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Distribution characteristics of magnetic susceptibility of the surface sediments in the southern Yellow Sea

Chinese Science Bulletin 2003年第B06期48卷 37-41页

作者： ge shulan~(1.2,3),{1., first institute of oceanography, state oceanic administration. qingdao 2.6061. china 2. institute of geology and geophysics, Chinese Academy of Sciences, Beijing 1.0029. china 3. Graduate School. Chinese Academy of Sciences, Beijing 1.0039. china 1. key {1. of marine sedimentology and environmental geology First Institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. institute of {1. and geophysics Chinese Academy of Sciences 100029 Beijing China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China

The characteristic distributions of magnetic susceptibility (MS) are analyzed on the basis of susceptibility of 1.2 surface sediment samples in the southern Yellow Sea (SYS). The preliminary results are as follows: first, the distributions clearly correspond to different modern sediment assembla{1.s in the continental sea, which indicates different sediment origins. With the 30 μCGS isoline being taken as demarcation line, the study area can then be divided into section H (high MS value area) and section L (low MS value area). Section H is mainly adjacent to land with two main sources of the Changjiang River and the Huanghe *** L is mainly an eddy sediment area, where Yellow Sea Cold Water is entrenched all the year round. The distribution pattern of MS could tell apart strong or weak hydrodynamic conditions and has a close relation to the circulation system in this area. At the areas of the SYS Circumfluent and northern East china Sea (NECS) Circumfluent (weak hydrodynamic), the MS has low values, while in the areas of Coastal Current (strong hydrodynamic), the values are *** the same time, the oxidizing areas tend to take on higher MS, while the reducing areas have lower one. It seems safe to say that the MS in the continental sea reflects more of the sediment origin and sedimentary environment, which is different from that of loess, lake and surface soil as a climate proxy.

关键词：中国黄海表面沉积物磁化率等值线长江黄河旋涡沉积区循环系统

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Organic carbon and nitrogen isotopes in surface sediments from the western Arctic Ocean and their implications for sedimentary environments

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Acta Oceanologica Sinica 2006年第5期25卷 39-54页

作者： CHEN Zhihua shi {1. CAI Deling han yibing YANG Zuosheng Ocean University of china Qingdao 266003 China first {1. of oceanography State Oceanic Administration Qingdao 266061 China key {1. of marine sedimentology ＆ environmental geology of state oceanic administration First Institute of Oceano-graph State Oceanic AdministrationQingdao 266061 China

Surface sediments from the Chukchi Sea and adjacent arctic deep sea were investigated for organic carbon and nitrogen isotopes （in δ1.Corg and δ1.Norg） as well as biogeni＇c silica （BSiO2）. δ1.Corg and δ1.Norg values of surface sediments in the study area fall between the end-member values of marine and terrestrial organic matter from the surrounding lands and seas, their variations reflect the changes of marine productivity and terrestrial supply in the study area. BSiO2 shows a similar distribution pattern with δ1.Corg and δ1.Norg, and can be used as an indicator of marine productivity. In the central-west Chukchi Sea and the Chukchi Rise, sediments have higher δ1.Corg, δ1.Norg and BSiO2 values, indicating the region has high marine productivity influenced by the nutrient-rich branches of the Pacific waters. In the coastal zone off northwestern Alaska, δ1.Corg and δ1.Norg values become lighter, indicating a weakening marine productivity and an increasing terrigenous supply due to the effects of the least nutrient-rich branch of the Pacific waters. In the north and the northeast of the study area （including the Chukchi Plateau, the Canada Basin and the Beaufort shelf）, δ1.Corg, δ1.Norg and BSiO2 have the lowest values, and the terrigenous organic matter becomes dominant in surface sediments because this region has the longest ice-covered duration, the least nutrient-rich seawater and the increasing supply of terrestrial materials from the Mackenzie River and the northern Alaska under the action of the clockwise Beaufort gyre. Because the subarctic Pacific waters are continuously discharged into the central basin of the Arctic Ocean through the study area, the nutrient pool in the Chukchi Sea can be considered as a typical open system, the ratio of δ1.Norg to BSiO2 content show some tracers that the level of nutrient utilization is contrary to nutrient supply and marine productivity formed in seawater.

关键词： western Arctic Ocean surface sediments organic carbon and nitrogen isotopes biogenic silica

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Rock magnetic property of gravity core CSH1.from the northern Okinawa Trough and the effect of early diagenesis

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Acta Oceanologica Sinica 2007年第5期26卷 54-65页

作者： ge {1. shi xuefa WU Yonghua LEE Tehquei XIONG Yingqian SAITO Yoshiki marine Sedimentation and {1. geology key laboratory of state oceanic administration First Institute of Oceanography State Oceanic Administration Qingdao 266061 China institute of {1. and geophysics Chinese Academy of Sciences Beijing 100029 China institute of Earth Sciences Taipei China geology Survey of Japan Tsukuba 306 - 8567 Japan

Detailed rock magnetic investigations were undertaken at 2 -4 cm interval for the gravity core Cshi （with a length of 1..36 m） from the northern Okinawa Trough. Time-scale of the core was constructed by two characteristic tephras and foraminferal assembla{1.s, indicating an a{1. of 50 ka for the bottom of the core. Except for three tephras and abrupt decrease in surface, there are little chan{1.s in all kinds of rock magnetic parameters that can be correlated to the climate chan{1. for the last 50 ka. Different from the common sediments, most S-ratios （S equals the negative ratio of IRM-0.3T to SIRM, which is an indicator of low coercivity content） of the sediments are smaller than 0. 9, which implies a substantial amount of magnetic minerals with high coercivity. The existence of iron sulphide （ greigite or pyrrhotite） is revealed by representative susceptibility - temperature curves showing 200 350 ℃ Curie temperature in addition to 580 ℃ of magnetite, and also by awful smell during heating and dark heating products. Both the occurrence of authi{1.nic iron sulphide and quick decrease of magnetic parameters near the surface clearly show that sediments from Core Cshi have undergone early dia{1.nesis. The featureless magnetic chan{1.s of the whole core except for three tephras mean that the post-depositonal alteration is so strong that most original signals have been destroyed. For the same reason, the organic matter in sediment and sulphate in pore water must have been consumed along with dissolution, precipitation of iron and manganese happening sequencially during the redox reaction series. Great caution must be taken when using these altered chemical parameters for the interpretation of climatic chan{1.s.

关键词： northern Okinawa Trough gravity core of Cshi rock magnetic property characteristic tephra early diagenesis

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Identification of the thick-layer greigite in sediments of the South Yellow Sea and its geological significances

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Chinese Science Bulletin 2014年第22期59卷 2764-2775页

作者： Jianxing Liu xuefa {1. shulan ge Qingsong Liu Zhengquan Yao Gang Yang Paleomagnetism and geochronology {1. (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences key {1. of marine Sedimentation and environmental geology First Institute of Oceanography State Oceanic Administration

Magnetic minerals in sediments of the continental shelf are sensitive to environmental ***,to determine the exact phases of magnetic minerals is the prerequisite to investigate the paleoenvironmental *** this study,a comprehensive rock magnetic investigation,coupled with mineralogical studies,was carried out on the long core NHH01.with a length of 1.5.64 m)from the central continental shelf of the South Yellow ***-domain greigite was identified as the dominant magnetic carrier in sediments between44.90 and 51.80 m,and terrigenous magnetite is the major magnetic phase in the adjacent *** existence of greigite unambiguously indicates an anoxic *** tentatively interpreted that such an environment could be formed by the fast sea level changes,long-existing of the cold eddies during warm stages,or in a lake which might be related to locally tectonic ***,the occurrence of the thick-layer greigite could supply a new perspective to paleoenvironmental or even tectonic studies.

关键词：南黄海中部沉积物地质意义古环境意义识别厚层环境变化磁性矿物

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Magnetostratigraphy of borehole EY02-2 in the southern Yellow Sea and its paleoenvironmental significance

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Chinese Science Bulletin 2006年第7期51卷 855-865页

作者： ge {1. shi xuefa ZHU Rixiang LIU Yanguang YIN Ping LIU Lejun key Lab of {1. Sedimentation and environmental geology First Institute of Oceanography State Oceanic Administration Qingdao 266061 China institute of {1. and geophysics Chinese Acadelny of Sciences Beijing 100029 China

Detailed rock magnetic and paleomag- netic studies have been undertaken on borehole EY02-2 (70m in length) in the southern Yellow Sea (SYS). The main Curie point revealed by magnetic susceptibility-temperature (k-T) curve is 580―600℃ indicating magnetite dominance. The hysteresis loop parameters show large variation of magnetic minera size in different sedimentary contexts: it is larger in subtidal sediment than in terrigenous sediment and even larger than in shallow sea sediment. This trend is correlative with distance to sediment source and dynamic strength. Magnetostratigraphic results show that the M/B polarity boundary (MBPB) is at 63.29m and there are at least 7 polarity transitions (Nr1.7) in Brunhes chron that can be tentatively correlated with 6 named polarity reversals. Three positive polarity reversals occur in late Matuyama chron and the early two may be the record of Kamikatsura happening in 886±3 kaB.P. Magnetic susceptibility (MS) and sediment grain size behave so differently in some sedimentary facies that certain big environmenta changes can be clearly revealed. generally, the MS and grain size of subtidal and terrigenous sediments are larger than shallow sea sediments and MS value around 1.×1.?5SI and mean grain size of 7Φ seems to be indicators of shallow sea sediments of deep water depth. However, the frequently used excellen climatic proxies such as MS and grain size in loess and deep sea sediments fail to record such climatic cycles revealed by oxygen isotope in continental seaThe various sediment sources, sedimentation dy- namic and their complex changes between glacial and interglacial periods should be the cause of fail- ure.

关键词：磁地层学钻井黄海岩石磁性 M/B极性边界磁化率

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Benthic foraminiferal δ^(1.)C minimum events in the southeastern Okhotsk Sea over the last 1.0 ka

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Chinese Science Bulletin 2014年第15期59卷 3066-3074页

作者： Yonghua Wu xuefa {1. Jianjun Zou Zhenbo Cheng Kunshan Wang shulan ge Fengdeng {1. state {1. laboratory of marine geology Tongji University key {1. of marine sedimentology and environmental geology First Institute of Oceanography State Oceanic Administration

A total of six d1.C minimum events,i.e.,VI,V,IV,III,II,and I,were observed via a stable carbon and oxygen isotope analysis of infaunal benthic foraminifera Uvigerina *** gravity core OS03-1.in the southeastern Okhotsk Sea over the last 1.0 *** events occurred at1.2–1.9,1.2–90,85–76,57–54,44–40,and 1.–1. ka *** largest negative excursions reached 2.5%in event V and were greater than 1.in the other *** proposed that all d1.C minimum events were caused by the increase in sea surface water productivity,the weakened formation of Okhotsk Sea intermediate water,and the enhancement of the oxygen minimum *** negative excursions were unaffected by methane hydrate destabilization and subsequent methane release based on the results obtained by using archaeal lipid markers.

关键词：鄂霍次克海底栖有孔虫东南部事件氧同位素分析甲烷水合物甲烷释放分解释放

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Status and Trends of Biological Invasions in china

Status and Trends of Biological Invasions in China

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第三届全国生物入侵大会

作者： Hui Ding~1,Hai-gen Xu~(1*),Sheng Qiang~2,Ling Meng~2,Zheng-min han~3,Jin-lai Miao~4,Bai-shi Hu~2, Hong-ying Sun~5,Jian-ying Guo~6,Cheng Huang~7,Jun-cheng Lei~1,Zhi-fang Le~1 1.The state key environmental Protection laboratory of Biosafety,Nanjing institute of environmental Sciences under Ministry of environmental Protection,Nanjing 210042 2.Nanjing Agricultural University,Nanjing 210095 3.Nanjing Forestry University,Nanjing 210037 4.The first institute of oceanography,state oceanic administration.qingdao 2.6061.5.Nanjing Normal University,Nanjing 210046 6.institute of Plant Protection,Chinese Academy of Agricultural Sciences,Beijing 100193 7.Nanjing University,Nanjing 210093

Using document survey,filed survey and expert consultation,the invasive alien species(IAS) in the terrestrial ecosystem,inland water ecosystem and marine ecosystem of {1. were investigated. 488 IAS whose information include name,taxonomy,distribution,origin,site and time firstly identified, pathway,damage,nutrient circumstance,and habitant were *** those IAS,species of Plantae,Animalia,Fungi,Vira,Procaryotae,Protista were 266,1.0,26,1.,1.,3 respectively,and these species accounted for 54.51.,34.84%,5.33%,2.46%,2.25%,0.61.respectively.392 IAS were analyzed on their invading *** results showed,occurrence of 31.IAS before 1.50,the number of IAS newly identified increasing totally after 1.50,209 IAS account for 53.32%after *** where IAS were firstly identified mainly distributed in the coastal region,Yunnan Province and Xinjiang Uyghur Autonomous Region,but trend of northward shift of sites was *** unintentional introduction was primary invasion pathway recently,the percentage of intentional introduction almost equaled to of unintentional ***,Europe and Asia were main origins of IAS of *** number of IAS decreased from coastal region towards inland gradually.

关键词： Biological,Invasions Invasive alien species,Distribution,Drigin,china

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Identification of the thick-layer greigite in sediments of the South Yellow Sea and its geological significances

Identification of the thick-layer greigite in sediments of t...

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中国科学院地质与地球物理研究所201.年度（第1.届）学术年会

作者： Jianxing Liu xuefa {1. shulan ge Qingsong Liu Zhengquan Yao Gang Yang Paleomagnetism and geochronology {1. (SKL-LE) Institute of Geology and GeophysicsChinese Academy of Sciences University of Chinese Academy of Sciences key {1. of marine Sedimentation and environmental geology First Institute of OceanographyState Oceanic Administration

Magnetic minerals in sediments of the continental shelf are sensitive to environmental ***, to determine the exact phases of magnetic minerals is the prerequisite to investigate the paleoenvironmental significances. In this study, a comprehensive rock magnetic investigation, coupled with mineralogical studies, was carried out on the long core NHH01.with a length of 1.5.64 m) from the central continental shelf of the South Yellow Sea. Single-domain greigite was identified as the dominant magnetic carrier in sediments between44.90 and 51.80 m, and terrigenous magnetite is the major magnetic phase in the adjacent layers. The existence of greigite unambiguously indicates an anoxic *** tentatively interpreted that such an environment could be formed by the fast sea level changes, long-existing of the cold eddies during warm stages, or in a lake which might be related to locally tectonic uplifting. Therefore, the occurrence of the thick-layer greigite could supply a new perspective to paleoenvironmental or even tectonic studies.

关键词： Rock magnetism Greigite Continental shelf environment South Yellow Sea

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