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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 {2. of Marine Geology, Tongji University, Shanghai 2.0092. china 2. the key laboratory of submarine geoscience, state oceanic administration, hangzhou 310012. china state key {2. of Marine Geology Tongji University Shanghai china The key laboratory of {2. geoscience state oceanic administration hangzhou china

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.

Size fractionated biomass and productivity of phytoplankton and new production in the Prydz Bay and the adjacent Indian sector of the Southern Ocean during the austral summer 1998/1999

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Acta Oceanologica Sinica 2003年第4期22卷 651-670页

作者： Cai Yuming 1,3, Ning Xiuren 1,2.3, Zhu Genghai3, Shi Junxian3 1. key Laborary of submarine {2.s of state oceanic administration,hangzhou 310012.china. 2. key Laborary of Ocean Dynamic Processes and Satellite Oceanography of state oceanic administration,hangzhou 310012.china 3. Second Institute of Oceanography of state oceanic administration, hangzhou 310012.china key Lab submarine Geosci {2. Ocean Adm Hangzhou 310012 Peoples R China key Lab Ocean Dynam Proc Satellite Oceanog State Ocean Adm Hangzhou 310012 Peoples R China Inst Oceanog state Ocean Adm 2 Hangzhou 310012 Peoples R China

The paper deals with the studies on the cell abundance, the composition of dominant species, size fractionated biomass and productivity of phytoplankton, new production, the environmentally restricted mechanism in the Prydz Bay and the adjacent Indian sector of the Southern Ocean during the austral summer 1998/1999. The results showed that there was marked feature of spatial zonation in the sea areas investigated. In the Prydz Bay and its adjacent continental shelf, the biomass and productivity of phytoplankton were high; those of continental slope and open ocean area were obviously low. The nutrient concentration had opposite distribution trend, due to the consumption of phytoplankton. It mainly affected by the vertical stability of water column, grazing pressure of zooplankton, temperature and light etc. The results of size-fractionation showed that the average contribution of netplankton to total chlorophyll a in studied sea areas was 52.2.%, those of nano- and picoplankton were 2..4 % and 18.4 %, respectively. The average contribution of netplankton to total primary production was 52.4 %, those of nano- and picoplankton were 2..7 % and 18.9 %, separately. It is same as previous conclusion that the contribution of picoplankton to productivity is slightly larger than that to biomass of phytoplankton communities. The average new production and f-ratio were 2.0.6 mg/ (m(2.)d) and 0.43, respectively.

关键词： phytoplankton standing stock primary productivity size-fractionation new production the Southern Ocean

High-resolution dating of Co-rich crusts: A comparative study using the methods of orbital pacing and ^(2.0)Th_(ex)/^(2.2.Th dating

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Science china Earth Sciences 2009年第4期52卷 484-488页

作者： HAN XiQiu1,2. QIU ZhongYan1,2.3, MA WeiLin1,2.& QIAN JiangChu1,2.1 key laboratory of {2. geosciences, state oceanic administration, hangzhou 310012. china 2.Second Institute of Oceanography, state oceanic administration, hangzhou 310012. china 3 Department of Earth Sciences, Zhejiang University, hangzhou 31002., china key laboratory of {2. geosciences State Oceanic Administration Hangzhou 310012 China Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China Department of Earth Sciences Zhejiang University Hangzhou

Due to their slow growth rates, seamount Co-rich crusts are very difficult to date with high resolution and precision. This paper is to test the use of orbital pacing on the growth profile of crusts to determine high-resolution age and growth rate. Crust CB14 from the central Pacific Ocean was selected for this study. We first examined the growth pattern in detail under a reflected-light microscope and ascertained that the growth environment was stable for the sub-layer 1 (0-3 mm). We then used electron micro-probe line-scanning to obtain elemental profiles. The pattern of the power spectrum analysis of the Al-profile revealed that there are significant cycles of 113.9, 87.8, 51.5, 42.2.and 2..8 μm. These cycles correspond to the Milankovitch cycles of 53.1, 41, 2., 19.7 and 12.ka, respectively, and yield the growth rate of about 2.14 mm/Ma and an age of about 1.40 Ma for the boundary between the sub-layer 1 and sub-layer 2. We also used a drilling machine with a numerically controlled drive to obtain high-resolution samples at 0.1mm intervals, and used the 2.0Thex/2.2.h method to date the samples. For the uppermost 1.3 mm, the growth rate was about 2.15 mm/Ma, and the age for the layer at the depth of 3 mm was about 1.40 Ma, which coincides perfectly with the results obtained from orbital pacing. Thus, it is considered that orbital pacing is a new and effective method to determine the growth rate of the seamount Co-rich crust. This method is applicable for establishing a high-resolution age frame for the crusts of the world's oceans.

关键词： seamount Co-rich crust Milankovitch cycles 2.0Thex/2.2.h dating growth rates of Mn-crusts central Pacific Ocean

Variation of reactivity of particulate and sedimentary organic matter along the Zhujiang River Estuary

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Acta Oceanologica Sinica 2003年第4期22卷 557-568页

作者： Chen Jianfang 1,2. Jin Haiyan 1,2. Yin Kedong3, Li Yan 1,2.1. key laboratory of {2. geosciences of state oceanic administration, hangzhou 310012. china. 2. laboratory of Regional Oceanography, Second Institute of Oceanography, state oceanic Aedministration, hangzhou,310012. china 3. Department of Biology, Hong Kong University of Science and Technology, Hong Kong Kay Lab submarine Geosci state Ocean Adm Hangzhou 310012 Peoples R China state Ocean Adm Inst Oceanog 2 Lab Reg Oceanog Hangzhou 310012 Peoples R China Hong Kong Univ Sci & Technol Dept Biol Hong Kong Hong Kong Peoples R China

To investigate organic matter source and reactivity in the Zhujiang River (Pearl River) Estuary and its adjacent areas, particulate organic carbon (POC), particulate hydrolysable amino acids (PHAA), and Chl a during two cruises in July 1999 and July 2.00 were measured. The highest POC and PHAA concentration was observed in the waters with maximum Chl a. The spectra distribution, relative content (dry weight in milligram per gram), PHAA-C% POC and other indicators such as the ratios of amino acids vs. amino sugars (AA/AS) and glucosamine vs. galactosamine (Glum/Gal) suggested that particulate amino acids in the water column and sediments in the Zhujiang River Estuary were mainly derived from biogenic processes rather than transported from terrestrial erosion. In inner estuary where high turbidity was often observable, organic matter was mainly contributed by re-suspension of bottom sediments with revealed zooplankton, microbial reworked characteristics, which suggest that these organic matters were relatively 'old'. In the estuarine brackish region, organic matter in water column is mainly contributed by relatively fresh, easily degradable phytoplankton derived organic matter. During physical - biological processes within the eastuary, organic matter derived from phytoplankton was subjected to alteration by zooplankton grazing and bacterial reworking.

关键词： organic matter reactivity amino acids the Zhujiang River Estuary

On tectonic movement in the South china Sea during the Cenozoic

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Acta Oceanologica Sinica 2009年第1期28卷 25-36页

作者： LIN Changsong CHU Fengyou GAO Jinyao TAN Yonghua key laboratory of {2. geosciences of state oceanic administration Second Institute Oceanography State Oceanic Administration Hangzhou 310012 China Second institute of Oeeanography State Oceanic Administration Hangzhou 310012 China

The tectonic movement taking place at the end of Cretaceous and the beginning of Cenozoic had opened the Cenozoic phase of polycyclic tectonic movements,then the whole crust of the South china Sea had been mainly subjected to the regional stress field of tectonic tension,which was characterized by rifting *** times of regional tectonic movement and sedimentation had been assembled into a geological development history of polycyclic ***,the tectonic movements were strongly intensified at the end of Cretacious and the beginning of Paleagene,between Late Eocene and Mid-Oligocene,during Mid-and Late *** three times of tectonic movement had built the most important regional tectonic interfaces in the South china *** movements of the South china Sea were the result and epitome of interaction of the Eurasia,Pacific and Indo-Australia plates,that is,they were introduced by polycyclic changes of directions,rates and strengths of lithospheric movements and asthenospheric flows across the Pacific and Indo-Australia plates.

关键词： South china Sea Cenozoic tectonic movement

Siliceous microplankton fluxes and seasonal variations in the central South china Sea during 1993-1995: monsoon climate and ? Nino responses

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Chinese Science Bulletin 2000年第23期45卷 2168-2172页

作者： WANG Rujian, LIN Jun, ZHENG Lianfu, CHEN Ronghua & CHEN Jianfanglaboratory of Marine Geology of MOE, Tongji University, Shanghai 2.0092. china The {2. laboratory of submarine geoscience, state oceanic administration, hangzhou 310012. china Correspondence should be addressed to Wang Rujian laboratory of Marine Geology of MOE Tongji University Shanghai China The key laboratory of {2. geoscience State Oceanic Administration Hangzhou China

Seasonal variations of radiolarian and diatom fluxes in the central South china Sea during 1993-1995 were overwhelmingly controlled by monsoon climate. Radiolarian and diatom increased obviously during the Northeast (from November to February) and Southwest (from June to September) monsoons and decreased during the periods between the monsoons. The change of circulation driven by the monsoons improved water exchange in the different areas that brought rich nutrient materials for the surface microplankton, thereby enhancing radiolarian and diatom fluxes. Variation of radiolarian flux coincided with organic carbon flux, surface primary and export productivities. High radiolarian flux corresponded to high surface primary productivity. Radiolarian and diatom fluxes raised abnormally during 1994-1995 could be attributed to the El Nino event during the period.

关键词： siliceous microplankton fluxes seasonal variations monsoon climate El Nino event central South china Sea.

Geochronology, Geochemistry and Its Tectonic Significance of Chahe Granites in Hainan Island

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Journal of Earth Science 2013年第4期24卷 619-625页

作者：唐立梅陈汉林董传万初凤友 key laboratory of {2. geosciences Second Institute of OceanographyState Oceanic Administration Department of Earth Sciences Zhejiang University

There are very few studies on the granites formed in Late Permian in Hainan （海南） Island. Petrology, geochronology and geochemistry research on Late Permian granites in Chahe （叉河） area, Hainan Island will be reported in this article. The results show that, Chahe granites formed in 2.1 Ma, are riched in SiO2. alkali, Fe2.3 while depleted in MgO and CaO, with low Sr and high Yb, and have all the features consistent with A-type granite. The forming of Chahe granites may suggest that Hainan Island was already in post-orogenic setting in Late Permian.

关键词： granite U-Pb age dating geochemistry Hainan Island.

Faulting, magmatism and crustal oceanization of the Okinawa Trough

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Acta Oceanologica Sinica 2009年第3期28卷 40-49页

作者： GAO Jinyao ZHANG Tao FANG Yinxia YANG Chuanguo MEI Sai key laboratory of {2. geosciences of state oceanic administration Hangzhou 310012 China Second Institute of Oceanography State Oceanic Administration Hangzhou 310012 China

The paper focuses on the characteristics of faulting and magmatism of the Okinawa Trough and the relation between them. En-echelon grabens are ranked oblique to the continental shelf edge uplift, and the Longwang uplift, the rifting block ridge in the northern segment and the ＂Mianhua uplift＂ in the southern segment have possibly preserved characteristics of volcanism and magmatism occurring with those rifting phases. The clockwise rotation of the southern Ryukyu Islands, driven by collision between Luzon and Taiwan, has played a key role in the crustal oceanization, enhancing the crustal extension of the southern segment and inducing volcanic magmatism in those grabens, among which the Yaeyama graben is a typical example of the presence of oceanic crust. Faulting and magmatism were mainly migrating towards the island arc asymmetrically. The crustal oceanization of the Okinawa Trough is difficultly interpreted by the linear magnetic anomaly model, which is fit for the symmetric spreading of the mid-oceanic ridges.

关键词： Okinawa Trough fault graben uplift oceanic crust volcanic magma

The chemical distribution characteristics of variant form phosphorus in the seawater of the South china Sea

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Acta Oceanologica Sinica 2003年第3期22卷 385-394页

作者： Jianming Pan, Chuanyu Hu, Jianfang Chen, Xiaoya Liu, Huaiyang Zhou, Weidong Ji key laboratory of {2. geosciences of state oceanic administration, Second Institute of Oceanography, state O-ceanic administration, hangzhou 310012.china. E-mail:panjianming@sio. zj.edu. cnThird Institute of Oceanography, state oceanic administration, Xiamen 361005,china state Ocean Adm Inst Oceanog 2 Key Lab Submarine Geosci Hangzhou 310012 Peoples R China state Ocean Adm Inst Oceanog 3 Xiamen 361005 Peoples R China

According to two cruises investigation information in summer and winter during 1998 and 1999, the phosphorous concentration distribution and changes of summer and winter were discussed primarily in the South china Sea. The results show that the phosphate concentration of surface seawater in summer is distinctly lower than that in winter, averaging 0.04 mumol/dm(3) in summer and 0.35 mumol/ dm(3) in winter. The organic phosphorous concentration of surface seawater in summer is higher than that in winter, averaging 0.12.mumol/dm(3) in summer and 0. 04 mumol/dm(3) in winter respectively. The seasonal changes of total phosphorus are similar to phosphate, averaging 0.2. mumol/dm(3) in summer and 0.61 mumol/dm(3) in winter respectively. In vertical direction, phosphate, TDP and TP content are the lowest in upper 50 m water column, and increase in linearity rapidly with water depth, increasing slowly under 500 m, reach to maximum about 1000 m, then decrease slightly with water depth increasing. The vertical distribution is typical in summer, and there is small dispersed for phosphorus concentration for the same depth of different stations. However, in winter there is a large disperse for phosphate, TDP and TP, specifically for phosphate at 2.0 m at which the concentration is maximum. This result indicates that there are large differences in hydrology and biology conditions that affect largely the chemical environment of the South china Sea. The organic phosphorus is the predominant in surface seawater of the South china Sea, but the inorganic phosphorus is the predominant in layers below depth of 150 m. The organic phosphorus concentration in deep water usually decreases with water depth increasing. The organic phosphorus in summer is remarkably more than that in winter because of the strong biology activities in summer.

关键词： the South china Sea specific form phosphorus biogeochemistry processes

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 {2. geosciences of state oceanic administration, hangzhou 310012. china 2. laboratory of Marine Geology, Tongji University, Shanghai 2.0092. china 3. Institute of Estuarine and Coastal Research, East china Normal University, Shanghai 2.0062. china key Lab submarine Geosci {2. Ocean Adm Hangzhou 310012 Peoples R China Tongji Univ Lab Marine Geol Shanghai 200092 Peoples R China E china Normal Univ Inst Estuarine & Coastal Res Shanghai 200062 Peoples R 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)