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Sample records for bohai bay basin

  1. Structures of the Bohai Petroliferous Area, Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    This paper, for the first time, deals with a more systematic study of the structures in the Bohai petroliferous area that covers nearly one third of the Bohai Bay basin. The study mainly involves the effects of pre-existing basement faults on the basin formation, the characteristics of basin geometry and kinetics, the modelling of the tectonic-thermal history, the polycyclicity and heterogeneity in the structural evolution and the natural seismic tomographic images of the crust and upper mantle. The authors analyze the features of the dynamic evolution of the basin in the paper and point out that the basin in the Bohai petroliferous area is an extensional pull-apart basin.

  2. Prospect of Oil/Gas Exploration in Beach Area of Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    Li Gansheng; Dou Lirong; Yuan Lingling; Rong Jiashu

    1997-01-01

    @@ Introduction Located in beach zone along Bohai Bay, the beach area of Bohai Bay basin is restricted between coastline and water depth of 5 m, stretching from Bayuquan to Huludao, Liaoning Province and Qinhuangdao, Hebei Province to Weihekou, Shandong Province.

  3. Tectonic Characteristics and Evolution of Bohai Bay Basin, China

    Institute of Scientific and Technical Information of China (English)

    LIU Pengju; ZHANG Meisheng; SUN Xiaomeng; YANG Baojun

    2002-01-01

    Synthetical analyzing the deep geophysical data within Bohai bay basin the authors detect the deep crustal structure presenting high geothermal flux, thinned crust and arched Moho discontinuity, and the basin basement belongs to rigid continental crust. The development of the basin was controlled by two - dimensional faults in NNE and NWW directions. The tectonic units of the basin can be subdivided into three structural divisions: the east, middle and west division. The basin is considered as a continental rift. The tectonic background and regional right - lateral stress field during the late Cretaceous and Paleogene were a compound result of the Kula Plate W - directional subducting under Eurasia Continental Plate in 80 ~ 74Ma and the Philippine sea Plate W -directional subducting under the Eurasia Continental Plate since 60Ma, the long-rang effect of the India Continental Plate wedging into the Eurasia Continental Plate and of the Siberia Plate SE - directional relatively moving.

  4. Comparison between control factors of high quality continental reservoirs in Bohai Bay basin and Ordos basin

    Institute of Scientific and Technical Information of China (English)

    Junmao ZHENG; Jun YOU; Dongbo HE

    2008-01-01

    Bohai Bay basin,a typical extensional rift basin,and Ordos basin,an intra-craton down-warped basin,represent two important basin types in China.Because of their respective features,the main control factors for their high quality reservoirs are different.In Bohai Bay basin,the sandbody shows great variety in types and severely separated distribution and its high quality reservoirs are mostly controlled by the vertical secondary pore and vertical abnormal pressure.On the other hand,the sandbody in Ordos basin features a relative lack of variety,good continuity,indistinct vertical zone,and its reservoirs are mainly controlled bY the diagenetic differentiation caused by different sedimentation inside the sandbody.Therefore,in the Bohai Bay basin,the exploration should be based on the analysis of sedimentary facies and the favorable diagenefic zones and formations.The focus in Ordos basin,however,should be put on the relatively high permeability sandstones in a generally low permeable sandstone background.

  5. Fluid Dynamic Field in Bozhong Depression, Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The data from regional geology, boreholes, geophysics and tests are integrated to analyze the fluid dynamic field in the Bozhong depression, Bohai Bay basin. The current geothermal gradient is determined to be about 2.95 ℃/100 m by integrating 266 drill-stem test (DST) measurements and comparing with the global average value. The paleogeothermal gradients are calculated from the homogenization temperatures of saline inclusions, which vary both laterally and vertically. The data from sonic logs, well tests and seismic velocities are used to investigate the pressure variations in the study area. The mudstone compaction is classified as three major types: normal compaction and normal pressure, under-compaction and overpressure, and past-compaction and under-overpressure. The current pressure profile is characterized by normal pressure, slight pressure and intense overpressure from top to bottom. The faults, unconformity surfaces and interconnecting pores constitute a complex network of vertical and horizontal fluid flows within the depression. The fluid potential energy profiles present a “double-deck” structure. The depocenters are the area of fluids supply, whereas the slopes and uplifts are the main areas of fluids charge.

  6. Cenozoic tectonic evolution of the Bohai Bay Basin and its coupling relationship with Pacific Plate subduction

    Science.gov (United States)

    Liang, Jintong; Wang, Hongliang; Bai, Ying; Ji, Xinyuan; Duo, Xuemei

    2016-09-01

    The Bohai Bay Basin is a Mesozoic-Cenozoic rift basin in eastern China. Based mainly on a balanced-section analysis, this study compares the spatio-temporal differences of tectonic evolution in relation to strike-slip faults among different depressions within the basin. In combination with the analysis of subsidence characteristics, the study also attempts to clarify the Cenozoic tectonic evolution of the basin and its coupling relationship with the subduction of the Pacific Plate. It was found that: (1) the strike-slip faults were activated generally from south to north and from west to east during the Cenozoic; (2) there is a negative correlation between the intensity of tectonic activity in the Bohai Bay Basin and subduction rate of the Pacific Plate; and (3) the migration direction of the basin depocenters is consistent with the direction of Pacific Plate subduction.

  7. Geologic Features of the Petroleum-rich Sags in the Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    NIU Jiayu; ZHAO Wenzhi; ZOU Caineng; JIANG Lingzhi

    2008-01-01

    More than 40 years have been passed since exploration and development of oil-gas began in the Bohai Bay Basin. Though we have faced with many difficulties during our exploration, exciting discoveries in petroleum-rich sags have been made in recent years. Studies show that the petroleumrich sags are characterized by multiple sets of oil-gas accumulation in the pre-Eogene to Neogene strata in profile and large-area connection or superimposition of oil-gas reservoirs in different strata. Therefore, petroleum-rich sags continue to be a focus of future oil-gas exploration in the Bohai Bay Basin. There is still a great potential of petroleum resources. Inshore and offshore areas, onshore stratigraphic reservoirs, high-precision exploration in old oilfields, reservoirs inside buried hills, and volcanic reservoirs will contribute a lot in increasing the annual off-gas production and reserves in the basin.

  8. Characteristics of helium isotopes in natural gas and its tectonic implication in Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    DING Weiwei; DAI Jinxin; YANG Shufeng; CHEN Hanlin

    2006-01-01

    Analysis on helium isotopes in natural gas in Bohai Bay Basin showed their mantle-origin indicated by high 3He/4He ratio. The span of 3He/4He ratio increased from west to east. This pattern implied a close relationship to the local tectonic setting. Bohai Bay Basin experienced intensive neo-tectonic activities in the Cenozoic. Widespread faulted-depressions and strong volcanic eruptions manifested its extensional tectonics. Abiogenic natural gas could be released from magmas and migrate upward through deep faults during the extension. Tectonic conditions in the area would favor upward invasion and reservation of mantle-originated helium. Furthermore, with decrease of convergence rate between the Pacific and the Eurasia Plate, the subduction slab of the Pacific Plate rolled back and became steeper, resulting in mantle flow and other tectonic activities migrating from west to east in nature, and caused the variation in isotopic helium ratios.

  9. Geological Conditions Favourable for High-Wax Oil Enrichment in Damintun Depression,Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    Zhu Fangbing

    2009-01-01

    The Damintun (大民屯) depression,a small (about 800 km2 in area) subunit in the Bohai (渤海) Bay basin,hosts nearly 2×108t of high-wax oils with wax contents up to 60%. The high-wax oils have high consolidation temperatures and viscosities.The high-wax oils were generated from the fourth member of the Shahejie Formation (Es4),which is also important source rocks for oils in other subunits of the Bohai Bay basin.Yet high-wax oils have not been found in significant volumes elsewhere in the Bohai Bay basin.Geological conditions favourable for high-wax oil enrichment were studied.This study shows that the unusual concentrations of high-wax oils in the depression seem to result from at least three different factors: (1) the presence of organic-matter rich source rocks which were prone to generate wax-rich hydrocarbons; (2) the formation of early overpressures which increased the expulsion efficiency of waxy hydrocarbons; and (3) reductions in subsidence rate and basal heat flows,which minimized the thermal cracking of high molecular-weight (waxy) hydrocarbons,and therefore prevented the high-wax oils from being transformed into less waxy equivalents.

  10. Meso-Cenozoic Tectono-Thermal Evolution History in Bohai Bay Basin, North China

    Institute of Scientific and Technical Information of China (English)

    Yinhui Zuo; Nansheng Qiu; Jiawei Li; Qingqing Hao; Xiongqi Pang; Zhongying Zhao; Qi Zhu

    2015-01-01

    The thermal history of sedimentary basins is a key factor for hydrocarbon accumula-tion and resource assessment, and is critical in the exploration of lithospheric tectono-thermal evo-lution. In this paper, the Cenozoic thermal histories of nearly 200 wells and the Mesozoic thermal histories of 15 wells are modeled based on the vitrinite reflectance and apatite fission track data in Bohai Bay Basin, North China. The results show that the basin experienced Early Cretaceous and Paleogene heat flow peaks, which reveals two strong rift tectonic movements that occurred in the Cretaceous and the Paleogene in the basin, respectively. The thermal evolution history in Bohai Bay Basin can be divided into five stages including (1) the low and stable heat flow stage from the Trias-sic to the Jurassic, with the heat flow of 53 to 58 mW/m2;(2) the first heat flow peak from the Early Cretaceous to the middle of the Late Cretaceous, with a maximum heat flow of 81 to 87 mW/m2;(3) the first post-rift thermal subsidence stage from the middle of the Late Cretaceous to the Paleocene, with the heat flow of 65 to 74 mW/m2 at the end of the Cretaceous; (4) the second heat flow peak from the Eocene to the Oligocene, with a maximum heat flow of 81 to 88 mW/m2;and (5) the second thermal subsidence stage from the Neogene to present, with an average heat flow of 64 mW/m2.

  11. A Glance at Bohai Bay Oil Province

    Institute of Scientific and Technical Information of China (English)

    Gao Shoubai

    1995-01-01

    @@ Chinese oil industry keeps on developing in 1994. The oil production of Bohai Bay Oil Province located in East China also keeps on growing. Geologically,the total area of Bohai Bay Basin is about 200 000 km2 and the main structural units are: Liaohe Depression, Huanghua Depression,Jizhong Depression, Linqing Depression, Jiyang Depression, Changwei Depression, Bozhong Depression,Chengning Uplift and Cangjing Uplift (see figure 1). Area of the main structural units is listed in following:

  12. Structural Interpretation of the Qingdong Area in Bohai Bay Basin from Shipborne Gravity Data

    Directory of Open Access Journals (Sweden)

    Zhang Chunguan

    2015-09-01

    Full Text Available The Qingdong area, located in Bohai bay basin, was suspected good exploration prospects. In order to study tectonic features and find out favourable petroleum prospects in the area, the gravity data at a scale of 1:50,000 were interpreted. This paper, through data processing and synthetic interpretation of the high-precision gravity data in the area, discusses characteristics of the gravity field and their geological implications, determines the fault system, analyses features of the main strata, divides structure units and predicts favourable petroleum zones. The results showed that the faults controlled the development of the Mesozoic and Cenozoic strata and the distribution of local structures in this area. The study revealed that the Qingtuozi uplift and the Kendong uplift in the north were formed in Mesozoic, and the Qingdong depression in the middle was the rift basin in Mesozoic and Cenozoic. Thicker strata in Mesozoic and Cenozoic developed in the Dongying depression and the Qingdong depression, so there is abundant hydrocarbon in these two depressions, and then the Guangligang rise-in-sag and the Qingdong rise-in-sag developed in the center in these two depressions are also favorable places for prospecting

  13. Distribution and Significance of Methyl Steranes in Bohai Bay Basin, East China

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    31 samples of shales and mudstones developed in reducing hypersaline and freshwater setting and 20 oil samples of Bamianhe oilfield, Bohai Bay basin were collected for a detailed study of petroleum system. Composition and distribution, especially significance of steroids, are discussed as a part of those. Abundant steroidal biomarkers, including C27-29 regular steranes, C28-30 4-methyl steranes, dinosteranes and aromatic steranes, were detected. Results show that the composition and distribution of the steroids in samples studied are functions of thermal maturity, organic source, paleoenvironment and lithology of potential source rocks. Alga-rich Es4 shales (brackish water) developed in the south slope of depocenter (Niuzhuang sag) were found particularly rich in steroidal biomarkers including C30 4-methyl steranes and dinosteranes. Es3 mudstones (fresh water) were found devoid of dinosteranes. Distribution patterns of regular steranes are completely different from methyl steranes indicating different origins of the specific compounds of the fraction. Diagnostic distribution of steranes in rock extracts of diverse intervals makes the compounds to be essential indictors of source-rock tracing. Methyl steranes prove to be much more useful in oil-source rock correlation than regular steranes. Results also show that alga-rich Es4 shales located in the south slope are not likely the primary source rock responsible for the oils discovered based on the composition and distribution of steroids.

  14. Origin and accumulation of the oils from Bamianhe Oilfield, Bohai Bay Basin, Eastern China

    Institute of Scientific and Technical Information of China (English)

    PANG; Xiongqi; LI; Sumei; JIN; Zhijun; LI; Maowen; LI; Pilo

    2004-01-01

    Utilizing basic principles and methodologies of geology and organic geochemistry, kinetics of hydrocarbons generation and accumulation, quantitative assessment of crude oils sourced from different source rocks, and hydrocarbons migration pathways for the oils from the Bamianhe Oilfield, the Bohai Bay Basin, Eastern China are discussed. Results of oil-rock correlation showed that the oils were mainly derived from Es4 member (with buried depth >2700 m) of Niuzhuang and Guangli Sags within normal oil window though there is a little amount of mixed immature oils. Quantification of mixed oils with different sources indicated that mature oils account for about 80% of the total oils discovered and immature oils for only 20%. Migration of the oils sourced from the sags is controlled by predominant hydrocarbons migration passages determined by faults, unformalities and favored sandstone reservoir. Results of the origin and migration models for the oils have been recently further testified by considerable quantity of oils discovered in the Bamianhe area, which is obviously playing an important role in guiding further oil exploration.

  15. Origin of Oils in "Subtle pools" in the Dongying Depression,Bohai Bay Basin, China

    Institute of Scientific and Technical Information of China (English)

    LI Sumei; JIANG Zhengxue; LIU Keyu; QIU Guiqiang; GAO Yongjin

    2008-01-01

    Subtle traps or oil pools have become an important exploration play in the Dongying Depression, Bohai Bay Basin, east China. Despite recent successes in exploration, the formation mechanisms of subtle traps are still not well understood. The majority of subtle oil pools in the Dongying Depression are developed in the middle interval of the Es3 Member of the Paleogene Shahejie Formation with the subtle traps being primarily of lenticular basin-floor turbidite sands encompassed in mudstones. Oil in the subtle traps was previously thought to have migrated directly from the surrounding source rocks of the same formation (Es3). Detailed geochemical investigation of 41 oils and 41 rock samples from the depression now indicates that the oils from the subtle traps cannot be correlated well with the surrounding Es3 source rocks, which are characterized by high Pr/ Ph (>1), low Gammacerane/C30hopane, representing a freshwater lacustrine setting. In contrast the oils features low Pr/Ph (<1) and relatively high Gammacerane content, showing a genetic affinity with the underlying Es4 source rocks, which also have the same qualities, indicating a brackish lacustrine setting. Oils in the Es3 subtle traps are probably derived from mixed sources with the contribution from the upper Es4 source rocks predominating. Therefore unconventional oil migration and accumulation mechanisms need to be invoked to explain the pooling of oils from the Es4 source rocks,which probably came through a thick low interval of the Es3 source rocks with no apparent structural or stratigraphic pathways. We suggest that the subtle oil migration pathway probably plays an important role here. This finding may have significant implications for future exploration and the remaining resource evaluation in the Dongying Depression.

  16. Hydrocarbon Accumulation in Lacustrine Turbidite in the Rift Basin, Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Three types of turbidites are identified in the studied area, including proximal turbidite along the northern steep slope (alluvial fans, fan delta, and subaqueous fans via short-distance transportation), distal turbidites along the southern gentle slope (stacked sliding of delta and fan delta front), and fluxoturbidite in the central depression. Detailed studies of several case histories and the relationship between sedimentary facies and faults suggest a significant role of tectonic setting and faults in the development of turbidite, which created source areas, effected slope topography, controlled the climate and paleo-environment, and formed enough slope angle and slope break for sedimentary instabilities and massive block movement to form turbidite. According to statistics, 0-86%, with an average value of 40.3%, of the trap volumes in the 69 identified Tertiary lacustrine turbidites in the Jiyang Superdepression in the Bohai Bay Basin are filled with oil. The porosity and permeability of turbidite sands vary widely. The productive reservoirs are generally those from the braided channels of both distal and proximal turbidite, and from the main channel of proximal turbidite, with a low carbonate content and the porosity and permeability higher than 12% and 1 mD respectively. Most of the lithologic oil pools in the Jiyang Superdepression are enveloped by the effective source rocks, and the percentage of the trap volume generally increases with the hydrocarbon expulsion intensity of source rocks. This is in contrast with structural-lithologic traps (i.e. proximal turbidite along the steep slope and distal turbidite along the gentle slope), in which, graben-boundary faults play an important role in oil migration, as the turbidites are not in direct contact with effective hydrocarbon source rocks.

  17. Cenozoic lithospheric evolution of the Bohai Bay Basin, eastern North China Craton: Constraint from tectono-thermal modeling

    Science.gov (United States)

    Liu, Qiongying; He, Lijuan; Huang, Fang; Zhang, Linyou

    2016-01-01

    It is well established that the lithosphere beneath the eastern North China Craton (NCC) had been thinned before the Cenozoic. A 2D multi-phase extension model, in which the initial crustal and lithospheric thicknesses are variable, is presented to reconstruct the initial thicknesses of the crust and lithosphere in the early Cenozoic and to further investigate the lithospheric evolution beneath the eastern NCC through the Cenozoic. We conduct thermal modeling along three profiles from east to west in the Bohai Bay Basin, which is the center of the lithospheric destruction and thinning of the NCC. Using multiple constraints, such as tectonic subsidence, the present-day heat flow and the Moho depth, we determine the initial crustal and lithospheric thicknesses of the Bohai Bay Basin before the Cenozoic rift to be 33-36 km and 80-105 km, respectively. The model results show that the most rapid lithospheric thinning during the Cenozoic occurred in the middle Eocene for most depressions, and the thinning activity ceased at the end of the Oligocene, reaching a minimum lithospheric thickness of 53-74 km, followed by a thermal relaxation phase. Combined with previous studies, we infer that the lithosphere beneath the eastern NCC experienced two stages of alternating thinning and thickening: notable thinning in the Early Cretaceous and Paleogene, and thickening in the Late Cretaceous and late Cenozoic. We believe that thermo-chemical erosion, together with extension, was probably the major mechanism of the significant lithospheric removal during the Mesozoic, whereas the Cenozoic lithospheric thinning was mainly dominated by tectonic extension in the eastern NCC; lithospheric thickening was generally a result of thermal cooling.

  18. Seismically induced soft-sediment deformation structures in the Palaeogene deposits of the Liaodong Bay Depression in the Bohai Bay basin and their spatial stratigraphic distribution

    Science.gov (United States)

    Liu, Lei; Zhong, Yijiang; Chen, Hongde; Xu, Changgui; Wu, Kui

    2016-08-01

    Soft-sediment deformation structures (SSDS) have been identified from well cores in the Palaeogene deposits of the Liaodong Bay Depression in the Bohai Bay basin, China. These deposits formed as interbedded sand and mud at a delta front or on the slope toe of the prodelta. According to criteria proposed by previous research, we established that these SSDS were induced by earthquakes and that they can be divided into two groups: ductile deformation structures (plastic intrusions, ball-and-pillow structures, flame structures, boudinage structures, irregular convolute stratifications, and synsedimentary faults and folds) and brittle deformation structures (sand dykes and autoclastic breccias). Based on their level of deformation, size, and complexity, the SSDS were divided into three Groups, from weak to strong, to reflect the intensity of palaeo-earthquakes. With consideration of the palaeo-sedimentary environment, we proposed a model to account for the production and preservation of these SSDS. According to the classification adopted in this study and the spatial stratigraphic distribution of the SSDS, the tectonic activities of the Tan-Lu faults in the Bohai Bay basin were investigated. The A and B oilfields (assumed names) are located in the tectonically active zones of the west and east branches of these faults, respectively. The extension tectonic activities in the A oilfield region exhibit a sharply decreasing trend from E2s3 to E2s1, and increase again in E3d2; whereas the strike-slip tectonic activities in the B oilfield region exhibit an increasing trend from E2s3 to E2s1, and finally, reach a maximum to E3d3. The results of this study show that the method of analysis of the spatial stratigraphic distribution of SSDS is suitable for determining the evolution of tectonic activity and thus, it can provide a new perspective for basin analysis.

  19. Meso-Cenozoic thermal-rheological evolution in Jiyang sub-basin, Bohai Bay Basin and its implication for basin extension revealed by numerical modelling

    Science.gov (United States)

    Li, Lu; Qiu, Nansheng; Xu, Wei

    2016-04-01

    Jiyang sub-basin is an oil-rich depression located in the southeast of Bohai Bay Basin, which is one of the most important hydrocarbon area in east of China. The thermal-rheological structure of the lithosphere can explain the dynamics evolution processes of basins, continental margins and orogenic belts, which directly reflects the characteristics of the lithosphere geodynamics. Nevertheless it is poorly to understand the evolution of lithospheric thermal-rheological structure in Jiyang sub-basin and its implication for basin extension. In this study, two dimensional numerical modelling is applied to calculate the paleo-temperature field and the thermo-lithospheric structure, which are used to estimate the evolution of lithospheric thermal-rheological structure. The results of study show that in Mesozoic the lithosphere was of relative rigidity and stable, as featured by large thickness and strength whereas after late Cretaceous the lithospheric strength decreased rapidly. The analysis of thermal-rheological properties shows that the lithospheric thermo-lithospheric structure is sandwiched-like with two ductile layers and two brittle layers. The upper crust is usually brittle. The brittle layers appear at outer 20km of the crust, below 20km ductile deformation predominates. There is also a 10km brittle layer on the top of the upper mantle. The integrated lithospheric yield strength is about 1.3-4.5×1012N/m, showing a weak lithosphere which may support the idea that the extension achieved by the ductile flow below the brittle layers. Keywords: lithospheric thermal-rheological structure; Jiyang sub-basin; Numerical modeling

  20. Depositional Patterns and Oil/Gas Accumulation Features of Sha-3 Member Turbidites in Dongying Depression, Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    BaiGuoping; ZhangShanwen

    2004-01-01

    Recent exploration results indicate that a significant exploration potential remains in the Dongying Depression of the Bohai Bay Basin and the undiscovered oil and gas are largely reservoired in subtle traps including turbidite litholigeal traps of the Sha-3 Member. In order to effectively guide the exploration program targeting turbidites, this study will focus on the depositional models of the Sha-3 Member turbidites and oil/gas accumulation characteristics in these turbidites. Two corresponding relationships were found. One is that the East African Rift Valley provides a modem analog for the depositionai systems in the Dongying Depression. The other is that the depositional models of line-sourced slope aprons, single point-source submarine fan and multiple source romp turbidite, established for deep.sea turbidites, can be applied to interpret the depositional features of the turbidite fans of three differant origins: slope turbidite aprons, lake floor turbidite fans and delia-fed turbidite fans in the Sha-3 Member. Updip sealing integrity is the key factor determining whether oil/gas accumulates or not in the slope aprons and lake floor fans. The factors controlling oil/gas migration and accumulation in the delta-ted turbidite fans are not very clear. Multiple factors rather than a single factor probably played significant roles in these processes.

  1. The control of syndepositional faulting on the Eogene sedimentary basin fills of the Dongying and Zhanhua sags,Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    LIN Changsong; ZHENG Herong; REN Jianye; LIU Jingyan; Qiu Yigang

    2004-01-01

    The Dongying and Zhanhua sags are the major hydrocarbon exploration and production subbasins in the Bohai Bay Basin. Integrated analysis of the sedimentary basin fills has shown that the syndepositional faults and their arrangement styles exerted an important influence on the development and distribution of the Eogene depositional systems. The sedimentary filling evolution of the subbasins reflects the general control of the episodic rifting process. The major long-term active normal faults formed a series of paleogeomorphic accident or slopebreak zones that commonly delineated the subsidiary palaeostructural units and the depositional facies tracts and constrained the general distribution of sedimentary facies zones. The central sag boundary fault slopebreak zones usually determined the distribution of the depocenters of terrestrial clastic depositional systems, particularly the Iowstand fans or deltaic depositional systems, and have proven to be the economically important targets for the exploration of subtle sandstone reservoirs. A variety of syndepositional fault arrangement patterns, including the parallel, en echelon, combo-like, broom-like fault systems and the fault overlap or transfer zones,have been recognized in the subbasins. They generated distinctive geomorphic features and exerted a direct influence on sediment dispersal and sandbody distribution during the Eogene synrift stage. It is the key for the prediction of depositional systems tracts and reservoir sandstones to investigate the activity and distribution of the fault slopebreak zones and reconstruct the structural paleogeomorphy in different basin filling stages of the basin evolution.

  2. Quantitative Assessment of Hydrocarbon Expulsion of Petroleum Systems in the Niuzhuang Sag,Bohai Bay Basin,East China

    Institute of Scientific and Technical Information of China (English)

    PANG Xiongqi; LI Sumei; JIN Zhijun; BAI Guoping

    2004-01-01

    Based on a detailed survey of the distribution and organic geochemical characteristics of potential source rocks in the South Slope of the Niuzhuang Sag, Bohai Bay Basin, eastern China, a new approach to assess the amount of hydrocarbons generated and expelled has been developed. The approach is applicable to evaluate hydrocarbons with different genetic mechanisms. The results show that the models for hydrocarbon generation and expulsion vary with potential source rocks, depending on thermal maturity, types of organic matter and paleoenvironment. Hydrocarbons are mostly generated and expelled from source rocks within the normal oil window. It was calculated that the special interval (algal-rich shales of the Es4 member formed in brackish environments) in the South Slope of the Niuzhuang Sag has a much higher potential of immature oil generation than the other intervals in the area. This suggests that hydrocarbons can definitely be generated in early diagenesis, especially under certain special geological settings. The proportion of hydrocarbons generated and expelled from the Es4 shales in the early diagenetic stage is up to 26.75% and 17.36%,respectively. It was also observed that laminated shales have a much higher expulsion efficiency than massive mudstones.In contrast, the special interval of the Es4 shales proposed from previous studies is probably not the whole rock for oil in the South Slope of the Niuzhuang Sag because of the small proportion of the gross volume and corresponding low percentage of hydrocarbons generated and expelled. A much lower expulsion efficiency of the source rock during the early stage relative to that within the normal oil window has been calculated. Our results indicate that the Es4 mudstones rather than the shales deposited in the Niuzhuang and Guangli Sag are the main source rocks for the oil discovered.

  3. Mesozoic Cenozoic tectonic evolution of the Zhuanghai area, Bohai-Bay Basin, east China: the application of balanced cross-sections

    Science.gov (United States)

    Wu, Shiguo; Yu, Zhaohua; Zhang, Rongqiang; Han, Wengong; Zou, Dongbo

    2005-06-01

    The technique of balancing cross-sections, an important method for studying the tectonic history of sedimentary basins, has many applications. It enables one to compile charts for petroleum exploration and development, and growth sections of ancient structures can be restored so that the structural growth history can be studied. In order to study tectonic evolution in the Zhuanghai area of the Bohai-Bay basin, we selected two seismic profiles and compiled two structural growth sections. Based on the two balanced cross-sections, the evolution can be divided into four phases: the Triassic-Middle Jurassic phase, Late Jurassic-Cretaceous phase, Palaeogene extension phase, and Late Palaeogene-to-present phase. The whole area was uplifted during the Triassic-Middle Jurassic phase because of intense extrusion stress related to the Indo-China movement. During the Late Jurassic and Early Cretaceous, intense extension occurred in east China, and the whole area rifted, leading to the deposition of a thick sedimentary sequence. In the Late Cretaceous, the area suffered uplift and compression associated with the sinistral strike slip of the Tanlu fault. In the Palaeogene, a rifting basin developed in the area. Finally, it became stable and was placed in its present position by dextral strike-slip motion. In addition, some problems associated with compiling balanced cross-sections are discussed.

  4. 渤海湾盆地变换构造特征及其成藏意义%Transfer structure and its relation to hydrocarbon exploration in Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    杨明慧

    2009-01-01

    On the basis of the previous classification research, the features of transfer structure in Bohai Bay Basin were analyzed. The transfer structures in Bohai Bay Basin can be divided into two styles of transfer zone and transfer fault according to the connec-tion or non-connection status. The transfer structure in Bohai Bay Basin is mainly exhibited in the style of transfer zone, especially in basin or depression, while the transfer fault only militates in the sag-control level. With the occasional development of transfer fault, most of high-level transfer zones are horizontally connected with different relay ramps. These strike transfer structures in NWW-NW direction are the most important structure styles to control the "north-south segmentation" tectonic framework in Bohai Bay Basin. The difference of oil and gas reserves in Bohai Bay Basin is related to the distribution of prolific hydrocarbon depressions and sags controlled by transfer structure. The paleotopography and rich-sand drainage channels controlled by transfer structure are favorable to the formation of lithologic reservoirs. The adjacent zones of the transfer structure are the important regions for finding the buried-hill structure reservoirs.%依据前人对变换构造的分类研究,分析了渤海湾盆地变换构造的特征.将渤海湾盆地变换构造分为变换带和变换断层两种类型:一般表现为变换带样式,尤其是在盆地或坳陷层次;而变换断层仅在局部的控凹层次上有所体现.高级别的变换带大多数是由一系列不同类型的传递斜坡横向串联而成,间或发育变换断层.北西西-北西向的变换构造是渤海湾盆地"南北分块"构造格局的主控构造样式,而渤海湾盆地油气储量的差异与变换构造控制的富生烃凹陷及洼陷分布有关.变换构造控制的古地形和富砂水系通道有利于形成岩性油气藏,变换构造邻区的高部位则是发现(潜山)构造油气藏的重要地区.

  5. Core evidence of paleoseismic events in Paleogene deposits of the Shulu Sag in the Bohai Bay Basin, east China, and their petroleum geologic significance

    Science.gov (United States)

    Zheng, Lijing; Jiang, Zaixing; Liu, Hui; Kong, Xiangxin; Li, Haipeng; Jiang, Xiaolong

    2015-10-01

    The Shulu Sag, located in the southwestern corner of the Jizhong Depression, Bohai Bay Basin of east China, is a NE-SW trending, elongate Cenozoic half-graben basin. The lowermost part of the third member of the Shahejie Formation in this basin is characterized by continental rudstone and calcilutite to calcisiltite facies. Based on core observation and regional geologic analysis, seismites are recognized in these lacustrine deposits, which include soft-sediment deformation structures (sedimentary dikes, hydraulic shattering, diapir structures, convolute lamination, load-flame structures, ball-and-pillow structures, loop bedding, and subsidence structures), synsedimentary faults, and seismoturbidites. In addition, mixed-source rudstones, consisting of the Paleozoic carbonate clasts and in situ calcilutite clasts in the lowermost submember of Shahejie 3, appear in the seismites, suggesting an earthquake origin. A complete representative vertical sequence in the lowermost part of the third member found in well ST1H located in the central part of the Shulu Sag shows, from the base to the top: underlying undeformed layers, synsedimentary faults, liquefied carbonate rocks, allogenetic seismoturbidites, and overlying undeformed layers. Seismites are widely distributed around this well and there are multiple sets of stacked seismites separated by undeformed sediment. The nearby NW-trending Taijiazhuang fault whose fault growth index is from 1.1 to 1.8 and the NNE-trending Xinhe fault with a fault growth index of 1.3-1.9 may be the source of the instability to create the seismites. These deformed sedimentary layers are favorable for the accumulation of oil and gas; for example, sedimentary dikes can cut through many layers and serve as conduits for fluid migration. Sedimentary faults and fractures induced by earthquakes can act as oil and gas migration channels or store petroleum products as well. Seismoturbidites and mixed-source rudstones are excellent reservoirs due to

  6. Quantitative prediction of mixed-source crude oils and its significance for understanding oils accumulation in subtle pools in the Dongying Depression,Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    Li Sumei; Liu Keyu; Pang Xiongqi; Li Maowen; Jiang Zhenxue; Qiu Guiqiang; Gao Yongjin

    2008-01-01

    Conventional geochemical approaches were utilized in the quantitative prediction of the proportions of mixed-source crude oils derived from the Es3 and Es4 members of the Paleogene Shahejie Formation.The mixed-source oils are accumulated in the middle interval of the Es3 member(EsM3)in the Niuzhuang Sag,which is one of the sags where subtle traps are primarily of lenticular basin-floor turbidite sands within mudstones mostly developed in the Dongying Depression,Bohai Bay Basin.The result showed that about 18-92% of the mixed-source oils were derived from the Es4 source rocks with an average of 55-60%.Reservoirs associated with deep faults appear to have much more Es4 genetic affinity oils.A high proportion of the Es4-derived oils discovered in the Es3M subtle lithological traps in the Niuzhuang Sag have long migration distances.This suggests that surrounding source rocks might not necessarily control the hydrocarbon supply for subtle traps.Subtle migration pathway may play an important role in the vertical oil migration.The traditional concept of hydrocarbons accumulation in these lenticular turbidite sandstone traps within a short migration distance from the surrounding source rocks is not supported by this study.The present result is also consistent with our previous findings that immature oils in the Bamianhe Oilfield in the south slope of the Niuzhuang Sag were actually mixed-source oils mostly sourced from the Es4 in the depocenter of the Niuzhuang Sag,and the petroleum potential of the Es4 member in the Dongying Depression should therefore be re-evaluated.

  7. Biodegraded Oil and Its High Molecular Weight (C35+) n-alkanes in the Qianmiqiao Region in the Bohai Bay Basin, Northern China

    Institute of Scientific and Technical Information of China (English)

    WANG Tieguan; ZHU Dan; LU Hong; ZHANG Zhihuan; YANG Chiyin

    2004-01-01

    With a production of 208.2 m3/d, heavy oil was produced by drill stem test (DST) from three shallow reservoirs in Sand Group Nos. Ⅰ and Ⅲ of the Neogene Guantao Formation (Ng1 and NgⅢ) and the Eogene Dongying Formation (Ed) in an exploratory well Ban-14-1 within the Qianmiqiao region, Bohai Bay Basin, northern China. Based on the GC and GC-MS data of theNgⅠand NgⅢheavy oil samples, all n-alkanes and most isoprenoid hydrocarbons are lost and the GC baseline appears as an evident "hump", implying a large quantity of unresolved complex mixture (UCM),which typically revealed a result of heavy biodegradation. However, there still is a complete series of C14-C73 n-alkanes in the high-temperature gas chromatograms (HTGC) of the heavy oil, among which, the abundance of C30- n-alkanes are drastically reduced. The C35-C55 high molecular weight (HMW) n-alkanes are at high abundance and show a normal distribution pattern with major peak at C43 and an obvious odd-carbon-number predominance with CPI37-55 and OEP45-49values of 1.17 and 1.16-1.20, respectively. According to GC-MS analysis, the heavy oil is characterized by dual source inputs of aquatic microbes and terrestrial higher plants. Various steranes and tricyclic terpanes indicate an algal origin, and hopane-type triterpanes, C24tetracyclic terpane and drimane series show the bacterial contribution. With the odd-carbonnumber preference, HMW n-alkanes provide significant information not only on higher plant source input and immaturity,but also on the strong resistibility to biodegradation.

  8. Origin of sulfur rich oils and H2S in Tertiary lacustrine sections of the Jinxian Sag, Bohai Bay Basin, China

    International Nuclear Information System (INIS)

    Very high S oils (up to 14.7%) with H2S contents of up to 92% in the associated gas have been found in the Tertiary in the Jinxian Sag, Bohai Bay Basin, PR China. Several oil samples were analyzed for C and S stable isotopes and biomarkers to try to understand the origin of these unusual oil samples. The high S oils occur in relatively shallow reservoirs in the northern part of the Jinxian Sag in anhydrite-rich reservoirs, and are characteristic of oils derived from S-rich source rocks deposited in an enclosed and productive stratified hypersaline water body. In contrast, low S oils (as low as 0.03%) in the southern part of the Jinxian Sag occur in Tertiary lacustrine reservoirs with minimal anhydrite. These southern oils were probably derived from less S-rich source rocks deposited under a relatively open and freshwater to brackish lake environment that had larger amounts of higher plant inputs. The extremely high S oil samples (>10%) underwent biodegradation of normal alkanes resulting in a degree of concentration of S in the residual petroleum, although isoprenoid alkanes remain showing that biodegradation was not extreme. Interestingly, the high S oils occur in H2S-rich reservoirs (H2S up to 92% by volume) where the H2S was derived from bacterial SO4 reduction, most likely in the source rock prior to migration. Three oils in the Jinxian Sag have δ 34S values from +0.3%o to +16.2%o and the oil with the highest S content shows the lightest δ 34S value. This δ 34S value for that oil is close to the δ 34S value for H2S (∼0%o). It is possible that H2S was incorporated into functionalized compounds within the residual petroleum during biodegradation at depth in the reservoir thus accounting for the very high concentrations of S in petroleum

  9. Multi-origin alkanes related to CO2-rich, mantle-derived fluid in Dongying Sag, Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    With the newly obtained carbon isotope data for the natural gas, a pilot study of multiple-sourced alkanes related to the mantled-derived fluid is presented. The carbon isotope values of alkanes in the Dongying Sag possess thefea tures indicating a general organic origin. However, there are two sub-populations in the isotopic data set, which reflect two specific types of origins. In gene ral, the sub-population with high δ13CCH4 values is related to the CO2-rich, mantle-derived fluid, and it is distributed in the belts where mantle-derived fluid flow and basic volcanic activities have occurred. Geological and geochemical studies demonstrate that this variation of methane carbon isotope values in the Dongying Sag is unrelated with the basin bury and thermal histories, types of source rocks, and reactions between basin fluid and rocks. Mixing of mantle-derived fluid and organic sourced hydrocarbons is probably the cause for the variation .

  10. Sequence Stratigraphic Delineation and Correlation of the Dongying Formation in the Nearshore and Adjacent Sea Areas, Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    Zhu Hongtao; Du Yuansheng; Liu Keyu; Yan Jiaxin; Xu Yajun; Yang Ping; Liu Xinyu

    2008-01-01

    Based on the analysis of well logs, seismic data, core studies, the Dongying (东营) into three third-order sequences from base to top: namely, sequences SQ1, SQ2 and SQ3. The three sequences have different wireline (SP) log responses, showing triple-section characteristics with SQ1 being characterized by primarily flat baseline with intercalation of relatively low spontaneous potential, SQ2 generally exhibiting weak or moderate amplitude spontaneous potential with finger-shaped peaks, and SQ3 having relatively high spontaneous potential with funnel-shaped log curves. On the basis of the triple-section characteristics, the stratigraphic sequences can be correlated consistently throughout the entire study area. A stratigraphic and sedimentary model for sequences SQ1 to SQ3 of the Dongying Formation in the study area has been proposed. The accommodation space change in the two sides of the asymmetrical basin was examined and the asymmetrical basin has the feature of the asymmetrical accommodation space change. The asymmetrical physiography is a vital factor to influence the accommodation changes in additional to the lake level change, tectonism and sediment supply. This may have important implications to similar basins in other parts of China or elsewhere.

  11. Bohai Bay, Focus Area to Meet Energy Need

    Institute of Scientific and Technical Information of China (English)

    Cui Xiaojin

    2002-01-01

    @@ Chevron-Texaco, Petronas Carigali and CNOOC Limited have confirmed an oil discovery in Bohai Bay area. Ru Ke, senior vice president of CNOOC Limited, said the exploration is evidence of the huge oil potential in the bay. Several other major discoveries have been made in the bay in the recent years. Sam Snyder, managing director of ChevronTexaco's China business unit, said he had big hopes for high-quality oil and high production rates. Under the production sharing contract, CNOOC Limited has the right to take up to a 51 percent interest in development of the oil discovery.

  12. Heavy metal pollution in Tianjin Bohai Bay, China

    Institute of Scientific and Technical Information of China (English)

    MENG Wei; QIN Yanwen; ZHENG Binghui; ZHANG Lei

    2008-01-01

    The contamination levels and distribution characters of heavy metals in coastal waters and sediments from Tianjin Bohai Bay, China were examined, and it was found that the main heavy metal pollutants in the coastal waters of the bay were Pb and Zn. High levels of Pb and Zn appeared especially near the estuary, indicating that river discharge was the main pollution source. Moreover, atmospheric deposition resulted in Pb contamination in the middle of the embayment. Analysis of data for the period 1987-2004 indicated that Pb pollution in coastal waters of Bohai Bay originated primarily from river discharge before 2001. Pb levels did not decrease after 2001 when annual runoff levels declined; indicating that Pb pollution by atmospheric deposition had increased due to the use of leaded petrol in motorcars. Pb, Zn and Cd were the dominant polluting elements in surficial sediments from Tianjin Bohai Bay, with levels in excess of the corresponding upper limits of environmental background values. Higher concentrations of polluting elements were found in tidal sediments near water bodies such as Qikou and Dagu estuaries.

  13. WATER POLLUTION IN THE RIVER MOUTHS AROUND BOHAI BAY

    Institute of Scientific and Technical Information of China (English)

    Cheng LIU; Zhao-Yin WANG; Yun HE

    2003-01-01

    Twelve water samples were collected and analyzed. The samples were taken from the river mouths around Bohai Bay including the Jiyun, New Yongding, Haihe, Dagu, Duliujian, Qingjinghuang, Qikou, Dakou, and Yellow Rivers, and tested for concentrations of heavy metals, arsenic, total nitrogen (TN) and total phosphorus (TP). The results show that the river mouths are polluted and the water quality exceeds Class V of the Environmental Quality Standard for Surface Water (EQSSW). The main pollutants are Hg, nitrogen (N) and phosphorus (P). The concentrations of the other pollutants are within Class Ⅱ of the Standard. The Hg content in the Haihe River mouth is now 10 times higher than it was 20 years ago, indicating that the accelerating water pollution has reached an alarming level. The high concentrations of N and P cause eutrophication of the waters.Analysis indicates that the terrestrial pollutants and nutrients are the main cause of frequently occurring red tides in the Bohai Sea.

  14. Evolution of Meso-Cenozoic lithospheric thermal-rheological structure in the Jiyang sub-basin, Bohai Bay Basin, eastern North China Craton

    Science.gov (United States)

    Xu, Wei; Qiu, Nansheng; Wang, Ye; Chang, Jian

    2016-07-01

    The Meso-Cenozoic lithospheric thermal-rheological structure and lithospheric strength evolution of the Jiyang sub-basin were modeled using thermal history, crustal structure, and rheological parameter data. Results indicate that the thermal-rheological structure of the Jiyang sub-basin has exhibited obvious rheological stratification and changes over time. During the Early Mesozoic, the uppermost portion of the upper crust, middle crust, and the top part of the upper mantle had a thick brittle layer. During the early Early Cretaceous, the top of the middle crust's brittle layer thinned because of lithosphere thinning and temperature increase, and the uppermost portion of the upper mantle was almost occupied by a ductile layer. During the late Early Cretaceous, the brittle layer of the middle crust and the upper mantle changed to a ductile one. Then, the uppermost portion of the middle crust changed to a thin brittle layer in the late Cretaceous. During the early Paleogene, the thin brittle layer of the middle crust became even thinner and shallower under the condition of crustal extension. Currently, with the decrease in lithospheric temperature, the top of the upper crust, middle crust, and the uppermost portion of the upper mantle are of a brittle layer. The total lithospheric strength and the effective elastic thickness (T e) in Meso-Cenozoic indicate that the Jiyang sub-basin experienced two weakened stages: during the late Early Cretaceous and the early Paleogene. The total lithospheric strength (approximately 4-5 × 1013 N m-1) and T e (approximately 50-60 km) during the Early Mesozoic was larger than that after the Late Jurassic (2-7 × 1012 N m-1 and 19-39 km, respectively). The results also reflect the subduction, and rollback of Pacific plate is the geodynamic mechanism of the destruction of the eastern North China Craton.

  15. Murky Waters The Bohai Bay oil spill brings China's marine liability laws into focus

    Institute of Scientific and Technical Information of China (English)

    WANG HAIRONG

    2011-01-01

    Scallop farmers in Laoting County in north China's Hebei Province had been unaware a catastrophe was approaching their farms south of the Bohai Bay until late June when they found millions of young scallops dead.

  16. Commercial Oil Discovery in Zhao Dong Block of Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    Lin Rujin; Zhu Xiangdong

    1995-01-01

    @@ China National Oil and Gas Exploration and Development Corporation (CNODC) and XCL-China,Ltd.(XCL) signd the contract for petroleum exploration, development and Production on Zhao Dong Block in Bohai Bay shallow water sea area of P.R.C. on Feb. 10, 1993. The contract area is 197 square kilometers. XCLacts as the Operator for the petroleum operations within the contract area in accordance with the provisions of the contract. In Feb. 1994, XCL assigned one third of its share to Apache China Corporation, and Apache has become the partner of XCL since then. This contract is the first petroleum contract as well as the first cooperative project which gained commercial discovery after CNPC announced to expand the petroleum co-operation with foreign firms on China onshore.

  17. 冀中坳陷潜山油气运聚动力学特征及其类型%DYNAMIC MODELS OF PETROLEUM MIGRATION AND ACCUMULATION FOR PALEOZOIC-PROTEROZOIC BURIED HILLS IN JIZHONG DEPRESSION, BOHAI BAY BASIN

    Institute of Scientific and Technical Information of China (English)

    邹华耀; 向龙斌; 梁宏斌; 朱庆忠

    2001-01-01

    The comprehensive analysis of fluid pressure field, fluidchemical field and fluid-migrating conduits of buried hills in Jizhong depression, Bohai Bay basin classifies the buried hills as the following three major dynamic categories of petroleum migration and accumulation: (1) unconformity-connected-open buried hills (Type Ⅰ),(2) fault conduit-semi-open/semi-closed buried hills (Type Ⅱ), and (3) closed buried hills (Type Ⅲ). Type I buried hills are connected with the regional underground hydrodynamic system located in the middle part of the Jizhong depression where is present a sufficient supply of the petroleum and gas that may result in the formation of large-scale hydrocarbon pools in the buried hills. Type Ⅱ buried hills occur in the slopes close to the hydrocarbon-generated sags, with the seismic pumping conduits in the buried hill-associated faults serving as the acting force on the petroleum and gas migration and accumulation, exhibiting an excellent condition for the petroleum pools. Type Ⅲ buried hills scattered within the depression zone with a relatively great degree of subsidization occur separately and are overlapped by the Tertiary abnormally high pressure zone, restraining the acting force of the fluid conduits associated with the buried hills. In this case, the buried hills in the closed system with the relatively poor condition of petroleum and gas migration and accumulation may accommodate small-sized petroleum and gas pools of the buried hills with great exploration risks.%依据冀中坳陷潜山流体压力场、流体化学场及流体运移通道等特征的综合研究,将潜山分为三种运聚动力学类型:不整合连通-开放型潜山(Ⅰ型)、断层通道-半开放/半封闭型潜山(Ⅱ型)和封闭型潜山(Ⅲ型).Ⅰ型潜山与冀中坳陷中部区域性地下水动力系统相连通,油气源充足,可形成大规模的潜山油气藏.Ⅱ型潜山分布于紧邻生烃洼陷的斜坡区,潜山相关

  18. 渤海湾盆地沾化凹陷富林洼陷油气来源及分布规律研究%Hydrocarbon origin and distribution regularity in Fulin sub-Sag, Zhanhua Sag, Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    王秀红

    2013-01-01

      通过对渤海湾盆地沾化凹陷富林洼陷原油的生物标志物分布与组合特征分析,认为该区主要存在3类原油:Ⅰ类原油主要分布于东次洼,呈植烷优势,伽马蜡烷含量高,重排甾烷与4-甲基甾烷含量较低,来源于东次洼本身的沙四上亚段烃源岩;Ⅱ类原油分布于中次洼洼陷内部,具有姥鲛烷优势、伽马蜡烷含量低、重排甾烷含量高的特征,纵向上不同储层油气来源存在差异,其中浅部储层油气来源于孤南洼陷沙三下亚段烃源岩,深部储层油气主要来自于富林洼陷沙三下亚段烃源岩;Ⅲ类原油分布于中次洼断裂带附近,成熟度较低,姥鲛烷优势,伽马蜡烷含量中等,C28甾烷含量丰富,孕甾烷和重排甾烷含量较低,为孤南洼陷沙一段与富林洼陷沙三下亚段烃源岩所形成的混源油。%Based on the studies of biomarker distribution and composition of crude oils in the Fulin sub-Sag of the Zhanhua Sag of the Bohai Bay Basin, there are 3 types of crude oil in the study area. The crude oils of typeⅠ mainly exist in the east of the sub-sag, characterized by low Pr/ Ph ratio, high gammacerence content as well as low diasterane and 4-methyl-sterane contents. They are originated from source rocks in the upper subsection of the 4th member of the Shahejie Formation in the east of the sub-sag. The crude oils of type Ⅱ mainly locate in the center of the sub-sag, featured by high Pr/ Ph ratio, low gammacerence content and high diasterane content. The origin for oil and gas is different vertically. Hydrocarbon in the middle and shallow reservoirs is mainly origi-nated from source rocks in the lower subsection of the 3rd member of the Shahejie Formation in the Gunan sub-Sag while hydrocarbon in the deep reservoir is mainly originated from source rocks in the lower subsection of the 3rd member of the Shahejie Formation in the Fulin sub-Sag. The crude oils of type Ⅲ mainly distribute around fault

  19. THE FURTHER DEEPENING OF OIL-GAS ACCUMULATION THEORY AND EXPLORATORY PRACTICE OF BOHAI BAY BASIN%渤海湾盆地油气聚集理论和勘探实践的再深化——为渤海湾含油气盆地发现40周年而作

    Institute of Scientific and Technical Information of China (English)

    胡见义; 牛嘉玉

    2001-01-01

    渤海湾含油气盆地发现40年来已建成为我国最大的油区。同时,也形成与建立了第三系裂谷系油气藏形成与分布理论,包括裂谷系对含油气断陷和含油气层系的控制、普遍存在多含油气结构层系、复式油气聚集区带形成、油气藏类型特点及圈闭边界组合以及含油气单元序列与油气勘探评价阶段的划分等。勘探特点与储量增长受新领域突破和理论技术与勘探融合的明显影响。渤海湾盆地至今仍有许多勘探领域和很大的油气潜力。%The largest oil-productive base in China has been established inBohai Bay Basin since its hydrocarbon discovery 40 years ago.Meanwhile,the theory on formation and distribution of oil-gas reservoirs in Tertiary rift has been completed a lot. It involves in multiple oil-gas-bearing structural sequences, multiple oil-gas accumulation zones,oil-gas reservoir types, trap boundary combination,oil-gas-bearing unit,and classification of petroleum exploration and evaluation stages and so forth. Exploration features and increase in reserve are obviously influenced by breakthroughs in frontier areas,and the application of theory and technology in exploration. So far,there are still many exploration frontier areas and great hydrocarbon potential in Bohai Bay Basin.

  20. Short- and long-term sediment transport in western Bohai Bay and coastal areas

    Science.gov (United States)

    Feng, Huan; Zhang, Weiguo; Jia, Li; Weinstein, Michael P.; Zhang, Qiufeng; Yuan, Dekui; Tao, Jianhua; Yu, Lizhong

    2010-05-01

    Sediment cores (˜40-100 cm) were collected at 12 locations in the western Bohai Bay, the Haihe River estuary, the Yongding River estuary and the Tianjin Harbor, China, during 24-26 July 2007, and analyzed for 7Be and 210Pb activities. Due to localized hydrodynamic patterns and frequent disturbance from dredging activities, steady-state sedimentation features were not observed in this study. As demonstrated in the 7Be and 210Pb profiles, the temporal and spatial variations of these radionuclides support a non-steady state depositional environment in the study area. By comparing 7Be and 210Pb inventories in the sediments with those of the atmospheric source, we found that: 1) sediments dredged from the Tianjin Harbor or eroded from nearby estuarine and coastal areas are retained in the western Bohai Bay for relatively short intervals (several months), as reflected in the relatively high 7Be inventories in the western Bohai Bay; 2) over the long-term (years to decades), 210Pb inventories in the sediments imply that there is a net on-shore transport of sediments, and the sediments are mass-balanced in the entire study area. Overall, our results suggest that the sediments are retained in the estuaries and the western Bohai Bay despite local variability in sediment dynamics and disturbance due to human activities.

  1. Sedimentary dynamics along the west coast of Bohai Bay, China, during the twentieth century

    DEFF Research Database (Denmark)

    Wang, Fu; Wang, Huang; Zong, Y.;

    2014-01-01

    To investigate the most recent changes in sedimentation along the west coast of Bohai Bay, China, we collected twelve 1–2 m short cores of undisturbed sediment from tidal flats off the city of Tianjin, using an Eijkelkamp corer. Based on the excess or unsupported 210Pb and 137Cs activities measured...

  2. Application of Artificial Neural Network in the Research of the Bohai Bay Eutrophication

    Institute of Scientific and Technical Information of China (English)

    WU Qing; ZHAO Xinhua; ZHAO Quan

    2007-01-01

    In order to research the feasibility of artificial neural network (ANN) in the research of eutrophication of the Bohai Bay in China, an ANN model simulating chlorophyll a, b and c concentrations, concerning temperature, dissolved oxygen, salinity, pH value, chemical oxygen demand(COD), PO43- , NO2- and NO3- factors in the Bohai Bay was presented and validated. After experiencing and training by Matlab, the model's validation mean square error (MSE) performance is0.009 985 02. R-squared between estimated and observed concentrations of chlorophyll a, b and care 0.965 7, 0.998 7 and 0.970 7 respectively, indicating that the estimated value agrees with the observed value well, and the model can be used in the prediction of eutrophication of the Bohai Sea. In order to study the influence of model input factors on chlorophyll concentration (I. E. Model outputs), hypothetical scenarios were introduced to show model output responses to variations in in-put factors. The limitation of temperature, salinity and phosphate that induce red tide in the Bohai Bay was also presented.

  3. Mechanisms of Cenozoic deformation in the Bohai Basin, Northeast China: Physical modelling and discussions

    Institute of Scientific and Technical Information of China (English)

    ZHOU; Jianxun; ZHOU; Jiansheng

    2006-01-01

    The Bohai Basin is a Cenozoic petroliferous extensional basin in China and has apparent geometrical and kinematic similarities with the other Meso-Cenozoic extensional basins located along the eastern margin of Eurasian Plate. However, the deformation mechanisms of the basin are still in dispute. Physcial modelling referring to the Huanghua Depression, located in the central part of the Bohai Basin was conducted employing four sets of planar sandbox experimental models with different extension directions. Only experimental results of the model with N-S extension show good structural similarity with the depression. The results also indicate that complex variations of fault strike in a rift basin are not necessarily the results of complex kinematic mechanisms or polyphase deformation. Based on comparison of experimental results with the actual structures and the good structural similarity between Huanghua Depression and the whole Bohai Basin, it is concluded that the Bohai Basin was formed by the N-S extension. The strike slip deformation along the NNE-trending border faults of the basin resulted from the N-S extension and played the role of lateral transformation for the N-S extension. In addition, according to the apparent geometrical and kinematic similarities among the Bohai Basin and other Meso-Cenozoic extensional basins located along the eastern margin of the Eurasian Plate, it is proposed that: (1) this "N-S extension" model provides a better kinematic interpretation for the formation of Bohai Basin and the other adjacent basins located along the eastern margin of the Eurasian Plate; and (2) the N-S extension was probably the effect of the "slab window" formed by the subduction of the nearly E-W trending oceanic ridge between the Kula and Pacific Plates. The "slab window" effect can also provide reasonable explanations for the phenomena that initial rifting ages of basins become progressively younger westwards along the eastern margin of the Eurasian Plate

  4. Effect of Development of Caofeidian Harbor Area in Bohai Bay on Hydrodynamic Sediment Environment

    Institute of Scientific and Technical Information of China (English)

    LU Yong-jun; ZUO Li-qin; JI Rong-yao; XU Xiao; HUANG Jian-wei

    2008-01-01

    Based on the characteristics of waves, tidal currents, sediment and seabed evolution in the Caofeidian sea area in the Bohai Bay, a 2D sediment mathematical model of waves and tidal currents is employed to study the development schemes of the harbor. Verification of spring and neap tidal currents and sediment in the winter and summer of 2006 shows that the calculated values of tidal stages as well as flow velocities, flow directions and sediment concentration of 15 synchronous vertical lines are in good agreement with the measured data. Also, deposition and erosion of the sea area in front of Caofeidian ore terminal induced by suspended load under tidal currents and waves are verified; it shows that the calculated values of depth of deposition and erosion as well as their distribution are close to the measured data. Furthermore, effects of reclamation scheme of island in front of the land behind Caofeidian harbor on the hydrodynamic environment are studied, including changes of flow velocities in the deep channels at the south side of Caofeidian foreland and Laolonggou and in various harbor basins, as well as changes of deposition and erosion of seabed induced by the project.

  5. Anthropogenic Pb input into Bohai Bay, China: Evidence from stable Pb isotopic compositions in sediments

    Science.gov (United States)

    Hu, Ningjing; Huang, Peng

    2016-04-01

    Anthropogenic Pb input into Bohai Bay, China: Evidence from stable Pb isotopic compositions in sediments Hu Ning-jinga, Huang Pengb,, Liu Ji-huaa, a First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China b Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China To investigate the source of Pb within Bohai Bay, Pb concentrations and Pb isotopic compositions (204Pb, 206Pb, 207Pb, and 208Pb) of surface sediments in this area were determined. The Pb concentration in this bay varied widely from 6.9 to 39.2 μg/g (average: 21.8 ± 7.8 μg/g), and the Pb isotopic compositions ranged from 0.8338 to 0.8864 (average: 2.0997 ± 0.0180) for 208Pb/206Pb and from 2.0797 to 2.1531 (average: 0.8477 ± 0.0135) for 207Pb/206Pb, presenting in three distinct clusters. The Pb isotopic ratios of sediments from the northeastern (NE zone) and northwestern (NW zone) coastal areas were significantly influenced by anthropogenic sources such as coal combustion and automobile emission. In sediments from the central and southern Bohai Bay (C-S zone); however, Pb mainly originated from the Yellow River catchment, as a result of lithogenic sediment (from rock weathering) accumulation. The Pb isotopic ratios further indicate that, apart from riverine inputs, the neighboring large-scale ports and aerosols significantly contributed to the anthropogenic Pb contained in these sediments. Pb contamination in the Haihe and Luanhe river mouths as well as in the regions near ports is also suggested from anthropogenic enrichment factors. As cities and ports continue to develop around Bohai Bay, a long-term extensive sewage monitoring program is highly recommended.

  6. Statistical Analysis and Prediction of the Concentration of Harmful Algae in Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    WANG Hongli; FENG Jianfeng; LI Shengpeng; SHEN Fei

    2005-01-01

    Based on the data of phytoplankton concentration and environmental factors in Bohai Bay from May to September in 2003, the relationship between environmental factors and phytoplankton biomass was analyzed. By analysis of variance, the weather condition was found to have no direct relation with phytoplankton biomass. Correlation coefficients showed that temperature, pH value, the concentrations of silicate and nitrate exhibited linear relationship with phytoplankton biomass. With principal component analysis, pollution types which affected the abundance of phytoplankton included point sources such as municipal and industrial effluents, agricultural runoff and earth's surface water. Using multivariate stepwise regression method and taking the correlation analysis results into consideration, a multi-step regression equation was developed to predict the concentration of phytoplankton in September 2003. Combined results show that temperature, pH value, the concentrations of silicate and nitrate are the critical ecological factors affecting the phytoplankton biomass in Bohai Bay.

  7. Heavy Metals Pollution and Pb Isotopic Signatures in Surface Sediments Collected from Bohai Bay, North China

    OpenAIRE

    Bo Gao; Jin Lu; Hong Hao; Shuhua Yin; Xiao Yu; Qiwen Wang; Ke Sun

    2014-01-01

    To investigate the characteristics and potential sources of heavy metals pollution, surface sediments collected from Bohai Bay, North China, were analyzed for the selected metals (Cd, Cr, Cu, Ni, Pb, and Zn). The Geoaccumulation Index was used to assess the level of heavy metal pollution. Pb isotopic compositions in sediments were also measured to effectively identify the potential Pb sources. The results showed that the average concentrations of Cd, Cr, Cu, Ni, Pb, and Zn were 0.15, 79.73, 2...

  8. Research on Measurable Nonlinear Relationship Between Phytoplankton Biomass and Environmental Factors in Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    WANG Hongli; LI Shengpeng; FENG Jianfeng

    2005-01-01

    Based on the data of phytoplankton and environmental factors in the Bohai Bay, the dependence between the concentration of phytoplankton and environmental factors is analysed by linear correlation coefficient, rank correlation coefficient and Hoeffding test of independence .The result shows that wind-speed, air-pressure, surface temperature, field pH, salinity, DO, silicate and NO 3 have a great impact on the concentration of phytoplankton.

  9. Plio-Pleistocene evolution of Bohai Basin (East Asia): demise of Bohai Paleolake and transition to marine environment

    Science.gov (United States)

    Yi, Liang; Deng, Chenglong; Tian, Lizhu; Xu, Xingyong; Jiang, Xingyu; Qiang, Xiaoke; Qin, Huafeng; Ge, Junyi; Chen, Guangquan; Su, Qiao; Chen, Yanping; Shi, Xuefa; Xie, Qiang; Yu, Hongjun; Zhu, Rixiang

    2016-01-01

    The Bohai Basin was transformed to an inner shelf sea hundreds of thousands years ago. This youngest land-sea transition participated in the significant modification of the distribution of fresh water, sediment fluxes and climate in East Asia, and played an important role in the origin of the Asian marginal seas. Here we present the results of a magnetostratigraphic investigation and propose a conceptual model for the land-sea transition. Our findings indicate that the transition probably started several million years ago, from a fluvial system during the late Miocene and early Pliocene, to a lacustrine environment between the late Pliocene and Middle Pleistocene, and finally to a marine system in the late Pleistocene. Comparison of our results with previous research suggests that the Bohai Paleolake was initiated from the late Pliocene, was fully developed prior to ~1.0 Ma, and terminated around the late Middle Pleistocene. The Miaodao Islands formed the eastern “barrier” of the basin and since the Pliocene or earlier they played a significant role in blocking the lake water and sediments. They deformed from ~1.0 Ma, subsided significantly at ~0.3 Ma and completely by ~0.1 Ma, resulting in the maturation of the basin as an inner shelf sea. PMID:27384419

  10. Plio-Pleistocene evolution of Bohai Basin (East Asia): demise of Bohai Paleolake and transition to marine environment

    Science.gov (United States)

    Yi, Liang; Deng, Chenglong; Tian, Lizhu; Xu, Xingyong; Jiang, Xingyu; Qiang, Xiaoke; Qin, Huafeng; Ge, Junyi; Chen, Guangquan; Su, Qiao; Chen, Yanping; Shi, Xuefa; Xie, Qiang; Yu, Hongjun; Zhu, Rixiang

    2016-07-01

    The Bohai Basin was transformed to an inner shelf sea hundreds of thousands years ago. This youngest land-sea transition participated in the significant modification of the distribution of fresh water, sediment fluxes and climate in East Asia, and played an important role in the origin of the Asian marginal seas. Here we present the results of a magnetostratigraphic investigation and propose a conceptual model for the land-sea transition. Our findings indicate that the transition probably started several million years ago, from a fluvial system during the late Miocene and early Pliocene, to a lacustrine environment between the late Pliocene and Middle Pleistocene, and finally to a marine system in the late Pleistocene. Comparison of our results with previous research suggests that the Bohai Paleolake was initiated from the late Pliocene, was fully developed prior to ~1.0 Ma, and terminated around the late Middle Pleistocene. The Miaodao Islands formed the eastern “barrier” of the basin and since the Pliocene or earlier they played a significant role in blocking the lake water and sediments. They deformed from ~1.0 Ma, subsided significantly at ~0.3 Ma and completely by ~0.1 Ma, resulting in the maturation of the basin as an inner shelf sea.

  11. Heavy aerosol loading over the Bohai Bay as revealed by ground and satellite remote sensing

    Science.gov (United States)

    Zhang, Jinqiang; Chen, Jing; Xia, Xiangao; Che, Huizheng; Fan, Xuehua; Xie, Yiyang; Han, Zhiwei; Chen, Hongbin; Lu, Daren

    2016-01-01

    Heavy aerosol loading over the Bohai Bay, the innermost gulf of the Yellow Sea, was often recorded by the satellite observations. In order to understand aerosol optical properties and potential causes for the high aerosol loading there, a Cimel sunphotometer station (BH) was established on an offshore platform over the Bay for the first time in June 2012. The aerosol optical properties between July 2012 and July 2013 were employed to validate the satellite retrievals and to characterize temporal variability of aerosol optical properties. In particular, aerosol optical properties at BH were compared with those at Beijing (BJ), an urban station of the North China Plain (NCP), to discuss their potential difference during the same months of the same years. Mean aerosol optical depth at 550 nm (AOD) retrieved from the Moderate Resolution Imaging Spectroradiometer (MODIS) measurements over the Bohai Bay was 0.79 ± 0.68 during 2004-2013, that even exceeded value over the NCP (0.50 ± 0.57). This fact was supported by the comparison of ground-based remote sensing AODs at BH and BJ. The annual mean Cimel AOD at BH was 0.76 ± 0.62, which was larger than that at BJ (0.64 ± 0.52). The MODIS AOD difference between the Bohai Bay and the NCP was 0.29, being more than two times larger than the Cimel AOD difference between BH and BJ (0.12). This strongly implied that the MODIS retrievals had significant biases over the Bohai Bay that was likely due to sediment in the water and also sea ice in winter. A distinct seasonal variation of AOD was revealed over ocean. The maxima Cimel AOD was observed in summer (1.02 ± 0.75), which was followed by spring (0.86 ± 0.61), autumn (0.54 ± 0.41), and winter (0.39 ± 0.24); this was in good agreement with that over the NCP. High AOD over the Bohai Bay was associated with the heavy exhaust emissions from the ships across the Bay and transport of aerosols from the NCP. Furthermore, a much strong hygroscopic growth of fine mode aerosols over

  12. Evaluation of estimation methods for meiofaunal biomass from a meiofaunal survey in Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    张青田; 王新华; 胡桂坤

    2010-01-01

    Studies in the coastal area of Bohai Bay,China,from July 2006 to October 2007,suggest that the method of meiofaunal biomass estimation affected the meiofaunal analysis.Conventional estimation methods that use a unique mean individual weight value for nematodes to calculate total biomass may cause deviation of the results.A modified estimation method,named the Subsection Count Method (SCM),was also used to calculate meiofaunal biomass.This entails only a slight increase in workload but generates results of g...

  13. The Sedimentary Characteristics and Formation Mechanism of Shell Ridges Along the Southwest Coast of Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    LIU Zhijie; ZHUANG Zhenye; HAN Deliang; QI Xingfen

    2005-01-01

    The present paper studies the sedimentary characteristics and mechanism of the shell ridges on the southwestern coast of Bohai Bay, which are the largest and have the highest shell (or shell fragment) content in the world. These shell ridges are composed of two sedimentary subfacies: the ridge subfacies and the ridge infill subfacies with different inner textures and sedimentary structures. The ridge subfacies primarily consists of fresh shells and/or shell fragments with parallel beddings and high-angle oblique beddings. The ridge infill subfacies consists of finer shell fragments and silty sand with parallel beddings oblique to land. The evolution of the shell ridge is controlled by the accumulation of substantial shell material,the relative slow erosion of shoreline, storm waves, winds and the shift of river routes. Wind tunnel tests indicate that the critical movement velocity of shell is lower than that of quartz sand of the same grain size. Deltaic progradation alternates with shell ridge growth. While the Yellow River empties into the sea through this area, accompanied by deltaic progradating, the shell material is scarce, which is unfavorable to the growth of the shell ridge. Conversely, erosion occurs along an abandoned delta coast where a shell ridge may develop, e.g. the shell ridge on the southwest of Bohai Bay.

  14. Heavy metal pollution in tidal zones of Bohai Bay using the dated sediment cores

    Institute of Scientific and Technical Information of China (English)

    QIN Yan-wen; MENG Wei; ZHENG Bing-hui; SU Yi-bin

    2006-01-01

    Three sediment cores were collected in November 2003 from Dagu estuary to Qikou estuary. The main polluted heavy metals in the sediment of tidal zones for the Bohai Bay have been found by analyzing the relationship among the contents of heavy metals, the contents of geochemical elements (Fe, Al and Mn) and the size of grain. The dominating contaminative elements in tidal sediments of Bohai Bay are Pb, Zn and Cd. Their contents are higher than the corresponding upper limit of environmental background values and they have very faint correlation with the corresponding contents of geochemical elements and the size of grain, indicating the anthropogenic enrichment. Especially, the preliminary study on the pollution sources and the history of heavy metals in the Dagu estuary has been done using the dated results. The contamination by Zn and Cd also started in the middle 1950s, while the contamination by Pb appeared in the early 1940s. The pollution by Zn and Cd mainly originate from sewage discharge, while the pollution by Pb has many sources, like atmosphere deposition and industrial discharge.

  15. Study and review on crust-mantle velocity structure in Bohai Bay and its vicinity

    Institute of Scientific and Technical Information of China (English)

    张成科; 张先康; 赵金仁; 任青芳; 张建狮; 海燕

    2002-01-01

    Observational data from some of the 10-odd deep seismic sounding profiles in Bohai Bay and its adjacent areas were processed with the methods of two-dimensional ray tracing, travel-time fitting and synthetic seismogram. The crust and upper-mantle velocity structure model in this area was built. The results show that the crust and upper mantle structures present obvious lateral and vertical inhomogeneity. The upper mantle uplifts near Yongqing of northeast Jizhong depression, in Bohai Bay of Huanghua depression and near Kenli of Jiyang depression, where crustal depths are about 31 km, 28 km and 29 km, respectively. According to the dynamic and kinetic characteristics of seismic waves as well as the seismic interfaces and velocity contour undulation in the 2-D velocity structure model, three deep crustal fault zones are inferred in the area. Low velocity (5.90~6.10 km/s) layers (bodies) exist on one or two sides of these deep crustal fault zones.

  16. Evaluation of carbon dioxide storage potential for the Bohai Basin, North-East China

    OpenAIRE

    Vincent, Ceri; Poulsen, Niels E.; Rongshu, Zeng; Shifeng, Dai; Mingyuan, Li; Guosheng, Ding

    2011-01-01

    The storage potential of selected sites within the Bohai Basin was assessed for the COACH project. The Gangdong oilfield is considered to have a small potential storage capacity (23 Mt) and to be possibly suitable for an enhanced oil recovery or small-scale storage pilot rather than large-scale storage. The Shengli oilfield province is considered to have a great potential storage capacity (472 Mt in eight selected fields), however, these fields, like those of the Gangdong oilfield province, a...

  17. Occurrence and distribution of antibiotic resistance genes in the coastal area of the Bohai Bay, China.

    Science.gov (United States)

    Niu, Zhi-Guang; Zhang, Kai; Zhang, Ying

    2016-06-15

    Considering the abuse of antibiotics worldwide, we investigated the abundance of three classes of antibiotic resistance genes (ARGs) and the concentrations of corresponding antibiotics in water and sediments of Bohai Bay. The results showed that sulI and sulII were detected in all samples, and their abundance range was 10(-5)-10(-2)/16S gene copies. The abundance of tetM and ermB were relatively higher than the other genes of tet-ARGs and erm-ARGs. Sulfonamides were the most prevalent antibiotics, and the concentrations of antibiotic in sediments were higher than those in water. The correlation analysis revealed that antibiotics had pertinence with corresponding ARGs, indicating that antibiotics play an important role in the creation and transfer of ARGs. The results of regression analysis indicated that the propagation and maintenance of sulI and sulII were facilitated by class I integrons.

  18. Occurrence and distribution of antibiotic resistance genes in the coastal area of the Bohai Bay, China.

    Science.gov (United States)

    Niu, Zhi-Guang; Zhang, Kai; Zhang, Ying

    2016-06-15

    Considering the abuse of antibiotics worldwide, we investigated the abundance of three classes of antibiotic resistance genes (ARGs) and the concentrations of corresponding antibiotics in water and sediments of Bohai Bay. The results showed that sulI and sulII were detected in all samples, and their abundance range was 10(-5)-10(-2)/16S gene copies. The abundance of tetM and ermB were relatively higher than the other genes of tet-ARGs and erm-ARGs. Sulfonamides were the most prevalent antibiotics, and the concentrations of antibiotic in sediments were higher than those in water. The correlation analysis revealed that antibiotics had pertinence with corresponding ARGs, indicating that antibiotics play an important role in the creation and transfer of ARGs. The results of regression analysis indicated that the propagation and maintenance of sulI and sulII were facilitated by class I integrons. PMID:27107623

  19. Influence of early diagenesis on the vertical distribution of metal forms in sediments of Bohai Bay, China.

    Science.gov (United States)

    Lu, Xueqiang; Zhang, Yan; Liu, Honglei; Xing, Meinan; Shao, Xiaolong; Zhao, Feng; Li, Xiaojuan; Liu, Qiongqiong; Yu, Dan; Yuan, Xuezhu; Yuan, Min

    2014-11-15

    The influence of early diagenesis on the vertical distribution of metal forms in the sediments of Bohai Bay was discussed in this paper. The results showed that the concentrations were: Al > Fe ≈ Ca > Mn > Cr > Zn > Cu > Pb > Cd. In vertical distribution, the forms of Cr and Pb were stable from the top to the bottom. However, the exchangeable forms and acid-extracted forms of Cd, Cu and Zn presented an obvious declining trend. The metals would be transformed to more stable forms during the early-diagenesis process. Further analysis found that early diagenesis can change the sedimentary environment, affecting pH, oxidation-reduction potential (ORP), total dissolved solid (TDS) and the structure of organic matter (OM), all main factors influencing metal forms in the sediments of Bohai Bay.

  20. Sediment Quality of the SW Coastal Laizhou Bay, Bohai Sea, China: A Comprehensive Assessment Based on the Analysis of Heavy Metals

    OpenAIRE

    Gao, Xuelu; Zhuang, Wen; Chen, Chen-Tung Arthur; Zhang, Yong

    2015-01-01

    Historically, the Bohai Sea is one of the most important fishing grounds in China. Yet, surrounded by one of the biggest economic rims of China, its ecological functions have been declining rapidly in recent two decades under the heavy anthropogenic impacts. The Laizhou Bay is the smallest one of the three main bays in the Bohai Sea. Owing to the rich brine deposits, chemical industries using brine as raw materials are booming in the southern coast of the Laizhou Bay, the scale of which ranks...

  1. Zinc and copper bioaccumulation in fish from Laizhou Bay, the Bohai Sea

    Science.gov (United States)

    Liu, Jinhu; Cao, Liang; Huang, Wei; Zhang, Chuantao; Dou, Shuozeng

    2014-05-01

    Zinc (Zn) and copper (Cu) concentrations were determined in the tissues (muscle, stomach, liver, gills, skin, and gonads) of five commercial fish species (mullet Liza haematocheilus, flathead Platycephalus indicus, mackerel Scomberomorus niphonius, silver pomfret Pampus argenteus, and sea bass Lateolabrax japonicus) from Laizhou Bay in the Bohai Sea. Metal bioaccumulation was highest in the metabolically active tissues of the gonads and liver. Bioconcentration factors for Zn were higher in all tissues (gonads 44.35, stomach 7.73, gills 7.72, liver 5.61, skin 4.88, and muscle 1.63) than the corresponding values for Cu (gonads 3.50, stomach 3.00, gills 1.60, liver 5.43, skin 1.50, and muscle 0.93). Mackerel tissues accumulated metal to higher concentrations than did other fish species, but bioaccumulation levels were not significantly correlated with the trophic levels of the fish. Zn and Cu concentrations in the tissues were generally negatively correlated with fish length, except for a few tissues of sea bass. Risk assessment based on national and international permissible limits and provisional tolerances for weekly intake of Zn and Cu revealed that the concentrations of these two metals in muscle were relatively low and would not pose hazards to human health.

  2. Distribution of favorable lacustrine carbonate reservoirs: A case from the Upper Es4 of Zhanhua Sag, Bohai Bay Basin%湖相碳酸盐岩有利储集层分布——以渤海湾盆地沾化凹陷沙四上亚段为例

    Institute of Scientific and Technical Information of China (English)

    彭传圣

    2011-01-01

    Based on core thin sections, logging and seismic data, the distribution of favorable lacustrine carbonate reservoirs is predicted in the upper Efu of the Zhanhua Sag, Bohai Bay Basin. In the upper Es4 of the Zhanhua Sag, four categories of carbonates are developed, I.e. Bioclastic limestones (dolomites), intraclastic limestones (dolomites), arenaceous limestones (dolomites) and argillaceous limestones (dolomites). With core calibrated logs, the electrical characteristics interpretation criteria for various carbonates are established, and the lithofacies sequences of the exploratory well are reconstructed. According to overlying pattern of high-frequency cycles, the short-term cycles of bioherm, carbonate bank and semi-deep lake are divided, and high resolution isochronous formation framework is built. On the basis of the facies characteristics of well tie sections and palaeo-landform background, the carbonate depositional model is established, namely, the reef and bank carbonates are deposited from the largest expansion period to the stable period of lake basin, bank carbonates* are mainly distributed on the upper side of synsedimentary faults on the gentle slope or deposited in fault-step lowland on the steep slope while the reef carbonates mainly on fault-step highland on the steep slope. Favorable reservoir types include reef bioclastic limestone (dolomite), bank bioclastic limestone (dolomite), intraclastic limestone (dolomite) and arenaceous limestone. It is possible to predict the distribution of favorable reservoirs according to the depositional model, palaeo-landform analysis and seismic amplitude attributes.%运用岩心薄片、测井、地震等资料和技术手段,预测渤海湾盆地沾化凹陷沙四上亚段湖相碳酸盐岩有利储集层分布.研究表明,沾化凹陷沙四上亚段发育生物碎屑灰/云岩类、内碎屑灰/云岩类、砂质灰/云岩类、泥灰/云岩类等4大类碳酸盐岩.用岩心刻度测井,分区建立了不同

  3. Physical modeling of petroleum downward migration:A case study of western Chezhen Sag, Jiyang Depression, Bohai Bay Basin%渤海湾盆地济阳坳陷车镇凹陷西部深层油气倒灌的物理模拟实验

    Institute of Scientific and Technical Information of China (English)

    郝雪峰; 单亦先; 劳海港

    2013-01-01

    According to the theory of hydrocarbon downward migration, based on seismology, geochemistry, well drilling and logging, it is discussed in this paper the accumulation mechanism of petroleum downward migration in the western Chezhen Sag, the Jiyang Depression, the Bohai Bay Basin. The main pathways of hydrocarbon downward migration include factures or micro cracks in the process of secondary migration, and the formation process of hydrocarbon downward migration is reproduced by experimental simulation. Source rocks in the middle and lower subsections of the 3rd member of the Shahejie Formation have good genetic relationships with oil sands from the upper subsection of the 4th member of the Shahejie Formation, and reservoirs discovered in the upper subsection of the 4th member of the Shahejie Formation are buried deeper than the bottom boundary of source rocks from the 3rd member of the Shahejie Formation. In the lower subsection of the 3rd member of the Shahejie Formation, pressure coefficients range from 1. 0 to 1. 4, and decrease both upwards and downwards, providing force for petroleum downward migration. Cracks and fractures break the mudstone interlayers between the bottom boundary of source rocks from the 3rd member of the Shahejie Formation and the top surface of the 4th member of the Shahejie Formation. As a result, source rocks and reservoirs are connected.%  以油气倒灌理论为指导,综合利用地震、地化、钻井、测井等资料,研究了渤海湾盆地济阳坳陷车镇凹陷西部油气倒灌的成藏机理.通过实验模拟油气在二次运移过程中以断裂(或微裂缝)为倒灌通道的过程,再现油气倒灌的形成过程.研究表明, Es3(中-下)亚段烃源岩与 Es4(上)亚段油砂具有较好的亲缘关系,且 Es4(上)亚段发现的油藏埋深大于 Es3烃源岩底界埋藏深度;Es3(下)地层压力系数在1.0~1.4之间,向上和向下压力系数均逐渐减小,是油气倒灌的动

  4. Geochemistry of Clayey Aquitard Pore Water as Archive of Paleo-Environment, Western Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    Jing Li; Xing Liang; Menggui Jin; Guoqiang Xiao; Jishan He; Yandong Pei

    2015-01-01

    The record of paleo-environment in clayey aquitard pore water is much more effective relative to aquifer groundwater owing to the low permeability of clayey aquitard. Oxygen-18 (18O), deuterium (D), and chemical patterns were determined in pore water samples extracted from two 500 m depth boreholes, G1 and G2, in western Bohai Bay, China. Shallow pore water samples (depth<102 m) are saline water, with the TDS (total dissolved solids) of 3.69–30.75 g/L, and deeper ones (depth=102–500 m) are fresh water, with the TDS<1 g/L. Content of major ions (i.e., Cl-, Na+, K+, Mg2+, SO42-, Ca2+) is high in marine sediment pore water samples and gradually decrease towards to terre-strial sediment pore water, together with the Cl/Br and Sr/Ba ratios changing significantly in different sedimentary facies along the study profile, indicating that pore water may be paleo-sedimentary water and not replaced by modern water.δ18O profile and positive correlation betweenδ18O and Cl-of shal-low saline pore water indicated diffusion as the main transport mechanism, and distinguished four transgressive layers since Late Quaternary (i.e., Holocene marine unit, two Late Pleistocene marine units and Middle Pleistocene marine unit), further supporting the finding that pore water retained the feature of paleo-sedimentary water. Climate was identified as the main influence on the isotopic signa-ture of aquitard pore water and four climate periods were determined byδ18O profile.

  5. Diversity and distribution of bacterial community in the coastal sediments of Bohai Bay, China

    Institute of Scientific and Technical Information of China (English)

    WANG Liping; ZHENG Binghui; LEI Kun

    2015-01-01

    In order to understand the diversity and distribution of the bacterial community in the coastal sediment of the Bohai Bay, China, high-throughput barcoded pyrosequencing of the 16S rRNA gene was used. Metagenomic DNA was extracted from the sediment samples, and was sequenced using a 454 GS FLX Titanium system. At 97%similarity, the sequences were assigned to 22 884 operational taxonomic units (OTUs) which belonged to 41 phyla, 84 classes, 268 genera and 789 species. At the different taxonomic levels, both the dominants and their distribution varied significantly among the six coastal sediments. Proteobacteria was the first dominant phylum across all the six coastal sediments, representing 57.52%, 60.66%, 45.10%, 60.92%, 56.63% and 56.59%, respectively. Bacteroidetes was the second dominant phylum at Stas S1, S2 and S4, while Chloroflexi was the second dominant phylum at Stas S3, S5 and S6. At class level,γ-Proteobacteria was the first dominant class at Stas S1, S2, S4 and S6, whileδ-Proteobacteria became the first dominant class at Stas S3 and S5. In addition, a large proportion of unclassified representatives have distributed at the different taxonomic levels. Canonical correspondence analysis (CCA) results indicated that the sediment texture, water depth (D), dissolved oxygen (DO), total nitrogen (TN) and nine EPA priority control polycyclic aromatic hydrocarbons (PAHs) including naphthalene, acenaphthylene, acenaphthene, fluorine, phenanthrene, fluoranthene, pyrene, benzo[a]anthracene and indeno[1,2,3-cd]pyrene were the important factors in regulating the bacterial community composition. Those results are very important to further understand the roles of bacterial community in the coastal biogeochemical cycles.

  6. Determination of trophic relationships within a Bohai Bay food web using stable δ15N and δ13C analysis

    Institute of Scientific and Technical Information of China (English)

    WAN Yi; HU Jianying; AN Lihui; AN Wei; YANG Min; Itoh Mitsuaki; Hattori Tatsuya; TAO Shu

    2005-01-01

    This study measured stable carbon and nitrogen isotope ratios in phytoplankton, zooplankton, five invertebrates species, eight fishes species and three seabirds species collected in Bohai Bay. δ13C ranged from -25.38‰ to -11.08‰ showing a relative low enrichment in the food web from Bohai Bay. The mean δ13C of mullet is higher than that of other organisms, and this might be due to that mullet is migration fish and feeds mainly on inshore sources. δ15N ranged from 4.08‰ to 13.98‰, and showed a step-wise enrichment with trophic level of 3.8‰. The δ15N enrichment factor was used to construct an isotopic food web model to establish trophic relationships within this marine food web. According to this model, exact trophic levels of all organisms were estimated as 1.46-2.10, 1.91-3.32, 2.55-4.23 and 2.98-4.28 for plankton, invertebrates, fishes, and seabirds.

  7. Concentration distribution and potential health risk of heavy metals in Mactra veneriformis from Bohai Bay, China

    International Nuclear Information System (INIS)

    Highlights: • Mn was dominant in the heavy metals, followed by Zn, and Pb was the lowest. • THQs of Co were the highest at three sections and the others were less than 1. • Heavy metal concentration in clam was affected by pollution sources, and itself. • Consumer should be aware of their health risks associated with the consuming clam. - Abstract: To investigate the pollution level and evaluate the potential health risks of heavy metals, the concentrations of chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), molybdenum (Mo), cadmium (Cd), antimony (Sb), and lead (Pb) were determined by inductively coupled plasma-mass spectrometry (ICP-MS) in 198 clams (Mactra veneriformis) collected from 11 sites of the Bohai Bay. The results showed that heavy metal concentrations in the clams were different at different sites (p < 0.05). Mn was dominant with a percentage of 22.08–77.03% in heavy metals, followed by Zn with 12.66–57.11%, and the concentration of Pb was the lowest with 0.45–1.04%. The potential health risk to consumers was evaluated by the target hazard quotient (THQ) and the maximum daily consumption rate (CRmax). The results indicated that the THQs of Co were the highest with the values of 1.125, 1.665, and 1.144 at three sections; the values of other individual metals were <1, which indicated that consumption of clams from the study areas caused health risks due to Co. Moreover, the CRmax values also indicated the potential health risk caused by Co in clams consumed in this area. Pearson correlation analysis and principal component analysis (PCA) indicated that there were significantly positive or negative correlations between the heavy metals (p < 0.05), and the studied metals were divided into four groups. The results indicated that the concentrations of heavy metals in clams were affected not only by pollution sources but also by the characteristics of clams that could absorb

  8. Biodegradation of marine crude oil pollution using a salt-tolerant bacterial consortium isolated from Bohai Bay, China.

    Science.gov (United States)

    Li, Xinfei; Zhao, Lin; Adam, Mohamed

    2016-04-15

    This study aims at constructing an efficient bacterial consortium to biodegrade crude oil spilled in China's Bohai Sea. In this study, TCOB-1 (Ochrobactrum), TCOB-2 (Brevundimonas), TCOB-3 (Brevundimonas), TCOB-4 (Bacillus) and TCOB-5 (Castellaniella) were isolated from Bohai Bay. Through the analysis of hydrocarbon biodegradation, TCOB-4 was found to biodegrade more middle-chain n-alkanes (from C17 to C23) and long-chain n-alkanes (C31-C36). TCOB-5 capable to degrade more n-alkanes including C24-C30 and aromatics. On the basis of complementary advantages, TCOB-4 and TCOB-5 were chosen to construct a consortium which was capable of degrading about 51.87% of crude oil (2% w/v) after 1week of incubation in saline MSM (3% NaCl). It is more efficient compared with single strain. In order to biodegrade crude oil, the construction of bacterial consortia is essential and the principle of complementary advantages could reduce competition between microbes.

  9. 渤海湾盆地歧口凹陷古近系沙一段物源—沉积体系重建%Reconstruction of Provenance-Sedimentary System of the First Member of the Paleogene Shahejie Formation in the Qikou Sag,Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    吕琳; 焦养泉; 吴立群; 鲁超; 荣辉; 汪小妹

    2012-01-01

    采用布格重力异常手段宏观地区分物源区和沉积区,根据重矿物特征分析物源区位置及影响范围,依据地震反射特征识别物源运移方向,通过砂分散体系精细分析和表征物源—沉积体系特征,并利用岩石地球化学资料进一步佐证物源—沉积体系分析。综合研究表明,渤海湾盆地歧口凹陷沙一段时期存在五个物源区,分别为葛沽物源、小站物源、增福台物源、钱圈物源和北大港潜山物源。葛沽物源为板桥次凹提供沉积物,且沉积物主体呈两支向歧口主凹进一步推进;小站物源、增福台物源和钱圈物源影响范围较小,均呈两支进入板桥次凹;北大港潜山物源为歧北次凹提供沉积物,向马棚口和高尘头地区推进时物源频繁分叉。综合岩芯、录井、测井和古生物等沉积成因标志,认为板桥次凹发育扇三角洲沉积体系,歧口主凹和歧北次凹发育深湖浊流体系。%Accoding to the characteristics of the Bouguer gravity anomalies,the source and deposition areas were macroscopically distinguished in this paper.Based on the characteristics of heavy mineral,the location and extent of the source areas were described.In addition,the direction of the sources were determined on the basis of seismic reflection characteristics.Furthermore,the characteristics of provenance-sedimentary system were finely pictured by the distribution of sandbody,and could be further verified through geochemical characteristics.Different ways exerted respective superiority,and various means revised each other,the provenance-sedimentary system of the first member of the Paleogene Shahejie Formation in the Qikou sag of the Bohai bay basin was reconstructed by these ways.The results suggested that,there were five sources in the first member of Shahejie Formation in the Qikou sag,that were Gegu source,Xiaozhan source,Zengfutai source,Qianquan source and Beidagang buried hill source.The Gegu source was

  10. Near surface velocity and Qs structure of the Quaternary sediment in Bohai basin, China

    Institute of Scientific and Technical Information of China (English)

    Jiajun Chong; Sidao Ni

    2009-01-01

    Heavily populated by Beijing and Tianjin cities, Bohai basin is a seismically active Cenozoic basin suffering from huge lost by devastating earthquakes, such as Tangshan earthquake. The attenuation (QP and QS) of the surficial Quaternary sediment has not been studied at natural seismic frequency (l-10Hz), which is crucial to earthquake hazards study. Borehole seismic records of micro earthquake provide us a good way to study the velocity and attenuation of the surficial structure (0-500 m). We found that there are two pulses well separated with simple waveforms on borehole seismic records from the 2006 MW4.9 Wen'an earthquake sequence. Then we performed waveform modeling with generalized ray theory (GRT) to confirm that the two pulses are direct wave and surface reflected wave, and found that the average vP and vS of the top 300 m in this region are about 1.8km/s and 0.42 km/s, leading to high vP/vS ratio of 4.3. We also modeled surface reflected wave with propagating matrix method to constrain QS and the near surface velocity structure. Our modeling indicates that QS is at least 30, or probably up to 100, much larger than the typically assumed extremely low Q(~10), but consistent with QS modeling in Mississippi embayment. Also, the velocity gradient just beneath the free surface (0-50 m) is very large and velocity increases gradually at larger depth. Our modeling demonstrates the importance of borehole seismic records in resolving shallow velocity and attenuation structure, and hence may help in earthquake hazard simulation.

  11. Assessing the benthic quality status of the Bohai Bay (China) with proposed modifications of M-AMBI

    Institute of Scientific and Technical Information of China (English)

    CAI Wenqian; BORJA Angel; LIN Kuixuan; ZHU Yanzhong; ZHOU Juan; LIU Lusan

    2015-01-01

    Multivariate AZTI’s Marine Biotic Index (M-AMBI) was designed to indicate the ecological status of European coastal areas. Based upon samples collected from 2009 to 2012 in the Bohai Bay, we have tested the response of variations of M-AMBI, using biomass (M-BAMBI) in the calculations, with different transformations of the raw data. The results showed that the ecological quality of most areas in the study indicated by M-AMBI was from moderate to bad status with the worse status in the coastal areas, especially around the estuaries, harbors and outfalls, and better status in the offshore areas except the area close to oil platforms or disposal sites. Despite large variations in nature of the input data, all variations of M-AMBI gave similar spatial and temporal distribution patterns of the ecological status within the bay, and showed high correlation between them. The agreement of new ecological status obtained from all M-AMBI variations, which were calculated according to linear regression, was almost perfect. The benthic quality, assessed using different input data, could be related to human pressures in the bay, such as water discharges, land reclamation, dredged sediment and drilling cuts disposal sites. It seems that M-BAMBI were more effective than M-NABMI (M-AMBI calculated using abundance data) in indicating human pressures of the Bay. Finally, indices calculated with more severe transformations, such as presence/absence data, could not indicate the higher density of human pressures in the coastal areas of the north part of our study area, but those calculated using mild transformation (i.e., square root) did.

  12. Development Strategies for Achieving High Production with Fewer Wells in Conventional Offshore Heavy Oil Fields in Bohai Bay, China

    Institute of Scientific and Technical Information of China (English)

    Fu Xiang; Li Xiangfang; Kang Xiaodong

    2006-01-01

    Development strategy for heavy-oil reservoirs is one of the important research interests in China National Offshore Oil Corp. (CNOOC) that plans a highly effective development for heavy oil fields in multilayered fluvial reservoirs because of their significant influence on marine oil and even on China's petroleum production. The characteristics analysis of multilayered fluvial reservoirs in the heavy oil fields in Bohai Bay indicates that large amounts of oil were trapped in the channel, point bar and channel bar sands. The reserves distribution of 8 oilfields illustrates that the reserves trapped in the main sands, which is 20%-40% of all of the sand bodies, account for 70%-90% of total reserves of the heavy oil fields. The cumulative production from high productivity wells (50% of the total wells) was 75%-90% of the production of the overall oilfield, while only 3%-10% of the total production was from the low productivity wells (30% of the total wells). And the high productivity wells were drilled in the sands with high reserves abundance. Based on the above information the development strategy was proposed, which includes reserves production planning, selection of well configuration, productivity design, and development modification at different stages.

  13. Trophic magnification of polybrominated diphenyl ethers in the marine food web from coastal area of Bohai Bay, North China.

    Science.gov (United States)

    Shao, Mihua; Tao, Ping; Wang, Man; Jia, Hongliang; Li, Yi-Fan

    2016-06-01

    Trophic transfer of polybrominated diphenyl ethers (PBDEs) in aquatic ecosystems is an important criterion for assessing their environmental risk. This study analyzed 13 PBDEs in marine organisms collected from coastal area of Bohai Bay, China. The concentrations of total PBDEs (Σ13PBDEs) ranged from 12 ± 1.1 ng/g wet weight (ww) to 230 ± 54 ng/g ww depending on species. BDE-47 was the predominant compound, with a mean abundance of 20.21 ± 12.97% of total PBDEs. Stable isotopic ratios of carbon (δ(13)C) and nitrogen (δ(15)N) were analyzed to determine the food web structure and trophic level respectively. Trophic magnification factors (TMFs) of PBDEs were assessed as the slope of lipid equivalent concentrations regressed against trophic levels. Significant positive relationships were found for Σ13PBDEs and eight PBDE congeners (BDE-28, BDE-47, BDE-49, BDE-66, BDE-85, BDE-99, BDE-100 and BDE-154). Monte-Carlo simulations showed that the probabilities of TMF >1 were 100% for Σ13PBDEs, BDE-47, BDE-85, BDE-99 and BDE-100, 99% for DE-28, BDE-49, BDE-66 and BDE-154, 94% for BDE-153, and 35% for BDE-17.

  14. 渤海湾西岸的几道贝壳堤%A Few of Barrier Sand-bars on the West Coast of Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    岳军; Dongyue; 张宝华; 耿秀山; 刘雪松; 赵希涛; 牟林; 张百鸣; 韩芳

    2012-01-01

    There are 6 Barrier Sand-bars are outcropped or buried on the west coast of Bohai Bay. Based on the geological survey, it is found that the plane distribution features texture of the Barrier Sand-bars, which are from the old to the new are roughly parallel with the coast along the west coast of Bohai Bay (from the coast to the sea). The distribution of the Barrier Sand-bars can be divided into two kinds, one is from the new to the old, and the other one is from the old to the new. In this paper, the division of the Barrier Sand-bars from I (old) to VI (new) by using the latter one. Through the description of the material composition and the accumulation characteristics to each barrier sand-bar (figure. 2 to figure. 7) , conducting the mathematical statistics for the geometrical morphological features (table 2), comparing analysis the formation age features and the division scheme (table 3), summing up the biological assemblages (table 1), the result reveal the occurrence, formation age and the tidal level change of the Barrier Sand-bars from I to VI (figure. 8). In the basis of the Barrier Sand-bars as a particular geological carrier, the author try to analysis and reveal the genetic mechanism in a macroscopic view, and consider that the generalized Bohai Sea is inland semi-lagoon or local sea in reality, (table. 4 figure. 9) Shangdong Miaodao Island and Liaodong Peninsula constitute barrier coast for Bohai Sea. After comparing analysis to massive data, the barrier coast is an only essential condition to form kebohe delta and beaked delta, both of which may be a possibility condition to form barrier bars (barrier island, barrier beach) or shell ridges. This result is just main genetic mechanism for the shell ridges.

  15. Formation mechanisms of heavy oils in the Liaohe Western Depression,Bohai Gulf Basin

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The Liaohe Oilfield in the Liaohe Western Depression of the Bohai Gulf Basin is the third-largest oil producing province and the largest heavy oil producing oilfield in China. A total of 65 oil samples,35 rock samples and 36 reservoir sandstone samples were collected and analyzed utilizing conventional geochemical and biogeochemical approaches to unravel the mechanisms of the formation of the heavy oils. Investigation of the oils with the lowest maturity compared with the oils in the Gaosheng and Niuxintuo oilfields indicates no apparent relation between the maturity and physical properties of the heavy oils. It is suggested that the heavy oil with primary origin is not likely the main mechanism re-sponsible for the majority of the heavy oils in the Liaohe Western Slope. The absence and/or depletion of n-alkanes etc.,with relatively low molecular weight and the occurrence of 25-norhopane series in the heavy oils as well as the relatively high acidity of the oils all suggest that the majority of the heavy oils once experienced secondary alteration. The fingerprints of the total scanning fluorescence (TSF) of the inner adsorbed hydrocarbons on the reservoir grains and the included hydrocarbons in fluid inclusions are similar to that of the normal oils in the area but are different from the outer adsorbed and reser-voired free oils at present,further indicating that most of the heavy oils are secondary in origin. Analyses of bacteria (microbes) in 7 oil samples indicate that anaerobic and hyperthermophilic Ar-chaeoglobus sp. are the dominant microbes relevant to oil biodegradation,which coincides with the shallow commercial gas reservoirs containing anaerobic bacteria derived gas in the Gaosheng and Leijia teotonic belts. The biodegradation most likely occurs at the water/oil interface,where the forma-tion water is essential for microbe removal and nutrient transportation. We think that biodegradation,water washing and oxidization are interrelated and are the main

  16. Simulation of groundwater-seawater interaction in the coastal surficial aquifer in Bohai Bay, Tianjin, China

    Science.gov (United States)

    Yi, Lixin; Ma, Bo; Liu, Lingling; Tang, Guoqiang; Wang, Tianyu

    2016-08-01

    This paper quantitatively investigates groundwater-seawater interactions and explores the annual variations and spatial distributions in submarine groundwater discharge (SGD) and seawater intrusion (SWI) in the Bohai Sea coastal zone in Tianjin, China. A three-dimensional finite element model, FEMWATER in the GMS environment, is developed to simulate density-dependent flow and transport in coastal groundwater aquifers. A sensitivity analysis is used to explore how the model output varies with the hydrogeological parameters and boundary conditions. The results suggest that both SGD and SWI occur across the sea-aquifer interface. Along the modeled 45 km stretch of coastline, the annual SGD and SWI rates are 4.23 × 107 m3/yr and 0.86 × 107 m3/yr, respectively. The results also indicate that SGD is highest in the winter and lowest in the summer, and SWI exhibits the opposite trend. This change in flow direction across the sea-aquifer interface corresponds to seasonal changes in sea level. SGD mainly occurs in the southern and northern parts of the study area, and SWI primarily occurs in the central part. The results of the sensitivity analysis suggest that the SGD and SWI model outputs are most sensitive to sea level and the hydraulic conductivity in the top layer.

  17. Sediment quality of the SW coastal Laizhou Bay, Bohai Sea, China: a comprehensive assessment based on the analysis of heavy metals.

    Directory of Open Access Journals (Sweden)

    Xuelu Gao

    Full Text Available Historically, the Bohai Sea is one of the most important fishing grounds in China. Yet, surrounded by one of the biggest economic rims of China, its ecological functions have been declining rapidly in recent two decades under the heavy anthropogenic impacts. The Laizhou Bay is the smallest one of the three main bays in the Bohai Sea. Owing to the rich brine deposits, chemical industries using brine as raw materials are booming in the southern coast of the Laizhou Bay, the scale of which ranks as the largest one in China. In order to monitor and assess the environmental quality, surface sediments were collected from the coastal waters of southwestern Laizhou Bay and the rivers it connects with during summer and autumn in 2012, and analyzed for heavy metals. Several widely adopted methods were used in the overall assessment of heavy metal pollution status and potential ecological risks in these sediments, and the data were analyzed to infer the main sources of the pollutants. The results showed that the remarkably high concentrations of heavy metals were almost all recorded in a small number of riverine sites. Cr, Cu, Ni and Zn were the main environmental threat according to the sediment quality guidelines. The marine area was generally in good condition with no or low risk from the studied metals and adverse effects on biota could hardly occur. Natural sources dominated the concentrations and distributions of Cu, Ni, Pb and Zn in the marine area. Our results indicated that heavy metal pollution was not a main cause of the ecological degradation of the Laizhou Bay at present.

  18. Field Observation and Analysis of Wave-Current-Sediment Movement in Caofeidian Sea Area in the Bohai Bay, China

    Institute of Scientific and Technical Information of China (English)

    左利钦; 际永军; 汪亚平; 刘怀湘

    2014-01-01

    In order to study the mechanism of flow-sediment movement, it is essential to obtain measured data of water hydrodynamic and sediment concentration process with high spatial and temporal resolution in the bottom boundary layer (BBL). Field observations were carried out in the northwest Caofeidian sea area in the Bohai Bay. Near 2 m isobath (under the lowest tidal level), a tripod system was installed with AWAC (Acoustic Wave And Current), ADCP (Acoustic Doppler Current Profilers), OBS-3A (Optical Backscatter Point Sensor), ADV (Acoustic Doppler Velocimeters), etc. The accurate measurement of the bottom boundary layer during a single tidal period was carried out, together with a long-term sediment concentration measurement under different hydrological conditions. All the measured data were used to analyze the characteristics of wave-current-sediment movement and the BBL. Analysis was performed on flow structure, shear stress, roughness, eddy viscosity and other parameters of the BBL. Two major findings were made. Firstly, from the measured data, the three-layer distribution model of the velocity profiles and eddy viscosities in the wave-current BBL are proposed in the observed sea area; secondly, the sediment movement is related closely to wind-waves in the muddy coast area where sediment is clayey silt:1) The observed suspended sediment concentration under light wind conditions is very low, with the peak value generally smaller than 0.1 kg/m3 and the average value being 0.03 kg/m3;2) The sediment concentration increases continuously under the gales over 6-7 in Beaufort scale, under a sustained wind action. The measured peak sediment concentration at 0.4 m above the seabed is 0.15-0.32 kg/m3, and the average sediment concentration during wind-wave action is 0.08-0.18 kg/m3, which is about 3-6 times the value under light wind conditions. The critical wave height signaling remarkable changes of sediment concentration is 0.5 m. The results show that the suspended load

  19. 基性岩油气储层白CO2封存潜力及可行性初探——以下辽河坳陷青龙台辉绿岩油气藏为例%POTENTIAL CAPACITY AND FEASIBILITY OF CO2 SEQUESTRATION IN PETROLEUM RESERVOIRS OF BASALTIC ROCKS: EXAMPLE FROM THE QINGLONGTAI DIABASE HYDROCARBON RESERVOIR IN THE EASTERN SAG OF XIALIAOHE DEPRESSION,BOHAI BAY BASIN,EAST CHINA

    Institute of Scientific and Technical Information of China (English)

    王震宇; 吴昌志; 季峻峰; 陈振岩; 陈旸; 李军; 杨光达; 顾连兴

    2011-01-01

    The Liaohe oilfield, situated in Xialiaohe Depression, Bohai Bay Basin, Eastern China, is famous for their igneous-related hydrocarbon reservoirs. The Qinglongtai diabase hydrocarbon reservoir, located in the central part of the eastern sag of the depression, covers an area of 1.3km2, with a proven oil geological reserve of 750, 000 tons and an output of 31.96 t of oil and current amount of 7856m3 of gas per day. In this paper,we analyze the geological features and reservoir characteristics of Qinglongtai diabase hydrocarbon reservoir. Combined with mineral and chemical compositions of four diabase core samples, we evaluate the feasibility of CO2 sequestration in petroleum reservoirs of basaltic rocks, and then estimate the CO2 storage capacity of minerals and oil and gas reservoir of the Qinglongtai diabase hydrocarbon reservoir. Our results show that reservoir spaces and minerals which suffer carbonation easily are favorable spots for CO2 sequestration, while the cap rocks can prevent the emission of CO2,and the stability of hydrocarbon reservoir can guarantee the safety of CO2 injection ,and should be an ideal target for CO2 sequestration. Estimates of theoretical capacity for CO2 storage assume that all the pore space freed up by the production of recoverable hydrocarbon reserves will be replaced by CO2. Therefore the theoretical storage capacity of oil and gas reservoirs can be estimated using most recent reserve databases from the Liaohe oilfield. Based on the principle of water-CO2-rock reaction, the capacity of the marie minerals in diabase for CO2 sequestration can also be calculated. According to the preliminary calculation, potential mineral capacity for reaction with CO2 is 46. 0 × 106 tons, while capacity of oil and gas reservoir to storage CO2 supercritical fluid is 4.90× 106 tons, and total capacity of CO2 sequestration for the Qinglongtai hydrocarbon reservoir is 18.4×l06 tons.%辉绿岩油气藏储层一方面含有大量可与CO2反应生成

  20. Relationship between salt diapirism and faulting in the central structural belt of the Dongying sag, Bohai Gulf basin, China

    Institute of Scientific and Technical Information of China (English)

    YU Jianguo; LI Sanzhong; WANG Jinduo; TIMOTHY M Kusky; WANG Xinhong; LU Shengqiang

    2005-01-01

    Many growth faults developed in the Dongying sag of the Jiyang depression of the Bohai Gulf basin, China. These normal growth faults consist of flower-like grabens in the hanging walls of the major faults, accompanied by reverse dragging. The central structural belt is an important structural unit in the Dongying sag, and is divided into a series of small blocks by these faults. These internal blocks can be classified into five structural classes, including parallel blocks, arc-shape blocks, plume-like blocks, ring-radial blocks,and splay blocks. It is shown that these complicated block classes and the "negative flower-like" fault associations in the central structural belt resulted from regional NNW-SSE extension accompanying local salt diapirism and related reverse dragging, rather than strike-slip faulting. On the basis of the diapirism strength, diapers in the central structural belt can be divided into lower salt ridges and pillows, and blind piercing structures. Diapirs are mainly composed of some salts with a little soft mudstone and gypsum. These structures began forming during deposition of the Sha 3 member and terminated during deposition of the Guangtao formation.

  1. Species-and tissue-specific mercury bioaccumulation in five fish species from Laizhou Bay in the Bohai Sea of China

    Institute of Scientific and Technical Information of China (English)

    LIU Jinhu; CAO Liang; HUANG Wei; DOU Shuozeng

    2013-01-01

    Mercury (Hg) concentrations in the tissues (muscle,stomach,liver,gills,skin,and gonads)of five fish species (mullet Liza haematocheilus,flathead fish Platycephalus indicus,sea bass Lateolabrax japonicus,mackerel Scomberomorus niphonius and silver pomfret Pampus argenteus) collected from Laizhou Bay in the Bohai Sea of China were investigated.The results indicate that Hg bioaccumulation in the five fish was tissue-specific,with the highest levels in the muscle and liver,followed by the stomach and gonads.The lowest levels were found in the gills and skin.Fish at higher trophic levels (flathead fish and sea bass) exhibited higher Hg concentrations than consumers at lower trophic levels.Mercury bioaccumulation tended to be positively correlated with fish length in mullet,silver pomfret,mackerel,and flathead fish,but was negatively correlated with fish length in sea bass.The Hg concentrations in the muscles of all fish species in Laizhou Bay were within the permissible limits of food safety set by national and international criteria.However,the suggesting maximum consumption of sea bass is 263 g per week for human health.

  2. Operational Efficiency Evaluation of Iron Ore Logistics at the Ports of Bohai Bay in China: Based on the PCA-DEA Model

    Directory of Open Access Journals (Sweden)

    Jihong Chen

    2016-01-01

    Full Text Available Operational efficiency is significant for the comprehensive competitiveness of a port. In this study, we use a principal component analysis-data envelopment analysis (PCA-DEA integrated model to evaluate the operational efficiency of iron ore logistics at the ports of Bohai Bay, China. The key indicators and systematic framework are established for logistics efficiency research. We consider the PCA-DEA integrated model as a practical tool for evaluating and analyzing the relative efficiency of the iron ore logistics of each port in that area. The proposed method consists of a two-stage research and analysis that begins with PCA. In the first stage, we use PCA to obtain 6 synthetic indicators, including 4 input indicators and 2 output indicators, from 15 original indicators. In the second stage, the standard DEA approach is used with the specific synthetic indicators. The evaluation results of the selected ports from the integrated PCA-DEA model are compared and discussed. The comparison of the evaluation results indicates that the PCA-DEA model provides a practical and powerful tool for the investigation of the port logistics problem. With this integrated model, a comparison analysis and further research into the iron ore logistics efficiency of different ports in the area are presented. Finally, discussions and suggestions are provided.

  3. Outstanding Development of Laybarge Installation Technique by Bohai Oil Corp.

    Institute of Scientific and Technical Information of China (English)

    Wang Shufen

    1994-01-01

    @@ In order well to suit the nee p for the offshore oil development and construction in the Bohai Bay area the Bohai Oil Corporation (BOC)successfully worked out the laybarge installation technique for the subsea pipeline construction, thus,to make it applicable to the construction of subsea pipelines at various water depth for all the offshore oilfieldsn the country.

  4. Clay Mineral Distribution Patterns of Tertiary Continental Oil-bearing Basins in China

    Institute of Scientific and Technical Information of China (English)

    Zhao Xingyuan

    1996-01-01

    @@ Induction This paper studies the clay mineral distribution patterns of Tertiary continental oil-bearing basins in China. More than 9 000 shale samples from Paleogene (E) to Neogene (N) Series distributed in Bohai Gulf, Subei, Jianghan,Nanxiang, Zhoukou, Sanshui, Beibu Bay, East China Sea,Hetao, Juiquan, Qaidam and Tarim basins, and so on.

  5. Composition and Provenance of Sandstones and Siltstones in Paleogene, Huimin Depression, Bohai Bay Basin, Eastern China

    Institute of Scientific and Technical Information of China (English)

    Zhang Jinliang; Zhang Xin

    2008-01-01

    This study was conducted to distinguish the compositions and provenance of sandstones and siltstones in the Ek1-Es3 members of Huimin (惠民) depression. The samples have been analyzed for petrographic, major element and selected trace element compositions (including REE). The results show that the sandstones from the first member of Kongdian (孔店) Formation (Ek1) have higher quartz compositions than those from the fourth member (Es4) and the third member (Es3) of Shahejie (沙河街) Formation. The alkali feldspar/plagioclase ratio in the A-CN-K diagrams decreases in the order Ek1>Es4>Es3, which suggests that the Ek1 member had a more alkali feldspar-rich granitoid source and more intense weathering of the source than the Es4 and Es3 members. The mineral distributions in the A-CN-K diagrams also indicate that the sandstones and slltstones in the three members underwent K-metasomatism. Extrapolation of the sandstones and siltstones back to the plaginclase-alkali feldspar line in the A-CN-K diagram suggests a high average plagioclase to alkali feldspar ratio in the provenance (tonalite to granite). In addition, the chemical index of weathering (CIW) and chemical index of alteration (CIA) parameters of the sandstones and siltstones suggest that the weathering of the first cycle material was intense, and the CIW decreases in the order Ek1>Es4>Es3. Trace element ratios suggest all the sedimentary rocks were mostly derived from granitoids. Elemental ratio plots (e.g., Th/Sc vs. Eu/Eu*) of sandstones and siltstones suggest a mix of a granodiorite-tonalite source as a source of the sandstones and siltstones. The sandstones and siltstones of Es3 and Es4 members also contain higher Eu/Eu* and lower Th/Sc ratios than the sandstones and siltstones of Ek1 member. As is consistent with the petrography, it suggests that the sandstones and siltstones of Es3 and Es4 members are derived from a source with less granite and more granodiorite-tonalite than the sandstones and siltstones of Ek1 member.

  6. 渤海湾近岸海域石油类现状与评价%THE STATUS QUO AND ASSESSMENT OF PETROLEUM IN THE BOHAI BAY INSHORE SEA AREAS

    Institute of Scientific and Technical Information of China (English)

    阚文静; 张秋丰; 石海明

    2013-01-01

    Based on the environment surveys at inshore sea areas near Bohai Bay for 2008 to 2011,the horizontal and vertical distributions and the annual changes of petroleum hydrocarbons concentration in this sea area was analyzed.In addition,environment quality assessment was also conducted for this area by using single factor pollution index method.The results showed that the horizontal distributions of Bohai Bay,the coastal waters of petroleum hydrocarbons content north-central higher than the south,with regard to the vertical changes,the average concentrations of petroleum hydrocarbons in the surface layer were higher than those in the bottom.Combined with previous findings,obtained the inter-annual variation of the 2002 to 2011.Bohai Bay coastal waters in water content of petroleum hydrocarbons have fluctuated,but overall are relatively stable.Results can be considered according to the evaluation of the single-factor pollution index,the Bohai Bay coastal waters have already received the petroleum hydrocarbons pollution should be of concern.%根据2008-2011年渤海湾近岸海域的调查结果,分析了该海域石油类含量的水平分布、垂直分布和年度变化,并采用单因子污染指数法,进行了该海域的环境质量状况评价.结果表明,从水平分布看渤海湾近岸海域石油类含量中北部高于南部,从垂直分布看,其石油类的含量大体呈现出表层高、底层低的特征,结合前人的调查结果,得出2002-2011年渤海湾近岸海域水体中石油类含量的年际变化虽时有波动,但总体较为平稳.根据单因子污染指数的评价结果认为,渤海湾近岸海域已经受到石油类的污染,应引起关注.

  7. Nutrients, heavy metals and phthalate acid esters in solar greenhouse soils in Round-Bohai Bay-Region, China: impacts of cultivation year and biogeography.

    Science.gov (United States)

    Chen, Zhiqun; Tian, Tian; Gao, Lihong; Tian, Yongqiang

    2016-07-01

    Solar greenhouse is a common facility type used for horticultural crop production in China. However, most solar greenhouse fields have been degraded due to continuous cropping and excessive fertilizer use. Therefore, we investigated solar greenhouse soils covering a wide range of cultivation years and environmental conditions in Round-Bohai Bay-Region to test the effects of cultivation year and biogeography on nutrients, heavy metals, and phthalate acid esters (PAEs). In general, soil pH decreased while soil electrical conductivity (EC), organic matter (OM), total nitrogen (TN), NO3 (-)-N, NH4 (+)-N, mineral nitrogen (MN), Olsen-P, and NH4OAc-K contents increased as time of cultivation increased. However, this trend was influenced by sampling sites. Among sampling sites, Jiangsu showed a relatively low soil pH and high Olsen-P content, while Hebei showed a relatively high soil EC value, NO3 (-)-N, NH4 (+)-N, MN, and NH4OAc-K contents. Liaoning was characterized by relatively high soil OM and TN contents. The nutrient level indexes in evaluation of soil quality on Olsen-P and NH4OAc-K exceeded the standard seriously. The maximum values of the heavy metals Cd, Cu, and Zn were 4.87, 2.78, and 1.15 times higher than the threshold values, respectively. There was a rising trend on the heavy metal contents with the increasing cultivation years, and this trend was significantly influenced by sampling sites. Both Cu and Zn had relative high heavy metal indexes in evaluation of soil pollution. The PAEs were not detected in almost all sampling soils. Overall, the excessive fertilizer application was an important cause of nutrient accumulation and heavy metal pollution, resulting in soil degradation in solar greenhouses.

  8. Nutrients, heavy metals and phthalate acid esters in solar greenhouse soils in Round-Bohai Bay-Region, China: impacts of cultivation year and biogeography.

    Science.gov (United States)

    Chen, Zhiqun; Tian, Tian; Gao, Lihong; Tian, Yongqiang

    2016-07-01

    Solar greenhouse is a common facility type used for horticultural crop production in China. However, most solar greenhouse fields have been degraded due to continuous cropping and excessive fertilizer use. Therefore, we investigated solar greenhouse soils covering a wide range of cultivation years and environmental conditions in Round-Bohai Bay-Region to test the effects of cultivation year and biogeography on nutrients, heavy metals, and phthalate acid esters (PAEs). In general, soil pH decreased while soil electrical conductivity (EC), organic matter (OM), total nitrogen (TN), NO3 (-)-N, NH4 (+)-N, mineral nitrogen (MN), Olsen-P, and NH4OAc-K contents increased as time of cultivation increased. However, this trend was influenced by sampling sites. Among sampling sites, Jiangsu showed a relatively low soil pH and high Olsen-P content, while Hebei showed a relatively high soil EC value, NO3 (-)-N, NH4 (+)-N, MN, and NH4OAc-K contents. Liaoning was characterized by relatively high soil OM and TN contents. The nutrient level indexes in evaluation of soil quality on Olsen-P and NH4OAc-K exceeded the standard seriously. The maximum values of the heavy metals Cd, Cu, and Zn were 4.87, 2.78, and 1.15 times higher than the threshold values, respectively. There was a rising trend on the heavy metal contents with the increasing cultivation years, and this trend was significantly influenced by sampling sites. Both Cu and Zn had relative high heavy metal indexes in evaluation of soil pollution. The PAEs were not detected in almost all sampling soils. Overall, the excessive fertilizer application was an important cause of nutrient accumulation and heavy metal pollution, resulting in soil degradation in solar greenhouses. PMID:26996919

  9. An Analysis of the Interaction of Regional Economy and Environment in the Bohai Sea Basin by CGE Modeling (Special Issue in honor of Professor Ryoji Moriya’s Retirement)

    OpenAIRE

    櫻井, 一宏

    2013-01-01

    Recently, human activities cause the water contamination problems in the closed water areas and the enclosed coastal sea areas around the world.In China, the Bohai Sea is the only enclosed coastal sea area in the large land area, which is getting polluted by socio-economic activity in the catchmentarea. The basin includes the capital city and some large cities (e.g.Beijing, Tianjin, and Dalian etc.), which are rapidly xpanding and developing economically with rising populations. In this study...

  10. Genetic diversity analysis of spawner and recaptured populations of Chinese shrimp (Fenneropenaeus chinensis) during stock enhancement in the Bohai Bay based on an SSR marker

    Institute of Scientific and Technical Information of China (English)

    WANG Mosang; WANG Weiji; XIAO Guangxia; LIU Kefeng; HU Yulong; TIAN Tao; KONG Jie; JIN Xianshi

    2016-01-01

    Eight microsatellite markers were used to analyze genetic diversity, level of inbreeding, and effective population size of spawner and recaptured populations of Chinese shrimp (Fenneropenaeus chinensis) during stock enhancement in the Bohai Bay in 2013. A total of 254 and 238 alleles were identified in the spawner and recaptured populations, respectively, and the numbers of alleles (Na) were 8–63 and 6–60, respectively. The numbers of effective alleles (Ne) were 2.52–21.60 and 2.67–20.72, respectively. The polymorphism information content ranged from 0.529 to 0.952. The observed heterozygosity (Ho) values (0.638–0.910 and 0.712–0.927) were lower than the expected heterozygosity (He) values (0.603–0.954 and 0.625–0.952), which indicated that the two populations possessed a rich genetic diversity. In 16 tests (2 populations×8 loci), 13 tests deviated from the Hardy-Weinberg equilibrium.Fis values were positive at seven loci and the inbreeding coefficients (F) of the two populations estimated by trioML were 13.234% and 11.603%, suggesting that there was a relatively high degree of inbreeding. A certain level of inbreeding depression had occurred in the Chinese shrimp population.Fst values ranged from 0 to 0.059, with a mean of 0.028, displaying a low level of genetic differentiation in the two populations. Effective population sizes (3 060.2 and 3 842.8) were higher than the minimum number suggested for retaining the evolutionary potential to adapt to new environmental conditions. For enhancement activity in 2014, the ideal number of captured shrimp spawners should have ranged from 7 686 to 19 214 to maintain genetic diversity and effective population size. Further strategies to adjust the balance of economic cost, fishing effort and ideal number of shrimp spawners to maintain a satisfactory effective population size for ensuring the sustainability of Chinese shrimp are proposed.

  11. 渤海湾海底隧道运营风险评估分析%Risk assessment on Bohai Bay subsea tunnel in its operational period

    Institute of Scientific and Technical Information of China (English)

    王永红; 刘兵; 张永刚

    2013-01-01

    The operation of super-long subsea tunnel is a extremly complex system project,has larger un-certainty and safety risk. The procedure of risk assessment was explained in detail,and its application on Bohai Bay subsea tunnel project was proposed as a case study in this paper. Firstly,lots of different risk factors of the subsea tunnel operation were identified systematically,which involved water damage,tunnel lining crack,tun-nel freezing,tunnel lining corrosion,tunnel earthquake disaster,the air pollution inside the cave,tunnel fire and the train derailment accident. Then,those operational risks were analyzed and assessed by the confidence in-dex method and analytic hierarchy process,and were classified and discussed gradually according to the risk ac-ceptance criterion. Finally,some topics about risk assessment on the subsea tunnel operational risk needed to the further research were high-lighted here.%特长海底隧道运营是一个极其复杂的系统工程,存在较大的不确定性和安全风险。根据隧道工程运营期风险评估的一般流程,对渤海湾海底隧道工程在其运营期的风险进行了评估。评估中考虑的主要风险因素有水害、衬砌裂损、冻害、衬砌腐蚀、震害、洞内空气污染、火灾和列车脱轨事故8种类型。综合运用信心指数法和层次分析法,参照隧道与地下工程风险接受准则和风险等级标准,对渤海湾海底隧道运营期间的风险进行估计与评价。给出了该海底隧道运营期的风险等级,并讨论了本评估工作中尚存在的一些问题和今后有待深入的工作。

  12. Preliminary Study on Chub Mackerel Resources in Laizhou Bay of Bohai Sea in Different Historical Periods%不同历史时期渤海莱州湾鲐鱼资源初探

    Institute of Scientific and Technical Information of China (English)

    盖清霞

    2014-01-01

    The Laizhou Bay is one of the three bays in the Bohai Sea .From ancient times to today , the changes of chub mackerel resources of the Laizhou Bay have been obvious ,w hose notable feature is that chub mackerel can come and go from time to time .The reason is that chub mackerel is not suit-able to live in the muddy waters .Soil erosion in the Loess Plateau leads to the increase of silt content of the Yellow River ,and the Yellow River inflowing into the Bohai Sea affects the transparency of the Laizhou Bay .In recent decades ,the Laizhou Bay has suffered from the industrial pollution along the coast and land-based pollution in the rivers on the ground ,which worsens the marine environment of the Laizhou Bay .Nowadays ,chub mackerel has almost disappeared in the Laizhou Bay due to a varie-ty of intertwined factors .%莱州湾是渤海的三大海湾之一。从古至今,莱州湾的鲐鱼资源变动就十分明显,显著特征是时有时无。其主要原因为鲐鱼不适宜在浑浊的海水里生存。黄土高原的水土流失导致了黄河泥沙含量的提高,而黄河注入到渤海中则影响了莱州湾海水的透明度。近几十年来,莱州湾还受到了沿岸的工业污染和地上河流的陆源污染,这使得莱州湾的海洋环境更加恶化。现如今,多种因素交织导致鲐鱼基本上在莱州湾消失了。

  13. Research of paleoenvironment and its impact on coastline evolvement in Bohai Bay%渤海湾海岸古气候环境及其对海岸变迁的影响

    Institute of Scientific and Technical Information of China (English)

    白玉川; 杨艳静; 王靖雯

    2011-01-01

    以渤海湾西岸这一典型淤泥质海岸为背景,从研究古气候环境出发,利用相关考古资料和前人的成果,重建渤海湾西岸全新世以来的气候环境,得到渤海湾的气候变化情况.通过分析孢粉化石资料,初步恢复渤海湾地区4个特征位置的古气候、古环境.针对渤海海域水环境,建立距今2500~2000年前、距今1000年前和公元2004年的渤海二维潮流数学模型,通过分析流场变化构建出从古至今海岸变迁演变过程(冲淤演变).研究古气候环境变化与海岸变迁的关系,探索古气候环境影响下的海岸变迁的内因和外延,综合古气候变化、海平面变化等影响因素,总结得出渤海湾海岸古气候环境(温度、降水、潮流风浪等)对海岸变迁的影响,并对未来海岸线的变化趋势进行预测.%Based on the fact that the west coast of Bohai Bay is a typical muddy coast, paleoclimate and paleoenvironment are both studied. This paper makes an analysis of the pollen fossil according to the relevant archaeological data and related research results of Bohai Bay region and makes a preliminary reconstruction of paleoclimate of the region since Holocene, then the climate changes are obtained. This paper makes an analysis of the pollen fossil of Bohai Bay region and makes a preliminary recovery of four typical locations' paleoclimate and paleoenvironment of the region. This paper establishes a tide mathematical model of the Bohai Bay region under three different periods; AD 2004, 1128 B. P. And 2500 B. P.. At first, the mathematical model is proved reliable by the comparison of the measured data and the model test data of the 2004 model. Thus, numerical models of the other two conditions can be built. And then, this paper makes a comparison and analysis of the characteristics of the rising tide, ebb rush of three models. Finally, this paper studies the relationship between the paleoclimate changes and coastline evolution, explores

  14. Geochemical Characteristic of Mesozoic Granite of the Penglai 9-1 Buried Hill,Bohai Bay and Its Geological Significance%渤海海域蓬莱9-1构造潜山中生代花岗岩元素地球化学特征及其地质意义

    Institute of Scientific and Technical Information of China (English)

    冯冲; 王清斌; 杨波; 赵国祥; 刘晓健

    2016-01-01

    渤海海域蓬莱9-1大型油田是国内首次发现的中生代花岗岩潜山油藏,该岩体的地球化学特征和成因研究为渤海湾盆地中生界构造环境和陆壳生长机制提供了重要的线索。应用 LA-ICP-MS 获得蓬莱9-1潜山花岗岩体锆石 U-Pb 年龄为164±2Ma,代表岩体的形成时代。ω(SiO2)范围62.22%~70.86%,ω(K2 O)范围3.29%~4.36%,ω(CaO)范围1.71%~4.10%,碱度率 AR 为2.13~3.06,含铝指数 A/CNK 介于0.89~1.07之间,表明该岩体为准铝-弱过铝范围的高钾钙碱性Ⅰ型花岗岩;REE 配分模式程较陡的右倾模式,富集轻稀土元素(LREE)、强烈亏损重稀土元素(HREE),大离子亲石元素(LILE)富集、高场强元素 HFSE 贫化,总体具有消减带地球化学特征,表明岩浆源区与消减带组分存在密切相关;δEu 略微正异常,高 Sr、Sr/Y、La/Yb 和低 Y、Yb、Mg#特征具有增厚基性下地壳部分熔融形成埃达克岩的特征;R1-R2判别图解和(Y+Nb)-Rb 构造图解指示其形成于碰撞后的拉张阶段。综上分析,蓬莱9-1潜山花岗岩体为碰撞造山过程地壳增厚背景下,后碰撞阶段由于地幔上隆致使具消减带组分的下地壳物质发生部分熔融所致。其形成标志着渤海湾盆地中生代陆块汇聚碰撞的强烈主碰撞阶段已经结束,并在164Ma 期间进入到由主碰撞挤压转向后碰撞伸展演化阶段,为进一步精细确定渤海湾盆地中生代陆块汇聚碰撞造山过程提供了新的依据。%The large Penglai 9-1 oilfield in the Bohai Bay Basin is the first discovered buried hydrocarbon reservoir of the Mesozoic granite.The geochemical characteristics and origin of the rocks provide important clues for the mechanism of Mesozoic tectonic environment of and continental crust growth of Bohai Bay Basin.A new age of 164 ±2 Ma was obtained for the Penglai 9-1 granitic

  15. 渤海湾西部表层沉积物粒度及黏土矿物特征分析%The sediment grain size characteristics and analysis of sources in the western Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    冯秀丽; 魏飞; 刘杰; 刘潇; 徐芳

    2015-01-01

    对渤海湾西部海域和西岸入海河流中76个表层沉积物样品进行粒度及黏土矿物分析,研究表明该区有3种沉积物类型,黏土质粉砂分布于整个研究区,约占表层样的90%,是研究区最主要的沉积物类型;研究区黏土矿物以伊利石为主,黏土矿物组合为伊利石-高岭石-绿泥石-蒙皂石;渤海湾西部表层沉积物主要来源于海河等渤海湾西岸入海河流中的陆源碎屑物,滦河对研究区基本没有影响,黄河对研究区的影响变得比较小。对于研究渤海湾西岸的沉积特征及沉积物物源、了解陆地河流对于研究区海洋沉积环境的影响有着一定的科学意义。%This paper shows that there are 3 types of sediments in the study area according to analysis of 76 surface samples which were sampled from the western Bohai Bay waters and rivers that flow into the sea from the west coast. Clayey silt distributes throughout the study area, and is the most important type of sediments in the study area, accounting for about 90% of the surface samples. The sediment dynamic environmental characteristics of the sur-face sediments in the area were studied using the Flemming triangle graphic method and the results indicate that the sedimentary dynamics in the study area was relatively weak. The clay mineral analysis of 60 surface samples shows that the illite is the main clay mineral, and the clay mineral assemblage in the study area is illite - kaolinite - chlorite - smectite stone. The exploration of sediment source based on grain size and clay minerals shows that the surface sediments of the western Bohai Bay were mainly from the terrigenous detritus, which were carried by the rivers flowing into the sea in the western Bohai coast, such as the Haihe River, while the Luanhe River had nearly no effect on the surface sediments in the study. The influence of the Yellow River on the sea surface sediments was weak.

  16. Hydrocarbon Migration and Accumulation in Dongying Basin

    Institute of Scientific and Technical Information of China (English)

    Li Chunguang; Shang Weirong

    1996-01-01

    @@ Dongying basin is a faulted basin rich in hydrocarbon and is under more exploration (wildcat well density is 0.155 well/km ) in the southern Bohai Bay area of China, covering an area of 5700 km. Based on the paleotopographic setting of Paleozoic basement rocks, the basin was evolved into Mesozoic and Cenozoic basin which was faulted in the north and overlapped in the south by the blockfaulting movement in J2-J3. So, each formation of the source rocks in Paleogene is characterized by thick deposit in the north and thin deposit in the south.

  17. The fate of nutrients and phosphates in Akrotiri Bay, Cyprus Basin (Eastern Mediterranean Levantine Basin)

    International Nuclear Information System (INIS)

    The pathways and the levels of the concentrations of nutrients resulting from the discharge of treated effluents from the Limassol Sewage Treatment Plant (SALA) and from marine fish farms in Akrotiri Bay were studied through numerical simulations of the dispersion of phosphates and nitrates. The use of a dispersion model made it possible to evaluate different courses of action regarding both, the protection of the marine ecosystem and the development of marine fish farm activities. Akrotiri Bay is a semi-open coastal sea area in the Eastern Mediterranean Levantine Basin bounded to the North and West from the south coastline of Cyprus. Nutrients inputs from the discharges of SALA result in the elevation of the background levels of nutrients and in particular those of phosphates

  18. 烃源岩测井识别在渤海湾石油开发中的应用%Well Logging Evaluation of Source Rock and Its Application in Bohai Bay Oil Exploitation

    Institute of Scientific and Technical Information of China (English)

    汤丽娜

    2011-01-01

    statistical analysis between well logging information and the core carbon content. Comparing with different methods for organic carbon content calculations, the Passey formula method is found to fit well with the core geochemistry method, and with a small relative error. The Passey formula method is basically confirmed that it satisfies the demand for hydrocarbon source rock evaluation in Bohai Bay oilfield. The processing results of 20 wells indicate that there is higher organic carbon content and thicker source rock in Shahejie lacustrine Formation. Especially, the middle of the third zone of Shahejie Formation is the most beneficial layer of source rock.

  19. 基于Bayes方法的渤海渔业资源动态评析%A Stock Assessment of Bohai Sea by Bayes-based Pella-Tomlinson Model

    Institute of Scientific and Technical Information of China (English)

    李九奇; 聂小杰; 叶昌臣; 尹增强

    2012-01-01

    研究利用来自于黄渤海渔政局的内部统计资料,采用基于Bayes方法的Pella-Tomlinson模型对渤海渔业资源动态进行了科学评析,评析结果显示:渤海渔业资源的环境容纳量为3.5×106~5.5×106t;渔业资源综合种群的内禀增长率r为0.9~1.6;1979年渔业资源年平均生物量为2 332 523 t,尔后持续上升到1985年的最高值4 251 292 t,1985年以后又持续下降到2002年的最低值2 250 709 t;渤海渔业资源的最大持续产量MSY约为140×104t左右;支持MSY所需的捕捞努力量约为817 771 kW,到1991年捕捞努力量增加到963 564 kW,此时已超过获得MSY时需要的捕捞努力量,即从1991年开始出现捕捞过度。%The fish stock assessment is important groundwork for present-day fish stock management,The report presents a stock assessment of Bohai Sea by Bayes-based Pella-Tomlinson model.All of the data used in this study are from the Bohai-Yellow Sea Fisheries Administration Bureau.The research results show that the carrying capacity K of Bohai Sea is about 3.5×106-5.5×106 t and the Intrinsic growth rate r is about 0.9-1.6;the estimated stock biomass increased from approximately 2332523 t in 1979 to the maximum value 4251292 t in 1985 and then declined to less than 2250709 t in 2002;the estimated MSY is 1400000 t;the estimated effort for achieving MSY is 817771 kW and the effort is 963564 kW in 1991,since then overfishing was started.

  20. 渤海湾大型底栖动物群落组成及与环境因子的关系%Community Component of Macrobenthos in Bohai Bay and Their Relationships with Environmental Factors

    Institute of Scientific and Technical Information of China (English)

    谷德贤; 刘茂利; 王娜

    2011-01-01

    The marine investigation, cluster analysis, multidimensional scaling (MDS)-, and the canonical correspondence analysis(CCA)were selected to study the community component of macrobenthos in the Bohai Bay and their relationships with environmental factors. A total of 31 macrobenthos species were collected, 8 species were polychaete, 12 species were mollusc, 4 species were crustacea, 3 species were echinoderm, 1 species was chordata, 1 species was nemertean, 1 species was echiuridae, 1 species was hemichordates. The dominant species was Potamocorbula amurensis. The average density and biomass of the macrobenthos in the Bohai Bay were 91.2 ind/m2 and 83.06 g/m2 .The cluster analysis and multidimensional scaling showed that their distribution had obvious spatial heterogeneity, 4 station groups were simply divided. CCA showed that pH, DO, depth, transparence had strong relationship with macrobenthos.%采用海上定点采样调查、等级聚类(CLUSTER)、多维排序标度(MDS)、典范对应分析(CCA)等多种方法,研究了2009年春季渤海湾大型底栖动物种类组成及其与环境因子的相关性。本次调查共采集到大型底栖动物31种,其中多毛类8种,软体动物12种,.甲壳动物4种,棘皮动物3种,脊索动物、纽形动物、蜢虫门、半索动物各1种,大型底栖动物优势种为黑龙江河蓝蛤。调查海域大型底栖动物的平均密度为91.2个/m2,平均生物量为83.06g/m2。CLUSTER和MDS分析表明,大型底栖动物的分布具有显著的空间差异性,依此将大型底栖动物简单地分为4个群落。CCA分析显示,pH、溶解氧、透明度、水深与大型底栖动物分布的相关性较大。

  1. Comparison of summer thermohaline field and circulation structure of the Bohai Sea between 1958 and 2000

    Institute of Scientific and Technical Information of China (English)

    WU Dexing; WAN Xiuquan; BAO Xianwen; MU Lin; LAN Jian

    2004-01-01

    The analysis of observed salinity data over 35 years (1961-1996) at four stations around the Bohai Sea, i.e. Huludao, Qinhuangdao, Tanggu and Beihuangcheng, reveals that the salinity of the 4 observation stations has increased 1.1, 1.6, 1.9 and 0.4, respectively. The data also show that over the past 35 years, there have been at least 5 large salinity variation processes. The salinity data from two cruises of the Bohai Sea in August 1958 and 2000, show that the salinity pattern of the Bohai Sea has changed markedly. Low salinity in the sea surface layer around the old Yellow River mouth in August 1958 had been replaced by high salinity in August 2000 and the maximum variation of salinity is over 10.0. In addition, the values and distribution of salinity were almost the same from surface to bottom there in August 2000, but there existed significantly different salinity levels between the surface layer and the deep layer in August 1958. When a comparison is made between the salinity levels of the above-mentioned two years, it is found that the salinity in August 2000 is on average 2.0 higher than that of August 1958 in the main part of the Bohai Sea. The change of temperature and salinity field in the Bohai Sea leads to the change of the circulation. The numerical simulation shows that in comparison with the circulation structure of the Bohai Sea in August 1958, the circulation in August 2000 changes markedly. The significant changes of circulation appeared in Bohai Bay, Laizhou Bay and in the middle of the Bohai Sea. The clockwise current loop outside of the Bohai Bay and counterclockwise current loop outside of the Laizhou Bay in August 1958 disappeared in August 2000, and the counterclockwise current loop of the Bohai Bay migrated obviously outward. The flow direction in the Laizhou Bay turned 180° around. Corresponding to the variation of the Bohai Sea circulation, the amount of water exchange between the Bohai Sea and the Yellow Sea has also changed. The water

  2. Origin and Distribution of Hydrogen Sulfide in Oil-Bearing Basins, China

    Institute of Scientific and Technical Information of China (English)

    ZHU Guangyou; ZHANG Shuichang; LIANG Yingbo

    2009-01-01

    The concentration of hydrogen sulfide gas (H_2S) varies greatly in the oil-bearing basins of China, from zero to 90%. At present, oil and gas reservoirs with high H_2S concentration have been discovered in three basins, viz. the Bohai Bay Basin, Sichuan Basin and the Tarim Basin, whereas natural gas with low H_2S concentration has been found in the Ordos Basin, the Songiiao Basin and the Junggar Basin. Studies suggest that in China H_2S origin types are very complex. In the carbonate reservoir of the Sichuan Basin, the Ordos Basin and the Tarim Basin, as well as the carbonate-dominated reservoir in the Luojia area of the Jiyang depression in the Bohai Bay Basin, Wumaying areas of the Huanghua depression, and Zhaolanzhuang areas of the Jizhong depression, the H_2S is of Thermochemical Sulfate Reduction (TSR) origin. The H_2S is of Bacterial Sulphate Reduction (BSR) origin deduced from the waterflooding operation in the Changheng Oiifieid (placanticline oil fields) in the Songliao Basin. H_2S originates from thermal decomposition of sulfur-bearing crude oil in the heavy oil area in the Junggar Basin and in the Liaohe heavy oil steam pilot area in the western depression of the Bohai Bay Basin. The origin types are most complex, including TSR and thermal decomposition of sulfcompounds among other combinations of causes. Various methods have been tried to identify the origin mechanism and to predict the distribution of H_2S. The origin identification methods for H_2S mainly comprise sulfur and carbon isotopes, reservoir petrology, particular biomarkers, and petroleum geology integrated technologies; using a combination of these applications can allow the accurate identification of the origins of H_2S. The prediction technologies for primary and secondary origin of H_2S have been set up separately.

  3. Bohai Suryongs: Who Were They?

    Directory of Open Access Journals (Sweden)

    Alexander Kim

    2015-03-01

    Full Text Available Author considers question on Bohai suryongs, the places of them in Bohai are unclear. Many scholars in East Asia consider suryongs as chiefs of tribes, who lived in Bohai peripheries. However, other historians believe that suryongs were provincial officials. Usually the problem of these Bohai chiefs is discussed between these two opinions. Author thinks that the structure of suryongs consists of different groups of provincial leaders. Because many Bohai chiefs had different functions and positions in the state, clearly, in many cases the kinds of their activity were inconsistence. Therefore author of article has another opinion about suryongs in Bohai state. Moreover, in many cases Bohai chiefs can be position or rank. Suryongs played a big role in govern administrative system, we can information about activity of Bohai suryongs not only in inner policy, but in foreign relations too. It had influence in potential of Bohai in different periods of state existing. Moreover, suryongs system existed after collapse of Bohai state during a long time. The system of Bohai suryongs was well-known in other countries. Author uses materials not only in European (Russian and English, but in Asian languages (Korean and Chinese too.

  4. Geochemical characteristics of the fluid inclusions in the Gangxi Fault Belt, Huanghua Depression, Bohai Bay Basin, China

    Institute of Scientific and Technical Information of China (English)

    DING Wei-wei; DAI Jin-xing; CHU Feng-you; HAN Xi-qiu

    2007-01-01

    We studied the geochemical characteristics of the fluid inclusions in the Ordovician carbonates and the Oligocene Shahejie Formation sandstones from 15 wells in the Gangxi Fault Belt, Huanghua Depression. The fluid inclusions are all secondary with gas/liquid ratio of 5%~10%. Base on Raman they are mainly composed of H2O, CO2 and CH4. The homogenization temperatures, combined with burial and geothermal history of the host rock, indicate that the fluid flows in the Shahejie Formation and the Ordovician carbonates were trapped in Neocene. Using a VG5400 mass spectrometer, the helium isotopic compositions were analyzed. Interpretation of results suggested a significant amount of mantle-derived helium mainly accumulating in the intersections of the NWW trending Xuzhuangzi and NE trending Gangxi faults. The maturity of hydrocarbon decreases from the intersection to the outside pointing out that the fluid related to the NWW trending Xuzhuangzi and NE trending Gangxi faults.These factors implied the fluid inclusions have a close relationship to the local tectonic setting. Gangxi Fault Belt experienced intensive Neo-tectonic activities in Cenozoic. Widespread faulted-depressions and strong volcanic eruptions manifested its tectonic status of extensional stress field. Mantle uplift caused the movement of magma that carried mantle-derived gases and deep heat flows, the deep-rooted tension faults provided the passages for the gases and heat flows to shallow crust levels.

  5. Helium isotopic compositions in fluid inclusions of the Gangxi fault belt in the Huanghua Depression, Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    DING Weiwei; DAI Jinxing; YANG Chiyin; TAO Shizhen; HOU Lu

    2005-01-01

    The authors obtained 30 core samples from 15 wells in Gangxi fault belt, Huanghua Depression. Using a VG5400 mass spectrometer, the helium isotopic compositions in fluid inclusion of these samples were analysed. Interpretation of results suggests a significant amount of mantle-derived helium in the inclusions, which were likely trapped during Neocene. Mantle-derived helium have mostly accumulated in the intersections of the NWW trending Xuzhuangzi and NE trending Gangxi faults, and decreased away from the intersections. This pattern implied a close relationship to the local tectonic setting. Gangxi fault belt experienced intensive neo-tectonic activities in the Cenozoic. Widespread faulted-depressions and strong volcanic eruptions manifested its tectonic status of extensional stress field. Mantle uplift caused the movement of magma that carried mantle-derived gas, and the deep-rooted tension faults provided the passages for the gases to shallow crust levels. High-content abiogenic CO2 pools occurred in the study area, hence, using the helium isotopic compositions is of great significance to the exploration of abiogenic natural gases.

  6. Changes in the shelf macrobenthic community over large temporal and spatial scales in the Bohai Sea, China

    Science.gov (United States)

    Zhou, H.; Zhang, Z. N.; Liu, X. S.; Tu, L. H.; Yu, Z. S.

    2007-09-01

    Over the past 20 years, the Bohai Sea has been subjected to a considerable human impact through over-fishing and pollution. Together with the influence of the Yellow River cut-off, the ecosystem experienced a dramatic change. In order to integrate available information to detect any change in macrobenthic community structure and diversity over space and time, data collected during the 1980s and the 1990s from 3 regions of the Bohai Sea (Laizhou Bay, 16 stations, 37-38°N, 119-120.5°E; central Bohai Sea, 25 stations, 38-39°N, 119-121°E; eastern Bohai Bay, 12 stations, 38-39°N, 118.5-119°E) were reanalyzed in a comparative way by means of a variety of statistical techniques. A considerable change in community structure between the 1980s and the 1990s and over the geographical regions at both the species and family level were revealed. After 10 years, there was a considerable increase in abundance of small polychaetes, bivalves and crustaceans but decreased number of echinoderms. Once abundant in Laizhou Bay in the 1980s, a large echinoderm Echinocardium cordatum and a small mussel Musculista senhousia almost disappeared from the surveying area in the 1990s. Coupled with the increased abundance was the increased species richness in general whereas evenness was getting lower in central Bohai Sea and Bohai Bay but increased in Laizhou Bay. K-dominance plot showed the same trend as evenness J'. After 10 years, the macrobenthic diversity in the Bohai Sea as a whole was slightly reduced and a diversity ranking of central Bohai Sea > Laizhou Bay > eastern Bohai Bay over space was also suggested. Sediment granulometry and organic content were the two major agents behind the observed changes.

  7. Phytoplankton Assemblages and Their Relation to Environmental Factors by Multivariate Statistic Analysis in Bohai Bay%渤海湾浮游植物与环境因子关系的多元分析

    Institute of Scientific and Technical Information of China (English)

    周然; 彭士涛; 覃雪波; 石洪华; 丁德文

    2013-01-01

    2007年春季和夏季对渤海湾的浮游植物和环境因子进行调查,运用多元分析技术分析浮游植物在渤海湾的分布特征及其与环境因子之间的关系.调查期间共发现浮游植物26种,其中春季17种,夏季23种.春季浮游植物平均数量为115×104 cells·m-3,显著高于夏季(3.1×104 cells·m-3).应用主成分分析(PCA)浮游植物分布特征,结果表明,春季浮游植物主要分布于渤海的中北部,是硝酸盐含量较高的水域;夏季浮游植物分布于各个水域,但优势种主要分布于河口附近.运用冗余分析(RDA)探讨浮游植物分布与环境因子之间的关系,结果表明,影响渤海湾浮游植物分布的关键环境因子,春季是硝酸盐、亚硝酸盐和溶解性活性磷酸盐,夏季是氨氮和水温.%A detailed field survey of hydrological, chemical and biological resources was conducted in the Bohai Bay in spring and summer 2007. The distributions of phytoplankton and their relations to environmental factors were investigated with multivariate analysis techniques. Totally 17 and 23 taxa were identified in spring and summer, respectively. The abundance of phytoplankton in spring was 115 ×104 cells·m-3 , which was significantly higher than that in summer (3. 1 × 104 cells·m-3 ). Characteristics of phytoplankton assemblages in the two seasons were identified using principal component analysis ( PCA ) , while redundancy analysis ( RDA ) was used to examine the environmental variables that may explain the patterns of variation of the phytoplankton community. Based on PCA results, in the spring, the phytoplankton was mainly distributed in the center and northern water zone, where the nitrate nitrogen concentration was higher. However, in summer, phytoplankton was found distributed in all zones of Bohai Bay, while the dominant species was mainly distributed in the estuary. RDA indicated that the key environmental factors that influenced phytoplankton assemblages in the

  8. 渤海湾海水ACTIFLO(R)工艺预处理中试试验%Pilot Scale Test of ACTIFLO(R) Processes for Pretreatment of Seawater in Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    杨淑霞

    2012-01-01

    天津是一个水质性缺水的沿海城市,处于渤海湾地区,海水自净能力差,污染状况较严重.为了解天津渤海湾海水水质情况,在天津塘沽海边进行了海水预处理中试试验,研究了ACTIFLO(R)高效斜板沉淀池对海水的预处理效果以及药剂投加量情况.结果表明ACTIFLO(R) SS的去除率为97.1%~99.2%;在原海水浊度变化较大情况下,可以将浊度控制在10 NTU以下;同时对藻类的平均去除率也达到91.6%.%Tianjin is a coastal city adjacent to Bohai Bay which faces fresh water scarcity, where seawater has poor self—purification ability and is suffered from severe pollution. A seawater pretreatment pilot was conducted in Tianjin seaside in order to know raw seawater quality, the pretreatment performance of ACTIFLO? As well as chemical dosing parameters. The pilot result shows SS removal rate is 97.1 %~99.2 %, outlet turbidity can remain stably less than 5 NTU for raw water with turbidity in range of 50~500 NTU, and average algae removal rate is 91.6 %.

  9. 渤海湾沿岸晚第四纪地层划分及地质意义%Stratigraphic Division of the Late Quaternary Strata along the Coast of Bohai Bay and Its Geology Significance

    Institute of Scientific and Technical Information of China (English)

    胥勤勉; 袁桂邦; 张金起; 秦雅飞

    2011-01-01

    This paper, taking four drilling holes cutting through the upper Pleistocene as an example to classify the late quaternary strata along the coast of Bohai Bay, discussed lithofacies paleogeography and neotectonic characteristics, based on lithology and sedimentary structures, 14C ages of peat and humus mud, micropaleontology and palynology, and the theory of climatic stratigraphy and sequence stratigraphy. Nine units divided are MIS5e (Marine Isotope Stage 5e), MIS5d, MIS5c, MIS5b, MIS5a, MIS4, MIS3, MIS2 and MIS1 in an ascending order. Transgressions occurred in MIS5e, MIS5c, MIS3 and MIS1. Marsh, interfluve and lagoon formed during the MIS5e due to river action equivalent to sea action. Interfluve and river and sand bank-lagoon formed during MIS5c because of river action better than sea action. 7~8 m thick of marine sediment formed when sea level rose at the early stage of MIS3, and then river and sand bank and lagoon formed when sea level fell at the late stage of MIS3 because of river action strengthening. 10 -15 m thick of marine sediment thickness formed in the northern and western coasts; 3 m thick of lagoon sediment formed in the southern coast. The ancient Yellow River deltas had prograded from south to north in the coast of Bohai bay. The hard clay and interfluves formed when sea level fell during MIS5d, MIS5b and MIS2. Marsh formed during the last deglaciation because of sea level rising. The coast of Bohai Bay was characterized by differential subsidence during the Late Quaternary. The differential subsidence rate between southern Huanghua depression and Chengning uplift reached 0. 16 mm/a, while the rate of the northern and middle sections of the Huanghua depression reached 0. 31 mm/a. MIS5c was the period of the tectonic activity.%本文以4个钻透上更新统钻孔为例,以岩性和沉积构造为基础,采用“C、微体和孢粉等分析方法,结合气候地层和层序地层学的理论,对渤海湾晚第四纪地层进行了划分,讨

  10. Probabilistic ecological risk assessment of cadmium in the Bohai Sea using native saltwater species

    Institute of Scientific and Technical Information of China (English)

    MU Jingli; WANG Juying; WANG Ying; CONG Yi; ZHANG Zhifeng

    2014-01-01

    Predicted no-effect concentration (PNEC) is often used in ecological risk assessment to determine low-risk concentrations for chemicals. In the present study, the chronic data from native saltwater species were used to calculated PNEC values using four methods: log-normal distribution (ETX 2.0), log-triangle distribution (US EPA’s water quality criteria procedure), burr III distribution (BurrliOZ) and traditional assessment fac-tor (AF). The PNECs that were calculated using four methods ranged from 0.08 μg/L to 1.8 μg/L. Three of the SSD-derived PNECs range from 0.94 to 1.8 μg/L, about a factor of two apart. To demonstrate the use of SSD-based PNEC values and comprehensively estimate the regional ecological risk for cadmium in surface water of the Bohai Sea, in the Liaodong Bay, Bohai Bay, and Laizhou Bay, China, the dissolved cadmium con-centrations were measured and obtained 753 valid data covering 190 stations from July 2006 to November 2007. Based on three ecological risk assessment approaches, namely hazard quotient (HQ), probabilistic risk quotient and joint probability curve (JPC), the potential ecological risk of cadmium in surface water of the Liaodong Bay, Bohai Bay, and Laizahou Bay were estimated. Overall, the ecological risk of cadmium to aquatic ecosystem in the whole Bohai Sea was at acceptable ecological risk level, the order of ecological risk was Liaodong Bay>Bohai Bay>Laizhou Bay. However, more concerns should be paid to aquatic ecological risk in the Liaodong Bay which is the home of many steel, metallurgy and petrochemical industrial in China.

  11. Seasonal Cycle Analysis of the Nitrate Nitrogen and Nitrite Nitrogen in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    Shi Qiang; Chen Jianglin; Li Chongde

    2002-01-01

    During 1985~1987, the concentration of nitrate nitrogen was higher in the Laizhou Bay and the Bohai Bay while that of nitrite nitrogen was higher in the Liaodong Bay and the Bohai Bay. The concentration of nitrate nitrogen was highest in winter and lowest in summer while that of nitrite nitrogen was highest in autumn and lowest in spring. The seasonal variation of the concentration of nitrate nitrogen was maximum in the Laizhou Bay and the Bohai Bay while that of the concentration of nitrite nitrogen was maximum in the Liaodong Bay. There was a great difference in the concentration of nitrate nitrogen between the surface and the bottom in autumn and in the concentration of nitrite nitrogen between the surface and the bottom in summer. The main reason for the seasonal variations of the concentration of nitrate nitrogen and nitrite nitrogen was the marine biochemical process. The nitrate nitrogen and nitrite nitrogen in the Bohai Sea basically maintained a quasi-equilibrium state seasonal cycle. The quasi-equilibrium state seasonal cycle of nitrate nitrogen and nitrite nitrogen at the bottom was stable while that at the surface was liable to variations caused by other factors.

  12. Pollution Condition of Petroleum Hydrocarbon Pollutant and Estimation of Its Environmental Capacities in Summer in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The pollution condition of petroleum hydrocarbon (PH) was summarized in the Bohai Sea in this paper. The results showed that the mean concentration of PH was (25.7±13.6)mg/m3, varying from 4.4 to 64.8 mg/m3 in the survey sea area. Laizhou Bay and Bohai Bay have been contaminated badly inshore. The dynamic model for distribution of marine PH among multiphase environments in the Bohai Sea has been established. The environmental capacities (ECo) and surplus environmental capacities (SECo) of PH have been estimated in the Bohai Sea according to the dynamic model. The results showed that the ECo separately were about 29 169 t/a, 177 306 t/a and 298 446 t/a under the first, second and third, fourth class seawater quality standards requirement. And the ECo of Bohai Bay, Liaodong Bay, Laizhou Bay and Central Bohai Sea were about 5 255 t/a, 8 869 t/a, 4889 /a and 10 156 t/a respectively under the first and second class seawater quality standards requirement.

  13. Comparing effects of land reclamation techniques on water pollution and fishery loss for a large-scale offshore airport island in Jinzhou Bay, Bohai Sea, China.

    Science.gov (United States)

    Yan, Hua-Kun; Wang, Nuo; Yu, Tiao-Lan; Fu, Qiang; Liang, Chen

    2013-06-15

    Plans are being made to construct Dalian Offshore Airport in Jinzhou Bay with a reclamation area of 21 km(2). The large-scale reclamation can be expected to have negative effects on the marine environment, and these effects vary depending on the reclamation techniques used. Water quality mathematical models were developed and biology resource investigations were conducted to compare effects of an underwater explosion sediment removal and rock dumping technique and a silt dredging and rock dumping technique on water pollution and fishery loss. The findings show that creation of the artificial island with the underwater explosion sediment removal technique would greatly impact the marine environment. However, the impact for the silt dredging technique would be less. The conclusions from this study provide an important foundation for the planning of Dalian Offshore Airport and can be used as a reference for similar coastal reclamation and marine environment protection. PMID:23608638

  14. The Structure and Origin of a Rainstorm-inducing Mesoscale Convective System on Western Coast of Bohai Bay%渤海西岸暴雨中尺度对流系统的结构及成因

    Institute of Scientific and Technical Information of China (English)

    易笑园; 李泽椿; 孙晓磊; 刘一玮; 孙密娜; 朱磊磊

    2011-01-01

    利用卫星、雷达和加密自动站等监测资料,结合VDRAS系统资料和1°×1° NCEP再分析资料,对造成黑昼和暴雨的中尺度对流系统的空间、热动力结构特征和发生、发展及维持原因进行了分析.结果表明:2004-2009年渤海西岸圆形α-中尺度对流系统有别于南方,其中只有16%可发展为中尺度复合体;黑昼现象是影响系统的特殊性所致.突发性暴雨的制造者是α-中尺度对流系统西端不断新生的β-中尺度对流系统,其发生、发展、维持与边界层内冷池外流、对流层低层(1.3~2.4 km)侵入的西北气流与西南气流形成的辐合线或交汇线有密切关系.α-中尺度对流系统的上升速度中心在500 hPa附近,多个β-中尺度对流系统分别具有独自的垂直气流和弱边界层环流.α-中尺度对流系统内部扰动温度呈下负上正的垂直分布,促使了不稳定层结趋于稳定;冷池呈东厚西薄的楔形结构,有利于β-中尺度对流系统发展维持.%Black day phenomenon and sudden hard rain occur in Tianjin on 16 June 2009. Based on several monitoring data such as FY-2 satellites data, multi-radar composite and intensive automatic stations data, combing with VDRAS data, the origins of black day and the rainstorm are analyzed. The thermal and dynamical structure which leads to the occurrence and development of meso-β-scale.meso-γ-scale convective systems in circular meso-a-scale convective system are also studied. 31 circle-shape MCSs which lead to severe weather on western coast of Bohai Bay in 2004-2009 are preliminarily sorted and summed up in size and life-circle. Less than 16%circular MαCS on the western coast of Bohai Bay develop into MCC with no more than 15 × lO4 km2 large (where the TBB is equal to or below -52℃ ) . The MCCs generally last no more than 8hours and always happen in night. But in the South China, it,s common to see MCC larger than 20 ×104 km2 which last more than 10 hours. "6

  15. Molecular detection of Candidatus Scalindua pacifica and environmental responses of sediment anammox bacterial community in the Bohai Sea, China.

    Directory of Open Access Journals (Sweden)

    Hongyue Dang

    Full Text Available The Bohai Sea is a large semi-enclosed shallow water basin, which receives extensive river discharges of various terrestrial and anthropogenic materials such as sediments, nutrients and contaminants. How these terrigenous inputs may influence the diversity, community structure, biogeographical distribution, abundance and ecophysiology of the sediment anaerobic ammonium oxidation (anammox bacteria was unknown. To answer this question, an investigation employing both 16S rRNA and hzo gene biomarkers was carried out. Ca. Scalindua bacteria were predominant in the surface sediments of the Bohai Sea, while non-Scalindua anammox bacteria were also detected in the Yellow River estuary and inner part of Liaodong Bay that received strong riverine and anthropogenic impacts. A novel 16S rRNA gene sequence clade was identified, putatively representing an anammox bacterial new candidate species tentatively named "Ca. Scalindua pacifica". Several groups of environmental factors, usually with distinct physicochemical or biogeochemical natures, including general marine and estuarine physicochemical properties, availability of anammox substrates (inorganic N compounds, alternative reductants and oxidants, environmental variations caused by river discharges and associated contaminants such as heavy metals, were identified to likely play important roles in influencing the ecology and biogeochemical functioning of the sediment anammox bacteria. In addition to inorganic N compounds that might play a key role in shaping the anammox microbiota, organic carbon, organic nitrogen, sulfate, sulfide and metals all showed the potentials to participate in the anammox process, releasing the strict dependence of the anammox bacteria upon the direct availability of inorganic N nutrients that might be limiting in certain areas of the Bohai Sea. The importance of inorganic N nutrients and certain other environmental factors to the sediment anammox microbiota suggests that these

  16. Size-fractionated phytoplankton standing stock and primary production in the Bohai Sea during late spring

    Institute of Scientific and Technical Information of China (English)

    宁修仁; 蔡昱明; 刘子琳; 柴扉

    2002-01-01

    --During June 1997 cruise by R/V Science No. 1, observations on temporal and spatial variations of the size-fractionated phytoplankton standing stock and primary production were carried out in the Bohai Sea. The size-fractionated chlorophyll a (Chl a) and primary production, photosynthetically available radiation (PAR), as well as the related physico-oceanographic and zooplanktonic parameters were measured at five time-series observation stations representing sub-areas of the sea. Results obtained show that there were the marked features of spatial zonation of Chl a and primary production in the Bohai Sea. The values in the Laizhou Bay, the Liaodong G ulf and the Bohai Gulf were high and showed close relation with tidal fluctuations, i.e. high Chl a concentration occurred during high tide in the Laizhou Bay, and during low tide in the Liaodong Gulf and the Bohai Gulf. In the strait and the central region of the Bohai Sea, the values were relatively low and no relationship with tidal fluctuation could be found. Chlorophyll a concentration vertically decreased from surface to bottom in the Liaodong Gulf and the Bohai Gulf, while it increased in the Laizhou Bay, the strait and the central region of the Bohai Sea, and the highest value was encountered at the bottom. Size-fractionation results showed that nano - combining pico -plankton ( < 20 μm) predominated in phytoplankton communities of the Bohai Sea during late spring. The average contribution to total Chi a in each station ranged 76% ~ 95% (mean is 87% ). The contribution of net ( > 20μm), nano - (2~ 20μm) and picoplankton ( < 2 μm) was 13%, 63% and 24% to total production, and 9%, 53% and 38% to total Chl a, respectively. It proved the importance of nano - and pico -plankton in phytoplankton communities in the Bohai Sea ecosystems. In this paper the factors, such as light intensity and zooplankton grazing pressure, governing standing stock and production of phytoplankton in the Bohai Sea were also

  17. Simulation of potential nitrate leaching in croplands of typical watershed around Bohai Bay using DNDC model%基于DNDC 模型的环渤海典型小流域农田氮素淋失潜力估算

    Institute of Scientific and Technical Information of China (English)

    李虎; 邱建军; 高春雨; 王立刚

    2012-01-01

    为了定量评价流域尺度氮素污染的可能性并探明氮素污染的主要来源,以期指导农业生产实际保护农田生态环境,该文主要运用农业生态系统生物地球化学模型(DNDC)模拟的方法,以环渤海典型小流域——小清河流域为例,在GIS流域数据库支持下对该流域氮素淋失潜力进行了估算.研究结果表明,2006年小清河流域年均氮淋失负荷范围为10.44×103~36.86×103t,平均为23.65×103t.以当年氮肥投入总量222.2×103t计算,该流域平均氮素流失量占氮肥投入的10.6%.不同地区氮素淋失空间分布差别较大,与氮肥施用最的空间分布规律大体一致.其中,44%和27%的地区氮素潜在淋失量分别集中在20~40和>40~80 kg/hm2,这些地区主要分布在小清河两侧沿岸及寿光市大部分地区,给流域水环境造成了较大影响.研究结果显示流域氮淋失存在较大的空间区域差异,根据不同地区的实际情况进行水氮管理,减少氮素的无效丢失十分必要.%Nitrogen (N) leaching from agricultural systems plays a key role in the water contamination. Quantifying potential nitrogen leaching at watershed scale is important for providing mitigation policies or strategies. Taking the typical small watershed-Xiaoqinghe basin around Bohai Bay as an example, this paper selected the denitrification-decomposition model (DNDC), combined with detailed soil hydrological and biogeochemical processes, to predict nitrogen leaching of croplands in the watershed under the support of GIS database. The results showed that simulations of the DNDC model was reasonable and had good agreement with observations of annual amounts of leached water and rates of nitrate leaching from 3 typical cropping systems in Xiaoqing River basin. According to the tested DNDC model, the potential N leaching loads ranged from 10.44×103to 36.86×103t, with an average of 23.65×103 t in the watershed in 2006. Taking the amount of total

  18. 采用ICC-qPCR法分析渤海湾表层海水中的轮状病毒%ICC-qPCR Analysis on the infectious rotavirus in the surface seawater of Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    明红霞; 董玉波; 任莹利; 王林同; 朱琳

    2012-01-01

    Rotavirus (RV) is the major cause of severe gastroenteritis, especially for infants and children. Due to its long duration and low dose-response in the water environment, it is urgent to establish a rapid and effective method to quantify this pathogen. Molecular biological assays have overcome time-consuming, as well as insensitive disadvantages of traditional cell culture method. However, viral inlectivity can not be analyzed by this method. Therefore, integration of the cell culture techniques and the reverse transcription quantitative PCR (ICC-RT-qPCR) was introduced in 2010 and 2011 to identify the contamination by rotaviruses in winter seawater samples of Bohai Bay, Tianjin, China. 500-mL seawater was concentrated, cultivated for 48h, and then quantified by qPCR. ICC-qPCR revealed that 3 of 7 samples were positive for infectious rotavirus. The concentration of rotavirus was from 1.8×102 copies to 3.8×103 copies, and estimated at 1 to 39 PFU/L The result confirmed that ICC-qPCR in combination with the real-time PCR method not only reduced the detection duration, improved sensitivity, but also able to quantitate the rotavirus. Hence, it will become a practical tool for widespread studies on aquatic environmental monitoring for viral contamination.%轮状病毒是引起婴幼儿急性腹泻的重要病原体之一,在水环境中存活时间长,导致人类感染的剂量低,因此寻求一种快速高效的定量检测海水中的轮状病毒方法势在必行.传统的细胞培养技术不但耗时,而且灵敏度低,现代分子生物学技术虽然克服了上述缺点,但是其感染性的信息无从获得.因此,本文建立了细胞培养结合实时定量PCR (ICC-qPCR)的方法,并于2010年冬季对渤海湾天津近岸重点海域表层海水中具有感染性的轮状病毒进行了定量调查.500 mL海水经浓缩,4.8h细胞培养之后,用qPCR方法在7个海水样品中检测出3个样品具有感染性,其测定值范围为1.8×102 copies-3.8

  19. Land use change in Bohai Rim: a spatialtemporal analysis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Based on RS and GIS methods, land use information for 1985 and1995 was acquired from TM images and analyzed. Then on both spatial and temporal aspects, this paper analyzes land use change in three provinces of Hebei, Shandong and Liaoning and two municipalities of Beijing and Tianjin in the Bohai Rim covering the period of 1985 to 1995. The extent, rate, areal difference and trend of various types of land use changes in the region, as well as spatial changes of major types of land use, their distribution characteristics and regional orientation are revealed. The regional characteristics of land use are elaborated, so as to provide effective policy support for sustainable land use in the area around the Bohai Bay.

  20. Distribution of nutrients and eutrophication assessment in the Bohai Sea of China

    Institute of Scientific and Technical Information of China (English)

    WANG Xiulin; CUI Zhengguo; GUO Quan; HAN Xiurong; WANG Jiangtao

    2009-01-01

    Water samples were collected in 120 stations in the Bohai Sea of China to analyze the distribution of dissolved nutrients and assess the degree of eutrophication in August 2002. The result shows that the average concentration of DIN increased and the PO4-P concentration sharply decreased compared to the previous data of corresponding period. The high concentrations of DIN and PO4-P occurred in coastal waters, especially in the bays and some river estuaries, while the high concentrations of SiO3-Si in the surface and middle depth occurred in the central area of the Bohai Sea. The average ratio of DIN/ PO4-P was much higher than the Redfield Ratio (16:1). Apparently, PO4-P was one of the limiting nutrient for phytoplankton growing in the sea. The average concentrations of DON and DOP were higher than their inorganic forms. The results of eutrophication assessment show that 22.1% of all stations were classified as violating the concentration levels of the National Seawater Quality Standard (GB 3097-1997) for DIN and only 3.9% for PO4-P. The average eutrophication index in the overall area was 0.21±0.22 and the high values occurred in Bohai Bay, Liaodong Bay and near the Yellow River estuary. This means that the state of eutrophication was generally mesotrophic in the Bohai Sea, but relatively worse in the bays, especially some river estuaries.

  1. The fate of nutrients and phosphates in Akrotiri Bay, Cyprus Basin (Eastern Mediterranean Levantine Basin)

    International Nuclear Information System (INIS)

    The pathways and the levels of the concentrations of nutrients resulting from the discharge of treated effluents from the Limassol Sewage Treatment Plant (SALA) and from marine fish farms in Akrotiri Bay were studied through numerical simulations of the dispersion of phosphates and nitrates. The use of a dispersion model made it possible to evaluate different courses of action regarding both, the protection of the marine ecosystem and the development of marine fish farm activities

  2. Spare parts management in Bohai bay

    OpenAIRE

    Zhigao, Shangguan

    2013-01-01

    Spare parts management plays a critical part in the Oil and gas (O&G) industry. Traditional asset management could not meet the requirement of present equipment. Due to the complexity of inventory plus limitation of offshore platform, it is one complicated issue to accomplish effective and efficient inventory control for offshore operation. Having reasonable inventory is crucial for improving the continuous efficiency for spare parts and decreasing the maintenance budget, especially for the o...

  3. Shining Pearl of the Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    WUXINYI

    2003-01-01

    AFTER successful experi-mentation in south China's SEZs, the reform and opening policy was applied to coastal cities, and then to central and western China. Shenzhen and Shanghai's Pudong constitute the economic backbone of the Zhujiang and Yangtze River

  4. Compensation Claims on Marine Ecological Damages of Oil Spill of Bohai Bay%渤海溢油事故海洋生态损害赔偿研究——以墨西哥湾溢油自然资源损害赔偿为鉴

    Institute of Scientific and Technical Information of China (English)

    刘丹

    2012-01-01

    2011年我国渤海溢油事故引起社会强烈关注,尤其对我国海洋环境保护相关法律形成挑战。本文着眼于2010年墨西哥湾溢油事故中的相关赔偿问题,比较美国溢油自然资源损害赔偿制度,分析了渤海溢油事故中涉及的"海洋生态损害"的概念界定、责任主体与索赔主体、赔偿范围、索赔额度及评估标准等法律问题,总结并分析渤海溢油事故对完善我国海洋生态损害赔偿制度的启示。%The 2011 oil spill in Bohai Bay caused widespread attention in China,the recent marine environmental laws was therefore challenged by the Chinese society.The first part introduces the oil spill accident and the recent progress of the claims on marine e- cological damages,the legal system of marine ecological damages will also be coved in this part.The second part analyzes the natu- ral resources damage claim of 2010 oil spill in the Gulf of Mexico and the law of natural resources in the US.The third part pro- vides detailed analysis about the legal problems of Bohai oil spill,i.e.,definition of "marine ecological damage" , the responsible parties and the qualified parties to claim for the damages,the regime of compensation,the compensation limits and the evaluation crite- ria.The last part of this article will summarize the inspirations of Bohai oil spill accident on the legal system of China's miarine ecological damage.

  5. Environmental capacity of chemical oxygen demand in the Bohai Sea: modeling and calculation

    Institute of Scientific and Technical Information of China (English)

    ZHAO Xixi; WANG Xiulin; SHI Xiaoyong; LI Keqiang; DING Dongsheng

    2011-01-01

    A three-dimensional advection-diffusion model coupled with the degradation process is established for describing the transport of chemical oxygen demand (COD). Comparison of the simulated distribution of COD at the surface in the Bohai Sea in August, 2001 with field observations, shows that the model simulates the dataset reasonably well. The Laizhou Bay, Bohai Bay, and Liaodong Bay were contaminated heavily near shore. Based on the optimal discharge flux method, the Environmental Capacity (EC) and allocated capacities of COD in the Bohai Sea are calculated. For seawater of Grades I to IV of the Chinese National Standard, the ECs of COD in the Bohai Sea were 77×104t/a, 116×l04t/a, 154×l04t/a and 193×104t/a, respectively. The Huanghe (Yellow) River pollutant discharge accounted for the largest percentage of COD at 14.3%, followed by that of from the Liugu River (11.5%), and other nine local rivers below 10%. The COD level in 2005 was worse than that of Grade II seawater and was beyond the environmental capacity. In average, 35% COD reduction is called to meet the standard of Grade I seawater.

  6. Sea Level and Paleoenvironment Control on Late Ordovician Source Rocks, Hudson Bay Basin, Canada

    Science.gov (United States)

    Zhang, S.; Hefter, J.

    2009-05-01

    Hudson Bay Basin is one of the largest Paleozoic sedimentary basins in North America, with Southampton Island on its north margin. The lower part of the basin succession comprises approximately 180 to 300 m of Upper Ordovician strata including Bad Cache Rapids and Churchill River groups and Red Head Rapids Formation. These units mainly comprise carbonate rocks consisting of alternating fossiliferous limestone, evaporitic and reefal dolostone, and minor shale. Shale units containing extremely high TOC, and interpreted to have potential as petroleum source rocks, were found at three levels in the lower Red Head Rapids Formation on Southampton Island, and were also recognized in exploration wells from the Hudson Bay offshore area. A study of conodonts from 390 conodont-bearing samples from continuous cores and well cuttings from six exploration wells in the Hudson Bay Lowlands and offshore area (Comeault Province No. 1, Kaskattama Province No. 1, Pen Island No. 1, Walrus A-71, Polar Bear C-11 and Narwhal South O-58), and about 250 conodont-bearing samples collected from outcrops on Southampton Island allows recognition of three conodont zones in the Upper Ordovician sequence, namely (in ascendant sequence) Belodina confluens, Amorphognathus ordovicicus, and Rhipidognathus symmetricus zones. The three conodont zones suggest a cycle of sea level changes of rising, reaching the highest level, and then falling during the Late Ordovician. Three intervals of petroleum potential source rock are within the Rhipidognathus symmetricus Zone in Red Head Rapids Formation, and formed in a restricted anoxic and hypersaline condition during a period of sea level falling. This is supported by the following data: 1) The conodont Rhipidognathus symmetricus represents the shallowest Late Ordovician conodont biofacies and very shallow subtidal to intertidal and hypersaline condition. This species has the greatest richness within the three oil shale intervals to compare other parts of Red

  7. Macrobenthic community response to copper in Shelter Island Yacht Basin, San Diego Bay, California.

    Science.gov (United States)

    Neira, Carlos; Mendoza, Guillermo; Levin, Lisa A; Zirino, Alberto; Delgadillo-Hinojosa, Francisco; Porrachia, Magali; Deheyn, Dimitri D

    2011-04-01

    We examined Cu contamination effects on macrobenthic communities and Cu concentration in invertebrates within Shelter Island Yacht Basin, San Diego Bay, California. Results indicate that at some sites, Cu in sediment has exceeded a threshold for "self defense" mechanisms and highlight the potential negative impacts on benthic faunal communities where Cu accumulates and persists in sediments. At sites with elevated Cu levels in sediment, macrobenthic communities were not only less diverse but also their total biomass and body size (individual biomass) were reduced compared to sites with lower Cu. Cu concentration in tissue varied between species and within the same species, reflecting differing abilities to "regulate" their body load. The spatial complexity of Cu effects in a small marina such as SIYB emphasizes that sediment-quality criteria based solely on laboratory experiments should be used with caution, as they do not necessarily reflect the condition at the community and ecosystem levels. PMID:21354577

  8. Bohai Prominent for Cooperation with Foreign Firms

    Institute of Scientific and Technical Information of China (English)

    Han Qingbing; Wang Zhan; Du Genqi

    1997-01-01

    @@ Bohai Oilfields started to cooperate with foreign firms earlier than other oil fields. From 1980 up to now, Bohai Oilfields has signed 14 petroleum cooperation contracts with 18 foreign oil firms from Japan, France, the United States and Britain. The total investment for cooperative exploration and development is nearly $1.5 billion. In addition, Bohai Oilfields,taking various forms for cooperation, has formed a number of specialized joint ventures for offshore operation in partnership with foreign technical companies.

  9. Status and understanding of groundwater quality in the North San Francisco Bay groundwater basins, 2004

    Science.gov (United States)

    Kulongoski, Justin T.; Belitz, Kenneth; Landon, Matthew K.; Farrar, Christopher

    2010-01-01

    Groundwater quality in the approximately 1,000-square-mile (2,590-square-kilometer) North San Francisco Bay study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in northern California in Marin, Napa, and Sonoma Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA North San Francisco Bay study was designed to provide a spatially unbiased assessment of untreated groundwater quality in the primary aquifer systems. The assessment is based on water-quality and ancillary data collected by the USGS from 89 wells in 2004 and water-quality data from the California Department of Public Health (CDPH) database. The primary aquifer systems (hereinafter referred to as primary aquifers) were defined by the depth interval of the wells listed in the CDPH database for the North San Francisco Bay study unit. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifers; shallower groundwater may be more vulnerable to surficial contamination. The first component of this study, the status of the current quality of the groundwater resource, was assessed by using data from samples analyzed for volatile organic compounds (VOC), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. This status assessment is intended to characterize the quality of groundwater resources within the primary aquifers of the North San Francisco Bay study unit, not the treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used for evaluating groundwater quality for those constituents that have Federal and (or

  10. 渤海湾北岸Bg10孔磁性地层研究及其构造意义%Magnetostratigraphy and Tectonic Significance of Bg10 Borehole in Northern Coast of Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    袁桂邦; 胥勤勉; 王艳; 杨吉龙; 秦雅飞; 杜东

    2014-01-01

    Based on detailedsedimentological and magnetostratigraphic study of Bg10 borehole (600m)in the northern coast of Bohai bay,there are 39 sedimentary units and 8 normal magnetozones and 7 reverse magnetozones according on 516 specimens (456 specimens subjected to progressive thermal demagnetization and 60 specimens subjected to alternating field demagnetization ) calculated the characteristic remanent magnetization (ChRM)directions.Thinking about sedimentation rates of different magnetozones,Comparing to the geomagnetic polarity timescale (Cande et al.,1995;Gradstein et al., 2004),the normal magnetozones N1,N2,N3,N4,N5,N6 and N7 can be correlated with C1n,C1r.1n, C2n,C2r.1n,C2An.1n,C2An.2n and C2An.3n,the reverse magnetozones R1,R2,R3,R4,R5 and R6 can be collated with C1r.1r,C1r.2r+C1r.3r,C2r.1r,C2r.2r,C2An.1r and C2An.2r.The B-M and M-G boundary of borehole are located in 162.3m and 475.8m respectively,and the age of the bottom is less than 3.596Ma.There have been three sedimentation phases.The Ⅰphase which age was 3.3~3.5Ma and sedimentation rate was more than 130m/Ma was tectonic active period and could be correlated with the phase A of Qingzang movement.The Ⅱ phase which age was 1 .9~3 .3 Ma and sedimentation rate was 112m/Ma was tectonic silent period,and the sedimentary process could be controlled by climate change, but there had the different subsidence rate between Huanghua depression and Cangxian uplift.There was a tectonic active period aged 1 .0~1 .2 Ma in the Ⅲ phase which age was 0~1 .9 Ma and sedimentation rate was 202m/Ma,which could be correlated with Kunhuang movement.The sedimentary process should be controlled by tectonics and climate and the subsidence rates of Huanghua depression and Cangxian uplift have been different since 1.0Ma.Tangshan-Xingtai fault could be formed at 1.9Ma,and has developed one sag at the intersection with Zhangjiakou-Penglai fault.%对渤海湾北岸孔深600m的Bg10孔进行了详细的沉积学

  11. Temporal and spatial characteristics of harmful algal blooms in the Bohai Sea during 1952-2014

    Science.gov (United States)

    Song, Nan-qi; Wang, Nuo; Lu, Yue; Zhang, Jian-ru

    2016-07-01

    Evidence was collected from harmful algal bloom (HAB) outbreaks in the Bohai Sea during 1952-2014. The geographic information system (GIS) was used to analyse the temporal and spatial distributions of these HAB events and, subsequently, to map the distribution of these events. The results reveal the following: (1) four areas had a high frequency of HABs: Bohai Bay, the coastal waters of the cities of Qinhuangdao and Yingkou, and the Yellow River estuary. In these areas, HABs occurred a total of 142 times, 18 of which exceeded 1000 km2 in area. After 2000, the frequency of HAB outbreaks increased significantly. (2) The HAB occurrences exhibited significant seasonality (occurring during June to August). (3) Outbreaks of the dominant HAB plankton species, Noctiluca scientillans, Prorocentrum dentatum, Phaeocystis globosa, and Skeletonema costatum, occurred 57, 11, 9, and 8 times, respectively. (4) Bohai Bay, the coastal waters of Qinhuangdao, and the Yellow River estuary suffered great harm caused by these HABs. This study utilized a visual approach to more fully identify the scope, distribution, and characteristics of HABs in the Bohai Sea over the past 63 years, thus providing useful information to support the monitoring and management program for HABs.

  12. A New Small Drifter for Shallow Water Basins: Application to the Study of Surface Currents in the Muggia Bay (Italy

    Directory of Open Access Journals (Sweden)

    Carmelo Nasello

    2016-01-01

    Full Text Available A new small drifter prototype for measuring current immediately below the free surface in a water basin is proposed in this paper. The drifter dimensions make it useful for shallow water applications. The drifter transmits its GPS location via GSM phone network. The drifter was used to study the trajectory of the surface current in the Muggia bay, the latter containing the industrial harbor of the city of Trieste (Italy. The analysis has been carried out under a wide variety of wind conditions. As regards the behavior of the drifter, the analysis has shown that it is well suited to detect the water current since its motion is marginally affected by the wind. The study has allowed detecting the main features of the surface circulation within the Muggia bay under different meteorological conditions. Also, the study has shown that the trajectory of the surface current within the bay is weakly affected by the Coriolis force.

  13. Spatial distribution and loading amounts of particle sorbed and dissolved perfluorinated compounds in the basin of Tokyo Bay.

    Science.gov (United States)

    Zushi, Yasuyuki; Ye, Feng; Motegi, Mamoru; Nojiri, Kiyoshi; Hosono, Shigeo; Suzuki, Toshinari; Kosugi, Yuki; Yaguchi, Kumiko; Masunaga, Shigeki

    2012-09-01

    In this study, we analyzed over 30 types of PFCs, including precursors in both the dissolved phase and particle solid phase, in 50 samples of river water collected from throughout the Tokyo Bay basin. PFCs were detected in suspended solids (SSs) at levels ranging from traffic area (R(2) in a double logarithmic plot: 0.29-0.55). Those spatial trends were similar to the trends in dissolved PFCs. We estimated the loading amount of PFCs into Tokyo Bay from six main rivers and found that more than 90% of the total PFCs reached Tokyo Bay in the dissolved phase. However, 40.0-83.5% of the long chain PFCAs (C12-C15), were transported as particle sorbed PFCs. Rain runoff events might increase the loading amount of PFCs in SS. Overall, the results presented herein indicate that greater attention should be given to PFCs, especially for longer chain PFCs in SS in addition to dissolved PFCs. PMID:22698375

  14. Assessment of Ecosystem Service Value in the Bohai Sea%渤海海域生态系统功能服务价值评估

    Institute of Scientific and Technical Information of China (English)

    索安宁; 于永海; 苗丽娟

    2011-01-01

    In this paper, the Bohai Sea was divided into five parts, i.e. Liaodong Bay, Bohai Bay, Laizhou Bay, center of Bohai and Bohai strait. And ten types of ecosystem service function were established, including fish production, gene resource provision, 02 production, climate regulation, pollutant purification, biological control, leisure and entertainment, research and education, primary production and biodiversity conservation based on the four major functions, of material production, environmental, regulation, culture and entertainment, and service supporting. Assessment of ecosystem service values in the Bohai Sea was complished as follows. Value of ecosystem service in the Bohai Sea is 55.885 billion RMB, among which, the supporting service accounts for 32.84%, the regulation service account for 29.69%, and the cultural service for 27.74%. In the spatial pattern, Liaodong Bay, Bohai Bay and center of Bohai are the main body of the ecosystem service in the Bohai Sea, accounting for 26.25%, 20.85% and 38.47% respectively of the total ecosystem service value in the Bohai Sea Biodiversity conservation service value is the biggest in the center of Bohai, next in the Bay Liaodong Bay, Bohai Bay, while leisure and entertainment is the biggest in the Liaodong Bay, and next in the Bohai Bay.%将渤海海域划分为辽东湾、渤海湾、莱州湾、渤海海峡和渤海中部五个部分,以海洋生态服务功能的物质生产、环境调节、文化娱乐、服务支持四大功能为基础,构建了水产品生产、提供基因资源、氧气生产和气候调节、污染物净化、生物控制、休闲娱乐、科研文化、初级生产、物种多样性维持等十项服务功能价值的评估方法。对渤海海域生态服务功能价值进行了定量评价。结果表明:渤海海域生态系统服务功能价值为558.85亿元,其中支持服务功能价值占32.84%,环境调节功能价值占29.69%,文化娱乐功能价值占27.74

  15. Trace and major elements in geological samples from Itingusssu River Basin, Sepetiba Bay - Rio de Janeiro

    International Nuclear Information System (INIS)

    The Itingussu drainage basin is situated at 22 deg 44' - 22 deg 55' SL and 44 deg 53' - 43 deg 55' WL, in Coroa-Grande district, Sepetiba Bay, southwest of Rio de Janeiro, Brazil. Its total area is less than 10 km2 and includes a waterfall with three drop offs. The study area is located in a granitic pre-Cambrian embasement, discharging in a mangrove forest fringe. This work attempts to investigate the influence of lithology types in the elemental composition of soil of region and sediments of related mangrove. Instrumental neutron activation analysis and subsequent gamma-ray spectrometry were used. This technique enabled the measurement of at least twenty-one chemical elements. The more representative soil samples were enriched with U and Th. Multivariate Statistical Analysis showed that the soil and sediments formed in this area have been influenced by the leucocratic rocks, enriched with LREE and Th. The factorial analysis enables the identification of five factors of influence in the ordination of elements: presence of iron minerals (biotite); presence of allanite; marine influence in the sediment; differentiated kinetic of transport and diagenesis. (author)

  16. Delineating incised stream sediment sources within a San Francisco Bay tributary basin

    Science.gov (United States)

    Bigelow, Paul; Benda, Lee; Pearce, Sarah

    2016-07-01

    Erosion and sedimentation pose ubiquitous problems for land and watershed managers, requiring delineation of sediment sources and sinks across landscapes. However, the technical complexity of many spatially explicit erosion models precludes their use by practitioners. To address this critical gap, we demonstrate a contemporary use of applied geomorphometry through a straightforward GIS analysis of sediment sources in the San Francisco Bay Area in California, USA, designed to support erosion reduction strategies. Using 2 m lidar digital elevation models, we delineated the entire river network in the Arroyo Mocho watershed (573 km2) at the scale of ˜ 30 m segments and identified incised landforms using a combination of hillslope gradient and planform curvature. Chronic erosion to the channel network was estimated based on these topographic attributes and the size of vegetation, and calibrated to sediment gage data, providing a spatially explicit estimate of sediment yield from incised channels across the basin. Rates of erosion were summarized downstream through the channel network, revealing patterns of sediment supply at the reach scale. Erosion and sediment supply were also aggregated to subbasins, allowing comparative analyses at the scale of tributaries. The erosion patterns delineated using this approach provide land use planners with a robust framework to design erosion reduction strategies. More broadly, the study demonstrates a modern analysis of important geomorphic processes affected by land use that is easily applied by agencies to solve common problems in watersheds, improving the integration between science and environmental management.

  17. Total maximum allocated load calculation of nitrogen pollutants by linking a 3D biogeochemical-hydrodynamic model with a programming model in Bohai Sea

    Science.gov (United States)

    Dai, Aiquan; Li, Keqiang; Ding, Dongsheng; Li, Yan; Liang, Shengkang; Li, Yanbin; Su, Ying; Wang, Xiulin

    2015-12-01

    The equal percent removal (EPR) method, in which pollutant reduction ratio was set as the same in all administrative regions, failed to satisfy the requirement for water quality improvement in the Bohai Sea. Such requirement was imposed by the developed Coastal Pollution Total Load Control Management. The total maximum allocated load (TMAL) of nitrogen pollutants in the sea-sink source regions (SSRs) around the Bohai Rim, which is the maximum pollutant load of every outlet under the limitation of water quality criteria, was estimated by optimization-simulation method (OSM) combined with loop approximation calculation. In OSM, water quality is simulated using a water quality model and pollutant load is calculated with a programming model. The effect of changes in pollutant loads on TMAL was discussed. Results showed that the TMAL of nitrogen pollutants in 34 SSRs was 1.49×105 ton/year. The highest TMAL was observed in summer, whereas the lowest in winter. TMAL was also higher in the Bohai Strait and central Bohai Sea and lower in the inner area of the Liaodong Bay, Bohai Bay and Laizhou Bay. In loop approximation calculation, the TMAL obtained was considered satisfactory for water quality criteria as fluctuation of concentration response matrix with pollutant loads was eliminated. Results of numerical experiment further showed that water quality improved faster and were more evident under TMAL input than that when using the EPR method

  18. 基于RS的渤海湾沿岸近20年生态系统服务价值变化分析%Analysis on the value change of ecosystem services in coastal areas of the Bohai Bay in recent 20 years based on the remote sensing

    Institute of Scientific and Technical Information of China (English)

    苗海南; 刘百桥

    2014-01-01

    In this paper, the sea use activities in coastal areas of the Bohai Bay in recent 20 years were analyzed based on the precisely corrected remote sensing images in 1992 and 2012, and the value change of ecosystem services in the areas was evaluated, according to the recently published ecosystem value equivalent. It was shown that, because of highly intense utilization in recent 20 years, the loss of marine ecosystem services in coastal areas of the Bohai Bay was great, which was about 4 379 million RMB per year. The greatest losses of marine ecosystem service value per unit area were caused by the construction land, bare land, salt pan, and waste disposal land occupying the original water areas and marshy grounds, which were about 4 063 million, 1 245 million, 123 million and 17 million RMB per year, respectively. The loss of marine ecosystem service value in Tianjin was about 1 815 million RMB per year, accounting for 41.38%of the total loss.%以几何精校正后的1992年和2012年遥感(RS)影像为数据源,对渤海湾沿岸近20年海域开发活动进行了分类统计,并参照现有生态系统服务价值当量研究成果,对该海域生态系统服务价值变化进行了估算和分析。结果表明,近20年来对渤海湾沿岸的高强度开发导致海岸带生态系统服务价值损失较大,约为43.79亿元/年,其中,建设用地、裸露地、盐田和废物处置用地占用原来开阔环境水域和滩涂导致单位面积生态系统服务价值损失最大,损失的价值总量分别为40.63亿元/年、12.45亿元/年、1.23亿元/年和0.17亿元/年;天津市沿岸海域的生态系统服务价值损失了18.12亿元/年,占研究区域生态系统服务价值总损失量的41.38%。

  19. 基于生态事件的企业社会回应研究——以蓬莱19-3油田溢油案为例%Research on Corporate Social Responsiveness Based on Ecological Events: A Case Study of Penglai 19-3 Field Incident in Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    胡建军; 金炜东; 董大勇

    2013-01-01

    企业在生态事件中有效回应社会压力对企业、社会和生态环境的可持续发展具有重要意义.基于企业社会回应的理论与方法,对蓬莱19-3油田溢油事件中康菲公司的企业社会回应进行了深入分析,研究发现企业的社会责任担当、生态环保的立法执法环境、政府处置生态环境事故的效率、社会公众的生态环保意识是企业社会回应有效性的关键影响因素,并从企业内部管理和外部环境建设两方面对提高生态事件中企业社会回应有效性提出建议.%It has important significance for the sustainable development of enterprises, social and ecological environment that Enterprises effectively respond to social pressure in the ecological incident. Based on the theories and methods of corporate social responsiveness, this paper take in-depth analysis of Conoco Phillips China's corporate social responsiveness in Penglai 19-3 field incident in Bohai Bay. The result of our exploration indicates that, corporate social responsibility, legislation and law enforcement environment, the efficiency of government, public awareness of ecological and environmental protection are four decisive factors of corporate social responsiveness in ecological incident. From tow aspects of internal management and external environment construction, this article puts forward suggestions about related policies.

  20. Status and understanding of groundwater quality in the Monterey Bay and Salinas Valley Basins, 2005-California GAMA Priority Basin Project

    Science.gov (United States)

    Kulongoski, Justin T.; Belitz, Kenneth

    2011-01-01

    Groundwater quality in the approximately 1,000 square mile (2,590 km2) Monterey Bay and Salinas Valley Basins (MS) study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in central California in Monterey, Santa Cruz, and San Luis Obispo Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA MS study was designed to provide a spatially unbiased assessment of the quality of untreated (raw) groundwater in the primary aquifer systems (hereinafter referred to as primary aquifers). The assessment is based on water-quality and ancillary data collected in 2005 by the USGS from 97 wells and on water-quality data from the California Department of Public Health (CDPH) database. The primary aquifers were defined by the depth intervals of the wells listed in the CDPH database for the MS study unit. The quality of groundwater in the primary aquifers may be different from that in the shallower or deeper water-bearing zones; shallow groundwater may be more vulnerable to surficial contamination. The first component of this study, the status of the current quality of the groundwater resource, was assessed by using data from samples analyzed for volatile organic compounds (VOC), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. This status assessment is intended to characterize the quality of groundwater resources in the primary aquifers of the MS study unit, not the treated drinking water delivered to consumers by water purveyors. Relative-concentrations (sample concentration divided by the health- or aesthetic-based benchmark concentration) were used for evaluating groundwater quality for those constituents that have Federal and (or) California regulatory or

  1. An updated interpretation of the Hanö Bay Basin, Baltic Sea, based on recently re-processed vintage 2D seismic data

    Science.gov (United States)

    Bell, Nicholas; Sopher, Daniel; Juhlin, Christopher

    2014-05-01

    The Hanö Bay Basin is a relatively small, tectonically controlled, Mesozoic basin in the SW Baltic Sea, Northern Europe. In this study a new seismic interpretation has been made of the basin based on re-processed vintage 2D marine seismic data. A large dataset acquired between 1970 and 1984 by Oljeprospektering AB (OPAB) containing seismic lines across the Hanö Bay Basin has recently been made available by the Swedish Geological Survey (SGU). Seismic interpretation studies within the Hanö Bay Basin were last conducted in the mid-1990's. Since this time, computer power and seismic processing methods have advanced. Re-processing of a grid of lines across the Hanö Bay Basin has allowed updated interpretations to be made which more accurately reflect the geological history of the area. Multi channel seismic data from four surveys within the OPAB dataset: NA79, D72, W70 and EA73, along with two wells H1 and H4, were used in this study. An updated interpretation of the pre-Cambrian basement, which exhibits a distinctive, sharply undulating morphology, was undertaken. The basement horizon across parts of the Hanö Bay appears to be very rugose, containing a number of distinctive troughs and peaks that are over 50m in amplitude. Within these basement troughs a set of distinct packages of sediment is observed. These packages are discontinuous and are most prevalent in a small circular area in the central section of the study area. The age of these sediment packages is uncertain, being either early Mesozoic or the erosional remnants of older Paleozoic sediments. Interpretations of the re-processed seismic data indicate, in some areas, that basin fill has occurred in a significantly different way to previous interpretations during the Mesozoic. The model proposed in this study takes into account normal movement on the Christiansø Fault prior to Cretaceous inversion.

  2. High-resolution seismic analysis of the coastal Mecklenburg Bay (North German Basin): the pre-Alpine evolution

    Science.gov (United States)

    Zöllner, H.; Reicherter, K.; Schikowsky, P.

    2008-09-01

    The pre-Alpine structural and geological evolution in the northern part of the North German Basin have been revealed on the basis of a very dense reflection seismic profile grid. The study area is situated in the coastal Mecklenburg Bay (Germany), part of the southwestern Baltic Sea. From the central part of the North German Basin to the northern basin margin in the Grimmen High area a series of high-resolution maps show the evolution from the base Zechstein to the Lower Jurassic. We present a map of basement faults affecting the pre-Zechstein. The pre-Alpine structural evolution of the region has been determined from digital mapping of post-Permian key horizons traced on the processed seismic time sections. The geological evolution of the North German Basin can be separated into four distinct periods in the Rerik study area. During Late Permian and Early Triassic evaporites and clastics were deposited. Salt movement was initiated after the deposition of the Middle Triassic Muschelkalk. Salt pillows, which were previously unmapped in the study area, are responsible for the creation of smaller subsidence centers and angular unconformities in the Late Triassic Keuper, especially in the vicinity of the fault-bounded Grimmen High. In this area, partly Lower Jurassic sediments overlie the Keuper unconformably. The change from extension to compression in the regional stress field remobilized the salt, leading to a major unconformity marked at the base of the Late Cretaceous.

  3. GIS-based source identification and apportionment of diffuse water pollution: perfluorinated compound pollution in the Tokyo Bay basin.

    Science.gov (United States)

    Zushi, Yasuyuki; Masunaga, Shigeki

    2011-11-01

    To efficiently reduce perfluorinated compound (PFC) pollution, it is important to have an understanding of PFC sources and their contribution to the pollution. In this study, source identification of diffuse water pollution by PFCs was conducted using a GIS-based approach. Major components of the source identification were collection of the monitoring data and preparation of the corresponding geographic information that was extracted from a constructed GIS database. The spatially distributed pollution factors were then explored by multiple linear regression analysis, after which they were visually expressed using GIS. Among the 35 PFC homologues measured in a survey of the Tokyo Bay basin, 18 homologues were analyzed. Pollution by perfluorooctane sulfonate (PFOS) was explained well by the percentage of arterial traffic area in the basin, and the 84% variance of the measured PFOS concentration was explained by two geographic variables, arterial traffic area and population. Source apportionment between point and nonpoint sources was conducted based on the results of the analysis. The contribution of PFOS from nonpoint sources was comparable to that from point sources in several major rivers flowing into Tokyo Bay. Source identification and apportionment using the GIS-based approach was shown to be effective, especially for ubiquitous types of pollution, such as PFC pollution. PMID:21885084

  4. Assessing metal toxicity in sediments using the equilibrium partitioning model and empirical sediment quality guidelines: A case study in the nearshore zone of the Bohai Sea, China

    International Nuclear Information System (INIS)

    Highlights: • Based on the EqP model, 35% samples had potential metal toxicity in sediments. • The empirical SQGs are not suitable for assessing sediment toxicity in Bohai Sea. • The EqP model is a much needed tool for metal toxicity assessment in coastal China. - Abstract: Surface sediments were collected from five nearshore (wastewater discharges, aquaculture facilities and a seaport) sites in Bohai Bay and Laizhou Bay, China. The equilibrium partitioning (EqP) model and empirical sediment quality guidelines (SQGs) were applied to assess the potential metal toxicity in the collected sediments. The results show that, based on the EqP model, 35% of stations exhibited potential metal toxicity. Several metals (Cu, Ni and Cr) exceeded the empirical SQGs (9–93% of the time), however these guidelines may not be suitable for use in the Bohai Sea owing to the background concentrations. The EqP model is a more useful method for assessing potential metal toxicity in Bohai Sea sediment than the empirical SQGs. Additionally, we have provided new understanding about methods for assessing sediment metal toxicity in the Bohai Sea that may be useful in other coastal areas in China

  5. Spatial distribution of dissolved Pb,Hg,Cd,Cu and As in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Characteristics of the spatial distribution of selected dissolved heavy metals were analyzed during large scale surveys from August 12 to 25.2003 in the Bohai Sea.Dissolved Pb was the only element with average concentrations higher than the grade-one sea water quality standard of China.The spatial distribution of dissolved Pb in surface water was similar to those of Cd,Cu and As,where the isopleths generally indicated decreasing values from the bays to the central areas.Only for Hg did the high concentrations not only appear in Liaodong Bay,Bohai Bay and Laizhou Bay,but also in the Central Area,viz.not only in inshore but also in offshore areas.Vertical distributions of dissolved Pb,Cd,Cu and As were largely uniform,while that of dissolved Hg increased with depth.We infer that the input of pollutants from land was the main influencing factor for the detected distribution patterns of dissolved heavy metals,followed by the dynamics of sea water,release from bottom sediments and biochemical processes.Comparing with historical data,average concentrations of dissolved heavy metals appear to decline in recent years.

  6. Study on eutrophication status and trend in Bohai Sea%渤海富营养化现状及趋势研究

    Institute of Scientific and Technical Information of China (English)

    于春艳; 梁斌; 鲍晨光; 李冕; 胡莹莹; 兰冬东; 许妍; 洛昊; 马明辉

    2013-01-01

    根据1997年、2000年、2005年和2010年四个时段的渤海海域水质监测资料,选用富营养化指数法对渤海海域的富营养化现状及变化趋势进行了评价.结果表明,2010年夏季呈富营养化状态的渤海海域面积约14 080 km2,重度富营养化海域主要集中在辽东湾、渤海湾及大连近岸.1997-2010年,渤海的富营养化状况逐渐恶化,总面积由110 km2增至14 080km2.辽东湾的富营养化程度和面积均呈加重趋势,至2010年已有大面积区域处于重度富营养化状态;位于渤海湾底部的天津近岸海域自2000年以来始终处于重度富营养化状态;大连近岸海域2010年出现了较严重的富营养化现象,尤其是复州湾和普兰店湾呈现较大面积的重度富营养化区域.%Based on the monitoring data in Bohai sea water quality in 1997 ,2000,2005, and 2010, using the eutrophication index method,the Bohai eutrophication status and changing trend were evaluated. The results showed that the Bohai area with eutrophication status was about 14 080 km2 in the summer of 2010,and severe eutrophication waters were mainly in the Liaodong Bay,Bohai Bay and Dalian coastal waters. From 1997 to2010,the Bohai eutrophication condition gradually deteriorated,and the total Bohai areas with eutrophication status were increased from 110 km2 to 14 080 km2. The eutrophication degree and area in Liaodong Bay showed the aggravating trend,and until 2010,a large area was in severe eutrophication status. The Tianjin coastal waters in the bottom in Bohai Bay always was a severe eutrophication status from 2000. The Dalian coastal waters appeared more serious eutrophication phenomenon in 2010,especially in the Fuzhou Bay and Pulandian Bay,showing a large area in the severe eutrophication area.

  7. Marine magnetic studies over a lost wellhead in Palk Bay, Cauvery Basin, India

    Digital Repository Service at National Institute of Oceanography (India)

    Ramana, M.V.; Subrahmanyam, V.; Sarma, K.V.L.N.S.; Seshavataram, B.T.V.

    Close grid marine magnetic surveys in the vicinity of a drill well site PH 9-1 in Palk Bay revealed that the area is characterized by smooth magnetic field except for a local anomaly caused by a lost wellhead. The smooth magnetic field is attributed...

  8. Air mass distribution and the heterogeneity of the climate change signal in the Hudson Bay/Foxe Basin region, Canada

    Science.gov (United States)

    Leung, Andrew; Gough, William

    2016-08-01

    The linkage between changes in air mass distribution and temperature trends from 1971 to 2010 is explored in the Hudson Bay/Foxe Basin region. Statistically significant temperature increases were found of varying spatial and temporal magnitude. Concurrent statistically significant changes in air mass frequency at the same locations were also detected, particularly in the declining frequency of dry polar (DP) air. These two sets of changes were found to be linked, and we thus conclude that the heterogeneity of the climatic warming signal in the region is at least partially the result of a fundamental shift in the concurrent air mass frequency in addition to global and regional changes in radiative forcing due to increases in long-lived greenhouse gases.

  9. 渤海湾表层沉积物各形态重金属的分布特征与生态风险评价%Variation Characteristics and Potential Ecological Risk Assessment of Heavy Metals in the Surface Sediments of Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    徐亚岩; 宋金明; 李学刚; 袁华茂; 李宁

    2012-01-01

    根据2008年春对渤海湾的调查,通过分级萃取的实验方法以及总量和分形态风险评价的手段,重点研究了渤海湾表层沉积物各形态重金属的分布特征、影响因素和潜在生态风险.结果表明,重金属在渤海湾中央的泥质区富集,自然来源是控制V、Ni、Cu、Pb、Co和Cd分布的主要因素,而Zn和Cr较易受环境变化或人为输入等影响,其中Pb作为大气沉降和陆源输入都存在的重金属,其受控因素与其他重金属有一定差异.形态分析表明,V、Zn和Cr以残渣态为主,Co、Ni和Cu则是可浸取态占优势.其中Co的可浸取态质量分数在A断面先增加后降低,Ni的可浸取态质量分数在海河口附近A3站达最大值(98.86%),Cu和Pb的可浸取态高值区出现在A断面的中央区域,优势形态是铁锰氧化物结合态,Cu在湾口的A10站降到最小值(43.83%),在黄河口的D1站达最大值(73.89%).风险评价表明,重金属总量富集因子由大到小:Pb〉Cd〉Zn〉Cr〉V〉Co〉Cu〉Ni,其中Pb、Cd和Zn的富集因子均大于1,但渤海湾沉积物总体质量良好,潜在生态风险较低.从形态角度评价,V和Cr基本无污染,Zn局部轻微污染,Co大部分轻度污染,Cu由无污染到中度污染,Ni由轻度污染到重度污染,Pb则属重度污染,其中Pb在渤海湾口A11站的P%(次生相与原生相分布比值)达1 329%.综合评价得出,Pb是渤海湾沉积物污染最严重的重金属,Cu和Zn有潜在污染,V、Cr和Co基本清洁.%The geochemical characteristics of eight heavy metals(Cd,Co,Cr,Cu,Ni,Pb,V and Zn) in two sediment cores from Bohai Bay,North China,were studied.Sediment samples were collected from 27 stations in spring 2008.A sequential extractions,procedure was used to gain their fractionation information.Five operationally defined fractions were obtained by this protocol,i.e.exchangeable(L1),bound to carbonates(L2),bound to Fe/Mn-oxides(L3),bound to organic matter

  10. Nontarget approach for environmental monitoring by GC × GC-HRTOFMS in the Tokyo Bay basin.

    Science.gov (United States)

    Zushi, Yasuyuki; Hashimoto, Shunji; Tanabe, Kiyoshi

    2016-08-01

    In this study, we developed an approach for sequential nontarget and target screening for the rapid and efficient analysis of multiple samples as an environmental monitoring using a comprehensive two-dimensional gas chromatograph coupled to a high resolution time-of-flight mass spectrometer (GC × GC-HRTOFMS). A key feature of the approach was the construction of an accurate mass spectral database learned from the sample via nontarget screening. To enhance the detection power in the nontarget screening, a global spectral deconvolution procedure based on non-negative matrix factorization was applied. The approach was applied to the monitoring of rivers in the Tokyo Bay basin. The majority of the compounds detected by the nontarget screening were alkyl chain-based compounds (55%). In the quantitative target screening based on the output from the nontarget screening, particularly high levels of organophosphorus flame retardants (median concentrations of 31, 116 and 141 ng l(-1) for TDCPP, TCIPP and TBEP, respectively) were observed among the target compounds. Flame retardants used for household furniture and building materials were detected in river basins where buildings and arterial traffic were dominated. The developed GC × GC-HRTOFMS approach was efficient and effective for environmental monitoring and provided valuable new information on various aspects of monitoring in the context of environmental management. PMID:27186689

  11. Freeliving marine nematodes as a pollution indicator of Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A hierarchical diversity index--taxonomic distinctnessindex +, which was first defined by Warwick and Clark in 1998, wasemployed to evaluate the pollution status of the Bohai Sea withfreeliving marine nematodes. The result showed that the Bohai Bayand other coastal sampling sites might be affected by oil and gasproduction and other anthropogenic influences. In other words,anthropogenic disturbance was affecting this component of thebenthos in these locations. And most offshore sampling sites in themiddle of the Bohai Sea were clear and unpolluted.

  12. Status and understanding of groundwater quality in the San Francisco Bay groundwater basins, 2007—California GAMA Priority Basin Project

    Science.gov (United States)

    Parsons, Mary C.; Kulongoski, Justin T.; Belitz, Kenneth

    2013-01-01

    Groundwater quality in the approximately 620-square-mile (1,600-square-kilometer) San Francisco Bay study unit was investigated as part of the Priority Basin Project of the Groundwater Ambient Monitoring and Assessment (GAMA) Program. The study unit is located in the Southern Coast Ranges of California, in San Francisco, San Mateo, Santa Clara, Alameda, and Contra Costa Counties. The GAMA Priority Basin Project is being conducted by the California State Water Resources Control Board in collaboration with the U.S. Geological Survey (USGS) and the Lawrence Livermore National Laboratory. The GAMA San Francisco Bay study was designed to provide a spatially unbiased assessment of the quality of untreated groundwater within the primary aquifer system, as well as a statistically consistent basis for comparing water quality throughout the State. The assessment is based on water-quality and ancillary data collected by the USGS from 79 wells in 2007 and is supplemented with water-quality data from the California Department of Public Health (CDPH) database. The primary aquifer system is defined by the depth interval of the wells listed in the CDPH database for the San Francisco Bay study unit. The quality of groundwater in shallower or deeper water-bearing zones may differ from that in the primary aquifer system; shallower groundwater may be more vulnerable to surficial contamination. The first component of this study, the status of the current quality of the groundwater resource, was assessed by using data from samples analyzed for volatile organic compounds (VOCs), pesticides, and naturally occurring inorganic constituents, such as major ions and trace elements. Water- quality data from the CDPH database also were incorporated for this assessment. This status assessment is intended to characterize the quality of groundwater resources within the primary aquifer system of the San Francisco Bay study unit, not the treated drinking water delivered to consumers by water

  13. 跨国公司造成东道国环境损害的环境侵权法律责任--从渤海湾蓬莱19-3油田溢油事故谈起%On Environmental Tort Liability of the Host Country’ s Environmental Damage Caused by the Multinationals:Starting from the Oil Spill of Penglai 19-3 Oil Field in Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    邬勇

    2014-01-01

    Currently ,the multinational companies are involved in international development and utilization of re -sources more frequently , and cases of causing damage to the environment of the host country is also increasing , such as the Bohai Bay oil spill , so that the topic as to how to determine the responsibility when a multinational causes environmental damage to the host country becomes a hot issue .Considering the social responsibility and environmental responsibility of multinational corporate , taking into account the special organizational structure of multinationals , with a view to protect the economic interests of multinationals so as to promote cross-border in-vestment as well as the environmental interests of the host country , the parent company of the multinational should bear against the supplemental liability for casuing damage to the environmental interests of the host coun -try.%当前,跨国公司参与国际资源开发利用活动越来越频繁,造成东道国环境损害的几率也越来越高,如渤海湾溢油事故。如何确定跨国公司对东道国造成环境损害的责任承担机制成为一个热门话题。从跨国公司企业的社会责任和环境公平责任出发,考虑到跨国公司特殊的组织结构形式,同时为了达到兼顾保护跨国投资者的经济利益和东道国的环境利益的目的,跨国公司母公司应承担侵害东道国环境利益的补充责任。

  14. Acoustic reflections in the water column of Krishna-Godavari offshore basin, Bay of Bengal.

    Science.gov (United States)

    Sinha, Satish K; Dewangan, Pawan; Sain, Kalachand

    2016-05-01

    Seismic oceanographic studies from various oceans worldwide have indicated that the acoustic reflections are mostly observed along thermal boundaries within the water column. However, the authors present a case study of seismic data from Krishna-Godavari Basin which shows that salinity variations also play an important role in the occurrence of water column reflections. The observed reflection is modeled using the reflectivity series derived from the salinity and temperature profiles from a nearby Conductivity-Temperature-Depth (CTD) location. Sensitivity analysis of temperature and salinity on soundspeed shows that the effect of salinity cannot be ignored for modeling acoustic reflections. The synthetic seismogram matches well with the observed reflection seismic data. Remarkable similarities between the reflection seismic and the salinity profile in the upper thermocline suggest the importance of salinity variations on the water column reflection. Furthermore, impedance inversion of the reflectivity data reveals several thermohaline structures in the water column. The origin of these thermohaline structures is largely unaddressed and may be attributed to the fresh water influx coming from Himalayan and Peninsular rivers or due to the presence of different water masses in the Indian Ocean which warrants a detailed study using concurrent seismic and CTD data.

  15. Acoustic reflections in the water column of Krishna-Godavari offshore basin, Bay of Bengal.

    Science.gov (United States)

    Sinha, Satish K; Dewangan, Pawan; Sain, Kalachand

    2016-05-01

    Seismic oceanographic studies from various oceans worldwide have indicated that the acoustic reflections are mostly observed along thermal boundaries within the water column. However, the authors present a case study of seismic data from Krishna-Godavari Basin which shows that salinity variations also play an important role in the occurrence of water column reflections. The observed reflection is modeled using the reflectivity series derived from the salinity and temperature profiles from a nearby Conductivity-Temperature-Depth (CTD) location. Sensitivity analysis of temperature and salinity on soundspeed shows that the effect of salinity cannot be ignored for modeling acoustic reflections. The synthetic seismogram matches well with the observed reflection seismic data. Remarkable similarities between the reflection seismic and the salinity profile in the upper thermocline suggest the importance of salinity variations on the water column reflection. Furthermore, impedance inversion of the reflectivity data reveals several thermohaline structures in the water column. The origin of these thermohaline structures is largely unaddressed and may be attributed to the fresh water influx coming from Himalayan and Peninsular rivers or due to the presence of different water masses in the Indian Ocean which warrants a detailed study using concurrent seismic and CTD data. PMID:27250139

  16. Biomass of meiobenthic in the Bohai Sea, China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A grid of 22 stations, giving a broad geographic coverage of the Bohai Sea and the Bohai Strait was selected. Undisturbed sediments were collected from sampling stations during cruises in June 1997, in September/October 1998 and again in April/May 1999. Based on the results of Juario (1975),the average biornass, 0.404 g/(m2@ a) of meiofauna (including nematode, harpacticoida, bivalve larvae,polycheata and kinorhyncha) in the Bohai Sea is given and accounts for 4.5 percent of the macrofauna in the Bohai Sea. The horizontal distribution of the biomass of meiofauna showed that it was higher at the stations of middle east part of the Bohai Sea and the strait in 1998 and 1999 cruises and it decreased at the stations near to the strait mouth and increased at Station B1 in 1999 cruise. The annual average pro duction in the Bohai Sea is 3. 636 g/m2 calculated in term of the formula P = 9B. Compared with the biomass of other sea areas in the world, the biomass of the Bohai Sea is similar but slightly lower. The individual average dry weight of nematodes given by different authors is analyzed.

  17. Investigation on Enteromorpha in Bohai Sea%渤海浒苔属绿藻调查

    Institute of Scientific and Technical Information of China (English)

    刘正一; 刘海燕; 赵玉山; 刘兆普; 秦松

    2011-01-01

    于2009年至2010年对渤海及其周边10个沿海城市和6个岛屿的浒苔属绿藻进行了调查,初步确定该海区缘管浒苔、肠浒苔、扁浒苔、浒苔、条浒苔 5个种类的地理分布情况.并对生物量进行了评估.与历史资料相比,渤海中辽东湾、渤海湾和莱州湾三个湾内的浒苔多样性和生物量下降明显或保持较低水平,湾周边地区则维持较高水平.此外,在近海人工基质上,以浒苔属为主的绿藻相对于红藻、褐藻分布更为广泛.%Through the investigations in 10 coastal cities and 6 islands from 2009 to 2010, 5 species of Enteromorpha distributed in Bo-hai Sea were preliminarily ascertained, I. E. E. Linza, E. Intestinalis, E. Compressa, E. Prolifera and E. Clathrata. In this paper, ge ographical distribution and biomass of these species have been preliminary researched. Compared with historical records, the diversity and biomass of Enteromorpha decreased obviously or remained a low level in the 3 bays of Bohai Sea while kept a high level in the area near Bohai Sea. Besides, the green algae mainly of Enteromorpha distributed more widely than red algae and brown algae on the coastal artificial buildings.

  18. Trends in Surface-Water Nitrate-N Concentrations and Loads from Predominantly-Forested Watersheds of the Chesapeake Bay Basin

    Science.gov (United States)

    Eshleman, K. N.

    2011-12-01

    important (and under-appreciated) role in improving water quality throughout the Bay watershed. A second interesting finding was that the statistically significant reductions in annual nitrate-N concentration at the Potomac River RIM station could be entirely explained by commensurate improvements at the upstream (Hancock) station; in fact, no trend in nitrate-N concentration associated with the eastern portion of the basin was found (after subtracting out the influence of the upstream portion). Additional research is needed to understand why nitrogen retention by forested lands may be increasing and thus helping restore water quality throughout the Chesapeake Bay watershed. The results also have obvious implications for meeting local water quality goals as well as the basin-wide goal of the Chesapeake Bay TMDL for nitrogen.

  19. Benthic habitat classification in Lignumvitae Key Basin, Florida Bay, using the U.S. Geological Survey Along-Track Reef Imaging System (ATRIS)

    Science.gov (United States)

    Reich, C.D.; Zawada, D.G.; Thompson, P.R.; Reynolds, C.E.; Spear, A.H.; Umberger, D.K.; Poore, R.Z.

    2011-01-01

    The Comprehensive Everglades Restoration Plan (CERP) funded in partnership between the U.S. Army Corps of Engineers, South Florida Water Management District, and other Federal, local and Tribal members has in its mandate a guideline to protect and restore freshwater flows to coastal environments to pre-1940s conditions (CERP, 1999). Historic salinity data are sparse for Florida Bay, so it is difficult for water managers to decide what the correct quantity, quality, timing, and distribution of freshwater are to maintain a healthy and productive estuarine ecosystem. Proxy records of seasurface temperature (SST) and salinity have proven useful in south Florida. Trace-element chemistry on foraminifera and molluscan shells preserved in shallow-water sediments has provided some information on historical salinity and temperature variability in coastal settings, but little information is available for areas within the main part of Florida Bay (Brewster-Wingard and others, 1996). Geochemistry of coral skeletons can be used to develop subannually resolved proxy records for SST and salinity. Previous studies suggest corals, specifically Solenastrea bournoni, present in the lower section of Florida Bay near Lignumvitae Key, may be suitable for developing records of SST and salinity for the past century, but the distribution and species composition of the bay coral community have not been well documented (Hudson and others, 1989; Swart and others, 1999). Oddly, S. bournoni thrives in the study area because it can grow on a sandy substratum and can tolerate highly turbid water. Solenastrea bournoni coral heads in this area should be ideally located to provide a record (~100-150 years) of past temperature and salinity variations in Florida Bay. The goal of this study was to utilize the U.S. Geological Survey's (USGS) Along-Track Reef Imaging System (ATRIS) capability to further our understanding of the abundance, distribution, and size of corals in the Lignumvitae Key Basin. The

  20. 冬季覆海冰对台田盐渍土壤水分和盐分的影响%Effects of Covering Sea Ice on Platform Field on Soil Water and Salt Content in Coastal Saline Soil of Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    陶军; 顾卫; 林叶彬; 许映军; 卜丹阳

    2011-01-01

    Based on the building technology of platform field, sea ice was covered on soil surface of the field in Bohai Bay of China, because sea ice had lower salts than seawater in winter.The change of soil water and salt in melting processes of sea ice was determined at different stages.The present studies showed that the large amount of ice-melting water infiltrated into the soil and increased soil water content at all depths, especially top soil (0-20 cm).In later stages, soil water content of 0-40 cm layer was reduced with increasing of air temperature and value of other soil layers stabilized.At March 8, soil salt content of 0-20 cm and 20 -40 cm layer were lower 70% and 22.22% than the value at primary time, whereas soil salt content of other layers slightly increased.At March 14, sea ice was completely melt and soil salt content of all layers continued to decrease in platform field.During later sampling stages, soil salt content of 0-20 cm and 20-40 cm layer stabilized (1.5~2.0 g/kg and 3.5%, respectively) and soil desalting rate of them was 80%~85% and 22.22 %, respectively.While soil salt content of deeper layer had no changes compared to their value of primary time.These results indicated that the combination of platform field and covering sea ice on soil surface decreased 0-40 cm layer soil salt content and there was no salt accumulation in deeper soil layers.%在渤海湾滨海地区,以台田修建技术为基础,将冬季海水(或咸水)冻结而形成较低盐度的海冰(或咸水冰)覆盖至台田土壤表面.研究覆冰的融化过程中台田土壤水分和盐分的时空变化.结果表明:随着覆冰融化,大量的冰融水进入土壤,台田不同土层土壤的含水量得到增加,尤其是表层土壤.当覆冰完全融化,气温的上升,台田0-20 cm土壤含水量迅速降低,而深层土壤的含水量趋于稳定.在覆冰完全融化前(3月8日),0-20 cm和20-40 cm土壤含盐量较初始值分别降低了70%和22.22%;

  1. Lacustrine Basin Slope Break — A New Domain of Strata and Lithological Trap Exploration

    Institute of Scientific and Technical Information of China (English)

    WangYingmin; LiuHao; XinRenchen; JinWudi; WangYuan; LiWeiguo

    2004-01-01

    Based on the studies of the Songliao Basin characterized by Cretaceous down-warping, of the Jurassic compressional flexural Junggar basin and of the Bohai Bay Basin characterized by Paleogene rifting, the multiple-grades slope break has developed in lacustrine basins of different origins. Their genetic types can be divided into tectonic slope break, depositional slope break and erodent slope break. The dominant agent of the slope break is tectogenesis, and the scale of slope breaks relates with the size of tectogenesis. The results of the study show that control of mutual grades slope breaks on atectonic traps mainly represent: 1) Atectonic traps develop close to mutual grades slope breaks, with beads-shaped distribution along the slope breaks. 2) In the longitudinal direction, the development of atectonic traps is characterized by the inheritance. 3) Different slope breaks and their different geographical positions can lead to different development types of atectonic traps. 4) A slope break can form different kinds of atectonic traps because of its great lateral variation. 5) The existence of mutual-grade slope breaks leads to different responses of erosion and deposition at different geographical positions in the basin. The oil source bed, reservoir and cap rock combination of atectonic traps is fine. 6) The oil-bearing condition of atectonic traps controlled by slope breaks is very favorable.

  2. Model study on Bohai ecosystem 2. Annual cycle of nutrient-phytoplankton dynamics

    Institute of Scientific and Technical Information of China (English)

    LIU Hao; YIN Baoshu

    2006-01-01

    Using the coupled bio-physical model described in the first paper of this series of studies, the annual variations of algae biomass and nutrient concentration in the Bohai Sea are simulated. Modeled results show that the onset of spring bloom is induced by high nutrient stocks stored in winter, though the initial time is earlier in shallow waters than in deep waters, for which the evolution of the vertical stratification in deep waters plays an important role; on the other hand, newly added river-borne nutrients and resuspending sediment-borne nutrients are responsible for the outburst of autumn blooms. On the basis of modeled results, it is also found that the BS ecosystem, as a whole, is limited by nitrogen all the year round, though the phosphorus limitation is apparent in the Laizhou Bay where the ratio of nitrogen concentration to phosphorus concentration is higher than 16 due to the contribution of newly added nutrient species from Huanghe River discharges.

  3. The Kara Bogaz Gol Bay, Lake Issyk Kul and Aral Sea sediments as archives of climate change in the Aral-Caspian catchment basin

    International Nuclear Information System (INIS)

    A 5-m long core of bottom sediments from the Kara Bogaz Gol Bay of the Caspian Sea, 4- m and 2-m cores from the Issyk Kul Lake of the Thian Shan Mountains, and a 4-m core from the Aral Sea were examined for evidence of climatic and environmental changes in the catchment basin of the Central Asia Region. The distribution of 18O and 13C in the bulk carbonates, 2H in the pore water, radiocarbon age, oxygen and hydrogen isotopes in the lake water, abundance of CaCO3, MgCO3, and the basic salt ions of Na+, K+, Cl-, SO42- in the cores were measured. The isotope and hydrogeochemical data of the Kara Bogaz Gol Bay sediments prove a historical scenario for the basin which suggests that fresh water has been discharged to the Caspian Sea during the Bay's humid episode across the Central Asia Region (∼ 9 Ka BP). Isotope and geochemical evidence indicate that the sedimentation of the upper core segment has taken place during the last ∼2.2 Ka BP in the environment of sea water recharged from the Central Caspian Basin. The period of between 4.3 and 6 Ka BP, which relates to the core depth interval of between 170 cm and 260 cm, demonstrates the most dramatic change in the sedimentation rate in the Issyk Kul Lake. It means that active melting of the mountain glaciers and warming of climate has happened just in this period. The swamp plant peat layers at depths of 230 cm and 130 cm indicate that during 3.5-3.7 Ka BP and 1.6-1.8 Ka BP the Aral Sea dried and broke up into a number of lakes and swamps. Sediment cores taken from the bottom of the Kara Bogaz Gol Bay, Lake Issyk Kul and Aral Sea show periodic rise and fall in water levels during the last ∼10 000 years. Two peat layers within the sediment core of the Aral Sea and dated at 1.6-1.8 Ka BP and 3.5-3.7 Ka BP demonstrate that this reservoir also periodically dried. (author)

  4. Air Pollution Over the Ganges Basin and Northwest Bay of Bengal in the Early Postmonsoon Season Based on NASA MERRAero Data

    Science.gov (United States)

    Kishcha, Pavel; Da Silva, Arlindo M.; Starobinets, Boris; Alpert, Pinhas

    2014-01-01

    The MERRA Aerosol Reanalysis (MERRAero) has been recently developed at NASA's Global Modeling Assimilation Office. This reanalysis is based on a version of the Goddard Earth Observing System-5 (GEOS-5) model radiatively coupled with Goddard Chemistry, Aerosol, Radiation, and Transport aerosols, and it includes assimilation of bias-corrected aerosol optical thickness (AOT) from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor on both Terra and Aqua satellites. In October over the period 2002-2009, MERRAero showed that AOT was lower over the east of the Ganges basin than over the northwest of the Ganges basin: this was despite the fact that the east of the Ganges basin should have produced higher anthropogenic aerosol emissions because of higher population density, increased industrial output, and transportation. This is evidence that higher aerosol emissions do not always correspond to higher AOT over the areas where the effects of meteorological factors on AOT dominate those of aerosol emissions. MODIS AOT assimilation was essential for correcting modeled AOT mainly over the northwest of the Ganges basin, where AOT increments were maximal. Over the east of the Ganges basin and northwest Bay of Bengal (BoB), AOT increments were low and MODIS AOT assimilation did not contribute significantly to modeled AOT. Our analysis showed that increasing AOT trends over northwest BoB (exceeding those over the east of the Ganges basin) were reproduced by GEOS-5, not because of MODIS AOT assimilation butmainly because of the model capability of reproducing meteorological factors contributing to AOT trends. Moreover, vertically integrated aerosol mass flux was sensitive to wind convergence causing aerosol accumulation over northwest BoB.

  5. The impact of urban expansion and agricultural legacies on trace metal accumulation in fluvial and lacustrine sediments of the lower Chesapeake Bay basin, USA.

    Science.gov (United States)

    Coxon, T M; Odhiambo, B K; Giancarlo, L C

    2016-10-15

    The progressively declining ecological condition of the Chesapeake Bay is attributed to the influx of contaminants associated with sediment loads supplied by its largest tributaries. The continued urban expansion in the suburbs of Virginia cities, modern agricultural activities in the Shenandoah Valley, the anthropogenic and climate driven changes in fluvial system hydrodynamics and their potential associated impacts on trace metals enrichment in the bay's tributaries necessitate constant environmental monitoring of these important water bodies. Eight (210)Pb and (137)Cs dated sediment cores and seventy two sediment grab samples were used to analyze the spatial and temporal distributions of Al, Ca, Mg, Cr, Cd, As, Se, Pb, Cu, Zn, Mn, and Fe in the waterways of the Virginia portion of the Chesapeake Bay basin. The sediment cores for trace metal historical fluctuation analysis were obtained in lower fluvial-estuarine environments and reservoirs in the upper reaches of the basin. The trace metal profiles revealed high basal enrichment factors (EF) of between 0.05 and 40.24, which are interpreted to represent early nineteenth century agricultural activity and primary resource extraction. Surficial enrichment factors on both cores and surface grab samples ranged from 0.01 (Cu) to 1421 (Cd), with Pb, Cu, Zn, and Cd enrichments a plausible consequence of modern urban expansion and industrial development along major transportation corridors. Contemporary surficial enrichments of As, Se, and Cr also ranged between 0 and 137, with the higher values likely influenced by lithological and atmospheric sources. Pearson correlation analyses suggest mining and agricultural legacies, coupled with aerosol deposition, are responsible for high metal concentrations in western lakes and headwater reaches of fluvial systems, while metal accumulation in estuarine reaches of the major rivers can be attributed to urban effluence and the remobilization of legacy sediments. PMID:27310532

  6. Distribution and sources of organic matter in surface sediments of Bohai Sea near the Yellow River Estuary, China

    Science.gov (United States)

    Liu, Dongyan; Li, Xin; Emeis, Kay-Christian; Wang, Yujue; Richard, Pierre

    2015-11-01

    Total organic carbon (TOC) and total nitrogen (TN) concentrations and C and N stable isotope compositions in 64 surface sediment samples from the mouth of the Yellow River (YR) and from the Bohai Sea (BS) outline the distribution and sources (terrestrial and marine) of sediment organic matter. Comparatively high TOC (0.5-0.9%) and TN (0.07-0.11%) concentrations in the Central BS correlate with fine-grained sediments that contain high concentrations of algal-derived organic carbon (AOC) and biogenic silica (BSi). Together, they indicate a dominant contribution of autochthonous organic matter from marine primary production. Low TOC (AOC and BSi contents. δ13C values (-21 to -22‰) are characteristic of marine-derived organic carbon in the Central BS and the Bohai Strait, whereas a significant terrigenous contribution of 40-50% is indicated by lower values (<-23‰) near the YR mouth. The spatial pattern of rising δ13C from the YR mouth to offshore areas indicates rapid sedimentation of fluvial suspensions within the vicinity of the river mouth and in Laizhou Bay, so that only approximately 10-20% of YR-derived sediments are transported to and deposited in the Central BS and/or the Bohai Strait. At most sites, δ15N values are in the typical range of marine organic matter produced from assimilation of marine nitrate by phytoplankton (5-5.5‰), but some relatively high values (6-7.28‰) mark the southern area of the Laizhou Bay as a significant sink of anthropogenic nitrogen.

  7. Characteristics and Oil-source Investigation of the Oils in the Nanpu Oilfield,Bohai Bay Basin%渤海湾盆地南堡油田原油特征与油源分析

    Institute of Scientific and Technical Information of China (English)

    万中华; 李素梅

    2011-01-01

    Nanpu oilfield is a recently discovered field with substantial petroleum reserves. Totally 43 oils and 31 rock samples were collected for performing detailed geochemical analyses to unravel the characteristics and oil source for the oils. Three oil families have been recognized according to biomarkers and compound specific carbon isotope of n-alkanes, namely Tertiary oils in No. 1 and 2 structural belts (OF- Ⅰ ) , Tertiary oils in No. 3, 4 and 5 structural belts ( OF- Ⅱ ) and Ordovician oils ( OF- Ⅲ ). The OF- Ⅰ is characterized by relatively low ratios of diasteranes to regular steranes but high ratios of steranes to hopanes , 4-methyl steranes to C29regular steranes and gammacerane to C30 hopane with a little heavier δ13C values of the compound specific isotope of n-alkanes relative to the OF- Ⅱ. The OF-Ⅲ is distinguished from both the OF- Ⅰ and OF- Ⅱ with relatively higher thermal maturity and heavier δ13C values of n-alkanes. Detailed oil-source rock correlation showed that the OF- Ⅱ and OF-Ⅲ were mainly derived from the source rocks of Ed3 - Es1 and Es2+3 respectively, and the OF-Ⅰ was derived from both the Es2+3 and Ed3 - Es1 source rocks. We suggested that the Es2+3 is one of the most important source rocks of the Tertiary oils in the Nanpu oilfield , which is different from the previous idea that only the Ed3 - Es1 is responsible for the Tertiary oils. This study should be helpful to petroleum resources evaluation and further petroleum exploration of the Nanpu oilfield.%南堡油田是渤海湾盆地近年发现的油气储量可观的新油田,为揭示该油田原油特征与成因,对43个原油样品、31块泥岩样品进行详细的地球化学研究与油源对比.依据特征生物标志物、单体烃碳同位素分析,将南堡油田原油分为3种类型:I类,南堡1、2号构造带古近系+新近系原油;Ⅱ类,南堡3、4、5号构造带古近系+新近系原油;Ⅲ类,南堡凹陷已发现奥陶系潜山原油.Ⅰ类原油以较低的重排甾烷/规则甾烷,较高的甾烷/藿烷、4-甲基甾烷/C29规则甾烷、伽马蜡烷/C30藿烷值及正构烷烃单体烃碳同位素相对偏重等特征区别于Ⅱ类原油;Ⅲ类原油以较高成熟度、正构烷烃单体烃碳同位素总体偏重等特征不同于Ⅰ、Ⅱ类原油.油源对比结果表明,Ⅰ类原油为沙二+三段、东三段-沙一段烃源岩的混合贡献,Ⅱ类原油主要来源于东三段一沙一段烃源岩,Ⅲ类原油主要来源于沙二+三段烃源岩.首次明确提出南堡1、2号构造带古近系+新近系原油主要为沙二+三段烃源岩的成烃贡献,沙二+三段烃源岩为南堡油田主力烃源岩之一,这对南堡油田油气资源评价和勘探方向决策具有参考意义.

  8. 渤海湾盆地青东凹陷古近系烃源岩生烃潜力分析%Analysis of eogene carbonate in Shahejie formation in Qing dong sag,Bohai bay basin

    Institute of Scientific and Technical Information of China (English)

    王勇; 杨萍

    2011-01-01

    Based on the analyses of such parameters as total organic carbon,S1+S2,IH, Tmax,Ro and the like,organic abundance,organic types and organic maturity of Eogene hydrocarbon source rock in Qingdong Sag have been studied.Sha3,Sha4 produced good-better hydrocarbon source rock.The types of hydrocarbon source rock of Dongyin formation, Sha1,sha2 mainly comprises typeⅢand typeⅡ,while Sha3,sha4 mainly comprise typeⅠand typeⅡ1.The carbonate source rock of Sha3,Sha4 has stepped into low-mature to mature phases,fairly capable of producing hydrocarbon.%通过分析已有样品的有机碳含量、生烃潜量、氢指数、最大热解温度及镜质体反射率Ro等参数,对青东凹陷古近系烃源岩有机质丰度、有机质类型和有机质成熟度进行研究。该区沙三段、沙四段为好-非常好的烃源岩,东营组、沙一段、沙二段烃源岩类型以腐殖型(Ⅲ型)和混合型(Ⅱ型)为主,而沙三段、沙四段烃源岩类型主要为腐泥型(Ⅰ型)和混合型(Ⅱ1型)。沙三段、沙四段烃源岩,已进入低熟-成熟期,具有较强的生烃能力。

  9. 渤海湾盆地中原地区古地温梯度恢复研究%Reconstruction of the paleogeothermal gradient in the Zhongyuan area, Bohai Bay basin, East China

    Institute of Scientific and Technical Information of China (English)

    姚合法; 任玉林; 申本科

    2006-01-01

    渤海湾盆地中新生代具有叠合盆地多期叠加演化的特点,不同地质时期地温场的恢复具有多解性和不确定性.应用包裹体测温、磷灰石裂变径迹分析、Barker温度函数法、EASY%Ro模拟等方法,通过不同构造单元的最高古地温的恢复,进行不同地质时期的地温梯度恢复.研究表明:(1)包裹体测温、磷灰石裂变径迹分析、Barker温度函数等方法仅适用于欠补偿沉积区古地温及古地温梯度恢复;(2)Barker法计算的地温梯度偏高;(3)而EASY%Ro热史模拟方法是补偿-近补偿沉积区古地温梯度恢复的有效方法;(4)三叠纪、侏罗-白垩纪、古近纪是影响上古生界烃源岩演化的关键时期,地温梯度分别为3.3 ℃/100 m、4.5 ℃/100 m和4.0 ℃/100 m.

  10. DISTRIBUTION AND POPULATION DYNAMICS OF PARACALANUS PARVUS, PARACALANUS CRASSIROSTRIS, AND ACARTIA BIFILOSA (COPEPODA, CALANOIDA) IN THE BOHAI SEA

    Institute of Scientific and Technical Information of China (English)

    王荣; 张鸿雁; 王克; 左涛

    2002-01-01

    Paracalanus parvus, Paracalanus crassirostris, and Acartia bifilosa ar e dominant and widely distributed in the Bohai Sea, and comprise an important part of zooplankton in terms of biomass as well as production rate. In order to understa nd their seasonal distribution and population dynamics, their stage-specific abund ance in different months of the year were analyzed based on the never analyzed yet sa mples collected in 1959. The three species showed clear and remarkable seasonal variat ion in abundance, which maximized in spring and summer, when they formed high biomas s patches or concentrations in the nearshore area. For Paracalanus parvus, two peaks were observed in the annual circle, one in June and the other in September. For Paracalanus crassirostris, one peak occurred in summer and a small one in De cember. The seasonal pattern of Acartia bifilosa was different in different regions. In Bohai Bay it had a two-peak pattern, with the first large peak occurring in May and t he second one in October. In Laizhou Bay, a winter peak in December and January cou ld be observed besides the spring one. The number of generations during the reprodu ctive season for the three species was estimated based on the annual cycle in abundanc e and ambient temperature.

  11. Regional carrying capacity: case studies of Bohai Rim area

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Carrying capacity research has been carried out for a long time. However, synthesized carrying capacity researches based on systematic views began only in the 1970s. There is even less work done in China. This paper tries to address both synthesized carrying capacity research and its utilization in China. State spaces method from the systematic science was borrowed to construct the conceptual model of regional carrying capacity. Based on the conceptual model and the surveys in the Bohai Rim area, we construct a representative indicators system for quantifying regional carrying capacity in the Bohai Rim. While employing system dynamic models we simulated the evolving trend of both the regional carrying states and regional carrying capacity from 1999 to 2015. The results proved the statement that Bohai Rim is overall over-capacity for a long time and will be over-capacity in the foreseeable future. Among all the restriction factors, water shortage and environmental pollution stand out to be the two primary obstacles for Bohai Rim's sustainable development.Regional differentiation analysis further indicates that coastal areas of the Bohai Rim burden more than its overall level. However, Shandong province shows some good signs in addressing the regional carrying capacity issues. The research is successful in addressing the quantification of regional carrying capacity issues, but nonetheless it needs further refinery and more information.

  12. Hydrocarbons in the Bay of Bengal and Central Indian Basin bottom sediments: Indicators of geochemical processes in the lithosphere

    Digital Repository Service at National Institute of Oceanography (India)

    Chernova, T.G.; Paropkari, A.L.; Pikovskii, Yu.I.; Alekseeva, T.A.

    that the hydrocarbons are mostly derived from marine sources. Sharp increases fo hydrocarbons are found in the vicinity of the tectonically active region of the Central Indian Basin, particularly in the sediments collected from the fracture zone. The total concentration...

  13. A model study on seasonal spatial-temporal variability of the Lagrangian Residual Circulations in the Bohai Sea%渤海风驱-潮致Lagrange余流的数值模拟与季相时空变异

    Institute of Scientific and Technical Information of China (English)

    李国胜; 王海龙; 李柏良

    2005-01-01

    The spatial distribution and seasonal variation of the tide-induced Lagrangian Residual Circulations (LRC hereafter), wind-driven LRC, and the coupling dynamic characteristics were simulated using ECOM, given the Hellerman and Rosenstein global monthly-mean wind stresses. The results showed that the tide-induced LRC of the harmonic constituent M2 bears an identical pattern in four seasons in the Bohai Sea: the surface one is weak with random directions; however, there exist a southeast current from the Bohai Strait to the Laizhou bay, and a weakly anticlockwise gyre in the south of the Bohai Strait for the bottom layer LRC. The magnitude of bottom layer tide-induced LRC is larger than the surface one, and moreover, it contributes significantly to the whole LRC in the Bohai Sea. Unlike the identical structure of the tide-induced LRC, the wind driven LRC varies seasonally under the prevailing monsoon. It forms a distinct gyre under the summer and winter monsoons in July and January respectively, but it seems weak and non-directional in April and September.

  14. Toxic Algae and Early Warning Management in Yellow Sea and Bohai Sea of China

    Institute of Scientific and Technical Information of China (English)

    Song; Lun; Song; Guangjun; Song; Yonggang; Xu; Xiaohong

    2014-01-01

    The research status of toxic algae in Yellow Sea and Bohai Sea are reviewed from the aspects of toxicity characteristics,toxic mechanism and early warning management,and the existing toxic algae and their toxicity in Yellow Sea and Bohai Sea are analyzed in the paper. The early warning level of toxic algae in Yellow Sea and Bohai Sea of China is put forward,and the research direction of shellfish poisoning in future is summarized.

  15. Subsidence history and forming mechanism of anomalous tectonic subsidence in the Bozhong depression, Bohaiwan basin

    Institute of Scientific and Technical Information of China (English)

    XIE; XiNong

    2007-01-01

    Asia.In:Hall R,Blundell D J,eds.Tectonic Evolution of Southeast Asia.London,Geological Society,1996,153-184[15]Lu B G.Atlas of Typical Seismic Sections in China (in Chinese).Beijing:Petroleum Industry Press,1991.260[16]Chen W P,Nabelek J.Seismogenic strike-slip faulting and the development of the North China Basin.Tectonics,1988,7:975-989[17]Gong Z S.Neotectonics and petroleum accumulation in offshore Chinese basins.Earth Sci-J China Univ Geosci (in Chinese),2004,29(5):513-517[18]Zhang G C,Zhu W L,Shao L.Pull-apart tectonic and hydrocarbon prospecting in Bohai bay and its nearby area.Acta Pet Sin (in Chinese),2001,22(2):14-18[19]Lithgow-Bertelloni C,Gurnis M.Cenozoic subsidence and uplift of continents from time-varying dynamic topography.Geology,1997,25(8):735-738[20]Wheeler P,White N.Quest for dynamic topography:Observations from Southeast Asia.Geology,2000,28 (11):963-966[21]Gurnis M.Rapid continental subsidence following the initiation and evolution of subduction.Science,1992,255:1556-1558[22]Steinberger B,Sutherland R,O'Connell R J.Prediction of Emperor-Hawaii seamount locations from a revised model of global plate motion and mantle flow.Nature,2004,430:167-173

  16. Distributions of dimethylsulfide in the Bohai Sea and Yellow Sea of China

    Institute of Scientific and Technical Information of China (English)

    HU Min; TANG Xiao-yan; LI Jin-long; MA Qi-ju

    2003-01-01

    Dimethylsulfide(DMS) measurements in the surface seawater of China eastern coastline were conducted during March 9-10, 1993 in Bohai Sea along the cruise from Dalian to Tianjin and during September 24-25, 1994 in Yellow Sea along the cruise from Shanghai to Qingdao. On the cruise in Bohai Sea DMS concentrations varied from 0. 11 to 2.63 nmol/L with an average of 1.31 nmol/L, while DMS flux Bohai Sea. DMS concentrations and fluxes had a similar spatial trend both in Bohai Sea and Yellow Sea with the correlation coefficients of 0.75 and 0.64, respectively.

  17. Applied Sequence Stratigraphy in Nonmarine Basin of China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    basin, the step-faulting breaks controlled the depositional system. Usually, the low-stand complex fan, prograding wedge and high-stand turbidity fan were close to the third stepping break. In the low-stand period, the sediments went around the incised valleys which then were filled with sand bar near the second stepping break. At the first stepping break the sediments were bypassed step by step or the alluvial fan was deposited with forced regressions in the low-stand time. The low-stand wedge may serve as favorable subtle or complex traps at the basin floor fan. The economic effectiveness is measured with the borehole in Bohai Bay basin.

  18. Wave Characteristics and Extreme Parameters in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi-feng; WU Ke-jian; ZHOU Liang-ming; WU Lun-yu

    2012-01-01

    This paper is aimed at the whole Bohai Sea,as the complement and improvement of wave characteristics and extreme parameters.Wave fields were simulated in the Bohai Sea by using wave model SWAN from 1985 to 2004.The input data based on the hindcast of high-resolution wind fields from RAMS and water level fields from POM,which have been tested and verified well.Comparisons of significant wave heights between simulation and station observations show a good agreement in general.By statistical analysis,the wave characteristics such as significant wave heights,dominant wave directions and their seasonal variations are discussed.In addition,main wave extreme parameters and directional extreme values particularly for 100-year return period are investigated.

  19. Depositional dynamics in a river diversion receiving basin: The case of the West Bay Mississippi River Diversion

    Science.gov (United States)

    Kolker, Alexander S.; Miner, Michael D.; Weathers, H. Dallon

    2012-06-01

    River deltas are a globally distributed class of sedimentary environment that are highly productive, ecologically diverse and serve as centers for population and commerce. Many deltas are also in a state of environmental degradation, and the Mississippi River Delta (MRD) stands out as a particularly iconic example. Plans to restore the MRD call for partially diverting the Mississippi River, which should reinitiate natural deltaic land-building processes. While the basic physical underpinnings of river diversions are relatively straightforward, there exists a considerable controversy over whether diversions can and do deliver enough sediment to the coastal zone to build sub-aerial land on restoration-dependent time scales. This controversy was addressed through a study of crevasse-splay dynamics at the West Bay Mississippi River Diversion, the largest diversion in the MRD that was specifically constructed for coastal restoration. We found that most sediments were distributed over a 13.5 km area, with the maximum deposition occurring at the seaward end of this field. These results indicate substantial sediment deposition downstream of project boundaries and run counter to simple sedimentary models, which predict that maximum sediment deposition should occur closest to the riverbank. Despite this, most sediments appear to be retained in the nearshore zone, suggesting that the sediment retention efficiency was at the higher end of the 30-70% range suggested by some sediment budgets.

  20. Simulation of climate change in San Francisco Bay Basins, California: Case studies in the Russian River Valley and Santa Cruz Mountains

    Science.gov (United States)

    Flint, Lorraine E.; Flint, Alan L.

    2012-01-01

    As a result of ongoing changes in climate, hydrologic and ecologic effects are being seen across the western United States. A regional study of how climate change affects water resources and habitats in the San Francisco Bay area relied on historical climate data and future projections of climate, which were downscaled to fine spatial scales for application to a regional water-balance model. Changes in climate, potential evapotranspiration, recharge, runoff, and climatic water deficit were modeled for the Bay Area. In addition, detailed studies in the Russian River Valley and Santa Cruz Mountains, which are on the northern and southern extremes of the Bay Area, respectively, were carried out in collaboration with local water agencies. Resource managers depend on science-based projections to inform planning exercises that result in competent adaptation to ongoing and future changes in water supply and environmental conditions. Results indicated large spatial variability in climate change and the hydrologic response across the region; although there is warming under all projections, potential change in precipitation by the end of the 21st century differed according to model. Hydrologic models predicted reduced early and late wet season runoff for the end of the century for both wetter and drier future climate projections, which could result in an extended dry season. In fact, summers are projected to be longer and drier in the future than in the past regardless of precipitation trends. While water supply could be subject to increased variability (that is, reduced reliability) due to greater variability in precipitation, water demand is likely to steadily increase because of increased evapotranspiration rates and climatic water deficit during the extended summers. Extended dry season conditions and the potential for drought, combined with unprecedented increases in precipitation, could serve as additional stressors on water quality and habitat. By focusing on the

  1. 渤中部底质沉积物重金属环境质量%Environmental quality of heavy metals in surface sediments in the central region of the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    刘明; 张爱滨; 范德江; 邓声贵; 王亮; 张喜林; 赵全民

    2012-01-01

    对渤海中部底质沉积物中的重金属元素Cu、Pb、Zn、Cr、V、Ni的含量和空间分布进行了分析,与国内外其他海域进行了对比,探讨了重金属来源,并对沉积物中重金属进行了环境质量评价.研究发现,该区重金属元素Cu、Pb、Zn、Cr、V、Ni的平均含量分别为22.50,24.26,64.27,59.66,67.91,30.57μg/g,重金属在海河口附近、渤海湾中部、渤海中部泥质区及辽东半岛沿岸的含量较高,而在研究区东部的渤中浅滩和渤海湾北部的含量较低.与国内外其他海域相比,研究区的重金属含量处于中等水平.重金属以自然来源为主,同时受到人类活动的显著影响.采用地质累积指数法和生态危害评价法对研究区底质沉积物的环境质量评价表明:渤海湾北部和研究区东部的渤中浅滩污染程度较轻或者无污染;辽东半岛沿岸为轻度污染;海河口及天津沿岸、渤海湾中部、研究区中部泥质区为中度污染.污染元素主要是Pb,其次为Cr、Zn和V而Cu和Ni的污染程度较低.%The distributions and environmental quality assessments of heavy metals Cu, Pb, Zn; Cr, V, Ni in the surface sediments in the central region of the Bohai Sea were performed. The contents of heavy metals Cu, Pb, Zn, Cr, V, Ni were 22.50, 24.26, 64.27, 59.66, 67.91 and 30.57ng/g, respectively. The contents were high in the Haihe River mouth and central region of the Bohai Bay, the mud area in the central study region and the coastal area of south Liaodong Peninsula; while that were low in the east of study area and the northern Bohai Bay. They were in middle level compared with that in other domestic and foreign regions. The heavy metals mainly came from natural sources, but were affected significantly by human activities. The environment quality evaluation of the sediment was carried out by the methods of geological cumulative index and ecological risk assessment. There were light polluted or non-pollution in the

  2. Historic changes in flux of matter and nutrient budgets in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    LIU Sumei; ZHANG Jing; GAO Huiwang; LIU Zhe

    2008-01-01

    Over the past four periods ( 1959-1960, 1982-1983, 1992-1993, and 1998-1999), the ecosystem of the Bohai Sea changed due to both a significant decrease of river water discharge from the Huanghe River and a reduction of precipitation. The shifts in nutrient chemistry could result in changes in the phytoplankton composition with an increased potential for non-diatom algal blooms. Simple box model was used to estimate the water - mass balance and nutrient budgets for the Bohai Sea. Water budgets indicate that the residual flow changed from out of the Bohai Sea before 1993, but became inflow to the Bohai Sea after then. The nutrient budgets developed indicate that the Bohai Sea was a sink for nutrients except for phosphate in 1959-1960 and 1982-1983 and for silicate in 1982-1983. Net water flow transports nutrients out of the Bohai Sea in 1959-1960, 1982-1983 and 1992-1993, but into the sea in 1998-1999 due to climate changes, such as precipitation and subsequent freshwater discharge.The residual fluxes of nutrients are minor relative to atmospheric deposition and riverine inputs. Conversions of phosphate values to carbon by stoichiometric ratios were used to predict that the system was net heterotrophic before 1982-1983 and net autotrophic after then. Nutrient budgets can explain the change of nutrient concentrations in the Bohai Sea except nitrates, which should include the surface runoff.

  3. Control of facies/potential on hydrocarbon accumulation:a geological model for Iacustrine rift basins

    Institute of Scientific and Technical Information of China (English)

    Chen Dongxia; Pang Xiongqi; Zhang Shanwen; Wang Yongshi; Zhang Jun

    2008-01-01

    The formation and distribution of hydrocarbon accumulations are jointly controlled by"stratigraphic facies"and"fluid potential",which can be abbreviated in"control of facies/potential on hydrocarbon accumulation".Facies and potential control the time-space distribution of hydrocarbon accumulation macroscopically and the petroliferous characteristics of hydrocarbon accumulation microscopically.Tectonic facies and sedimentary facies control the time-space distribution.Lithofacies and petrophysical facies control the petroliferous characteristics.Favorable facies and high porosity and permeability control hydrocarbon accumulation in the lacustrine rift basins in China.Fluid potential is represented by the work required,which comprises the work against gravity,pressure,interfacial energy and kinetic energy.Hydrocarbon migration and accumulation are controlled by the joint action of multiple driving forces,and are characterized by accumulation in the area of low potential.At the structural high,low geopotential energy caused by buoyancy control anticlinal reservoir.The formation of lithological oil pool is controlled by low interfacial energy caused by capillary force.Low compressive energy caused by overpressure and faulting activity control the formation of the faulted block reservoir.Low geopotential energy of the basin margin caused by buoyancy control stratigraphic reservoir.The statistics of a large number of oil reservoirs show that favorable facies and low potential control hydrocarbon accumulation in the rift basin.where over 85% of the discovered hydrocarbon accumulations are distributed in the trap with favorable facies and lOW potentials.The case study showed that the prediction of favorable areas by application of the near source-favorable facies-low potential accumulation model correlated well with over 90% of the discovered oil pools' distribution of the middle section of the third member of the Shahejie Formation in the Dongying Depression,Bohai Bay

  4. Controls on alkylphenol occurrence and distribution in oils from lacustrine rift basins in East China

    Institute of Scientific and Technical Information of China (English)

    ZHOU ShuQing; HUANG HaiPing

    2008-01-01

    Oils from two lacustrine rift basins in east China are thoroughly investigated using geochemical method to understand controls on alkylphenol occurrence and distribution in oils. Oils in the Lujiapu Depression,Kailu Basin are derived from the Cretaceous source rocks,and those in the Dongying Depression,Bohai Bay Basin,from the Tertiary source rocks. All oils are experienced relatively short distance of migration and have similar maturity in each basin. Differences in homologue distributions from different oilfields are most likely caused by organic facies variation of source rocks. The oils in the Lujiapu Depression are characterized by high proportion of C3 alkylphenols (prefixes refer to the number of alkylcarbons joined to the aromatic ring of the phenol molecule) and low proportion of cresols and C2 alkylphenols compared to oils from the Dongying Depression. Alkylphenol isomer distribution is possibly affected by depositional environment especially for C3 alkylphenols. Dysoxic freshwater environment is favorable for the formation of propyl or isopropyl substituted C3 alkylphenols,while highly reducing saline water is more suitable for trimethyl substituted C3 alkylphenols. Variations in alkylphenol concentrations within a petroleum system are controlled mainly by secondary migration processes with alkylphenol concentrations decreasing along migration direction. Interestingly,coupled with geological factors,a subtle change of alkylphenol concentrations can be applied to differentiate carrier systems. When oil migrates through sandy beds,concentrations of total alkylphenols decrease dramatically with migration distance,while such change is less significant when oil migrates vertically along faults. However,most isomer ratios potentially related to migration distance are not as effective as those alkylcarbazoles in migration diagnosis due to complicated affecting factors.

  5. Seabed morphology and gas venting features in the continental slope region of KrishnaeGodavari basin, Bay of Bengal: Implications in gas–hydrate exploration

    Digital Repository Service at National Institute of Oceanography (India)

    Dewangan, P.; Ramprasad, T.; Ramana, M.V.; Mazumdar, A.; Desa, M.; Badesab, F.K.

    Increased oil and gas exploration activity has led to a detailed investigation of the continental shelf and adjacent slope regions of Mahanadi, KrishnaeGodavari (KG) and Cauvery basins, which are promising petroliferous basins along the eastern...

  6. Geoid and gravity anomaly data of conjugate regions of Bay of Bengal and Enderby Basin: New constraints on breakup and early spreading history between India and Antarctica

    Digital Repository Service at National Institute of Oceanography (India)

    Krishna, K.S.; Michael, L.; Bhattacharyya, R.; Majumdar, T.J.

    , along latitudes 13ºN (MAN-03), 14ºN (SK107-7), 14.64ºN (MAN-01) and 15.5ºN (SK 107-6). In addition we have also extracted gravity and magnetic profiles of the Bay of Bengal from NGDC database and used for integrated investigations. Gravity... and magnetic anomaly data of the Bay of Bengal are plotted at right angle to the profiles and shown in Figures 6 and 7, respectively. Gravity anomaly data along the profile MAN-01 (Bay of Bengal) are segmented into intermediate (100-200 km) and long...

  7. NUMERICAL SIMULATION OF 1998 RED TIDE OF THE BOHAI SEA

    Institute of Scientific and Technical Information of China (English)

    Yongsheng WU; Zhao-Yin WANG

    2002-01-01

    Algal bloom,known as red tide,has occurred frequently in the Bohai Sea in recent decades causing great economic losses to fisheries as well as having significant adverse impact on the environment. A 3-D Eco-Hydraulic model is developed to simulate the explosive propagation of diatom and dinoflagellate as a function of the concentration of various nutrients,river inflow,tide,temperature,wind,sunshine and rainfall. The model is intended to answer the questions ofhow the 1998 Bohai Sea red tide occurred,and to investigate how environmental factors,such as temperature,wind,rainfall,solar radiance,sea currents and nutrients,affect the algal bloom process. The parameters employed in the model are calibrated with the data collected in the periods 1982-1983 and 1992-1993. Results from the model indicate that eutrophication of the seawater is the basic condition for algal bloom,and that the 1998 red tide was triggered by the abnormal warm weather in August and September.

  8. Petroleum hydrocarbons and their effects on fishery species in the Bohai Sea,North China

    Institute of Scientific and Technical Information of China (English)

    Sisi Xu; Jinming Song; Huamao Yuan; Xuegang Li; Ning Li; Liqin Duan; Yu Yu

    2011-01-01

    Systematic studies on the changes in concentrations of petroleum hydrocarbons (PHs) and their effects on fishery species in the Bohai Sea during 1974-2004 are presented. Changes in PHs concentrations were closely related to Yellow River runoff. Concentrations of PHs accumulated in fish and shrimp increased by about 0.712 mg/kg dry weight when trophic level of fish and shrimps increased by 1. Attention should also be paid to the high PHs concentrations in mollusks along the coastal waters of the Bohai Sea. Average concentration of PHs in the adjacent coastal waters of Tianjin City during 1996-2005 decreased the population growth rates of fish,crustaceans and mollusks in the Bohai Sea by 2.58%, 6.59% and 2.33%, respectively. Therefore, PHs have significantly contributed to the decline in fisheries in the Bohai Sea, and they must be reduced to realize the sustainable fisheries.

  9. Analysis of Interannual Variations of Inorganic Nitrogen in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    Shi Qiang; Gao Zhenhui; Yang Jianqiang

    2002-01-01

    According to the Bohai Sea cross-section data during 1985~1998, the high concentration inorganic nitrogen in the Bohai Sea section bottom layer water nearshore diffused and transferred to the middle of the Bohai Sea year after year. The interannual variations of the concentration of inorganic nitrogen in the Bohai Sea section bottom layer water may reflect the degree of eutrophication more steadily. The nitrate nitrogen and nitrite nitrogen are used to show quasi-equilibrium state interannual variations, but with the aggravation of seawater pollution, the quasi-equilibrium state of interannual variations has been broken and the marine biological-chemical processes can only maintain the secondary part of the interannual variations in a quasi-equilibrium state, but are not sufficient to prevent the main pan of interannual variations from deviating from the quasi-equilibrium state. The spatial distributions of inorganic nitrogen would be affected by the reproduction and swarming of marine life.

  10. Preliminary assessment of channel stability and bed-material transport in the Tillamook Bay tributaries and Nehalem River basin, northwestern Oregon

    Science.gov (United States)

    Jones, Krista L.; Keith, Mackenzie K.; O'Connor, Jim E.; Mangano, Joseph F.; Wallick, J. Rose

    2012-01-01

    valley confinement. * Natural and human-caused disturbances such as mass movements, logging, fire, channel modifications for navigation and flood control, and gravel mining also have varying effects on channel condition, bed-material transport, and distribution and area of bars throughout the study areas and over time. * Existing datasets include at least 16 and 18 sets of aerial and orthophotographs that were taken of the study areas in the Tillamook Bay tributary basins and Nehalem River basin, respectively, from 1939 to 2011. These photographs are available for future assessments of long-term changes in channel condition, bar area, and vegetation establishment patterns. High resolution Light Detection And Ranging (LiDAR) surveys acquired in 2007-2009 could support future quantitative analyses of channel morphology and bed-material transport in all study areas. * A review of deposited and mined gravel volumes reported for instream gravel mining sites shows that bed-material deposition tends to rebuild mined bar surfaces in most years. Mean annual deposition volumes on individual bars exceeded 3,000 cubic meters (m3) on Donaldson Bar on the Wilson River, Dill Bar on the Kilchis River, and Plant and Winslow Bars on the Nehalem River. Cumulative reported volumes of bed-material deposition were greatest at Donaldson and Dill Bars, totaling over 25,000 m3 per site from 2004 to 2011. Within this period, reported cumulative mined volumes were greatest for the Donaldson, Plant, and Winslow Bars, ranging from 24,470 to 33,940 m3. * Analysis of historical stage-streamflow data collected by the U.S. Geological Survey on the Wilson River near Tillamook (14301500) and Nehalem River near Foss (14301000) shows that these rivers have episodically aggraded and incised, mostly following high flow events, but they do not exhibit systematic, long-term trends in bed elevation. * Multiple cross sections show that channels near bridge crossings in all six study areas are dynamic with many

  11. Elevated nitrogen-containing particles observed in Asian dust aerosol samples collected at the marine boundary layer of the Bohai Sea and the Yellow Sea

    Directory of Open Access Journals (Sweden)

    H. Geng

    2009-06-01

    Full Text Available Low-Z particle electron probe X-ray microanalysis (low-Z particle EPMA shows powerful advantages for the characterization of ambient particulate matter in environmental and geological applications. By the application of the low-Z particle EPMA single particle analysis, an overall examination of 1800 coarse and fine particles (aerodynamic diameters: 2.5–10 μm and 1.0–2.5 μm, respectively in six samples collected on 28 April–1 May 2006 in the marine boundary layer (MBL of the Bohai Sea and Yellow Sea was conducted. Three samples (D1, D2, and D3 were collected along the Bohai Bay, Bohai Straits, and Yellow Sea near Korea during an Asian dust storm event while the other three samples (N3, N2, and N1 were collected on normal days. Based on X-ray spectral and secondary electron image data, 15 different types of particles were identified, in which soil-derived particles were encountered with the largest frequency, followed by (C, N, O-rich droplets (likely the mixture of organic matter and NH4NO3, particles of marine origin, and carbonaceous, Fe-rich, fly ash, and (C, N, O, S-rich droplet particles. Results show that during the Asian dust storm event relative abundances of the (C, N, O-rich droplets and the nitrate-containing secondary soil-derived particles were markedly increased (on average by a factor of 4.5 and 2, respectively in coarse fraction and by a factor of 1.9 and 1.5, respectively in fine fraction in the MBL of the Bohai Sea and Yellow Sea, implying that Asian dust aerosols in springtime are an important carrier of gaseous inorganic nitrogen species, especially NOx (or HNO3 and NH3.

  12. Preliminary study on seasonal succession and development pathway of phytoplankton community in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Phytoplankton species composition and species succession were determined in 1998~1999 based on 2 nestle investigation cruises in the Bohai Sea and two monthly monitoring stations at Penglai and Changdao for 15 months. The seasonal succession and pathway of phytoplankton community in the Bohai Sea were discussed complementarily with history data. The main process of phytoplankton community development in the Bohai Sea was controlled by temperature and nutrient replenishes. There were two cell abundance peaks in an annual variation, the main peak in April and the secondary peak in September. In winter, the cell abundance was low due to the low temperature, the phytoplankton community was mainly made up of small-crled diatoms. In spring, the phytoplankton community was developed very quickly by small-celled diatom in suitable conditions of temperature and nutrients. In summer, the cell abundance decreased and big-celled diatoms became predominated. In autumn, because of the replenish of nutrient, big-celled diatoms and dinoflagellates formed another cell abundance peak.During the annual variation of phytoplankton community in the Bohai Sea, species succession was the main process of community development, the species sequence just occur at special areas and special periods. The evolution of phytoplankton community in the Bohai Sea accords with the hypothesis of Margalef's phytoplankton community of four stages. But the size feature is contrary to the hypothesis,which may be caused by nutrient replenish in autumn in Bohai Sea and the top to down control.

  13. Beach morphology and coastline evolution in the southern Bohai Strait

    Science.gov (United States)

    Zhang, Wei; Wu, Jianzheng; Li, Weiran; Zhu, Longhai; Hu, Rijun; Jiang, shenghui; Sun, Yonggen; Wang, Huijuan

    2015-10-01

    The beach studied in this paper spans a length of 51 km and is one of several long sandy beaches in the southern Bohai Strait. Due to the obstruction of islands in the northeast and the influence of the underwater topography, the wave environment in the offshore area is complex; beach types and sediment transport characteristics vary along different coasts. The coastlines extracted from six aerial photographs in different years were compared to demonstrate the evolving features. Seven typical beach profiles were selected to study the lateral beach variation characteristics. Continuous wind and wave observation data from Beihuangcheng ocean station during 2009 were employed for the hindcast of the local wave environment using a regional spectral wave model. Then the results of the wave hindcast were incorporated into the LITDRIFT model to compute the sediment transport rates and directions along the coasts and analyze the longshore sand movement. The results show that the coastline evolution of sand beaches in the southern Bohai Strait has spatial and temporal variations and the coast can be divided into four typical regions. Region (I), the north coast of Qimudao, is a slightly eroded and dissipative beach with a large sediment transport rate; Region (II), the southwest coast of Gangluan Port, is a slightly deposited and dissipative beach with moderate sediment transport rate; Region (III), in the central area, is a beach that is gradually transformed from a slightly eroded dissipative beach to a moderately or slightly strong eroded bar-trough beach from west to east with a relatively moderate sediment transport rate. Region (IV), on the east coast, is a strongly eroded and reflective beach with a weak sediment transport rate. The wave conditions exhibit an increasing trend from west to east in the offshore area. The distribution of the wave-induced current inside the wave breaking region and the littoral sediment transport in the nearshore region exhibit a gradual

  14. Species and distribution of inorganic selenium in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    For studying geochemical behavior of selenium, a marine investigation was conducted in September 1998 cruise in the Bohai Sea. Horizontal and vertical distributions of inorganic selenium and selenite were studied. The inorganic selenium varied from 0.73 to 2.41 nmol/L, with an average of 1.31 nmol/L; while selenite varied from 0.18 to 0.72 nmol/L with an average of 0.47 nmol/L. The average ratio of selenite to selenate was 0.68, and selenate was the predominant species of inorganic selenium in the most study area. Concentrations of inorganic selenium and selenite decreased with distance from the coast. No apparent variations of the concentration between surface and bottom was shown. There were two water masses in the area, one from the Huanghe (Yellow) River and other from the Yellow Sea. Of the two,Huanghe River was the major source of inorganic selenium.

  15. Manganese Abnormity in Holocene Sediments of the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Manganese abnormity has been observed in the Holocene sediments of the mud area of Bohai Sea. On the basis of grain size, chemical composition, heavy mineral content and accelerator mass spectrometry (AMS) 14C dating of foraminifer, relationships between manganese abnormity and sedimentation rates, material source, hydrodynamic conditions are probed. Manganese abnormity occurred during the Middle Holocene when sea level and sedimentation rates were higher than those at present. Sedimentary hiatus was not observed when material sources and hydrodynamic conditions were quite similar. Compared with the former period, the latter period showed a decrease in reduction environment and an inclination toward oxidation environment with high manganese content, whereas provenance and hydrodynamic conditions showed only a slight change. From the above observations, it can be concluded that correlation among manganese abnormity, material source, and hydrodynamic conditions is not obvious. Redox environment seems to be the key factor for manganese enrichment, which is mainly related to marine authigenic process.

  16. Annual Cycle and Budgets of Nutrients in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    ZHAO Liang; WEI Hao; FENG Shizuo

    2002-01-01

    The environmental problems in the Bohai Sea have become more serious in the last decade. High nutrient concentration contributes much to it. A Sino-German cooperation program has been carried out to improve the understanding of the ecosystem by observations and modelling. A three-dimensional ecosystem model, coupled with a physical transport model, is adopted in this study. The simulation for the year 1982 is validated by the data collected in 1982/1983. The simulated annual mean nutrient concentrations are in good agreement with observations. The nutrient concentrations in the Bohai Sea, which are crucial to the algal growth, are high in winter and low in summer. There are depletion from spring to summer and elevation from autumn to winter for nutrients. The nutrients' depletion is a response to the consumption of the phytoplankton bloom in spring. Internal recycle and external compensation affect the nutrient cycle. Their contributions to the nutrient budgets are discussed based on the simulated results. Production and respiration are the most important sink and source of nutrients. The process of photosynthesis consumes 152 kilotons-P and 831.1 kilotons-N while respiration releases 94.5 kilotons-P and 516.6 kilotons-N in the same period. The remineralization of the detritus pool is an important source of nutrient regeneration. It can compensate 23 percent of the nutrient consumed by the production process. The inputs of phosphates and nitrogen from rivers are 0.55 and 52.7 kilotons respectively. The net nutrient budget is - 3.05 kilotons-P and 31.6 kilotons-N.

  17. Formation mechanism and model for sand lens reservoirs in the Jiyang Sub-basin, East China

    Institute of Scientific and Technical Information of China (English)

    LI; Pilong; PANG; Xiongqi; CHEN; Dongxia; ZHANG; Shanwen

    2004-01-01

    The Bohai Bay basin comprises some very important and well documented subtle traps known in China, which have been the major exploration focus and have become a major petroleum play since the 1990s. However, recent exploration showed that the oil-bearing properties of some sand lens reservoirs may vary significantly and the accumulation mechanisms for these lithological subtle traps are not well understood. Based on statistical analysis of oil-bearing properties for 123 sand lens reservoirs in the Jiyang Sub-basin and combined with detailed anatomy of typical sand lens reservoirs and NMR experiments, it has been shown that the structural and sedimentary factors, hydrocarbon generation and expulsion conditions of the surrounding source rocks, as well as the petrophysical properties of sand lens reservoirs are the main controlling factors for the formation of sand lens reservoirs. The formation of a sand lens reservoir depends on the interaction between the hydrocarbon accumulation driving force and the resistance force. The driving force is made up of the differential capillary pressure between sandstones and sources rocks and the hydrocarbon diffusion force, and as well as the hydrocarbon expansion force. The resistance force is the friction resistance force for hydrocarbons and water to move through the pore throats of the sand lens. The sedimentary environment, source rock condition and sand reservoir properties can change from unfavorable to favorable depending on the combination of these factors. When these three factors all reach certain thresholds, the sand lens reservoirs may begin to be filled by hydrocarbons. When all of these conditions become favorable for the formation of sand lens reservoirs, the reservoir would have high oil saturation. This approach has been applied to evaluating the potential of petroleum accumulation in the sand lens reservoirs in the third member of the Neogene Shahejie Formation in the Jiyang Sub-basin.

  18. Complex petroleum accumulating process and accumulation series in the buried-hill trend in the rift basin:An example of Xinglongtai structure trend,Liaohe subbasin

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The buried-hill trend is a typical style of the petroliferous structure in the faulted basin of eastern China. The Xinglongtai structure trend in the Liaohe subbasin,Bohai Bay Basin is a buried faulted-hill trend resulting from the periodic faulting of the Tai’an-Dawa faults. The structure was cut by various faults,which are interlinked and constitute the conduits for petroleum migration. Petroleum accumulated in the Tertiary sandstones and pre-Tertiary basement of metamorphosed rocks through the migration pathways of the fault system. Petroleum in the structure was derived from different hydrocarbon kitchens to form a hybrid field complex. Petroleum charged the structure from different directions and accumulated in various reservoirs through different pathways in different times. The accumulations in the buried hill trend of Xingongtai are composed of two types of traps in the two stratigraphic systems: traps in the Tertiary sandstones were formed by the fault blocks and by the pinchout of the sandstone,and traps in the pre-Tertiary basement of metamorphosed rocks were formed by fissures in the inner part of the buried hills and by the unconformity near the surface of the buried hills.

  19. A method for examining the geospatial distribution of CO2 storage resources applied to the Pre-Punta Gorda Composite and Dollar Bay reservoirs of the South Florida Basin, U.S.A

    Science.gov (United States)

    Roberts-Ashby, Tina; Brandon N. Ashby,

    2016-01-01

    This paper demonstrates geospatial modification of the USGS methodology for assessing geologic CO2 storage resources, and was applied to the Pre-Punta Gorda Composite and Dollar Bay reservoirs of the South Florida Basin. The study provides detailed evaluation of porous intervals within these reservoirs and utilizes GIS to evaluate the potential spatial distribution of reservoir parameters and volume of CO2 that can be stored. This study also shows that incorporating spatial variation of parameters using detailed and robust datasets may improve estimates of storage resources when compared to applying uniform values across the study area derived from small datasets, like many assessment methodologies. Geospatially derived estimates of storage resources presented here (Pre-Punta Gorda Composite = 105,570 MtCO2; Dollar Bay = 24,760 MtCO2) were greater than previous assessments, which was largely attributed to the fact that detailed evaluation of these reservoirs resulted in higher estimates of porosity and net-porous thickness, and areas of high porosity and thick net-porous intervals were incorporated into the model, likely increasing the calculated volume of storage space available for CO2 sequestration. The geospatial method for evaluating CO2 storage resources also provides the ability to identify areas that potentially contain higher volumes of storage resources, as well as areas that might be less favorable.

  20. Distribution and behavior of major and trace elements in Tokyo Bay, Mutsu Bay and Funka Bay marine sediments

    Energy Technology Data Exchange (ETDEWEB)

    Honda, Teruyuki [Musashi Inst. of Technology, Atomic Energy Research Laboratory, Kawasaki, Kanagawa (Japan); Kimura, Ken-ichiro [Musashi Inst. of Technology, Graduate School, Research Division in Engineering, Kawasaki, Kanagawa (Japan)

    2003-06-01

    Fourteen major and trace elements in marine sediment core samples collected from the coasts along eastern Japan, i.e. Tokyo Bay (II) (the recess), Tokyo Bay (IV) (the mouth), Mutsu Bay and Funka Bay and the Northwest Pacific basin as a comparative subject were determined by the instrumental neutron activation analysis (INAA). The sedimentation rates and sedimentary ages were calculated for the coastal sediment cores by the {sup 210}Pb method. The results obtained in this study are summarized as follows: (1) Lanthanoid abundance patterns suggested that the major origin of the sediments was terrigenous material. La*/Lu* and Ce*/La* ratios revealed that the sediments from Tokyo Bay (II) and Mutsu Bay more directly reflected the contribution from river than those of other regions. In addition, the Th/Sc ratio indicated that the coastal sediments mainly originated in the materials from the volcanic island-arcs, Japanese islands, whereas those from the Northwest Pacific mainly from the continent. (2) The correlation between the Ce/U and Th/U ratios with high correlation coefficients of 0.920 to 0.991 indicated that all the sediments from Tokyo Bay (II) and Funka Bay were in reducing conditions while at least the upper sediments from Tokyo Bay (IV) and Mutsu Bay were in oxidizing conditions. (3) It became quite obvious that the sedimentation mechanism and the sedimentation environment at Tokyo Bay (II) was different from those at Tokyo Bay (IV), since the sedimentation rate at Tokyo Bay (II) was approximately twice as large as that at Tokyo Bay (IV). The sedimentary age of the 5th layer (8{approx}10 cm in depth) from Funka Bay was calculated at approximately 1940{approx}50, which agreed with the time, 1943{approx}45 when Showa-shinzan was formed by the eruption of the Usu volcano. (author)

  1. Genetic classification of natural gases in the Bozhong Depression, Bohai Bay, China

    Institute of Scientific and Technical Information of China (English)

    TANG Youjun; WEN Zhigang

    2007-01-01

    The geochemical characteristics of natural gases discovered in the Bozhong Depression are systematically described in this paper. The natural gases are composed mainly of hydrocarbon gases. Natural gases occurring in the Paleogene and older reservoirs are wet gases, whereas those in the Neogene reservoirs are dry gases. Methane and ethane in the gases are significantly different in carbon isotopic composition. The methane carbon isotopic composition of the gases in structure BZ28-1 and the ethane carbon isotopic composition of the gases in structure QHD30-1 are characterized by the heaviest values, respectively. The natural gases are in the mature to highly mature stages. The hydrocarbon gases are of organic origin and can be classified as oil-type gases, coal-derived gases and mixed gases with the third one accounting for the major portion.

  2. Vibration Sensor Approaches for the Monitoring of Sand Production in Bohai Bay

    OpenAIRE

    Kai Wang; Zhiguo Liu; Gang Liu; Longtao Yi; Kui Yang; Shiqi Peng; Man Chen

    2015-01-01

    The real-time monitoring of sand production has always been an important issue during the process of oil production in offshore field. This paper illustrates a new alternative vibration sensor approach to monitor the sand production. A special broadband sensor was selected. Then the time-frequency analysis, characteristic sand frequency band filter method, and peak searching-denoising method were proposed to enhance the detection ability of sand vibration signals in strong background noises o...

  3. Biogenic silicate accumulation in sediments, Jiaozhou Bay

    Institute of Scientific and Technical Information of China (English)

    LI Xuegang; SONG Jinming; DAI Jicui; YUAN Huamao; LI Ning; LI Fengye; SUN Song

    2006-01-01

    It has been widely recognized that low silicate content in seawater is a major limiting factor to phytoplankton primary production in Jiaozhou Bay. However the reason of Si-limitation remains poorly understood. In the present study we measured the biogenic silicate content and discussed the accumulation of silicate in Jiaozhou Bay sediment. The results show that the biogenic silica content in the sediment of the Jiaozhou Bay is obviously much higher than those in the Yellow Sea and the Bohai Sea. The BSi:TN ratios and BSi:16P ratios in the sediment are > 1 and the OC:BSi ratio in sediment is lower than these of Redfield ratio (106:16), indicating that the decomposition rate of OC is much higher than that for BSi in similar conditions. Therefore, the majority of the biogenic silicate was buried and thus did not participate in silicate recycling. Silicate accumulation in sediment may explain why Si limits the phytoplankton growth in the Jiaozhou Bay. Comparing the flux of biogenic silicate from sediments with primary production rate, it can be concluded that only 15.5% of biogenic silicate is hydrolyzed during the journey from surface to bottom in seawater, thus approximate 84.5% of biogenic silicate could reach the bottom. The silicate releasing rate from the sediment to seawater is considerably lower than that of sedimentation of biogenic silicate, indicating silicate accumulation in sediment too. In a word, the silicate accumulation in sediment is the key reason of silicate limiting to phytoplankton growth in Jiaozhou Bay.

  4. A coupled ice-ocean model for the Bohai Sea Ⅱ. Case study

    Institute of Scientific and Technical Information of China (English)

    SU Jie; WU Huiding; ZHANG Yunfei; LIU Qinzhen; BAI Shan

    2005-01-01

    The coupled ice-ocean model for the Bohai Sea is used for simulating the freezing, melting, and variation of ice cover and the heat balance at the sea-ice, air-ice, and air-sea interfaces of the Bohai Sea during the entire winter in 1998~1999 and 2000~2001. The coupled model is forced by real time numerical weather prediction fields. The results show that the thermodynamic effects of atmosphere and ocean are very important for the evolvement of ice in the Bohai Sea, especially in the period of ice freezing and melting. Ocean heat flux plays a key role in the thermodynamic coupling. The simulation also presents the different thermodynamic features in the ice covered region and the marginal ice zone. Ice thickness, heat budget at the interface, and surface sea temperature, etc. between the two representative points are discussed.

  5. SHORT TIME DYNAMICS OF CILIATE ABUNDANCE IN THE BOHAI SEA (CHINA)

    Institute of Scientific and Technical Information of China (English)

    张武昌; 王荣

    2002-01-01

    The ciliate community in the Bohai Sea (China) was studied from23 September to 7 October 1998. A hurricane struck the study area between the two grid station investigations, which were six days apart. Six tintinnid species(Favella panamensis, Leptotintinnus nordqvisti, Tintinnopsis butschlii, T. karajacensis, T. Radix and Wangiella dicollaria) were identified. Total cililate abundance in the surface layer ranged from 20 to 770 ind/l. In the first grid investigation, Tintinnopsis karajacensis dominated in the warm, low salinity waters at the Huanghe River mouth. Aloricate ciliate sp.1 dominated in the cold, high salinity waters in the northwest of the study area and the Bohai Strait. In the second grid investigation, T. Karajacensis almost disappeared. The abundance of aloricate ciliate sp.1 decreased drastically. The aloricate ciliate sp.2 dominatedat the Bohai Strait. The change of ciliate abundance may be due to the disturbance of hurricane.``

  6. Fabric and crystal characteristics of Bohai and Arctic sea ice

    Institute of Scientific and Technical Information of China (English)

    李志军; 康建成; 蒲毅彬

    2002-01-01

    The fabrics and crystals of Bohai one-year ice show that the noncontinuous ice growth rate enables the level ice layers with different amount of air bubbles to be formed in lower part of an ice sheet which was clearly seen from CT technology; typical grain ice and columnar ice occur in the grey ice which grows in stable water; thaw-refrozen ice and rafted ice have their specific crystal characters. On the Arctic sea ice, the ice core located at 72°24.037′N, 153°33.994′W and 2.2 m in length was a 3-year ice floe and a new sort of crystal was found, which is defined as refrozen clastic pieces. The crystal profile of the ice core 4.86 m in length located at 74°58.614′N, 160°31.830′W shows the evidence that ice ridge changed into hummock.

  7. Distribution of biomass of heterotrophic bacterioplankton in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Distribution, variation and impact factors of biomass of bacterioplankton from April to May 1999in Bohai Sea were studied in DAPI method with epifluorescence microscopy. The biomass in surface waters showed a small day-night variation, varying from 0.13 to 2.51 μg/dm3 with an average of 0.84 μg/dm3. The biomass in bottom waters showed, however, a large variation, changing from 0.15 to 4.18 μg/dm3 with an average of 1.36 μg/dm3. The peak values occurred at 5 and 11 a.m. The bottom water biomass showed a significant correlation with particulate organic carbon (r=0.639, P<0.05). Heterotrophic bacterioplankton biomass was high in nearshore waters and low in offshore areas with a high biomass zone around Huanghe (Yellow) River mouth,showing the same distribution of nutrients. In vertical distribution, heterotrophic bacteria biomass in bottom waters was higher than that in surface water.

  8. Satellite observations of oil spills in Bohai Sea

    International Nuclear Information System (INIS)

    Several oil spills occurred at two oil platforms in Bohai Sea, China on June 4 and 17, 2011. The oil spills were subsequently imaged by different types of satellite sensors including SAR (Synthetic Aperture Radar), Chinese HJ-1-B CCD and NOAA MODIS. In order to detect the oil spills more accurately, images of the former three sensors were used in this study. Oil spills were detected using the semi-supervised Texture-Classifying Neural Network Algorithm (TCNNA) in SAR images and gradient edge detection algorithm in HJ-1-B and MODIS images. The results show that, on June 11, the area of oil slicks is 31 km2 and they are observed in the vicinity and to the north of the oilfield in SAR image. The coverage of the oil spill expands dramatically to 244 km2 due to the newly released oil after June 11 in SAR image of June 14. The results on June 19 show that under a cloud-free condition, CCD and MODIS images capture the oil spills clearly while TCNNA cannot separate them from the background surface, which implies that the optical images play an important role in oil detection besides SAR images

  9. Model study on Bohai ecosystem 1. Model description and primary productivity

    Institute of Scientific and Technical Information of China (English)

    LIU Hao; YIN Baoshu

    2006-01-01

    A Nutrient-Phytoplankton-Zooplankton(NPZD) type of ecological model is developed to reflect the biochemical process, and further coupled to a primitive equation ocean model, an irradiation model as well as a river discharge model to reproduce ecosystem dynamics in the Bohai Sea. Modeled primary production shows reasonable consistency with observations quantitatively and qualitatively; in addition, f-ratio is examined in detail in the first time, which is also within the range reported in other studies and reveals some meaningful insight into the relative contributions of ammonium and nitrate to the growth of phytoplankton in the Bohai Sea.

  10. Introducing Seawater China for Sustainablefrom Bohai Sea to WestDevelopment in the Area

    Institute of Scientific and Technical Information of China (English)

    ChenChangli

    2004-01-01

    Sustained and profound aridization process in north-west China in Tertiary and Quaternary period and time of mankind history are discussed. The rain-creased function of 3 set high mountain condensation systems in north-west China is recognized once more. A sandstorm happened on 20th March 2002 in Alasan and Ejinaqi areas was very strong and arrived in Japan and Korea. For saving Alasan area from sandstorm a way of introducing sea water from Bohai to Alasan has been proposed. Four problems are replied in this paper. It is concluded that introducing sea water from Bohai to west China is the best way for sustainable development of west China.

  11. Hydrocarbon accumulation in network and its application in the continental rift basin

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Bohai Bay Basin as an application example.

  12. Assessing the effectiveness of winter cover crop on nitrate reduction in two-paired sub-basins on the Coastal Plain of the Chesapeake Bay Watershed

    Science.gov (United States)

    Lee, S.; Yeo, I. Y.; Sadeghi, A. M.; Mccarty, G.; Hively, W. D.; Lang, M. W.

    2014-12-01

    Best management practices (BMPs) have been widely adopted to improve water quality throughout the Chesapeake Bay Watershed (CBW). Winter cover crops (WCC) use has been highlighted for the reduction of nitrate leaching over the fallow season. Although various WCC practices are currently conducted in local croplands, the water quality improvement benefits of WCC have not been studied thoroughly at the watershed scale. The objective of this study is to assess the long-term impacts of WCC on reducing nitrate loadings using a processed-based watershed model, Soil and Water Assessment Tool (SWAT). Remote sensing based estimates of WCC biomass will be used to calibrate plant growth processes of SWAT and its nutrient cycling. The study will be undertaken in two-paired agricultural watersheds in the Coastal Plain of CBW. Multiple WCC practice scenarios will be prepared to investigate how nitrate loading varies with crop species, planting dates, and implementation areas. The performance of WCC on two-paired watersheds will be compared in order to understand the effects of different watershed characteristics on nitrate uptake by crops. The results will demonstrate the nitrate reduction efficiency of different WCC practices and identify the targeting area for WCC implementation at the watershed scale. This study will not only integrate remote sensing data into the physically based model but also extend our understandings of WCC functions. This will provide key information for effective conservation decision making. Key words: Water quality, Chesapeake Bay Watershed, Winter Cover Crop, Soil and Water Assessment Tool (SWAT)

  13. Pore-water chemistry of sediment cores off Mahanadi Basin, Bay of Bengal: Possible link to deep seated methane hydrate deposit

    Digital Repository Service at National Institute of Oceanography (India)

    Mazumdar, A.; Peketi, A.; Joao, H.M.; Dewangan, P.; Ramprasad, T.

    electrons via enzymatic pathways (Canfield, 2001). Sulfate reducing bacteria are most active close to the sediment water interface owing to high labile organic load and sulfate flux at the interface (Kasten and Jørgensen, 2000; Megonigal et al., 2003, Wall... from 70 to 80 ‰ VPDP indicate the microbial origin of methane in Mahanadi basin via CO2 reduction pathway. Other factors which may influence δ13CCH4 include methanogenic precursor, fractionation factor and temperature etc. (Alperin et al., 1992...

  14. Identification and quantification of shipping emissions in Bohai Rim, China

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Fan [Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Chen, Yingjun, E-mail: yjchen@yic.ac.cn [Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003 (China); Tian, Chongguo, E-mail: cgtian@yic.ac.cn [Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003 (China); Wang, Xiaoping [University of Chinese Academy of Sciences, Beijing 100049 (China); State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, Guangdong 510640 (China); Huang, Guopei; Fang, Yin; Zong, Zheng [Key Laboratory of Coastal Zone Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong 264003 (China); University of Chinese Academy of Sciences, Beijing 100049 (China)

    2014-11-01

    Rapid development of port and shipbuilding industry in China has badly affected the ambient air quality of coastal zone due to shipping emissions. A total of 60 ambient air samples were collected from background site of Tuoji Island in Bohai Sea strait. The air samples were analyzed for PM{sub 2.5}, organic carbon (OC), element carbon (EC), inorganic elements, and water-soluble ions. The maximum concentration of PM{sub 2.5} was observed during spring (73.6 μg·m{sup −3}) compared to winter (39.0 μg·m{sup −3}) with mean of 54.6 μg·m{sup −3}. Back trajectory air mass analysis together with temporal distribution of vanadium (V) showed that V could be the typical tracer of shipping emissions at Tuoji Island. Furthermore, the ratios of vanadium to nickel (V/Ni), vanadium to lead (V/Pb) and vanadium to zinc (V/Zn) also suggest shipping emissions at Tuoji Island. The annual average primary PM{sub 2.5} estimate of shipping emissions was 0.65 μg·m{sup −3} at Tuoji Island, accounting for 2.94% of the total primary PM{sub 2.5}, with a maximum of 3.16% in summer and a minimum of 2.39% in autumn. - Highlights: • Tracers of shipping emissions in coastal zone of northern China were identified. • Contributions of shipping emissions on primary PM{sub 2.5} were estimated. • Shipping emissions accounted for 2.94% of primary PM{sub 2.5} apart from fishing boats. • Impact of shipping emissions on coastal zone increased rapidly in recent years.

  15. Identification and quantification of shipping emissions in Bohai Rim, China

    International Nuclear Information System (INIS)

    Rapid development of port and shipbuilding industry in China has badly affected the ambient air quality of coastal zone due to shipping emissions. A total of 60 ambient air samples were collected from background site of Tuoji Island in Bohai Sea strait. The air samples were analyzed for PM2.5, organic carbon (OC), element carbon (EC), inorganic elements, and water-soluble ions. The maximum concentration of PM2.5 was observed during spring (73.6 μg·m−3) compared to winter (39.0 μg·m−3) with mean of 54.6 μg·m−3. Back trajectory air mass analysis together with temporal distribution of vanadium (V) showed that V could be the typical tracer of shipping emissions at Tuoji Island. Furthermore, the ratios of vanadium to nickel (V/Ni), vanadium to lead (V/Pb) and vanadium to zinc (V/Zn) also suggest shipping emissions at Tuoji Island. The annual average primary PM2.5 estimate of shipping emissions was 0.65 μg·m−3 at Tuoji Island, accounting for 2.94% of the total primary PM2.5, with a maximum of 3.16% in summer and a minimum of 2.39% in autumn. - Highlights: • Tracers of shipping emissions in coastal zone of northern China were identified. • Contributions of shipping emissions on primary PM2.5 were estimated. • Shipping emissions accounted for 2.94% of primary PM2.5 apart from fishing boats. • Impact of shipping emissions on coastal zone increased rapidly in recent years

  16. Nutrients concentration and changes in decade-scale in the central Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    -The nutrients contents and distributions are discussed briefly, based on the data obtained in 1998~1999. Besides explanation of the results, a 20-a time series data of nutrients and biological parameters for central Bohai Sea are reviewed. It is found that both concentration and relative content of nutrients have been changed dramatically. The increase of nitrogen and decrease of phosphate and silicate led to the dramatically increase of N/P ratio and the decrease of Si/N ratio. The situation of nitrogen limiting in central Bohai Sea is gradually changing to that of relative lack of phosphate and silicate The decrease of the Huanghe River input to the Bohai Sea may be responsible for this change. These in turn may limit the growth of diatom and thus promote the development of pyrrophyta if other conditions (e.g. temperature and hydrodynamics) are suitable. We conclude that this may be the major inducement factor of pyrrophyta red tide in the Bohai Sea.

  17. Hindcasting and forecasting macrofauna species distribution for the Jade Bay tidal basin (North Sea, Germany) in response to climatic and environmental changes

    Science.gov (United States)

    Singer, Anja; Schückel, Ulrike; Beck, Melanie; Bleich, Oliver; Brumsack, Hans-J.; Freund, Holger; Geimecke, Christina; Lettmann, Karsten; Millat, Gerald; Staneva, Joanna; Vanselow, Anna; Westphal, Heiko; Wolff, Jörg-O.; Wurpts, Andreas; Kröncke, Ingrid

    2016-04-01

    During the last decades severe climatic and environmental changes have been monitored for the Jade Bay (German Wadden Sea), causing pronounced changes in the abundance and spatial distribution of characteristic benthic species. Due to their relatively sessile habit, benthic species are ideal organisms for small-scale species distribution modelling (SDM) and important indicators for environmental changes and disturbances. In a first step, the present distribution (representing 2009) was modelled for 10 characteristic macrofauna (> 0.5 mm) species, built on statistical relations between species presences and 11 high-resolution environmental grids. Here, five different presence-absence modelling algorithms were merged (GLM, GBM, RF, MARS, ANN) within the ensemble forecasting platform 'biomod2'. In a second step, the past distribution scenario was reconstructed for the 1970s in order to evaluate the hindcast model results with independent macrofauna data from the 1970s. In a third step, the future macrofauna distribution (representing 2050) was forecasted under potential future habitat conditions, i.e. ongoing sea-level rise and changing biogenic structures (seagrass and mussel beds). Submergence time and sediment characteristics correlated most significantly with the modelled macrofauna distribution at the study site, followed by nutrient supply and topography. The historical macrofauna data evaluated the past distribution scenario model results. Climate change induced sea-level rise and its local implications on the Jade Bay (increased sediment load, rise in the tidal height) explained the changes in the macrofauna distribution patterns since the last four decades. The forecast scenario revealed clear species distribution shifts, range size changes and niche overlap changes.

  18. Paleoenvironmental changes during the late Quaternary as inferred from foraminifera assemblages in the Laizhou Bay

    Institute of Scientific and Technical Information of China (English)

    YAO Jing; YU Hongjun; XU Xingyong; YI Liang; CHEN Guangquan; SU Qiao

    2014-01-01

    Controlled by climate changes, there were three large-scale transgressions and regressions around the Bohai Sea during the late Quaternary, which were accepted by most geologists. However, a big controversy still exists about the time when the transgressions occurred separately. In order to find out the process of the paleoenvironmental changes around the Bohai Sea in the late Quaternary, the foraminifera assemblages from a new borehole Lz908 in the southern coast of the Laizhou Bay were studied, and then the transgressive strata were indentified. Combined with accelerator mass spectrometry radiocarbon 14C (AMS14C) and opti-cally stimulated luminescence (OSL) ages, the occurrence time of these transgressions were re-determined. The result showed that three major large-scale transgressions occurred separately at the beginning of ma-rine isotopic stage 7 (MIS7), the last interglacial period (MIS5) and the Holocene. In addition, a small-scale transgression occurred in the mid-MIS6, and the corresponding transgressive stratum was deposited. The transgressive deposition of MIS3 was also discovered in this study. However, the characteristics of the fora-minifera indicated the environment during this period was colder than that in the MIS5. By comparison with the global sea-level changes, the paleoenvironmental changes around the Bohai Sea in the late Quaternary can be consistent with the global climate changes.

  19. Relation Matrix of Water Exchange for Sea Bays and Its Application

    Institute of Scientific and Technical Information of China (English)

    SUN Jian; TAO Jian-hua

    2006-01-01

    Water exchange is an important hydrodynamic character of sea bays, and it is the basis for the study of the environmental capacity of sea bays. In this paper, a relation matrix is set up to describe the interaction among different areas of a sea bay, and to predict the water quality of those areas. The relation matrix is calculated based on the numerical results from a water quality model. This method is applied to the study of water exchange and the prediction of water quality of the Bohai Sea. The Bohai Sea is divided into five areas, and the effect of seasonal wind is taken into consideration. The results show a) the relation matrix can be used to study the water exchange among different areas and predict water quality of different areas at the respective characteristic time, b) the reduction of pollutant is dependent on both water exchange and initial distribution of the pollutant, and c) the half-life time of the pollutant is longer than the half-exchange time of the sea water.

  20. 环渤海地区膜法海水淡化预处理工艺探讨%Discussions on pretreatment techniques of membrane desalination at Bohai Rim Region

    Institute of Scientific and Technical Information of China (English)

    杜启云

    2011-01-01

    Seawater desalination is a major issue for the economic development in the region of Bohai Rim, Pretreatment of seawater is a key process in desalination. Based on the feature of seawater quality at Bohai Bay, the selection of pretreatment approaches and the consideration of water temperature and turbidity for membrane-based desalination were discussed. The categories and characteristics of the continuous membrane filtration technique were introduced as welL%海水淡化是环渤海地区经济发展的重大课题.海水预处理是淡化的关键过程.文章结合渤海湾地区海水水质的特点,讨论了膜法海水淡化预处理工艺的选择,设计时对水温,浊度变化的考虑.对连续膜过滤工艺的类型和特点作了介绍.

  1. CNPC and EDC(USA) Signed Petroleum Contract

    Institute of Scientific and Technical Information of China (English)

    Xia Guijiang

    1997-01-01

    @@ On June 16,1997 CNPC ( China National Petroleum Corporation) and EDC( Energy Development Corporation (China), Inc.) signed a petroleum contract on cooperatively conducting petroleum exploration and development in Chengzikou Block located in Shengli Oilfields belonging to Bohai Bay Basin.

  2. Greigite as a marker of paleo sulphate methane transition zone (SMTZ) in cold seep environment of Krishna-Godavari (KG) Basin, Bay of Bengal, India.

    Science.gov (United States)

    B, F. K.; Dewangan, P.; Usapkar, A.; Mazumdar, A.; Kocherla, M.; Tammisetti, R.; Khalap, S. T.; Satelkar, N. P.; Mehrtens, T.; Rosenauer, A.

    2014-12-01

    Rockmagnetic results and electron microscopic observations on a sediment core retrieved from a proven cold seep environment of Krishna-Godavari (KG) Basin revealed an anomalously magnetically enhanced zone (17 - 23 mbsf) below the present-day SMTZ in the KG offshore basin. This zone is characterized by higher SIRM / k, kARM / SIRM and kfd % values indicating the presence of fine grained superparamagnetic (SP) sized ferrimagnetic iron sulphides minerals such as greigite formed due to anaerobic oxidation of methane (AOM). Identification of such mineral phases and understanding the mechanism of their formation and preservation is of vital importance which could provide better understanding of the geochemical processes on the paleo - SMTZ. Magnetic concentrates extracted from this zone were characterised by transmission electron microscopy and energy dispersive X- ray spectrometry. We observed two possible occurrences of magnetic phases within this sediment depths 17 - 23 mbsf. (a) authigenically formed SP sized ferrimagnetic inclusions of magnetite, pyrite and greigite within matrix of host siliceous grain, (b) poorly crystallized fine-grained magnetite with ill defined grain boundary possibily formed extracellulary by magnetotactic bacterias through biologically-induced mineralization. High methane fluxes as observed in this basin provides suitable environment for the formation of greigite in the vicinity of SMTZ. We hypothesize that due to availability of residual iron and low supply of hydrogen sulphide caused by downwards diffusion lead to preservation of greigite. The occurence of greigite as inclusion within the host silicate matrix might explain its preservation in this zone in spite of intense pyritization. The greigite would otherwise be converted to stable-form pyrite. It is challenging to explain the origin of biologically produced magnetite within 17 - 23 mbsf as it is expected to dissolve in this zone due to intense pyritization.

  3. Evaluation of Contaminant Residues in Delaware Bay Bald Eagle Nestlings

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Bald eagle (Naliacetus leucocephalus) nesting attempts have steadily increased over the past decade in the Delaware Bay and River drainage basin; however, nesting...

  4. Upwelling features near Sri Lanka in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    ShreeRam, P; Rao, L.V.G.

    The Bay of Bengal is a semi-enclosed tropical ocean basin that is highly influenced by monsoons and receives large volume of freshwater from both river discharge and rainfall. Over the Bay of Bengal two distinct wind systems prevail during the year...

  5. Ten Main Technological Breakthroughs of CNPC in 2009

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    @@ Breakthrough in systematic technology for exploration of Qikou oil-enriched depression in Bohai Bay Basin Qikou oil-enriched depression is one of the largest depressions of the Tertiary deposit in Bohai Bay Basin.The oil and gas exploration of this area faces a number of bottlenecks,such as a large proportion of negative structures,complicated distribution of sedimentary sand bodies and diversified types of oil and gas reservoirs.

  6. Pressure Evolution and Gas Accumulation of the Fourth Member of the Shahejie Formation in Dongying Depression,Bohai Bay Basin%渤海湾盆地东营凹陷沙四下亚段地层压力演化与天然气成藏

    Institute of Scientific and Technical Information of China (English)

    刘华; 蒋有录; 宋国奇; 蔡东梅; 徐昊清

    2012-01-01

    通过实测压力、泥岩声波时差、流体包裹体古压力恢复,对东营凹陷民丰地区沙四下亚段地层压力的演化特征进行了分析。研究表明,民丰地区地层压力纵向上存在"常压—超压—常压"三段式结构;时间上,沙四下亚段地层压力具有"二旋回波动模式",即存在"常压—弱超压—常压"和"常压—超高压—常压(弱超压)"的演化过程,其中两次地层超压的形成时间与中深层天然气藏的两期成藏时间相对应,为油气藏的形成提供了动力条件。研究区地层压力的动态演化过程是多因素作用的结果,第一次高压的形成是地层快速沉积产生欠压实的结果,生烃贡献相对较小;第二次超压的形成是烃源岩大量生烃和原油裂解成天然气造成的,沉积作用为辅。由于地温梯度降低、断裂—砂体泄压、饱和气藏深埋等作用的影响,现今民丰地区沙四下储层表现为以常压为主,伴生部分超压的分布特征。%After the paleo-pressure build-up by means of measured pressure,mudstone sonic log interval and fluid inclusions,the pressure evolution model of the fourth member of the Shahejie Formation is analyzed in Minfeng area,Dongying depression.The results show that,different periods of reservoir formation correspond to different pressure system in Es4 reservoir,Minfeng area: the hydrocarbon accumulation of Sha 2-last stage of Dongying was accomplished in a higher pressure system;the hydrocarbon accumulation environment of the last stage of Ng was normal pressure;and after the middle and late period of Nm the cracking gas in the central area of sub sag was formed in a high pressure system.The dynamic evolution process of formation pressure is the results of integrated effect of multiple factors,the first high pressure was due to uncompaction of the high-rate deposition of the formation,and the hydrocarbon-generation made a little contribution;a large amount of hydrocarbon played an important part in the form of the second high pressure,in addition,the sedimentation acted as the auxiliary role.Under the influence of the decrease of geothermal gradient,fracture,sand body-pressure discharge and the deep-burial of gas reservoir,the gas reservoir founded in Sha 4 reservoir,Minfeng area is mainly normal pressure.

  7. Correlation of light hydrocarbons between source rock and crude oil:an example from Dongying and Zhanhua depressions in Jiyang subbasin,Bohai Bay Basin%烃源岩与原油中轻馏分烃的对比——以胜利油田东营、沾化凹陷为例

    Institute of Scientific and Technical Information of China (English)

    王培荣; 徐冠军; 张大江; 肖廷荣; 任冬苓

    2013-01-01

    An in-house designed and manufactured on-line analyzing device consisting of vacuum ball milling, heating releasing, helium purging and liquid nitrogen trapping was used to study the light hydrocarbon fractions ( C5 - C13 )of scattered organic matter in source rocks.Ten source rock samples and saturated hydrocarbon samples of their extracts as well as 15 oil samples from the Eocene Shahejie Formation in Dongying and Zhanhua depressions of Shengli oilfield were first analyzed by GC and GC-MS.Then oil-source and oil-oil correlation and classification of light hydrocarbon (nC6 -nC9)were performed.The results in combination with the biomarkers and geological background were finally used to perform comprehensive study,leading to four conclusions, (a) The light hydrocarbons in the scattered organic matter of the source rocks in the upper Es4 , lower Es3 and Es1 are different in chemical compositions.(b)The chemical components of C5 - C13 light hydrocarbons are related to the salinity of water column during deposition, which is consistent with that of the oils, (c) Among the 15 oil samples, 8 samples contain light hydrocarbons mostly originated from the lower Es source rocks, while 4 samples from the upper Es4 source rocks,the rest are mixed oil.(d)The on-line device provided a new way for study the characteristics of light hydrocarbons (C5 -C13)in the scattered organic matter in source rocks and their application in petroleum geochemistry.%利用自行设计研制的密闭球磨粉碎、加热解析、氦气吹扫、冷阱捕集在线分析装置,研究烃源岩中分散有机质的轻馏分烃C5-C13的化学组成.对胜利油田东营、沾化凹陷10块古近系沙河街组烃源岩和其抽提物的饱和烃组分,及15个该地区的原油样品进行了C5-C13轻馏分色谱分析和饱和烃色-质分析,然后通过岩-油nC6-nC9轻馏分对比及油-油轻馏分对比和分类,结合岩、油中“较重”的生物标志物参数及其地质背景综合研究,认为:①Es4(上),Es3(下)和Es1段烃源岩分散有机质中的轻馏分烃各有不同的化学组成特征;②烃源岩分散有机质C5-C13轻馏分的化学组成与其沉积时水体盐度之间有相关性,这种相关性与我们以前对原油的研究成果一致;③15个原油的油-岩对比说明,有8个原油的轻馏分主要源自Es3(下)段烃源岩,有4个油样的轻馏分主要源自Es4(上)段,另外7个似应为混源油;④自行设计的在线分析装置,可以为研究烃源岩分散有机质中C5-C13轻馏分的特征及其在油气地球化学方面的应用提供一个新的技术手段.

  8. Medium-deep clastic reservoirs in the slope area of Qikou sag,Huanghua depression, Bohai Bay Basin%黄骅坳陷歧口凹陷斜坡区中深层碎屑岩储集层特征

    Institute of Scientific and Technical Information of China (English)

    蒲秀刚; 卢异; 柳飒; 周立宏; 王文革; 韩文中; 肖敦清; 刘海涛; 陈长伟; 张伟; 袁选俊

    2013-01-01

    To get a better understanding of the distribution pattern of favorable reservoir belts in the medium-deep clastic rocks in the Qikou sag of the Huanghua depression, and find out premium reservoir zone, the characteristics and controlling factors of the medium-deep reservoirs in the Qikou sag were analyzed. Comprehensive study into the structural setting, provenance, depositional system, and reservoir properties shows that the Paleogene in the Qikou sag has multi-sags and multi-slopes, with slopes accounting for over 70% of the total sag area. A number of large braided river (fan) delta front - gravity flow sand bodies matching with multi-slope zones lay a good material foundation for the formation of medium-deep effective reservoirs there. Generally buried at over 2500 m, the medium-deep clastic rocks are mainly lithic feldspathic sandstone, with secondary pores and cracks as major reservoir space. Being in the medium diagenesis evolution stage, the medium-deep clastic rocks in the Qikou sag span over a large depth. Nine major factors affecting reservoir properties have been identified by mathematical geology. Although the medium-deep clastic rock interval is poor in physical properties and complex in pore structure, high sedimentation rate, medium geothermal field, high fluid pressure, high feldspar content, relatively high dissolution rate and early oil and gas charge have given rise to three to four belts with abnormally high porosity in it, which are all favorable hydrocarbon reservoir zones.%为了查明渤海湾盆地黄骅坳陷歧口凹陷斜坡区中深层碎屑岩有利储集相带分布规律,寻找相对优质的储集层段,对歧口凹陷中深层开展储集层特征及控制因素分析.构造背景、物源、沉积体系、储集性能综合研究表明,歧口凹陷古近系具有多凹多坡的地质特点,各类斜坡区占全凹陷面积70%以上;来自盆内外物源的多个大型辫状河(扇)三角洲前缘-重力流砂带与多类斜坡区匹配,为歧口凹陷斜坡区中深层油气有效储集层的形成奠定了良好的物质基础;中深层碎屑岩埋深一般大于2500 m,主要为岩屑长石类砂岩,以次生孔-缝储集空间为主.歧口凹陷中深层碎屑岩整体处于中成岩演化阶段,该阶段跨越深度范围较大,储集物性的主控因素可以通过数学地质的方法识别出9项,虽其总体物性较差、孔隙结构复杂,但较高的沉降速率、中等地温场、高流体压力、高长石含量、较高溶蚀率、早期烃类充注等有利因素促使中深层碎屑岩发育纵向延伸上千米的3~4个异常高孔隙带,均是有利的油气储集层段.

  9. Study on Karst Development Pattern Based on FMI Logging Facies:A Case Study of Paleozoic Strata in Nanpu Sag of Huanghua Depression, Bohai Bay Basin%基于FMI测井相的岩溶发育模式——以渤海湾盆地黄骅坳陷南堡凹陷古生界为例

    Institute of Scientific and Technical Information of China (English)

    王晔磊; 邱隆伟; 师政; 曹中宏; 张红尘

    2016-01-01

    碳酸盐岩潜山油气藏是南堡凹陷最为重要的油气藏类型,岩溶作用对其具有控制作用.为了增强对南堡凹陷岩溶发育规律的认识,以FMI测井资料为主,结合常规测井、录井以及岩石薄片等地质资料,总结岩溶发育控制因素的FMI测井响应特征,建立了高阻裂缝相、高导裂缝相、溶蚀扩大缝相、溶蚀孔隙相和洞穴垮塌相5种FMI测井相.通过数据统计,建立了岩溶发育特征与FMI测井相的配置关系.研究结果表明,南堡凹陷发育上部表生岩溶带和下部埋藏岩溶带,表生岩溶带主要发育高导裂缝相、溶蚀孔隙相和洞穴垮塌相,其中,洞穴垮塌相是表生岩溶带特有;埋藏岩溶带主要发育高阻裂缝相、溶蚀扩大缝相、溶蚀孔隙相.岩性与断层是岩溶发育最主要的控制因素.

  10. STUDY ON SELECTION OF PRETREATMENT PROCESSES FOR SEAWATER DESALINATION BY RO IN TIANJIN'S BOHAI GULF%天津渤海湾反渗透海水淡化预处理工艺选择研究

    Institute of Scientific and Technical Information of China (English)

    郭兴芳; 陈立; 李伟; 王圆生; 陶润先; 王岩芳

    2011-01-01

    天津渤海湾近岸海水水质进行了长期跟踪监测分析,根据水质特性,选用不同物化工艺和生物工艺进行海水预处理试验,研究不同工艺作为反渗透海水淡化预处理的适用性.结果表明,天津渤海湾近岸海水以有机污染为主,有机污染较严重,相对分子质量低的溶解性有机物质量分数在80%以上;反渗透海水淡化预处理宜选择能有效去除相对分子质量低的溶解性有机物的工艺技术,可对生物活性炭、膜过滤等工艺技术进行集成优化.%A long track and water quality analysis was monitored of Tianjin Bohai Bay coastal seawater. According to water quality characteristics, different physical and chemical processes and biological processes was used for water pre-treatment experiment to study the different processes as reverse osmosis desalination pretreatment applicability. The results showed that the coastal water of Tianjin Bohai Bay was mainly polluted by organic matter which was serious, low dissolved organic matter of low molecular weight was more than 80%, reverse osmosis desalination pre-treatment should be selected to effectively remove the relative low molecular organic matter which can integrated optimize biological activated carbon and membrane filtration technology.

  11. Structural characteristics and evolution of Rakhine Basin, Bay of Bengal%孟加拉湾若开盆地构造特征及演化

    Institute of Scientific and Technical Information of China (English)

    王雪峰; 吕福亮; 范国章; 邵大力; 孙辉; 唐鹏程

    2013-01-01

    This paper analyzes the structural characteristics and tectonic evolution of Rakhine Basin based on 2D seismic data and well data.The basin is located at accretionary wedge with a trench setting of active continental margin and has experienced the embryonic stage (Late CretaceousPaleocene),collision stage (Eocene-Oligocene) and quick collision stage (Miocene-Pliocene).Rakhine Basin can be subdivided into the submarine plain in the west and the Rakhine fold belt in the east.The Rakhine fold belt consists of the northern compressive fold belt and the southern strike-slip fault belt.In the northern compressive fold belt develop a lot of NNW-trending linear folds that can be subdivided into steep folds with high amplitude caused by the intensive tectonic deformation from east to west.In the southern strike-slip fault belt,some anticlines form along the strike-slip fault and the unambiguous flower structures.The evolution of the regional section suggests that the deformation began at the end of Late Miocene,and became intensive from the end of Pliocene to Quaternary.The structures in the east are older and more intensive than that of the west due to the regional contraction from east to west and the deformational propagation westward.The deposition center migrated from east to west after Miocene formation deposited.All the characteristics of Rakhine Basin are mainly controlled by different stress patterns caused by the subduction formed between the Indian-Australia plate and the Eurasia plate.%根据地震、钻井等基础资料建立主干剖面,结合平面构造展布及剖面构造特征研究孟加拉湾若开盆地的构造特征和演化.若开盆地是一个主动大陆边缘海沟背景下的增生楔盆地,经历了晚白垩世-古新世早期发育期、始新世-渐新世缓慢碰撞期和中新世-上新世盆地定型期3个区域演化阶段.平面上划分为东部的若开褶皱带和西部的海底平原带.若开褶皱带具有南北分段

  12. Exchange fluxes of nutrients between sediment and sea water in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Investigations of sediment-water fluxes of nutrients in the Bohai Sea were carried out in September-October 1998 and April- May 1999. The exchange fluxes of nutrients between sediment and sea water were determined by incubating the core-top sediments with overlying water aerated with air. The benthic fluxes of NO3 -, NO2-, Ni4 + , DIN, DON and TDN in the first cruise and the flux es of NO3-, NO2-, NH4 + , DIN, DON, TDN, PO43-, DOP and TDP in the second cruise were measured. The exchange fluxes of nutrients in fall were higher than in spring. The benthic nutrient fluxes represented 15 % ~ 55 % of nutrient budgets in the Bohai Sea.

  13. Origins and features of oil slicks in the Bohai Sea detected from satellite SAR images.

    Science.gov (United States)

    Ding, Yi; Cao, Conghua; Huang, Juan; Song, Yan; Liu, Guiyan; Wu, Lingjuan; Wan, Zhenwen

    2016-05-15

    Oil slicks were detected using satellite Synthetic Aperture Radar (SAR) images in 2011. We investigated potential origins and regional and seasonal features of oil slick in the Bohai Sea. Distance between oil slicks and potential origins (ships, seaports, and oil exploitation platforms) and the angle at which oil slicks move relative to potential driving forces were evaluated. Most oil slicks were detected along main ship routes rather than around seaports and oil exploitation platforms. Few oil slicks were detected within 20km of seaports. Directions of oil slicks movement were much more strongly correlated with directions of ship routes than with directions of winds and currents. These findings support the premise that oil slicks in the Bohai Sea most likely originate from illegal disposal of oil-polluted wastes from ships. Seasonal variation of oil slicks followed an annual cycle, with a peak in August and a trough in December. PMID:26988390

  14. Modeling of the Bohai oilfield engineering geology demonstration information system based on digital seabed technology

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In this paper, the framework and technologic process of engineering geology demonstration information system (EGDIS) of the Bohai oilfield are presented, and the key technologies for system modeling,such as storage and processing technology of multi-source and heterogeneous data, integrated display technology of multi-source information and multiple safeguard system design are studied. EGDIS of the Bohai oilfield is an integrated application system based on the data standardization and digital seabed database,has the function to realize the standardization/conformity, input/output, inquiry and display of the multisource and heterogeneous data and graphics, and provides multiple comprehensive analysis and application services, which will provide shared and scientific basic data for the marine engineering construction and oilfield engineering safeguard.

  15. A Case Study for a Digital Seabed Database:Bohai Sea Engineering Geology Database

    Institute of Scientific and Technical Information of China (English)

    SU Tianyun; ZHAI Shikui; LIU Baohua; LIANG Ruicai; ZHENG Yanpeng; WANG Yong

    2006-01-01

    This paper discusses the designing plan of ORACLE-based Bohai Sea engineering geology database structure from requisition analysis, conceptual structure analysis, logical structure analysis, physical structure analysis and security designing.In the study, we used the object-oriented Unified Modeling Language (UML) to model the conceptual structure of the database and used the powerful function of data management which the object-oriented and relational database ORACLE provides to organize and manage the storage space and improve its security performance.By this means, the database can provide rapid and highly effective performance in data storage, maintenance and query to satisfy the application requisition of the Bohai Sea Oilfield Paradigm Area Information System.

  16. Origins and features of oil slicks in the Bohai Sea detected from satellite SAR images.

    Science.gov (United States)

    Ding, Yi; Cao, Conghua; Huang, Juan; Song, Yan; Liu, Guiyan; Wu, Lingjuan; Wan, Zhenwen

    2016-05-15

    Oil slicks were detected using satellite Synthetic Aperture Radar (SAR) images in 2011. We investigated potential origins and regional and seasonal features of oil slick in the Bohai Sea. Distance between oil slicks and potential origins (ships, seaports, and oil exploitation platforms) and the angle at which oil slicks move relative to potential driving forces were evaluated. Most oil slicks were detected along main ship routes rather than around seaports and oil exploitation platforms. Few oil slicks were detected within 20km of seaports. Directions of oil slicks movement were much more strongly correlated with directions of ship routes than with directions of winds and currents. These findings support the premise that oil slicks in the Bohai Sea most likely originate from illegal disposal of oil-polluted wastes from ships. Seasonal variation of oil slicks followed an annual cycle, with a peak in August and a trough in December.

  17. Numerical Study on Density Residual Currents of the Bohai Sea in Summer

    Institute of Scientific and Technical Information of China (English)

    刘桂梅; 王辉; 孙松; 韩博平

    2003-01-01

    M2 tide and density residual currents in the Bohai Sea were examined using the Blumberg and Mellor 3D nonlinear numerical coastal circulation model incorporating Mellor and Yamada level 2.5 turbulent closure model. The tidal results showed good agreement with previous work. The model results indicated that the density residual currents are robust in summer; and that at the transition zone between well mixed and stratified water, the horizontal velocity is high and the vertical velocity is positive.

  18. Sino-US Cooperation in Offshore Oil and Gas Exploration of Bohai Gulf

    Institute of Scientific and Technical Information of China (English)

    Mao Zefeng

    1994-01-01

    @@ Through bilateral negotiation China Oil and Gas Exploration and Development Corp.and Louisiana Exploration Corp. of US signed a contract on the oil exploration in Zhaodong area in the shallow sea of Bohai Gulf on January 1993 in the Great People's Hall, Beijing. It is a new area of the onshore oil sector opened to the Sinoforeign cooperation, following 11 southern provinces of China, which were opened for foreigners to run risk exploration for oil resource and cooperative development.

  19. Sea ice thickness estimation in the Bohai Sea using geostationary ocean color imager data

    Institute of Scientific and Technical Information of China (English)

    LIU Wensong; SHENG Hui; ZHANG Xi

    2016-01-01

    A method to estimate the thickness of the sea ice of the Bohai Sea is proposed using geostationary ocean color imager (GOCI) data and then applied to the dynamic monitoring of the sea ice thickness in the Bohai Sea during the winter of 2014 to 2015. First of all, a model is given between the GOCI shortwave broadband albedo and the reflectance of each band with high temporal resolution GOCI data. Then, the relationship model between the sea ice thickness and the GOCI shortwave broadband albedo is established and applied to the thickness extraction of the sea ice in the Bohai Sea. Finally, the sea ice thickness extraction method is tested by the results based on the MODIS data, thermodynamic empirical models (Lebedev and Zubov), and thein situ ice thickness data. The test results not only indicated that the sea ice thickness retrieval method based on the GOCI data was a good correlation (r2>0.86) with the sea ice thickness retrieved by the MODIS and thermodynamic empirical models, but also that the RMS is only 6.82 cm different from the thickness of the sea ice based on the GOCI andin situ data.

  20. Occurrence of microplastics in the beach sand of the Chinese inner sea: the Bohai Sea.

    Science.gov (United States)

    Yu, Xubiao; Peng, Jinping; Wang, Jundong; Wang, Kan; Bao, Shaowu

    2016-07-01

    The occurrence of microplastics in the beach sand of the Bohai Sea was investigated for the first time. The Bohai Sea is the largest Chinese inner sea and its coastal region is one of the most densely urbanized and industrialized zones of China. Samples from three costal sites (i.e., Bijianshan, Xingcheng and Dongdaihe) were collected, quantified and identified for microplastic analysis. Effects of sample depth and tourism activity were investigated. Surface samples (2 cm) contained higher microplastic concentrations than deep samples (20 cm). Samples from the bathing beach exhibited higher microplastic concentrations than the non-bathing beach, suggesting the direct contribution of microplastics from tourism activity. Of eight types of microplastics that were found, PEVA (polyethylene vinyl acetate), LDPE (light density polyethylene) and PS (polystyrene) were the largest in abundances. Moreover, the non-plastic items from samples were analyzed and results revealed that the majority abundance of the observed non-plastics were viscose cellulose fibers. Further studies are required to evaluate the environmental hazards of microplastics, especially as they may "act as a contaminant transporter" to the Bohai Sea ecosystem. PMID:27149149

  1. Benthic nutrient recycling in shallow coastal waters of the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    LIU Sumei; ZHANG Jing; CHEN Hongtao; T. Raabe

    2004-01-01

    Sediment-water fluxes of N and P species in the Bohai Sea were investigated in September-October 1998 and April-May 1999. The benthic fluxes of nutrient species were determined by incubating sediment core samples with bottom seawater bubbled with air or nitrogen.NO2-,NH4+,dissolved organic nitrogen (DON) and phosphorus (DOP), total dissolved nitrogen (TDN) and phosphorus (TDP), and showed a net exchange flux from seawater to sediment, while , dissolved inorganic nitrogen (DIN) and were released from sediment to seawater in the Bohai Sea. Sediment-water nutrient exchange increases DIN and reduces the phosphorus load in the Bohai Sea. The release of silicate from sediment to overlying seawater reduces potential silicate limitation of primary production resulted from decrease of riverine discharge. The exchange flux of nutrients showed no obvious seasonal variation. The present study showed that the concentrations and composition of nutrients in the water column were affected by suspended sediment, and that not all the exchangeable phosphate in sediment could be released via sediment resuspension.

  2. Modeling Study of Seasonal Variation of the Pelagic-Benthic Ecosystem Characteristics of the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Based on experiment data of the Sino-German comprehensive investigations in the Bohai Sea in 1998 and 1999, a simple coupled pelagic-benthic ecosystem multi-box model is used to simulate the ecosystem seasonal variation. The pelagic sub-model consists of seven state variables: phytoplankton, zooplankton, TIN, TIP, DOC, POC and dissolved oxygen (DO). The benthic sub-model includes macro-benthos, meiobenthos, bacteria, detritus, TIN and TIP in the sediment. Besides the effects of solar radiation, water temperature and the nutrient from sea bottom exudation, land-based inputs are considered. The impact of the advection terms between the boxes is also considered. Meanwhile, the effects of the microbial-loop are introduced with a simple parameterization. The seasonal variations and the horizontal distributions of the ecosystem state variables of the Bohai Sea are simulated. Compared with the observations, the results of the multi-box model are reasonable. The modeled results show that about 13% of the photosynthesis primary production goes to the main food loop, 20% transfers to the benthic domain, 44% is consumed by the respiration of phytoplankton, and the rest goes to DOC. Model results also show the importance of the microbial food loop in the ecosystem of the Bohai Sea, and its contribution to the annual zooplankton production can be 60% - 64%.

  3. Taxonomic Distinctness of Macrofauna as an Ecological Indicator in Laizhou Bay and Adjacent Waters

    Institute of Scientific and Technical Information of China (English)

    ZHOU Hong; HUA Er; ZHANG Zhinan

    2010-01-01

    In this paper,we assessed the ecological and biodiversity status in the Bohai Sea through a quantitative survey on macrofaunal community at 25 stations in Laizhou Bay and adjacent waters in the autumn of 2006.We tested the robustness and effectiveness of taxonomic distinctness as an ecological indictor by analyzing its correlation with species richness and natural environmental variables and by analyzing other ecological indicators(Shannon-Wiener H' and W statistics from Abundance Biomass Comparison curve).Results so obtained indicated that the benthic environment of the study waters in general is not under major impact of anthropogenic disturbance,but some stations in Laizhou Bay and along the coast of the Shandong Peninsula and even in the central Bohai Sea might be moderately disturbed and showed signs of ecological degradation.The taxonomic distinctness measures △+ and Λ+ were independent of sampling effort and natural environment factors and were compliant to other ecological indicators.Further application of the taxonomic distinctness indicator to assess marine biodiversity and ecosystem health on a larger regional scale with historical data seems promising.

  4. A three-dimensional coupled physical-biological model study in the spring of 1993 in the Bohai Sea of China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A three-dimensional (3-D) coupled physical and biological model was used to investigate the physical processes and their influence on the ecosystem dynamics of the Bohai Sea of China. The physical processes include M2 tide, time-varying wind forcing and river discharge. Wind records from 1 to 31 May in 1993 were selected to force the model. The biological model is based on a simple, nitrate and phosphate limited, lower trophic food web system. The simulated results showed that variation of residual currents forced by M2 tide, river discharge and time-varying wind had great impact on the distribution of phytoplankton biomass in the Laizhou Bay. High phytoplankton biomass appeared in the upwelling region. Numerical experiments based on the barotropic model and baroclinic model with no wind and water discharge were also conducted. Differences in the results by the baroclinic model and the barotropic model were significant: more patches appeared in the baroclinic model comparing with the barotropic model. And in the baroclinic model, the subsurface maximum phytoplankton biomass patches formed in the stratified water.

  5. SSU rDNA sequence diversity and seasonally differentiated distribution of nanoplanktonic ciliates in neritic Bohai and Yellow Seas as revealed by T-RFLP.

    Directory of Open Access Journals (Sweden)

    Jun Dong

    Full Text Available Nanociliates have been frequently found to be important players in the marine microbial loop, however, little is known about their diversity and distribution in coastal ecosystems. We investigated the molecular diversity and distribution patterns of nanoplanktonic oligotrich and choreotrich (OC ciliates in surface water of three neritic basins of northern China, the South Yellow Sea (SYS, North Yellow Sea (NYS, and Bohai Sea (BS in June and November 2011. SSU rRNA gene clone libraries generated from three summertime samples (sites B38, B4 and H8 were analyzed and revealed a large novel ribotype diversity, of which many were low-abundant phylotypes belonging to the subclass Oligotrichia, but divergent from described morphospecies. Based on the data of terminal-restriction fragment length polymorphism (T-RFLP analysis of all 35 samples, we found that the T-RF richness was generally higher in the SYS than in the BS, and negatively correlated with the molar ratio of P to Si. Overall, multidimensional scaling and permutational multivariate analysis of variance of the community turnover demonstrated a distinct seasonal pattern but no basin-to-basin differentiation across all samples. Nevertheless, significant community differences among basins were recognized in the winter dataset. Mantel tests showed that the environmental factors, P:Si ratio, water temperature and concentration of dissolved oxygen (DO, determined the community across all samples. However, both biogeographic distance and environment shaped the community in winter, with DO being the most important physicochemical factor. Our results indicate that the stoichiometric ratio of P:Si is a key factor, through which the phytoplankton community may be shaped, resulting in a cascade effect on the diversity and community composition of OC nanociliates in the N-rich, Si-limited coastal surface waters, and that the Yellow Sea Warm Current drives the nanociliate community, and possibly the

  6. Exploration Status and Major Controlling Factors of Hydrocarbon Accumulation in the Continental Margin Basins of the Bengal Bay%孟加拉湾地区大陆边缘盆地勘探概况与油气富集主控因素

    Institute of Scientific and Technical Information of China (English)

    朱光辉; 李林涛

    2012-01-01

    The Bengal Bay lies in the east of India continent, west of Burma-Andaman-Sumatra area, and south of the Bangladesh. There are two different kinds of continental margins: passive and active continental margin. Many hydrocarbons bearing basins lie in the continental margins of the Bengal Bay, Based on the structure characteristics and plate position, we divided the basins into three types: passive continental margin basin (Mahanadi, Cauvery, and the K-G basins) , active continental margin basin (Rakhine, central Burma, Moattama, Andaman, and the north Sumatra basins) and remnant ocean basin (Bengal Basin). According to the distribution of the volcanic arcs, we further divided the active continental basin into trench, fore-arc and back-arc related basin. Through petroleum exploration analysis of the continental margin basins of the Bengal Bay, we come into the conclusion that the type of hydrocarbon source rocks and abundance of organic matters determined the nature of fluids and abundance of resources. Large river-delta system determined the distribution of big hydrocarbon field. Finally type, property and intensity of tectonic activities (especially of the late stage) determined the potential of exploration zones.%孟加拉湾位于印度大陆以东、缅甸—安达曼—苏门答腊以西、孟加拉国南部海上地区,该区存在主动和被动两种不同类型的大陆边缘,并发育众多大陆边缘含油气盆地.根据板块位置和构造特征将其划分为三大类,分别是:被动大陆边缘盆地(马哈纳迪、K-G和高韦里盆地);主动大陆边缘盆地(若开、缅甸中央、马达班、安达曼和北苏门答腊盆地);残留洋盆地(孟加拉盆地).根据火山岛弧带分布情况进一步将主动大陆边缘盆地划分为:①海沟型——若开盆地;②弧前型——缅甸中央盆地;③弧后型——马达班、安达曼和北苏门答腊盆地.对这些盆地油气勘探情况的统计与分析表明,该区大

  7. Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China

    Science.gov (United States)

    Liu, Jihua; Hu, Ningjing; Shi, Xuefa

    2015-04-01

    Characterization and source apportionment of polycyclic aromatic hydrocarbons (PAHs) in Sediments from the Bohai Sea, China Liu Jihua, Hu Ningjing, Shi Xuefa First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China Polycyclic aromatic hydrocarbons (PAHs) are a class of ubiquitous organic contaminants in the environment. Indeed, 16 PAH compounds have been listed as priority pollutants by the United States Environmental Protection Agency and the European Union because of their potential toxicity to humans and ecosystems. As POPs are released or escape into the environment, their global accumulation in marine sediments generates a complex balance between inputs and outputs. Furthermore, PAHs in coastal sediments can serve as effective tracers of materials transport from land-to-sea (Fang et al., 2009). Hence, investigations of PAHs in sediments can provide useful information for further understanding of environmental processes and material transport. In this study, sixteen polycyclic aromatic hydrocarbons (PAHs) were extracted from a total of 112 surface sediment samples collected across the entire territory of the Bohai Sea. The detectable concentrations of PAHs ranged from 97.2 to 300.7 ng/g across all samples, indicating low contamination levels of PAHs compared with reported values for other coastal sediments in China and developed countries. The highest concentrations were found within three belts in the vicinity of Luan River Estuary-Qinhuangdao Harbor, the Cao River Estuary-Bohai Sea Center, and north of the Yellow River Estuary. The distribution patterns of PAHs and source identification implied that PAH contamination in the Bohai Sea mainly originates from offshore oil exploration, sewage discharge from rivers and shipping activities. Further Principal components analysis (PCA)/multivariate linear regression (MLR) analysis suggested that the contributions of spilled oil products (petrogenic), coal combustion and traffic

  8. Assessing pollution-related effects of oil spills from ships in the Chinese Bohai Sea.

    Science.gov (United States)

    Liu, Xin; Guo, Mingxian; Wang, Yebao; Yu, Xiang; Guo, Jie; Tang, Cheng; Hu, Xiaoke; Wang, Chuanyuan; Li, Baoquan

    2016-09-15

    An analysis of the effects of potential oil spills will provide data in support of decisions related to improving the response to oil spills and its emergency management. We selected the Chinese Bohai Sea, especially the Bohai Strait, as our investigation region to provide an assessment of the effects of pollution from ship-related oil spills on adjacent coastal zones. Ship-related accidents are one of the major factors causing potential oil spills in this area. A three dimensional oil transport and transformation model was developed using the Estuary, Coastal, and Ocean Model. This proposed model was run 90 times and each run lasted for 15days to simulate the spread and weathering processes of oil for each of four potential spill sites, which represented potential sites of ship collisions along heavy traffic lanes in the Bohai Sea. Ten neighboring coastal areas were also considered as target zones that potentially could receive pollutants once oil spilled in the study areas. The statistical simulations showed that spills in winter were much worse than those in summer; they resulted in very negative effects on several specific target zones coded Z7, Z8, Z9, and Z10 in this paper. In addition, sites S3 (near the Penglai city) and S4 (near the Yantai city) were the two most at-risk sites with a significantly high probability of pollution if spills occurred nearby during winter. The results thus provided practical guidelines for local oil spill prevention, as well as an emergency preparedness and response program.

  9. Assessing pollution-related effects of oil spills from ships in the Chinese Bohai Sea.

    Science.gov (United States)

    Liu, Xin; Guo, Mingxian; Wang, Yebao; Yu, Xiang; Guo, Jie; Tang, Cheng; Hu, Xiaoke; Wang, Chuanyuan; Li, Baoquan

    2016-09-15

    An analysis of the effects of potential oil spills will provide data in support of decisions related to improving the response to oil spills and its emergency management. We selected the Chinese Bohai Sea, especially the Bohai Strait, as our investigation region to provide an assessment of the effects of pollution from ship-related oil spills on adjacent coastal zones. Ship-related accidents are one of the major factors causing potential oil spills in this area. A three dimensional oil transport and transformation model was developed using the Estuary, Coastal, and Ocean Model. This proposed model was run 90 times and each run lasted for 15days to simulate the spread and weathering processes of oil for each of four potential spill sites, which represented potential sites of ship collisions along heavy traffic lanes in the Bohai Sea. Ten neighboring coastal areas were also considered as target zones that potentially could receive pollutants once oil spilled in the study areas. The statistical simulations showed that spills in winter were much worse than those in summer; they resulted in very negative effects on several specific target zones coded Z7, Z8, Z9, and Z10 in this paper. In addition, sites S3 (near the Penglai city) and S4 (near the Yantai city) were the two most at-risk sites with a significantly high probability of pollution if spills occurred nearby during winter. The results thus provided practical guidelines for local oil spill prevention, as well as an emergency preparedness and response program. PMID:27357917

  10. The microwave scattering characteristics of sea ice in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    LIU Meijie; DAI Yongshou; ZHANG Jie; ZHANG Xi; MENG Junmin; ZHU Xiuqin; YIN Yalei

    2016-01-01

    Microwave remote sensing has become the primary means for sea-ice research, and has been supported by a great deal of field experiments and theoretical studies regarding sea-ice microwave scattering. However, these studies have been barely carried in the Bohai Sea. The sea-ice microwave scattering mechanism was first developed for the thin sea ice with slight roughness in the Bohai Sea in the winter of 2012, and included the backscattering coefficients which were measured on the different conditions of three bands (L, C and X), two polarizations (HH and VV), and incident angles of 20° to 60°, using a ground-based scatterometer and the synchronous physical parameters of the sea-ice temperature, density, thickness, salinity, and so on. The theoretical model of the sea-ice electromagnetic scattering is obtained based on these physical parameters. The research regarding the sea-ice microwave scattering mechanism is carried out through two means, which includes the comparison between the field microwave scattering data and the simulation results of the theoretical model, as well as the feature analysis of the four components of the sea-ice electromagnetic scattering. It is revealed that the sea-ice microwave scattering data and the theoretical simulation results vary in the same trend with the incident angles. Also, there is a visible variant in the sensitivity of every component to the different bands. For example, the C and X bands are sensitive to the top surface, the X band is sensitive to the scatterers, and the L and C bands are sensitive to the bottom surface, and so on. It is suggested that the features of the sea-ice surfaces and scatterers can be retrieved by the further research in the future. This experiment can provide an experimental and theoretical foundation for research regarding the sea-ice microwave scattering characteristics in the Bohai Sea.

  11. Bayes and empirical Bayes: do they merge?

    CERN Document Server

    Petrone, Sonia; Scricciolo, Catia

    2012-01-01

    Bayesian inference is attractive for its coherence and good frequentist properties. However, it is a common experience that eliciting a honest prior may be difficult and, in practice, people often take an {\\em empirical Bayes} approach, plugging empirical estimates of the prior hyperparameters into the posterior distribution. Even if not rigorously justified, the underlying idea is that, when the sample size is large, empirical Bayes leads to "similar" inferential answers. Yet, precise mathematical results seem to be missing. In this work, we give a more rigorous justification in terms of merging of Bayes and empirical Bayes posterior distributions. We consider two notions of merging: Bayesian weak merging and frequentist merging in total variation. Since weak merging is related to consistency, we provide sufficient conditions for consistency of empirical Bayes posteriors. Also, we show that, under regularity conditions, the empirical Bayes procedure asymptotically selects the value of the hyperparameter for ...

  12. Technical Efficiency and Port Competition: Revisiting the Bohai Economic Rim, China

    Directory of Open Access Journals (Sweden)

    Grace Wang

    2012-12-01

    Full Text Available The Bohai Economic Rim plays an important role in supporting China’s economic growth. For this research, we selected nine main ports in the region to study whether intra-port competition or corporatization would improve efficiency. Using a panel fixed effect model and stochastic frontier model, we found that the technical efficiency of selected ports is significantly influenced by the time of the initial public offering than by regional competition. The results are supportive and encouraging for policy makers to move toward the decentralized port governance in China.

  13. Signing New Contracts for Laopu and Getuo Blocks of Bohai Gulf

    Institute of Scientific and Technical Information of China (English)

    Pengpeng

    1995-01-01

    @@ CNPC and the operation group of Kerr-McGee Corp.and Energy Development Corp.(EDC) have signed the petroleum Contracts for cooperative exploitation of petroleum resources in Getuo and Laopu blocks of Bohai Gulf in Beijing on July 21, 1995. Mr. Zhou Yongkang, Vice President of CNPC, Mr. M. G. Webb, Vice President of Kerr-McGee Corp. and Mr. M. J. Phelan, officer of EDC signed document of contracts respectively. Up to now, the thirteen petroleum contracts have been signed by CNPC and foreign petroleum companies.

  14. COMPARISON OF THE EULERIAN AND LAGRANGIAN TIDAL RESIDUALS IN THE BOHAI SEA

    Institute of Scientific and Technical Information of China (English)

    魏皓; 赵亮; 冯士笮

    2001-01-01

    Tidal residual is very important to the transport of water particles, nutrients, plank-ton, etc. in the coastal sea. Eulerian scheme and Lagrangian scheme are two different ways to get the time averaged residual. Solution of the Bohai Sea's hydrodynamic system using a semi-implicit layer aver-aged numerical model yielded different direction Eulerian and Lagrangian tidal residuals. The latter were stronger than the former in most sea areas. Their different directions produced different ciretdation pattern in some areas. Compared with the Eulerian residual, the Lagranglan residual seemed to be more in accord with the observation.

  15. COMPARISON OF THE EULERIAN AND LAGRANGIAN TIDAL RESIDUALS IN THE BOHAI SEA

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Tidal residual is very important to the transport of water particles, nutrients, plankton, etc. in the coastal sea. Eulerian scheme and Lagrangian scheme are two different ways to get the time averaged residual. Solution of the Bohai Sea's hydrodynamic system using a semi-implicit layer averaged numerical model yielded different direction Eulerian and Lagrangian tidal residuals. The latter were stronger than the former in most sea areas. Their different directions produced different circulation pattern in some areas. Compared with the Eulerian residual, the Lagrangian residual seemed to be more in accord with the observation.

  16. San Diego Bay Bibliography

    OpenAIRE

    Brueggeman, Peter

    1994-01-01

    The San Diego Bay Bibliography references the scientific & gray literature on the Bay up through 1994 and it is NOT current. Compiled from numerous resources (including Hubbs-Sea World Research Institute, Regional Water Quality Control Board, & local library catalogs), it is not comprehensive since so the Bay literature is elusive. In addition, there can be duplicate references varying in completeness. The San Diego Bay Bibliography is the outcome of discussion and networking within ...

  17. An Analysis and Modeling Study of a Sea Fog Event over the Yellow and Bohai Seas

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this study, a sea fog event which occurred on 27 March 2005 over the Yellow and Bohai Seas was investigated observationally and numerically. Almost all available observational data were used, including satellite imagery of Geostationary Operational Environmental Satellite (GOES)-9, three data sets from station observations at Dandong, Dalian and Qingdao, objectively reanalyzed data of final run analysis (FNL) issued by the National Center for Environmental Prediction (NCEP) and Regional Atmospheric Modeling System (RAMS) results. Synoptic conditions and fog characteristics were analyzed. The fog formed when warm,moist air was advected northwards over the cool water of the Yellow and Bohai Seas, and dissipated when a cold front brought northerly winds and cool, dry air. In order to better understand the fog formation mechanism, a high-resolution RAMS modeling with a 6km×6km grid, initialized and validated by FNL data, was designed. A 48h modeling that started from 12 UTC 26 March 2005reproduced the main characteristics of this sea fog event. The simulated lower visibility area agreed reasonably well with the sea fog region identified from the satellite imagery. Advection cooling effect seemed to play a significant role in the fog formation.

  18. On the surface roughness characteristics of the land fast sea-ice in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    LIU Chengyu; CHAO Jinlong; GU Wei; LI Lantao; XU Yingjun

    2014-01-01

    The surface roughness characteristics (e.g., height and slope) of sea ice are critical for determining the pa-rameters of an electromagnetic scattering, a surface emission and a surface drag coefficients. It is also im-portant in identifying various ice types, retrieval ice thickness, surface temperature and drag coefficients from remote sensing data. The point clouds (a set of points which are usually defined by X, Y, and Z coor-dinates that represents the external surface of an object on earth) of land fast ice in five in situ sites in the eastern coast Bohai Sea were measured using a laser scanner-Trimble GX during 2011-2012 winter season. Two hundred and fifty profiles selected from the point clouds of different samples have been used to calcu-late the height root mean square, height skewness, height kurtosis, slope root mean square, slope skewness and slope kurtosis of them. The root mean square of the height, the root mean square of the slope and the correlation length are about 0.090, 0.075 and 11.74 m, respectively. The heights of 150 profiles in three sites manifest the Gaussian distribution and the slopes of total 250 profiles distributed exponentially. In addition, the fractal dimension and power spectral density profiles were calculated. The results show that the fractal dimension of land fast ice in the Bohai Sea is about 1.132. The power spectral densities of 250 profiles can be expressed through an exponential autocorrelation function.

  19. Research on the seismic fortification level of offshore platform in Bohai Sea and adjacent areas

    Institute of Scientific and Technical Information of China (English)

    PENG Yan-ju; L(U) Yue-jun; TANG Rong-yu; SHA Hai-jun

    2005-01-01

    API code is introduced at first, and then a comparison of seismic character and seismic hazard between Bohai and Southern California is carried out. The analysis indicates both the seismic frequency and intensity and the seismic hazard of Bohai are much weaker than that of Southern California. API code states the strength level and deformation level of permanent structures in Southern California takes 200 a and several hundred to a few thousand years respectively. But in the reference codes in China, the seismic levels take 500 a and 10 000 a for strength design and deformation design, and it seems too conservative. In China, the deformation level of class A structure takes 2%~3% probabilities of exceedance in reference period 100 a, and that of class B and C often takes 2%~3% in 50 a.Now that offshore platforms may cause server subsequent risk, it is safe to take 1% in 30 a as its deformation design level. On the basis of the above analyses and social economic level and the consistency with present codes,the strength design level and deformation design level of Chinese offshore platforms is suggested to take 200 a and 3 000 a respectively.

  20. Relation of ice conditions to climate change in the Bohai Sea of China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The ice conditions in the Bohai Sea and the northern Huanghai Sea greatly change from year to year with winter climate. Ice only covers below 15% of the the waters during the warmest win ter, while it covers more than 80% during the coldest winter. Ice observation and data acquisition are outlined in the paper. The ice-covered area, the position of ice edge and the ice grades give indication of the ice conditions. The local climate of the waters can be expressed by using the air temperature of the stations of Dalian and Yingkou. The variation of the ice condition indexes with the monthly mean air temperature at Dalian from 1952 to 2000 is shown, as well. The local climate and ice conditions in the waters are affected by many factors, such as, evolution of the general atmospheric circulation and the solar activity. The delayed correlation between the ice conditions and lots of the affecting factors is analysed in the paper. The ice conditions are continuously mild since the 1990s, that is relative to the tendency of the global warming. The ice condition variation of the Bohai Sea is related to the El Nino event and the sunspot period. The seasonal evolution of the ice conditions is also described in the paper.

  1. Heat Transfer Coefficient between Ice Cover and Water in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    季顺迎; 岳前进; 毕祥军

    2001-01-01

    The calculative method of heat transfer coefficient between ice cover and water is analyzed considering the heat balance at ice cover bottom firstly. The heat transfer coefficient is calculated with the meteorological, oceanographic data and sea ice conditions measured on the JZ20-2 Oil/Gas Platform in the Bohai Sea during the winter of 1997/1998. From the results, it is shown that the heat transfer coefficient is smaller in the freezing and melting periods, which is about 0.16× 10-3 and 0.04× 10-3 respectively. In the middle of ice season, the heat transfer coefficient has a larger value, which is about 0.5 × 10-3. Lastly, the influences of ice thickness and ice type on the heat transfer coefficient are discussed. With the heat transfer coefficient determined above, the oceanic heat flux in the winter of 1997~1998 is calculated, and its trend in the winter is analyzed. This study can be referenced in the sea ice numerical simulation and prediction in the Bohai Sea.

  2. Effects of Urbanization on Extreme Warmest Night Temperatures During Summer near Bohai

    Institute of Scientific and Technical Information of China (English)

    李庆祥; 黄嘉佑

    2013-01-01

    Many previous studies have focused on the impacts of urbanization on regional mean temperatures. Relatively few have analyzed changes in extreme temperatures. Here, we examine the impact of urbanization on extreme warmest night temperatures from 33 stations in the Bohai area between 1958 and 2009. We compute the Generalized Extreme Value (GEV) distribution of extreme warmest night temperatures and analyze long-term variations in its characteristic parameters. A new classification method based on the factor analysis of changes in extreme night temperatures is developed to detect the effects of urbanization in different cities. Of the three parameters that characterize the GEV distribution, the position parameter is the most representative of long-term changes in extreme warmest night temperatures. During the period of rapid urbanization (i.e., after 1978), all three parameters of the GEV distribution are larger for the urban station group than for the reference station group, so are the magnitudes of their variations, and the urban areas have been experiencing higher extreme warmest night temperatures with larger variability. Different types of cities in the Bohai area have all experienced an urban heat island effect, with an average urbanization effect of approximately 0.3℃per decade.

  3. A model study on carbon cycle and phytoplankton dynamical processes in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    魏皓; 赵亮; 冯士筰

    2003-01-01

    The carbon cycle of lower trophic level in the Bohai Sea is studied with a three-dimension-al biological and physical coupled model. The influences of the processes (including horizontal advection,river nutrient load, active transport etc. ) on the phytoplankton biomass and its evolution are estimated.The Bohai Sea is a weak sink of the CO2 in the atmosphere. During the cycle, 13.7% of the gross pro-duction of the phytoplankton enter the higher trophic level and 76.8 % of it are consumed by the respira-tion itself. The nutrient reproduction comes mainly from the internal biogeochemical loop and the rem-ineralization is an important mechanism of the nutrient transfer from organic form to inorganic. Horizon-tal advection decreases the total biomass and the eutrophication in some sea areas. Change in the nutrientload of a river can only adjust the local system near its estuary. Controlling the input of the nutrient,which limits the alga growth, can be very useful in lessening the phytoplankton biomass.

  4. Investigation of antibiotics in mollusks from coastal waters in the Bohai Sea of China

    International Nuclear Information System (INIS)

    This study focused on the presence and distribution of 22 antibiotics, including eight quinolones, nine sulfonamides and five macrolides in mollusks from the Bohai Sea of China. 190 samples of eleven species were collected in 2006, 2007 and 2009. Laboratory analyses revealed that antibiotics were widely distributed in the mollusks with quinolones as the major compounds with concentrations of 0.71∼1575.10 μg/kg, which were up to two orders of magnitude higher than those of sulfonamides (0∼76.75 μg/kg) and macrolides (0∼36.21 μg/kg). The contents of quinolones and macrolides did not show significant changes from 2006, 2007 to 2009, while sulfonamides decreased significantly from 2006 to 2009. Compared with other sites, the city of Dalian was more polluted with quinolones, while Beidaihe was more contaminated with erythromycin and sulfapyridine. In addition, Mactra veneriformis and Meretrix merehjgntrix Linnaeus contained higher concentrations of quinolones and sulfamonomethoxine, while Mytilus edulis had higher levels of erythromycin and sulfapyridine. - Highlights: ► Antibiotics widely existed in the mollusks from the Bohai Sea. ► Quinolones were the major antibiotics in the mollusks. ► The concentrations of sulfonamides decreased from 2006 to 2009. - Antibiotics were widely distributed in the mollusks with quinolones as the major compounds.

  5. Sea ice thickness analyses for the Bohai Sea using MODIS thermal infrared imagery

    Institute of Scientific and Technical Information of China (English)

    ZENG Tao; SHI Lijian; MARKO Makynen; CHENG Bin; ZOU Juhong; ZHANG Zhiping

    2016-01-01

    Level ice thickness distribution pattern in the Bohai Sea in the winter of 2009–2010 was investigated in this paper using MODIS night-time thermal infrared imagery. The cloud cover in the imagery was masked out manually. Level ice thickness was calculated using MODIS ice surface temperature and an ice surface heat balance equation. Weather forcing data was from the European Centre for Medium-Range Weather Forecasts (ECMWF) analyses. The retrieved ice thickness agreed reasonable well within situ observations from two off-shore oil platforms. The overall bias and the root mean square error of the MODIS ice thickness are –1.4 cm and 3.9 cm, respectively. The MODIS results under cold conditions (air temperature < –10°C) also agree with the estimated ice growth from Lebedev and Zubov models. The MODIS ice thickness is sensitive to the changes of the sea ice and air temperature, in particular when the sea ice is relatively thin. It is less sensitive to the wind speed. Our method is feasible for the Bohai Sea operational ice thickness analyses during cold freezing seasons.

  6. Study on sea water intrusion into palaeochannels on south coastal plain of the Laizhou Bay by the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    韩美

    2003-01-01

    The palaeochannel evolution in the study region is divided into four stages by such meth-ods as 14C dating. Sea water intrusion through palaeochannels has been studied as a focal point.Palaeochannds are the main passageways through which the sea water intrudes at a higher speed,through many means and in a changeable dynamic state.

  7. Joint land-sea seismic survey and research on the deep structures of the Bohai Sea areas

    Institute of Scientific and Technical Information of China (English)

    HAO Tianyao; HAN Guozhong; YOU Qingyu; LIU Lihua; LV Chuanchuan; XU Ya; LI Zhiwei; ZHAO Chunlei; ZHENG Yanpeng; LIU Chenguang

    2013-01-01

    This paper presents the survey and research work of two land-sea profiles in the Bohai Sea, China, carried out in 2010-2011, including the seismic sources on land and in the sea, the ocean bottom seismographs (OBS) and their recovery, the coupling of OBS and the environment noise in sea area, the data quality of OBSs, and the result of data analysis. We focused on the investigation of crustal structures revealed by the two NE\\EW-trending joint land-sea profiles. In combination with the Pn-velocity distribution and gravity-magnetic inversion results in the North China Craton, we propose that the undulation of the Moho interface in the Bohai and surrounding areas is not strong, and the lithospheric thinning is mainly caused by the thinning of its mantle part. The research result indicates that obvious lateral variations of Moho depth and seismic velocity appear nearby all the large-scale faults in Bohai Sea, and there is evidence of underplating and reforming of the lower crust by mantle material in the Bohai area. However, geophysical evidence does not appear to support the“mantle plume”or“delamination”model for the North China Craton destruction. The crustal structure of the Bohai Sea revealed“a relatively normal crust and obviously thinned mantle lid”, local velocity anomalies and instability phenomena in the crust. These features may represent a combined effect of North China-Yangtze collision at an early stage and the remote action of Pacific plate subduction at a late stage.

  8. Estuarine, intertidal and subtidal wetland habitat types in Klag Bay, Chichagof Island, Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Six major estuarine intertidal and subtidal wetland habitat types were identified within the inner basin of Klag Bay. These habitat types are mapped in Fig. 3. The...

  9. Aerial photo mosaic of the Tillamook basin, Oregon in 1967

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Tillamook Bay subbasins and Nehalem River basins encompass 1,369 and 2,207 respective square kilometers of northwestern Oregon and drain to the Pacific Ocean....

  10. EFFECT OF SECONDARY EFFLUENTS ON EUTROPHICATION IN LAS VEGAS BAY, LAKE MEAD, NEVADA

    Science.gov (United States)

    The eutrophication potential of Lake Mead, with primary emphasis on Las Vegas Bay, was determined with Selenastrum capricornutum. Nutrient limitation profiles were determined for three sampling stations in Las Vegas Bay and one in Boulder Basin. After heavy metals were chelated w...

  11. Sedimentary history of the eastern Bohai Sea, China since the deglacial and implications for paleo-tidal current

    Science.gov (United States)

    Yao, Zhengquan; Shi, Xuefa

    2016-04-01

    Numerical simulation suggests that the Holocene sediments re-suspension and distribution in the Bohai Sea was mainly controlled by tidal current regime, which was closely related with sea-level change. Study on sediments in the Bohai Sea thus can provide insights into the evolution of tidal-influenced sedimentary environment and its links with sea-level change. Our understanding of this issue remains incomplete, however, owing to the lack of comprehensive study on sediment core with high-resolution proxies to test such inference. In this study, analyses of sedimentary facies, proxies (grain size, total organic carbon and total nitrogen, X-ray fluorescence scanning Sulfur and Chlorine ratio) and accelerator mass spectrometry 14C dates of a sediment core recovered from the eastern Bohai Sea were carried out to clarify the Holocene sedimentary environment, tidal current change and its relation to the sea-level. The results indicate that the eastern Bohai Sea was dominated by fluvial-coastal environment prior to 12400 cal. a BP due to the sea-level lowstand and changed to tidal-influenced environment from 12400 to 6700 cal. a BP following the rapid sea-level rising. Thereafter shelf environment with minor tidal influence dominated the eastern Bohai Sea under the condition of a deceleration of sea-level rise. The significant change at ~6700 cal. a BP both in sedimentary environment and sediment proxies, indicating an environmental transition from strong tidal-influenced to less tidal-influenced setting. With the sea-level rising from the early Holocene to the mid-Holocene, tidal-current was much strong due to the low sea-level stand and became weak after the maximum transgression at ~6700 cal. a BP. These results are consistent with the numerical simulation, which suggested that less strong tidal current were the consequence of the most highstand sea-level since the mid-Holocene. Our study thus provides a sedimentary record to support the interpretation of numerical

  12. Satellite observations and modeling of oil spill trajectories in the Bohai Sea

    DEFF Research Database (Denmark)

    Xu, Qing; Li, Xiaofeng; Wei, Yongliang;

    2013-01-01

    On June 4 and 17, 2011, separate oil spill accidents occurred at two oil platforms in the Bohai Sea, China. The oil spills were subsequently observed on different types of satellite images including SAR (Synthetic Aperture Radar), Chinese HJ-1-B CCD and NASA MODIS. To illustrate the fate of the oil...... spills, we performed two numerical simulations to simulate the trajectories of the oil spills with the GNOME (General NOAA Operational Modeling Environment) model. For the first time, we drive the GNOME with currents obtained from an operational ocean model (NCOM, Navy Coastal Ocean Model) and surface...... winds from operational scatterometer measurements (ASCAT, the Advanced Scatterometer). Both data sets are freely and openly available. The initial oil spill location inputs to the model are based on the detected oil spill locations from the SAR images acquired on June 11 and 14. Three oil slicks...

  13. Study of Panjin Wetlands Along Bohai Coast (Ⅱ): Ecological Water Requirement of Shuangtaizi Estuarine Wetland

    Institute of Scientific and Technical Information of China (English)

    WANG Tieliang; ZHOU Linfei; ZHAO Be; YANG Peiqi

    2009-01-01

    Shuangtaizi estuarine wetland along the Bohai Sea coast, the biggest bulrush wetland in the world, has been listed in The Record of Important International Wetland Conservation District'. Taking the year of 2 000 as an example, the minimum, the most suitable and the maximum ecological water requirement of Shuangtaizi estuarine wetland are calculated in this paper based on both ecological theory and Geological Information System technology. In addition, the remote sensing technique is adopted in the data acquisition process. Moreover, the total water requirement and the unit area water requirement for different wetland types are obtained. The result is very important for water resources planning, ecological conservation and regional agriculture structure ad-justment in Shuangtaizi. Meanwhile, this study can serve as a useful example for calculating the ecological water requirement in other similar estuarine wetlands.

  14. Difficulties and measures of driving super long piles in Bohai Gulf

    Directory of Open Access Journals (Sweden)

    Shuwang Yan

    2015-03-01

    Full Text Available Long piles of the ocean oil platform are usually manufactured as the integration of several segments, which have to be assembled one by one during installation. During pile driving, excessive pore pressure will build up in such a high level that hydraulic fracturing in the soil round the pile may take place, which will cause the soil to consolidate much faster during pile extension period. Consequently, after pile extension, the soil strength will recover to some extent and the driving resistance will increase considerably, which makes restarting driving the pile very difficult and even causes refusal. A finite element (FE analysis procedure is presented for judging the risk of refusal by estimating the blow counts after pile extension, in which the regain of soil strength is considered. A case analysis in Bohai Gulf is performed using the proposed procedure to explain the pile refusal phenomenon.

  15. A Study on Bottom Friction Coefficient in the Bohai, Yellow, and East China Sea

    Directory of Open Access Journals (Sweden)

    Daosheng Wang

    2014-01-01

    Full Text Available The adjoint tidal model based on the theory of inverse problem has been applied to investigate the effect of bottom friction coefficient (BFC on the tidal simulation. Using different schemes of BFC containing the constant, different constant in different subdomain, depth-dependent form, and spatial distribution obtained from data assimilation, the M2 constituent in the Bohai, Yellow, and East China Sea (BYECS is simulated by assimilating TOPEX/Poseidon altimeter data, respectively. The simulated result with spatially varying BFC obtained from data assimilation is better than others. Results and analysis of BFC in BYECS indicate that spatially varying BFC obtained from data assimilation is the best fitted one; meanwhile it could improve the accuracy in the simulation of M2 constituent. Through the analysis of the best fitted one, new empirical formulas of BFC in BYECS are developed with which the commendable simulated results of M2 constituent in BYECS are obtained.

  16. Heavy metals in sea cucumber juveniles from coastal areas of Bohai and Yellow seas, north China.

    Science.gov (United States)

    Jiang, Haifeng; Tang, Shizhan; Qin, Dongli; Chen, Zhongxiang; Wang, Jinlong; Bai, Shuyan; Mou, Zhenbo

    2015-05-01

    The study was undertaken to assess the contents of heavy metals (Cu, Zn, Cr, Pb, Cd, As and Hg) in sea cucumber (Apostichopus japonicus) juveniles from coastal areas of Bohai and Yellow seas in northern China. Sea cucumber juveniles were collected from twenty commercial hatcheries distributed in five coastal cities. The mean concentrations obtained for heavy metals in mg/kg were as follows: Cu (0.179), Zn (2.634), Cr (0.108), Pb (0.065), Cd (0.161), As (0.372), Hg (0.034). All the mean concentrations were below the maximum residual limits set by Chinese legislation, but As in 10 % samples exceeded the safety threshold. Significant differences in contents of Cr, Pb and Hg were found among the five investigated areas. Overall, the heavy metal levels in sea cucumber juveniles were relatively low and more attention should be paid to toxic metals Pb, Cd, As and Hg in future routine monitoring program.

  17. i4OilSpill, an operational marine oil spill forecasting model for Bohai Sea

    Science.gov (United States)

    Yu, Fangjie; Yao, Fuxin; Zhao, Yang; Wang, Guansuo; Chen, Ge

    2016-10-01

    Oil spill models can effectively simulate the trajectories and fate of oil slicks, which is an essential element in contingency planning and effective response strategies prepared for oil spill accidents. However, when applied to offshore areas such as the Bohai Sea, the trajectories and fate of oil slicks would be affected by time-varying factors in a regional scale, which are assumed to be constant in most of the present models. In fact, these factors in offshore regions show much more variation over time than in the deep sea, due to offshore bathymetric and climatic characteristics. In this paper, the challenge of parameterizing these offshore factors is tackled. The remote sensing data of the region are used to analyze the modification of wind-induced drift factors, and a well-suited solution is established in parameter correction mechanism for oil spill models. The novelty of the algorithm is the self-adaptive modification mechanism of the drift factors derived from the remote sensing data for the targeted sea region, in respect to empirical constants in the present models. Considering this situation, a new regional oil spill model (i4OilSpill) for the Bohai Sea is developed, which can simulate oil transformation and fate processes by Eulerian-Lagrangian methodology. The forecasting accuracy of the proposed model is proven by the validation results in the comparison between model simulation and subsequent satellite observations on the Penglai 19-3 oil spill accident. The performance of the model parameter correction mechanism is evaluated by comparing with the real spilled oil position extracted from ASAR images.

  18. Nitrogen forms and decomposition of organic carbon in the southern Bohai Sea core sediments

    Institute of Scientific and Technical Information of China (English)

    宋金明; 马红波; 吕晓霞

    2002-01-01

    Study on form characteristics of nitrogen in marine sediments is the primary method to research its biogeochemical cycling and nitrogen form characteristics in core sediments can reflect the process and results of early diagenesis in a certain degree. In this paper, Sequential extraction process in natural grain size was used for studying the existent forms of nitrogen in five core sediments of the southern Bohai Sea for the first time. Nitrogen was divided into two parts - transferable and fixed based on whether it could be extracted by the reagent. Distributions and early diagenesis of transferable nitrogen forms in the southern Bohai Sea were researched integratedly. Results indicate that IEF- N and OSFN are predominant forms in transferable part in the studied core sediments. Contents of different nitrogen forms vary differently with depth, and have different diagenesis process. Decomposition constant of organic nitrogen (ON) and OC are about 15.51 × 10-3a-1and 4.79 × 10-3a-1 respectively, and the decomposition content of biogenic elements C, N, P, Si has the sequence N>P>C>Si. OC/TN (simplified as C/N in the following) ratio is much lower than OC/ON, which indicates that sediment preserves plenty of inorganic nitrogen (IN) and/or fixed nitrogen, and the decrease of OC/ON ratio with depth is due to ON reservation in sediments. Generally, transferable nitrogen accounts for more proportion of TN in the surface layer than in the deep layer of core sediments, whereas, some stable forms of nitrogen can activate and become transferable under appropriate environment, which induces the proportion of transferable nitrogen in TN in the deep layer to be almost the same as that in the surface layer.

  19. Tampa Bay: Chapter N

    Science.gov (United States)

    Handley, Larry; Spear, Kathryn; Cross, Lindsay; Baumstark, René; Moyer, Ryan; Thatcher, Cindy

    2013-01-01

    Tampa Bay is Florida’s largest open-water estuary and encompasses an area of approximately 1036 km2 (400 mi2) (Burgan and Engle, 2006; TBNEP, 2006). The Bay’s watershed drains 5,698 km2 (2,200 mi2) of land and includes freshwater from the Hillsborough River to the north east, the Alafia and Little Manatee rivers to the east, and the Manatee River to the south (Figure 1). Freshwater inflow also enters the bay from the Lake Tarpon Canal, from small tidal tributaries, and from watershed runoff. Outflow travels from the upper bay segments (Hillsborough Bay and Old Tampa Bay) into Middle and Lower Tampa Bay. Southwestern portions of the water shed flow through Boca Ciega Bay into the Intracoastal Waterway and through the Southwest Channel and Passage Key Inlet into the Gulf of Mexico. The average depth in most of Tampa Bay is only 3.4 m (11 ft); however, 129 km (80 mi) of shipping channels with a maximum depth of 13.1 m (43 ft) have been dredged over time and are regularly maintained. These channels help to support the three ports within the bay, as well as commercial and recreational boat traffic.

  20. A coupled ice-ocean model for the Bohai Sea Ⅰ.Study on model and parameter

    Institute of Scientific and Technical Information of China (English)

    SU Jie; WU Huiding; ZHANG Yunfei; LIU Qinzhen; BAI Shan

    2004-01-01

    According to the earlier international studies on the coupled ice-ocean model and the hydrology, meteorology, and ice features in the Bohai Sea, a coupled ice-ocean model is developed based on the National Marine Environment Forecast Center's (NMEFC) numerical forecasting ice model of the Bohai Sea and the Princeton ocean model (POM).In the coupled model, the transfer of momentum and heat between ocean and ice is two-way, and the change of ice thickness and concentration depends on heat budget not only at the surface and bottom of ice, but also at the surface of open water between ices. The dynamic and thermodynamic coupling process is expatiated emphatically. Some thermodynamic parameters are discussed as well.

  1. Lost lake - restoration of a Carolina bay

    Energy Technology Data Exchange (ETDEWEB)

    Hanlin, H.G.; McLendon, J.P. [Univ. of South Carolina, Aiken, SC (United States). Dept. of Biology and Geology; Wike, L.D. [Univ. of South Carolina, Aiken, SC (United States). Dept. of Biology and Geology]|[Westinghouse Savannah River Co., Aiken, SC (United States). Savannah River Technology Center; Dietsch, B.M. [Univ. of South Carolina, Aiken, SC (United States). Dept. of Biology and Geology]|[Univ. of Georgia, Aiken, SC (United States)

    1994-09-01

    Carolina bays are shallow wetland depressions found only on the Atlantic Coastal Plain. Although these isolated interstream wetlands support many types of communities, they share the common features of having a sandy margin, a fluctuating water level, an elliptical shape, and a northwest to southeast orientation. Lost Lake, an 11.3 hectare Carolina bay, was ditched and drained for agricultural production before establishment of the Savannah River Site in 1950. Later it received overflow from a seepage basin containing a variety of chemicals, primarily solvents and some heavy metals. In 1990 a plan was developed for the restoration of Lost Lake, and restoration activities were complete by mid-1991. Lost Lake is the first known project designed for the restoration and recovery of a Carolina bay. The bay was divided into eight soil treatment zones, allowing four treatments in duplicate. Each of the eight zones was planted with eight species of native wetland plants. Recolonization of the bay by amphibians and reptiles is being evaluated by using drift fences with pitfall traps and coverboard arrays in each of the treatment zones. Additional drift fences in five upland habitats were also established. Hoop turtle traps, funnel minnow traps, and dip nets were utilized for aquatic sampling. The presence of 43 species common to the region has been documented at Lost Lake. More than one-third of these species show evidence of breeding populations being established. Three species found prior to the restoration activity and a number of species common to undisturbed Carolina bays were not encountered. Colonization by additional species is anticipated as the wetland undergoes further succession.

  2. Ecological risk assessment of arsenic and metals in sediments of coastal areas of northern Bohai and Yellow Seas, China

    OpenAIRE

    Luo, Wei; Lu, Yonglong; Wang, Tieyu; Hu, Wenyou; Jiao, Wentao; Naile, Jonathan E.; Khim, Jong Seong; Giesy, John P.

    2010-01-01

    Distributions of arsenic and metals in surface sediments collected from the coastal and estuarine areas of the northern Bohai and Yellow Seas, China, were investigated. An ecological risk assessment of arsenic and metals in the sediments was evaluated by three approaches: the Sediment Quality Guidelines (SQGs) of the United States Environmental Protection Agency (USEPA), the degree of contamination, and two sets of SQGs indices. Sediments from the estuaries of the Wuli and Yalu Rivers contain...

  3. Validation of Atmospheric Water Vapor Derived from Ship-Borne GPS Measurements in the Chinese Bohai Sea

    OpenAIRE

    Shi-Jie Fan; Jian-Fei Zang; Xiu-Ying Peng; Su-Qin Wu; Yan-Xiong Liu; Ke-Fei Zhang

    2016-01-01

    Atmospheric water vapor (AWV) was investigated for the first time in the Chinese Bohai Sea using a Global Positioning System (GPS) receiver aboard a lightweight (300-ton) ship. An experiment was conducted to retrieve the AWV using the state-of-the-art GPS precise point positioning (PPP) technique. The effects of atmospheric weighted mean temperature model and zenith wet delay constraint on GPS AWV estimates were discussed in the PPP estimation system. The GPS-derived precipitable water vapor ...

  4. Matsu Cultural Heritage and Its Conservation in Bohai Rim - Case Study on the Hall of Fujian in Yantai

    Science.gov (United States)

    Yao, S.

    2015-08-01

    Since the Yuan Dynasty, the belief of Matsu had started to spread from the birthplace to the northern coastal areas in China. Matsu worship developed to the pinnacle with the official promotion on account of the government's dependence on grain transported by sea since the mid-Qing Dynasty. A large amount of Matsu temples emerged in coastal cities of Bohai Rim where it still keeps a large number of them until now. It has much relationship between the spread of Matsu culture and the flow of Fujian population. It was one of the main building way that the Matsu temples attached to the local hall of Fujian in Bohai Rim. The Hall of Fujian in Yantai, Which was built with materials taken from Fujian, in the feature of traditional architectural style from QuanZhou, is very different from the local building style of Yantai. This case indicates that maritime culture of the south area had spread and developed in the north areas under the promotion of the population flow and the economic transaction. The essay introduces briefly about the development of Matsu culture in Bohai Rim and takes the case study of the Hall of Fujian in Yantai analyzing its causes and features, and the value as Matsu heritage. Then the paper will discuss the conservation of Matsu culture mere include the tangible and the intangible culture heritage around the origin area, the heritages of the spread area also have the same importance significance. With the evolution of the society, it calls urgent attention and protection of Matsu culture in Bohai Rim.

  5. The spatial-temporal evolution of aerosol optical depth and the analysis of influence factors in Bohai Rim

    International Nuclear Information System (INIS)

    Aerosol Optical Depth (AOD) is an important parameter of aerosol optical properties and it is an important physical parameter quantity to understanding the atmospheric environment. Bohai Rim is one of the three major urban agglomeration regions with rapidly developing economy in China. The study of AOD over this region is important to understand the environment and climate in Bohai Rim. Firstly, aerosol product data from 2000 to 2010, published by NASA, were used to analyze the temporal-spatial evolution of AOD in Bohai Rim with precision evaluation. The results showed that the spatial distribution of AOD had an obvious regional characteristic. The spatial distribution characterized that a much high value existed at urban areas and plain areas. On the contrary, the low value data existed in some mountainous regions which had higher percentages of forest coverage. The AOD values fluctuated somewhat each year in the region, from the minimum annual mean in 2003 to the maximum in 2009. Generally, the highest AOD value was in summer, followed by spring, autumn and winter. In terms of monthly variation, the value of AOD reached its peak in June and the lowest value was in December. This study analyzed the relation between AOD and some influence factors such as land use types, elevation, and distribution of urban agglomeration and so on. These results provide an important basic dataset for climate and environmental research

  6. Speciation and Degrees of Contamination of Metals in Sediments from Upstream and Downstream Reaches along the Catchment of the Southern Bohai Sea, China

    Directory of Open Access Journals (Sweden)

    Li Xu

    2015-07-01

    Full Text Available Environmental processes and biological community structures change along fluvial gradients within coastal river basins; the accumulation and associated risk of metal contamination would also be expected to change from upstream to downstream reaches. Speciation and degrees of contamination of metals in sediments from the upstream and downstream of river catchments of the southern Bohai Sea were investigated. The mean concentrations of Cu, Zn, Cr, Ni, Cd and Pb from upstream reaches were 82.6, 157, 63.6, 26.6, 0.18 and 24.9 mg/kg, respectively. The mean concentrations of Cu, Zn, Cr, Ni, Cd and Pb from downstream reaches were 38.0, 66.0, 38.9, 18.1, 0.16 and 24.0 mg/kg, respectively. Most of the Cu, Zn, Cr, Ni and Pb in sediments from both the upstream and downstream reaches was mainly associated with the residual fraction. However, Cd was preferentially bound to the exchangeable phase. A cluster analysis was used to study the degree of association between sites, and three distinct clusters were identified in both upstream and downstream sediments. A correlation analysis was conducted to determine the extent of association among metals and showed that metals in sediments from the upstream reaches have more affinity than those in the downstream area. Sediment quality guidelines were used to evaluate potential risks. The risks from Zn, Cr and Ni in the upstream reaches were higher than those from downstream reaches; however, the other three metals (Cu, Pb and Cd showed opposite results.

  7. eBay.com

    DEFF Research Database (Denmark)

    Engholm, Ida

    2014-01-01

    Celebrated as one of the leading and most valuable brands in the world, eBay has acquired iconic status on par with century-old brands such as Coca-Cola and Disney. The eBay logo is now synonymous with the world’s leading online auction website, and its design is associated with the company’s...

  8. 渤海大型底栖动物种类组成与群落结构研究%Studies on the species composition and community structure of macrofauna in the Bohai Sea,China

    Institute of Scientific and Technical Information of China (English)

    刘晓收; 范颖; 史书杰; 华尔; 张志南

    2014-01-01

    In this paper,the abundance,biomass,community structure of macrofauna and its relationship with envi-ronmental factors in the Bohai Sea were studied using the samples collected from 23 stations in August 2008.A to-tal of 300 species were identified,among which the major taxa were polychaetes,crustaceans,mollusks and echino-derms.The average abundance of macrofauna was 1 094.7 ind/m2 ,and the average biomass was 11.78 g/m2 .The highest abundance was located in Liaodong Bay,while the lowest was in Bohai Bay.The highest biomass was loca-ted in the middle of the Bohai Sea,while the lowest appeared in Bohai Strait.CLUSTER and MDS analysis based on the abundance data showed that six communities groups could be divided,which were closely related to the types of sediment.The sediment types in this area included clayey silt,sand,sandy silt,silt sand and sand-silt-clay.BIO-ENV analysis showed that the major environmental factors affecting the community macrofaunal structure and dis-tribution were water depth,sediment silt-clay percentage,phaeophorbide and chlorophyll contents.The number of species and average abundance of macrofauna in the area have obviously declined compared with the historical data in 1990s.It is noted that the dominant species showed a miniaturization trend.The traditionally dominant large-sized species,such as heart urchin and bivalves,were replaced by small-sized polychaetes and crustaceans.The present study showed that the Bohai Sea was affected by human activities and suffered various degrees of pollution in recent years,resulting in the changes of macrofauna community structure.%本文利用2008年8月在渤海23个站位采集的样品对大型底栖动物的丰度、生物量、群落结构及其与环境因子的关系进行了研究。共鉴定出大型底栖动物300种,主要类群包括环节动物多毛类、节肢动物甲壳类、软体动物、棘皮动物等。研究海域大型底栖动物的平均丰度为1094.7 ind/m2

  9. Intrusion of the Bay of Bengal water into the Arabian Sea during winter monsoon and associated chemical and biological response

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Narvekar, J.; Kumar, A.; Shaji, C.; Anand, P.; Sabu, P.; Rijomon, G.; Josia, J.; Jayaraj, K.A.; Radhika, A.; Nair, K.K.C.

    Situated in similar latitudes and subjected to similar atmospheric forcing, the tropical basins of the Arabian Sea looses fresh water due to excess evaporation over precipitation while Bay of Bengal receives freshwater via excess rain and river run...

  10. Distribution characteristics of size-fractionated chlorophyll a,primary production and new production in the Laizhou Bay,July 1997

    Institute of Scientific and Technical Information of China (English)

    蔡煜明; 宁修仁; 刘子琳; 刘诚刚

    2002-01-01

    The distributions of chlorophyll a concentration, primary production and new production were observed in the Laizhou Bay of the Bohai Sea in both spring and neap tides during July 1997. The results showed that there were marked features of spatial zonation in the surveyed area, due to the differences between the geographic environment and the hydrological conditions. Chlorophyll a, primary production and new production were all higher in spring tides than that in neap tides in the Laizhou Bay.The highest values of these parameters were encountered in the central regions of the bay. At most stations, chlorophyll a concentrations at the bottom were higher than that at the surface. The results of size-fractionated chlorophyll a and primary production showed that contributions of nano-combining picoplankton (< 20 μm) to total chlorophyll a and primary production were dominant in phytoplankton community biomass and production of the Laizhou Bay. The environmental factors, primary production and new production in the Laizhou Bay are compared with other sea areas.

  11. 黄渤海夏季微藻调查%Investigation of the microalgae inhabiting the summer seawater of Yellow Sea and Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    鹿琳; 杨官品; 朱葆华; 潘克厚

    2015-01-01

    catching, streak plating and serial diluting, alone or in combination. Molecular systematic analysis identified the isolated as 19 species including 9 bacillariophytas, 3 phaeophytas, 3 heterokontaes, 2 chlorophytas, 1 dinophytas and 1 haptophyte. The isolated species were mainly small in size, of them 9 in chlorophyta, phaeophyta, heterokonatae and haptophyte were in pico-size, and 10 in bacillariophyta and dinophyta were in nano-size. Among all isolated strains, those in genera Navicula, Phaeodactylum, Skeletonema, Pavlova and Nannochloropsis were expected to be important for EPA production due to their high EPA content; 7 chlorophytas may serve as the candidates for biodiesel production;and 8 Bicosoecales in heterokontae promised for high biomass production therough fermentation and further environ-mental pollution bioremediation. In spite of the abundance of microalgae in Yellow Sea and Bohai Sea, almost all spe-cies we fixed and identified by morphology were difficult to cultivate. Pseudo-nitzschia sp. and Navicula sp. (in nano-size) were the only two species observed in fixed seawater and survived laboratory culture. Although the algae in micro-size, Coscinodiscus sp., Ceratium fusus and Noctiluca scintillans, accounted for a large portion in fixed samples, they were unable to survive laboratory culture. Technical means need further optimization in order to get as many culti-vable microalgae as possible. We found that distribution of cultivable microalgae is wide in seawaters. Bacillariophytas spread the whole area, and centralized in Laizhou Bay; while the harmful Prorocentrum minimum was collected from Yellow River Estuary where was nutriments rich thus facing the risk of red tide. Chlorophytas and haptophyte were mainly collected from north Yellow Sea, a few chlorophytas also collected around Port of Tongxhan. Most phaeophytas were collected from the coasts of Shandong Peninsula and Liaodong Peninsula. Most heterokontaes were collected from north Yellow Sea. In

  12. Heavy metals in sea cucumber juveniles from coastal areas of Bohai and Yellow seas, north China.

    Science.gov (United States)

    Jiang, Haifeng; Tang, Shizhan; Qin, Dongli; Chen, Zhongxiang; Wang, Jinlong; Bai, Shuyan; Mou, Zhenbo

    2015-05-01

    The study was undertaken to assess the contents of heavy metals (Cu, Zn, Cr, Pb, Cd, As and Hg) in sea cucumber (Apostichopus japonicus) juveniles from coastal areas of Bohai and Yellow seas in northern China. Sea cucumber juveniles were collected from twenty commercial hatcheries distributed in five coastal cities. The mean concentrations obtained for heavy metals in mg/kg were as follows: Cu (0.179), Zn (2.634), Cr (0.108), Pb (0.065), Cd (0.161), As (0.372), Hg (0.034). All the mean concentrations were below the maximum residual limits set by Chinese legislation, but As in 10 % samples exceeded the safety threshold. Significant differences in contents of Cr, Pb and Hg were found among the five investigated areas. Overall, the heavy metal levels in sea cucumber juveniles were relatively low and more attention should be paid to toxic metals Pb, Cd, As and Hg in future routine monitoring program. PMID:25421712

  13. Perfluoroalkyl and polyfluoroalkyl substances in sediments from South Bohai coastal watersheds, China

    International Nuclear Information System (INIS)

    Highlights: • Relatively high concentrations of PFAS, especially PFOA, were found in the Xiaoqing River sediment. • PFOA and PFBS were the dominant PFAS in the sediments from coastal and riverine area, respectively. • Concentrations of PFNA, PFDA and PFHxS in sediment were significantly correlated with concentrations of organic carbon. • Risks posed by PFOA and PFOS to benthic organisms from concentrations of PFAS in sediments were small. - Abstract: This study investigated the concentrations and distribution of Perfluoroalkyl and polyfluoroalkyl substances (PFAS) in sediments of 12 rivers from South Bohai coastal watersheds. The highest concentrations of ΣPFAS (31.920 ng g−1 dw) and PFOA (29.021 ng g−1 dw) were found in sediments from the Xiaoqing River, which was indicative of local point sources in this region. As for other rivers, concentrations of ΣPFAS ranged from 0.218 to 1.583 ng g−1 dw were found in the coastal sediments and from 0.167 to 1.953 ng g−1 dw in the riverine sediments. Predominant PFAS from coastal and riverine areas were PFOA and PFBS, with percentages of 30% and 35%, respectively. Partitioning analysis showed the concentrations of PFNA, PFDA and PFHxS were significantly correlated with organic carbon. The results of a preliminary environmental hazard assessment showed that PFOS posed the highest hazard in the Mi River, while PFOA posed a relative higher hazard in the Xiaoqing River

  14. Sea level change under IPCC-A2 scenario in Bohai, Yellow, and East China Seas

    Directory of Open Access Journals (Sweden)

    Chang-lin CHEN

    2015-10-01

    Full Text Available Because of the environmental and socioeconomic impacts of anthropogenic sea level rise (SLR, it is very important to understand the processes leading to past and present SLRs towards more reliable future SLR projections. A regional ocean general circulation model (ROGCM, with a grid refinement in the Bohai, Yellow, and East China Seas (BYECSs, was set up to project SLR induced by the ocean dynamic change in the 21st century. The model does not consider the contributions from ice sheets and glacier melting. Data of all forcing terms required in the model came from the simulation of the Community Climate System Model version 3.0 (CCSM3 under the International Panel on Climate Change (IPCC-A2 scenario. Simulation results show that at the end of the 21st century, the sea level in the BYECSs will rise about 0.12 to 0.20 m. The SLR in the BYECSs during the 21st century is mainly caused by the ocean mass redistribution due to the ocean dynamic change of the Pacific Ocean, which means that water in the Pacific Ocean tends to move to the continental shelves of the BYECSs, although the local steric sea level change is another factor.

  15. Sea level change under IPCC-A2 scenario in Bohai, Yellow, and East China Seas

    Institute of Scientific and Technical Information of China (English)

    Chang-lin CHEN; Jun-cheng ZUO; Mei-xiang CHEN; Zhi-gang GAO; C-K SHUM

    2014-01-01

    Because of the environmental and socioeconomic impacts of anthropogenic sea level rise (SLR), it is very important to understand the processes leading to past and present SLRs towards more reliable future SLR projections. A regional ocean general circulation model (ROGCM), with a grid refinement in the Bohai, Yellow, and East China Seas (BYECSs), was set up to project SLR induced by the ocean dynamic change in the 21st century. The model does not consider the contributions from ice sheets and glacier melting. Data of all forcing terms required in the model came from the simulation of the Community Climate System Model version 3.0 (CCSM3) under the International Panel on Climate Change (IPCC)-A2 scenario. Simulation results show that at the end of the 21st century, the sea level in the BYECSs will rise about 0.12 to 0.20 m. The SLR in the BYECSs during the 21st century is mainly caused by the ocean mass redistribution due to the ocean dynamic change of the Pacific Ocean, which means that water in the Pacific Ocean tends to move to the continental shelves of the BYECSs, although the local steric sea level change is another factor.

  16. Morphology, phylogenetic position, and ecophysiology of Alexandrium ostenfeldii (Dinophyceae) from the Bohai Sea, China

    Institute of Scientific and Technical Information of China (English)

    Haifeng GU

    2011-01-01

    Alexandrium ostenfeldii is a potentially toxic dinoflagellate that often occurs in coastal areas at high latitudes.Here we report the presence of A.ostenfeldii in the Bohai Sea,China,for the first time.The vegetative cells ofA.ostenfeldii are characterized by a narrow first apical plate and a large ventral pore located on the anterior right side.Partial large subunit sequence comparison revealed that the Chinese strain differs from the Finnish strains at only three positions,and from A.peruvianum of Spain at five positions.Maximum parsimony analysis revealed that A.ostenfeldii from China and Finland and A.peruvianum from Spain grouped together.They were the nearest sister group to a clade with A.ostenfeldii from New Zealand,Europe,and North America.In culture,growth did not occur at temperatures below 9 ℃ and occurred at salinities between 7 and 27 psu.It took 10-20 days for newly formed cysts to mature at 20 ℃.Lower temperature delayed germination,but the germination rate exceeded 90% at temperatures from 12 to 24 ℃.No germination occurred below 9 ℃ after 1 month of incubation.The Chinese strain ofA.ostenfeldii produced neither spirolides nor paralytic shellfish poisoning toxins.

  17. On Study of Sea Fog over the Yellow and Bohai Seas in China

    Science.gov (United States)

    Fu, G.; Gao, S.; Yang, Y.; Xu, X.; Wang, X.; Chen, Y.; Xue, D.; Shen, J.

    2010-07-01

    A ubiquitous feature of the Yellow and Bohai Sea (YBS) in the eastern Asian region is the frequent occurrence of the sea fog in spring and summer season. The pioneer work on sea fog over YBS can be traced back to Prof. Binhua Wang as early as 1940's. He investigated sea fog systematically and published his book Sea Fog in 1985 (by China Ocean Press and Springer-Verlag). Recently, a research group in the Department of Marine Meteorology at Ocean University of China (OUC) continued sea fog research collaborated with Shandong Meteorological Bureau and Qingdao Meteorological Bureau under the financial supports of National Natural Science Foundation of China and China Meteorological Administration. Their researches involved in both observation analyses and high-resolution modeling of sea fog over YBS. In this talk, the brief history of sea fog research in China will be reviewed firstly. Then, a typical heavy sea fog event over YBS occurred in the morning of 11 April 2004 will be documented by using all available observational data and high-resolution Regional Atmospheric Modeling System (RAMS) modeling results. Finally, the applications of a quasi-operational sea fog forecasting system which was mainly based on RAMS model will be introduced.

  18. Holocene coastal morphologies and shoreline reconstruction for the southwestern coast of the Bohai Sea, China

    Science.gov (United States)

    Liu, Yanxia; Huang, Haijun; Qi, Yali; Liu, Xiao; Yang, Xiguang

    2016-09-01

    Ground-penetrating radar (GPR) reflection profiles were interpreted and combined with sedimentological data to highlight the morpho-evolutionary history of the southwestern sector of the Bohai Sea. The internal structures in GPR images obtained near the Holocene maximum transgression boundary revealed concave-upward and onlap types of transgressive paleo-topography. The relationship between historical courses of the Yellow River and the distribution of shell ridges at three periods (6 ka, 2 ka, and recent times) showed that the concave-upward types derived from the marine sediments overlap the fluvial sediments, and the onlap types from the marine sediments cover the coastal lagoon sediments. Based on the above paleo-geographical setting, previous sea-level markers were corrected, taking into account uncertainties of their relationship to former water levels. The rates of vertical tectonic displacement, evaluated through comparison of the relative sea level (RSL) data from the GPR images and the Holocene predicted sea-level elevation, markedly affected RSL changes. The fitted RSL curves from the corrected sea-level indicators showed that the accuracy of former sea-level determinations can be improved by comparing with the maximum transgressive position of GPR detection. A topographic digital elevation model (DEM) for 6 ka is reconstructed based on the corrected data.

  19. Temporal-spatial variations and developing trends of Chlorophyll-a in the Bohai Sea, China

    Science.gov (United States)

    Fu, Yanzhao; Xu, Shiguo; Liu, Jianwei

    2016-05-01

    The patterns of sea surface Chlorophyll-a (Chl-a) have regional and dynamic features. An understanding of the Chl-a dynamics and whether its trends in the past will be persistent in the future is important for restoration of ecosystem. Spatial and temporal variations of sea surface Chl-a concentrations in the Bohai Sea were investigated with data remotely sensed by MODIS from 2003 to 2014. The goals of this research are to identify the phytoplankton dynamics and detect their correlation with environmental changes and anthropogenic activities. Based on an indicator system built with Mann-Kendall Test and Hurst Exponent, our research shows that the Chl-a concentration in the surface layer is heterogeneous in both temporal and spatial scale. It is higher in costal zones, particularly near the Qinhuangdao coast. The occurrence of spring and summer blooms has a one-month time lag from south to north. An increasing trend that was persistent is evident offshore and a decreasing trend that was persistent is seen near the coast, which may indicate an expansion of eutrophication from coast to deep sea. The seasonality of the phytoplankton bloom is basically driven by vertical structure of water column. Climate and mariculture activity are significant correlated with the Chl-a trends. River discharge and suspended sediment also influence Chl-a.

  20. Hammond Bay Biological Station

    Data.gov (United States)

    Federal Laboratory Consortium — Hammond Bay Biological Station (HBBS), located near Millersburg, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). HBBS was established by...

  1. Humboldt Bay Orthoimages

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of 0.5-meter pixel resolution, four band orthoimages covering the Humboldt Bay area. An orthoimage is remotely sensed image data in which...

  2. Bathymetry in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 4x4 meter resolution bathymetric surface for Jobos Bay, Puerto Rico (in NAD83 UTM 19 North). The depth values are in meters referenced to...

  3. Logy Bay Fishing Settlement

    OpenAIRE

    S H Parsons and Sons

    2003-01-01

    202 x 151 mm. Showing the small inlet with moored rowing boats and rough wooden shacks built on the cliffside. Lying about seven miles from St. John's, Logy Bay was used as a summertime fishing station.

  4. Biscayne Bay Alongshore Epifauna

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Field studies to characterize the alongshore epifauna (shrimp, crabs, echinoderms, and small fishes) along the western shore of southern Biscayne Bay were started...

  5. Study on the Coastal Defense Of Bohai Rim Area in Yongle Period of the Ming Dynasty%明永乐时期环渤海地区的海防*①

    Institute of Scientific and Technical Information of China (English)

    赵树国

    2014-01-01

    明朝建国前后,倭寇大举入侵中国沿海,环渤海地区成为重灾区,直到永乐时期仍很严重。朱棣迁都北京后,环渤海地区海防地位凸显。为加强京畿海防,他采取各种措施,如敦促地方将士积极防御,派遣舟师巡海,命令海运将士剿倭等,取得了一系列胜利,尤以望海埚一战影响最大。与此同时,他还在洪武海防建设的基础上,完善海防机构、设施,在渤海内部、地近京畿地区陆续添设了诸多卫所,并设置了海防营和备倭都司、备倭总兵官等,初步建立起区域协同作战体制,对后世海防建设产生了深远影响。%Before and after the founding of the Ming Dynasty,Japanese pirates had made massive invasion into the coastal area of China,with the Bohai Rim Area as the worst-hit area till the Yongle period. And as the status of coastal defense of the Bohai Rim Area was the more highlighted after Zhu Di,Emper-or Yongle( reigned 1403 ~1424 ),moved the capital to Beijing,he adopted a variety of measures to strengthen the coastal defense of the capital city and its environs. For example,he urged local soldiers to actively defend the Area,dispatched naval fleet on sea patrol,and ordered the shipping officers and men to suppress the Japanese pirates. All this did bring about a series of victories,of which the battle at Wang Hai Guo was the most influential. Meanwhile,based upon the coastal defense construction of Emperor Hongwu( reigned 1368~1398 ),he improved the agencies and facilitates;and inside the Bohai Bay and near the area of the capital city and its environs,he set up many a garrisons( Weisuo),coastal defense battalion,anti-Japanese pirates office and title of commander-in-chief one after the other,ushering in an initial cooperative engagement system which bore far-reaching influence upon the sea defense con-struction of the generations to come.

  6. Corpus Christi, Nueces, and Aransas Bays

    Science.gov (United States)

    Handley, Lawrence R.; Spear, Kathryn A.; Eleonor Taylor,; Thatcher, Cindy

    2015-01-01

    Corpus Christi Bay and Nueces Bay comprise the middle estuarine portion of Texas’ Coastal Bend region (Figure 1; Burgan and Engle, 2006). Aransas Bay is part of the upper estuarine portion of the region. These bays make up part of the Coastal Bend Bays and Estuaries Program, one of the many estuarine areas in the U.S. Environmental Protection Agency’s National Estuary Program (Holt, 1998). The Coastal Bend region is sub-humid and sub-tropical. Summers are long, hot, and humid, and winters are short and mild. The landscape around the estuaries is dominated by row crops, pastures, and brushy rangeland (Handley and others, 2007). The Nueces River, along with other smaller rivers and creeks, provides freshwater inflow—along with essential nutrients and sediment— into Nueces Bay, which feeds into Corpus Christi Bay (Holt, 1998). Freshwater inflow into the Aransas Bay comes from Mission River, Aransas River, and Copano Creek. The region is relatively dry otherwise and prone to droughts. Corpus Christi receives an average of 76.2 cm (30 in) of rain annually; evaporation usually exceeds 177.8 cm (70 in) (Holt, 1998; Handley and others, 2007). The San Antonio-Nueces Coastal Basin drains into Aransas Bay. The Nueces River basin covers 43,253 km2 (16,700 miles2 ), from northwest of San Antonio, flowing southeast to where it drains into Nueces and Corpus Christi Bays (Holt, 1998). The Nueces-Rio Grande basin covers approximately 18,648 1 U.S. Geological Survey National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 2 Harte Research Institute for Gulf of Mexico Studies, Texas A&M University - Corpus Christi, 6300 Ocean Drive, Unit 5869, Corpus Christi, Texas 78412 2 km2 (7,200 miles2 ) and flows partially into Corpus Christi Bay (as well as the upper Laguna Madre). The inflow from Nueces River has declined by approximately 20 percent over the past several decades, partly due to construction of lakes and reservoirs, particularly Lake Corpus Christi

  7. Module bay with directed flow

    Science.gov (United States)

    Torczynski, John R.

    2001-02-27

    A module bay requires less cleanroom airflow. A shaped gas inlet passage can allow cleanroom air into the module bay with flow velocity preferentially directed toward contaminant rich portions of a processing module in the module bay. Preferential gas flow direction can more efficiently purge contaminants from appropriate portions of the module bay, allowing a reduced cleanroom air flow rate for contaminant removal. A shelf extending from an air inlet slit in one wall of a module bay can direct air flowing therethrough toward contaminant-rich portions of the module bay, such as a junction between a lid and base of a processing module.

  8. Feeding habits and food composition of half-fin anchovy, Setipinna taty (C et V) in the Bohai Sea

    Science.gov (United States)

    Gu, Hong

    1990-09-01

    Analysis of the contents of 3,479 stomachs of half-fin anchovy (taken monthly from April 1982 to May 1983 from the Bohai Sea) shows that half-fin anchovy is a zooplanktivorous fish; the young fish feeds mainly on Copepoda while the adult fish feeds mainly on Mysidacea and Acetes chinensis; the food composition has a seasonal change, the main food is Mysidacea in spring but Acetes chinensis in summer and fall; the feeding intensity is closely related to its spawning.

  9. Study of Panjin Wetlands Along Bohai Coast: (Ⅰ) the Information System of Wetlands Based on 3S Technique

    Institute of Scientific and Technical Information of China (English)

    WANG Tieliang; ZHOU Linfei; YANG Peiqi; ZHAO Bo

    2008-01-01

    Based on previous studies on Panjin wetlands along the coast of the Bohai Sea,this paper adopts RS,GIS and GPS tech-niques and establishes the information system for Panjin wetlands.The system involves many functions,such as identification andclassification of wetlands,calculation of the area of wetlands and storage of the information of the wetland management.Moreover,our study indicates that remote sensing technique is a useful tool for great macrography,speediness and accuracy to carry out theextraction,analysis,management and handling of information together with geography information system,which has prospectiveapplications in similar kinds of research.

  10. Two new species of the genus Dorylaimopsis Ditlevsen, 1918 (Nematoda: Adenophora, Comesomatidae) from the Bohai Sea, China

    Science.gov (United States)

    Zhinan, Zhang

    1992-03-01

    Two nematode species of the genus Dorylaimopsis (Family Comesometidae) from the Bohai Sea are described. Dorylaimopsis rabalaisi n. sp. similar to D. punctata Ditlevsen, 1918 from which it can be separated by the small size, short and simple spicules without ventral apophyses or joint line. Dorylaimopsis turneri n. sp. differs from the closest species Dorylaimopsis angelae (Inglis, 1967) by its higher values of de Man ratio ‘a’, much shorter spicules and higher ratio of gubernacular to spicules length. A key to species of the genus based on the key by Jensen (1979) is given.

  11. A Semi-Analytical Model for Remote Sensing Retrieval of Suspended Sediment Concentration in the Gulf of Bohai, China

    OpenAIRE

    Jin-Ling Kong; Xiao-Ming Sun; David W. Wong; Yan Chen; Jing Yang; Ying Yan; Li-Xia Wang

    2015-01-01

    Suspended sediment concentration (SSC) is one of the most critical parameters in ocean ecological environment evaluation and it can be determined using ocean color remote sensing (RS). The purpose of this study is to develop a model that provides a reliable and sensitive evaluation of SSC retrieval using RS data. Data were acquired for and gathered from the Gulf of Bohai where SSC levels are relatively low with an average value below 30 mg·L−1. The study indicates that the most sensitive ban...

  12. 33 CFR 100.124 - Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York.

    Science.gov (United States)

    2010-07-01

    ... South Bay Cross Bay Swim, Great South Bay, New York. 100.124 Section 100.124 Navigation and Navigable... NAVIGABLE WATERS § 100.124 Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York... swimmer or safety craft on the swim event race course bounded by the following points: Starting Point...

  13. Effect of secondary effluents on eutrophication in Las Vegas Bay, Lake Mead, Nevada

    Energy Technology Data Exchange (ETDEWEB)

    Greene, J.C.; Miller, W.E.; Merwin, E.

    1986-01-01

    The eutrophication potential of Lake Mead, with primary emphasis on Las Vegas Bay, was determined with Selenastrum capricornutum. Nutrient limitation profiles were determined for three sampling stations in Las Vegas Bay and one in Boulder Basin. After heavy metals were chelated with EDTA, P was identified as the primary limiting nutrient with N the secondary limiting nutrient for S. capricornutum. Productivity potential was highest in upper Las Vegas Bay near the sewage inflow. Toward the mouth of the bay and in Boulder Basin, progressively lower potentials were defined. Productivity potential could not be predicted from the filtered samples because the nutrients bound up in the indigenous biomass remained on the filters. Autoclaving followed by filtration prior to assay enabled S. capricornutum to produce yields relative to the productivity observed in the lake.

  14. Aerial photo mosaic of the Tillamook and Trask Rivers, Tillamook basin, Oregon in 1939

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Tillamook Bay subbasins and Nehalem River basins encompass 1,369 and 2,207 respective square kilometers of northwestern Oregon and drain to the Pacific Ocean....

  15. Aerial photo mosaic of the Miami River, Tillamook basin, Oregon in 1939

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Tillamook Bay subbasins and Nehalem River basins encompass 1,369 and 2,207 respective square kilometers of northwestern Oregon and drain to the Pacific Ocean....

  16. Aerial photo mosaic of the Wilson and Kilchis Rivers, Tillamook basin, Oregon in 1939

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Tillamook Bay subbasins and Nehalem River basins encompass 1,369 and 2,207 respective square kilometers of northwestern Oregon and drain to the Pacific Ocean....

  17. SEAWATER INTRUSION TYPES AND REGIONAL DIVISIONS IN THE SOUTHERN COAST OF LAIZHOU BAY

    Institute of Scientific and Technical Information of China (English)

    孟广兰; 韩有松; 王少青; 王珍岩

    2002-01-01

    The southern coast of Laizhou Bay, Bohai Sea, is one of the areas in China most seriously impacted by seawater intrusion. Based on the sources of intruding waterbedies, seawater intrusion can be divided into two types: intrusion of saline water derived from modern seawater, and intrusion of subsurface brine and saline water derived from paleo-seawater in shallow Quaternary sediments. There are some distinct differences in their formation, mechanism and damage. The subsurface brine intrusion is a special type, which can cause very serious disaster. The coastal landform and the Quaternary hydrogeological environment are predominant factors in the classification of seawater intrusion types. Various coastal environments in different coastal sections result in three types of intrusion: seawater intrusion, saline groundwater intrusion, and mixed seawater and saline water intrusion, in the southern coast of Laizhou Bay, which can be divided into four areas: the sea-water intrusion area in the northern Laizhou City coast, the mixed seawater and saline groundwater intrusion area in the Baisha River-Jiaolai River mouth plain area, the mixed seawater and saline groundwater intrusion area in the Weihe River mouth plain area northern Changyi county coast, and the saline ground-water intrusion area in the northern Shouguang plains.

  18. SEAWATER INTRUSION TYPES AND REGIONAL DIVISIONS IN THE SOUTHERN COAST OF LAIZHOU BAY

    Institute of Scientific and Technical Information of China (English)

    孟广兰; 韩有松; 王少青; 王珍岩

    2002-01-01

    The southern coast of Laizhou Bay, Bohai Sea, is one of the areas in China most seriously impacted by seawater intrusion. Based on the sources of intruding wate rbodies, seawater intrusion can be divided into two types: intrusion of saline water derived from modern seawater, and intrusion of subsurface brine and saline water derived from paleo-seawater in shallow Quaternary sediments. There are so me distinct differences in their formation, mechanism and damage. The subsurface brine intrusion is a special typ e, which can cause very serious disaster.The coastal landform and the Quaternary hydrogeological environment are pr edominant factors in the classification of seawater intrusion types. Various coastal environments in diff erent coastal sections result in three types of intrusion: seawater intrusion, saline groundwater intrusion, and mixed seawater and saline water intrusion, in the southern coast of Laizhou Bay, which can be divided into four areas: the seawater intrusion area in the northern Laizhou City coast, the mixed seawater and saline groundwater in trusion area in the Baisha River-Jiaolai River mouth plain area, the mixed seawater and saline groundwater intrus ion area in the Weihe River mouth plain area northern Changyi county coast, and the saline groundwater intrusion area in the northern Shouguang plains.

  19. Effects of Tamarisk shrub on physicochemical properties of soil in coastal wetland of the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    HE Xiuping; WANG Baodong; XIE Linping; XIN Ming; WANG Wei; WANG Zicheng; ZHANG Wenquan; WEI Qinsheng

    2016-01-01

    There are many different and even controversial results concerning the effects of Tamarisk on the physicochemical properties of soil. A year-round monitoring of soil salinity, pH and moisture is conducted beneath the Tamarisk shrub in a coastal wetland in the Bohai Sea in China, to ascertain the effects of Tamarisk on the physicochemical properties of soil in coastal wetland. Compared with the control area, the soil moisture content is lower around the area of the taproot when there is less precipitation in the growing season because of water consumption by Tamarisk shrub. However, the soil moisture content is higher around the taproot when there is more precipitation in the growing season or in the non-growing period because of water conservation by the rhizosphere. The absorption of salt by the Tamarisk shrub reduces the soil salinity temporarily, but eventually salt returns to the soil by the leaching of salt on leaves by rainfall or by fallen leaves. The annual average soil moisture content beneath the Tamarisk shrub is lower than the control area by only 6.4%, indicating that the Tamarisk shrub has little effect on drought or water conservation in soils in the temperate coastal wetland with moderate annual precipitation. The annual average salinity beneath the Tamarisk shrub is 18% greater than that of the control area, indicating that Tamarisk does have an effect of rising soil salinity around Tamarisk shrubs. The soil pH value is as low as 7.3 in summer and as high as 10.2 in winter. The pH of soil near the taproot of the Tamarisk shrubs is one pH unit lower than that in the control area during the growing season. The difference in pH is less different from the control area in the non-growing season, indicating that the Tamarisk shrub does have the effect of reducing the alkalinity of soil in coastal wetland.

  20. The Suspended Sediment Concentration Distribution in the Bohai Sea, Yellow Sea and East China Sea

    Institute of Scientific and Technical Information of China (English)

    BIAN Changwei; JIANG Wensheng; Richard J.Greatbatch; DING Hui

    2013-01-01

    The distribution of the suspended sediment eoncentration (SSC) in the Bohai Sea,Yellow Sea and East China Sea (BYECS) is studied based on the observed turbidity data and model simulation results.The observed turbidity results show that (i)the highest SSC is found in the coastal areas while in the outer shelf sea areas turbid water is much more difficult to observe,(ii) the surface layer SSC is much lower than the bottom layer SSC and (iii) the winter SSC is higher than the summer SSC.The Regional Ocean Modeling System (ROMS) is used to simulate the SSC distribution in the BYECS.A comparison between the modeled SSC and the observed SSC in the BYECS shows that the modeled SSC can reproduce the principal features of the SSC distribution in the BYECS.The dynamic mechanisms of the sediment erosion and transport processes are studied based on the modeled results.The horizontal distribution of the SSC in the BYECS is mainly determined by the current-wave induced bottom stress and the fine-grain sediment distribution.The current-induced bottom stress is much higher than the wave-induced bottom stress,which means the tidal currents play a more significant role in the sediment resuspension than the wind waves.The vertical mixing strength is studied based on the mixed layer depth and the turbulent kinetic energy distribution in the BYECS.The strong winter time vertical mixing,which is mainly caused by the strong wind stress and surface cooling,leads to high surface layer SSC in winter.High surface layer SSC in summer is restricted in the coastal areas.

  1. Spring and autumn living coccolithophores in the Bohai Sea and Yellow Sea, China

    Institute of Scientific and Technical Information of China (English)

    JIN Hualong; FENG Yuanyuan; LI Xiaoqian; ZHAI Weidong; SUN Jun

    2015-01-01

    The living coccolithophores (LCs) are an important class of calcified taxa of phytoplankton functional groups, and major producers of marine biogenic inorganic carbon, playing an important role in the marine carbon cycle. In this study, we report the two-demensional abundance, composition of LCs and its correlation with the environmental parameters in spring and autumn, in order to understand the ecological role of LCs in the Yellow Sea and the Bohai Sea. In spring, totally 9 taxa belonging to coccolithophyceae were identified using a polarized microscope at the 1 000× magnification. The dominant species wereEmiliania huxleyi,Gephyrocapsa oceanica, Helicosphaera carteri, andCalcidiscus leptoporus. The abundance of coccosphores and coccoliths ranged 0–7.72 cells/mL, and 0–216.09 coccoliths/mL, with the average values of 0.21 cells/mL, and 11.36 coccoliths/mL, respectively. TheEmiliania huxleyi distribution was similar toGephyrocapsa oceanica. The highest abundance of coccoliths was observed in the east of Shandong Peninsula in northern Yellow Sea, whereasHelicosphaera carteri distributed more widely.Emiliania huxleyi andGephyrocapsa oceanica were the two predominant species in LCs with higher abundances. The distribution of LCs was similar to that of coccoliths. In autumn, 14 taxa belonging to coccolithophyceae were identified with dominant species asEmiliania huxleyi,Gephyrocapsa oceanica, Helicosphaera carteri,Calcidiscus leptoporus andOolithotus fragilis. The abundance of coccosphores and coccoliths ranged 0–24.69 cells/mL, and 0–507.15 coccoliths/mL, with the average values of 1.47 cells/mL, and 55.89 coccoliths/mL, respectively. The highest abundance of coccoliths was located in Qingdao coastal waters and south of the survey area. The distribution of LCs was similar to the coccoliths; in addition, LCs presented large abundance in the east of the central Yellow Sea area.

  2. Bohai People Who Immigrated to Japanese Archipelago and Central Plains Region%移民日本列岛和中原地区的渤海人

    Institute of Scientific and Technical Information of China (English)

    孙炜冉; 董健

    2014-01-01

    关于渤海移民,尤其是亡国后遗民问题,学界基本关注的都是渤海人被迁入辽境、据地建国(定安国、兀惹)及流入王氏高丽和女真地区这三个流向的情况,而少有留意迁入日本列岛和中原地区者。通过史料分析渤海人经过二次移民及战争俘虏等形式移民两地者,藉此,对渤海移民的总体情况做一补阙。%Regarding Bohai immigration, especially the adherents issues after the subjugation, the academic cir-cles focused on three flows directions, namely, the Bohai people were immigrated to Liao Dynasty ter-ritory, occupying the territory to establish a state (Anding State, Wure) and immigrating to the Wang Korea and Jurchen regions, and little attention on the Japanese archipelago and the Central Plains re-gion. So through historical materials to analyze the situation of Bohai people who immigrated to Japanese archipelago and the Central Plains region by means of secondary migration and the war pris-oners, thereby supplementing the research on Bohai immigrants.

  3. The Fermi's Bayes Theorem

    CERN Document Server

    D'Agostini, G

    2005-01-01

    It is curious to learn that Enrico Fermi knew how to base probabilistic inference on Bayes theorem, and that some influential notes on statistics for physicists stem from what the author calls elsewhere, but never in these notes, {\\it the Bayes Theorem of Fermi}. The fact is curious because the large majority of living physicists, educated in the second half of last century -- a kind of middle age in the statistical reasoning -- never heard of Bayes theorem during their studies, though they have been constantly using an intuitive reasoning quite Bayesian in spirit. This paper is based on recollections and notes by Jay Orear and on Gauss' ``Theoria motus corporum coelestium'', being the {\\it Princeps mathematicorum} remembered by Orear as source of Fermi's Bayesian reasoning.

  4. Wind-wave hindcast in the Yellow Sea and the Bohai Sea from the year 1988 to 2002

    Institute of Scientific and Technical Information of China (English)

    HE Hailun; XU Yao

    2016-01-01

    We performed long-term wind-wave hindcast in the Yellow Sea and the Bohai Sea from the year 1988 to 2002, and then analyzed the regional wave climate. Comparisons between model results and satellite data are generally consistent on monthly mean significant wave height. Then we discuss the temporal and spatial characteristics of the climatological monthly mean significant wave heights and mean wave periods. The climatologically spatial patterns are observed as increasing from northwest to southeast and from offshore to deep-water area for both significant wave height and mean wave period, and the patterns are highly related to the wind forcing and local topography. Seasonal variations of wave parameters are also significant. Furthermore, we compute the extreme values of wind and significant wave height using statistical methods. Results reveal the spatial patterns ofN-year return significant wave height in the Yellow Sea and the Bohai Sea, and we discuss the relationship between extreme values of significant wave height and wind forcing.

  5. Analysis of multi-dimensional SAR for determining the thickness of thin sea ice in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xi; ZHANG Jie; MENG Junmin; SU Tengfei

    2013-01-01

    Flat thin ice(30 cm thick) is a common ice type in the Bohai Sea, China. Ice thickness detection is important to offshore exploration and marine transport in winter. Synthetic aperture radar (SAR) can be used to acquire sea ice data in all weather conditions, and it is a useful tool for monitoring sea ice conditions. In this paper, we combine a multi-layered sea ice electromagnetic (EM) scattering model with a sea ice thermodynamic model to assess the determination of the thickness of flat thin ice in the Bohai Sea using SAR at different frequencies, polarization, and incidence angles. Our modeling studies suggest that co-polarization backscattering coefficients and the co-polarized ratio can be used to retrieve the thickness of flat thin ice from C- and X-band SAR, while the co-polarized correlation coefficient can be used to retrieve flat thin ice thickness from L-, C-, and X-band SAR. Importantly, small or moderate incidence angles should be chosen to avoid the effect of speckle noise.

  6. Validation of Atmospheric Water Vapor Derived from Ship-Borne GPS Measurements in the Chinese Bohai Sea

    Directory of Open Access Journals (Sweden)

    Shi-Jie Fan

    2016-04-01

    Full Text Available Atmospheric water vapor (AWV was investigated for the first time in the Chinese Bohai Sea using a Global Positioning System (GPS receiver aboard a lightweight (300-ton ship. An experiment was conducted to retrieve the AWV using the state-of-the-art GPS precise point positioning (PPP technique. The effects of atmospheric weighted mean temperature model and zenith wet delay constraint on GPS AWV estimates were discussed in the PPP estimation system. The GPS-derived precipitable water vapor (PWV and slant-path water vapor (SWV were assessed by comparing with those derived from the Fifth Generation NCAR/Penn State Mesoscale Model (MM5. The results showed the PWV and SWV differences between those derived from both GPS and MM5 are 1.5 mm root mean square (RMS with a bias of 0.2 and 3.9 mm RMS with a bias of -0.7 mm respectively. These good agreements indicate that the GPS-derived AWV in dynamic environments has a comparable accuracy with that of the MM5 model. This suggests that high accuracy and high spatio-temporal resolution humidity fields can be obtained using GPS in the Chinese Bohai Sea, which offers significant potential for meteorological applications and climate studies in this region.

  7. A Semi-Analytical Model for Remote Sensing Retrieval of Suspended Sediment Concentration in the Gulf of Bohai, China

    Directory of Open Access Journals (Sweden)

    Jin-Ling Kong

    2015-04-01

    Full Text Available Suspended sediment concentration (SSC is one of the most critical parameters in ocean ecological environment evaluation and it can be determined using ocean color remote sensing (RS. The purpose of this study is to develop a model that provides a reliable and sensitive evaluation of SSC retrieval using RS data. Data were acquired for and gathered from the Gulf of Bohai where SSC levels are relatively low with an average value below 30 mg·L−1. The study indicates that the most sensitive band to SSC levels in the study area is the NIR band of Landsat5 TM images. A quadratic polynomial semi-analytical model appears to be the best retrieval model based on the relationship between the inherent optical properties (IOPs and apparent optical properties (AOPs of water as described by the quasi-analytical algorithm (QAA. The model has a higher precision and effectiveness for SSC retrieval than data-driven statistical models, especially when SSC level is relatively high. The average relative error and the root mean square error (RMSE are 12.32% and 4.53 mg·L−1, respectively, while the correlation coefficient between observed and estimated SSC by the model is 0.95. Using the proposed retrieval model and TM data, SSC levels of the entire study region in the Gulf of Bohai were estimated. These estimates can serve as the baseline for efficient monitoring of the ocean environment in the future.

  8. Forms of phosphorus and silicon in the natural grain size surface sediments of the southern Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    宋金明; 罗延馨; 吕晓霞; 李鹏程

    2003-01-01

    The forms of phosphorus and silicon in the natural grain sizes surface sediments of the southern Bohai Sea were studied. In sediments, the organic matter bound form of phosphorus was the main form of transferable phosphorus and ranged from 0.37 ,μmol/g to 1.57 μmol/g, accounting for 10.7 % of the total phosphorus, others were the carbonate bound form, iron-manganese oxide bound form and ion-exchange able form; the transferable form of phosphorus accounted for 19.2% of the total phosphorus. Silicon' s carbonate bound form was predominant over others among its transferable forms, and content ranged from t. 55 μmol/g to 8.94 μmol/g, accounting for 0.05 % of the total silicon; the total amount of transferable silicon forms accounted for only 0.12% of the total silicon. Therefore, 19.2 % of the total phosphorus and 0.12 % of the total silicon contained in the surface sediments of the southern Bohai Sea could participate in the biogeochemical cycling.

  9. Antibiotics in the offshore waters of the Bohai Sea and the Yellow Sea in China: Occurrence, distribution and ecological risks

    International Nuclear Information System (INIS)

    The ocean is an important sink of land-based pollutants. Previous studies showed that serious antibiotic pollution occurred in the coastal waters, but limited studies focused on their presence in offshore waters. In this study, eleven antibiotics in three different categories were investigated in offshore waters of the Bohai Sea and the Yellow Sea in China. The results indicated that three antibiotics dehydration erythromycin, sulfamethoxazole and trimethoprim occurred throughout the offshore waters at concentrations of 0.10–16.6 ng L−1 and they decreased exponentially from the rivers to the coastal and offshore waters. The other antibiotics all presented very low detection rates (−1). Although the concentrations were very low, risk assessment based on the calculated risk quotients (RQs) showed that sulfamethoxazole, dehydration erythromycin and clarithromycin at most of sampling sites posed medium or low ecological risks (0.01 −1. ► Their concentrations decreased exponentially from the rivers to the offshore waters. ► Some antibiotics in the offshore water posed medium or low risks to some organisms. -- Some antibiotics were ubiquitous in the offshore waters of the Bohai Sea and the Yellow Sea in China and posed medium or low ecological risks to some sensitive organisms

  10. Yaquina Bay Topobathy DEM

    Science.gov (United States)

    The U.S.EPA contracted with the U.S.ACE to obtain intertidal and subtidal bathymetric soundings of Yaquina Bay between Poole Slough and the South Beach Marina in 2002. These data were compiled with U.S.ACE subtidal soundings from 1999, 1998, 2000 and National Ocean Service soundi...

  11. 渤海浮游植物群落结构及与环境因子的相关性分析%Phytoplankton community in the Bohai Sea and its relationship with environmental factors

    Institute of Scientific and Technical Information of China (English)

    郭术津; 李彦翘; 张翠霞; 翟惟东; 黄韬; 王丽芳; 马威; 谨华龙; 孙军

    2014-01-01

    mainly composed of Bacillariophyta and Dinophyta,and there were also a few species belonging to Chrysophyta. Most of the ecotypes of phytoplankton species were neritic,and preponderant species were Paralia sulcata (Ehrenberg) Cleve, Coscinodiscus excentricus Ehrenberg, Ceratium fusus(Ehrenberg)Dujardin,Pleurosigma affine Grunow, Coscinodiscus asteromphalus Ehrenberg and Nitzschia sp., etc. Cell abundance ranged from 0.89í103 to 16.4í103 cells/L with an average of 4.36í103 cells/L. Horizontally, the surface distribution of cell abundance in the survey area was dominated by diatoms, and the high value appeared in the areas to the south of the Liaodong Bay and to the west of the Bohai Strait. The high cell abundance of dinoflagellates mainly appeared in western and northwestern part of the survey area. In the vertical direction, phytoplankton cell abundance increased in the upper water, and then decreased in the bottom water. Both of Shannon-wiener diversity index and Pielou’s evenness index were higher in the central part of the survey area. By comparing the results with historical data, it can be inferred that the shift phytoplankton community of from diatom dominated community to diatom-dinoflagellate dominated community occurred in central Bohai Sea during the last 30 years. PCA and CCA analysis revealed that the change of nutrient structure in central Bohai Sea might be responsible for this community shift.

  12. Bayes and the Law

    Science.gov (United States)

    Fenton, Norman; Neil, Martin; Berger, Daniel

    2016-01-01

    Although the last forty years has seen considerable growth in the use of statistics in legal proceedings, it is primarily classical statistical methods rather than Bayesian methods that have been used. Yet the Bayesian approach avoids many of the problems of classical statistics and is also well suited to a broader range of problems. This paper reviews the potential and actual use of Bayes in the law and explains the main reasons for its lack of impact on legal practice. These include misconceptions by the legal community about Bayes’ theorem, over-reliance on the use of the likelihood ratio and the lack of adoption of modern computational methods. We argue that Bayesian Networks (BNs), which automatically produce the necessary Bayesian calculations, provide an opportunity to address most concerns about using Bayes in the law. PMID:27398389

  13. NUMERICAL STUDY OF THE INFLUENCE OF WAVES AND TIDE-SURGE INTERACTION ON TIDE-SURGES IN THE BOHAI SEA

    Institute of Scientific and Technical Information of China (English)

    尹宝树; 侯一筠; 程明华; 苏京志; 林明祥; 李明悝; M.I.El-Sabh

    2001-01-01

    Abstract The author's combined numerical model consisting of a third generation shallow water wave model and a 3-D tide-surge model with wave-dependent surface wind stress were used to study the influence of waves on fide-surge motion. For the typical weather case, in this study, the magnitude and mechanism of the influence of waves on tide-surges in the Bohai Sea were revealed for the first time. The results showed that although consideration of the wave-dependent surface wind stresses raise slightly the traditional surface wind stress, due to the accumulated effects, the computed results are improved on the whole. Storm level maximum modulation can reach 0.4 m. The results computed by the combined model agreed well with the measured data.

  14. Sedimentary architecture of the Bohai Sea China over the last 1 Ma and implications for sea-level changes

    Science.gov (United States)

    Shi, Xuefa; Yao, Zhengquan; Liu, Qingsong; Larrasoaña, Juan Cruz; Bai, Yazhi; Liu, Yanguang; Liu, Jihua; Cao, Peng; Li, Xiaoyan; Qiao, Shuqing; Wang, Kunshan; Fang, Xisheng; Xu, Taoyu

    2016-10-01

    Sedimentary architecture dominated by transgression-regression cycles in the shallow Bohai shelf region contains information about global sea-level, climate and local tectonics. However, previous studies of transgression-regression cycles in this region at orbital timescales that extend back to the early Pleistocene are sparse, mainly because of the shortage of well-dated long cores. Although transgression-regression sedimentary cycles in the region have been interpreted in terms of local tectonics, sea-level, and climate change, the detailed structure of marine transgressions and their significance for Quaternary global sea-level variations remains to be examined. In this study, we present an integrated sedimentological, geochemical and paleontological study of a 212.4 m (∼1 Ma) core (BH08) recovered from the Bohai Sea, China, for which an astronomically-based age model is available. Correspondence between marine-terrestrial sedimentary cycles and global sea-level fluctuations suggests that stacking of marine and terrestrial sediments was driven mainly by glacio-eustatic sea-level fluctuations in a context in which tectonic subsidence was largely balanced by sediment supply over the last ∼1 Ma. We report a dominant 100-kyr cycle beginning at ∼650 ka, which reflects the worldwide influence of the mid-Pleistocene transition (MPT) in sea-level records. We find that neritic deposits after the MPT were relatively thicker than before the MPT, which indicates an important control of the MPT on sedimentary architecture through lengthening of the duration of sea-level highstands.

  15. 75 FR 11837 - Chesapeake Bay Watershed Initiative

    Science.gov (United States)

    2010-03-12

    ... Commodity Credit Corporation Chesapeake Bay Watershed Initiative AGENCY: Commodity Credit Corporation and... program funds for the Chesapeake Bay Watershed Initiative. SUMMARY: The Commodity Credit Corporation (CCC... Watershed Initiative for agricultural producers in the Chesapeake Bay watershed in the States of...

  16. BCDC Bay Trail Alignment 2009

    Data.gov (United States)

    California Department of Resources — The Bay Trail provides easily accessible recreational opportunities for outdoor enthusiasts, including hikers, joggers, bicyclists and skaters. It also offers a...

  17. 渤海租赁存在的财务问题分析%Bohai Leasing the Problems of Financial Analysis

    Institute of Scientific and Technical Information of China (English)

    汪萍

    2014-01-01

    文中以渤海租赁有限公司为例,具体介绍了该公司的历史沿革,近几年的经营情况以及介绍了与远东国际租赁有限公司相比渤海租赁所存在的财务中的三大问题。最后,对存在的问题提出对策。%This article to Bohai Leasing co., Ltd as an example, detailed introduces the company's history, the operating situation of recent years and introduces the Bohai Leasing compared with international Far Eastern Leasing Co., LTd. The three major problems in the existing financial. Finally, the existing problems put forward countermeasures.

  18. Study on the Energy Efficiency of Bohai Sea Based on DEA%基于DEA的环渤海能源利用效率研究

    Institute of Scientific and Technical Information of China (English)

    周德田; 马惠

    2014-01-01

    The rapid rise of Bohai economic circle plays a huge role in promoting the national economic development. From the perspective of energy,using the data envelopment analysis,energy utilization efficiency of Bohai Rim area,the Yangtze River Delta region of Shanghai City and Zhejiang Province,the Pearl River Delta region of Guangdong Province from 2000 to 2011 were measured. The results showed that the Bohai Rim area energy efficiency is lower than the Yangtze River Delta and Pearl River Delta. The energy utilization efficiency ranking is as follows:Beijing,Tianjin,Liaoning,Inner Mongolia,Shandong,Hebei,Shanxi. On this basis,strategies to improve the energy efficiency of the Bohai Rim area are proposed .%环渤海经济圈的迅速崛起,对国家经济发展发挥着巨大的推动作用。从能源视角,采用数据包络分析法对环渤海地区、长三角地区的上海市和浙江省、珠三角地区的广东省2000-2011年能源利用效率进行了测度。结果显示,环渤海地区的能源利用效率要低于长三角地区和珠三角地区。目前,环渤海地区四省两市一区的能源利用效率排名依次为:北京、天津、辽宁、内蒙古、山东、河北、山西。在此基础上提出了提高环渤海能源利用效率的对策。

  19. Estimation of submarine groundwater discharge and associated nutrient fluxes in eastern Laizhou Bay, China using 222Rn

    Science.gov (United States)

    Zhang, Yan; Li, Hailong; Wang, Xuejing; Zheng, Chunmiao; Wang, Chaoyue; Xiao, Kai; Wan, Li; Wang, Xusheng; Jiang, Xiaowei; Guo, Huaming

    2016-02-01

    There is increasing evidence that the inputs of nutrients to the Bohai Sea are closely related to submarine groundwater discharge (SGD). In this study, the naturally occurring isotope of radon (222Rn) was used as a tracer to assess SGD in eastern Laizhou Bay. The 222Rn concentration during a tidal period was measured continuously and a mass balance model that included atmospheric loss, tidal effects, mixing loss, diffusion from sediments, and SGD was established. The model budget indicated that 222Rn flux attributed to SGD accounted for 58.3% of the total tracer input to the study area. The time-series of 222Rn revealed that the SGD flux ranged from 6.64 to 7.21 cm d-1, with an average of 6.93 cm d-1, in September 2014. The estimated SGD flux is reasonable compared with those previously estimated in other studies by direct measurement methods, hydrogeological simulation and geochemical tracers. This result, as well as the current understanding of nutrients dissolved in groundwater, confirms the importance of SGD in delivering nutrients to Laizhou Bay and possible impact on marine ecological environment.

  20. Possible origin of the high incidence of Clostridium botulinum type E in an inland bay (Green Bay of Lake Michigan).

    Science.gov (United States)

    Bott, T L; Johnson, J; Foster, E M; Sugiyama, H

    1968-05-01

    Bottom and shoreline sediments of Green Bay, northern Lake Michigan, and rivers of the Green Bay drainage basin, as well as soils of the surrounding land mass, were examined for Clostridium botulinum type E. Detection was based on identification of type E toxin in enrichment cultures and was influenced by many factors. Testing smaller amounts of sample in multiple cultures was more productive than examining large inocula in fewer cultures. Incubation at 30 C was unsatisfactory, but 14 days at 20 C or 7 days at 25 C gave good results. Mild heating (60 C for 30 min) of specimens reduced the incidence of positive findings. Freezing enrichment cultures prior to testing for toxicity eliminated many nonbotulinal toxic substances that killed mice. A control culture inoculated with type E spores was employed to show whether a specimen contained factors which could mask the presence of type E. Samples from 708 stations were tested in 2,446 cultures. Type E was found in nearly all underwater specimens of Green Bay and northern Lake Michigan but was present less frequently in samples taken along their shores. The incidence was still lower in the rivers emptying into Green Bay with the organism being rare on the shores of these rivers and in the soils of the land mass proper. Samples from the upper reaches of the rivers practically never contained type E. Runoff could deposit type E spores in Green Bay, but this is not considered to be the major factor in the high incidence of the organism. Multiplication in the bay itself is indicated. PMID:4870273

  1. Constraints on the sedimentation history of San Francisco Bay from 14C and 10Be

    Science.gov (United States)

    VanGeen, A.; Valette-Silver, N. J.; Luoma, S.N.; Fuller, C.C.; Baskaran, M.; Tera, F.; Klein, J.

    1999-01-01

    Industrialization and urbanization around San Francisco Bay as well as mining and agriculture in the watersheds of the Sacramento and San Joaquin rivers have profoundly modified sedimentation patterns throughout the estuary. We provide some constraints on the onset of these erosional disturbances with 10Be data for three sediment cores: two from Richardson Bay, a small embayment near the mouth of San Francisco Bay, and one from San Pablo Bay, mid-way between the river delta and the mouth. Comparison of pre-disturbance sediment accumulation determined from three 14C-dated mollusk shells in one Richardson Bay core with more recent conditions determined from the distribution of 210Pb and 234Th [Fuller, C.C., van Geen, A., Baskaran, M, Anima, R.J., 1999. Sediment chronology in San Francisco Bay, California, defined by 210Pb, 234Th, 239,240Pu.] shows that the accumulation rate increased by an order of magnitude at this particular site. All three cores from San Francisco Bay show subsurface maxima in 10Be concentrations ranging in magnitude from 170 to 520 x 106 atoms/g. The transient nature of the increased 10Be input suggests that deforestation and agricultural develop- ment caused basin-wide erosion of surface soils enriched in 10Be. probably before the turn of the century.

  2. 渤海湾南堡海域潮流动力地貌特征%TIDAL DYNAMIC GEOMORPHOLOGY IN NANPU AREA OF BOHAI BAY

    Institute of Scientific and Technical Information of China (English)

    白大鹏; 赵铁虎; 李绍全; 周良勇

    2011-01-01

    渤海湾南堡海域的潮流动力地貌特征较为复杂.近几年随着冀东南堡油田的开发,在南堡近岸海域兴建了3个较大的人工岛,研究该海域的潮流动力地貌特征将会对该海区的人工岛建设等工程具有重要意义.利用实测的该海区的潮位、海流、侧扫声纳、底质取样等资料,对南堡油田3个人工岛所处海域的潮流地貌特征进行了研究和分析,推测测区内沙坝的运移特征,研究人工岛建设等对该区的潮流特征的影响.%With the development of the Jidong oilfield,three large artificial islands have been planned in the coastal water around the Nanpu area in recent years. To well understand the character of dynamic geomor-phology of the area is significant for the construction of artificial islands. Using the data of measured tide and related currents offshore, in combination with the data from side-scan sonar and offshore sampling, the authors studied the tidal dynamic geomorphology pattern around the three planned artificial islands, and discussed the possible migration of nearby sand ridges, and its impact on construction of artificial islands. The impact of the construction to the tidal dynamic system is also predicted.

  3. Grain-size based sea-level reconstruction in the south Bohai Sea during the past 135 kyr

    Science.gov (United States)

    Yi, Liang; Chen, Yanping

    2013-04-01

    Future anthropogenic sea-level rise and its impact on coastal regions is an important issue facing human civilizations. Due to the short nature of the instrumental record of sea-level change, development of proxies for sea-level change prior to the advent of instrumental records is essential to reconstruct long-term background sea-level changes on local, regional and global scales. Two of the most widely used approaches for past sea-level changes are: (1) exploitation of dated geomorphologic features such as coastal sands (e.g. Mauz and Hassler, 2000), salt marsh (e.g. Madsen et al., 2007), terraces (e.g. Chappell et al., 1996), and other coastal sediments (e.g. Zong et al., 2003); and (2) sea-level transfer functions based on faunal assemblages such as testate amoebae (e.g. Charman et al., 2002), foraminifera (e.g. Chappell and Shackleton, 1986; Horton, 1997), and diatoms (e.g. Horton et al., 2006). While a variety of methods has been developed to reconstruct palaeo-changes in sea level, many regions, including the Bohai Sea, China, still lack detailed relative sea-level curves extending back to the Pleistocene (Yi et al., 2012). For example, coral terraces are absent in the Bohai Sea, and the poor preservation of faunal assemblages makes development of a transfer function for a relative sea-level reconstruction unfeasible. In contrast, frequent alternations between transgression and regression has presumably imprinted sea-level change on the grain size distribution of Bohai Sea sediments, which varies from medium silt to coarse sand during the late Quaternary (IOCAS, 1985). Advantages of grainsize-based relative sea-level transfer function approaches are that they require smaller sample sizes, allowing for replication, faster measurement and higher spatial or temporal resolution at a fraction of the cost of detail micro-palaeontological analysis (Yi et al., 2012). Here, we employ numerical methods to partition sediment grain size using a combined database of

  4. 75 FR 29891 - Special Local Regulation; Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay...

    Science.gov (United States)

    2010-05-28

    ... Swim, Great South Bay, NY, in the Federal Register (74 FR 32428). We did not receive any comments or... published at 74 FR 32428 on July 8, 2009, is adopted as a final rule with the following changes: PART 100... South Bay Cross Bay Swim, Great South Bay, NY AGENCY: Coast Guard, DHS. ACTION: Final rule. SUMMARY:...

  5. Bayes Multiple Decision Functions

    CERN Document Server

    Wu, Wensong

    2011-01-01

    This paper deals with the problem of simultaneously making many (M) binary decisions based on one realization of a random data matrix X. M is typically large and X will usually have M rows associated with each of the M decisions to make, but for each row the data may be low dimensional. A Bayesian decision-theoretic approach for this problem is implemented with the overall loss function being a cost-weighted linear combination of Type I and Type II loss functions. The class of loss functions considered allows for the use of the false discovery rate (FDR), false nondiscovery rate (FNR), and missed discovery rate (MDR) in assessing the decision. Through this Bayesian paradigm, the Bayes multiple decision function (BMDF) is derived and an efficient algorithm to obtain the optimal Bayes action is described. In contrast to many works in the literature where the rows of the matrix X are assumed to be stochastically independent, we allow in this paper a dependent data structure with the associations obtained through...

  6. Chesapeake Bay impact structure: A blast from the past

    Science.gov (United States)

    Powars, David S.; Edwards, Lucy E.; Gohn, Gregory S.; Horton, Jr., J. Wright

    2015-10-28

    About 35 million years ago, a 2-mile-wide meteorite smashed into Earth in what is now the lower Chesapeake Bay in Virginia. The oceanic impact vaporized, melted, fractured, and displaced rocks and sediments and sent billions of tons of water, sediments, and rocks into the air. Glassy particles of solidified melt rock rained down as far away as Texas and the Caribbean. Large tsunamis affected most of the North Atlantic basin. The resulting impact structure is more than 53 miles wide and has a 23-mile-wide, filled central crater surrounded by collapsed sediments. Now buried by hundreds of feet of younger sediments, the Chesapeake Bay impact structure is among the 20 largest known impact structures on Earth.

  7. 76 FR 38020 - Safety Zone; Bay Point Fireworks, Bay Point Marina; Marblehead, OH

    Science.gov (United States)

    2011-06-29

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Point Fireworks, Bay Point Marina... transit or anchor in a portion of the Lake Erie, Bay Point Marina; Marblehead, OH between 10 p.m. and 10... Zone; Bay Point Fireworks, Bay Point Marina; Marblehead, OH. (a) Location. The following area is...

  8. Source and distribution of sedimentary thallium in the Bohai Sea: Implications for hydrodynamic forces and anthropogenic impact

    Science.gov (United States)

    Hu, Ningjing; Liu, Jihua; Shi, Xuefa

    2015-04-01

    Source and distribution of sedimentary thallium in the Bohai Sea: Implications for hydrodynamic forces and anthropogenic impact Hu Ningjing, Liu Jihua, Shi Xuefa First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, China Thallium (Tl), a non-essential and highly toxic trace metal, is listed as priority toxic pollutant by the United States Environmental Protection Agency (USEPA) (Keith and Telliard, 1979). However, its geochemical cycling in aquatic environment has received far less attention than that of many other trace metals. This has been attributed to relatively little commercial interest in Tl and, until recently, problems inherent in its detection at environmental concentrations (Meeravali and Jiang, 2008). In this study, we investigated the sources, distribution and fate of Tl in surface sediments of the Bohai Sea (BS), China, based on the datasets of total Tl and chemical speciation of Tl of 408 surface sediment samples in the total entire BS. The enrichment factors and chemical speciation of Tl indicated that Tl in BS was dominated by natural Tl, although anthropogenic Tl contamination was observed in the Liuguhe River mouth; the mud deposits are the sinks of Tl and the regional currents and tide systems play a key role on the accumulation of Tl in BS. The distribution of Tl consistent with that of MnO and Fe2O3 as well as the level of Fe-Mn fraction is relatively high, indicating MnO and Fe2O3 influence the geochemical behaviors of Tl in the BS. Although the positive correlation between Tl and TOC is observed for the samples in the BS, however, level of Tl in oxidizable faction could be neglected, suggesting TOC might not be a major factor affecting the concentration of Tl in BS. The low proportion of Tl in the non-residual fraction dominated by the Fe-Mn oxides suggested that the labile Tl was controlled by the Fe-Mn oxides and Tl has a low bioavailability and a minor potential threat to biota in BS. Acknowledgements: this work

  9. Assessment of oil pollution as consequence of the oil leaks from seabed pipeline in the Bohai Sea

    Energy Technology Data Exchange (ETDEWEB)

    Wang, J.; Li, X. [State Key Laboratory of Coastal and Offshore Engineering, Dalian Univ. of Technology, Dalian (China); Goncharov, V.K. [St. Petersburg State Marine Technical Univ., St. Petersburg (Russian Federation); Klementieva, N.Y. [Krylov Shipbuilding Research Institute, St. Petersburg (Russian Federation)

    2005-07-01

    Although oil leaks from pipelines are less dangerous than a blowout of oil as a result of a pipeline break, the presence of oil in the ocean can have a devastating affect on the marine environment, particularly as oil leaks are difficult to detect and can occur over long periods of time. This paper discussed oil pollution in the Bohai Sea. Most of the crude oil in the Bohai oil fields is heavy and contains both paraffin and sand, both of which contribute to greater incidences of cracks and corrosion wormholes in pipes. The Main Points of Model for Assessment of Environmental Consequence of the Oil Leaks from Marine Pipeline (MAECOLMP) is based on the assumption that oil leaks from wormholes on seabed pipelines generate separate oil drops which float up to create a plume in the water. After their emergence on the sea surface, an oil slick forms, which has the shape of a serpentine strip extending along the surface in the direction of the current. The main parameters that define environmental oil pollution are: the dimensions of oil drops in the water; the dimension of the oil slick on the sea surface; and the carryover of crude oil on the coastline. According to the model, the assessment of environmental effects of the oil leaks from the sea bed consist of the following stages: selection of the probable position of wormholes in the pipeline and their size; calculation of the rate of the oil leak from the wormhole for selected sizes and positions; estimation of probable average sizes of oil drops for the selected diameter of wormhole; calculation of boundaries of the plume; calculation of the width and extension of the oil slicks for each selected position of the wormhole; and estimation of the volume of crude oil that can be carried over to the coastline in each case and detection of the most dangerous accident variant. This model permits the use of the Lagrangian description in order to take into account the difference in the velocities of emerging oil drops. It

  10. Bayes multiple decision functions.

    Science.gov (United States)

    Wu, Wensong; Peña, Edsel A

    2013-01-01

    This paper deals with the problem of simultaneously making many (M) binary decisions based on one realization of a random data matrix X. M is typically large and X will usually have M rows associated with each of the M decisions to make, but for each row the data may be low dimensional. Such problems arise in many practical areas such as the biological and medical sciences, where the available dataset is from microarrays or other high-throughput technology and with the goal being to decide which among of many genes are relevant with respect to some phenotype of interest; in the engineering and reliability sciences; in astronomy; in education; and in business. A Bayesian decision-theoretic approach to this problem is implemented with the overall loss function being a cost-weighted linear combination of Type I and Type II loss functions. The class of loss functions considered allows for use of the false discovery rate (FDR), false nondiscovery rate (FNR), and missed discovery rate (MDR) in assessing the quality of decision. Through this Bayesian paradigm, the Bayes multiple decision function (BMDF) is derived and an efficient algorithm to obtain the optimal Bayes action is described. In contrast to many works in the literature where the rows of the matrix X are assumed to be stochastically independent, we allow a dependent data structure with the associations obtained through a class of frailty-induced Archimedean copulas. In particular, non-Gaussian dependent data structure, which is typical with failure-time data, can be entertained. The numerical implementation of the determination of the Bayes optimal action is facilitated through sequential Monte Carlo techniques. The theory developed could also be extended to the problem of multiple hypotheses testing, multiple classification and prediction, and high-dimensional variable selection. The proposed procedure is illustrated for the simple versus simple hypotheses setting and for the composite hypotheses setting

  11. Dose reduction improvements in storage basins of spent nuclear fuel

    International Nuclear Information System (INIS)

    Spent nuclear fuel in storage basins at the Hanford Site has corroded and contaminated basin water, which has leaked into the soil; the fuel also had deposited a layer of radioactive sludge on basin floors. The SNF is to be removed from the basins to protect the nearby Columbia River. Because the radiation level is high, measures have been taken to reduce the background dose rate to as low as reasonably achievable (ALARA) to prevent radiation doses from becoming the limiting factor for removal of the SW in the basins to long-term dry storage. All activities of the SNF Project require application of ALARA principles for the workers. On the basis of these principles dose reduction improvements have been made by first identifying radiological sources. Principal radiological sources in the basin are basin walls, basin water, recirculation piping and equipment. Dose reduction activities focus on cleaning and coating basin walls to permit raising the water level, hydrolasing piping, and placing lead plates. In addition, the transfer bay floor will be refinished to make decontamination easier and reduce worker exposures in the radiation field. The background dose rates in the basin will be estimated before each task commences and after it is completed; these dose reduction data will provide the basis for cost benefit analysis

  12. USGS Tampa Bay Pilot Study

    Science.gov (United States)

    Yates, K.K.; Cronin, T. M.; Crane, M.; Hansen, M.; Nayeghandi, A.; Swarzenski, P.; Edgar, T.; Brooks, G.R.; Suthard, B.; Hine, A.; Locker, S.; Willard, D.A.; Hastings, D.; Flower, B.; Hollander, D.; Larson, R.A.; Smith, K.

    2007-01-01

    Many of the nation's estuaries have been environmentally stressed since the turn of the 20th century and will continue to be impacted in the future. Tampa Bay, one the Gulf of Mexico's largest estuaries, exemplifies the threats that our estuaries face (EPA Report 2001, Tampa Bay Estuary Program-Comprehensive Conservation and Management Plan (TBEP-CCMP)). More than 2 million people live in the Tampa Bay watershed, and the population constitutes to grow. Demand for freshwater resources, conversion of undeveloped areas to resident and industrial uses, increases in storm-water runoff, and increased air pollution from urban and industrial sources are some of the known human activities that impact Tampa Bay. Beginning on 2001, additional anthropogenic modifications began in Tampa Bat including construction of an underwater gas pipeline and a desalinization plant, expansion of existing ports, and increased freshwater withdrawal from three major tributaries to the bay. In January of 2001, the Tampa Bay Estuary Program (TBEP) and its partners identifies a critical need for participation from the U.S. Geological Survey (USGS) in providing multidisciplinary expertise and a regional-scale, integrated science approach to address complex scientific research issue and critical scientific information gaps that are necessary for continued restoration and preservation of Tampa Bay. Tampa Bay stakeholders identified several critical science gaps for which USGS expertise was needed (Yates et al. 2001). These critical science gaps fall under four topical categories (or system components): 1) water and sediment quality, 2) hydrodynamics, 3) geology and geomorphology, and 4) ecosystem structure and function. Scientists and resource managers participating in Tampa Bay studies recognize that it is no longer sufficient to simply examine each of these estuarine system components individually, Rather, the interrelation among system components must be understood to develop conceptual and

  13. Excavation on the Xingnong City-site of the Bohai Period in Hailin City, Heilongjiang%黑龙江海林市兴农渤海时期城址的发掘

    Institute of Scientific and Technical Information of China (English)

    黑龙江省文物考古研究所; 吉林大学考古学系

    2005-01-01

    In 1994 to 1995, Drilling and excavation were carried out at Xingnong in Hailin City,Heilongjiang. The work covered a total area of about 700 sq m and discovered a Bohai period citysiteirregularly square in plan and some 642 m in circumference. Roughly in the middle of the southern city wall, a city gate was found to be distinctly of Tang-style structure. The city walls are built of rammed earth and surrounded by a moat. The cultural remains revealed within the city belong to the Han period of the early Iron Age and to the Bohai period respectively. The city was constructed and existed roughly in middle and late Bohai times. Judging from its location and shape, it must have been a medium- or small-sized plain-style city functioning mainly for the defense of communication lines in the northern Bohal State.

  14. “2012·9·27”环渤海强对流天气监测及成因分析%Monitoring and Genetic Analysis for Severe Convective Weather over Bohai Sea at Sept. 27th 2012

    Institute of Scientific and Technical Information of China (English)

    周艳军; 郭鸿鸣

    2014-01-01

    Using some data and means,such as infrared cloud image of satellite FY-2E,weather radar puzzles,strong convection of NMC monitoring hourly,meteorological data on the island and numerical model products and other information,etc.,the strong convective weather process over Bohai Sea from Apr.27th in 2012,12 to 20(CST)was analyzed.The results showed that the low vortex system southeast moved in the Eastern Inner Mongolia,then it took in Hebei Province,with dry and cold intrusion,and front pocket of warm air and surface cold front overlay .As to the index changing,the value of vertical wind shear(between 0 km and 6 km)was greater than 20m/s at 800 am,the value on K index was 33℃and SI index was-3.8℃,Cape reaches to 1 883 J/kg at 200 pm.these factors resulted to turning out the severe convective weather.At the same time,the monitoring showed the MCS pixels was produced into Beijing and the northern of Hebei at 1200 am,dynamic feature of it on synchronous satellite cloud image and the value of TBB was-65~-25℃,The strength of convective clouds banded was alternating from 3 hours to 6 hours,The strongest periods of severe convective weather in the West Coast of Bohai Sea was during 200 pm to 1700 pm.When it appeared two squall lines,radar echo intensity was greater than 50 dBz.Between them,the temperature of the squall line which impacted Qinhuangdao dropped 10℃in 1 hour,and the pressure dropped 2.7 hPa;The main body of MCS broken after it got into the sea in the 700 pm,and it re-strengthened in the Laizhou Bay and Dalian Peninsula from 800 pm to 900 pm.The West Coast of Bohai Sea met temporary strong wind and hail,and the East Coast met heavy precipitation and the thunder over 8 hours.%利用FY-2E卫星云图、天气雷达拼图、中央台强对流逐小时监测、海岛站及数值模式产品等资料,对2012年9月27日12:00-20:00(CST)出现在环渤海强对流天气过程进行分析。结果表明:位于内蒙东部的低涡系统东移南压,进

  15. Implications of Texture and Erodibility for Sediment Retention in Receiving Basins of Coastal Louisiana Diversions

    Directory of Open Access Journals (Sweden)

    Kehui Xu

    2016-01-01

    Full Text Available Although the Mississippi River deltaic plain has been the subject of abundant research over recent decades, there is a paucity of data concerning field measurement of sediment erodibility in Louisiana estuaries. Two contrasting receiving basins for active diversions were studied: West Bay on the western part of Mississippi River Delta and Big Mar, which is the receiving basin for the Caernarvon freshwater diversion. Push cores and water samples were collected at six stations in West Bay and six stations in Big Mar. The average erodibility of Big Mar sediment was similar to that of Louisiana shelf sediment, but was higher than that of West Bay. Critical shear stress to suspend sediment in both West Bay and Big Mar receiving basins was around 0.2 Pa. A synthesis of 1191 laser grain size data from surficial and down-core sediment reveals that silt (4–63 μm is the largest fraction of retained sediment in receiving basins, larger than the total of sand (>63 μm and clay (<4 μm. It is suggested that preferential delivery of fine grained sediment to more landward and protected receiving basins would enhance mud retention. In addition, small fetch sizes and fragmentation of large receiving basins are favorable for sediment retention.

  16. Back Bay Wilderness area description

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a description of the lands located within the Back Bay National Wildlife Refuge. Within these lands, it designates which area is suitable for...

  17. Annual report, Bristol Bay, 1955

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Commercial fishery management activities for Bristol Bay for 1955, including lists of operators, extensive statistics, descriptions of enforcement activities, and...

  18. FL BAY SPECTROUT-DIET

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Juvenile spotted seatrout and other sportfish are being monitored annually over a 6-mo period in Florida Bay to assess their abundance over time relative to...

  19. Lavaca Bay 1985-1987

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Samples were collected from October 15, 1985 through June 12, 1987 in emergent marsh and non-vegetated habitats throughout the Lavaca Bay system to characterize...

  20. Application of a sea surface temperature front composite algorithm in the Bohai, Yellow, and East China Seas

    Science.gov (United States)

    Ping, Bo; Su, Fenzhen; Meng, Yunshan; Du, Yunyan; Fang, Shenghui

    2016-05-01

    The oceanic front is a narrow zone in which water properties change abruptly within a short distance. The sea surface temperature (SST) front is an important type of oceanic front, which plays a signifi cant role in many fi elds including fi sheries, the military, and industry. Satellite-derived SST images have been used widely for front detection, although these data are susceptible to infl uence by many objective factors such as clouds, which can cause missing data and a reduction in front detection accuracy. However, front detection in a single SST image cannot fully refl ect its temporal variability and therefore, the long-term mean frequency of occurrence of SST fronts and their gradients are often used to analyze the variations of fronts over time. In this paper, an SST front composite algorithm is proposed that exploits the frontal average gradient and frequency more eff ectively. Through experiments based on MODIS Terra and Aqua data, we verifi ed that fronts could be distinguished better by using the proposed algorithm. Additionally through its use, we analyzed the monthly variations of fronts in the Bohai, Yellow, and East China Seas, based on Terra data from 2000 to 2013.

  1. Light beam attenuation and backscattering properties of particles in the Bohai Sea and Yellow Sea with relation to biogeochemical properties

    Science.gov (United States)

    Wang, Shengqiang; Qiu, Zhongfeng; Sun, Deyong; Shen, Xiaojing; Zhang, Hailong

    2016-06-01

    This study reports the first results of the variability in light beam attenuation and the backscattering properties of particles and their controlling factors during the summer in the Bohai Sea (BS) and Yellow Sea (YS), which are two typical shallow and semienclosed seas. We observe large variations in the particulate beam attenuation (cp) and backscattering coefficients (bbp); such variations are mainly attributed to changes in the total suspended matter, while the cross-sectional area concentration shows tighter relationships with both cp and bbp. The mass-specific beam attenuation (cp*) and backscattering coefficients (bbp*) vary more widely over about two orders of magnitude. The attenuation (Qce) and backscattering efficiencies (Qbbe) are important factors that control cp* and bbp*, which clearly separate all the samples into two types. Type 1 samples show low Qce and Qbbe and contain relatively high proportions of organic or large particles, while type 2 samples have high Qce and Qbbe and mainly contain relatively small mineral particles. The majority of the variability in cp* and bbp* within each type is related to the inverse of the product of particle apparent density (ρa) and mean diameter (DA); ρa plays a major role, while DA exerts only a slight impact. Overall, this study provides general knowledge of particulate beam attenuation and the backscattering properties in the BS and YS, which may improve our understanding of underwater radiative transfer processes, marine biogeochemical processes and ocean color algorithms.

  2. Assessment of PCBs and PCDD/Fs along the Chinese Bohai Sea coastline using mollusks as bioindicators.

    Science.gov (United States)

    Zhao, X; Zheng, M; Liang, L; Zhang, Q; Wang, Y; Jiang, G

    2005-08-01

    Mollusk samples such as bivalves and gastropods were collected from eight sampling sites along Bohai Sea coastline from northeastern China. The samples were analyzed for polychlorinated biphenyls (PCBs), polychlorinated dibenzo-p-dioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs) by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC-HRMS) to elucidate bioaccumulation of persistent organic pollutants in benthon. Residue levels of sigmaPCBs and sigmaPCDD/Fs were in the ranges of 66.1 to 583.6 ng/g and 0.9 to 15317 pg/g on a lipid-weight basis, respectively, The pollution source was identified using principal component analysis (PCA) in some coastal areas. It indicated that the typical pollution sources were characterized by PCB3, which was one Chinese technical product of PCBs. PCA also revealed the similarity patterns of PCBs between identical species collected from the different sites. The higher gastropod PCB concentrations were related to a former capacitor factory and the paint factories in some coastal areas, but this was not the case with the bivalves. The results of this study suggest that some gastropod species may be a potential bioindicator or "sentinel" organism for marine PCBs monitoring.

  3. Application of a step-by-step fingerprinting identification method on a spilled oil accident in the Bohai Sea area

    Science.gov (United States)

    Sun, Peiyan; Gao, Zhenhui; Cao, Lixin; Wang, Xinping; Zhou, Qing; Zhao, Yuhui; Li, Guangmei

    2011-03-01

    In recent years, oil spill accidents occur frequently in the marine area of China. Finding out the spilled oil source is a key step in the relevant investigation. In this paper, a step-by-step fingerprinting identification method was used in a spilled oil accident in the Bohai Sea in 2002. Advanced chemical fingerprinting and data interpretation techniques were used to characterize the chemical composition and determine the possible sources of two spilled oil samples. The original gas chromatography -flame ionization detection (GC-FID) chromatogram of saturated hydrocarbons was compared. The gas chromatography-mass spectrometry (GC/MS) chromatograms of aromatic hydrocarbons terpane and sterane, n-alkane and poly-aromatic hydrocarbons (PAHs) were analyzed. The correlation analysis on diagnostic ratios was performed with Student's t-test. It is found that the oil fingerprinting of the spilled oil (designated as sz1) from the polluted sand beach was identical with the suspected oil (designated as ky1) from a nearby crude oil refinery factory. They both showed the fingerprinting character of mixed oil. The oil fingerprinting of the spilled oil (designated as ms1) collected from the port was significantly different from oil ky1 and oil sz1 and was with a lubricating oil fingerprint character. The identification result not only gave support for the spilled oil investigation, but also served as an example for studying spilled oil accidents.

  4. Exchange of polycyclic aromatic hydrocarbons across the air-water interface in the Bohai and Yellow Seas

    Science.gov (United States)

    Chen, Yingjun; Lin, Tian; Tang, Jianhui; Xie, Zhiyong; Tian, Chongguo; Li, Jun; Zhang, Gan

    2016-09-01

    In this study, air and surface seawater samples collected from the Bohai (BS) and Yellow Seas (YS) in May 2012 were determined exchange of PAHs, especially of low-molecular-weight (LMW) PAHs (three- and four-ring PAHs) at the air-water interface. Net volatilization fluxes of LMW PAHs were 266-1454 ng/m2/d and decreased with distance from the coast, indicating that these PAHs transported from coastal runoff were potential contributors to the atmosphere in the BS and YS. Moreover, LMW PAHs were enriched in the dissolved phase compared with those in the particulate phase in the water column, possibly suggesting that the volatilized LMW PAHs were directly derived from wastewater discharge or petroleum pollution rather than released from contaminated sediments. The air-sea exchange fluxes of the three-ring PAHs were 2- to 20-fold higher than their atmospheric deposition fluxes in the BS and YS. The input to and output from the water reached equilibrium for four-ring PAHs. Differently, five- and six-ring PAHs were introduced into the marine environment primarily through dry and wet deposition, indicating that the water column was still a sink of these PAHs from the surrounding atmosphere.

  5. 210Pb and 137Cs measurements in the Circum Bohai Sea coastal region: sedimentation rates and implications

    Institute of Scientific and Technical Information of China (English)

    Fu WANG; Hong WANG; Jianfen LI; Yandong PEI; Changfu FAN; Lizhu TIAN; Zhiwen SHANG; Meiyu SONG; Yan GENG

    2008-01-01

    The representative 210Pb and 137Cs age-depth profiles were selected from more than 100 sites in the Circum Bohai Sea (CBS)coastal region to examine the sedimentation rates and associated environmental changes.There are three unique 210Pbexc distribution patterns:1)ideal-decaying type,representing relatively constant sediment supply and quieter environmental setting;2)wiggling type,but with approximately equivalent amplitude,representing coarser sediments and associated stronger flow current environment;and 3) episodic-eventinfluencing type,each representing typhoon storm-influenced depositional environment.Our results also show that there is a lower sedimentation rate(ca.0.1 cm/a)in the coastal lowlands,a higher sedimentation rate(ca.0.53 cm/a)in the intertidal flat and an intermediate rate of ca.0.58 cm/a in the subtidal zone near the Huanghua Harbor.The interbedded silt layer occurring in the core sediment reveals lower 210Pb activities,indicating a discontinuous sedimentation mostly due to typhoon events which dwarfs against 210Pb and 137Cs applicability.Overall,the 210Pb and 137Cs measurements of the present study provide physical insight into the evaluation of the coastal-marine ecological environment and associated management.

  6. Regional multi-compartment ecological risk assessment: Establishing cadmium pollution risk in the northern Bohai Rim, China.

    Science.gov (United States)

    Shi, Yajuan; Wang, Ruoshi; Lu, Yonglong; Song, Shuai; Johnson, Andrew C; Sweetman, Andrew; Jones, Kevin

    2016-09-01

    Ecological risk assessment (ERA) has been widely applied in characterizing the risk of chemicals to organisms and ecosystems. The paucity of toxicity data on local biota living in the different compartments of an ecosystem and the absence of a suitable methodology for multi-compartment spatial risk assessment at the regional scale has held back this field. The major objective of this study was to develop a methodology to quantify and distinguish the spatial distribution of risk to ecosystems at a regional scale. A framework for regional multi-compartment probabilistic ecological risk assessment (RMPERA) was constructed and corroborated using a bioassay of a local species. The risks from cadmium (Cd) pollution in river water, river sediment, coastal water, coastal surface sediment and soil in northern Bohai Rim were examined. The results indicated that the local organisms in soil, river, coastal water, and coastal sediment were affected by Cd. The greatest impacts from Cd were identified in the Tianjin and Huludao areas. The overall multi-compartment risk was 31.4% in the region. The methodology provides a new approach for regional multi-compartment ecological risk assessment. PMID:27286039

  7. Inversion of two-dimensional tidal open boundary conditions of M2 constituent in the Bohai and Yellow Seas

    Institute of Scientific and Technical Information of China (English)

    CAO Anzhou; GUO Zheng; L(U) Xianqing

    2012-01-01

    Two-dimensional tidal open boundary conditions of the M2 constituent in the Bohai and Yellow Seas(BYS)have been estimated by assimilating T/P altimeter data.During inversion,independent point (IP)strategy was used,in which several IPs on the open boundary is assumed,values at these IPs can be optimized with an adjoint method,and those at other grid points are determined by linearly interpolating the values at IPs.The reasonability and feasibility of the model are tested by ideal twin experiments.In the practical experiment(PE)after assimilation,the cost function may reach 1% or less of its initial value.Mean absolute errors in amplitude and phase can be less than 5 cm and 5°,respectively,and the obtained co-chart can show the character of the M2 constituent in the BYS.The results of the PE indicate that using only two IPs on the open boundary can yield better simulated results.

  8. Application of a Step-by-Step Fingerprinting Identification Method on a Spilled Oil Accident in the Bohai Sea Area

    Institute of Scientific and Technical Information of China (English)

    SUN Peiyan; GAO Zhenhui; CAO Lixin; WANG Xinping; ZHOU Qing; ZHAO Yuhui; LI Guangmei

    2011-01-01

    In recent years, oil spill accidents occur frequently in the marine area of China. Finding out the spilled oil source is a key step in the relevant investigation. In this paper, a step-by-step fingerprinting identification method was used in a spilled oil accident in the Bohai Sea in 2002. Advanced chemical fingerprinting and data interpretation techniques were used to characterize the chemical composition and determine the possible sources of two spilled oil samples. The original gas chromatography -flame ionization detection (GC-FID) chromatogram of saturated hydrocarbons was compared. The gas chromatography-mass spectrometry (GC/MS)chromatograms of aromatic hydrocarbons terpane and sterane, n-alkane and poly-aromatic hydrocarbons (PAHs) were analyzed. The correlation analysis on diagnostic ratios was performed with Student's t-test. It is found that the oil fingerprinting of the spilled oil (designated as szl) from the polluted sand beach was identical with the suspected oil (designated as kyl) from a nearby crude oil refinery factory. They both showed the fingerprinting character of mixed oil. The oil fingerprinting of the spilled oil (designated as msl) collected from the port was significantly different from oil kyl and oil szl and was with a lubricating oil fingerprint character. The identification result not only gave support for the spilled oil investigation, but also served as an example for studying spilled oil accidents.

  9. Exchange of polycyclic aromatic hydrocarbons across the air-water interface in the Bohai and Yellow Seas

    Science.gov (United States)

    Chen, Yingjun; Lin, Tian; Tang, Jianhui; Xie, Zhiyong; Tian, Chongguo; Li, Jun; Zhang, Gan

    2016-09-01

    In this study, air and surface seawater samples collected from the Bohai (BS) and Yellow Seas (YS) in May 2012 were determined exchange of PAHs, especially of low-molecular-weight (LMW) PAHs (three- and four-ring PAHs) at the air-water interface. Net volatilization fluxes of LMW PAHs were 266-1454 ng/m2/d and decreased with distance from the coast, indicating that these PAHs transported from coastal runoff were potential contributors to the atmosphere in the BS and YS. Moreover, LMW PAHs were enriched in the dissolved phase compared with those in the particulate phase in the water column, possibly suggesting that the volatilized LMW PAHs were directly derived from wastewater discharge or petroleum pollution rather than released from contaminated sediments. The air-sea exchange fluxes of the three-ring PAHs were 2- to 20-fold higher than their atmospheric deposition fluxes in the BS and YS. The input to and output from the water reached equilibrium for four-ring PAHs. Differently, five- and six-ring PAHs were introduced into the marine environment primarily through dry and wet deposition, indicating that the water column was still a sink of these PAHs from the surrounding atmosphere.

  10. Mass Deposition Fluxes of Asian Dust to the Bohai Sea and Yellow Sea from Geostationary Satellite MTSAT: A Case Study

    Directory of Open Access Journals (Sweden)

    Qianguang Tu

    2015-11-01

    Full Text Available Windblown dust aerosol plays an important role in marine ecosystems once they are deposited and dissolved. At present, methods for estimating the deposition flux are mainly limited to direct measurements or model outputs. Additionally, satellite remote sensing was often used to estimate the integral dust column concentration (DCC. In this paper, an algorithm is developed to estimate the mass deposition fluxes of Asian dust by satellite. The dust aerosol is identified firstly and then the DCC is derived based on the relationships between the pre-calculated lookup table (LUT and observations from Japanese geostationary Multi-functional Transport Satellites (MTSAT. The LUT is built on the dust cloud and surface parameters by a radiation transfer model Streamer. The average change rate of deposition is derived, which shows an exponential decay dependence on transport time along the pathway. Thus, the deposition flux is acquired via integrating the hourly deposition. This simple algorithm is applied to a dust storm that occurred in the Bohai Sea and Yellow Sea from 1 to 3 March 2008. Results indicate that the properties of the dust cloud over the study area changed rapidly and the mass deposition flux is estimated to be 2.59 Mt.

  11. Sedimentary phosphorus cycling and a phosphorus mass balance for the Green Bay (Lake Michigan) ecosystem

    Science.gov (United States)

    Klump, J.V.; Edgington, D. N.; Sager, P.E.; Robertson, D.M.

    2011-01-01

    The tributaries of Green Bay have long been recognized as major sources of phosphorus in the Lake Michigan basin. The status of Green Bay as a sink or source of phosphorus for Lake Michigan proper has been less well defined. The bay receives nearly 70% of its annual load of phosphorus ( 700 metric tons (t) · year-1) from a single source: the Fox River. Most of this phosphorus is deposited in sediments accumulating at rates that reach 160 mg · cm-2 · year-1 with an average of 20 mg · cm-2 · year-1. The phosphorus content of these sediments varies from 70 µmol · g-1. Deposition is highly focused, with ~70% of the total sediment accumulation and at least 80% of the phosphorus burial occurring within 20% of the surface area of the bay. Diagenetic and stoichiometric models of phosphorus cycling imply that >80% of the phosphorus deposited is permanently buried. External phosphorus loading to the bay is combined with sediment fluxes of phophorus to arrive at a simple phosphorus budget. Green Bay acts as an efficient nutrient trap, with the sediments retaining an estimated 70-90% of the external phosphorus inputs before flowing into Lake Michigan.

  12. Iron and inorganic carbon in Liaodong Gulf sediments of Bohai Sea in China

    Institute of Scientific and Technical Information of China (English)

    NIU Lifeng; LI Xuegang; SONG Jinming; YUAN Huamao; LI Ning; DAI Jicui

    2006-01-01

    Iron in seawater is an essential trace metal for phytoplankton that plays an important role in the marine carbon cycle. But most studies focused on oceanic iron fertilization in high nutrient low chlorophyll (HNLC) seawaters. A study of inorganic carbon (IC) forms and its influencing factors was presented in Liaodong Gulf sediments, and especially the influence of iron was discussed in detail. Inorganic carbon in Liaodong Gulf sediments was divided into five forms: NaCl, NH3·H2O, NaOH, NH2OH·HCl and HCl. The concentration of NaCl and NaOH forms were similar and they only occupied the minority of total inorganic carbon (TIC). However, NH3·H2O, NH2OH·HCl and HCl forms were the principal forms of TIC and accounted for more than 80% of TIC. Especially, the percentage of NH3·H2O form was much higher than that in the Changjiang River Estuary and Jiaozhou Bay sediments. All forms of inorganic carbon were influenced by organic carbon,pore water, iron, pH, redox potential(Eh) and sulfur potential(Es) in sediments, moreover, the influences had different characteristics for different IC forms. However, the redox reactions of iron affected mainly active IC forms. Iron had little effect on NH2OH·HCl and HCl forms of IC which were influenced mainly by pH. Iron had a stronger influence on NaCl, NaOH and NH3·H2O forms of IC; the influence of Fe2+ was higher than Fe3+ and its effect on NH3·H2O form was stronger than on NaCl and NaOH forms.

  13. A Framework for Integrated Management of Transboundary Basins: the case of Sio sub-catchment in East Africa.

    OpenAIRE

    Obando, Joy A.; Makalle, Albinus; Bamutaze, Bamutaze

    2007-01-01

    The Sio sub-catchment is transboundary, originating in Kenya and flowing into Berkeley Bay of the Lake Victoria basin. It forms an important sub-catchment of the Nile basin and a significant base for the livelihood of small scale farmers engaged in mixed farming, depending on agriculture and livestock keeping as well as a large population depending on fishing. Indeed, high population densities exceeding 300 persons per square kilometre and cattle densities of 38 have been noted within basin, ...

  14. Immature Oil Resources in Terrestrial Deposits in China

    Institute of Scientific and Technical Information of China (English)

    Hou Dujie; Wang T.-G

    1997-01-01

    @@ Distribution of Immature Oil in China The early generated oil (so called immature oil) is the liquid hydrocarbons released by the organic matter, which underwent low-temperature biochemical and chemical reactions in the early stage (Ro=0.3%~0.6%). The early generated oil is very widespread in terrestrial deposit in China. There are commercial immature oil from East China such as Bohai Bay Basin, Jianghan Basin, Nanxiang Basin, Subei Basin, etc. to Qaidam Basin, Junggar Basin in West China although the exact amount of immature oil resource is still unknown.

  15. PetroChina Domestic Oil Exploration and Development Fruitful

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ PetroChina, of which CNPC is the parent company,has continued to focus itself on the main businesses of oil and gas exploration and development at home and achieved remarkable results this year in its various oil and gas fields nationwide. With the efforts concentrated on the basin areas, PetroChina has made important progress in exploration of Sichuan Basin, Ordos Basin, Bohai Bay Basin, Junggar Basin and Tarim Basin, maintaining a good impetus in the company's oil and gas reserves growth.

  16. Application of Sediment Trend Analysis in the Examination of Sediment Transport Dynamics of Missisquoi Bay

    Science.gov (United States)

    Kraft, M. P.; Manley, P.; Singer, J.; Manley, T.; McLaren, P.

    2013-12-01

    Missisquoi Bay is located between Vermont and Quebec in the northeast sector of the Restricted Arm of Lake Champlain. The average depth of the Bay is slightly less than 3 meters with a surface area covering 77.5 km2. The Bay receives water from eastern and western catchment basins, most notably via the Missisquoi, Rock, and Pike Rivers. Circulation within Missisquoi Bay has been altered by the construction of railroad causeways in the late 19th century and highway construction in the early 20th century. Over the past several decades there have also been changes in land-use practices, including the intensification of agriculture, increased animal husbandry, and urbanization. As a consequence of construction and changing land use, loadings of nitrogen and phosphorus to the Bay have increased seasonal oxygen depletion causing eutrophication. Since monitoring began in 1992, Missisquoi Bay has displayed the highest mean total phosphorus concentrations and chlorophyll a concentrations in Lake Champlain. Various efforts have taken place to reduce nutrient loading to Missisquoi Bay, but persistent release of phosphorus from bottom sediments will continue to delay for decades the recovery from nutrient diversion. To better understand the causes and timing of eutrophication in Missisquoi Bay, one component of a 5-year integrated VT EPSCoR - RACC program included an examination of N and P loadings and their distribution throughout the Bay. Internal circulation patterns are also being studied. To determine the pattern of net sediment transport and determine sediment behavior (erosion and accretion), a Sediment Trend Analysis (STA) was performed using 369 grab samples collected in the Bay. Grain size distributions for the surface sediment samples were determined using a Malvern Mastersizer 2000 particle size analyzer. Sediment maps showing the proportion of gravel, sand, and mud show that near major river distributaries sand-sized sediment was dominant with muds becoming more

  17. Tsunami Inundation modeling for Tolaga Bay, Tokomaru Bay, Hicks Bay and Te Araroa communities

    Science.gov (United States)

    Barberopoulou, A.; Wang, X.; Power, W. L.

    2012-12-01

    We assess the tsunami hazard to four communities in Raukumara Peninsula (Northeastern region of North Island of New Zealand): Tokomaru Bay, Tolaga Bay, Hicks Bay and Te Araroa. Representative severe but realistic scenarios that could affect the Raukumara peninsula are earthquakes that rupture the interface between the Australian and Pacific plates, earthquakes that rupture faults within the overlying Australian plate or the subducting Pacific plate (location is not always well constrained). Earthquakes that rupture both the plate interface and simultaneously faults within the crust of the Australian plate are also a possibility. Tsunamis may also be caused by submarine landslides that occur near the edge of the continental shelf, but these are not considered here. For this study four scenario events were constructed, including a distant event from South America (offshore Peru), outer rise events and a thrust event in the Hikurangi region off the east coast of New Zealand. The sources are not exhaustive but representative of the types of significant events that could occur in the region and were either improved from earlier sources or derived from recent studies. Available high resolution LiDAR and RTK data were combined with topographic and LINZ data for the development of bathymetric/topographic grids. Our modelling results show that Tolaga Bay appears most vulnerable to tsunami inundation although Hicks Bay and Te Araroa are also significantly inundated in several of the scenarios. Tokomaru Bay is naturally well protected because the rapid change in elevation limits the range of inundation. The worst scenario for Tokomaru Bay was an earthquake in the Hikurangi subduction zone resulting in large flow depths, whereas for Tolaga Bay inundation is severe from most scenarios. Hicks Bay and Te Araroa get the most severe flooding from earthquakes in South America and on the Hikurangi subduction zone. Inundation extent is similar for Tolaga Bay during the Outer Rise and

  18. Water Resources Utilization Efficiency Preliminary Evaluation of Liaoning along Bohai Region%辽宁沿渤海地区水资源利用效率初评

    Institute of Scientific and Technical Information of China (English)

    李川; 王恩德

    2012-01-01

    Summarizes the water resources use efficiency of concept and calculation method,combed the liaoning along bohai region of the key industry,use narrow sense of water use efficiency calculation method,based on iaoning along bohai region water consumption in 2007,Calculate the liaoning along bohai 5 cities water resources utilization efficiency,including water consumption per ten thousand yuan GDP,water consumption per ten thousand yuan value added of industry,water consumption per ten thousand yuan value added of construction,water consumption per ten thousand yuan value added of The third industry,water consumption per capita,water consumption of urban household,water consumption of rural residents.The results show that,water consumption per ten thousand yuan GDP and per capita of Panjin are all the highest in liaoning province along bohai 5 cities,the main reason is agricultural large use water,but agricultural output GDP relatively is less.%总结了水资源利用效率的概念和计算方法,梳理了辽宁沿渤海地区的重点产业,采用狭义的水资源利用效率计算方法,以2007年辽宁沿渤海地区用水量为基础,分别计算了辽宁沿渤海5市的万元GDP用水量、万元工业增加值用水量、万元建筑业增加值用水量、万元三产增加值用水量、人均用水量、城镇居民生活用水量、农村居民用水量。结果表明,盘锦人均用水量和万元GDP用水量在辽宁省沿渤海5市中均为最高,其主要原因是盘锦农业用水多,农业产出的GDP相对少。

  19. Generation and propagation of nonlinear internal waves in Massachusetts Bay

    Science.gov (United States)

    Scotti, A.; Beardsley, R.C.; Butman, B.

    2007-01-01

    During the summer, nonlinear internal waves (NLIWs) are commonly observed propagating in Massachusetts Bay. The topography of the area is unique in the sense that the generation area (over Stellwagen Bank) is only 25 km away from the shoaling area, and thus it represents an excellent natural laboratory to study the life cycle of NLIWs. To assist in the interpretation of the data collected during the 1998 Massachusetts Bay Internal Wave Experiment (MBIWE98), a fully nonlinear and nonhydrostatic model covering the generation/shoaling region was developed, to investigate the response of the system to the range of background and driving conditions observed. Simplified models were also used to elucidate the role of nonlinearity and dispersion in shaping the NLIW field. This paper concentrates on the generation process and the subsequent evolution in the basin. The model was found to reproduce well the range of propagation characteristics observed (arrival time, propagation speed, amplitude), and provided a coherent framework to interpret the observations. Comparison with a fully nonlinear hydrostatic model shows that during the generation and initial evolution of the waves as they move away from Stellwagen Bank, dispersive effects play a negligible role. Thus the problem can be well understood considering the geometry of the characteristics along which the Riemann invariants of the hydrostatic problem propagate. Dispersion plays a role only during the evolution of the undular bore in the middle of Stellwagen Basin. The consequences for modeling NLIWs within hydrostatic models are briefly discussed at the end.

  20. Guide to the littoral zone vascular flora of Carolina bay lakes (U.S.A.)

    Science.gov (United States)

    Howell, Nathan; Braham, Richard R

    2016-01-01

    Abstract Background Carolina bays are elliptic, directionally aligned basins of disputed origin that occur on the Atlantic Coastal Plain from the Delmarva Peninsula to southern Georgia. In southeastern North Carolina, several large, natural, lacustrine systems (i.e., Carolina bay lakes) exist within the geomorphological features known as Carolina bays. Within the current distribution of Carolina bays, Bladen and Columbus counties (North Carolina) contain the only known examples of Carolina bay lakes. The Carolina bay lakes can be split into two major divisions, the “Bladen Lakes Group” which is characterized as being relatively unproductive (dystrophic – oligotrophic), and Lake Waccamaw, which stands alone in Columbus County and is known for its high productivity and species richness. Although there have been several studies conducted on these unique lentic systems, none have documented the flora comprehensively. New information Over the 2013−2014 growing seasons, the littoral zone flora of Carolina bay lakes was surveyed and vouchered. Literature reviews and herbarium crawls complemented this fieldwork to produce an inventory of the vascular plant species. This survey detected 205 taxa (species/subspecies and varieties) in 136 genera and 80 vascular plant families. Thirty-one species (15.2%) are of conservation concern. Lake Waccamaw exhibited the highest species richness with 145 catalogued taxa and 26 species of conservation concern. Across all sites, the Cyperaceae (25 spp.), Poaceae (21 spp.), Asteraceae (13 spp.), Ericaceae (8 spp.), Juncaceae (8 spp.), and Lentibulariaceae (6 spp.) were the six most species-rich vascular plant families encountered. A guide to the littoral zone flora of Carolina bay lakes is presented herein, including dichotomous keys, species accounts (including abundance, habitat, phenology, and exsiccatae), as well as images of living species and vouchered specimens. PMID:27350764

  1. Evidence for mid-Holocene shift in depositional style in Mobile Bay, Alabama

    Science.gov (United States)

    Twichell, David; Kelso, Kyle; Pendleton, Elizabeth A.

    2012-01-01

    The Holocene stratigraphy of Mobile Bay, Alabama, was mapped using a combination of high-resolution seismic data and sediment cores to refine changes in the bay's evolution during this time. The base of the Holocene-era stratigraphy is an erosional surface formed during the last glacial maximum. Overlying Holocene deposits are primarily estuarine mud that has a finely laminated weak acoustic signature. One exception is a thin unit, R1, with varying reflection amplitude that can be traced throughout the southern part of the bay. The continuity of the unit throughout the southern part of the bay suggests a baywide change in sedimentation that was perhaps driven by rapid retreat of the bay-head delta in response to a sudden rise in sea level or an abrupt change in accommodation space due to basin geometry. Along the southern edge of the bay, the R1 unit increases in thickness and reflector amplitude towards Morgan Peninsula. The peninsula itself underwent a period of erosion and narrowing between 4,300 to 3,000 years before present, and the variation in reflector amplitude and the geometry of this part of the R1 unit appear to reflect a period of increased overwashing of the peninsula during this period. Average estuarine sedimentation rates decreased after the formation of the R1 unit, and the decrease coincides with a decline in the rate of sea-level rise. A similar change in depositional style at approximately the same time in neighboring Apalachicola Bay suggests a change that affected the northeastern Gulf of Mexico region and not just Mobile Bay.

  2. Holocene Infilling History of Tampa Bay, Florida

    Science.gov (United States)

    Brooks, G. R.; Larson, R. A.; Cronin, T.; Willard, D.

    2007-05-01

    Tampa Bay is a shallow, sediment-starved estuary located along the central Florida Gulf coast. Based upon sedimentologic, biostratigraphic, and geochronologic analyses of 120 sediment cores and 190 surface sediment samples, karst-controlled basins located in the mid to upper estuary were found to contain a continuous sedimentary record documenting the Holocene sea-level rise and infilling history. The basal unit sampled in cores consists of organic-rich and/or carbonate-rich sediments containing freshwater fauna. Interpreted as lake deposits, the surficial sediments of these units were dated at approximately 8-9 ka suggesting that isolated sinkhole lakes occupied the region prior to being flooded by the Holocene sea-level rise. Overlying the lake deposits, dm-scale, organic-rich muds containing brackish water fauna, represent the transition from fresh to marine conditions as sea level flooded the region. The flooding surface itself is generally undefined, but sometimes represented by a mm-scale layer of shell fragments likely representing a lag deposit. Age dates bracketing this layer show that flooding occurred approximately 6-7 ka. Overlying sediments consist of 3-4 m of organic-rich, sandy muds with typical estuarine fauna. Age dates from the base of this unit indicate estuarine conditions became established approximately 5.5-6 ka. The modern expression of karst basins is a series of shallow, bathymetric depressions, likely reflecting the historically slow rate (0.030-0.065 cm/yr) of fine- grained sediment accumulation. These shallow depressions continue to function as fine-grained sediment sinks, but are now rapidly filling as the rate of accumulation has dramatically increased by approximately one order-of-magnitude (0.16-0.32 cm/yr) within the past 100 years, likely due to human activities.

  3. Seismic Data from the Kane Basin, Northwest Greenland - Insight into a white spot on the map

    Science.gov (United States)

    Ehrhardt, Axel; Schnabel, Michael; Damm, Volkmar

    2013-04-01

    The opening history of the Baffin Bay and the possible extent of oceanic crust within the basin is a key question in order to reconstruct the plate tectonic development of the Arctic region. To contribute to the scientific discussion, a multi-component geophysical and geological survey was carried out in 2010 in the area of the Northern Baffin Bay. Because of the fortunate ice conditions we seized the chance to go to the Kane Basin, half way between the Baffin Bay in the South and the Lincoln Sea in the North, one of a series of basins that are aligned along the Nares Strait. In addition the unclear situation within the Baffin Bay the Nares Strait is one of the most disputed areas in the Arctic. As the opening of the Baffin Bay and the formation of oceanic crust must have been compensated somewhere between Greenland and Ellesmere Island a transform fault was proposed. However, in particular land geological data does not support this thesis and let assume moreover that no lateral displacement occurred between Greenland and Ellesmere Island. In order to shed some more light onto the potential transform fault (the Wegener Fault) two reflection seismic lines were shot within the eastern Kane Basin supported by sonobuoys. Furthermore, magnetic and gravity data is acquired. This paper presents first insight into the eastern side of the Kane Basin. The eastern Kane Basin is characterized by a deeper rim and a more shallow central part of the basin. The term basin is probably misleading as most of it is floored by Proterozoic crust without any sedimentary beds on top of it. Only in the western part of the Kane Basin a sedimentary infill can be recorded which terminates with an erosional truncation on to the seafloor. The significant amount of sediments and debris that is washed into the Kane Basin by rivers and glaciers is transported to the Baffin Bay Fan by the considerably strong N-S current through the Nares Strait. A pull-apart development of the Kane Basin can't be

  4. Application of stable isotopes to the assessment of pollution loading from various sources in the Pampanga River system into the Manila Bay, Philippines

    International Nuclear Information System (INIS)

    The study focuses on the Pampanga River Basin as prototype for the other watersheds of Manila Bay. The pollution of the Bay is associated to loading from agriculture, industry and services sectors but with no direct evidence, hence the origins of pollution have to be identified for area-based resource management actions. The multiple stable isotopes were used and applied in identifying and tracing through spectral signature the origin of nutrient loading

  5. 77 FR 18739 - Safety Zone; Bay Swim V, Presque Isle Bay, Erie, PA

    Science.gov (United States)

    2012-03-28

    ... the January 17, 2008, issue of the Federal Register (73 FR 3316). Public Meeting We do not now plan to... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Swim V, Presque Isle Bay, Erie, PA... is intended to restrict vessels from a portion of the Presque Island Bay during the Bay Swim...

  6. 77 FR 35860 - Safety Zone; Bay Swim V, Presque Isle Bay, Erie, PA

    Science.gov (United States)

    2012-06-15

    ..., Erie, PA in the Federal Register (77 FR 18739). We received no letters commenting on the proposed rule... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Swim V, Presque Isle Bay, Erie, PA... restrict vessels from a portion of the Presque Island Bay during the Bay Swim V swimming event. The...

  7. 78 FR 34575 - Safety Zone; Bay Swim VI, Presque Isle Bay, Erie, PA

    Science.gov (United States)

    2013-06-10

    ... FR Federal Register NPRM Notice of Proposed Rulemaking TFR Temporary Final Rule A. Regulatory History... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Swim VI, Presque Isle Bay, Erie, PA... portion of Presque Isle bay during the Bay Swim VI swimming event. This temporary safety zone is...

  8. Humboldt Bay, California Benthic Habitats 2009 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  9. Humboldt Bay, California Benthic Habitats 2009 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  10. Humboldt Bay, California Benthic Habitats 2009 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  11. Humboldt Bay, California Benthic Habitats 2009 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  12. Concentration and characterization of dissolved organic matter in the surface microlayer and subsurface water of the Bohai Sea, China

    Science.gov (United States)

    Chen, Yan; Yang, Gui-Peng; Wu, Guan-Wei; Gao, Xian-Chi; Xia, Qing-Yan

    2013-01-01

    A total of 19 sea-surface microlayer and corresponding subsurface samples collected from the Bohai Sea, China in April 2010 were analyzed for chlorophyll a, dissolved organic carbon (DOC) and its major compound classes including total dissolved carbohydrates (TDCHO, including monosaccharides, MCHO, and polysaccharides, PCHO) and total hydrolysable amino acids (THAA, including dissolved free, DFAA, and combined fraction, DCAA). The concentrations of DOC in the subsurface water ranged from 130.2 to 407.7 μM C, with an average of 225.9±75.4 μM C, while those in the surface microlayer varied between 140.1 and 330.9 μM C, with an average of 217.8±56.8 μM C. The concentrations of chlorophyll a, DOC, TDCHO and THAA in the microlayer were, respectively correlated with their subsurface water concentrations, implying that there was a strong exchange effect between the microlayer and subsurface water. The concentrations of DOC and TDCHO were negatively correlated with salinity, respectively, indicating that water mixing might play an important role in controlling the distribution of DOC and TDCHO in the water column. Major constituents of DCAA and DFAA present in the study area were glycine, alanine, glutamic acid, serine and histidine. Principal component analysis (PCA) was applied to examine the complex compositional differences that existed among the sampling sites. Our results showed that DFAA had higher mole percentages of glycine, valine and serine in the microlayer than in the subsurface water, while DCAA tended to have higher mole percentages of glutamic acid, aspartic acid, threonine, arginine, alanine, tyrosine, phenylalanine and leucine in the microlayer. The yields of TDCHO and THAA exhibited similar trends between the microlayer and subsurface water. Carbohydrate species displayed significant enrichment in the microlayer, whereas the DFAA and DCAA exhibited non-uniform enrichment in the microlayer.

  13. Performance evaluation of TMPA version 7 estimates for precipitation and its extremes in Circum-Bohai-Sea region, China

    Science.gov (United States)

    Jiang, Dejuan; Zhang, Hua; Li, Ruize

    2016-09-01

    Precipitation and its extremes are of significance for drought and flood warning and monitoring. This study evaluates the capability of Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) 3B42 V7 to detect rainfall events, especially extreme precipitation events, using gauge observations for the period 1998-2012 over Circum-Bohai-Sea region, a mid-altitude and semi-humid monsoon area. The results show that 3B42 V7 performs better at monthly and annual scales than at a daily scale. Spatially or seasonally, the rainfall pattern is more effectively captured by 3B42 V7 for the wet region or season than for the dry region or season. 3B42 V7 displays a positive relative bias in most areas, and the largest is situated in high latitude region, while negative relative bias is found at coastal regions. 3B42 V7 tends to overestimate at low and middle rainfall intensity (RI) ranges (RI root mean square error (RMSE) are higher than 50 % relative to rain gauges for eight extreme precipitation indices except the maximum number of consecutive dry days (CDD), demonstrating that extreme precipitation estimates of 3B42 V7 are generally unreliable. The improvement of 3B42 V7 in capturing extreme precipitation events is anticipated through extensive efforts for its wide range of climate and hydrological applications. Overall, this study provides an evaluation of the quality of TMPA 3B42 V7 in estimating precipitation and its extremes in a mid-altitude and semi-humid monsoon region.

  14. Assessment of the sources of sedimentary organic matter in the Bohai Sea and the northern Yellow Sea using biomarker proxies

    Science.gov (United States)

    Xing, Lei; Hou, Di; Wang, Xinchen; Li, Li; Zhao, Meixun

    2016-07-01

    To evaluate the applicability of source proxies and to assess the sources of sedimentary organic matter in the Bohai Sea (BS) and the northern Yellow Sea (NYS), we analyzed total organic carbon (TOC), total nitrogen (TN), δ13C of TOC, n-alkanes, phytoplankton biomarkers, and glycerol dialkyl glycerol tetraethers (GDGTs) including branched GDGTs (brGDGTs) in 60 surface sediment samples covering the BS and the NYS. Spatial distribution comparison and principal component analysis indicate that with the exception of brGDGTs, terrestrial biomarkers have different spatial distribution pattern from marine biomarkers, suggesting that the sources control the distributions of these biomarkers in spite of hydrodynamic forcing. Significantly positive correlation (R2 = 0.5) between TOC normalized brGDGTs content and TOC normalized crenarchaeol content suggested in situ production of brGDGTs in the BS and the NYS. The δ13C values, TMBR [terrestrial and marine biomarker ratio: (C27 + C29 + C31n-alkanes)/[(C27 + C29 + C31n-alkanes) + (brassicasterol + dinosterol + alkenones)] ] and BIT (branched isoprenoid tetratether index) proxy indicated high terrestrial organic matter (TOM) input near the Huanghe River Estuary, while TOC/TON did not reveal similar distribution pattern. Quantitative estimates of TOM using a binary model revealed much higher TOM percentage from δ13C (avg. 58%) and TMBR (avg. 31%) than from BIT (avg. 7.4%). Our results suggest that, owing to significant in situ production of brGDGTs, the BIT is not a good proxy for indicating soil OM contribution in marine sediments from the BS and the NYS.

  15. Offshore CO2-EOR:Worldwide Progress and a Preliminary Analysis on Its Potential in Offshore Sedimentary Basins off China%离岸二氧化碳驱油的国际进展及我国近海潜力初步分析

    Institute of Scientific and Technical Information of China (English)

    周蒂; 李鹏春; 张翠梅

    2015-01-01

    二氧化碳驱油( CO2-EOR)是一项通过向油层注入二氧化碳而提高石油采收率的技术,它能同时实现CO2的利用和封存,因此是CCUS的重要技术。近年来,随着离岸CO2封存需求的日益增大, CO2-EOR的应用正迅速从陆上扩展到海上。介绍了CO2-EOR的概念和适用条件,综述了国际上离岸CO2-EOR项目和技术,特别是“下一代”CO2-EOR技术的最新进展。通过与国外实例的对比和对盆地石油地质条件的分析,初步探讨了我国近海含油气盆地的CO2-EOR的潜力,认为渤海湾盆地(海域)和珠江口盆地分别具有非混相和混相CO2-EOR的潜力,有可能获得数亿吨石油的增产和实现数亿吨CO2的地下永久封存,需要尽快地开展进一步的研究和评估。%CO2-Enhanced Oil Recovery ( CO2-EOR) is a technique of enhancing oil recovery by injecting CO2 into oil reservoirs.It also realizes both CO2 utilization and CO2 storage and thus is an important technique in the CCUS chain.In recent decade the applica-tion of CO2-EOR is extended rapidly from inland to offshore, as a respond to the increasing demand for offshore CO2 storage.This paper briefed the concept and application conditions of CO2-EOR, and introduced worldwide projects and technical developments on offshore CO2-EOR, including the“Next Generation” CO2-EOR technology.A first-order preliminary review on the potential of CO2-EOR in offshore sedimentary basins off China was given for the first time based on comparison and analysis of petroleum geology of the basins.The Bohai Bay Basin ( offshore) and the Pearl River Mouth Basin are regarded as having the potential of non-miscible and miscible CO2-EOR, respectively.The CO2-EOR application in these basins might be able to bring several hundred million tons of in-cremental oil production and to store several hundred million tons of CO2 underground permanently.Further studies and evaluations are needed urgently.

  16. The stable oxygen and carbon isotopic record from a coral growing in Florida Bay: a 160 year record of climatic and anthropogenic influence

    Science.gov (United States)

    Swart, Peter K.; Healy, Genevieve F.; Dodge, Richard E.; Kramer, Philip; Hudson, J. Harold; Halley, Robert B.; Robblee, Michael B.

    1996-01-01

    A 160 year record of skeletal δ13C and δ18O was examined in a specimen of the coral Solenastrea bournonigrowing in Florida Bay. Variations in the δ18O of the skeleton can be correlated to changes in salinity while changes in the δ13C reflect cycling of organic material within the Bay. Based on the correlation between salinity and skeletal δ18O, we have concluded that there has been no long term increase in salinity in this area of Florida Bay over the past 160 years. Using salinity correlations between the various basins obtained from instrumental data, we have been able to extend our interpretations to other parts of Florida Bay reaching similar conclusions. In contrast to current ideas which have focused on changes in Florida Bay water quality over the past 20-yr history of the Bay as causative in its decline, we have determined that changes in water quality in this basin were already set in motion between 1905 and 1912 by the construction of the Florida East Coast Railway from Miami to Key West. The construction of the railway resulted in the restriction of the exchange of water between the Florida reef tract and the Gulf of Mexico causing Florida Bay to become more eutrophic. Evidence of this process is observed in the sudden shift to relatively lower δ13C values coincident with railway construction. Natural events also appear to have influenced the water in the Bay. Between 1912 and 1948 frequent hurricanes had the effect of increasing exchange of water between the Bay and reef tract and removing large quantities of organic rich sediments. However, since 1948 the number of hurricanes affecting the area has decreased and the products of the oxidation of organic material have been increasingly retained within the basin promoting the initiation of eutrophic conditions.

  17. Site restoration: Restoring Lost Lake, a Carolina bay at the Savannah River Site

    International Nuclear Information System (INIS)

    The Savannah River Site (SRS) in Aiken, SC, is part of the U.S. Department of Energy complex for production of materials for U.S. Government defense activities. From 1958 to 1985 mixed wastes (wastes which are both hazardous and radioactive) generated by aluminum forming/metal finishing processes at SRS were discharged to a settling basin with overflow directed to an adjacent Carolina bay known as Lost Lake. Use of the basin system was discontinued in 1985, and physical closure in situ began in 1988. The project's Closure Plan required that Lost Lake be restored to a 'natural wetland system'. An on-site interdisciplinary team designed the restoration project to demonstrate the effectiveness of various levels of active remediation of Carolina bays as well as restoring Lost Lake. Closure was completed in August 1991, and the site will be maintained for at least 30 years. (author)

  18. Bayes linear statistics, theory & methods

    CERN Document Server

    Goldstein, Michael

    2007-01-01

    Bayesian methods combine information available from data with any prior information available from expert knowledge. The Bayes linear approach follows this path, offering a quantitative structure for expressing beliefs, and systematic methods for adjusting these beliefs, given observational data. The methodology differs from the full Bayesian methodology in that it establishes simpler approaches to belief specification and analysis based around expectation judgements. Bayes Linear Statistics presents an authoritative account of this approach, explaining the foundations, theory, methodology, and practicalities of this important field. The text provides a thorough coverage of Bayes linear analysis, from the development of the basic language to the collection of algebraic results needed for efficient implementation, with detailed practical examples. The book covers:The importance of partial prior specifications for complex problems where it is difficult to supply a meaningful full prior probability specification...

  19. Recognition on the Necessity of Establishing Bohai Sea Comprehensive Management Committee%关于设立渤海综合管理委员会必要性的认识

    Institute of Scientific and Technical Information of China (English)

    徐祥民; 张红杰

    2012-01-01

    In recent years, the demand for the formulation of a special law for the Bohai has become stronger and stronger. As the advocates for the special law for the Bohai, we agree with certain viewpoints in the past writings, but feel that there are still many remained problems can not be avoided about the special law for the Bohai. One of the problems is to establish a special organization for the management of the Bohai using a special law for the Bohai. Because there is not an organisation to implement the integrated management, the past practices in the control and governance of the Bohai Sea were unsuccessful. The previous treatment and protection of Bohai Sea environment was not successful. The multiple damage of Bohai Sea neither could be hindered or remedied by single administrative department or single law enforcement agency, nor could be cured by individual action from several departments. The comprehensive management is proved to be effective. The comprehensive management means to consider the management of Bohai Sea, Bohai coastal zone and Bohai offshore integration according to the sea-and-land interdependence. Any pure land-based activity or sea-based activities disregarding this interdependency is impossible to solve this problem. The space covered by the water of the Bohai Sea forms a whole environment with the coastal lines and coastal land. In many cases, these three parts form a complete eco-system and provide all conditions for the eco-process. We must definitively regard the Bohai Sea as an entire environment and manage this environment according to the requirements of the ecosystem integrity. The best management scheme is comprehensive management which is made up of pollution prevention, ocean exploitation ( sustainable utilization of resources) , ecological protection, and coordinated action of four provinces (municipality city) and twelve cities. Under the current management system, none of land management department treats the Bohai Sea together

  20. Development Status and Countermeasures on Industrial Development of Bohai Black Cattle in Binzhou City%滨州市渤海黑牛产业发展现状及对策

    Institute of Scientific and Technical Information of China (English)

    尤全胜

    2012-01-01

    叙述了滨州市渤海黑牛的发展优势与现状,探索渤海黑牛产研结合、保护开发、打造品牌的产业发展的路子。同时,针对渤海黑牛产业发展中存在的问题,抓住发展关键,提出积极有效的建议与对策,引领产业向区域化、规模化、专业化、标准化方向发展,把渤海黑牛资源优势,品牌优势转化为特色产业优势,市场竞争优势。%This review summarizes the advantage and current situation of Bohai black cattle, explores the way for protection and development of Bohai black cattle. Meanwhile,by targeting the key problem of Bohai black cattle development, it is essential to provide positive effective suggestion and countermeasure, and to guide estate to face area-rization, scale-rization, professionalization, standardization direction devel opment, and make best use of changing the natural resources and brand advantages changes of Bohai black cattle into characteristic industry advantage and market competition advantage.

  1. Recognition on the Necessity of Establishing Bohai Sea Comprehensive Management Committee%关于设立渤海综合管理委员会必要性的认识

    Institute of Scientific and Technical Information of China (English)

    徐祥民; 张红杰

    2012-01-01

    In recent years, the demand for the formulation of a special law for the Bohai has become stronger and stronger. As the advocates for the special law for the Bohai, we agree with certain viewpoints in the past writings, but feel that there are still many remained problems can not be avoided about the special law for the Bohai. One of the problems is to establish a special organization for the management of the Bohai using a special law for the Bohai. Because there is not an organisation to implement the integrated management, the past practices in the control and governance of the Bohai Sea were unsuccessful. The previous treatment and protection of Bohai Sea environment was not successful. The multiple damage of Bohai Sea neither could be hindered or remedied by single administrative department or single law enforcement agency, nor could be cured by individual action from several departments. The comprehensive management is proved to be effective. The comprehensive management means to consider the management of Bohai Sea, Bohai coastal zone and Bohai offshore integration according to the sea-and-land interdependence. Any pure land-based activity or sea-based activities disregarding this interdependency is impossible to solve this problem. The space covered by the water of the Bohai Sea forms a whole environment with the coastal lines and coastal land. In many cases, these three parts form a complete eco-system and provide all conditions for the eco-process. We must definitively regard the Bohai Sea as an entire environment and manage this environment according to the requirements of the ecosystem integrity. The best management scheme is comprehensive management which is made up of pollution prevention, ocean exploitation ( sustainable utilization of resources) , ecological protection, and coordinated action of four provinces (municipality city) and twelve cities. Under the current management system, none of land management department treats the Bohai Sea together

  2. 33 CFR 117.622 - West Bay

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false West Bay 117.622 Section 117.622 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.622 West Bay The draw of the West Bay Bridge, mile...

  3. Water-quality assessment of DOD installations/facilities in the Chesapeake Bay Region. Phase 3. Volume 2. Overall approach, findings and recommendations. Technical report, 1985-1987

    Energy Technology Data Exchange (ETDEWEB)

    1987-11-01

    This report represents the culmination of a two-year, three-phase effort to determine the relative impact of DOD activities on the water quality and living resources of the Chesapeake Bay. Phase I defined the recent historical and present pollution potential of all 66 DOD installations in the Bay's drainage basin, and developed a preliminary screening procedure to categorize these installations according to existing or potential impacts on the Bay and its tributaries. Phase II developed and tested a detailed assessment methodology on six installations to define the character and extent of their impact on the Bay. Phase III applied this tested methodology to the remaining 31 installations identified in Phase I as needing more detailed assessment, and summarizes impacts and program recommendations from an installation, regional, and Bay-wide perspective. This volume presents detailed results of this analysis.

  4. The geology and hydrocarbon possibilities of the Triassic-Jurassic Fundy Basin, eastern Canada

    Energy Technology Data Exchange (ETDEWEB)

    Wade, J.A.; Fensome, R.A. [Geological Survey of Canada, Dartmouth, NS (Canada). Atlantic Geoscience Centre; Brown, D.E. [Canada-Nova Scotia Offshore Petroleum Board, Halifax, NS (Canada)

    1997-09-01

    The development of the Mesozoic sedimentary basins beneath the waters of the eastern coast of North America was discussed. These basins have been linked to the rifting of the central part of Pangaea during Mid and Late Triassic time that ended in the formation of a series of grabens extending from Florida to The Grand Banks of Newfoundland, one of them being the Bay of Fundy Basin which is about 16,500 square kilometres in size. Onshore and offshore geologic mapping and seismic interpretations have shown their age range to be from the Mid Triassic Anisian or Ladinian to Mid Jurassic. Up to 12 km of Mesozoic rocks were deposited in the basin with up to 9 km still present. The depositional history of the area was described. The two areas with greatest hydrocarbon potential are the Bay of Fundy and the Chignecto subbasins.

  5. A reconstruction of late Pleistocene relative sea level in the south Bohai Sea, China, based on sediment grain-size analysis

    Science.gov (United States)

    Yi, Liang; Yu, Hongjun; Ortiz, Joseph D.; Xu, Xingyong; Qiang, Xiaoke; Huang, Haijun; Shi, Xuefa; Deng, Chenglong

    2012-12-01

    Future anthropogenic sea-level rise and its impact on coastal regions is an important issue facing human civilizations. Due to the short nature of the instrumental record of sea-level change, development of proxies for sea-level change prior to the advent of instrumental records is essential to reconstruct long-term background sea-level changes on local, regional and global scales. Here, we employ numerical methods to partition sediment grain size using a combined database of marine surface and core samples, and to quantitatively reconstruct sea-level variation since the late Pleistocene in the south Bohai Sea, China. Our sea-level reconstruction indicates that relative sea-level changes in the southern Bohai Sea track global sea-level variation for the duration of the record. The results also indicate substantial regression from 70 to 30 cal kyr BP, and potentially subarial exposure from 38 to 20 cal kyr BP. Our results document the feasibility of reconstructing relative sea-level change by numerical partitioning of sediment grain size data, demonstrating the potential for future applications.

  6. The effect of Marmara (Izmit) Earthquake on the chemical oceanography of Izmit Bay, Turkey.

    Science.gov (United States)

    Balkis, Nuray

    2003-07-01

    After the Marmara (Izmit) Earthquake (magnitude 7.4) on 17 August 1999, chemical oceanographical characteristics of Izmit Bay were investigated in order to examine the possible effects of the refinery fire and uncontrolled entrance of domestic wastes to the surface waters. The dissolved oxygen (DO) content of the water column in August 1999 was the lowest value of all the measurement periods. It was found to be lower than the detection limit of the method (0.03 mgl(-1)) in the lower layer of eastern and central basins of the Bay, whereas the dissolved hydrogen sulfide (DHS) values were high, varying between 0.14 and 1.28 mgl(-1). The deficiency of DO and in turn formation of DHS were caused by the spreading petroleum from the refinery fire onto the sea surface and waste loads from the damaged municipal waste effluent system. The increasing organic/inorganic loads into the Bay stimulated the phytoplankton blooms which cause locally saturated DO concentrations in the eastern basin during autumn 1999. DO concentrations increased in lower layer waters during winter, whilst DHS formation disappeared when water originating from the Marmara Sea replenish the water column of Izmit Bay. However, DHS formation established again in August 2000.

  7. Mixed layer variability and chlorophyll a biomass in the Bay of Bengal

    OpenAIRE

    Narvekar, J.; Prasanna Kumar, S.

    2014-01-01

    The mixed layer is the most variable and dynamically active part of the marine environment that couples the underlying ocean to the atmosphere and plays an important role in determining the oceanic primary productivity. We examined the basin-scale processes controlling the seasonal variability of mixed layer depth in the Bay of Bengal and its association with chlorophyll using a suite of in situ as well as remote sensing data. A coupling between mixed layer depth and chlorop...

  8. Seasonal thaw settlement at drained thermokarst lake basins, Arctic Alaska

    OpenAIRE

    L. Liu; K. Schaefer; A. Gusmeroli; G. Grosse; Jones, B. M.; Zhang, T.; Parsekian, A.D.; Zebker, H.A.

    2014-01-01

    Drained thermokarst lake basins (DTLBs) are ubiquitous landforms on Arctic tundra lowland. Their dynamic states are seldom investigated, despite their importance for landscape stability, hydrology, nutrient fluxes, and carbon cycling. Here we report results based on high-resolution Interferometric Synthetic Aperture Radar (InSAR) measurements using space-borne data for a study area located on the North Slope of Alaska near Prudhoe Bay, where we focus on the seasonal thaw...

  9. Classification using Hierarchical Naive Bayes models

    DEFF Research Database (Denmark)

    Langseth, Helge; Dyhre Nielsen, Thomas

    2006-01-01

    Classification problems have a long history in the machine learning literature. One of the simplest, and yet most consistently well-performing set of classifiers is the Naïve Bayes models. However, an inherent problem with these classifiers is the assumption that all attributes used to describe......, termed Hierarchical Naïve Bayes models. Hierarchical Naïve Bayes models extend the modeling flexibility of Naïve Bayes models by introducing latent variables to relax some of the independence statements in these models. We propose a simple algorithm for learning Hierarchical Naïve Bayes models...

  10. Backscatter imagery in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 1x1 meter resolution backscatter mosaic of Jobos Bay, Puerto Rico (in NAD83 UTM 19 North). The backscatter values are in relative 8-bit (0 –...

  11. Inorganic Carbon Cycling and Biogeochemical Processes in an Arctic Inland Sea (Hudson Bay)

    Science.gov (United States)

    Burt, William; Thomas, Helmuth; Miller, Lisa; Granskog, Mats; Papakyriakou, Tim; Pengelly, Leah

    2016-04-01

    The distributions of CO2 system parameters in Hudson Bay, which not only receives nearly one third of Canada's river discharge, but is also subject to annual cycles of sea-ice formation and melt, indicate that the timing and magnitude of freshwater inputs play an important role in carbon biogeochemistry and ocean acidification in this unique Arctic ecosystem. This study uses basin-wide measurements of dissolved inorganic carbon (DIC) and total alkalinity (TA), as well as stable isotope tracers (δ18OH2O and δ13CDIC), to provide a detailed assessment of carbon cycling processes throughout the bay. Surface distributions of carbonate parameters reveal the particular importance of freshwater inputs in the southern portion of the bay. Riverine TA end-members vary significantly both regionally and with small changes in near-surface depths, highlighting the importance of careful surface water sampling in highly stratified waters. In an along-shore transect, large increases in subsurface DIC are accompanied by equivalent decreases in δ13CDIC with no discernable change in TA, indicating a respiratory DIC production on the order of 100 μmol/kg during deep water circulation around the bay. Based on TA data we surmise that the deep waters in the Hudson Bay are of Pacific origin.

  12. Understanding the Flushing Capability of Bellingham Bay and Its Implication on Bottom Water Hypoxia

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Taiping; Yang, Zhaoqing

    2015-05-05

    In this study, an unstructured-grid finite-volume coastal ocean model (FVCOM) was used to simulate hydrodynamic circulation and assess the flushing capability in Bellingham Bay, Washington, USA. The model was reasonably calibrated against field observations for water level, velocity and salinity, and was further used to calculate residence time distributions in the study site. The model results suggest that, despite the large tidal ranges (~4 m during spring tide), tidal currents are relatively weak in Bellingham Bay with surface currents generally below 0.5 m/s. The local residence time in Bellingham Bay varies from to near zero to as long as 15 days, depending on the location and river flow condition. In general, Bellingham Bay is a well-flushed coastal embayment affected by freshwater discharge, tides, wind, and density-driven circulation. The basin-wide global residence time ranges from 5-7 days. The model results also provide useful information on possible causes of the emerging summertime hypoxia problem in the north central region of Bellingham Bay. It was concluded that the formation of the bottom hypoxic water should result from the increased consumption rate of oxygen in the bottom oceanic inflow with low dissolved oxygen by organic matters accumulated at the regions characterized with relatively long residence time in summer months.

  13. Inorganic carbon cycling and biogeochemical processes in an Arctic inland sea (Hudson Bay)

    Science.gov (United States)

    Burt, William J.; Thomas, Helmuth; Miller, Lisa A.; Granskog, Mats A.; Papakyriakou, Tim N.; Pengelly, Leah

    2016-08-01

    The distributions of carbonate system parameters in Hudson Bay, which not only receives nearly one-third of Canada's river discharge but is also subject to annual cycles of sea-ice formation and melt, indicate that the timing and magnitude of freshwater inputs play an important role in carbon biogeochemistry and acidification in this unique Arctic ecosystem. This study uses basin-wide measurements of dissolved inorganic carbon (DIC) and total alkalinity (TA), as well as stable isotope tracers (δ18O and δ13CDIC), to provide a detailed assessment of carbon cycling processes within the bay. Surface distributions of carbonate parameters reveal the particular importance of freshwater inputs in the southern portion of the bay. Based on TA, we surmise that the deep waters in the Hudson Bay are largely of Pacific origin. Riverine TA end-members vary significantly both regionally and with small changes in near-surface depths, highlighting the importance of careful surface water sampling in highly stratified waters. In an along-shore transect, large increases in subsurface DIC are accompanied by equivalent decreases in δ13CDIC with no discernable change in TA, indicating a respiratory DIC production on the order of 100 µmol kg-1 DIC during deep water circulation around the bay.

  14. Possible Origin of the High Incidence of Clostridium botulinum Type E in an Inland Bay (Green Bay of Lake Michigan)1

    Science.gov (United States)

    Bott, Thomas L.; Johnson, Jodie; Foster, E. M.; Sugiyama, H.

    1968-01-01

    Bottom and shoreline sediments of Green Bay, northern Lake Michigan, and rivers of the Green Bay drainage basin, as well as soils of the surrounding land mass, were examined for Clostridium botulinum type E. Detection was based on identification of type E toxin in enrichment cultures and was influenced by many factors. Testing smaller amounts of sample in multiple cultures was more productive than examining large inocula in fewer cultures. Incubation at 30 C was unsatisfactory, but 14 days at 20 C or 7 days at 25 C gave good results. Mild heating (60 C for 30 min) of specimens reduced the incidence of positive findings. Freezing enrichment cultures prior to testing for toxicity eliminated many nonbotulinal toxic substances that killed mice. A control culture inoculated with type E spores was employed to show whether a specimen contained factors which could mask the presence of type E. Samples from 708 stations were tested in 2,446 cultures. Type E was found in nearly all underwater specimens of Green Bay and northern Lake Michigan but was present less frequently in samples taken along their shores. The incidence was still lower in the rivers emptying into Green Bay with the organism being rare on the shores of these rivers and in the soils of the land mass proper. Samples from the upper reaches of the rivers practically never contained type E. Runoff could deposit type E spores in Green Bay, but this is not considered to be the major factor in the high incidence of the organism. Multiplication in the bay itself is indicated. PMID:4870273

  15. High molecular weight n-alkanes of high-waxy condensate and its source kitchen orientation in the Qianmiqiao burial-hill zone, Bohai Gulf Basin

    Institute of Scientific and Technical Information of China (English)

    WANG; Tieguan(WANG; T.-G.)

    2004-01-01

    [1]Philp, R. P., Bishop, A. N., Del Rio, J., Characterization of high molecular weight hydrocarbons (>C40) in the oils and reservoir rocks, in The Geochemistry of Reservoirs (eds. Cubitt, J. M., England, W. A.), London: The Geological Society, 1995, 71-85.[2]Hsieh, M., Philp, R. P., Ubiquitous occurrence of high molecular weight hydrocarbons in crude oils, Organic Geochemistry, 2001, 32: 955-966.[3]Lipsky, S. R., Duffy, M. L., High temperature gas chromatography: The development of new aluminum clad flexible fused silica glass capillary columns coated with thermostable nonpolar phases (Part 1), J. of High Resolution Chromatography, 1986, 9: 376-382.[4]Philp, R. P., High temperature gas chromatography for the analysis of fossil fuels: A review, J. of High Resolution Chromatography, 1994, 17: 398-406.[5]Wang Tieguan, Zhu Dan, Lu Hong et al., High molecular weight (C35+) n-alkanes of Neogene heavily biodegraded oil in the Qianmiqiao region, North China, Chinese Science Bulletin, 2002, 47: 1402-1407.[6]The Editorial Board of Petroleam Geology of Dogang Oilfield, Petroleum Geology of China, Vol. 4: Dagang Oilfield, Beijing: Petroleum Industry Press, 1991, 149-153.[7]Yu Zhihai, Yang Chiyin, Liao Qianjun et al., Natural Gas Geology in Huanghua Depression, Beijing: Petroleum Industry Press, 1997, 122-145.[8]Lu Hong, Wang, T. -G., Wang Chunjiang et al., Hydrocarbon sources of high waxy oil and gas pools in Qianmiqiao buried-hill zone, Huanghua depression, Petroleum Exploration and Development (in Chinese), 2001, 28(4): 17-21.[9]Zhang Yousheng, Wang Tieguan, Wang Feiyu, Oil source and entrapment epoch of the Mesozoic oil reservoir in the Kongxi Burial-hill zone, Huanghua Depression, North China, Scientia Geologica Sinica, 1001(4): 257-274.[10]Wang Tieguan, Wang Feiyu, Lu Hong et al., Oil source and entrapment epoch of the Ordovician oil reservoir in the Kongxi Burial-hill zone, Huanghua Depression, North China, Acta Geologica Sinica, 2001, 5(2): 212-219.[11]Wang Tieguan, Li Sumei, Zhang Aiyun et al., A discussion on petroleum migration in the Lunnan oilfield of Xinjiang based on nitrogen compounds, Acta Geologica Sinica (in Chinese), 2000, 74(1): 85-93.[12]England, W. A., Mackenzie, A. S., Mann, D. et al., The movement and entrapment of petroleum fluids in the subsurface, J. of the Geological Society, London, 1987, 144: 327-347.[13]Li, M., Larter, S., Stoddart, D. et al., Fractionation of pyrrolic nitrogen compounds in petroleum during migrations: Derivation of migration-related geochemical parameters, in The Geochemistry of Reservoirs (eds. Cubitt, J. M., England, W. A.), London: The Geological Society, 1995, 103-123.[14]Wang Tieguan, Li Sumei, Zhang Aiyun et al., Oil migration analysis with pyrrolic nitrogen compounds, J. of the University of Petroleum, China (in Chinese), 2000, 24(4): 83-86.

  16. The structure and origin of Prydz Bay and MacRobertson Shelf, East Antarctica

    Science.gov (United States)

    Stagg, H. M. J.

    1985-04-01

    A marine geophysical survey in early 1982, conducted by the Australian Bureau of Mineral Resources, indicated that much of Prydz Bay is underlain by a sedimentary basin. Severe seismic multiples preclude an accurate estimate of total sediment thickness, but interpretation of the seismic and magnetic data suggest that it is probably at least 5 km. The trends of the southeast basin margin and of mild faulting and folding in the southwest indicate an overall NNE trend, roughly orthogonal to the continental margin. In the south of Prydz Bay, two series of seismic sequences are evident, separated by a mildly erosional unconformity. The lower series ranges from poorly- to well-stratified, has minor folding and faulting, and probably derives from continental and perhaps shallow marine pre-breakup sediments. The upper series is generally well-stratified, and prograded near the shelf edge; it probably represents shallow marine post-breakup sediments. The seabed is distinctly unconformable with the underlying sediments, implying both that much of the upper series sediments and some of the lower series sediments have been bulldozed off by advances of the Amery Ice Shelf, and that present sedimentation rates are very low. Possible thin moraines or tillites in the northeast part of the Prydz Bay are also attributed to these glacial advances. The continental slope and rise sedimentary section ranges from at least 3 km thick off Prydz Bay, to thin off the MacRobertson Shelf to the west, reflecting the more prolific sediment source in Prydz Bay. The deep water section includes several seismic sequences, the most distinctive being interpreted as sheet volcanics and turbidite fans. The deepest visible unconformity is locally strongly faulted and may separate the pre-breakup and post-breakup sediments. Indo-Antarctic breakup has been tentatively dated as Early Neocomian (130 Ma) and the E-W orientation of the resultant Antarctic coast invites interpretation of the Lambert Glacier

  17. River sediment supply, sedimentation and transport of the highly turbid sediment plume in Malindi Bay, Kenya

    Institute of Scientific and Technical Information of China (English)

    JOHNSON U.Kitheka

    2013-01-01

    The paper presents results of a study on the sediment supply and movement of highly turbid sediment plume within Malindi Bay in the Northern region of the Kenya coast.The current velocities,tidal elevation,salinity and suspended sediment concentrations (TSSC)were measured in stations located within the bay using Aanderaa Recording Current Meter (RCM-9),Turbidity Sensor mounted on RCM-9,Divers Gauges and Aanderaa Temperature-Salinity Meter.The study established that Malindi Bay receives a high terrigenous sediment load amounting to 5.7 × 106 ton·yr-1.The river freshwater supply into the bay is highly variable ranging from 7 to 680 m3·s-1.The high flows that are > 150 m3·s-1 occurred in May during the South East Monsoon (SEM).Relatively low peak flows occurred in November during the North East Monsoon (NEM) but these were usually <70 m3·s-1.The discharge of highly turbidity river water into the bay in April and May occurs in a period of high intensity SEM winds that generate strong north flowing current that transports the river sediment plume northward.However,during the NEM,the river supply of turbid water is relatively low occurring in a period of relatively low intensity NEM winds that result in relatively weaker south flowing current that transports the sediment plume southward.The mechanism of advection of the sediment plume north or south of the estuary is mainly thought to be due to the Ekman transport generated by the onshore monsoon winds.Limited movement of the river sediment plume southward towards Ras Vasco Da Gama during NEM has ensured that the coral reef ecosystem in the northern parts of Malindi Marine National Park has not been completely destroyed by the influx of terrigenous sediments.However,to the north there is no coral reef ecosystem.The high sediment discharge into Malindi Bay can be attributed to land use change in the Athi-Sabaki River Basin in addition to rapid population increase which has led to clearance of forests to open land

  18. Mathematical Model of Marine Oil Spill in Bohai%渤海海洋溢油的数学模型

    Institute of Scientific and Technical Information of China (English)

    李大鸣; 刘江川; 吴丹; 白玲

    2012-01-01

    A two-dimensional nested regional hydrodynamic model of Bohai was established, in which alternating direction implicit (ADI) method was applied in discrete shallow water circulation equation and chasing method was applied in solving equation groups. The water border of the model was defined by the method of harmonic analysis, and the calculation result matched well with measured values. Oil spill schema adopted in the model described the path of the center of the spilled oil by the effect of wind and flow fields, and the result was validated in a water channel experiment. Mathematical model of marine oil spill was set up based on the hydrodynamic model and oil spill schema. Instantaneous and continuous oil spill from static point source were calculated with and without wind field, then continuous oil spill from moving point source was simulated. This mathematical model provided a complete exemplification for research on oil spill on the sea.%建立了嵌套模式的渤海二维水动力数学模型,模型网格采用显隐交替有限差分格式(即ADI差分格式)进行计算.用追赶法逐段求解,用调和分析法计算模型的水动力边界条件,将潮汐过程计算结果与实测资料进行对比验证其结果吻合良好,溢油数学模型理论公式考虑了实时风场和表面流场作用下油膜质心的迁移和扩散范围,模拟了海上溢油油膜运动轨迹,并用水槽实验验证了公式的正确性,在水动力模型基础上应用溢油运动模式建立了海洋溢油数学模型,对风场作用和无风作用两种条件下的静止点源瞬时溢油和连续溢油运动轨迹和扩散范围进行了计算、分析和比较,并计算了有、无风场作用时移动点源连续溢油污染扩散范围,为海洋溢油数学模型的研究提供了较完整的思路.

  19. 渤海溢油事件的社会影响研究%An Analysis of Social Impact of Bohai Oil Spill Incident

    Institute of Scientific and Technical Information of China (English)

    陈涛

    2013-01-01

    在渤海溢油事件的影响研究中,学术界开展了深入的环境影响和经济影响研究,但忽视了社会影响研究。而渤海溢油事件产生了广泛而深刻的社会影响,进而影响了溢油事件的解决进程。研究发现,渤海溢油事件既在社会舆论、环境抗争、社会稳定、社会心理等层面引发了一系列的社会性问题,也在制度创新、产业布局调整和海洋环境意识等层面产生了积极的倒逼机制。渤海溢油事件的社会影响具有系统性、连锁性、复杂性和潜伏性等特征,因此深入的、持续的追踪研究十分必要,而这更加突出了开展社会影响研究的重要性和紧迫性。%In the research of impact assessment of Bohai oil spill incident ,the academia has carried out an in-depth analysis of environmental and economic impact assessment ,but neglected social impact .How-ever ,the incident has produced far-reaching and profound social impact ,w hich has influenced its resolu-tion .Bohai oil spill incident has not only caused a series of social problems of social public opinion ,envi-ronmental struggle ,social stability ,and social psychology ,but also has produced a positive anti-driving mechanism for system innovation ,industrial layout adjustment and marine environmental awareness .The social effect of Bohai oil spill incident is systematic ,complicated and latent ;therefore ,it is necessary to carry out an in-depth and follow-up study ,w hich show s the importance and urgency of conducting social impact research .

  20. Aquatic predicted no-effect concentrations of 16 polycyclic aromatic hydrocarbons and their ecological risks in surface seawater of Liaodong Bay, China.

    Science.gov (United States)

    Wang, Ying; Wang, Juying; Mu, Jingli; Wang, Zhen; Cong, Yi; Yao, Ziwei; Lin, Zhongsheng

    2016-06-01

    Polycyclic aromatic hydrocarbons (PAHs), a class of ubiquitous pollutants in marine environments, exhibit moderate to high adverse effects on aquatic organisms and humans. However, the lack of PAH toxicity data for aquatic organism has limited evaluation of their ecological risks. In the present study, aquatic predicted no-effect concentrations (PNECs) of 16 priority PAHs were derived based on species sensitivity distribution models, and their probabilistic ecological risks in seawater of Liaodong Bay, Bohai Sea, China, were assessed. A quantitative structure-activity relationship method was adopted to achieve the predicted chronic toxicity data for the PNEC derivation. Good agreement for aquatic PNECs of 8 PAHs based on predicted and experimental chronic toxicity data was observed (R(2)  = 0.746), and the calculated PNECs ranged from 0.011 µg/L to 205.3 µg/L. A significant log-linear relationship also existed between the octanol-water partition coefficient and PNECs derived from experimental toxicity data (R(2)  = 0.757). A similar order of ecological risks for the 16 PAH species in seawater of Liaodong Bay was found by probabilistic risk quotient and joint probability curve methods. The individual high ecological risk of benzo[a]pyrene, benzo[b]fluoranthene, and benz[a]anthracene needs to be determined. The combined ecological risk of PAHs in seawater of Liaodong Bay calculated by the joint probability curve method was 13.9%, indicating a high risk as a result of co-exposure to PAHs. Environ Toxicol Chem 2016;35:1587-1593. © 2015 SETAC. PMID:26517571

  1. San Francisco Bay Area Velocity Structure From Controlled-Source Seismic Refraction Imaging

    Science.gov (United States)

    Goldman, M. R.; Catchings, R. D.; Steedman, C. E.; Gandhok, G.; Boatwright, J.; Rymer, M. J.

    2004-12-01

    To better understand the velocities and structures of the crust and upper mantle in the San Francisco Bay area, we developed 2-D tomographic velocity models along four seismic refraction profiles acquired along and across the bay area in the early 1990's. The four profiles extended from (1) Hollister to Inverness along the San Francisco and Marin Peninsulas (~200 km long), (2) Hollister to Santa Rosa along the East Bay (~220 km long), (3) the Pacific Ocean to Livermore crossing the bay (~100 km long), and (4) the Pacific Ocean to the western Santa Clara Valley (~25 km long), centered on the epicenter of the1989 M. 6.9 Loma Prieta earthquake. Velocity models were not previously developed for three of the seismic profiles, and the previously developed model for the fourth profile (Catchings and Kohler, 1996) did not include some of the currently available seismic data. The profiles along the bay image structures from the near surface to about 25 km depth, and they show velocity anomalies associated with the major faults (San Andreas, Hayward, Rodgers Creek, Calaveras) and basins along the profile. Velocities range from about 2 km/s in the basins to about 7 km/s at the Moho, which dips southward along both sides of the bay. The cross bay profile shows velocity anomalies associated with six fault zones between the Pacific Ocean and the Livermore Valley and higher upper-crustal velocities (~6.2 km/s) between the San Andreas and Hayward faults than to the southwest (~5 km/s) or northeast (~4 km/s) of those faults. The Loma Prieta profile shows velocities ranging from 2 km/s to 6 km/s in the upper 5 km, with the highest velocities in the epicentral region of the 1989 Loma Prieta earthquake. A pronounced, northeast-dipping, low-velocity zone is located beneath the surface expression of the San Andreas fault zone, but other fault zones along the profile show high-velocity anomalies beneath their surface expressions. Collectively, the velocity images show the complexity of

  2. Drifting and meandering of Olive Ridley Sea turtles in the Bay of Bengal: Role of oceanic Rossby waves

    Digital Repository Service at National Institute of Oceanography (India)

    Ram, P.S.; Rao, S.A.; Sadhuram, Y.

    .wii.gov.in/webs /about.htm (last accessed on 24 th October 2008). The Bay of Bengal is a semi-enclosed tropical basin in the northern Indian Ocean. The circulation in the Bay is driven by local monsoonal winds, equatorial winds, rainfall and river discharge (Haugen.... Unfortunately, we do not have access to the accurate positions of these turtles, that otherwise would allow us to compare the speeds of the turtles with geostrophic velocities. The majority of the eddy patterns explained above appears to be propagating from...

  3. Distinctive suit and the common people--On Wang Zhi-pu’s drama"Bohai Princess"%个性鲜明雅俗共赏--评王治普大型话剧《渤海公主》

    Institute of Scientific and Technical Information of China (English)

    张放

    2013-01-01

    Bohai's history and culture is not only the crystallization of the wisdom of Heilongjiang people, is a bright pearl in the history of Chinese civilization, the drama"Mudanjiang playwright creation of Mr. Wang Zhipu Bohai Princess", with rich strokes, vivid characters and elegance of all art to reproduce a historical disputes in eighth Century twenty or thirty's Bohai country and the relationship with Tang Dynasty. This drama not only has the bright Bohai culture and personality, but also suit and the common people, the viewer can feel the drama and the Bohai culture and the unique artistic charm, to promote the culture of Bohai, and make more people understand the splendid time unique civilization made a praiseworthy for one's excellent to conduct attempt.%渤海国的历史文化不仅是黑龙江人民智慧的结晶,更是中华文明史上一颗璀璨的明珠,由牡丹江剧作家王治普先生创作的大型话剧《渤海公主》,用丰富的笔触,鲜明的人物特色以及雅俗共赏的艺术品位再现了公元八世纪二三十年代渤海国与唐朝关系的一段历史纠葛。这部话剧不仅具有鲜明的渤海文化个性,而且雅俗共赏,使观者在“看得懂”的同时更能感受到话剧以及渤海文化独特的艺术魅力,为普及渤海文化,让更多人了解那一段灿烂其时的独特文明做了一次难能可贵的尝试。

  4. Nelson River and Hudson Bay

    Science.gov (United States)

    2002-01-01

    Rivers that empty into large bodies of water can have a significant impact on the thawing of nearshore winter ice. This true-color Moderate Resolution Imaging Spectroradiometer (MODIS) image from May 18, 2001, shows the Nelson River emptying spring runoff from the Manitoba province to the south into the southwestern corner of Canada's Hudson Bay. The warmer waters from more southern latitudes hasten melting of ice near the shore, though some still remained, perhaps because in shallow coastal waters, the ice could have been anchored to the bottom. High volumes of sediment in the runoff turned the inflow brown, and the rim of the retreating ice has taken on a dirty appearance even far to the east of the river's entrance into the Bay. The sediment would have further hastened the melting of the ice because its darker color would have absorbed more solar radiation than cleaner, whiter ice. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  5. Biodiversity patterns of free-living marine nematodes in a tropical bay: Cienfuegos, Caribbean Sea

    Science.gov (United States)

    Armenteros, M.; Ruiz-Abierno, A.; Fernández-Garcés, R.; Pérez-García, J. A.; Díaz-Asencio, L.; Vincx, M.; Decraemer, W.

    2009-11-01

    Spatial and temporal biodiversity patterns of free-living marine nematodes were studied in Cienfuegos Bay, a tropical semi-enclosed basin in the Caribbean Sea. Taxonomic (to species level) and functional (biological trait) approaches were applied for describing the assemblage structure and relating it to abiotic environment based on a sampling scheme in six subtidal stations and three months. Biological trait approach added relevant information to species pattern regarding relationships between diversity patterns and the abiotic environment. The most common morphotypes were deposit feeding nematodes, with colonising abilities of 2-3 (in a scale from 1 to 5), tail conical cylindrical or filiforme and body slender; and their abundance were correlated with depth, organic matter and silt/clay fraction. In spite of a high turnover of species, functional diversity of assemblages did not change notably in space and time. A result probably due to sampling of the habitat pool of species and to low heterogeneity of the studied muddy bottoms. Chemical pollution (organic enrichment and heavy metals) and hydrodynamic regime possibly drove the biodiversity patterns. Spatial distribution of assemblages support the existence of two well differentiated basins inside the bay, the northern basin more polluted than the southern one. The low hydrodynamic regime would determine a poor dispersion of nematodes resulting in high spatial variance in the assemblage structure; and also the associated hypoxic conditions and pollutants in sediments can explain the dominance of tolerant nematode species such as Daptonema oxycerca, Sabatieria pulchra, Terschellingia gourbaultae, and Terschellingia longicaudata. A comparison of spatial-temporal patterns of biodiversity between Cienfuegos Bay and other semi-enclosed bays in temperate regions suggests several similarities: nematode assemblages are strongly influenced by anthropogenic disturbance, temporal trends are weak or overridden by spatial

  6. Simulation of Pollutant Transport in Marmaris Bay

    Institute of Scientific and Technical Information of China (English)

    Lale BALAS

    2001-01-01

    The circulation pattern and the pollutant transport in the Marmaris Bay are simulated by the developed three-dimensional baroclinic model. The Marmaris Bay is located at the Mediterranean Sea coast of Turkey. Since the sp ring tidal range is typically 20~30 cm, the dominant forcing for the circulation and water exchange is due to the wind action. In the Marmaris Bay, there is sea outfall discharging directly into the bay, and that threats the bay water quality significantly. The current patterns in the vicinity of the outfall have been observed by tracking drogues which are moved by currents at different water depths. In the simulations of pollutant transport, the coliforms-counts is used as the tracer.The model provides realistic predictions for the circulation and pollutant transport in the Marmaris Bay. The transport model component predictions well agree with the results of a laboratory model study.

  7. Application of adjoint assimilation technique in simulating tides and tidal currents of the Bohai Sea, the Yellow Sea and the East China Sea

    Institute of Scientific and Technical Information of China (English)

    Cheng Yongcun; Lu Xianqing; Liu Yuguang; Xu Qing

    2007-01-01

    Considering the interaction of different tidal waves, an adjoint numerical model is developed to simulate M2, S2, K1 and O1 tidal waves in the Bohai Sea, the Yellow Sea and the East China Sea(B-Y-E) simultaneously. Compared with previous researches, by using the adjoint assimilation technique to inverse open boundary conditions and bottom friction coefficients based on altimetric data from TOPEX/Poseidon (T/P)and tidal gauges data, the precision of the numerical simulation is significantly improved. Selecting 14 days of simulated results after t11e initial warming run to conduct harmonic analysis, the results can show the characteristics of M2, S2, K1 and O1 tidal wave systems perfectly in B-Y-E. Compared with 9 current stations, the calculated harmonic constants of tidal currents for M2 and K1 are in good agreement With the observed ones.

  8. Lithospheric Architecture Beneath Hudson Bay

    Science.gov (United States)

    Porritt, R. W.; Miller, M. S.; Darbyshire, F. A.

    2015-12-01

    Hudson Bay overlies some of the thickest Precambrian lithosphere on Earth, whose internal structures contain important clues to the earliest workings of plate formation. The terminal collision, the Trans-Hudson Orogen, brought together the Western Churchill craton to the northwest and the Superior craton to the southeast. These two Archean cratons along with the Paleo-Proterozoic Trans-Hudson internides, form the core of the North American craton. We use S to P converted wave imaging and absolute shear velocity information from a joint inversion of P to S receiver functions, new ambient noise derived phase velocities, and teleseismic phase velocities to investigate this region and determine both the thickness of the lithosphere and the presence of internal discontinuities. The lithosphere under central Hudson Bay approaches 􏰂350 km thick but is thinner (􏰂200-250 km) around the periphery of the Bay. Furthermore, the amplitude of the lithosphere-asthenosphere boundary (LAB) conversion from the S receiver functions is unusually large for a craton, suggesting a large thermal contrast across the LAB, which we interpret as direct evidence of the thermal insulation effect of continents on the asthenosphere. Within the lithosphere, midlithospheric discontinuities, significantly shallower than the base of the lithosphere, are often imaged, suggesting the mechanisms that form these layers are common. Lacking time-history information, we infer that these discontinuities reflect reactivation of formation structures during deformation of the craton.

  9. San Francisco and Bay Area, CA, USA

    Science.gov (United States)

    1991-01-01

    Although clouds obscure part of the city of San Francisco and the mouth of the Bay (37.5N, 122.0W), many cultural and natural features in the immediate vicinity are obvious. The Bay Bridge which was damaged in the 1989 earthquake, Candlestick Park, San Mateo and Dumbarton Bridges as well as the various colored settling ponds rimming the south end of the Bay, the San Andreas and Calaveras faults and many of the major highways can be seen.

  10. Occurrence and spatial distribution of organophosphate ester flame retardants and plasticizers in 40 rivers draining into the Bohai Sea, north China

    International Nuclear Information System (INIS)

    Organophosphate esters (OPEs) are alternatives to polybrominated diphenyl ethers, often used as flame-retardants and plasticizers. There are few reports of OPEs in river water. This study focused on the occurrence and spatial distribution of 11 OPE congeners and one synthetic intermediate triphenylphosphine oxide (TPPO) in 40 major rivers entering into the Bohai Sea. Total OPEs ranged from 9.6 to 1549 ng L−1, with an average of 300 ng L−1. Tris(1-chloro-2-propyl) phosphate (TCPP) (4.6–921 ng L−1, mean: 186 ng L−1) and tris(2-choroethyl) phosphate (TCEP) (1.3–268 ng L−1, mean: 80.2 ng L−1) were the most abundant OPEs and their distribution patterns are similar, indicating the same source (r = 0.61, P < 0.05) and the influence of large production and consumption of chlorinated OPEs in the region. Priority should be given to TCPP, PCEP and TPPO due to their high concentrations in the rivers and potential threat to aquatic organisms. - Highlights: • High levels of OPEs have been determined in river waters around Bohai Sea. • Triphenylphosphine oxide presented very high concentrations in specific rivers. • The total riverine inputs of OPEs and TPPO were estimated. - Organophosphate ester flame-retardants and plasticizers are ubiquitous in the aquatic environment and of concern as contaminants discharged into the coastal environment

  11. Modeling of Fishing Effects on Fishery Resources and Ecosystems of the Bohai Sea%渔业捕捞对渤海渔业资源及生态系统影响的模型研究

    Institute of Scientific and Technical Information of China (English)

    许思思; 宋金明; 李学刚; 袁华茂; 李宁; 张英

    2011-01-01

    本文运用调查数据与Ecopath生态通道模型,定量揭示了近50年来渤海生态系统的变化特征,探讨了渔业捕捞对其变化的影响.研究表明,渤海生态系统最关键的功能组已由20世纪50年代末的高营养级游泳动物食性鱼类,转变为20世纪80年代初和90年代中等营养级的底栖大型甲壳类;近50年来渤海生态系统的能量传递效率在波动中显著下降;渤海生态系统的规模、成熟度、总能流量、费恩循环指数、生态网络的聚合度等属性指标均波动剧烈,表明渤海生态系统目前并不成熟,尚处于不稳定期.渔业捕捞是渤海生态系统变化的重要影响因素.因此,应降低渤海渔业捕捞的强度,防止发生持续大强度捕捞导致的渤海渔业资源衰退和生态系统崩溃,以实现渤海渔业资源的可持续利用和生态系统的正常运转.%Based on integrated analysis of historical data and the Ecopath model, this study examined changes in Bohai Sea ecosystems over recent 50 years and the effects of fishing on such changes. It would be of significance to promote the transition to an ecosystem-level study when investigating fishing impacts, and of practical significance for managers to make reasonable decisions on fishery resources protection. Ecopath models have similar output values of biomass,ecotrophic efficiency, and attributes of the same functional groups under different fishing intensity in the same year. Estimated from the output of Ecopath models, the keystoneness and relative overall effect of each functional group show that the most key functional groups of Bohai Sea ecosystems changed from high trophic level fishes of nekton feeding habits in the late 1950s, to macro benthic crustaceans with medium trophic levels in the early 1980s and in the 1990s .The increasing fishing intensity is the important factor causing the transition of the most key functional groups. The energy transfer efficiency of Bohai Sea

  12. 33 CFR 80.1114 - San Pedro Bay-Anaheim Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false San Pedro Bay-Anaheim Bay, CA. 80.1114 Section 80.1114 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1114 San Pedro Bay—Anaheim Bay, CA. (a) A line drawn across the...

  13. 77 FR 70891 - Safety Zone; Bay Bridge Construction, San Francisco Bay, San Francisco, CA

    Science.gov (United States)

    2012-11-28

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Bridge Construction, San Francisco Bay..., CA in support of the Bay Bridge Construction Safety Zone from November 1, 2012 through July 31, 2013...: Table of Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of...

  14. A numerical study on the impact of tidal waves on the storm surge in the north of Liaodong Bay

    Institute of Scientific and Technical Information of China (English)

    KONG Xiangpeng

    2014-01-01

    A storm surge is an abnormal sharp rise or fall in the seawater level produced by the strong wind and low pressure field of an approaching storm system. A storm tide is a water level rise or fall caused by the com-bined effect of the storm surge and an astronomical tide. The storm surge depends on many factors, such as the tracks of typhoon movement, the intensity of typhoon, the topography of sea area, the amplitude of tidal wave, the period during which the storm surge couples with the tidal wave. When coupling with different parts of a tidal wave, the storm surges caused by a typhoon vary widely. The variation of the storm surges is studied. An once-in-a-century storm surge was caused by Typhoon 7203 at Huludao Port in the north of the Liaodong Bay from July 26th to 27th, 1972. The maximum storm surge is about 1.90 m. The wind field and pressure field used in numerical simulations in the research were derived from the historical data of the Typhoon 7203 from July 23rd to 28th, 1972. DHI Mike21 is used as the software tools. The whole Bohai Sea is defined as the computational domain. The numerical simulation models are forced with sea levels at water boundaries, that is the tide along the Bohai Straits from July 18th to 29th (2012). The tide wave and the storm tides caused by the wind field and pressure field mentioned above are calculated in the numerical simulations. The coupling processes of storm surges and tidal waves are simulated in the following way. The first simulation start date and time are 00:00 July 18th, 2012;the second simulation start date and time are 03:00 July 18th, 2012. There is a three-hour lag between the start date and time of the simulation and that of the former one, the last simulation start date and time are 00:00 July 25th, 2012. All the simulations have a same duration of 5 days, which is same as the time length of typhoon data. With the first day and the second day simulation output, which is affected by the initial field, being

  15. Chesapeake Bay Program Water Quality Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Chesapeake Information Management System (CIMS), designed in 1996, is an integrated, accessible information management system for the Chesapeake Bay Region....

  16. Polychlorinated biphenyls (PCBs) in San Francisco Bay.

    Science.gov (United States)

    Davis, J A; Hetzel, F; Oram, J J; McKee, L J

    2007-09-01

    San Francisco Bay is facing a legacy of polychlorinated biphenyls (PCBs) spread widely across the land surface of the watershed, mixed deep into the sediment of the Bay, and contaminating the Bay food web to a degree that poses health risks to humans and wildlife. In response to this persistent problem, water quality managers are establishing a PCB total maximum daily load (TMDL) and implementation plan to accelerate the recovery of the Bay from decades of PCB contamination. This article provides a review of progress made over the past 15 years in managing PCBs and understanding their sources, pathways, fate, and effects in the Bay, and highlights remaining information needs that should be addressed in the next 10 years. The phaseout of PCBs during the 1970s and the 1979 federal ban on sale and production led to gradual declines from the 1970s to the present. However, 25 years after the ban, PCB concentrations in some Bay sport fish today are still more than ten times higher than the threshold of concern for human health. Without further management action it appears that the general recovery of the Bay from PCB contamination will take many more decades. PCB concentrations in sport fish were, along with mercury, a primary cause of a consumption advisory for the Bay and the consequent classification of the Bay as an impaired water body. Several sources of information indicate that PCB concentrations in the Bay may also be high enough to adversely affect wildlife, including rare and endangered species. The greater than 90% reduction in food web contamination needed to meet the targets for protection of human health would likely also generally eliminate risks to wildlife. PCB contamination in the Bay is primarily associated with industrial areas along the shoreline and in local watersheds. Strong spatial gradients in PCB concentrations persist decades after the release of these chemicals to Bay Area waterways. Through the TMDL process, attention is being more sharply

  17. Vertical Deformation of Late Quaternary Features Across Port-au-Prince Bay, Haiti

    Science.gov (United States)

    Cormier, M.; McHugh, C. M.; Gulick, S. P.; Braudy, N.; Davis, M. B.; Diebold, J. B.; Dieudonne, N.; Douilly, R.; Hornbach, M. J.; Johnson, H. E.; Mishkin, K.; Seeber, L.; Sorlien, C. C.; Steckler, M. S.; Symithe, S. J.; Templeton, J.

    2010-12-01

    As part of a project that investigated the underwater impacts of the January 12, 2010 earthquake in Haiti, we surveyed offshore structures that may have been activated during that earthquake or that might become activated in future earthquakes. Part of that survey focused on the shallow shelf area that extends north of the segment of the Enriquillo-Plantain Garden fault that just ruptured. This area is occupied by an elongated depression, 25 km long, 10 km wide, and 140 m deep. The NW-SE axis of that shallow basin is sub-parallel to that of the NW-SE anticlines that bounds Port-au-Prince Bay. The shallow basin is also rimmed by a carbonate platform that is 5-10 km-wide and ~30m deep. New multibeam bathymetric and sidescan sonar data collected across that platform highlight a series of circular dissolution structures 1-2 km across and ~80 m deep. We interpret that morphology to indicate antecedent karst topography that developed during previous glacial maxima. According to that scenario, the shallow basin off Port-au-Prince would have been isolated from the Caribbean Sea by the continuous platform, and would probably have been occupied by a lagoon. Indeed, a few high-resolution chirp profiles image what may be a paleoshoreline at about 80m depth, buried beneath a 5-8 m thick, acoustically transparent, presumably Holocene layer. Preliminary analysis indicates that the basin floor and the base of the presumably Holocene layer are perfectly horizontal in the center of the basin, but tilted down to the south at its northern edge. The presumed paleoshoreline is also shallower to the north of the basin. We propose that this tilt is driven by contraction across the NW-SE fold-and-thrust belt that runs across Hispaniola. This hypothesis remains to be tested with a more thorough geophysical and coring survey in Port-au-Prince Bay.

  18. Restoration of Lost Lake, recovery of an impacted Carolina Bay

    International Nuclear Information System (INIS)

    Lost Lake is one of approximately 200 Carolina bays found on the Savannah River Site (SRS). Until 1984 Lost Lake was contaminated by heavy metals and solvents overflowing from a nearby settling basin. Up to 12 inches of surface soil and all vegetation was removed from the bay as part of a RCRA removal action. A plan for restoration was initiated in 1989 and implemented in 1990 and 1991. Extensive planning led to defined objectives, strategies, treatments, and monitoring programs allowing successful restoration of Lost Lake. The primary goal of the project was to restore the wetland ecosystem after a hazardous waste clean up operation. An additional goal was to study the progress of the project and the success of the restoration activity. Several strategy considerations were necessary in the restoration plan. The removal of existing organic soils had to have compensation, a treatment scheme for planting and the extent of manipulation of the substrate had to be considered, monitoring decisions had to be made, and the decision whether or not to actively control the hydrology of the restored system

  19. Forewarning model for water pollution risk based on Bayes theory.

    Science.gov (United States)

    Zhao, Jun; Jin, Juliang; Guo, Qizhong; Chen, Yaqian; Lu, Mengxiong; Tinoco, Luis

    2014-02-01

    In order to reduce the losses by water pollution, forewarning model for water pollution risk based on Bayes theory was studied. This model is built upon risk indexes in complex systems, proceeding from the whole structure and its components. In this study, the principal components analysis is used to screen out index systems. Hydrological model is employed to simulate index value according to the prediction principle. Bayes theory is adopted to obtain posterior distribution by prior distribution with sample information which can make samples' features preferably reflect and represent the totals to some extent. Forewarning level is judged on the maximum probability rule, and then local conditions for proposing management strategies that will have the effect of transforming heavy warnings to a lesser degree. This study takes Taihu Basin as an example. After forewarning model application and vertification for water pollution risk from 2000 to 2009 between the actual and simulated data, forewarning level in 2010 is given as a severe warning, which is well coincide with logistic curve. It is shown that the model is rigorous in theory with flexible method, reasonable in result with simple structure, and it has strong logic superiority and regional adaptability, providing a new way for warning water pollution risk. PMID:24194413

  20. Numerical simulation of the dual-core structure of the Bohai Sea cold bottom water in summer

    Institute of Scientific and Technical Information of China (English)

    ZHOU Feng; HUANG DaJi; SU JiLan

    2009-01-01

    Regional Ocean Modeling Systems (ROMS 3.0) and the K-ε turbulence closure scheme has been ap-plied to investigating the seasonal evolution of the thermsocline in the Bohsi Sea. The simulation re-produces the stratifications lasting from early April to early September and reveals the existence of marked Asymmetric Dual-Core Cold Bottom Water (ADCCBW) in the south and north depression basin respectively under the thermocline. The bottom temperature in the north depression is about 1-4℃ lower than that in the south depression basin which is in good agreement with observations. Model results suggest that the local bathymetry characteristics and inhomogeneous net heat flux due to the latitude difference are the major cause for the early formation of the ADCCBW. Numerical Lagrangian drifter experiments support the finding that the ADCCBW is maintained throughout the stratification periods by the inflow of cold bottom water from the northern Yellow Sea and deep channel in the western side of Liaodong Peninsula. The inflow cold water contributes to the north depression basin distinctively larger than to the south one. Tidal mixing enhances the bottom temperature asymmetry between the two basins.

  1. Bohai Immigrants during Late Liao and Early Jin Dynasties and Their Descendants' Social Conditions in Jin Dynasty%辽末金初的渤海移民及其后裔在金代的社会情况

    Institute of Scientific and Technical Information of China (English)

    孙炜冉

    2015-01-01

    Bohai immigrants during the late Liao and early Jin Dynasties mostly due to the reason of war, they were forced to migrate, so these immigrants did not like the early immigrants have the plan and co-or-dination, directly resulted in the Bohai people and other ethnic people mixed in one place, then it was difficult to form a large-scale habitation of ethnic groups, which eventually broke the ethnic structure of Bohai people, accelerating the disappearance of their national identity and integration with other ethnic groups, only Liaoyang clans Bohai people tenaciously sustained the final clan relationships. Af-ter Liao Dynasty more than two hundred years of ruling, the Bohai people have not disappeared in the course of history, and during the late Liao and early Jin Dynasties, served as a very important histori-cal role in accelerating the perish of Liao Dynasty and the rise of Jin Dynasty. So, in the Jin Dynasty Bohai people had a relatively high social status, especially had close marriage relationship with the Wanyan royal, which resulted in the Bohai people active in politics. There were numerous influential civilian officials and military officers, as well as celebrity culture in the Jin Dynasty, which was the true reflection of privileged Bohai people.%渤海人在辽末金初的移民,多系因战争关系被迫迁徙它地,因为这些移民不是像辽初移民那样具有计划性和统筹性,所以直接造成了渤海人与汉人等其他民族杂混于一处,再难以民族群体的形式大规模聚居,从而最终打破了渤海人的族群组织结构,加速了其民族特征的消失及与其他民族的融合,惟有辽阳世族的渤海人顽强维系着最后的宗族关系。经过辽代二百余年时间的统治,渤海人仍未消失于历史的长河之中,而且,在辽亡金兴之际,充当了非常重要的历史角色,加速了辽的败亡和金的崛起。所以,在金朝其民族却有着相对较高的社会地

  2. Bohai Immigrants during Late Liao and Early Jin Dynasties and Their Descendants' Social Conditions in Jin Dynasty%辽末金初的渤海移民及其后裔在金代的社会情况

    Institute of Scientific and Technical Information of China (English)

    孙炜冉

    2015-01-01

    渤海人在辽末金初的移民,多系因战争关系被迫迁徙它地,因为这些移民不是像辽初移民那样具有计划性和统筹性,所以直接造成了渤海人与汉人等其他民族杂混于一处,再难以民族群体的形式大规模聚居,从而最终打破了渤海人的族群组织结构,加速了其民族特征的消失及与其他民族的融合,惟有辽阳世族的渤海人顽强维系着最后的宗族关系。经过辽代二百余年时间的统治,渤海人仍未消失于历史的长河之中,而且,在辽亡金兴之际,充当了非常重要的历史角色,加速了辽的败亡和金的崛起。所以,在金朝其民族却有着相对较高的社会地位。渤海人与女真人,尤其是与完颜氏皇族有着密切的联姻关系,这便造成了渤海人在金朝政权中有活跃的政治活动。有金一代,涌现出众多极具影响的渤海裔文臣武将,以及文化名人,这是渤海人在金朝社会享有特权的真实反映。%Bohai immigrants during the late Liao and early Jin Dynasties mostly due to the reason of war, they were forced to migrate, so these immigrants did not like the early immigrants have the plan and co-or-dination, directly resulted in the Bohai people and other ethnic people mixed in one place, then it was difficult to form a large-scale habitation of ethnic groups, which eventually broke the ethnic structure of Bohai people, accelerating the disappearance of their national identity and integration with other ethnic groups, only Liaoyang clans Bohai people tenaciously sustained the final clan relationships. Af-ter Liao Dynasty more than two hundred years of ruling, the Bohai people have not disappeared in the course of history, and during the late Liao and early Jin Dynasties, served as a very important histori-cal role in accelerating the perish of Liao Dynasty and the rise of Jin Dynasty. So, in the Jin Dynasty Bohai people had a relatively high social

  3. Catchment clearing accelerates the infilling of a shallow subtropical bay in east coast Australia

    Science.gov (United States)

    Coates-Marnane, Jack; Olley, Jon; Burton, Joanne; Sharma, Ashneel

    2016-06-01

    Understanding processes that govern the transport and distribution of terrestrial sediments to and within bays is critical for interpreting the drivers of long-term changes in these ecosystems. On the east coast of Australia increased soil erosion and sediment delivery following extensive land clearing in the contributing catchments, associated with European settlement, is highlighted as a key driver of the decline of numerous nearshore habitats including seagrass meadows and in-shore coral reefs. Here we use optical, radiocarbon and radionuclide dating to estimate mass accumulation rates and type of terrestrial sedimentation in central Moreton Bay during the Holocene. We compare the long-term rates of infilling within the central basin with the recent past and show a 3-9 fold increase in sediment accretion over the last 100 years compared to the long term (last ∼ 1500 to 3000 yrs) average. Infilling during the Holocene is not spatially uniform, with preferential deposition occurring within the now submerged palaeochannels of the Brisbane and Pine rivers. We suggest that modern turbidity regimes in Moreton Bay are the result of the compounded effect of both a historical increase in fine sediment supply and a rapid decline in the effective storage capacity of the basin.

  4. Temporal trends for inflow of perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) to Tokyo Bay, Japan, estimated by a receptor-oriented approach.

    Science.gov (United States)

    Sakurai, Takeo; Serizawa, Shigeko; Kobayashi, Jun; Kodama, Keita; Lee, Jeong-Hoon; Maki, Hideaki; Zushi, Yasuyuki; Sevilla-Nastor, Janice Beltran; Imaizumi, Yoshitaka; Suzuki, Noriyuki; Horiguchi, Toshihiro; Shiraishi, Hiroaki

    2016-01-01

    We estimated inflow rates of perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) to Tokyo Bay, Japan, between February 2004 and February 2011 by a receptor-oriented approach based on quarterly samplings of the bay water. Temporal trends in these inflow rates are an important basis for evaluating changes in PFOS and PFOA emissions in the Tokyo Bay catchment basin. A mixing model estimated the average concentrations of these compounds in the freshwater inflow to the bay, which were then multiplied by estimated freshwater inflow rates to obtain the inflow rates of these compounds. The receptor-oriented approach enabled us to comprehensively cover inflow to the bay, including inflow via direct discharge to the bay. On a logarithmic basis, the rate of inflow for PFOS decreased gradually, particularly after 2006, whereas that for PFOA exhibited a marked stepwise decrease from 2006 to 2007. The rate of inflow for PFOS decreased from 730kg/y during 2004-2006 to 160kg/y in 2010, whereas that for PFOA decreased from 2000kg/y during 2004-2006 to 290kg/y in 2010. These reductions probably reflected reductions in the use and emission of these compounds and their precursors in the Tokyo Bay catchment basin. Our estimated per-person inflow rates (i.e., inflow rates divided by the estimated population in the basin) for PFOS were generally comparable to previously reported per-person waterborne emission rates in Japan and other countries, whereas those for PFOA were generally higher than previously reported per-person waterborne emission rates. A comparison with previous estimates of household emission rates of these compounds suggested that our inflow estimates included a considerable contribution from point industrial sources.

  5. Laurentide Ice Sheet dynamics in the Bay of Fundy, Canada, revealed through multibeam sonar mapping of glacial landsystems

    Science.gov (United States)

    Todd, Brian J.; Shaw, John

    2012-12-01

    Recent multibeam sonar data collected in the Bay of Fundy, Canada, interpreted in conjunction with geophysical profiling and sediment sampling, reveal in unprecedented detail a suite of glacial landforms associated with the southwest margin of the Laurentide Ice Sheet. These landforms constitute four glacial landsystems. 1) Subglacial landsystem I: In southwestern Bay of Fundy, the elongated Grand Manan Basin contains ice-contact sediments of possible mid-Wisconsinan age overlain by late-Wisconsinan ice-contact sediments strongly imprinted by iceberg furrows and pits. In places, possible mid-Wisconsinan glaciomarine sediments have been eroded by late-Wisconsinan ice, creating streamlined landforms. Eroded bedrock and megafluted ice-contact sediment on the flanks of Grand Manan Basin indicate the southwest direction of topographically-steered ice. 2) Subglacial landsystem II: Along the southern margin of the Bay of Fundy, an array of drumlins, with superimposed esker complexes, was formed by glacial ice that emanated northwest from the interior of Nova Scotia and was deflected to the southwest by the ice flowing out of the Bay of Fundy to the Gulf of Maine. The esker complexes formed later when the Nova Scotia ice sheet stagnated and meltwater escaped northwest via topographic gaps. 3) Ice-marginal landsystem I: In northern Bay of Fundy, both small De Geer moraines and larger, basin-bounding moraines were created when retreating late-Wisconsinan ice became grounded in relatively shallow water. New radiocarbon ages show that the Owen Basin Moraine in this landsystem was abandoned prior to c. 14,600 14C yr BP (cal BP 17,015-17,270 [0.7], 17,286-17,405 [0.3]). 4) Ice-marginal landsystem II: This distinctive landsystem consists of numerous arcuate moraines, commonly superimposed on one another. This landsystem was formed by thin (170 m), lightly grounded ice that retreated northeast into the Bay of Fundy. The splayed pattern of the ice margin was a response to a large

  6. ENVIRONMENTAL IMPACTS IN THE PROCESS OF SOCIAL OWNERSHIP OF SPACE IN THE BAY OF THE PONTAL IN MUNICIPALITY OF ILHÉUS / BA

    Directory of Open Access Journals (Sweden)

    Emilson Batista da Silva

    2014-07-01

    Full Text Available This study is about the relationship between society and nature, considering the impact of the appropriation of space in the estuary of Pontal Bay -Ilhéus/BA. The time frame adopted begins with the 70s and extends until the year 2012. The research approach was qualitative, adopting quantitative techniques when necessary. The instruments of collection consisted of systematic observation and interview, plus documentary and bibliographic research. The analyzes showed evidence that the socio-spatial interventions in the Bay originate from the construction of the Port of Ilheus in the northern portion, from the growing, environmental degradation of river basins tributaries (rivers Cachoeira, Santana and Itacanoeira and from the process of occupation surrounding the Bay. These pressures have caused changes in the dynamics of estuarine circulation, leading to a state of beach progradation, intensifying the process of silting up of the Bay, propension to formation of mangroves and impaired water quality due to discharge of sewage.

  7. Optical ages indicate the southwestern margin of the Green Bay Lobe in Wisconsin, USA, was at its maximum extent until about 18,500 years ago

    Science.gov (United States)

    Attig, J.W.; Hanson, P.R.; Rawling, J.E.; Young, A.R.; Carson, E.C.

    2011-01-01

    Samples for optical dating were collected to estimate the time of sediment deposition in small ice-marginal lakes in the Baraboo Hills of Wisconsin. These lakes formed high in the Baraboo Hills when drainage was blocked by the Green Bay Lobe when it was at or very near its maximum extent. Therefore, these optical ages provide control for the timing of the thinning and recession of the Green Bay Lobe from its maximum position. Sediment that accumulated in four small ice-marginal lakes was sampled and dated. Difficulties with field sampling and estimating dose rates made the interpretation of optical ages derived from samples from two of the lake basins problematic. Samples from the other two lake basins-South Bluff and Feltz basins-responded well during laboratory analysis and showed reasonably good agreement between the multiple ages produced at each site. These ages averaged 18.2. ka (n= 6) and 18.6. ka (n= 6), respectively. The optical ages from these two lake basins where we could carefully select sediment samples provide firm evidence that the Green Bay Lobe stood at or very near its maximum extent until about 18.5. ka.The persistence of ice-marginal lakes in these basins high in the Baraboo Hills indicates that the ice of the Green Bay Lobe had not experienced significant thinning near its margin prior to about 18.5. ka. These ages are the first to directly constrain the timing of the maximum extent of the Green Bay Lobe and the onset of deglaciation in the area for which the Wisconsin Glaciation was named. ?? 2011 Elsevier B.V.

  8. Quantum Annealing for Variational Bayes Inference

    OpenAIRE

    Sato, Issei; Kurihara, Kenichi; Tanaka, Shu; Nakagawa, Hiroshi; Miyashita, Seiji

    2014-01-01

    This paper presents studies on a deterministic annealing algorithm based on quantum annealing for variational Bayes (QAVB) inference, which can be seen as an extension of the simulated annealing for variational Bayes (SAVB) inference. QAVB is as easy as SAVB to implement. Experiments revealed QAVB finds a better local optimum than SAVB in terms of the variational free energy in latent Dirichlet allocation (LDA).

  9. Safety culture development at Daya Bay NPP

    International Nuclear Information System (INIS)

    From view on Organization Behavior theory, the concept, development and affecting factors of safety culture are introduced. The focuses are on the establishment, development and management practice for safety culture at Daya Bay NPP. A strong safety culture, also demonstrated, has contributed greatly to improving performance at Daya Bay

  10. Anthropization in Montevideo Bay during the Holocene

    International Nuclear Information System (INIS)

    This work is about the anthropogenic historic impacts in subtidal environments in Montevideo Bay. The studies carried out in the sediments enable to conclude that the increase of the industrial discharges (nutrients, heavy metals) are the cause of the chemical changes in the sediment of the Montevideo Bay

  11. Mixed layer variability and chlorophyll a biomass in the Bay of Bengal

    Science.gov (United States)

    Narvekar, J.; Prasanna Kumar, S.

    2014-07-01

    The mixed layer is the most variable and dynamically active part of the marine environment that couples the underlying ocean to the atmosphere and plays an important role in determining the oceanic primary productivity. We examined the basin-scale processes controlling the seasonal variability of mixed layer depth in the Bay of Bengal and its association with chlorophyll using a suite of in situ as well as remote sensing data. A coupling between mixed layer depth and chlorophyll was seen during spring intermonsoon and summer monsoon, but for different reasons. In spring intermonsoon the temperature-dominated stratification and associated shallow mixed layer makes the upper waters of the Bay of Bengal nutrient depleted and oligotrophic. In summer, although the salinity-dominated stratification in the northern Bay of Bengal shallows the mixed layer, the nutrient input from adjoining rivers enhance the surface chlorophyll. This enhancement is confined only to the surface layer and with increase in depth, the chlorophyll biomass decreases rapidly due to reduction in sunlight by suspended sediment. In the south, advection of high salinity waters from the Arabian Sea and westward propagating Rossby waves from the eastern Bay of Bengal led to the formation of deep mixed layer. In contrast, in the Indo-Sri Lanka region, the shallow mixed layer and nutrient enrichment driven by upwelling and Ekman pumping resulted in chlorophyll enhancement. The mismatch between the nitrate and chlorophyll indicated the inadequacy of present data to fully unravel its coupling to mixed layer processes.

  12. Bayesian Posteriors Without Bayes' Theorem

    CERN Document Server

    Hill, Theodore P

    2012-01-01

    The classical Bayesian posterior arises naturally as the unique solution of several different optimization problems, without the necessity of interpreting data as conditional probabilities and then using Bayes' Theorem. For example, the classical Bayesian posterior is the unique posterior that minimizes the loss of Shannon information in combining the prior and the likelihood distributions. These results, direct corollaries of recent results about conflations of probability distributions, reinforce the use of Bayesian posteriors, and may help partially reconcile some of the differences between classical and Bayesian statistics.

  13. Juvenile and small resident fishes of Florida Bay, a critical habitat in the Everglades National Park, Florida

    OpenAIRE

    Powell, Allyn B.; Thayer, Gordon; LaCroix, Michael; Cheshire, Robin

    2007-01-01

    This compendium presents information on the life history, diet, and abundance and distribution of 46 of the more abundant juvenile and small resident fish species, and data on three species of seagrasses in Florida Bay, Everglades National Park. Abundance and distribution of fish data were derived from three sampling schemes: (1) an otter trawl in basins (1984–1985, 1994–2001), (2) a surface trawl in basins (1984–1985), and (3) a surface trawl in channels (1984–1985). Results from surfa...

  14. Forecast of Exploration Potential and Reserves Growth in Jiyang Depression

    Institute of Scientific and Technical Information of China (English)

    Yang Wanqin

    2010-01-01

    @@ Jiyang Depression, located in northern Shandong Province, is part of the Bohai Bay Basin of Sino-Korean platform, with the exploration acreage being 35,696square kilometers.It consists of Dongying, Zhanhua,Chezhen, and Huimin sags and the beach area, 73 oil and gas fields have been discovered here.After drilling the first commercial oil flow in Hua-8 well in 1961,exploration in Jiyang Depression has been carried out for 49 years yet.

  15. Transitioning a Chesapeake Bay Ecological Prediction System to Operations

    Science.gov (United States)

    Brown, C.; Green, D. S.; Eco Forecasters

    2011-12-01

    Ecological prediction of the impacts of physical, chemical, biological, and human-induced change on ecosystems and their components, encompass a wide range of space and time scales, and subject matter. They vary from predicting the occurrence and/or transport of certain species, such harmful algal blooms, or biogeochemical constituents, such as dissolved oxygen concentrations, to large-scale ecosystem responses and higher trophic levels. The timescales of ecological prediction, including guidance and forecasts, range from nowcasts and short-term forecasts (days), to intraseasonal and interannual outlooks (weeks to months), to decadal and century projections in climate change scenarios. The spatial scales range from small coastal inlets to basin and global scale biogeochemical and ecological forecasts. The types of models that have been used include conceptual, empirical, mechanistic, and hybrid approaches. This presentation will identify the challenges and progress toward transitioning experimental model-based ecological prediction into operational guidance and forecasting. Recent efforts are targeting integration of regional ocean, hydrodynamic and hydrological models and leveraging weather and water service infrastructure to enable the prototyping of an operational ecological forecast capability for the Chesapeake Bay and its tidal tributaries. A path finder demonstration predicts the probability of encountering sea nettles (Chrysaora quinquecirrha), a stinging jellyfish. These jellyfish can negatively impact safety and economic activities in the bay and an impact-based forecast that predicts where and when this biotic nuisance occurs may help management effects. The issuance of bay-wide nowcasts and three-day forecasts of sea nettle probability are generated daily by forcing an empirical habitat model (that predicts the probability of sea nettles) with real-time and 3-day forecasts of sea-surface temperature (SST) and salinity (SSS). In the first demonstration

  16. The ocean floor morphostructure of the Bay of Bengal (Indian Ocean) and the problem of its origin

    Science.gov (United States)

    Illarionov, V. K.; Boyko, A. N.; Udintsev, G. B.

    2016-05-01

    This study is based on the geological and geophysical data obtained in the Bay of Bengal and adjacent part of the Mid-Indian Ocean Basin by different Russian scientific and industrial institutions in the 1980s and 1990s. The results of the more recent foreign investigations are also involved. The analysis of the collected data provided a new insight into the geological structure and evolution of the region indicating that a large dry-land area—the Bengal elevation—existed in the Cretaceous at the location of the present-day Bay of Bengal. During the Cretaceous, the geological evolution of this area was controlled by epicontinental sedimentation and active volcanism. In the Late Cretaceous, progressive submersion with the inception of the Central Basin took place in the region. The subsidence of the basement was accompanied by active differentiated tectonic movements in the southern part of the Bay of Bengal. As a result, the basement experienced fragmentation into blocks with the formation of horst and graben structures. The horst relics eventually submerged to the current depths in the Late Miocene-Pliocene. The maximal amplitude of basement submersion within the bay is more than 11 km.

  17. Life History, Diet, Abundance and Distribution, and Length-Frequencies of Selected Invertebrates in Florida Bay, Everglades National Park, Florida

    OpenAIRE

    Powell, Allyn B.; LaCroix, Michael W.; Cheshire, Robin T.; Thayer, Gordon W.

    2006-01-01

    This report presents information on the life history, diet, abundance and distribution, and length-frequency distributions of five invertebrates in Florida Bay, Everglades National Park. Collections were made with an otter trawl in basins on a bi-monthly basis. Non-parametric statistics were used to test spatial and temporal differences in the abundance of invertebrates when numbers were appropriate (i. e., $25). Invertebrate species are presented in four sections. The sections on Life H...

  18. Detrital thermochronology and sedimentology of the Sabine Bay and Assistance formations, Ellesmere Island: insights into the source of the Melvilian Disturbance event

    Science.gov (United States)

    Chau, Y.; Leier, A.; Guest, B.; Beauchamp, B.; Morris, N.

    2011-12-01

    The Melvillian Disturbance in the Sverdrup Basin of the Canadian Arctic occurred between early and middle Permian time and is characterized by angular unconfomities, basaltic flows, and is linked to a broader mid-Permian circum-Arctic tectonic event.We examined the lower-middle Permian Sabine Bay and Assistance formations exposed in northwestern Ellesmere Island in order to better understand the depositional and tectonic history of this region during the middle Permian time. Detailed sections of these units were measured at multiple locations and samples were collected for zircon/apatite thermochronology. The Sabine Bay Formation is present in limited locations where it consists of white, medium-grained, quartzose sediments. Beds contain trough cross-strata with drapes of mud-sized organic material, ripples, and rare bioturbation. Preliminary paleocurrent data indicate transport to the west. We interpret the Sabine Bay Formation to have been deposited in a fluvial environment, possibly with some tidal influence. The Assistance Formation unconformably overlies the Sabine Bay Formation and appears to be more regionally extensive than the Sabine Bay Formation. The Assistance Formation consists of fine-grained quartzose sandstone with abundant Zoophycos burrows, shell biota and other marine trace fossils. The character of the Assistance Formation varies between locations, but in some locations the formation contains hummocky and swaley cross-stratification bedding. Vertically, the Assistance Formation grades from sandstone beds into mudstone beds with deeper-water marine trace fossils. We interpret the Assistance Formation to have been deposited in a lower-shoreface, storm-influenced, shelf setting that was progressively transgressed during deposition. The isolated occurrences of the Sabine Bay Formation and large lateral thickness variations of the Assistance Formation suggest these units were deposited in fault-bounded sub-basins within the Sverdrup Basin. The larger

  19. Radioactivity Levels in Kola Bay

    International Nuclear Information System (INIS)

    Sediment samples were collected in May 1995 from 16 locations in Kola Bay, North-west Russia, during an expedition starting from Murmansk and ending at Kildin Island in the Barents Sea. The purpose was to study the contamination level in an area with several potential sources of civilian and military radioactive pollution. 137Cs concentrations in the sediments, algae and benthic samples were low, but small particles containing 137Cs were separated from the sediment samples. All the sediments between the nuclear icebreaker base Atomflot and the open Barents Sea contained 60Co. Traces of 125Sb, 134Cs, 95Zr, 154Eu and 152Eu were also detected in some of the samples. Plutonium levels were low, but the increased 238Pu/239,240Pu ratio at Atomflot indicated a fresh release from the facility or from the waste storage vessels, Lepse and Imandra, lying in front of it. An increased 238Pu/239,240Pu ratio was also found in sediment collected in the outlet of Kola Bay in the Barents Sea. (author)

  20. Paleo ice flow and subglacial meltwater dynamics in Pine Island Bay, West Antarctica

    Directory of Open Access Journals (Sweden)

    F. O. Nitsche

    2013-02-01

    Full Text Available Increasing evidence for an elaborate subglacial drainage network underneath modern Antarctic ice sheets suggests that basal meltwater has an important influence on ice stream flow. Swath bathymetry surveys from previously glaciated continental margins display morphological features indicative of subglacial meltwater flow in inner shelf areas of some paleo ice stream troughs. Over the last few years several expeditions to the eastern Amundsen Sea embayment (West Antarctica have investigated the paleo ice streams that extended from the Pine Island and Thwaites glaciers. A compilation of high-resolution swath bathymetry data from inner Pine Island Bay reveals details of a rough seabed topography including several deep channels that connect a series of basins. This complex basin and channel network is indicative of meltwater flow beneath the paleo-Pine Island and Thwaites ice streams, along with substantial subglacial water inflow from the east. This meltwater could have enhanced ice flow over the rough bedrock topography. Meltwater features diminish with the onset of linear features north of the basins. Similar features have previously been observed in several other areas, including the Dotson-Getz Trough (western Amundsen Sea embayment and Marguerite Bay (SW Antarctic Peninsula, suggesting that these features may be widespread around the Antarctic margin and that subglacial meltwater drainage played a major role in past ice-sheet dynamics.

  1. Paleo ice flow and subglacial meltwater dynamics in Pine Island Bay, West Antarctica

    Directory of Open Access Journals (Sweden)

    F. O. Nitsche

    2012-10-01

    Full Text Available Increasing evidence for an elaborate subglacial drainage network underneath modern Antarctic ice sheets suggests that basal meltwater has an important influence on ice stream flow. Swath bathymetry surveys from previously glaciated continental margins display morphological features indicative of subglacial meltwater flow in inner shelf areas of some paleo ice stream troughs. Over the last few years several expeditions to the Eastern Amundsen Sea embayment (West Antarctica have investigated the paleo ice streams that extended from the Pine Island and Thwaites glaciers. A compilation of high-resolution swath bathymetry data from inner Pine Island Bay reveals details of a rough seabed topography including several deep channels that connect a series of basins. This complex basin and channel network is indicative of meltwater flow beneath the paleo-Pine Island and Thwaites ice streams, along with substantial subglacial water inflow from the east. This meltwater could have enhanced ice flow over the rough bedrock topography. Meltwater features diminish with the onset of linear features north of the basins. Similar features have previously been observed in several other areas, including the Dotson-Getz Trough (Western Amundsen Sea embayment and Marguerite Bay (SW Antarctic Peninsula, suggesting that these features may be widespread around the Antarctic margin and that subglacial meltwater drainage played a major role in past ice-sheet dynamics.

  2. Origins of High H2S-bearing Natural Gas in China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Natural gas containing hydrogen sulphide (H2S) has been found in several petroliferous basins in China, such as the Sichuan Basin, Bohai Bay Basin, Ordos Basin, Tarim Basin, etc. Natural gas with higher H2S contents (H2S >5% mol.) is mostly distributed in both the gas reservoirs of Dukouhe, Luojiazhai, Puguang and Tieshanpo, which belong to the Triassic Feixianguan Formation in the northeastern Sichuan Basin and those of the Kongdian-Shahejie formations in the northeastern Jinxian Sag of the Jizhong Depression, Bohai Bay Basin. In the Sichuan Basin, the H2S contents of natural gas average over 9% and some can be 17 %, while those of the Bohai Bay Basin range from 40 % to 92 %, being then one of the gas reservoirs with the highest H2S contents in the world. Based on detailed observation and sample analysis results of a total 5000 m of core from over 70 wells in the above-mentioned two basins, especially sulfur isotopic analysis of gypsum,brimstone, pyrite and natural gas, also with integrated study of the geochemical characteristics of hydrocarbons, it is thought that the natural gas with high H2S contents resulted from thermochemical sulfate reduction (TSR) reactions.Among them, the natural gas in the Feixianguan Formation resulted from TSR reactions participated by hydrocarbon gas,while that in the Zhaolanzhuang of the Jinxian Sag being the product of TSR participated by crude oil. During the consumption process of hydrocarbons due to TSR, the heavy hydrocarbons were apt to react with sulfate, which accordingly resulted in the dry coefficient of natural gas increasing and the carbon isotopes becoming heavier.

  3. Zinc and Its Isotopes in the Loire River Basin, France

    Science.gov (United States)

    Millot, R.; Desaulty, A. M.; Bourrain, X.

    2014-12-01

    The contribution of human activities such as industries, agriculture and domestic inputs, becomes more and more significant in the chemical composition of the dissolved load of rivers. Human factors act as a supplementary key process. Therefore the mass-balance for the budget of catchments and river basins include anthropogenic disturbances. The Loire River in central France is approximately 1010 km long and drains an area of 117,800 km2. In the upper basin, the bedrock is old plutonic rock overlain by much younger volcanic rocks. The intermediate basin includes three major tributaries flowing into the Loire River from the left bank: the Cher, the Indre and the Vienne rivers; the main stream flows westward and its valley stretches toward the Atlantic Ocean. Here, the Loire River drains the sedimentary series of the Paris Basin, mainly carbonate deposits. The lower Loire basin drains pre-Mesozoic basement of the Armorican Massif and its overlying Mesozoic to Cenozoic sedimentary deposits. The Loire River is one of the main European riverine inputs to the Atlantic ocean. Here we are reporting concentration and isotope data for Zn in river waters and suspended sediments from the Loire River Basin. In addition, we also report concentration and isotope data for the different industrial sources within the Loire Basin, as well as data for biota samples such as mussels and oysters from the Bay of Biscay and North Brittany. These organisms are known to be natural accumulators of metal pollutants. Zinc isotopic compositions are rather homogeneous in river waters with δ66Zn values ranging from 0.21 to 0.39‰. This range of variation is very different from anthropogenic signature (industrial and/or agriculture release) that displays δ66Zn values between 0.02 to 0.14‰. This result is in agreement with a geogenic origin and the low Zn concentrations in the Loire River Basin (from 0.8 to 6 µg/L).

  4. Functional groups of fish assemblages and their major species in the Bohai Sea%渤海鱼类群落功能群及其主要种类

    Institute of Scientific and Technical Information of China (English)

    张波; 李忠义; 金显仕

    2012-01-01

    根据2009年8月和10月对渤海渔业资源的底拖网调查,采用胃含物分析、聚类分析和功能群划分的方法研究了渤海鱼类群落的功能群组成及其主要种类.结果表明,渤海夏、秋季鱼类群落包括7个功能群,分别为浮游动物食性功能群、杂食性功能群、底栖动物食性功能群、虾食性功能群、虾/鱼食性功能群、鱼食性功能群和广食性功能群;其中主要功能群为浮游动物食性功能群、杂食性功能群和虾/鱼食性功能群;主要种类有小黄鱼、蓝点马鲛、斑(鱼祭)、赤鼻棱鳀、银鲳和黄鲫.圆筛藻、中华哲水蚤、太平洋磷虾、长额刺糠虾、中国毛虾、甲壳类幼体、日本鼓虾、六丝矛尾(鱼段)虎鱼、小黄鱼、双壳类和腹足类是当前渤海夏、秋季鱼类群落的主要饵料种类.%The Bohai Sea is a semi-enclosed shallow sea and is an important spawning,nursery and feeding ground for many migratory species from the Yellow Sea. Currently, overfishing and environment degradation may have changed the community structure in the Bohai Sea. The decline in the biomass, species composition, and size spectrum indicates a degradation of the Bohai Sea ecosystem. At the same time, the mean trophic level at high trophic level declined faster than global trend. So, it is very necessary to re-understand the feeding relationship in the Bohai Sea. Based on the data collected from bottom trawl surveys conducted in August and October of 2009 in the Bohai Sea,23 kinds of fish species, not including silver pomfret Pampus argenteus, and 7263 stomach samples were analyed. According to stomach analysis, the cluster analysis, of which 60% of similarity level was used as criterion, was used to study the functional groups and their major species of fish assemblages in the Bohai Sea. The results suggested that seven functional groups were divided among fish assemblages in the Bohai Sea,that is zooplantivores

  5. Practices of Drilling Integration Management in Bohai Oilifeld%海上油田随钻一体化管理探索与实践

    Institute of Scientific and Technical Information of China (English)

    赵国权; 王国栋; 谭吕

    2015-01-01

    随着渤海油田发展规模不断扩大,为了提升油田管理效率,实现油田开发效益最大化,在油田随钻管理中,设立随钻核心区、设立随钻目标、建立联动机制、设立实施标准,创立了“研究作业一体化”、“钻井建造一体化”、“实施调整一体化”、“在建生产一体化”为特点的多专业一体化管理体制,采用技术、管理双轮驱动的管理模式实施开发建设管理,经渤海湾多油田开发实践取得成功,实施一体化管理模式适合海上油田随钻项目管理,可以有效提升油田开发项目的管理水平、建设质量及经济效益。%As development of Bohai Oilifeld is accelerated, it is necessary to establish the key drilling zone and drilling targets, interrelated mechanism, and execution standards to boost oilifeld management efifciency and maximize development performance. Therefore, an integration management system is put in place, covering “integration of research and service,” “integration of drilling and building,” “integration of implementation and adjustment,” and “integration of construction and production.” The management pattern driven by both technology and management has been successful in construction and development of Bohai Oilifeld in the past years. This integrated management pattern is appropriate for drilling project of offshore oilifelds, effectively boosting management level, construction quality and economic performance of offshore oilifeld development projects.

  6. 46 CFR 7.20 - Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island Sound and...

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island Sound and easterly entrance to Long Island Sound, NY. 7.20 Section 7.20... Atlantic Coast § 7.20 Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block...

  7. A Tidally Averaged Sediment-Transport Model for San Francisco Bay, California

    Science.gov (United States)

    Lionberger, Megan A.; Schoellhamer, David H.

    2009-01-01

    A tidally averaged sediment-transport model of San Francisco Bay was incorporated into a tidally averaged salinity box model previously developed and calibrated using salinity, a conservative tracer (Uncles and Peterson, 1995; Knowles, 1996). The Bay is represented in the model by 50 segments composed of two layers: one representing the channel (>5-meter depth) and the other the shallows (0- to 5-meter depth). Calculations are made using a daily time step and simulations can be made on the decadal time scale. The sediment-transport model includes an erosion-deposition algorithm, a bed-sediment algorithm, and sediment boundary conditions. Erosion and deposition of bed sediments are calculated explicitly, and suspended sediment is transported by implicitly solving the advection-dispersion equation. The bed-sediment model simulates the increase in bed strength with depth, owing to consolidation of fine sediments that make up San Francisco Bay mud. The model is calibrated to either net sedimentation calculated from bathymetric-change data or measured suspended-sediment concentration. Specified boundary conditions are the tributary fluxes of suspended sediment and suspended-sediment concentration in the Pacific Ocean. Results of model calibration and validation show that the model simulates the trends in suspended-sediment concentration associated with tidal fluctuations, residual velocity, and wind stress well, although the spring neap tidal suspended-sediment concentration variability was consistently underestimated. Model validation also showed poor simulation of seasonal sediment pulses from the Sacramento-San Joaquin River Delta at Point San Pablo because the pulses enter the Bay over only a few days and the fate of the pulses is determined by intra-tidal deposition and resuspension that are not included in this tidally averaged model. The model was calibrated to net-basin sedimentation to calculate budgets of sediment and sediment-associated contaminants. While

  8. Persistent whole-bay red tide of Noctiluca scintillans in Manila Bay, Philippines

    OpenAIRE

    Furuya, Ken; Saito, Haruna; Rujinard, Sriwoon; Anil K. Vijayan; Omura, Takuo; Elsa E. Furio; Valeriano M. Borja; Sopana, Boonyapiwat; Thaithaworn, Lirdwitayaprasit

    2006-01-01

    Noctiluca scintillans, which contains a photosynthetic endosymbiont, Pedinomonas noctilucae, formed perennial red tides in Manila Bay, Philippines, occasionally covering almost whole area since 2001. A whole-bay scale red tide of the green Noctiluca in Manila Bay is described as the first step to elucidate the formation mechanism of the large scale blooming of the organism. A field survey was conducted in March 2004, when greenish discoloration due to N. scintillans was observed in the whole ...

  9. Holy grail at Baglan Bay

    Energy Technology Data Exchange (ETDEWEB)

    Watson, Jim

    1999-09-01

    The UK government's consent for the construction of a gas-fired power plant at Baglan Bay in South Wales is reported, and the growing popularity of economic combined-cycle gas turbine (CCGT) power plants and the resulting environmental improvements are noted . The combining of gas and steam turbines, design developments, and the UK moratorium on planning consents for gas fired power plants are discussed. General Electric's H System technology which will lower the amount of energy lost in the conversion of natural gas to electricity is described, and details of the ten most problematic CCGTs in the UK are given. The domination of the CCGT global market by four manufacturers, and the pressure on manufacturers to develop their designs are considered. (UK)

  10. Bayes linear covariance matrix adjustment

    CERN Document Server

    Wilkinson, Darren J

    1995-01-01

    In this thesis, a Bayes linear methodology for the adjustment of covariance matrices is presented and discussed. A geometric framework for quantifying uncertainties about covariance matrices is set up, and an inner-product for spaces of random matrices is motivated and constructed. The inner-product on this space captures aspects of our beliefs about the relationship between covariance matrices of interest to us, providing a structure rich enough for us to adjust beliefs about unknown matrices in the light of data such as sample covariance matrices, exploiting second-order exchangeability and related specifications to obtain representations allowing analysis. Adjustment is associated with orthogonal projection, and illustrated with examples of adjustments for some common problems. The problem of adjusting the covariance matrices underlying exchangeable random vectors is tackled and discussed. Learning about the covariance matrices associated with multivariate time series dynamic linear models is shown to be a...

  11. Why is the Bay of Bengal less productive during summer monsoon compared to the Arabian Sea?

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Muraleedharan, P.M.; Prasad, T.G.; Gauns, M.; Ramaiah, N.; DeSouza, S.N.; Sardessai, S.; Madhupratap, M.

    . 1. Introduction The Bay of Bengal in the eastern part of the north Indian Ocean is a tropical basin. Like its western counterpart, the Arabian Sea, it is land locked in the north and forced by seasonally reversing monsoon winds. Accordingly... summer data of two different years, is based on the fact that though semi-annual switching of the winds may have inter-annual variability, on the whole, the summer monsoon is a highly regular phenomenon [Fieux and Stommel, 1977]. 3. Results...

  12. The Liverpool Bay Coastal Observatory

    Science.gov (United States)

    Howarth, John; Palmer, Matthew

    2011-11-01

    A pilot Coastal Observatory has been established in Liverpool Bay which integrates (near) real-time measurements with coupled models and whose results are displayed on the web. The aim is to understand the functioning of coastal seas, their response to natural forcing and the consequences of human activity. The eastern Irish Sea is an apt test site, since it encompasses a comprehensive range of processes found in tidally dominated coastal seas, including near-shore physical and biogeochemical processes influenced by estuarine inflows, where both vertical and horizontal gradients are important. Applications include hypernutrification, since the region receives significantly elevated levels of nutrient inputs, shoreline management (coastal flooding and beach erosion/accretion), and understanding present conditions to predict the impact of climate change (for instance if the number and severity of storms, or of high or low river flows, change). The integrated measurement suite which started in August 2002 covers a range of space and time scales. It includes in situ time series, four to six weekly regional water column surveys, an instrumented ferry, a shore-based HF radar system measuring surface currents and waves, coastal tide gauges and visible and infra-red satellite data. The time series enable definition of the seasonal cycle, its inter-annual variability and provide a baseline from which the relative importance of events can be quantified. A suite of nested 3D hydrodynamic, wave and ecosystem models is run daily, focusing on the observatory area by covering the ocean/shelf of northwest Europe (at 12-km resolution) and the Irish Sea (at 1.8 km), and Liverpool Bay at the highest resolution of 200 m. The measurements test the models against events as they happen in a truly 3D context. All measurements and model outputs are displayed freely on the Coastal Observatory website (http://cobs.pol.ac.uk) for an audience of researchers, education, coastal managers and the

  13. The structure and stratigraphy of the sedimentary succession in the Swedish sector of the Baltic Basin: New insights from vintage 2D marine seismic data

    Science.gov (United States)

    Sopher, Daniel; Erlström, Mikael; Bell, Nicholas; Juhlin, Christopher

    2016-04-01

    We present five interpreted regional seismic profiles, describing the full sedimentary sequence across the Swedish sector of the Baltic Sea. The data for the study are part of an extensive and largely unpublished 2D seismic dataset acquired between 1970 and 1990 by the Swedish Oil Prospecting Company (OPAB). The Baltic Basin is an intracratonic basin located in northern Europe. Most of the Swedish sector of the basin constitutes the NW flank of a broad synclinal depression, the Baltic Basin. In the SW of the Swedish sector lies the Hanö Bay Basin, formed by subsidence associated with inversion of the Tornquist Zone during the Late Cretaceous. The geological history presented here is broadly consistent with previously published works. We observe an area between the Hanö Bay and the Baltic Basin where the Palaeozoic strata has been affected by transpression and subsequent inversion, associated with the Tornquist Zone during the late Carboniferous-Early Permian and Late Cretaceous, respectively. We propose that the Christiansø High was a structural low during the Late Jurassic, which was later inverted in the Late Cretaceous. We suggest that a fan shaped feature in the seismic data, adjacent to the Christiansø Fault within the Hanö Bay Basin, represents rapidly deposited, coarse-grained sediments eroded from the inverted Christiansø High during the Late Cretaceous. We identify a number of faults within the deeper part of the Baltic Basin, which we also interpret to be transpressional in nature, formed during the Caledonian Orogeny in the Late Silurian-Early Devonian. East of Gotland a number of sedimentary structures consisting of Silurian carbonate reefs and Ordovician carbonate mounds, as well as a large Quaternary glacial feature are observed. Finally, we use the seismic interpretation to infer the structural and stratigraphic history of the Baltic and Hanö Bay basins within the Swedish sector.

  14. Origin of ash in the Central Indian Ocean Basin and its implication for the volume estimate of the 74,000 year BP Youngest Toba eruption

    Digital Repository Service at National Institute of Oceanography (India)

    Pattan, J.N.; Pearce, N.J.G.; Banakar, V.K.; Parthiban, G.

    .86) 4.22 (0 .33) ? 4.94 N 91 274 72 53 16 1, Central Indian Ocean Basin 7 (present study); 2, YTT from Sum a tra, Malaysia, Bay of Bengal and India 10 ; 3, YTT from the Indian subcont i- nent 15 ; 4, YTT from....4 7.5 6.6 5.9 6.9 6.9 5.1 5.8 6.5 1, Central Indian Ocean Basin (pr esent study, n = 8); 2, YTT from Sumatra, Malaysia, ODP site 758, Bay of Bengal and India 10 ( n...

  15. Hydrocarbon accumulation process of large scale oil and gas field of granite buried hill in Penglai 9-1 structure,Bohai,China%蓬莱9-1构造花岗岩古潜山大型油气田的成藏过程

    Institute of Scientific and Technical Information of China (English)

    徐国盛; 陈飞; 周兴怀; 王昕; 李建平; 王国芝; 王霄; 范蕾

    2016-01-01

    目前国内针对燕山运动期中生代侵入的花岗岩潜山油气如何成藏且成藏规模之大的研究非常匮乏。该文主要采用岩心观察、薄片鉴定、指纹化石对比及油气盆地模拟等方法,对渤海海域蓬莱9-1构造花岗岩潜山的储层特征、油源对比及成藏条件进行了详细剖析,恢复了渤海蓬莱9-1构造花岗岩古潜山大型油气田的成藏过程,并建立成藏模式。根据花岗岩风化壳的风化程度,自上而下分为:砂-砾质风化带、裂缝带与基岩带,主要储集空间为溶蚀孔隙与微裂缝,风化壳储层发育厚度几十米,甚至达200多米。古潜山油源来自渤东南洼沙三段、沙一段或东营组烃源岩。储层发育区主要分布于风化壳的高部位,新近系馆陶组是潜山油藏有利的封堵层。古潜山油藏具有“下生上储顶盖的新生古储式组合”和“高压驱烃、断层不整合输导、油气仓储式成藏”的特点。%The granite buried hill weathering crust reservoir of Penglai 9-1 on the bulge of Miaoxibei in Bohai is a large scale oil and gas field firstly discovered in offshore China.However,the mechanism of hydrocarbon accumulation in granite buried hill in such a large-scale oilfield during the Yanshan movement is rarely studied. Therefore, different methods of core observation, thin section identification,fingerprint fossil comparison and hydrocarbon basin simulation are used to analyze the reservoir characteristics of granite buried hill,oil and source rock correlation and conditions of hydrocarbon accumulation,so as to restore the hydrocarbon accumulation process and construct the accumulation mode of Penglai 9-1 structure. According to the extent of weathering, granite weathering crust is divided from top to bottom into three parts:sand-gravel weathered zone,fracture zone and the bedrock zone respectively.The thickness of weathering crust varies from several tens of meters to even more

  16. Historical methyl mercury in San Francisco Bay

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — San Francisco Bay, California is considered a mercury-impaired watershed. Elevated concentrations of mercury are found in water and sediment as well as fish and...

  17. FL BAY SPECTROUT-POPULATION STATUS

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Juvenile spotted seatrout and other sportfish are being monitored annually over a 6-mo period in Florida Bay to assess their abundance over time relative to...

  18. South Bay Salt Ponds : Initial stewardship plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The California Department of Fish and Game and the U.S. Fish and Wildlife Service will operate and maintain the South Bay Salt Ponds under this Initial Stewardship...

  19. 2004 Saginaw Bay, Lake Huron, Michigan Lidar

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This metadata document describes the collection and processing of Light Detection and Ranging (LIDAR) data over an area along the coast of Saginaw Bay, Lake Huron,...

  20. Delaware River and Upper Bay Sediment Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The area of coverage consists of 192 square miles of benthic habitat mapped from 2005 to 2007 in the Delaware River and Upper Delaware Bay. The bottom sediment map...

  1. On Bayes' theorem for improper mixtures

    CERN Document Server

    McCullagh, Peter; 10.1214/11-AOS892

    2011-01-01

    Although Bayes's theorem demands a prior that is a probability distribution on the parameter space, the calculus associated with Bayes's theorem sometimes generates sensible procedures from improper priors, Pitman's estimator being a good example. However, improper priors may also lead to Bayes procedures that are paradoxical or otherwise unsatisfactory, prompting some authors to insist that all priors be proper. This paper begins with the observation that an improper measure on Theta satisfying Kingman's countability condition is in fact a probability distribution on the power set. We show how to extend a model in such a way that the extended parameter space is the power set. Under an additional finiteness condition, which is needed for the existence of a sampling region, the conditions for Bayes's theorem are satisfied by the extension. Lack of interference ensures that the posterior distribution in the extended space is compatible with the original parameter space. Provided that the key finiteness conditio...

  2. BENTHIC MACROFAUNAL ALIENS IN WILLAPA BAY

    Science.gov (United States)

    Benthic macrofaunal samples were collected at random stations in Willapa Bay, WA, in four habitats [eelgrass (Zostera marina), Atlantic cordgrass (Spartina alterniflora), mud shrimp (Upogebia pugettensis), ghost shrimp (Neotrypaea californiensis)] in 1996 and in seven habitats (Z...

  3. Underwater Video Transects in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of Jobos Bay, Puerto Rico were mapped and characterized using visual interpretation...

  4. Underwater Video Sites in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of Jobos Bay, Puerto Rico were mapped and characterized using visual interpretation...

  5. Hydrogeomorphic Regions in the Chesapeake Bay Watershed.

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Generalized lithology (rock type) and physiography based on geologic formations were used to characterize hydrgeomorphic regions (HGMR) within the Chesapeake Bay...

  6. Sediments of Buzzards Bay, MA (HOUGH40)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The modern sediments of Buzzards Bay are described principally by the use of quantitative data from mechanical analyses. The environment of the sediment and its...

  7. A Bayes but Not Classically Sufficient Statistic

    OpenAIRE

    Blackwell, D.; Ramamoorthi, R. V.

    1982-01-01

    In a Borel setting, every classically sufficient statistic is Bayes sufficient, but not vice versa. The example is a hypothesis testing problem in which Bayesians, but not classicists, can achieve zero error probabilities.

  8. Back Bay National Wildlife Refuge: Master Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Back Bay National Wildlife Refuge, located in the city of Virginia Beach, Virginia, comprises 4,608 acres of barrier beach, fresh and brackish marsh, small...

  9. Biscayne Bay Florida Bottlenose Dolphin Studies

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data sets include a compilation of small vessel based studies of bottlenose dolphins that reside within Biscayne Bay, Florida, adjacent estuaries and...

  10. Pb distribution and translocation in Jiaozhou Bay

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The trends of distribution, translocation and seasonal change of heavy metal Pb were studied based on the surface and bottom water sampling in Jiaozhou Bay in 1979, and compared with those in 1990's. The results showed that the source of Pb in the bay was from wastewater and sewage in the east of Jiaozhou Bay from ocean vessels. Pb concentration was higher in spring and lower in summer and autumn, and remained stable through sedimentation in the bottom layer. The overall water quality was good in 1970's. Compared with the environmental monitoring data of 1995-1999, Pb pollution had become serious. Therefore, more efforts should be made to protect the bay from Pb pollution.

  11. Back Bay Wilderness study : Public hearing analysis

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is an analysis of the public hearing that took place on May 15th, 1974 which discussed the Back Bay Wilderness. The analysis shows that there is...

  12. Back Bay Stormwater Monitoring Project Final Report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The objective of this project was to assess the influx of nutrients and solid material into Back Bay and its tributaries during and immediately following such storm...

  13. Back Bay National Wildlife Refuge regulations

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a collection of regulations pertaining to the Back Bay National Wildlife Refuge. Most of the regulations concern motor vehicle use on the refuge.

  14. Back Bay Wilderness study : Proposed recommendations

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a list of recommendations for the proposed wilderness area on the Back Bay National Wildlife Refuge. The recommendations come as a result of the...

  15. Corpus ChristiEast Matagorda Bay 1986

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Patterns of habitat utilization were compared among transplanted and natural Spartina alterniflora marshes in the Halls Lake area of Chocolate Bay in the Galveston...

  16. How to Keep Bug Bites At Bay

    Science.gov (United States)

    ... gov/news/fullstory_160047.html How to Keep Bug Bites at Bay CDC offers advice on thwarting ... 23, 2016 SATURDAY, July 23, 2016 (HealthDay News) -- Bug bites can make you more than itchy. Ticks, ...

  17. Mercury distribution in the Jiaozhou Bay

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Jiaozhou Bay is a semi-enclosed bay, Qingdao, China. More than 10 rivers enter the bay, of which most take wastes from industrial and household discharges. According to historical seasonal investigations in May, August, November 1979, the content,distribution, and development of heavy metal mercury are analyzed as a historical reference. Water samples were taken from the surface and bottom. The results revealed clear seasonal and regional changes in both horizontal and vertical directions, and close relation with major discharging rivers and plankton production. The seawater was polluted more seriously in spring than in any other seasons.However, it was the cleanest in winter during which least waste was input with low plankton production. According to historical data,the state of mercury pollution in seawater was worsening in the period, and has been improving in recent years. Terrestrial contamination was the main reason for mercury pollution in the bay.

  18. Habitat--Drakes Bay and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Drakes Bay and Vicinity map area, California. The vector data file is included in...

  19. Willapa Bay, Washington Benthic Habitats 1995 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...

  20. Willapa Bay, Washington Benthic Habitats 1995 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In June 1995, the Columbia River Estuary Study Taskforce (CREST) acquired 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the State of...