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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 laboratory of Marginal Sea {2.,South china Sea institute of Oceanology,chinese academy of sciences Guangzhou 510301,china CAS key laboratory of Marginal Sea {2. 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 35 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 31%-53% of their zooxanthellae suggesting that most corals were experiencing the early stage of *** monthly mean SST during June 2.07 was 30.8°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

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沉积物中甲烷水合物资源评价的理论模型分析及地质意义

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天然气工业 2003年第3期23卷 24-28页

作者：吴保祥雷怀彦中国科学院兰州地质研究所气体地球化学国家重点实验室

如何能够准确评价沉积物中甲烷水合物的资源量是目前油气界研究的热点问题。本文以达西定律为基础 ,通过理论模型对水合物稳定区、沉积区的深度分布进行了量化并对各自的边界条件的影响因素做了详细的分析。同时对大概的水合物沉积时间... 详细信息

如何能够准确评价沉积物中甲烷水合物的资源量是目前油气界研究的热点问题。本文以达西定律为基础 ,通过理论模型对水合物稳定区、沉积区的深度分布进行了量化并对各自的边界条件的影响因素做了详细的分析。同时对大概的水合物沉积时间范围和沉积分布特征的量化进行了确定。这些结果表明了自然界中水合物的分布边界很大程度上与海底甲烷通量、热能通量、水深和沉积物中流体通量有关 ,甲烷水合物沉积区厚度会到达并保持一个临界恒定值。水合物的聚集时间和分布特征与不同的扩散体系有关。因此在进行甲烷水合物的资源评价当中 ,了解并确定上述一些参数是解决资源评价过程的非常重要的一个环节。

关键词：沉积物甲烷水合物资源评价理论模型地质意义通量

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An unusual isotopic fractionation of boron in synthetic calcium carbonate precipitated from seawater and saline water

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Science china Chemistry 2006年第5期49卷 454-465页

作者： XIAO Yingkai1,2.LI Shizhen1,WEI Haizhen1,SUN Aide1,ZHOU Weijian2.& LIU Weiguo2.1. Qinghai institute of Salt Lakes,chinese {2. of sciences,Xining 810008,china 2. State key laboratory of Loess and Quaternary geology,institute of Earth Environment,chinese {2. of sciences,Xi’an 710075,china 1. Qinghai institute of Salt Lakes Chinese Academy of Sciences Xining 810008 China 2. State key laboratory of Loess and Quaternary {2. Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

Inorganic calcium carbonate precipitation from natural seawater and salinewater at various pH values was carried out experimentally. The results show the clear positiverelationships between boron concentration and δ^(11)B of inorganic calcium carbonate with the pH ofnatural seawater and saline water. However, the variations of boron isotopic fractionation betweeninorganic calcite and seawater/saline water with pH are inconsistent with the hypothesis thatB(OH)_4^- is the dominant species incorporated into the biogenic calcite structure. The isotopicfractionation factors a between synthetic calcium carbonate precipitate and parent solutionsincrease systematically as pH increases, from 0.9884 at pH 7.60 to 1.0072.at pH 8.60 for seawaterand from 0.982. at pH 7.60 to 1.0178 at pH 8.75 for saline water. An unusual boron isotopicfractionation factor of larger than 1 in synthetic calcium carbonate precipitated fromseawater/saline water at higher pH is observed, which implies that a substantial amount of theisotopically heavier B(OH)_3 species must be incorporated preferentially into synthetic inorganiccarbonate. The results propose that the incorporation of B(OH)_3 is attributed to the formation ofMg(OH)_2.at higher pH of calcifying microenvironment during the synthetic calcium carbonateprecipitation. The preliminary experiment of Mg(OH)_2.precipitated from artificial seawater showsthat heavier ^(11)B is enriched in Mg(OH)_2.precipitation, which suggests that isotopically heavierB(OH)_3 species incorporated preferentially into Mg(OH)_2.precipitation. This result cannot beapplied to explain the boron isotopic fractionation of marine bio-carbonate because of thepossibility that the unusual environment in this study appears in formation of marine bio-carbonateis infinitesimal. We, however, must pay more attention to this phenomenon observed in this study,which accidentally appears in especially natural environment.

关键词： boron, isotopic fractionation, calcium carbonate precipitate, seawater, saline water.

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The high-resolution climate recorded in the δ^(18)O of Porites lutea from the Nansha Islands of china

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chinese Science Bulletin 2001年第24期46卷 2097-2102页

作者： YU Kefu, CHEN Tegu, HUANG Dingcheng, ZHAO Huanting, ZHONG Jinliang & LIU Dongsheng (LIU Tungsheng)South china Sea institute of Oceanoiogy,{2.. Guangzhou 510301, china:geology and geophysics institute.{2., Beijing 10002., china South china Sea institute of Oceanology Chinese Academy of Sciences Guangzhou China geology and geophysics {2. Chinese Academy of Sciences Beijing China

A Porites lutea core from Yongshu Reef of Nansha Islands covering 50 years growth history was ana-ly/ed for oxygen isotopic composition with monthly and seasonally resolution. The calibration of the δ18O with the instrumental temperature indicated that the coral δ18O is a good indicator for sea surface temperature (SST) and air temperature (t). It can be used to reconstruct the SST and air temperature of the Yongshu Reef sea area. In addition, the coral δ18O provides signatures for the intensity of the East Asia monsoon and it is a record for the activities of El Nino events. With the calibrated SST and air temperature formulas, the most recent fifty years SST and air temperature were reconstructed based on the coral δ18O, thus back up the understanding of the climate of Nansha Islands to 1950. far beyond the limit of the instrumental recording since September 1988. It was found that, in general, increasing 1℃ air temperature results in 0.2.‰decrease in skeletal δ18O.

关键词： Nansha Islands Porites lutea δ18O sea surface tem-perature East Asia monsoon.

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Dinosaur eggs and dinosaur egg-bearing deposits(Upper Cretaceous) of Henan Province,china:Occurrences,palaeoenvironments,taphonomy and preservation

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Progress in Natural Science:Materials International 2009年第11期19卷 1587-1601页

作者： Xinquan Liang~(a,*),Shunv Wen~(a,b),Dongsheng Yang~a,Shiquan Zhou~c,Shichong Wu~d a key laboratory of Isotope Geochronology and {2.,Guangzhou institute of {2.,chinese academy of sciences, Guangzhou 510640,china b Graduate School of the chinese academy of sciences,Beijing 100039,china c First geology and Exploration institute,Henan Bureau of geology,Mineral Exploration and Development Supervision,Nanyang 473003,china d Zhuzhou institute of Mineral Resources and Geological Survey,Hunan Geological Survey,Zhuzhou 412.07,china [a]key laboratory of Isotope Geochronology and {2. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China [b]Graduate School of the chinese academy of sciences Beijing 100039 China [c]First geology and Exploration institute Henan Bureau of Geology Mineral Exploration and Development Supervision Nanyang 473003 China [d]Zhuzhou institute of Mineral Resources and Geological Survey Hunan Geological Survey Zhuzhou 412007 China

The Upper Cretaceous dinosaur egg-bearing deposits in Henan Province,central china are divided into three formations in ascending order:Gaogou,Majiacun and *** Gaogou Formation belongs to alluvial fan deposits containing the fossil dinosaur egg assemblage of Faveoloolithus,Dendroolithus,Dictyoolithus,Paraspheroolithus and *** Majiacun Formation is interpreted as braided stream to meandering stream deposits with assemblage of Ovaloolithus,Paraspheroolithus,Placoolithus,Dendroolithus,Prismatoolithus, rare Youngoolithus and *** Sigou Formation is shallow lacustrine/palustrine to low-sinuosity river sedimentary rocks with assemblage of Macroolithus,Elongatoolithus,Ovaloolithus and Paraspheroolithus. To date,37 oospecies,13 oogenera and 8 oofamilies of dinosaur eggs have been *** dinosaur eggs are preserved in the floodplain deposits,whereas allochthonous and parautochthonous dinosaur eggs are preserved in the alluvial *** suggests that river floodplains are the best environments for the preservation of numerous autochthonous dinosaur *** preservation of most dinosaur eggs in brown to red calcic palaeosoils,muddy siltstones or mudstones suggests that the paleoclimate of the nesting area was *** presence of gray and green mudstone and coal layers,however,indicates that there existed an ephemeral subhumid climate during the middle and Late *** is suggested that such a climate was favorable for the development of meandering streams in a vegetated environment.

关键词： Dinosaur eggs Upper Cretaceous Fluvial deposit Characteristics of taphonomy and preservation Henan Central china

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Ultramafic xenoliths in Mesozoic diorite in west Shandong Province

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Science china Earth sciences 2004年第6期47卷 489-499页

作者： CHEN Lihui1,2.& ZHOU Xinhua2.1.The key laboratory of Orogenic Belts and Crustal Evolution,Ministry of Education,{2. and School of Earth and Space sciences,Peking University,Beijing 100871,{2. 2.institute of geology and geophysics,chinese academy of sciences,Beijing 10002.,{2. Correspondence should be addressed to Chen Lihui(email: lihui_chen@***) 1. The key laboratory of Orogenic Belts and Crustal Evolution Ministry of Education China and School of Earth and Space Science Peking University 100871 Beijing China 2. institute of geology and geophysics Chinese Academy of Sciences 100029 Beijing China

Ultramafic xenoliths are common in Tietonggou intrusion, Laiwu, Shandong Prov-ince. Peridotite xenoliths develop two-stage metasomatism popularly: (i) The early metasoma-tism is characterized by intergranular clinopyroxene and phlogopite; (ii) The later metasomatism is characterized by orthopyroxene veins with a few plagioclases and amphiboles. These ul-tramafic xenoliths are thought to be mostly from the crust-mantle transitional zone on the basis of their combination, mineral chemistry, equilibrium temperature, and metasomatic characteristics. Major elements, rare earth elements, and Sr-Nd isotopic composition of the ultramafic xenoliths indicate that there is a petrogenetic relationship between the silica-enriched xenoliths and their host diorites. We propose that such silica enrichment might be an indicator of melt-rock interac-tions in the Mesozoic lithosphere beneath western Shandong.

关键词： ultramafic xenoliths, crust-mantle transitional zone,metasomatism, Tietonggou intrusion, Laiwu.

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Variations of sulfur and carbon isotopes in seawater during the Doushantuo stage in late Neoproterozoic

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chinese Science Bulletin 2003年第13期48卷 1375-1380页

作者： ZHANG Tonggang, CHU Xuelei, ZHANG Qirui, FENG Lianjun & HUO Weiguo key Lab of Mineral Resources Exploration and Research, institute of geology and geophysics,{2., Beijing 10002., china key Lab of Mineral Resources Exploration and Research Institute of Geology and Geophysics Chinese Academy of Sciences China

Successive analyses of sulfur and carbon isotopic compositions of carbonates strata in the Doushantuo Formation in the Yangtze area were accomplished through a method of extracting trace sulfate from carbonates. Sulfur and carbon isotopic compositions of coeval seawater were estimated from the samples that show the least diagenetic alteration. A high-resolution age curve of sulfur isotopes in seawater sulfates was obtained in the Doushantuo stage, which reflects the trend of variation in seawater sulfur isotopes after the Neoproterozoic snowball Earth event. Similar characteristics of variation in carbon isotopes were observed in the coeval carbonates. A large positive d 34S excursion over +2.?occurs in ancient seawater sulfates in the early Doushantuo stage. Simultaneously, the d 13C values in ancient seawater carbonates exhibit a positive excursion up to 10. The maximum d 34S and d 13C values are +46.4 and +6.9? respectively. In the middle Doushantuo stage, the range of variation in d 34S values of seawater is relatively narrow, but d 13C values are quite high. Then, d 34S values of seawater become oscillating, and the same occurs in d 13C values. Negative excursions in d 34S and d 13C values occur simultaneously at the end of the Doushantuo stage, and the minimum d 34S and d 13C values dropped down to -10.1 and -5.7? respectively. The characteristics of variations in the sulfur and carbon isotopes of ancient seawater imply strong changes in oceanic environment that became beneficial to inhabitation and propagation of organism. The organic productivity and burial rate of organic carbon once reached a quite high level during the Doushantuo stage. However, the state of environment became unstable after the global glaciation. The global climate and environment possibly were fluctuating and reiterating. The negative excursions in d 34S and d 13C values occurring at the end of the Doushantuo stage may represent a global event, which might be related to oxidation of dee

关键词：硫碳同位素分馏新元古代成岩作用

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Spatial variations of tidal water level and their impact on the exposure patterns of tidal land on the central Jiangsu coast

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Acta Oceanologica Sinica 2010年第1期29卷 79-87页

作者： WANG Zhenyan GAO Shu HUANG Haijun key laboratory of Marine {2. and Environment Chinese Academy of Sciences Qingdao 266071 China Graduate School Chinese Academy of Sciences Beijing 100039 China MOE key laboratory for Coast and Island Development Nanjing University Nanjing 210093China

The exposed area of intertidal zone varies with tidal water level changes, If intercomparisons of satellite images are adopted as a method to determine geomorphological changes of the intertidal zone in response to accretion or erosion processes, then the effect of water level variations must be evaluated. In this study, two Landsat TM images overpassing the central Jiangsu coastal waters on 2.January and 7 March 2.02. respectively, were treated by the changing detection analysis using Image Differencing and Post-classification Comparison. The simultaneous tide level data from four tide gauge stations along the coast were used for displaying the spatial variations of water levels and determining the elevations of waterlines. The results show that the spatial variations of water levels are highly significant in the central Jiangsu coastal waters. The huge differences of tidal land exposure patterns between the two imaging times are related mainly to the spatial variations of tidal water levels, which are controlled by the differences in tidal phases for different imaging times and the spatial variations of water level over the study area at each imaging time. Under complex tidal conditions, e.g., those of the central Jiangsu coastal waters, the tide-surge model should be used to eliminate effectively the effects of water level variations on remote sensing interpretation of geomorphological changes in the intertidal zone.

关键词： waterline water level variations exposure patterns central Jiangsu coast remote sensing

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Anatexis in Himalayan crust:Evidence from geochemical and chronological investigations of Higher Himalayan Crystallines

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Science china Earth sciences 2005年第9期48卷 1347-1356页

作者： YANG Xiaosong1, JIN Zhenmin2.& MA Jin1 1. State key laboratory of Earthquake Dynamics, {2. of geology, china Earthquake Administration, Beijing 10002., china 2. Faculty of Earth sciences, china University of Geosciences, Wuhan 430074, china 1. State key laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration 100029 Beijing China 2. Faculty of Earth sciences China University of Geosciences 430074 Wuhan China

Migmatization in Higher Himalayan Crystallines (HHC) results from anatexis. The widely distributed migmatites in HHC are an important clue to investigate the relationship be- tween anatexis and the origins of Higher Himalayan leucogranites (HHL), and to understand the effect of anatexis on crustal evolution during the post-collision period. We studied in detail the chemical features of three basic constituent parts of the migmatites, i.e. leucosome, mesosome and melanosome, and determined the K-Ar ages of leucosomes. Our studies indicate that type-I leucosome is the product of crystallization of melt generated by partial melting of mesosome at source region, but type-II leucosome and HHL probably underwent crystallization differentiation of plagioclase during melt aggregation and migration. The age of 2..67 Ma of Type-I leucosome, which is a little older than the beginning of MCT movement, indicates that anatexis may have played an important role in the formation of MCT. That the ages of type-II leucosome (ranging from 14.82.to 18.37 Ma) are consistent with that of HHL provides new chronological evidence for the relationship between migmatization and HHL. We obtained a very young age of 6.2. Ma of Type-II leucosome that provides new time constraint on magma activity in the central segment of Higher Himalayas.

关键词： Higher Himalayan Crystallines, migmatite, anatexis, leucosome, K-Ar age.

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Distribution of molluscan remains in the sediment of the Chukchi Sea and its vicinity, the Arctic

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Acta Oceanologica Sinica 2003年第4期22卷 607-619页

作者： Gao Aiguo 1,2. Xu Fengshan3, Sun Haiqing 1,2. Li Lon1 1. First institute of Oceanography, State Oceanic Administration, Qingdao 2.6061,china. 2. {2. laboratory of Marine Sedimentology and Environmental geology, State Oceanic Administration, Qingdao 2.6061,china 3. institute of Oceanology, chinese academy of sciences, Qingdao 2.6071,china State Ocean Adm Inst Oceanog 1 Qingdao 266061 Peoples R China State Ocean Adm Key Lab Marine Sedimentol & Environm Geol Qingdao 266061 Peoples R China chinese Acad Sci Inst Oceanol Qingdao 266071 Peoples R China

The result of an analysis of mollusca remains collected from the Chukchi Sea, Beaufort Sea and Bering Sea in the First chinese National Arctic Research Expedition, from July to September, 1999 is presented. Seventeen species of mollusca have been identified, which belong to two classes: Bivalvia and gastropoda. The compositions of the mollusca are very simple. According to the distribution pattern two groups may be distinguished among molluscan species. The Pan-Arctic and circumboreal group comprises Nuculana pernula, ***, Nucula bellotii, Astarte montagui, Seripes groenlandicus, Macoma calcarea, M. moesta alaskana, Liocyrna fluctuosa, Mya pseudoarenaria and Turritella polaris. Three species, Cyclocardia crebricostata, Trichotrois coronata and Argobuccinum oregonense are components of the Pan-Arctic and Pacific boreal group. With regard to feeding habits, detritus feeders dominate. There are 7 species of detritus feeders, i.e., Nuculana pernula, N. radiata, Nucula bellotii, Macoma calcarea, M. moesta alaskana, Macoma sp. and Trichotropis coronata. Detritus feeders are dominant with regard to the numbers of species as well as to the frequency of occurrence. Macoma calcarea is the most abundant species.

关键词： Chukchi Sea Beaufort Sea Bering Sea molluscan remains

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