types and characteristics of depositional processes. Magnetic fabric analyses of deposits are effective in determination of sedimentary environments.

关键词： magnetic fabric parameters sedimentary environment transporting medium.

Development of ancestors' cultivation revealed in phytolith assemblages from Guangfulin relics

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Chinese Science Bulletin 2003年第3期48卷 287-290页

作者： ZHANG Yulan1,2. ZHANG Minbin1 & SONG Jian3 1. Key laboratory of marine {2. of the Ministry of Education, tongji university, shanghai 2.0092. China 2. State Key laboratory of Estuarine and Coastal Research, East China Normal university, shanghai 2.0062. China 3. shanghai Museum, shanghai 2.0003, China Key laboratory of marine {2. of the Ministry of Education Tongji University Shanghai 200092 China State Key laboratory of Estuarine and Coastal Research East China Normal University Shanghai 200062 China shanghai Museum Shanghai 200003 China

shanghai Museum has got great achievements in re-excavating Guangfulin relics. It is the first time that the cultural remains of Wangyoufang type is found above the Liangzhu cultural remains which comes from East Henan Province, providing previous materials for researching cul-ture evolution around Taihu Lake. Samples were taken from the immature soil layer and cultural layers of Guangfulin relics for phytolith analysis. According to the systemic re-search for the archaeological remains and phytolith fossil, the phytoliths in Guangfulin relics can be divided into four zones. The development of rice agriculture and living condi-tion of Guangfulin ancestors was discussed based on the ex-isting rice fan-shaped phytolith, rice shell phytolith, diatom fossil and archaeology evidence in the same layer. The Guangfulin relics has gradually developed since a high sea level 5000 years ago, and the broad rice agriculture has si-multaneously developed. The newly re-excavated relics pro-vides valuable materials for the research of ancestors and ancient culture in shanghai.

关键词：上海 Guangfulin遗址远古农作物植物化石

Impact of the closure of Indonesian seaway on climate: A numerical modeling study

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Chinese Science Bulletin 2003年第S2期48卷 88-93页

作者： YU Yongqiang, ZHOU Zuyi & ZHANG Xuehong 1. LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 10002., China: 2. laboratory of marine geology, tongji university, {2. 2.0092.China Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100029 Peoples R China tongji Univ Lab Marine Geol Shanghai 200092 Peoples R China

Using a global OGCM and its relevant coupledocean-atmosphere GCM with the contemporary, 6 MaBPand 14 MaBP oceanic topography, respectively, a series ofnumerical experiments are implemented in order to investi-gate the effect of the north shift of Australian continent onthe tropical oceanic circulation, especially the formation ofthe western Pacific warm pool. The numerical experimentsof the individual OGCM forced by the modern atmosphericcirculation indicate that the closure of Indonesian passageresults in warming in the tropical Pacific Ocean and coolingin the tropical Indian Ocean; furthermore, it also results inchange in source of the Indonesian Through Flow (ITF) wa-ter, e.g. ITF mainly originates from the south Pacific at 14MaBP, but it mainly originates from the north Pacific *** coupled model shows similar results as the individualOGCM qualitatively.

关键词： Indonesian Through Flow (ITF) Western Pacific Warm Pool Australian Plate Paleo-oceanography.

Microfossils, carbonate lysocline and compensation depth in surface sediments of the northeastern South China Sea

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Acta Oceanologica Sinica 2003年第4期22卷 597-606页

作者： Chen Ronghua1, Xu Jian2. Meng Yi3, Wang Dongjun1 Liu Chuanlian2. Huang Baoqi2. Zhang Fuyuan1 1. Key laboratory of Submarine Geosciences of State Oceanic Administration, Hangzhou 310012. China {2., tongji university, shanghai 2.0092. China 3. Institute of Estuarine and Coastal Research, East China Normal university, shanghai 2.0062. China Key Lab. of Submarine Geosci. State Hangzhou 310012 China laboratory of marine {2. Tongji University Shanghai 200092 China Institute of Estuarine/Coastal Res. East China Normal University Shanghai 200062 China

Based on the quantitative analyses of abundance of planktonic foraminifera, benthic foraminifera, calcareous nannofossils, the ratios of calcareous to siliceous microfossils, and the determination of carbonate contents in the surface sediments of the northeastern South China Sea, it has been found that the carbonate contents, the abundance of planktonic foraminifera and calcareous nannoplankton, and the ratio of calcareous microfossils decrease rapidly while the ratio of the benthic foraminifera to the total foraminiferal fauna, specific value of siliceous microfossils, and the percentage of the agglutinated tests in the benthic foraminiferal fauna increase with the water depth. The results indicate that the microfossils abundance and ratio, and the carbonate content are closely related to the carbonate lysocline and carbonate compensation depth (CCD) in the study area. In addition, the carbonate lysocline and the CCD are different between the southern and northern parts of the South China Sea. Both the lysocline and the CCD are deeper in the south with 2.600 and 3 600 m than in the north with 2.2.0 and 3 400 m, respectively.

关键词： microfossils carbonate lysocline depth carbonate compensation depth (CCD) surface sediments South China Sea (SCS)

Quaternary high-resolution opal record and its paleoproductivity implication at ODP Site 1143,southern South China Sea

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Chinese Science Bulletin 2003年第4期48卷 363-367页

作者： WANG Rujian & LI Jian laboratory of marine {2., MEO, tongji university, shanghai 2.0092. China laboratory of marine {2. MEO Tongji University Shanghai 200092 China

The correlation of opal content and MAR with oxygen isotopic records of benthonic foraminifera at Site 1143, southern South China Sea indicates that, since about 900 ka, the increasing opal content and MAR during the interglacial periods is inferred to reflect the higher surface productivity, for the intensified summer monsoon during the interglacial periods would result in the enhanced upwelling and nutrient supply. Time-sequence spectral analyses of oxygen isotopic record, opal content and MAR at intervals of 0900 ka reveal that the changes of surface productivity were dominantly forced by the variations of the earth orbital cycles.

关键词：中国南海第四纪蛋白石含量 MAR 古生产力四膜虫沉积物氧同位素

A multi-layer model for early diagenesis

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Chinese Science Bulletin 1997年第16期42卷 1385-1387页

作者： MEI HongmingDepartment of marine geology,{2., shanghai 2.0092. China Department of marine geology Tongji University Shanghai China

EARLY diagenesis is defined here as a series of physical, chemical and biological reactions operating between depositional particles, porewaters and environmental water medium in the processes of deposition and shallow burial. Early diagenesis can produce geochemical succession within deposits, which can be divided from top to bottom into oxidation zone (OX), sulphate reduction zone (SR) and methanogenesis zone (ME). Part of the reaction

关键词： early diagenesis biogeochemical zone multi-layer model.

Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science China Earth Sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2. XU Ran1, TANG Zhongdao1, SI Yuanlan3 & LI Baohua4 1. Faculty of Earth Science and State Key laboratory of Geological Processes and Mineral Resources, China university of Geosciences, Wuhan 430074, China 2. Institute of Resources & Environments, Henan Polytechnic university, Jiaozuo 454003, China 3. Department of Computer Science, South-Central university for Nationalities, Wuhan 430074, China 4. laboratory of marine geology, tongji university, shanghai 2.0092. China China university of Geosciences Henan Polytechnic university South-Central university for Nationalities tongji university

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13Ccarb and δ 13Ckerogen) from +0.43 (‰ V-PDB) to +3.54 (‰ V-PDB) and from ?2..38 (‰ V-PDB) to ?2..14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2.3 X 15%)) values from 0.015 to 0.144, TOC values from 0.02. to 0.2.%, V/Cr values from 0.3 to 2.0, Sr/Ba values from 3.2. to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South China, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2. climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South China.