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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 geology, MEO,{3., shanghai 2.0092. china laboratory of marine geology 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

Calcium carbonate pump during Quaternary glacial cycles in the South china Sea

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Chinese Science Bulletin 2003年第17期48卷 1862-1869页

作者： LIU Zhifei, XU Jian, TIAN Jun & WANG Pinxian laboratory of marine geology,{3., shanghai 2.0092. china laboratory of marine geology Tongji University

The preservation and dissolution of calcium carbonate (namely calcium carbonate pump) controls the pH of seawater in global oceans by its buffer effect, and in turn plays a significant role in global changes in atmospheric CO2 concentration. The results from measured carbonate con-tents over the past 2 Ma at ODP Site 1143.in the South china Sea provide high-resolution records to explore the process of the calcium carbonate pump during Quaternary glacial cy-cles. The results indicate statistically that the highest car-bonate accumulation rate leads the lightest d 18O by about 3.6 ka at transitions from glacials to interglacials, and that the strongest carbonate dissolution lags the lightest d 18O by about 5.6 ka at transitions from interglacials to glacials. The calcium carbonate pump releases CO2 to the atmosphere at the glacial-interglacial transitions, but transports atmos-pheric CO2 to deep sea at the interglacial-glacial transitions. The adjustable function of the calcium carbonate pump for the deep-sea 23.O- concentration directly controls parts of global changes in atmospheric CO2, and contributes the global carbon cycle system during the Quaternary.

关键词：中国南海碳酸钙第四纪冰川旋回海洋钻探图古气候

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 geology,{3., shanghai 2.0092. china 2. Geological and Paleontological Institute, university of Kiel, 24118 Kiel, Germany 3. Department of geology, Northwest Unive laboratory of marine geology 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.

The Upper Devonian orbital cyclostratigraphy and numerical dating conodont zones from Guangxi,South china

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Science china Earth Sciences 2005年第1期48卷 32-41页

作者： GONG Yiming, XU Ran, TANG Zhongdao & LI Baohua Faculty of Earth Science, china university of Geosciences, Wuhan 43.074, china {3. of marine geology, tongji university, shanghai 2.0092. china 1. Faculty of Earth Science China University of Geosciences 430074 Wuhan China 2. laboratory of marine geology Tongji University 200092 Shanghai China

The hierarchically organized laminae, bundles, bundlesets and superbundlesets which correspond to a sub-Milankovitch, obliquity or precession, eccentricity and long eccentricity cyclothems, respectively, have been distinguished from the Upper Devonian Fras-nian-Famennian (F-F) transitional carbonate successions deposited in the carbonate-basin and slope facies of Guangxi, South china. The durations of cyclothems are 8000-10000a, 16667a or 3.3.3., 100000a and 400000a, respectively. The ratio of eccentricity to precession, eccentricity to obliquity, and long eccentricity to eccentricity is 1 : 6, 1 : 3.and 1 : 4 in the Devonian, respectively. Orbital cyclostratigraphical studies show that the durations of the conodont falsio-valis Zone, transitans Zone, punctate Zone, Lower hassi Zone, Upper hassi Zone, jamieae Zone, Lower rhenana Zone, Upper rhenana Zone, linguiformis Zone, Lower triangularis Zone, Middle triangularis Zone and Upper triangularis Zone are 0.4, 0.4, 0.4, 0.3. 0.4, 0.2, 0.8, 0.6, 0.8, 0.3. 0.3.and 0.3.Ma from bottom to top, respectively, and the duration of the Frasnian is 4.3.Ma. The conodont is the normal marine organism of the latest mass extinction (the latest linguiformis Zone) and the first recovery (including the whole Lower triangularis and Middle triangularis Zone) in the F-F transition. The conodont mass extinction and recovery lasted 200000-100000a and 0.6 Ma, respectively. We consider that average durations of the fossil zones calculated by reported numerical ages divided by fossil zone numbers within a stage or series or system cannot discovery complications and non-uniformity of evolutionary organisms and environments.

关键词： orbital cyclostratigraphy, conodont zone, numerical dating, mass extinction, Devonian, Guangxi, South china.

Postglacial sea-level changes and development stages of fluvial-estuarine system

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Acta Oceanologica Sinica 1993年第4期12卷 573-584页

作者： Li Congxian Department of marine geology and Geophysics, tongji university,{3. Dept. of marine geology & Geophysics Tongji Univ. Shanghai 200092 China

-On the basis of the data obtained from the investigations on some rivers in china and Australia, the author discusses the spatial and temporal changes of various portions of fluvial-estuarine system during postglacial sea-level rising in present coastal and deltaic areas. The evolution of a fluvial-estuarine system can be divided into four development stages: early transgression, late transgression, stationary and regression. Early transgression brought about filling-in of the paleo-valley formed in low stand of sea level. In response to late transgression the estuaries were created, during the stationary stage the big swamp was developed. The regression led to estuaries to be filled with sediments and then became deltas. At the same locality the fluvial-estuarine system changed with time. In the transgressive period the lower reach of a river changed into an estuary, and then became nearshore area. In the regressive period the nearshore area changed into an estuary , and then became delta.

关键词： Sea-level fluvial-estuarine system postglacial period paleo-valley paleo-interfluve retrogressive aggrada-tion

Paleobiogeography of Ostracoda and Foraminifera in the china sea area

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Acta Oceanologica Sinica 1991年第1期10卷 93-105页

作者： Wang Pinxian and Zhao Quanhong Department of marine geology, tongji university, {3., 2.0092. china Dept marine geology Tongji Univ Shanghai 200092 China China

The distribution of ostracods and benthonic foraminifers in the china sea area is briefly reviewed from the paleobio-geographic viewpoint in this paper. Three regions can be distinguished in the area on the basis of modern distribution data: Region I (the Huanghai Sea and the Bohai Sea) with cool and temperate forms, Region I (the East china Sea and the northern part of the South china Sea) with subtropical warm-water forms and Region Ⅲ (central and southern parts of the South china Sea) with larger foraminifers and other tropical warm-water forms. The occurrence of Nummulites-Discocyclira fauna in the Eocene deposits of the East china Sea indicates a northward extension of tropical zoogeographical region at the time, whereas the distribution pattern of the Miocene Nephrolepidina-Miogypsiua-Austrotrillina fauna in the South china Sea resembles that of the present larger-foraminiferal fauna. In the South china Sea and Taiwan, a warm-water fauna with Asterorotalia and Pseudorotalia first appeared in late Miocene and then flourished in the Pliocene. Its northward invasion into the Bohai Sea area during late Pleistocene may be related to changes in current system. Many of the endemic foraminiferal and ostracod genera and species ( Sinocytheridea etc. ) in recent coastal faunas probably have originated from the South china Sea, and their occurrence in Japan or Australia may be indicative of ties between these areas during glacial times.

关键词： Paleobiogeography of Ostracoda and Foraminifera in the china sea area

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 geology of the Ministry of Education,{3., shanghai 2.0092. china 2. State Key laboratory of Estuarine and Coastal Research, East china Normal university, shanghai 200062, china 3. shanghai Museum, shanghai 200003. china Key laboratory of marine geology 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

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 laboratory,{3., shanghai 2.0092. china 2. First Institute of Oceanography, State Oceanic Administration of china, Qingdao 266003. china 3. Guangzhou Institute of marine geology laboratory 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.

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 43.074, china 2. Institute of Resources & Environments, Henan Polytechnic university, Jiaozuo 454003. china 3. Department of Computer Science, South-Central university for Nationalities, Wuhan 43.074, china 4. laboratory of marine geology, tongji university, shanghai 2.0092. china Faculty of Earth Science and State Key laboratory of Geological Processes and Mineral Resources china university of Geosciences Wuhan china Institute of Resources & Environments Henan Polytechnic university Jiaozuo china Department of Computer Science South-Central university for Nationalities Wuhan china laboratory of marine geology{3. shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.43.(‰ V-PDB) to +3.54 (‰ V-PDB) and from ?29.3. (‰ V-PDB) to ?24.14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3.X 15%)) values from 0.015 to 0.144, TOC values from 0.02% to 0.21%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.20 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.