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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. 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.

  4. Sedimentary basin analysis using airborne gravity data: a case study from the Bohai Bay Basin, China

    Science.gov (United States)

    Li, Wenyong; Liu, Yanxu; Zhou, Jianxin; Zhou, Xihua; Li, Bing

    2015-12-01

    In this paper, we discuss the application of an airborne gravity survey to sedimentary basin analysis. Using high-precision airborne gravity data constrained by drilling and seismic data from the Bohai Bay Basin in eastern China, we interpreted faults, structural elements, sedimentary thickness, structural styles and local structures (belts) in the central area of the Basin by the wavelet transform method. Subsequently, these data were subtracted from the Bouguer gravity to calculate the residual gravity anomalies. On this basis, the faults were interpreted mainly by linear zones of high gravity gradients and contour distortion, while the sedimentary thicknesses were computed by the Euler deconvolution. The structural styles were identified by the combination of gravity anomalies and the local structures interpreted by the first vertical derivative of the residual gravity. The results showed evidence for seven faults, one sag and ten new local structure belts.

  5. 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.

  6. 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.

  7. 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:

  8. 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

  9. 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.

  10. 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 Pilong; LI Xue; BAI Guoping

    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.

  11. 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.

  12. 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.

  13. 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.

  14. Geochemistry of a continental saline aquifer for CO2 sequestration: The Guantao formation in the Bohai Bay Basin, North China

    International Nuclear Information System (INIS)

    The Neogene Guantao formation in the Beitang sag in the Bohai Bay Basin (BBB) of North China, a Mesozoic–Cenozoic sedimentary basin of continental origin, has been chosen as a candidate for a pilot field test of CO2 sequestration. Hydrogeological and geochemical investigations have been carried out to assess its suitability, taking advantage of many existing geothermal wells drilled to 2000 m or greater depths. Water samples from 25 wells and drill cores of three sections of the Guantao formation were collected for measurements of mineralogy, water chemistry and isotopes (δ18O, δD, δ13C, 14C). Formation temperature estimated by chemical geothermometry is in the range of 60–80 °C. Geochemical modeling of water–rock–CO2 interaction predicts a strong geochemical response to CO2 injection. Besides the elevated porosity (33.6–38.7%) and high permeability (1150–1980 mD) of the Ng-III formation and a favorable reservoir–caprock combination, it is also found that the formation contains carbonates that will react with CO2 after injection. The low salinity (TDS 2 solubility. The 14C age of the formation water indicates a quasi-closed saline aquifer system over large time scales, the lateral sealing mechanism for CO2 sequestration requires further investigation. The CO2 storage capacity of the Guantao formation within the Beitang sag is estimated to be 17.03 Mt, assuming pure solubility trapping.

  15. 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

  16. Source rock palaeoenvironments and controls on the distribution of dibenzothiophenes in lacustrine crude oils, Bohai Bay Basin, eastern China

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Haiping; Pearson, M.J. [Aberdeen Univ. (United Kingdom). Dept. of Geology and Petroleum Geology

    1999-07-01

    The applicability of sulphur aromatic parameters, based on ratios of dibenzothiophene (DBT) and its alkylated homologues, as indicators of oil maturity has been investigated in 27 oils from the Damintun and Zhuanhua Depressions, Bohai Bay Basin. The oils were characterised by bulk composition and environmentally-sensitive aliphatic biomarkers and were derived from a wide range of lacustrine source depositional environments ranging from highly reducing hypersaline (sulphur-rich oils) to terrestrial input-dominated freshwater (very high wax oils) with maturities ranging from immature to probable mid-mature. Dibenzothiophene-based maturity parameters are not well-correlated with sterane isomerization ratios, and immature oils, in particular, could not be discriminated by these aromatic maturity indicators. In contrast, DBT-based parameters are strongly-correlated with pristane to phytane and Ts/Tm ratios. High methyldibenzothiophene ratios (MDR) are associated with fresh water source deposition whilst low MDRs are found in oils of hypersaline source affinity. Unusually high relative concentrations of 2+3-MDBT were observed in some of the immature oils inferred to be sourced by lacustrine organic laminites. The data provide further evidence that thermal stress is not the sole factor controlling the distribution patterns of dibenzothiophenes in oils and that source depositional environments can exert a dominant influence when their range of variation is large. Absence of DBT in some biodegraded oils is tentatively attributed to its aqueous solubility during associated water washing. (author)

  17. 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.

  18. Subsurface lacustrine storm-seiche depositional model in the Eocene Lijin Sag of the Bohai Bay Basin, East China

    Science.gov (United States)

    Wang, Junhui; Jiang, Zaixing; Zhang, Yuanfu

    2015-10-01

    Recent progress in facies analysis helps to discriminate storm-induced deposits based on interpretation of sedimentary records of combination of oscillatory and unidirectional flows. Located in the southeastern corner of the Bohai Bay Basin in East China, the Lijin Sag is a NE-SW trending Cenozoic half-graben basin. Part of its Eocene deposits (Bindong deposits), which are deposited far away from a contemporary shoreline, consists of thin bedded fine-sandstones and siltstones, interlayed with dark-gray mudstones. New data from drilling wells permit an interpretation of the sedimentary facies. Based on seismic data, well log data, core data and thin-section analyses, storm-dominated deposits were recognized. Petrologic analysis shows that these deposits mainly consist of fine sand- to silt-sized lithic arkose. Detailed sedimentological analyses on lithofacies were conducted to address flowtypes dominant during their geneses. The beds are normal graded and contain Bouma-like sequences. The typical and complete sedimentary sequence consists of fining-upwards successions from an erosive base, followed by gravity flow-induced massive or faint laminated bed or soft sediment deformation structures and unidirectional-combined-oscillatory flow induced beddings, which are attributed to storm wave and seiche processes. From proximal to distal in plane, the Bindong storm deposits exhibit different lithofacies associations and sedimentary processes, i.e., the proximal facies is coarser and dominated by gravity flows, unidirectional flows and combined flows, and formed under strong hydrodynamic conditions; the transitional facies is formed under full range of flow regimes exhibiting a complete Bouma-like sequence; while the distal facies is dominated by gravity flows and pure unidirectional flows without influence of waves. During the deposition period of the Bindong deposits, the paleo-environmental characteristics, such as paleogeographic position, paleoclimate, provenance

  19. 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.

  20. A new method for recovering paleoporosity of sandstone: case study of middle Es3 member of Paleogene formation in Niuzhuang Sag, Dongying Depression, Bohai Bay Basin in China

    Science.gov (United States)

    Liu, Mingjie; Liu, Zhen; Wang, Biao; Sun, Xiaoming; Guo, Jigang

    2015-09-01

    This paper presents a new method for recovering paleoporosity of sandstone reservoirs and quantitatively defines the evolution process of porosity. This method is based on the principle that the present is the key to the past. We take the middle Es3 member in Niuzhuang Sag, Dongying Depression, and Bohai Bay Basin as an example. The method used in this study considers the present porosity as a constraint condition, and the influences of both constructive diagenesis and destructive diagenesis to divide the porosity evolution process into two independent processes, namely porosity increase and porosity decrease. An evolution model of sandstone porosity can be established by combining both the pore increase and pore decrease effects. Our study reveals that the porosity decrease model is a continuous function of burial depth and burial time, whereas the porosity increase model mainly occurs in an acidified window for paleotemperature of 70°C to 90°C. The porosity evolution process can be divided into the following phases: normal compaction, acidification and pore increase, and post-acidification compaction. Thus, the porosity evolution model becomes a piecewise function of three subsections. Examples show that the method can be applied effectively in recovering the paleoporosity of sandstone reservoirs and simulating the porosity evolution process.

  1. 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

  2. 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.

  3. 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

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Occurrence and distribution of antibiotics in coastal water of the Bohai Bay, China: Impacts of river discharge and aquaculture activities

    International Nuclear Information System (INIS)

    The presence of 21 antibiotics in six different groups was investigated in coastal water of the Bohai Bay. Meantime, to illuminate the potential effects caused by the river discharge and aquaculture activities, wastewater from three breeding plants and surface water from six rivers flowing into the Bohai Bay were also analyzed for the selected antibiotics. The result revealed that measured antibiotics in the North Bobai Bay were generally higher than those in the South, highlighting the remarkable effects of high density of human activities on the exposure of antibiotics in environment. The antibiotics found in the six rivers were generally higher than those in the Bohai Bay reflecting the important antibiotics source of river discharge. This study reveals that the high consumption of some antibiotics in aquaculture activities may pose high ecological risk to the bay. - Highlights: → Some antibiotics were ubiquitous with high concentration in the Bohai bay, North China. → The antibiotics were mainly from the six rivers discharge around the Bay. → Antibiotics are commonly used in aquaculture activities around the Bay. → Aquaculture was suggested to be an important antibiotics source in the Bay. - River discharge and aquaculture were suggested to be important sources for antibiotics occurred in the coastal water of the Bohai Bay, North China.

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

    Institute of Scientific and Technical Information of China (English)

    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

  12. 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.

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

    Science.gov (United States)

    Ning-jing, Hu; Peng, Huang; Hui, Zhang; Ai-mei, Zhu; Ji-hua, Liu; Jun, Zhang; Lian-hua, He

    2015-10-01

    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.

  14. 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.

  15. Twin screw multiphase pumps for Bohai Bay offshore applications; Multiphase pumps

    Energy Technology Data Exchange (ETDEWEB)

    Schroener, Hans Juergen

    2010-07-01

    Twin screw multiphase pumps have been installed on offshore platforms in Bohai Bay since 1997. Compared to the operation of a conventional system, the twin screw multiphase pumps offer several advantages, such as: transfer pump and natural gas compressor as well as separate flow lines were eliminated; only one subsea pipeline was used to boost the multiphase fluid to the well head platform; reduced investment because a gas dewatering facility was not required. (AG)

  16. 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.

  17. 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...

  18. 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

  19. 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

  20. 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.

  1. 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.

  2. 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...

  3. 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

  4. New residence times of the Holocene reworked shells on the west coast of Bohai Bay, China

    Science.gov (United States)

    Shang, Zhiwen; Wang, Fu; Li, Jianfen; Marshall, William A.; Chen, Yongsheng; Jiang, Xingyu; Tian, Lizhu; Wang, Hong

    2016-01-01

    Shelly cheniers and shell-rich beds found intercalated in near-shore marine muds and sandy sediments can be used to indicate the location of ancient shorelines, and help to estimate the height of sea level. However, dating the deposition of material within cheniers and shell-rich beds is not straightforward because much of this material is transported and re-worked, creating an unknown temporal off-set, i.e., the residence time, between the death of a shell and its subsequent entombment. To quantify the residence time during the Holocene on a section of the northern Chinese coastline a total 47 shelly subsamples were taken from 17 discrete layers identified on the west coast of Bohai Bay. This material was AMS 14C dated and the calibrated ages were systematically compared. The subsamples were categorized by type as articulated and disarticulated bivalves, gastropod shells, and undifferentiated shell-hash. It was found that within most individual layers the calibrated ages of the subsamples got younger relative to the amount of apparent post-mortem re-working the material had been subject to. For examples, the 14C ages of the bivalve samples trended younger in this order: shell-hash → split shells → articulated shells. We propose that the younger subsample age determined within an individual layer will be the closest to the actual depositional age of the material dated. Using this approach at four Holocene sites we find residence times which range from 100 to 1260 cal yrs, with two average values of 600 cal yrs for the original 14C dates older than 1 ka cal BP and 100 cal yrs for the original 14C dates younger than 1 ka cal BP, respectively. Using this semi-empirical estimation of the shell residence times we have refined the existing chronology of the Holocene chenier ridges on the west coast of Bohai Bay.

  5. 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...

  6. 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.

  7. [Study on the changes of macrobenthos communities and their causes in Bohai Bay].

    Science.gov (United States)

    Cai, Wen-Qian; Liu, Lu-San; Qiao, Fei; Lin, Kui-Xuan; Zhou, Juan

    2012-09-01

    Based on the analysis of macrobenthos samples collected from Bohai Bay, China in 2011 and the data obtained from the nearly the same sampling area during last six years, as well as the hydrological conditions, nutrients and dissolved oxygen, the characteristics of the changes in macrobenthos communities and their response to environmental variables were derived. Results showed that the distribution of the values of species number, abundance, biomass, richness index and diversity index reflected a gradient from the coastline to the open sea with the higher values concentrated at the open sea in the north part of Haihe estuary. The macrobenthos communities showed an obvious fluctuation over last six years, composed of three nodes. The first time node was in 2005 and 2008, the total species number, abundance and biomass maintained relatively high; the second time node was in 2009 and 2010, the values of the above three indices were the lowest in the three time nodes due to the increasing anthropogenic disturbances and natural changes; the third time node was in 2011, the values of the above three indices were the highest since many effective environmental protection measures had been carried out, indicating that the macrobenthos communities were recovered to a certain degree. The integrated impacts from the physical, chemical and biological variables induced by natural changes and anthropogenic disturbances, such as over-fishing, coastal land reclamation and sewage discharge were the triggers for the changes of macrobenthos communities. Furthermore, the variation characteristics of macrobenthic communities and environmental factors were generally in accordance with each other. PMID:23243866

  8. 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.

  9. 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

  10. 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. PMID:26952993

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

    OpenAIRE

    Jihong Chen; Zheng Wan; Fangwei Zhang; Nam-kyu Park; Xinhua He; Weiyong Yin

    2016-01-01

    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 ...

  12. 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.

  13. 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.

  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. 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.

  16. 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

  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. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. 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...

  5. 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。

  6. Ecological risk assessment and sources of heavy metals in sediment from Daling River basin.

    Science.gov (United States)

    Zhao, Lei; Mi, Dong; Chen, Yifu; Wang, Luo; Sun, Yeqing

    2015-04-01

    To investigate the distribution, source, and ecological risk of heavy metals in Daling River basin, 28 surface sediments collected in this region were analyzed by experimental and theoretical methods. Seven heavy metals, including Pb, Cr, Hg, Cu, As, Cd, and Zn, were detected in all samples. Monte Carlo simulation was used to assess the ecological risks of these heavy metals. It was found that the pollution of Cd was the most serious; the ecological risks in Daling River and Bohai Bay were significantly higher than those in estuary, Bohai Sea, and wetland, but overall, the ecological risks of these heavy metals were low to aquatic organisms in Daling River basin at present. Correlation analysis, principal component analysis, and cluster analysis showed that these heavy metals might originate from the same pollution sources located near Daling River and Bohai Bay. PMID:25378031

  7. 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

  8. 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.

  9. 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.

  10. 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.

  11. 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。

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. Factors influencing best management practice implementation in Virginia's Chesapeake Bay drainage basin

    OpenAIRE

    Lowery, James B.

    1996-01-01

    A survey of farmers was conducted to determine the extent of cost-share and non-costshare BMP implementation and to evaluate the impact of socio-economic variables of the adoption of BMPs in Virginia's Chesapeake Bay drainage basin. Farmers in 67 counties in Virginia were randomly selected using VirGIS land use data and GRASS 4.1. All of the counties included in the study had at least 90 percent of their total land in the Chesapeake Bay drainage basin. Surveys were mailed to ap...

  20. 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.

  1. 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.

  2. 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.

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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.

  8. 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.

  9. 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

  10. 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

  11. 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...

  12. 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.

  13. 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

  14. Basin filling related to the Philippine Sea Plate motion in Beppu Bay, southwest Japan

    Science.gov (United States)

    Yamada, Keitaro; Takemura, Keiji; Kuwae, Michinobu; Ikehara, Ken; Yamamoto, Masanobu

    2016-03-01

    Strike-slip basins are one of the most important accumulation spaces for sediment of terrigenous, biogenic, and volcanic origins, and generally include large amount of event deposits. Although these event deposits are important basin filling process, research on this topic, particularly the effects of event deposits, is insufficient. In this study, we discuss sedimentation features based on grain composition and other properties for ca. 3000 year periods in Beppu Bay, which is strike-slip basin located at the western end of an arc-bisecting dextral fault known as Median Tectonic Line (MTL) associated with the northwestward subduction of the Philippine Sea Plate. This sediment is composed of hemipelagic clay and coarser event layers of turbidites referred to as types A, B, and C; ash layers referred to as type D; and other referred to as type E. The turbidite event layers, which accounted for 92% of the total major event layer, with >1 cm thickness, consist of particles related to volcanism, including hydrothermal activity. The events control the regional filling rate and transportation of coarse and heavy volcaniclastic materials. In particular, type A, which accounted for 73% of the total major event layer thickness, is likely induced by earthquakes related to the MTL, according to its age. As a result, the basin filling processes are controlled mainly by tectonics related to the subduction of the Philippine Sea Plate.

  15. Authorization Basis Safety Classification of Transfer Bay Bridge Crane at the 105-K Basins

    International Nuclear Information System (INIS)

    This supporting document provides the bases for the safety classification for the K Basin transfer bay bridge crane and the bases for the Structures, Systems, and Components (SSC) safety classification. A table is presented that delineates the safety significant components. This safety classification is based on a review of the Authorization Basis (AB). This Authorization Basis review was performed regarding AB and design baseline issues. The primary issues are: (1) What is the AB for the safety classification of the transfer bay bridge crane? (2) What does the SSC safety classification ''Safety Significant'' or ''Safety Significant for Design Only'' mean for design requirements and quality requirements for procurement, installation and maintenance (including replacement of parts) activities for the crane during its expected life time? The AB information on the crane was identified based on review of Department of Energy--Richland Office (RL) and Spent Nuclear Fuel (SNF) Project correspondence, K Basin Safety Analysis Report (SAR) and RL Safety Evaluation Reports (SERs) of SNF Project SAR submittals. The relevant correspondence, actions and activities taken and substantive directions or conclusions of these documents are provided in Appendix A

  16. Authorization Basis Safety Classification of Transfer Bay Bridge Crane at the 105-K Basins

    Energy Technology Data Exchange (ETDEWEB)

    CHAFFEE, G.A.

    2000-04-06

    This supporting document provides the bases for the safety classification for the K Basin transfer bay bridge crane and the bases for the Structures, Systems, and Components (SSC) safety classification. A table is presented that delineates the safety significant components. This safety classification is based on a review of the Authorization Basis (AB). This Authorization Basis review was performed regarding AB and design baseline issues. The primary issues are: (1) What is the AB for the safety classification of the transfer bay bridge crane? (2) What does the SSC safety classification ''Safety Significant'' or ''Safety Significant for Design Only'' mean for design requirements and quality requirements for procurement, installation and maintenance (including replacement of parts) activities for the crane during its expected life time? The AB information on the crane was identified based on review of Department of Energy--Richland Office (RL) and Spent Nuclear Fuel (SNF) Project correspondence, K Basin Safety Analysis Report (SAR) and RL Safety Evaluation Reports (SERs) of SNF Project SAR submittals. The relevant correspondence, actions and activities taken and substantive directions or conclusions of these documents are provided in Appendix A.

  17. 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.

  18. 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

  19. 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

  20. 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

  1. Extensive occurrence and genesis of authigenic carbonates from Krishna-Godavari offshore basin (Bay of Bengal): Possible influence of methane hydrates occurrences.

    Digital Repository Service at National Institute of Oceanography (India)

    Kocherla, M.; Pillai, S.; Patil, D.J.

    investigation for comprehensive understanding of the process involved. The cores were collected as part of our gas hydrate exploration program from KG Basin, Bay of Bengal. One of the objectives of the Gas-hydrate research program at National Institute...

  2. 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.

  3. 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

  4. 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

  5. Gazetteer of hydrologic characteristics of streams in Massachusetts; coastal river basins of the South Shore and Buzzards Bay

    Science.gov (United States)

    Wandle, S.W.; Morgan, M.A.

    1984-01-01

    The coastal river basins include the minor river basins draining into Massachusetts Bay along the South Shore or into Buzzards Bay. The larger of these basins are the North, South, Jones, Wareham, Weweantic, Mattapoisett, Acushnet, and Slocums River basins. Drainage areas, using the latest available 1:24,000 scale topographic maps, were computed for data collection sites. Statistics on streamflow characteristics computed with a new data base are presented for six gaged streams. Daily-flow records through 1982 were used to compute annual and monthly flow statistics, duration of daily flow values, and the annual 7-day mean low flow at the 2-year and 10-year recurrence intervals. Seven-day low-flow statistics are presented for 49 partial-record sites and procedures used to determine the hydrologic characteristics of the basin are summarized. This gazetteer will aid in the planning and siting of water-resources related activities and will provide a common data base for governmental agencies and the engineering and planning communities. (USGS)

  6. 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.

  7. Sea ice density estimation in the Bohai Sea using the hyperspectral remote sensing technology

    Science.gov (United States)

    Liu, Chengyu; Shao, Honglan; Xie, Feng; Wang, Jianyu

    2014-11-01

    Sea ice density is one of the significant physical properties of sea ice and the input parameters in the estimation of the engineering mechanical strength and aerodynamic drag coefficients; also it is an important indicator of the ice age. The sea ice in the Bohai Sea is a solid, liquid and gas-phase mixture composed of pure ice, brine pockets and bubbles, the density of which is mainly affected by the amount of brine pockets and bubbles. The more the contained brine pockets, the greater the sea ice density; the more the contained bubbles, the smaller the sea ice density. The reflectance spectrum in 350~2500 nm and density of sea ice of different thickness and ages were measured in the Liaodong Bay of the Bohai Sea during the glacial maximum in the winter of 2012-2013. According to the measured sea ice density and reflectance spectrum, the characteristic bands that can reflect the sea ice density variation were found, and the sea ice density spectrum index (SIDSI) of the sea ice in the Bohai Sea was constructed. The inversion model of sea ice density in the Bohai Sea which refers to the layer from surface to the depth of penetration by the light was proposed at last. The sea ice density in the Bohai Sea was estimated using the proposed model from Hyperion image which is a hyperspectral image. The results show that the error of the sea ice density inversion model is about 0.0004 g•cm-3. The sea ice density can be estimated through hyperspectral remote sensing images, which provide the data support to the related marine science research and application.

  8. 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.

  9. 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)

  10. 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

  11. 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.

  12. Investigation of 3-D basin structures in the İzmit Bay area (Turkey) by single-station microtremor and gravimetric methods

    Science.gov (United States)

    Özalaybey, Serdar; Zor, Ekrem; Ergintav, Semih; Tapırdamaz, M. Cengiz

    2011-08-01

    We investigate 3-D basin structures and site resonance frequencies in the İzmit Bay area of Turkey by new geophysical surveys based on 239 single station microtremor and 405-point gravity measurements. A fundamental resonance frequency map of the İzmit Bay was produced from the main peak in the horizontal-to-vertical component spectral ratio (HVSR) of microtremors. The HVSR analysis of the microtremor data reveals single, double, broad peaked or no peak type HVSR curves varying in accordance with the surface geology and spatial extent of the three basins present in the İzmit Bay area. In the deepest sections of the İzmit, Gölcük and Derince basins of the İzmit Bay, the fundamental resonance frequencies are dominantly 0.24-0.30 Hz. These resonance frequencies should be taken into consideration along with higher mode frequencies to construct earthquake resistant structures in the İzmit Bay area. The 3-D gravimetric bedrock depth map of the İzmit basin shows that the basin has an asymmetric shape with its deepest section coinciding with the surface trace of the North Anatolian Fault. The northern shoulder of the basin has a gentle dip on the Kocaeli Peneplain side and the southern shoulder is much steeper, and it is bounded by the Samanlı Mountains. We derive a power-law relationship that correlates the fundamental site resonance frequencies with the sedimentary cover thickness obtained from the gravity and shear wave velocity data in the İzmit Bay. We use this relationship to estimate bedrock depths beneath Gölcük and Derince basins. Our estimation of maximum basin depths is 1400 m for the İzmit and is 800 m for the Gölcük and Derince basins. Finally, we have analysed a converted Sp phase from a local earthquake recording made at site CMP to calculate and verify the sediment thickness estimations obtained from our gravimetric and microtremor analyses. This calculation shows close agreement with that of the gravimetric and microtremor results. Our

  13. Inventory of nutrients in the Bohai

    Science.gov (United States)

    Mei Liu, Su; Wei Li, Ling; Zhang, Zhinan

    2011-10-01

    Biogeochemical observations were carried out to address the influence of major sources on nutrient composition and the ecosystem of the Bohai. Relatively high concentrations of nutrients off the Huanghe mouth and the shallow water areas were observed in the Bohai suggesting the effects of tidal and residual currents and anthropogenic perturbation. Sediment in the Bohai represents a source for ammonium, phosphate and dissolved silicate, while it is a sink for nitrite and nitrate. Benthic nutrient fluxes were 2-3 times higher than the riverine input with the regeneration rate of phosphate being slower relative to DIN and dissolved silicate. The release of dissolved silicate and phosphate from sediments may mitigate the decrease of dissolved silicate and phosphate due to the reduction of freshwater discharge. Compared with submarine groundwater discharge, nutrient regeneration in sediment provides similar DIN flux, 2-5 times phosphate and dissolved silicate fluxes. DIN/P molar ratios in the three mentioned sources were 155-845, indicating that phosphorus limitation for phytoplankton growth could be intensified, which likely results in changes of ecosystems of the Bohai.

  14. Total dissolved and total particulate copper in Abu-Kir bay a coastal Mediterranean basin under stress

    Science.gov (United States)

    Saad, M. A. H.; Badr, N. B.

    2003-05-01

    Abu-Kir Bay, a shallow semicircular basin east of Alexandria, has an area of 360 km^2, an average depth of 12 m and a volume of 4.32 km^3. It receives Nile water. brackish lakewater and highly polluted industrial waters. Vertical water samples were collected seasonally from the bay for studying the distribution of total dissolved copper (TDCu), total suspended matter (TSM) and total particulate copper (TPCu). The depth differences of TDCu values were associated with variations in salinities between the water layers. The increase in TDCu content at low salinity in the mixed zone is due to local anthropogenic input from Lake Edku. The stepwise regression model shows that pH was the main factor controlling the TDCu variations, especially at Tabia Sector (TS). Copper was transported mainly to the bay in particulate form, following the considerable input of TSM. During friction of the in-and outflowing water layers with different salinities at the Maadia Sector (MS), a complicated adsorption/desorption behavior of TSM could be expressed as a result of changes in pH, ionic Srength and solution composition. The enrichment of TpCu near the outfalls decreased gradually seaward. A significant positive correlation existed between TPCu and TSM in the surfixe layer of TS.

  15. 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.

  16. 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

  17. Diversity and distribution of catechol 2, 3-dioxygenase genes in surface sediments of the Bohai Sea.

    Science.gov (United States)

    He, Peiqing; Li, Li; Liu, Jihua; Bai, Yazhi; Fang, Xisheng

    2016-05-01

    Catechol 2, 3-dioxygenase (C23O) is the key enzyme for aerobic aromatic degradation. Based on clone libraries and quantitative real-time polymerase chain reaction, we characterized diversity and distribution patterns of C23O genes in surface sediments of the Bohai Sea. The results showed that sediments of the Bohai Sea were dominated by genes related to C23O subfamily I.2.A. The samples from wastewater discharge area (DG) and aquaculture farm (KL) showed distinct composition of C23O genes when compared to the samples from Bohai Bay (BH), and total organic carbon was a crucial determinant accounted for the composition variation. C6BH12-38 and C2BH2-35 displayed the highest gene copies and highest ratios to the 16S rRNA genes in KL, and they might prefer biologically labile aromatic hydrocarbons via aquaculture inputs. Meanwhile, C7BH3-48 showed the highest gene copies and highest ratios to the 16S rRNA genes in DG, and this could be selective effect of organic loadings from wastewater discharge. An evident increase in C6BH12-38 and C7BH3-48 gene copies and reduction in diversity of C23O genes in DG and KL indicated composition perturbations of C23O genes and potential loss in functional redundancy. We suggest that ecological habitat and trophic specificity could shape the distribution of C23O genes in the Bohai Sea sediments. PMID:27190241

  18. 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.

  19. 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...

  20. Indentifying environmental features for land management decisions. [Uinta Basin, Davis County foothills, and Farmington Bay in Utah

    Science.gov (United States)

    1980-01-01

    The wetlands and water-related land use in the Uinta Basin were classified and mapped using photointerpretation of U-2 infrared photography and digital LANDSAT data. The digital maps were used to augment photointerpretations. A highly effective diagnostic tool emerged when the LANDSAT digital print was photoreduced to a film positive at the same scale as the U-2 film and overlain on the U-2 color film. As a result of this merging technique, cover types can be identified more accurately and probablistic statements can be made about the relative amounts of water being consumed in one pasture vs. another. The hazards to urban development on sensitive and unstable land in the foothills of Davis County were studied using NASA U-2 photography. Shoreline fluctuations were mapped in the Farmington Bay using LANDSAT digital data.

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

    OpenAIRE

    Bigelow, Paul; Benda, Lee; Pearce, Sarah

    2016-01-01

    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 r...

  2. 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

  3. 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%;

  4. 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

  5. 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.

  6. 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.

  7. 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

  8. 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.

    of India and Sri Lanka. Key Words: Satellite altimetry, Geoid and gravity anomaly data, Bay of Bengal, Enderby Basin, Kerguelen and 86ºE FZs, Ninetyeast and 85°E ridges, transform-rift continental margin 1. Introduction The evolution of the eastern... experienced three major phases of seafloor spreading: initially moved in NW-SE direction until mid-Cretaceous, secondly drifted in N-S direction until early Tertiary and finally continuing in NE-SW direction. In the past, the lithospheric plates (Indian...

  9. 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.

  10. 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)

  11. 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.

  12. 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

  13. Relations of surface-water quality to streamflow in the Atlantic Coastal, lower Delaware River, and Delaware Bay Basins, New Jersey, water years 1976--1993

    Energy Technology Data Exchange (ETDEWEB)

    Hunchak-Kariouk, K.; Buxton, D.E.; Hickman, R.E.

    1999-01-01

    This report presents the results of analyses of 18 water-quality constituents in samples collected at 28 surface-water-quality stations within the Atlantic Coastal, lower Delaware River, and Delaware Bay Basins (referred to as the study area) during water years 1976--93 (October 1, 1975, through September 30, 1993). Relations between each of the 18 constituents and streamflow at the 28 stations over the period of record were determined by testing for trends in the concentrations of constituents during low and high flows. Qualitative values of contributions from constant (point sources and ground water) and intermittent (nonpoint storm runoff) sources were estimated statistically by examining the relations between concentrations of constituents and streamflow, and load and streamflow.

  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. 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.

  16. 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

  17. Hyperextension in the SE tip of the Bay of Biscay: a new tectonic model for the Cretaceous Basque-Cantabrian Basin, North Spain

    Science.gov (United States)

    Quintana, Luis; Pulgar, Javier A.; Alonso, Juan Luis; Pedreira, David

    2013-04-01

    The interest in the study of passive continental margins incorporated currently in orogenic systems has greatly increased in recent years, due to the possibility of observing in a direct way the structures responsible for the rupture of the continents. Many of these studies have revealed the existence of major extensional detachments, cross-cutting the whole crust, as the ones imaged by seismic methods in modern continental margins. In this work we present a model for the extensional structure of the Basque-Cantabrian Basin. This basin was the most subsident (almost 20 km of sediments) of all basins developed during the opening of the Bay of Biscay in the Mesozoic. The basin is currently incorporated into the Cantabrian-Pyrenean belt as a consequence of the Cenozoic (Alpine) convergence between the Iberian and European plates. The relatively minor overprint of contractional structures in this particular area, however, has allowed the precise reconstruction of the extensional structure. Extension was severe but without oceanization, and therefore it represents a good example to study intermediate stages of lithospheric rupture. The structure of the upper part of the crust was established through geological mapping and varied subsoil information have been taken into account. The structure of the middle and lower crust is derived from 3D gravity and magnetic modelling, constrained by deep seismic reflection and refraction profiles. These data have been integrated into a crustal-scale transect across the most subsiding part of the basin, and this transect was restored to its pre-contractional stage to display the extensional architecture. The structure of the upper part of the crust in the Iberian paleomargin consists of a wedge of syn-rift materials thickening towards the NE against a normal fault dipping to the SW, known as the Bilbao fault. In the footwall of this structure, the sedimentary succession is much thinner and rests almost directly on a dense and

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Investigation on the distribution and fate of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in a sewage-impacted bay

    International Nuclear Information System (INIS)

    The distribution and fate of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) were investigated in the water and sediment of Bohai Bay, China, during 2011–2013. A total of 360 water samples and 60 sediment samples were collected from 20 locations. The median concentrations of PFOS and PFOA were 4.8 and 12.15 ng/L in the water, and 2.65 and 0.62 ng/g-dry in the sediment, respectively. Significant enrichment were observed for PFOS and PFOA in water of sea surface microlayer. The concentrations of these two compounds showed an apparent gradient from nearshore to offshore stations. The correlation analysis and the distribution tendencies indicated that freshwater inflowing to the bay was the main source of PFOS and PFOA. The salinity of seawater and the total organic carbon (TOC) content of sediment heavily affected the spatial distribution and the partitioning of PFOS and PFOA in the sediment-water system. - Highlights: • We investigated the distribution and partitioning of PFOS and PFOA in Bohai Bay. • The PFOS and PFOA concentration showed a gradient from nearshore to offshore sites. • The PFOS and PFOA enriched significantly in the sea surface microlayer of water. • Inflowing freshwater was the main source of PFOS and PFOA in Bohai Bay. • Salinity and TOC deeply affected the distribution and partitioning of PFOS and PFOA. - The spatial and temporal distribution and the partitioning of perfluorooctane sulfonate and perfluorooctanoate were determined in the seawater-sediment system of Bohai Bay

  6. The influence of surface wave on water exchange in the Bohai Sea

    Science.gov (United States)

    Guo, Weijun; Wu, Guoxiang; Liang, Bingchen; Xu, Tiaojian; Chen, Xiaobo; Yang, Zhiwen; Xie, Mingxiao; Jiang, Meirong

    2016-04-01

    A three-dimensional wave-current coupled modeling system has been applied to analyze the water motions for the Bohai Sea and its adjacent waters. Two different methods of estimating the water exchange through the Bohai Strait have been employed, consisting of particle tracking and passive dye. The objectives of this study are to account for the surface wave role in the water exchange processes between the Bohai Sea and the outer waters, to test the response of the flushing characteristics of the Bohai Sea to different aspects of wave actions, and to obtain a quantitative and qualitative estimate of the half-life time under different experiment conditions. By comparing the simulations of water exchange with or without wave-current interactions, we find that waves can improve the Bohai Sea vertically mean water exchange capability, with more obvious enhancements for the surface layer where concentrated actions function. A series of numerical experiments indicate that turbulent kinetic energy from wave dissipation is the major positive influence, while wave-dependent surface stress, radiation stress, and Stokes drift have a minor effect. These results suggest that wave-driven mixing should be considered in the Bohai Sea water exchange processes, preferably using a half-life model based on concentration advection-diffusion model.

  7. 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.

  8. 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

  9. 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.

  10. 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

  11. 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.

  12. Emerging Persistent Organic Pollutants in Chinese Bohai Sea and Its Coastal Regions

    Directory of Open Access Journals (Sweden)

    Xiaomin Li

    2014-01-01

    Full Text Available Emerging persistent organic pollutants (POPs have widely aroused public concern in recent years. Polybrominated diphenyl ethers (PBDEs and perfluorooctane sulfonyl fluoride/perfluorooctane sulfonic acid (POSF/PFOS had been newly listed in Stockholm Convention in 2009, and short chain chlorinated paraffins (SCCPs and hexabromocyclododecanes (HBCDs were listed as candidate POPs. Bohai Sea is located in the arms of numbers of industrial cities, the semienclosed location of which makes it an ideal sink of emerging pollutants. In the present paper, latest contamination status of emerging POPs in Bohai Sea was reviewed. According to the literature data, Bohai Sea areas are not heavily contaminated by emerging POPs (PBDE: 0.01–720 ng/g; perfluorinated compounds: 0.1–304 ng/g; SCCPs: 64.9–5510 ng/g; HBCDs: nd-634 ng/g. Therefore, humans are not likely to be under serious risk of emerging POPs exposure through consuming seafood from Bohai Sea. However, the ubiquitous occurrence of emerging POPs in Bohai Sea region might indicate that more work should be done to expand the knowledge about potential risk of emerging POPs pollution.

  13. 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.

  14. 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.``

  15. Influence of basin-scale and mesoscale physical processes on biological productivity in the Bay of Bengal during the summer monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Muraleedharan, K.R.; Jasmine, P.; Achuthankutty, C.T.; Revichandran, C.; DineshKumar, P.K.; Anand, P.; Rejomon, G.

    . Academic press, New York, p. 662. Gomes, H., Goes, J.I., Saino, T., 2000. Influence of physical processes and freshwater discharge on the seasonality of phytoplankton regime in the Bay of Bengal. Continental Shelf Research 20, 313?330. Gopalakrishna, V... of planktonic foraminifera: sediment trap results from the Bay of Bengal, Northern Indian Ocean. Journal of Foraminiferal Research 27, 5?19. Harris, R.P., Wiebe, P.H., Lenz, J., Skjoldal, H.R., Huntley, M., 2000. ICES Zooplankton Methodology Manual. Academic...

  16. 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.

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

    Science.gov (United States)

    Bai, Jie; Li, Kuiran; Zhang, Jing; Li, Zhengyan; Gao, Huiwang; Zhang, Haofei

    2005-12-01

    Distribution, variation and impact factors of biomass of bacterioplankton from April to May 1999 in 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, Pbacterioplankton 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.

  18. 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

  19. 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.

  20. 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.

  1. 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)

  2. 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.

  3. Diagenesis of magnetic minerals in a gas hydrate/cold seep environment off the Krishna-Godavari basin, Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Dewangan, P.; Basavaiah, N.; Badesab, F.K.; Usapkar, A.; Mazumdar, A.; Joshi, R.; Ramprasad, T.

    occurs in interstices between the pyrite crystals. Such occurrence of greigite in sediments has important implications in the interpretation of paleomagnetic records. We evaluated the likely mechanism for the greigite formation in KG offshore basin...

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  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. 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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. A case study for a digital seabed database: Bohai Sea engineering geology database

    Science.gov (United States)

    Tianyun, Su; Shikui, Zhai; Baohua, Liu; Ruicai, Liang; Yanpeng, Zheng; Yong, Wang

    2006-07-01

    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.

  17. 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.

  18. 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

  19. 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.

  20. 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.

  1. A Framework Study of Bohai Sea Ice Comprehensive Service and Expert Aid Decision-making System

    OpenAIRE

    Jin Xifang; Guo Donglin; Wang Shuo; Zhao Xiangyu; Song Yan; Liu Aichao; Jiang Wenfei; Wang Ruifu; Li Xiaomin

    2015-01-01

    In this paper, we propose an overall framework about Bohai sea ice comprehensive service and expert aid decision-making system, among which six subsystems consists of sea ice multi-source information acquisition subsystem, sea ice comprehensive information database, sea ice comprehensive information integration subsystem, sea ice expert aid decision-making subsystem, sea ice products release subsystem, and sea ice disaster loss evaluation subsystem. The proposing system has such features as f...

  2. 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...

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. 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

  9. 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

  10. Towards a sustainable future in Hudson Bay

    International Nuclear Information System (INIS)

    To date, ca $40-50 billion has been invested in or committed to hydroelectric development on the rivers feeding Hudson Bay. In addition, billions more have been invested in land uses such as forestry and mining within the Hudson Bay drainage basin. However, there has never been a study of the possible impacts on Hudson Bay resulting from this activity. Neither has there been any federal environmental assessment on any of the economic developments that affect Hudson Bay. To fill this gap in knowledge, the Hudson Bay Program was established. The program will not conduct scientific field research but will rather scan the published literature and consult with leading experts in an effort to identify biophysical factors that are likely to be significantly affected by the cumulative influence of hydroelectric and other developments within and outside the region. An annotated bibliography on Hudson Bay has been completed and used to prepare a science overview paper, which will be circulated for comment, revised, and used as the basis for a workshop on cumulative effects in Hudson Bay. Papers will then be commissioned for a second workshop to be held in fall 1993. A unique feature of the program is its integration of traditional ecological knowledge among the Inuit and Cree communities around Hudson Bay with the scientific approach to cumulative impact assessment. One goal of the program is to help these communities bring forward their knowledge in such a way that it can be integrated into the cumulative effects assessment

  11. 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.

  12. Seasonal transportation and deposition of the suspended sediments in the Bohai Sea and Yellow Sea and the related mechanisms

    Science.gov (United States)

    Qiao, Lulu; Zhong, Yi; Wang, Nan; Zhao, Ke; Huang, Lingling; Wang, Zhen

    2016-05-01

    The Yellow River is well known for high concentration of suspended particulate matter (SPM), which is one of the most important SPM sources in the Bohai Sea and Yellow Sea, China. The mechanisms of long-distance transport and deposition of the Yellow River sediment discharges are hot topics. Based on field observations in four different seasons of 2010-2011 and 15 numerical experiments, this work studied the seasonal sediment transportation and deposition in the Bohai and Yellow Seas. Results show that the horizontal distribution of suspended sediment concentration in the Bohai Sea and Yellow Sea is neither closely related to the Yellow River discharge in flood and dry seasons nor to the temperature and salinity distributions in winter and summer because most of the Yellow River-discharged sediments deposited near the river mouth. However, the winter northerly wind events, especially the winter storm events with high waves, are the major factors inducing the long-distance transport of the sediments from the Bohai Sea to the Yellow Sea. The net SPMs are transported to the Yellow Sea from the Bohai Sea in both winter and summer. The net SPM flux at the Bohai Strait is 14.0 Mt/year by the combined effects of tides, wind, and waves. The SPM is transported to the Shandong Peninsula in the Yellow Sea for the generation of the mud wedge off the peninsula. The northern part of the mud wedge is related to the southerly wind in summer, and the southeastern part resulted from the winter northerly wind, especially the strong wind.

  13. 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

  14. Spatial distribution of dimethylsulfide and dimethylsulfoniopropionate in the Yellow Sea and Bohai Sea during summer

    Science.gov (United States)

    Yang, Jian; Yang, Guipeng; Zhang, Honghai; Zhang, Shenghui

    2015-07-01

    The distributions of dimethylsulfide (DMS) and its precursor dimethylsulfoniopropionate (DMSP) in surface water of the Yellow Sea and the Bohai Sea were studied during June 2011. The mean concentrations and ranges of DMS, dissolved DMSP (DMSPd), and particulate DMSP (DMSPp) in surface waters were 6.85 (1.60-12.36), 7.25 (2.28-19.05) and 61.87 (6.28-224.01) nmol/L, respectively. There were strong correlations between DMSPp and chlorophyll a in the Bohai Sea and the North Yellow Sea, respectively, and concentrations of DMS and DMSP were high, with a relatively high proportion of dinoflagellates, in the region of the South Yellow Sea Cold Water Mass. Results show that phytoplankton biomass and species composition were important factors that controlled the distribution of DMS and DMSP. Complex environmental factors, including nutrients, transparency, and terrestrial runoff, might also influence the variability in DMS and DMSP. Biological production and consumption rates of DMS in the Bohai Sea were higher than those in the Yellow Sea. DMS production rates were closely correlated with DMSPd concentrations. DMS and DMSP exhibited obvious diel variations, with high concentrations occurring in the late afternoon (16:00-19:00) and low concentrations occurring during the night, implying that the intensity of solar radiation had a significant influence on these variations. Size distributions of chlorophyll a and DMSPp were also investigated and large nanoplankton (5-20 μm), mainly diatoms, contributed significantly to chlorophyll a and DMSPp at most stations. The average sea-to-air flux of DMS in the study area was estimated to be 11.07 μmol/(m2·d) during the summer.

  15. 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.

  16. 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...

  17. 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.

  18. 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.

  19. 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.

  20. 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

  1. 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.

  2. Food utilization of adult flatfishes co-occurring in the Bohai Sea of China

    Science.gov (United States)

    Shuozeng, Dou

    Stomach contents were examined of 4527 adult individuals of 12 flatfish species collected during the 1982-1983 Bohai Sea Fisheries Resources Investigation. Their food habits, diet diversity, similarity of prey taxa, trophic niche breadth and diet overlap were systematically analysed. Ninety-seven prey species belonging to the Coelenterata, Nemertinea, Polychaeta, Mollusca, Crustacea, Echinodermata, Hemichordata and fish were found and five of them were considered to be principal prey for flatfishes: Alpheus japonicus, Oratosquilla oratoria, Alpheus distinguendus, Loligo japonicus and Crangon affinis. Among the flatfishes, Paralichthys olivaceus was piscivorous, whereas Pseudopleuronectes yokohamae and Pseudopleuronectes herzensteini both had polychaetes and molluscs as their main prey groups. Pleuronichthys cornutus was classified as a polychaete-mollusc eater, with a strong preference for crustaceans. Verasper variegatus, Cynoglossus semilaevis, Eopsetta grigorjewi and Cleisthenes herzensteini ate crustaceans. Kareius bicoloratus was classified as a mollusc-crustacean eater. Cynoglossus abbreviatus, Cynoglossus joyneri and Zebrias zebra were grouped as crustacean-fish eaters. However, Z. zebra also took polychaetes and C. abbreviatus and C. joyneri preyed on some molluscs. Trophic relationships among the flatfishes were complicated, but they occupied distinctive microhabitats in different seasons and selected their specific prey items, which was favourable to the stability of the flatfish community in the Bohai Sea.

  3. 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.

  4. Modeling of oil spill beaching along the coast of the Bohai Sea, China

    Science.gov (United States)

    Xu, Qing; Cheng, Yongcun; Liu, Bingqing; Wei, Yongliang

    2015-12-01

    On June 4 and 17, 2011, two separate oil spill accidents occurred at platforms B and C of the Penglai 19-3 oilfield located in the Bohai Sea, China. Based on the initial oil spill locations detected from the first available Synthetic Aperture Radar (SAR) image acquired on June 11, 2011, we performed a numerical experiment to simulate the potential oil spill beaching area with the General NOAA Operational Modeling Environment (GNOME) model. The model was driven by ocean surface currents from an operational ocean model (Navy Coastal Ocean Model) and surface winds from operational scatterometer measurements (the Advanced Scatterometer). Under the forcing of wind and ocean currents, some of the oil spills reached land along the coast of Qinhuangdao within 12 days. The results also demonstrate that the ocean currents are likely to carry the remaining oil spills along the Bohai coast towards the northeast. The predicted oil spill beaching area was verified by reported in-situ measurements and former studies based on MODIS observations.

  5. 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.

  6. 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.

  7. 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.

  8. Oil-water separation property of polymer-contained wastewater from polymer-flooding oilfields in Bohai Bay, China.

    Science.gov (United States)

    Chen, Hua-xing; Tang, Hong-ming; Duan, Ming; Liu, Yi-gang; Liu, Min; Zhao, Feng

    2015-01-01

    In this study, the effects of gravitational settling time, temperature, speed and time of centrifugation, flocculant type and dosage, bubble size and gas amount were investigated. The results show that the simple increase in settling time and temperature is of no use for oil-water separation of the three wastewater samples. As far as oil-water separation efficiency is concerned, increasing centrifugal speed and centrifugal time is highly effective for L sample, and has a certain effect on J sample, but is not valid for S sample. The flocculants are highly effective for S and L samples, and the oil-water separation efficiency increases with an increase in the concentration of inorganic cationic flocculants. There exist critical reagent concentrations for the organic cationic and the nonionic flocculants, wherein a higher or lower concentration of flocculant would cause a decrease in the treatment efficiency. Flotation is an effective approach for oil-water separation of polymer-contained wastewater from the three oilfields. The oil-water separation efficiency can be enhanced by increasing floatation agent concentration, flotation time and gas amount, and by decreasing bubble size. PMID:25420517

  9. 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.

  10. 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

  11. 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 ...

  12. 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.

  13. 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.

  14. Enhanced methane emissions from oil and gas exploration areas to the atmosphere--the central Bohai Sea.

    Science.gov (United States)

    Zhang, Yong; Zhao, Hua-de; Zhai, Wei-dong; Zang, Kun-peng; Wang, Ju-ying

    2014-04-15

    The distributions of dissolved methane in the central Bohai Sea were investigated in November 2011, May 2012, July 2012, and August 2012. Methane concentration in surface seawater, determined using an underway measurement system combined with wavelength-scanned cavity ring-down spectroscopy, showed marked spatiotemporal variations with saturation ratio from 107% to 1193%. The central Bohai Sea was thus a source of atmospheric methane during the survey periods. Several episodic oil and gas spill events increased surface methane concentration by up to 4.7 times and raised the local methane outgassing rate by up to 14.6 times. This study demonstrated a method to detect seafloor CH4 leakages at the sea surface, which may have applicability in many shallow sea areas with oil and gas exploration activities around the world. PMID:24602676

  15. Evidence of paleo-cold seep activity from the Bay of Bengal, offshore India

    Digital Repository Service at National Institute of Oceanography (India)

    Mazumdar, A.; Dewangan, P.; Joao, H.M.; Peketi, A.; Khosla, V.R.; Kocherla, M.; Badesab, F.K.; Joshi, R.K.; Roxanne, P.; Ramamurty, P.B.; Karisiddaiah, S.M.; Patil, D.J.; Dayal, A.M.; Ramprasad, T.; Hawkesworth, C.J.; Avanzinelli, R.

    Evidence of paleo–cold seep associated activities, preserved in methane-derived carbonates in association with chemosynthetic clams (Calyptogena sp.) from a sediment core in the Krishna-Godavari basin, Bay of Bengal is reported. Visual observations...

  16. 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...

  17. 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 ...

  18. 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.

  19. 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...

  20. 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

  1. 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...

  2. 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.

  3. 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....

  4. 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.

  5. Surface layer temperature inversion in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Pankajakshan, T.; Gopalakrishna, V.V.; Muraleedharan, P.M.; Reddy, G.V.; Araligidad, N.

    shows heat gain in this region, the organised inversions in this region appears to be generated by the cold fresher water advection (from the head of the bay and Irrawadi basin) over the remnant of the warm saline water in this region advected...

  6. 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

  7. 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

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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.

  13. Temporal and spatial variations of dimethylsulfoxide in the Bohai Sea and the Yellow Sea

    Science.gov (United States)

    Yang, Gui-Peng; Wang, Xin; Zhang, Hong-Hai; Liu, Chun-Ying

    2014-07-01

    Temporal and spatial distributions of dissolved and particulate dimethylsulfoxide (DMSOd and DMSOp) were determined in the Bohai Sea (BS) and the Yellow Sea (YS) during November-December 2011 and May 2012. The average concentrations of DMSOd and DMSOp in the surface water in autumn were 14.6 (6.48 - 52.3) and 10.0 (4.94-31.1) nmol L- 1, respectively, and those in spring were 19.7 (4.84-144) and 25.1 (5.09-108) nmol L- 1. The distributions of DMSOd and DMSOp in the study area were obviously influenced by biological production of phytoplankton. A positive correlation was observed between DMSOp and chlorophyll a (Chl-a) concentrations in the surface water in autumn, suggesting that phytoplankton biomass might play an important role in controlling the distribution of DMSOp in the study area. The spring average ratio of DMSOp/Chl-a was approximately 1.3 times higher than the autumn value, corresponding with the temporal variation in phytoplankton species and biomass between spring and autumn.

  14. 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...

  15. A reevaluation of the late quaternary sedimentation in todos os Santos Bay (BA, Brazil

    Directory of Open Access Journals (Sweden)

    GUILHERME C. LESSA

    2000-12-01

    Full Text Available Todos os Santos Bay is a large ( 1000 km², structurally controlled tidal bay in northeast Brazil. Three main drainage basins debouch into the bay, providing a mean freshwater discharge of 200 m³/s (prior to 1985, or less than 1% of the spring tidal discharge through the bay mouth. Based on the result of several sedimentological studies performed in the 1970's, five surface sedimentary facies were identified inside the bay, namely i transgressive siliciclastic marine sand facies; ii transgressive bay sand-mud facies; iii a transgressive carbonate marine sand facies; iv regressive bay-mud facies, and v regressive fluvial sand facies. The spatial distribution of these facies would follow, somewhat closely, the hydrodynamic-energy distribution inside the bay. Seismic profiles along the bay bottom indicate the existence of several paleochannels, 5-10 m deep, blanketed at least by three different sedimentary units. The topmost sedimentary unit, 5-20 m thick, appears to be associated with the regressive bay-mud facies, and assuming that it was laid down within the last 5000 years, sedimentation rates for the central and northeastern part of the bay would average at 2,4 mm/y.

  16. 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.

  17. 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...

  18. 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.

  19. 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.

  20. 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.

  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. Speciated atmospheric mercury in the marine boundary layer of the Bohai Sea and Yellow Sea

    Science.gov (United States)

    Wang, Chunjie; Ci, Zhijia; Wang, Zhangwei; Zhang, Xiaoshan; Guo, Jia

    2016-04-01

    The objectives of this study are to identify the spatial and temporal distributions of gaseous elemental mercury (GEM), reactive gaseous mercury (RGM), and fine particulate mercury (HgP2.5) in the marine boundary layer (MBL) of the Bohai Sea (BS) and Yellow Sea (YS), and to investigate the relationships between mercury species and meteorological parameters. The mean concentrations of GEM, RGM, and HgP2.5 were 2.03 ng m-3, 2.5 pg m-3, and 8.2 pg m-3 in spring, and 2.09 ng m-3, 4.3 pg m-3, and 8.3 pg m-3 in fall. Reactive mercury (RGM + HgP2.5) represented export in the MBL was GEM and the direct outflow of reactive mercury was very small. Moreover, GEM concentrations over the BS were generally higher than those over the YS both in spring and fall. Although RGM showed a homogeneous distribution over the BS and YS both in spring and fall, the mean RGM concentration in fall was significantly higher than that in spring. In contrast, the spatial distribution of HgP2.5 generally reflected a gradient with high levels near the coast of China and low levels in the open sea, suggesting the significant atmospheric mercury outflow from China. Interestingly, the mean RGM concentrations during daytime were significantly higher than those during nighttime both in spring and fall, while the opposite results were observed for HgP2.5. Additionally, RGM positively correlates with air temperature while negatively correlates with relative humidity. In conclusion, the elevated atmospheric mercury levels in the BS and YS compared to other open seas suggested that the human activities had a significant influence on the oceanic mercury cycle downwind of China.

  3. 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.

  4. 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

  5. Investigation of organochlorine pesticides (OCPs) in mollusks collected from coastal sites along the Chinese Bohai Sea from 2002 to 2004

    International Nuclear Information System (INIS)

    Mollusks living in seas can accumulate organochlorine pesticides (OCPs). The residue levels of selected OCPs: dichlorodiphenyltrichloroethane (p,p'-DDT, o,p'-DDT, p,p'-DDE, p,p'-DDD), hexachlorocyclohexanes (α-, β-, γ- and δ-HCH) in gastropod and bivalve species collected from ten coastal cites along the Chinese Bohai Sea were investigated from 2002 to 2004. The species included nine kinds of mollusks: Rapana venosa, Neverita didyma, Scapharca subcrenata, Mytilus edulis, Amusium, Crassostrea talienwhanensis, Meretix meretrix, Sinonovacula constricta, Ruditapes philippinarum, Mactra veneriformis. The results showed that OCPs widely existed in the mollusks organisms. p,p'-DDT, p,p'-DDE, β-HCH were the major compounds. Statistical analysis (One-way ANOVA) showed that the contents of OCPs in these mollusks did not change obviously from 2002 to 2004. Principal component analysis (PCA) was also used for determining the polluting characters existing in this selected field. - Concentration of organochlorine pesticides in mollusks collected from coastal sites along the Chinese Bohai Sea didn't change obviously from 2002 to 2004

  6. 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.

  7. 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.

  8. Investigation of organochlorine pesticides (OCPs) in mollusks collected from coastal sites along the Chinese Bohai Sea from 2002 to 2004

    Energy Technology Data Exchange (ETDEWEB)

    Wang Yawei [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, 18 Shuangqing Road, Haidian District, Beijing 100085 (China); Yang Ruiqiang [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, 18 Shuangqing Road, Haidian District, Beijing 100085 (China); Jiang Guibin [State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, P.O. Box 2871, 18 Shuangqing Road, Haidian District, Beijing 100085 (China)]. E-mail: gbjiang@rcees.ac.cn

    2007-03-15

    Mollusks living in seas can accumulate organochlorine pesticides (OCPs). The residue levels of selected OCPs: dichlorodiphenyltrichloroethane (p,p'-DDT, o,p'-DDT, p,p'-DDE, p,p'-DDD), hexachlorocyclohexanes ({alpha}-, {beta}-, {gamma}- and {delta}-HCH) in gastropod and bivalve species collected from ten coastal cites along the Chinese Bohai Sea were investigated from 2002 to 2004. The species included nine kinds of mollusks: Rapana venosa, Neverita didyma, Scapharca subcrenata, Mytilus edulis, Amusium, Crassostrea talienwhanensis, Meretix meretrix, Sinonovacula constricta, Ruditapes philippinarum, Mactra veneriformis. The results showed that OCPs widely existed in the mollusks organisms. p,p'-DDT, p,p'-DDE, {beta}-HCH were the major compounds. Statistical analysis (One-way ANOVA) showed that the contents of OCPs in these mollusks did not change obviously from 2002 to 2004. Principal component analysis (PCA) was also used for determining the polluting characters existing in this selected field. - Concentration of organochlorine pesticides in mollusks collected from coastal sites along the Chinese Bohai Sea didn't change obviously from 2002 to 2004.

  9. 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.

  10. 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...

  11. 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...

  12. 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.

  13. 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...

  14. 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...

  15. 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

  16. 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.

  17. 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....

  18. 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....

  19. 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....

  20. 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.

  1. 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.

  2. Tidal power dams in the Bay of Fundy

    International Nuclear Information System (INIS)

    The challenges of harnessing tidal power and the construction of dams and tidal power plants in a tidal-ocean environment such as the Bay of Fundy in New Brunswick are discussed. In the 1966-1988 series of studies, three sites were chosen at the Bay of Fundy as being the most promising, namely (1) site B9 in Minas Basin at the entrance to Cobequid Bay, (2) site A8 at the narrow neck beyond the entrance to Cumberland Basin, and (3) site A6 at the entrance to Shepody Bay. All the sites are located at the head of the Bay of Fundy because that is where the maximum tidal ranges are found and a basin's tidal energy potential is proportional to the square of its tidal range. Site B9 was determined to have the greatest tidal power potential but no plant has ever been built because reports have stated that a solid conventional tidal power barrage at site B9 would increase the tidal range at Boston by as much as 30 cm. Rather than abandoning the site for this reason, an installation consisting of a series of piers from shore to shore with hydraulic turbines mounted in the spaces between piers, was suggested. A simple mathematical model has been developed for determining the operation of this tidal fence. The cost of energy, generated by the tidal fence at site B9 was also calculated. Further studies are suggested to determine the exact environmental effect of the tidal fence on the tidal regime. If environmental problems persist, machines with larger discharge capabilities could be considered to reduce the interference of the fence with natural tidal movements. 9 refs., 6 figs

  3. Humic Substances from Manila Bay and Bolinao Bay Sediments

    OpenAIRE

    Elma Llaguno

    1997-01-01

    The C,H,N composition of sedimentary humic acids (HA) extracted from three sites in Manila Bay and six sites in Bolinao Bay yielded H/C atomic ratios of 1.1-1.4 and N/C atomic ratios of 0.09 - 0.16. The Manila Bay HA's had lower H/C and N/C ratios compared to those from Bolinao Bay. The IR spectra showed prominent aliphatic C-H and amide I and II bands. Manila Bay HA's also had less diverse molecular composition based on the GC-MS analysis of the CuO and alkaline permanganate oxidation produc...

  4. Humic substances from Manila Bay and Bolinao Bay sediments

    International Nuclear Information System (INIS)

    The C, H, N composition of sedimentary humic acids (HA) extracted from three sites in Manila Bay and six sites in Bolinao Bay yielded H/C atomic ratios of 1.1-1.4 and N/C atomic ratios of 0.09-0.16. The Manila Bay HA's had lower H/C and C/C ratios compared to those from Bolinao Bay. The IR spectra showed prominent aliphatic C-H amide I and II bands. Manila Bay HA's also had less diverse molecular composition based on the GC-MS analysis of the CuO and alkaline permanganate oxidation products of the humic acids. (Author)

  5. Monterey Bay geoid

    OpenAIRE

    Boener, Joseph H.

    1994-01-01

    A high resolution local geoid was calculated for the Monterey Bay, CA using local gravimetry data, digital elevation data and The Ohio State University OSU91A global geopotential model. The theoretical accuracy of the calculated local geoid is 3.5 cm or better over 5 km. Local gravity data came from three sources: 1,549 land observations from the Defense Mapping Agency, 179 bottom gravity observations from two Naval Postgraduate School gravity surveys of Monterey Bay and 17,098 National Geode...

  6. 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.

  7. Spatial-temporal characteristics and determinants of PM2.5 in the Bohai Rim Urban Agglomeration.

    Science.gov (United States)

    Wang, Zhen-bo; Fang, Chuang-lin

    2016-04-01

    Ambient particulate matter (PM) pollution of China has become a global concern and has great impact on air quality and human health. This paper adopts the PM2.5 concentration data obtained from 241 newly located observation points in the Bohai Rim Urban Agglomeration (BRUA), as well as economic, urban and industrial working population data in the study area, revealing the spatio-temporal distribution of PM2.5 and its determinants with the help of a spatial data model. The results indicate that: 1) The BRUA was the core area of PM2.5 pollution in China in 2014, the average PM2.5 concentration of which reached 74 μg/m(3), which is 13 μg/m(3) higher than the country average (61 μg/m(3)); 2) The PM2.5 concentration distribution had a characteristic of high in winter and autumn but low in spring and summer, presenting a U-shaped monthly profile and a U-impulse type daily profile; 3) The urban PM2.5 concentrations showed obvious spatial variation and agglomeration. The highest hot-spot was observed in spring, while the lowest was in summer. High concentration cities were mainly located in southern Hebei and western Shandong, and low concentration cities were in the coastal area around the Bohai Sea and the mountainous areas in northern Hebei. High hot-spot areas demonstrated an M-shaped change, with two cycles of advance and retreat from west to east. 4) The Geographically weighted regression (GWR) model shows that the GDP per capita, urbanization rate and construction of the cities were closely related to PM2.5 concentrations in the BRUA. PMID:26802272

  8. Subsidence in Gorontalo Bay, Sulawesi (Indonesia) and metamorphic core complex exhumation on land

    Science.gov (United States)

    Pezzati, Giovanni; Hennig, Juliane; Advokaat, Eldert; Hall, Robert; Burgess, Peter; Perez-Gussinye, Marta

    2015-04-01

    Gorontalo Bay is a semi-enclosed sea between the North and East Arms of Sulawesi. It is surrounded by land on three sides, separating a northern volcanic province from metamorphic rocks to the south and west, and ophiolites to the southeast. In the western part of Gorontalo Bay there are two sub-basins: the northern Tomini Basin and the southern Poso Basin, which have different histories. This study presents a new geological interpretation of western Gorontalo Bay, based on recent multibeam and 2D seismic data and field observations on land. In Tomini Basin six major seismic sequences (Units A to F) have a total thickness of more than 5 sec TWT. Ages are based on correlation with events on land. A major unconformity above Basement Unit A is interpreted to be the result of an Early Miocene collision. Unit A subsided from the Early Miocene, with deposition of Units B and C largely in a deep marine environment. There was regional uplift in the Middle Miocene followed by renewed subsidence resulting in shallow marine depositional environments in which carbonate platforms developed (Units D-E). Subsidence accelerated during the deposition of Unit E, causing back-stepping of the shelf edge, formation of pinnacle reefs and then drowning of the carbonate platforms, leading to the present depths of 2 km in the basin centre with a thin clastic cover (Unit F). North of Tomini Basin, the Malino Metamorphic Complex exposes strongly deformed mid-crustal rocks which record Middle Miocene extension accommodated by low angle shear zones. A second phase of rapid uplift and extension recorded in these rocks occurred in the Pliocene-Pleistocene, and was accommodated by high angle normal faulting. Poso Basin is younger than Tomini Basin and it occupies the southern part of western Gorontalo Bay. The deeper part of its sedimentary sequence is probably the time equivalent of Unit D in Tomini Basin. Immediately south of Poso Basin, on land, is a large metamorphic core complex. Seismic

  9. 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...

  10. 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.

  11. K West Basin canister survey

    International Nuclear Information System (INIS)

    A survey was conducted of the K West Basin to determine the distribution of canister types that contain the irradiated N Reactor fuel. An underwater camera was used to conduct the survey during June 1998, and the results were recorded on videotape. A full row-by-row survey of the entire basin was performed, with the distinction between aluminum and stainless steel Mark 1 canisters made by the presence or absence of steel rings on the canister trunions (aluminum canisters have the steel rings). The results of the survey are presented in tables and figures. Grid maps of the three bays show the canister lid ID number and the canister type in each location that contained fuel. The following abbreviations are used in the grid maps for canister type designation: IA = Mark 1 aluminum, IS = Mark 1 stainless steel, and 2 = Mark 2 stainless steel. An overall summary of the canister distribution survey is presented in Table 1. The total number of canisters found to contain fuel was 3842, with 20% being Mark 1 Al, 25% being Mark 1 SS, and 55% being Mark 2 SS. The aluminum canisters were predominantly located in the East and West bays of the basin

  12. 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。

  13. Basin evolution during change from convergent to transform continental margin in Central California

    Energy Technology Data Exchange (ETDEWEB)

    Graham, S.A.; Hitzman, M.; McCloy, C.; Turner, R.; Ward, R.

    1984-03-01

    Miocene nonmarine and shallow marine strata exposed east of San Francisco Bay record a change from convergent-margin tectonics to transform margin tectonics. During the middle Miocene, the East Bay area occupied the oceanward side of a shelved forearc basin that was progressively incorporated in the evolving San Andreas strike-slip orogene. Patterns of deposition in the broad forearc basin were relatively simple: andesitic arc-derived detritus was transported the full width of the forearc basin from the Sierras to the East Bay area. In contrast, the wrench-tectonic regime produced complex patterns of sedimentation displaying greater local variability. On the basis of stratigraphic data, we infer that the west-facing slope of the forearc basin in the East Bay area was reversed about 13 Ma with uplift of the area between the eventual traces of the San Andreas and Hayward faults on the site of the present bay. A fluvial clastic wedge was shed eastward into the East Bay area from this uplifted terrane of Mesozoic subduction complex and forearc basin rocks. Initial rupturing along the Hayward fault trend followed the uplift at about 10 Ma. Loci of basaltic volcanism (10-7 Ma) along these fractures interfinger with the clastic wedge. A similar pattern of uplift and drainage reversal apparently presaged the onset of wrenching along the nearby Calaveras trend from 8-6 Ma. Expansion of the strike-slip orogene segmented the outer forearc basin into local basins, some characterized by episodic lacustrine deposition and probable internal drainage. By the end of the Miocene, Sierran arc volcanism waned at the latitude of San Francisco Bay, and arc-derived volcaniclastics were fully supplanted by recycled Coast Range-derived detritus in the East Bay area. Certain of these Coast Range sediment sources, particularly blueschist-bearing Franciscan terranes, permit an estimate of 7-27 km (4-17 mi) of total right slip on the Hayward fault.

  14. 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.

  15. Upper Newport Bay Restoration Plan

    OpenAIRE

    Halsch, Chris; Wessling, Jaenna; Lister, Anne; Beck, Emily; Zembel, Richard; Yurko, Matt; Kimball, Sarah

    2016-01-01

    The overall goal of this restoration plan is to assist stakeholders in matching restoration projects with funding opportunities in order to increase the overall health of the Upper Newport Bay. Specifically, this document aims to assess current health and quality of native habitats in and around the bay, and to identify areas needing restoration. We have compiled data on the ecology of the bay, including extent of non-native plant invasion, restoration history and progress, site accessibility...

  16. 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...

  17. 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...

  18. Sediment transport off the Huanghe (Yellow River) delta and in the adjacent Bohai Sea in winter and seasonal comparison

    Science.gov (United States)

    Yang, Zuosheng; Ji, Youjun; Bi, Naishuang; Lei, Kun; Wang, Houjie

    2011-07-01

    Based on the data on the current velocity, water temperature, salinity, turbidity and concentration of suspended sediment collected in November 2006 along three survey transects at three time-series, ship-based stations off the Huanghe (Yellow River) delta, and at twenty-four grid survey stations in the adjacent Bohai Sea, sediment transport off the Huanghe delta and in the adjacent Bohai Sea under winter regime were studied and compared with those from the summer season. The homogeneous distribution of salinity, temperature and sediment in the water column indicated a well-mixed body of water. A zone of high suspended sediment concentrations (SSC) >100 mg l -1 with a width of 35 km was identified along the delta coast. Two highest SSC centers were found in the surface and middle water layers around the abandoned Diaokou Huanghe river mouth and the present Huanghe river mouth, and the third one in the bottom layer around the abandoned Qingshuigou Huanghe river mouth. These three highest SSC centers become major sediment source areas in winter. Based on the location of the high bottom shear stress zone, the prevailing wave directions and the protuberant topography of the river mouths, we identified the resuspension origin of the three highest SSC centers caused mostly by the winter storm waves, partially by tidal currents. Suspended sediment flux (SSF) along the three coastal transects indicated that the sediment in the northwest part of the delta was transported northeastward and southeastward along the coast of the recent delta lobe. The SSC and SSF were higher in winter than summer by 1.7-27.1 and 2-122.5 times, respectively, except around the present river mouth. This indicates that the intensity of sediment transport in winter is much stronger than in summer due to the powerful effect of winter storms although the river water and sediment discharges to the sea were much greater in summer. The massive Huanghe sediment to the sea was accumulated in a narrow

  19. 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

  20. 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.

  1. Humic Substances from Manila Bay and Bolinao Bay Sediments

    Directory of Open Access Journals (Sweden)

    Elma Llaguno

    1997-12-01

    Full Text Available The C,H,N composition of sedimentary humic acids (HA extracted from three sites in Manila Bay and six sites in Bolinao Bay yielded H/C atomic ratios of 1.1-1.4 and N/C atomic ratios of 0.09 - 0.16. The Manila Bay HA's had lower H/C and N/C ratios compared to those from Bolinao Bay. The IR spectra showed prominent aliphatic C-H and amide I and II bands. Manila Bay HA's also had less diverse molecular composition based on the GC-MS analysis of the CuO and alkaline permanganate oxidation products of the humic acids.

  2. 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

  3. 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.

  4. 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.

  5. 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

  6. 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.

  7. 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.

  8. Impact of agricultural waste burning in the Shandong Peninsula on carbonaceous aerosols in the Bohai Rim, China.

    Science.gov (United States)

    Wang, Xiaoping; Chen, Yingjun; Tian, Chongguo; Huang, Guopei; Fang, Yin; Zhang, Fan; Zong, Zheng; Li, Jun; Zhang, Gan

    2014-05-15

    A total of 11 5PM2.5 samples were collected for analyzing organic carbon (OC) and elemental carbon (EC) at Tuoji Island (TI), China from November 2011 to December 2012. The results showed that annual arithmetical means of OC and EC concentrations were 3.8 ± 2.7 and 2.2 ± 2.2 μg m(-3), which contributed 8% and 4% of PM2.5 mass concentrations, respectively. High EC concentrations occurred in winter, contributed mainly by EC outflow from the northwest source region, while high OC concentrations were found during spring, attributed largely to biofuel burning in the Shandong Peninsula, and short distance and favorable transport from the peninsula to the TI. Agricultural waste open burning in the peninsula caused the largest variability of OC concentration in summer. Eliminating agricultural field burning in the peninsula can reduce at least one-third of concentration levels and half of northward transport fluxes of OC and EC in Bohai Rim in summer. PMID:24607395

  9. 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.

  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. 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.

  12. Numerical Modelling of Oil Spills in the Area of Kvarner and Rijeka Bay (The Northern Adriatic Sea)

    OpenAIRE

    Goran Lončar; Gordana Beg Paklar; Ivica Janeković

    2012-01-01

    Several hypothetical cases of oil spills from tankers in the Kvarner and Rijeka Bay were analyzed using three-dimensional circulation models coupled with oil spill model. Two circulation models—local one covering the area of Kvarner Bay, Rijeka Bay, and Vinodol channel along with the basin-wide one covering the whole Adriatic Sea—are connected through the one-way nesting procedure by imposing the results from the Adriatic model to the open boundaries of the local one. Oil sp...

  13. 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...

  14. 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。

  15. 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.

  16. Island Bay Wilderness study area : Island Bay National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a brief report on a wilderness study area located in the Island Bay National Wildlife Refuge. It discusses the history of the study area, its...

  17. Vinna Basin

    Czech Academy of Sciences Publication Activity Database

    Honěk, J.; Franců, J.; Mikuláš, Radek; Pešek, J.; Sýkorová, Ivana; Tomanová-Petrová, P.

    Prague: Czech Geological Survey, 2014, s. 223-241 ISBN 978-80-7075-862-5 R&D Projects: GA ČR GA105/06/0653 Institutional support: RVO:67985891 ; RVO:67985831 Keywords : Tertiary basins * Czech Republic * Cenomanian and Tertiary lignite * geology * stratigraphy Subject RIV: DB - Geology ; Mineralogy

  18. 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.

  19. 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

  20. 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

  1. 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...

  2. 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...

  3. 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.

  4. 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.

  5. Sediment accumulation in San Leandro Bay, Alameda County, California, during the 20th century - A preliminary report

    International Nuclear Information System (INIS)

    Major changes made in the configuration of San Leandro Bay, Alameda County, California, during the 20th century have caused rapid sedimentation within parts of the Bay. Comparison of bathymetric surveys indicates that sedimentation in the vicinity of the San Leandro Bay channel averaged 0.7 cm/annum between 1856 and 1984. Lead-210 data collected at four shallow water sites east of the San Leandro Bay channel indicated that sedimentation rates have averaged between 0.06 and 0.28 cm/annum. Because bioturbation of bottom sediments cannot be discounted, better definition of this range in sedimentation rates would require measuring the activity of lead-210 on incoming sediments. In addition to sediment deposited in the vicinity of the San Leandro Bay channel and open, shallow areas to the east, 850,740 cu m of sediment was deposited between 1948 and 1983 in an area dredged at the mouth of San Leandro Creek. All available data indicate that between 1,213,000 and 1,364,000 cu m of sediment was deposited in San Leandro Bay between 1948 and 1983. Sediment yield data from an adjacent drainage basin, when combined with inventories of lead-210 and cesium-137, indicate that most of the sediment deposited in San Leandro Bay is coming from resuspension of bottom sediments or from erosion of marshes or shorelines of San Leandro or San Francisco Bay. 31 refs., 7 figs., 4 tabs

  6. Major and trace element geochemistry of Bay of Bengal sediments: Implications to provenances and their controlling factors

    Digital Repository Service at National Institute of Oceanography (India)

    Tripathy, G.R.; Singh, S.K.; Ramaswamy, V.

    ,2,*, Sunil Kumar Singh1 and V Ramaswamy2 1Geosciences Division, Physical Research Laboratory, Ahmedabad-380009, India 2National Institute of Oceanography, Dona Paula, Goa-403004, India *Corresponding Author: grtripathy@gmail.com Keywords: Bay... of these rivers to the global drainage area underscoring the important role of physical erosion in these river basins on the global sedimentary budget. Further, the erosion patterns of these river basins and their spatio-temporal variations have received...

  7. Occurrence and transport of 17 perfluoroalkyl acids in 12 coastal rivers in south Bohai coastal region of China with concentrated fluoropolymer facilities

    International Nuclear Information System (INIS)

    Perfluoroalkyl acids (PFAAs) are emerging contaminants that have raised great concern in recent years. While PFAAs manufacturing becomes regulated in developed countries, production has been partly shifted to China. Eight fluoropolymer manufacturing facilities located in the South Bohai coastal region, one of the most populated areas of China, have been used to manufacture PFAA-related substances since 2001. The environmental consequence of the intensive production of PFAAs in this region remains largely unknown. We analyzed 17 PFAAs in twelve coastal rivers of this region, and found staggeringly high concentrations of perfluorooctanoic acid (PFOA) ranging from 0.96 to 4534.41 ng/L. The highest concentration was observed in the Xiaoqing River which received effluents from certain fluoropolymer facilities. Principal component analysis indicated similar sources of several perfluoroalkyl carboxylic acids (PFCAs) in all rivers, which indicated that atmospheric transport, wastewater treatment and surface runoff also acted as important supplements to direct discharge to surface water. - Highlights: • PFAAs were detected in rapidly urbanized regions. • PFOA was found predominant followed by short chain PFCAs. • Fluoropolymer facilities were associated with PFAAs contamination. • Higher PFAAs levels were found near the PTFE production facilities. • Diffusion of PFAAs from rivers to the sea was influenced by tide and current. - High level of PFOA was detected in the river water due to the fluoropolymer industries in South Bohai coastal region

  8. 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.

  9. 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.

  10. Changes of oceanographic characteristics and the state of pollution in the Izmit bay following the earthquake of 1999

    Science.gov (United States)

    Morkoc, Enis; Tarzan, Legovic; Okay, Oya; Tufekci, Huseyin; Tufekci, Vildan; Tolun, Leyla; Karakoc, Fatma

    2007-09-01

    The Izmit Bay is an elongated semi-enclosed bay in the Marmara Sea. It is being increasingly polluted by both domestic and industrial waste discharge since 1970’s. A monitoring program was conducted between 1999-2000 to document the state of pollution in the bay. This includes the effect of Marmara (Izmit) earthquake (magnitude 7.4) that occurred in August 1999. A stable two-layer ecosystem exists in the bay throughout the year due to continuous inflows of the saltier Mediterranean and brackish Black Sea waters to the Marmara basin. Therefore, the principal biochemical characteristics of the bay are governed by the two-layer flow system over the basin. Dissolved oxygen (DO) is generally at a saturated levels in the surface layer which is 10 to 15 m thick, but it is depleted to 60-70 µM in the lower layer, exhibiting a steep gradient in the sharp halocline. When the earthquake occurred, great loads of industrial wastes were released into the bay surface waters, which enhanced primary production in the upper layer and thus large export of particulate organic matter to lower layer and eventually to the bottom. Accordingly, DO was consumed and anoxic condition was established even in the upper layer/halocline interface, the halocline and bottom waters of the eastern and central bay. In this period, concurrent increases were observed in phosphate and ammonia contents at the halocline and in deep waters whilst the nitrate was almost consumed via denitrification processes in the anoxic water. Recently, the industrial C, N and P loads increased by as much as 8 fold within five years (1995-2000) whilst domestic inputs increased by 50%. Total organic matter discharged to the bay increased more than double within the last 15 years. Besides, most factories in the region release toxic wastes into the bay after only partial treatment.

  11. Sedimentary phosphorus cycling and a phosphorus mass balance for the Green Bay (Lake Michigan) ecosystem

    Science.gov (United States)

    Val, Klump J.; Edgington, D.N.; Sager, P.E.; Robertson, D.M.

    1997-01-01

    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 ??mol??g-1. Deposition is highly focused, with ???0% 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. 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

  13. 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

  14. 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.

  15. 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.

    off. The hydrological imbalance thus created on an annual scale will have to be balanced by the inter-basin exchange. In winter this happens through the intrusion of Bay of Bengal waters into the Arabian Sea, when the southward flowing East India...

  16. Total arsenic in marine organisms from Cienfuegos Bay, Cuba

    International Nuclear Information System (INIS)

    Full text: Levels of total arsenic were determined in muscle tissues of species of finnish, crustaceans and molluscs from Cienfuegos Bay, Cuba. The arsenic contents in the samples were determined using an Energy Dispersive X Ray Fluorescence (EDXRF) method. The highest values of Total arsenic were found in crustaceans. Averages found for fish, crustaceans and molluscs were 10.2, 26.5 and 22 μg g-1 dry wt, respectively. These results are considered to be characteristic for normal or naturally altered areas. Cienfuegos Bay, situated in the Southern part of Cuba, is a semi-enclosed bay with a surface area of 90 km2 and an average depth of 14 m. It is connected to the Caribbean Sea by a narrow channel 3 km long. The bay is divided in two well defined hydrographic basins, due to the presence of a submerged ridge 1m below the surface. The Northern basin receives most of the anthropic impact from the outfall of Cienfuegos city (150,000 inhabitants), industrial pole in the country, and the freshwater input of Damuji and Salado rivers. The Southern basin is subjected to a smaller degree of anthropic pollution originating from the Caonao and Arimao rivers. Part of the Southern basin is a natural park, which represents a niche for protected migratory birds and marine species. The bay represents the most important natural resource in the province, due to fishing activities, maritime transport, tourism industry and natural parks. During the last decade it has acquired an important economic and social development, resulting in an increase of industrial and domestic wastes which are discharged into the bay. Direct input of Arsenic to Cienfuegos bay occurs through the Nitrogen Fertilizer Factory, which was authorized to release Arsenic residuals up to 1981 and where two accidental As spills took place in 1979 and 2001. Marine organisms represent an important component of the diet of the population of Cienfuegos. In particular, people from the coastal areas of Castillo de Jagua

  17. Total arsenic in marine organisms from Cienfuegos Bay, Cuba

    International Nuclear Information System (INIS)

    Full text: Levels of total arsenic were determined in muscle tissues of species of finnish, crustaceans and molluscs from Cienfuegos Bay, Cuba. The arsenic contents in the samples were determined using an Energy Dispersive X Ray Fluorescence (EDXRF) method. The highest values of Total arsenic were found in crustaceans. Averages found for fish, crustaceans and molluscs were 10.2, 26.5 and 22 μg g-1 dry wt, respectively. These results are considered to be characteristic for normal or naturally altered areas. Cienfuegos Bay, situated in the Southern part of Cuba, is a semi-enclosed bay with a surface area of 90 km2 and an average depth of 14 m. It is connected to the Caribbean Sea by a narrow channel 3 km long. The bay is divided in two well defined hydrographic basins, due to the presence of a submerged ridge 1m below the surface. The Northern basin receives most of the anthropic impact from the outfall of Cienfuegos city (150,000 inhabitants), industrial pole in the country, and the freshwater input of Damuji and Salado rivers. The Southern basin is subjected to a smaller degree of anthropic pollution originating from the Caonao and Arimao rivers. Part of the Southern basin is a natural park, which represents a niche for protected migratory birds and marine species. The bay represents the most important natural resource in the province, due to fishing activities, maritime transport, tourism industry and natural parks. During the last decade it has acquired an important economic and social development, resulting in an increase of industrial and domestic wastes which are discharged into the bay. Direct input of Arsenic to Cienfuegos bay occurs through the Nitrogen Fertilizer Factory, which was authorized to release Arsenic residuals up to 1981 and where two accidental As spills took place in 1979 and 2001. Marine organisms represent an important component of the diet of the population of Cienfuegos. In particular, people from the coastal areas of Castillo de Jagua

  18. 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, ...

  19. 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

  20. 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.

  1. 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...

  2. 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

  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. 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...

  5. With Prudhoe Bay in decline

    International Nuclear Information System (INIS)

    Almost every day, it seems, someone is mentioning Prudhoe Bay---its development activities, the direction of its oil production, and more recently its decline rate. Almost as frequently, someone is mentioning the number of companies abandoning exploration in Alaska. The state faces a double-edged dilemma: decline of its most important oil field and a diminished effort to find a replacement for the lost production. ARCO has seen the Prudhoe Bay decline coming for some time and has been planning for it. We have reduced staff, and ARCO and BP Exploration are finding cost-effective ways to work more closely together through such vehicles as shared services. At the same time, ARCO is continuing its high level of Alaskan exploration. This article will assess the future of Prudhoe Bay from a technical perspective, review ARCO's exploration plans for Alaska, and suggest what the state can do to encourage other companies to invest in this crucial producing region and exploratory frontier

  6. 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.

  7. 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)

  8. 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.

  9. 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.

  10. 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...

  11. 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

  12. 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

  13. 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 –...

  14. 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.

  15. 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.

  16. Understanding the flushing capability of Bellingham Bay and its implication on bottom water hypoxia

    Science.gov (United States)

    Wang, Taiping; Yang, Zhaoqing

    2015-11-01

    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 water residence time 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 water residence time in Bellingham Bay varies from near zero to as long as 15 days, depending on the location and river flow conditions. 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 to 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. Model results suggest that the formation of hypoxia in bottom water results from an enhanced oxygen consumption rate in the oceanic bottom water inflow with low dissolved oxygen by organic matters accumulated at the regions characterized with relatively long residence time in summer months.

  17. 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...

  18. 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

  19. 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

  20. 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

  1. 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.

  2. Observed characteristics of tide-surge interaction along the east coast of India and the head of Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Antony, C.; Unnikrishnan, A.S.

    reaches inside the river, the interaction effects changes and ζS+IST was less than ζS at all stages of the tide. Later, Johns et al. (1985) studied the tide-surge interaction in the Bay of Bengal by simulating two storm surge events that affected... of Bengal to that of the Arabian Sea is 4:1 (Niyas et al., 2009). In general, the cyclones in the bay are weak and short lived compared to those in other basins. The effects of cyclones become catastrophic due to the very large surges, they produce...

  3. 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

  4. 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.

  5. 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.

  6. Hydrodynamic numerical modelling of Maputo Bay

    OpenAIRE

    Canhanga, S.J.V.

    2003-01-01

    The aim of this work was to understand by using a numerical model, the main characteristics of the Maputo Bay hydrodynamics; and furthermore to assess the hydrodynamics implications on the different processes that can occur in the Bay. The study was initiated with a description of the hydrodynamical characteristics of Maputo Bay, through the analysis of vertical profiles of salinity and temperature, time series of the components of tide currents and water elevation. The wind intensity and ...

  7. 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...

  8. 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

  9. 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.

  10. 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....

  11. 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

  12. 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

  13. 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.

  14. 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.

  15. 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.

  16. 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. PMID:26363401

  17. 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.

  18. 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

  19. 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).

  20. 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

  1. Guangdong Daya Bay nuclear power station project

    International Nuclear Information System (INIS)

    Daya Bay Nuclear Power Station is the largest joint-venture project which is also the largest commercial nuclear power plant currently under construction in China mainland. Organized and executed strictly in accordance with international standards, the Daya Bay project is seen as the first step taken by China in the development programme of large-capacity commercial nuclear power units

  2. 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

  3. Bayes Estimation of Queue Length

    Czech Academy of Sciences Publication Activity Database

    Dohnal, Pavel

    Praha : ÚTIA AV ČR, 2006 - ( And rýsek, J.), s. 1-8 [International PhD Workshop on Interplay of Societal and Technical Decision-Making, Young Generation Viewpoint /7./. Hrubá Skála (CZ), 25.09.2006-30.09.2006] R&D Projects: GA MŠk 1M0572; GA AV ČR 1ET100750401 Institutional research plan: CEZ:AV0Z10750506 Keywords : Bayes estimation * queue length * traffic flow * occupancy * intensity Subject RIV: BC - Control Systems Theory

  4. 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.

  5. 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

  6. 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.

  7. 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...

  8. Prediction of the bioaccumulation of PAHs in surface sediments of Bohai Sea, China and quantitative assessment of the related toxicity and health risk to humans.

    Science.gov (United States)

    Li, Jiafu; Dong, Han; Xu, Xiang; Han, Bin; Li, Xianguo; Zhu, Chenjian; Han, Chen; Liu, Shaopeng; Yang, Dandan; Xu, Qian; Zhang, Dahai

    2016-03-15

    Assessing the health risk of PAHs in sediments was quite difficult because sediment occurred in sea floor, and it was very hard to contact with them directly for humans. This study was attempted to reveal the relationship between concentrations of PAHs in surface sediments and health risk of seafood consumers. The transfer (bioaccumulation) of PAHs from surface sediment into benthic organisms was predicted. Source contributions to PAHs and related toxicity and health risks (from intake of PAHs-contaminated benthic organisms) were studied based on PMF model and Monte Carlo simulation, respectively. Total concentrations of PAHs (TPAHs) ranged from 149.40 to 1211.97 ng g(-1) in sediments of Bohai Sea (BS), China. Petroleum and vehicular emission, coal combustion and coke oven constituted 40.0%, 32.2% and 27.8% of PAHs, respectively, but contributed 53.0%, 22.8% and 24.2% of toxicity posed by PAHs in sediment. For children, teens and adults, the 95th percentile carcinogenic and non-carcinogenic risks were below the threshold values of 10(-6) and 1.0, respectively, suggesting no potential health risk. Sensitivity analysis suggested that exposure duration (ED) and PAH concentrations (CS) were the two most sensitive parameters in risk assessment. The results provided a method to evaluate the quality of sediments and the potential health risk related to PAHs in marine sediments. PMID:26856644

  9. 渤海渔村剪纸文化内涵探究%Cultural Connotation of Paper-cutting in the Bohai Sea Fishing Village

    Institute of Scientific and Technical Information of China (English)

    药丽霞

    2012-01-01

    渤海渔村剪纸构图精美,剪纸作品体现出渔家妇女独特的审关情趣和心理诉求,其中所蕴含的文化内涵是很丰富的,具体表现为:祈求降福辟邪,家庭吉祥平安;祈求多子多福、人丁兴旺;祈求出海的亲人平安归来;宣示伦理道德,教育子孙后代;表达对美好生活的享受和热爱等。%The Paper-cutting of Bohai Sea Fishing Village is famous for its exquisite patterns, reflecting the unique aesthetic style and psychological demands of the fishing women. The works is also rich in cultural connotations, including a blessing to ward off evil, praying for peace and prosperity of the family, praying for flourishing offspring and the safe returning of relatives on the sea. All these culture elements express the idea of ethics education for future generations and love of life.

  10. Application of PMF receptor model merging with PAHs signatures for source apportionment of black carbon in the continental shelf surface sediments of the Bohai and Yellow Seas, China

    Science.gov (United States)

    Fang, Yin; Chen, Yingjun; Tian, Chongguo; Lin, Tian; Hu, Limin; Li, Jun; Zhang, Gan

    2016-02-01

    Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are byproducts generated from the incomplete combustion of organic materials, including fossil fuels and biomass. The similar production processes shared by BC and PAHs provide the possibility to infer the BC sources using the PAHs signatures. This study successfully utilized data sets of BC and PAHs analyzed from the continental shelf surface sediments of the Bohai and Yellow Seas to a standard receptor model of positive matrix factorization (PMF) to apportion the sources of BC in the sediment matrix. Results showed that combustion of fossil fuels (i.e., coal and oil/petroleum) accounted for an average level of 83 ± 5% of the total BC preserved, which was significantly higher than that from the biomass burning (17 ± 5%). The spatial distributions of the fossil BC concentrations and percentages differed significantly from those of the biomass BC, implying their different geochemical behaviors in the continental shelf regimes and further emphasizing the importance to effectively differentiate between fossil BC and biomass BC. In addition to the relative proportions of the BC subtypes (char-BC/soot-BC), the regional-specific hydrodynamic conditions, including the cold cyclonic eddy, resuspension and coastal current, also exerted a significant influence on these spatial variations.

  11. A semianalytical algorithm for quantitatively estimating sediment and atmospheric deposition flux from MODIS-derived sea ice albedo in the Bohai Sea, China

    Science.gov (United States)

    Xu, Zhantang; Hu, Shuibo; Wang, Guifen; Zhao, Jun; Yang, Yuezhong; Cao, Wenxi; Lu, Peng

    2016-05-01

    Quantitative estimates of particulate matter [PM) concentration in sea ice using remote sensing data is helpful for studies of sediment transport and atmospheric dust deposition flux. In this study, the difference between the measured dirty and estimated clean albedo of sea ice was calculated and a relationship between the albedo difference and PM concentration was found using field and laboratory measurements. A semianalytical algorithm for estimating PM concentration in sea ice was established. The algorithm was then applied to MODIS data over the Bohai Sea, China. Comparisons between MODIS derived and in situ measured PM concentration showed good agreement, with a mean absolute percentage difference of 31.2%. From 2005 to 2010, the MODIS-derived annual average PM concentration was approximately 0.025 g/L at the beginning of January. After a month of atmospheric dust deposition, it increased to 0.038 g/L. Atmospheric dust deposition flux was estimated to be 2.50 t/km2/month, similar to 2.20 t/km2/month reported in a previous study. The result was compared with on-site measurements at a nearby ground station. The ground station was close to industrial and residential areas, where larger dust depositions occurred than in the sea, but although there were discrepancies between the absolute magnitudes of the two data sets, they demonstrated similar trends.

  12. 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

  13. 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...

  14. Bayes reconstruction of missing teeth

    DEFF Research Database (Denmark)

    Sporring, Jon; Jensen, Katrine Hommelhoff

    2008-01-01

     We propose a method for restoring the surface of tooth crowns in a 3D model of a human denture, so that the pose and anatomical features of the tooth will work well for chewing. This is achieved by including information about the position and anatomy of the other teeth in the mouth. Our system...... contains two major parts: A statistical model of a selection of tooth shapes and a reconstruction of missing data. We use a training set consisting of 3D scans of dental cast models obtained with a laser scanner, and we have build a model of the shape variability of the teeth, their neighbors, and their...... regularization of the log-likelihood estimate based on differential geometrical properties of teeth surfaces, and we show general conditions under which this may be considered a Bayes prior.Finally we use Bayes method to propose the reconstruction of missing data, for e.g. finding the most probable shape of a...

  15. 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)

  16. 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

  17. 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.

  18. 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.

  19. A study on the spatial difference of farmland nitrogen nutrient budget in the Bohai Rim region, China%环渤海地区农田氮素养分收支空间差异研究

    Institute of Scientific and Technical Information of China (English)

    GUO Liying; YANG Ren; WANG Daolong

    2012-01-01

    @@%The Bohai Rim region is one the most important bases for commodity grain production in China.With the rapid pace of agricultural industrialization,nitrogenous fertilizer has been used at an ever increasing rate,which resulted in the trace of accumulative nitrogen in the soil and caused serious environmental problems.In this study we made use of the farmland nitrogen balance model to assess the spatial difference of farmland nitrogen nutrient budget in the Bohai Rim region in 2008 with the assistance of GIS.Our results indicated that:1) Farmland in this region has a nitrogen surplus totaling 5.0822 million tons,or an average of 288.54 kg/ha.2) In the Bohai Rim region,farmland nitrogen input and farmland nitrogen budget both show a spatial differentiation.Major grain-producing areas have a higher nitrogen input than that of the grazing-farming areas.The main sources of nitrogen input include chemical fertilizer,organic fertilizer,deposition from atmospheric drying and wetting,and biological fixation,which account for 79.47%,9.53%,4.62%,and 3.58% of the total input,respectively.Therefore,chemical fertilizer is the predominant source of nitrogen input to farmland.3) A total of 3.3398 million tons of nitrogen were output from the farmland via harvested crops and it accounts for 52.36% of the total nitrogen output from farmland in this region.On average,the amount of nitrogen output from unit farmland is equal to 176.65kg/ha.This study has shed light on farmland nitrogen budget and its spatial variation in the study area,may provide scientific evidences for rationalizing the use of chemical fertilizer and managing agricultural operation on the regional scale and is also valuable for improving the economic and ecological efficiency of fertilizer use at the regional scale.

  20. Spatiotemporal distribution characteristics of low-level jet over Bohai Sea rim%环渤海地区低空急流的时空分布特征

    Institute of Scientific and Technical Information of China (English)

    赛瀚; 苗峻峰

    2012-01-01

    利用2008年环渤海地区常规探空资料对该地区低空急流的时空分布特征进行了统计分析。结果表明:环渤海地区的低空急流属于中尺度低空急流,东北部(辽东半岛)出现低空急流的次数最多,其次是西北部,最少的是南部(山东半岛);环渤海地区低空急流出现的等压面较低,主要出现在925hPa和850hPa上;低空急流季节变化明显,春季出现最多,秋、冬季次之,夏季较少;它的平均风速为15-16m/s,风向以SW向为主,其次是NW向,大多出现在1500-1600m和700-950m的高度上。平均速度的大值一般出现在冬季,而冬季对应的平均高度是最低的;在夏季出现的低空急流的速度最小,而高度最高。%Statistical characteristics of low-level jet (LLJ) were analyzed using conventional NOAA/ESRL radio- sonde data of Beijing, Chifeng, Shenyang, Dalian, Zhangqiu in 2008 over Bohai Sea rim in this paper. Results show that the scale of LLJ over Bohai Sea rim is meso-scale. It can be geographically divided into three types : the highest occurrence of LLJ is at the northeast of Bohai Sea rim ( Liaodong Peninsula), followed by the northwest, and the least at the south ( Shandong Peninsula). The main occurring height of LL.I in this area is at 925 hPa and 850 hPa levels. LLJ over Bohai Sea rim exhibits evident Seasonal variation. It occurs most in spring, followed by autumn and winter, and the least in summer. The mean wind speed of LLJ is mainly around 15 - 16 m/s, the wind direction of LLJ is predominately from SW and NW, and the height of LLJ is around 1 500 - 1 600 m and 700 - 950 m. The LLJ with large (small) average speed corresponds to a low (high) average height in winter (summer).

  1. 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...

  2. 33 CFR 334.762 - Naval Support Activity Panama City; North Bay and West Bay; restricted areas.

    Science.gov (United States)

    2010-07-01

    ... City; North Bay and West Bay; restricted areas. 334.762 Section 334.762 Navigation and Navigable Waters... REGULATIONS § 334.762 Naval Support Activity Panama City; North Bay and West Bay; restricted areas. (a) The... occurring within the active military security zone/s and offering navigational advice to ensure the...

  3. 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 ...

  4. 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)

  5. 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...

  6. Holy grail at Baglan Bay

    International Nuclear Information System (INIS)

    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)

  7. Measuring the Carolina Bays Using Archetype Template Overlays on the Google Earth Virtual Globe; Planform Metrics for 25,000 Bays Extracted from LiDAR and Satellite Imagery

    Science.gov (United States)

    Davias, M. E.; Gilbride, J. L.

    2011-12-01

    Aerial photographs of Carolina bays taken in the 1930's sparked the initial research into their geomorphology. Satellite Imagery available today through the Google Earth Virtual Globe facility expands the regions available for interrogation, but reveal only part of their unique planforms. Digital Elevation Maps (DEMs), using Light Detection And Ranging (LiDAR) remote sensing data, accentuate the visual presentation of these aligned ovoid shallow basins by emphasizing their robust circumpheral rims. To support a geospatial survey of Carolina bay landforms in the continental USA, 400,000 km2 of hsv-shaded DEMs were created as KML-JPEG tile sets. A majority of these DEMs were generated with LiDAR-derived data. We demonstrate the tile generation process and their integration into Google Earth, where the DEMs augment available photographic imagery for the visualization of bay planforms. While the generic Carolina bay planform is considered oval, we document subtle regional variations. Using a small set of empirically derived planform shapes, we created corresponding Google Earth overlay templates. We demonstrate the analysis of an individual Carolina bay by placing an appropriate overlay onto the virtually globe, then orientating, sizing and rotating it by edit handles such that it satisfactorily represents the bay's rim. The resulting overlay data element is extracted from Google Earth's object directory and programmatically processed to generate metrics such as geographic location, elevation, major and minor axis and inferred orientation. Utilizing a virtual globe facility for data capture may result in higher quality data compared to methods that reference flat maps, where geospatial shape and orientation of the bays could be skewed and distorted in the orthographic projection process. Using the methodology described, we have measured over 25k distinct Carolina bays. We discuss the Google Fusion geospatial data repository facility, through which these data have been

  8. 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

  9. Geophysical surveys around the Izmir Bay

    Science.gov (United States)

    Aykut, Tunçel; Tolga, Gönenç; Mustafa, Akgün; Oya, Pamukcu; Özkan, Özdağ; Mehmet, Çetiner

    2015-04-01

    Izmir is the 3rd largest city of Turkey following Istanbul and Ankara in terms of population, industrial density and contribution to the national economy. Izmir city is located very close to the active faults, has very high seismic risk and develops rapidly on thick and Quaternary-Neogene aged young sediments. Three different tectonic belts take place in Izmir precincts. One of these belts which shapes the Menderes massif at east consists of very thick mica schist unit at basement and a marble stack which formed by the metamorphism of the platform type carbonates. Another tectonic belt named "Izmir-Ankara zone" take place at western part of massif and around Izmir city there is another tectonic belt which is generally flysch characterized. "Karaburun Belt" is at west of "Izmir-Ankara zone" comprised by a thick Mesozoic carbonate stack which precipitated at platform conditions. Izmir and its surroundings, has been the scene of intense earthquake activity since the historical period. The most of earthquake epicenters are at Aegean Sea and take place between Karaburun-Chios Island, Izmir Bay-Lesbos Island and Doğanbey Cape-Samos Island. A number of earthquakes occurs on the remaining land mass between the Aegean Sea and the western part of the Gediz graben. Izmir city to be the center of the 50-60 km radius, there are active faults that may pose a risk by generating potential earthquakes for Izmir metropolitan area and its surroundings. Propagation of earthquake waves towards to surface can be affected considerably by unconsolidated soil structures of Izmir. While occurrence of shallow and large scaled earthquakes, mechanism of soil amplification, liquefaction in sandy soils and losses of bearing capacity in clayey soil can be expected that they are particularly effective on earthquake performance of both buildings and industrial areas. Also some conditions such as; physical parameters of alluvial soil, high groundwater level and basin geometry, which cause soil

  10. Mixed layer variability and chlorophyll a biomass in the Bay of Bengal

    OpenAIRE

    J. Narvekar; Prasanna Kumar, S.

    2013-01-01

    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 chlorophyll concentration. In this paper we examined the seasonal variability of the mixed layer depth in the Bay of Bengal, the factors responsible for it and the coupling of mixed layer processes to the chlorophyll biomass using a suite of in situ as well as remote sensing data. The basin-wide mixed layer de...

  11. Natural isotopic composition of nitrogen in suspended particulate matter in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Kumar, S.; Ramesh, R.; Bhosle, N.B.; Sardessai, S.; Sheshshayee, M.S.

    which the study was performed during both seasons. Major rivers draining into the Bay of Bengal are also shown. Dots are the stations. 2 Material and methods Sampling was performed along the cruise track shown in Fig. 1, onboard ORV Sagar Kanya, as a..., 1993) from the major rivers draining the Indian subcontinent. This fresh- water input results in considerable salinity variations dur- ing and after the monsoon over the whole basin, thereby inducing stratification of the upper 100m of the water col...

  12. Efforts Stepped up to Curb Offshore Oil Pollution

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    China's oil sector has established the Bohai Sea Offshore Oil Environmental Protection Company to tackle worsening oil leakage pollution in north China's Bohai Sea. The bay of the Bohai Sea has been experiencing extensive offshore oil production and the oil turnover in Tianjin Port has been increasing fast, an expert with the company said.

  13. 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.

  14. 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...

  15. Bathymetry--Offshore Half Moon Bay, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the bathymetry and shaded-relief maps of the Offshore Half Moon Bay, California (raster data file is included in...

  16. 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...

  17. San Antonio Bay 1986-1989

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The effect of salinity on utilization of shallow-water nursery habitats by aquatic fauna was assessed in San Antonio Bay, Texas. Overall, 272 samples were collected...

  18. 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.

  19. 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...

  20. 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...

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. Willapa Bay, Washington Benthic Habitats 1995 Biotic

    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...

  6. Willapa Bay, Washington Benthic Habitats 1995 Geoform

    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...

  7. 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...

  8. 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...

  9. 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,...

  10. 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...

  11. Bay Scallop Spawning, Survival, Growth Records

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Bay Scallops are selected and cultured according to criteria of growth and survival. Morphological attributes have also been selected to assess heretibility....

  12. San Francisco Bay Water Quality Improvement Fund

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Water Quality Improvement Fund is a competitive grant program that is helping implement TMDLs to improve water quality, protect wetlands, and...

  13. 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...

  14. Bayes Factors via Savage-Dickey Supermodels

    CERN Document Server

    Mootoovaloo, A; Kunz, M

    2016-01-01

    We outline a new method to compute the Bayes Factor for model selection which bypasses the Bayesian Evidence. Our method combines multiple models into a single, nested, Supermodel using one or more hyperparameters. Since the models are now nested the Bayes Factors between the models can be efficiently computed using the Savage-Dickey Density Ratio (SDDR). In this way model selection becomes a problem of parameter estimation. We consider two ways of constructing the supermodel in detail: one based on combined models, and a second based on combined likelihoods. We report on these two approaches for a Gaussian linear model for which the Bayesian evidence can be calculated analytically and a toy nonlinear problem. Unlike the combined model approach, where a standard Monte Carlo Markov Chain (MCMC) struggles, the combined-likelihood approach fares much better in providing a reliable estimate of the log-Bayes Factor. This scheme potentially opens the way to computationally efficient ways to compute Bayes Factors in...

  15. 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...

  16. 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.

  17. 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...

  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. The Daya Bay Reactor Neutrino Experiment

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    On Aug.15, 201l, a new large-scale scientific facility in China, Daya Bay Reactor Neutrino Experiment, started to operate. It is located in Daya Bay Nuclear Power Plant in Guangdong Province, around 50kin to both Hong Kong and Shenzhen City. The main scientific goal is to precisely determine the neutrino mixing angle 013 by detecting neutrinos from the reactors at different distances.

  20. New constraints on the crustal structure in the eastern part of northern Baffin Bay

    Science.gov (United States)

    Reichert, C. J.; Damm, V.; Altenbernd, T.; Berglar, K.; Block, M.; Ehrhardt, A.; Schnabel, M.

    2010-12-01

    The northern Baffin Bay is a key area for testing plate kinematic models for the Paleocene-Eocene motion of Greenland relative to North America and to decipher the evolution of the thick sedimentary basins in this area. In summer 2010, a multidisciplinary marine geoscientific expedition focusing on the Greenland part of northern Baffin Bay was performed under the direction of the Federal Institute for Geosciences and Natural Resources Hannover, Germany in cooperation with the Alfred-Wegener Institute Bremerhaven. Using 70 days ship time onboard the German R/V Polarstern a comprehensive data set was acquired along profiles extending from the deep oceanic basin in the central part of North Baffin Bay onto the Greenland continental margin in an area which was bordered by the Kane Basin in the North and Disco Island in the South. By means of multi-channel seismic, wide angle seismic, gravimetric and magnetic methods the structural inventory of the crust in the NW Baffin Bay was investigated. Additionally, heat flow data and sediment cores were collected at selected positions along lines across the Greenland continental margin. The cores were extracted for geochemical and geomicrobiological analysis to be used for basin modeling and studying the hydrocarbon potential. Aeromagnetic data was acquired covering part of the marine survey area to investigate magnetic signatures of the oceanic crust and the continental margin. In our presentation we will give an overview of the first results of the expedition with special focus on multi-channel seismic data. With a total length of 3500 km, the initial interpretation of multi-channel seismic data shows that the West Greenland margin is a typical passive continental margin with large rotated basement blocks, listric faults facing mainly seaward, and deep syn-rift-basins in between. The most prominent reflector under the shelf and the slope probably indicates the transition from rifting to drifting and therefore the beginning of

  1. Deriving Chesapeake Bay Water Quality Standards

    Science.gov (United States)

    Tango, Peter J.; Batiuk, Richard A.

    2013-01-01

    Achieving and maintaining the water quality conditions necessary to protect the aquatic living resources of the Chesapeake Bay and its tidal tributaries has required a foundation of quantifiable water quality criteria. Quantitative criteria serve as a critical basis for assessing the attainment of designated uses and measuring progress toward meeting water quality goals of the Chesapeake Bay Program partnership. In 1987, the Chesapeake Bay Program partnership committed to defining the water quality conditions necessary to protect aquatic living resources. Under section 303(c) of the Clean Water Act, States and authorized tribes have the primary responsibility for adopting water quality standards into law or regulation. The Chesapeake Bay Program partnership worked with U.S. Environmental Protection Agency to develop and publish a guidance framework of ambient water quality criteria with designated uses and assessment procedures for dissolved oxygen, water clarity, and chlorophyll a for Chesapeake Bay and its tidal tributaries in 2003. This article reviews the derivation of the water quality criteria, criteria assessment protocols, designated use boundaries, and their refinements published in six addendum documents since 2003 and successfully adopted into each jurisdiction's water quality standards used in developing the Chesapeake Bay Total Maximum Daily Load.

  2. Gradient Analysis and Classification of Carolina Bay Vegetation: A Framework for Bay Wetlands Conservation and Restoration

    Energy Technology Data Exchange (ETDEWEB)

    Diane De Steven,Ph.D.; Maureen Tone,PhD.

    1997-10-01

    This report address four project objectives: (1) Gradient model of Carolina bay vegetation on the SRS--The authors use ordination analyses to identify environmental and landscape factors that are correlated with vegetation composition. Significant factors can provide a framework for site-based conservation of existing diversity, and they may also be useful site predictors for potential vegetation in bay restorations. (2) Regional analysis of Carolina bay vegetation diversity--They expand the ordination analyses to assess the degree to which SRS bays encompass the range of vegetation diversity found in the regional landscape of South Carolina's western Upper Coastal Plain. Such comparisons can indicate floristic status relative to regional potentials and identify missing species or community elements that might be re-introduced or restored. (3) Classification of vegetation communities in Upper Coastal Plain bays--They use cluster analysis to identify plant community-types at the regional scale, and explore how this classification may be functional with respect to significant environmental and landscape factors. An environmentally-based classification at the whole-bay level can provide a system of templates for managing bays as individual units and for restoring bays to desired plant communities. (4) Qualitative model for bay vegetation dynamics--They analyze present-day vegetation in relation to historic land uses and disturbances. The distinctive history of SRS bays provides the possibility of assessing pathways of post-disturbance succession. They attempt to develop a coarse-scale model of vegetation shifts in response to changing site factors; such qualitative models can provide a basis for suggesting management interventions that may be needed to maintain desired vegetation in protected or restored bays.

  3. Detrital zircon and apatite fission track data in the Liaoxi basins: Implication to Meso-Cenozoic thermo-tectonic evolution of the northern margin of the North China Craton

    Indian Academy of Sciences (India)

    Yi Yan; Xiaoqiong Hu; Ge Lin; Weiliang Liu; Zhengjiang Song

    2010-08-01

    Detrital zircon and apatite fission track (ZFT and AFT) data of the sandstones collected from the Liaoxi basins served as a significant probe to study the Meso-Cenozoic thermo-tectonic reactivation events in the northern margin of the North China Craton. All sandstones show wide ZFT and AFT age spectrum and most of ZFT and AFT ages are younger than depositional age of respective host rocks, which suggest widespread track resetting of the host rocks in the Liaoxi basins after deposition. This hot geothermal status in the Liaoxi basins deduced from ZFT and AFT data is temporal consistent with the lithospheric evolution of the North China Craton, which implies that the lithosphere under the northern margin of the North China Craton underwent similar thermo-tectonic destruction process as the intracratonic Bohai Sea. The young ZFT peak age, which ranges from ∼50Ma to 20 Ma, to some extend, provides a temporal constraint on the time that lithosphere significantly thinned and following reverse of the Liaoxi basins and uplift of the eastern part of the Yan-Liao Orogenic Belt. Exhumation of 1.5–2 km can be estimated in the eastern part of the Yan-Liao Orogenic Belt since ∼30Ma to 10 Ma.

  4. Postimpact deposition in the Chesapeake Bay impact structure: Variations in eustasy, compaction, sediment supply, and passive-aggressive tectonism

    Science.gov (United States)

    Kulpecz, A.A.; Miller, K.G.; Browning, J.V.; Edwards, L.E.; Powars, D.S.; McLaughlin, P.P., Jr.; Harris, A.D.; Feigenson, M.D.

    2009-01-01

    The Eyreville and Exmore, Virginia, core holes were drilled in the inner basin and annular trough, respectively, of the Chesapeake Bay impact structure, and they allow us to evaluate sequence deposition in an impact crater. We provide new high-resolution geochronologic (<1 Ma) and sequence-stratigraphic interpretations of the Exmore core, identify 12 definite (and four possible) postimpact depositional sequences, and present comparisons with similar results from Eyreville and other mid- Atlantic core holes. The concurrence of increases in ??18O with Chesapeake Bay impact structure sequence boundaries indicates a primary glacioeustatic control on deposition. However, regional comparisons show the differential preservation of sequences across the mid-Atlantic margin. We explain this distribution by the compaction of impactites, regional sediment-supply changes, and the differential movement of basement structures. Upper Eocene strata are thin or missing updip and around the crater, but they thicken into the inner basin (and offshore to the southeast) due to rapid crater infilling and concurrent impactite compaction. Oligocene sequences are generally thin and highly dissected throughout the mid-Atlantic region due to sediment starvation and tectonism, except in southeastern New Jersey. Regional tectonic uplift of the Norfolk Arch coupled with a southward decrease in sediment supply resulted in: (1) largely absent Lower Miocene sections around the Chesapeake Bay impact structure compared to thick sections in New Jersey and Delaware; (2) thick Middle Miocene sequences across the Delmarva Peninsula that thin south of the Chesapeake Bay impact structure; and (3) upper Middle Miocene sections that pinch out just north of the Chesapeake Bay impact structure. Conversely, the Upper Miocene-Pliocene section is thick across Virginia, but it is poorly represented in New Jersey because of regional variations in relative subsidence. ?? 2009 The Geological Society of America.

  5. Melo carboniferous basin

    International Nuclear Information System (INIS)

    This report is about of the Melo carboniferous basin which limits are: in the South the large and high Tupambae hill, in the west the Paraiso hill and the river mountains, in the North Yaguaron river basin to Candidata in Rio Grande del Sur in Brazil.

  6. 77 FR 39420 - Safety Zone; Bay Village Independence Day Fireworks, Lake Erie, Bay Village, OH

    Science.gov (United States)

    2012-07-03

    ...: Table of Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Village Independence Day Fireworks... intended to restrict vessels from a portion of Lake Erie during the Bay Village Independence Day...

  7. BOOK REVIEW OF "CHESAPEAKE BAY BLUES: SCIENCE, POLITICS, AND THE STRUGGLE TO SAVE THE BAY"

    Science.gov (United States)

    This is a book review of "Chesapeake Bay Blues: Science, Politics, and the Struggle to Save the Bay". This book is very well written and provides an easily understandable description of the political challenges faced by those proposing new or more stringent environmental regulat...

  8. K Basin safety analysis

    International Nuclear Information System (INIS)

    The purpose of this accident safety analysis is to document in detail, analyses whose results were reported in summary form in the K Basins Safety Analysis Report WHC-SD-SNF-SAR-001. The safety analysis addressed the potential for release of radioactive and non-radioactive hazardous material located in the K Basins and their supporting facilities. The safety analysis covers the hazards associated with normal K Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. After a review of the Criticality Safety Evaluation of the K Basin activities, the following postulated events were evaluated: Crane failure and casks dropped into loadout pit; Design basis earthquake; Hypothetical loss of basin water accident analysis; Combustion of uranium fuel following dryout; Crane failure and cask dropped onto floor of transfer area; Spent ion exchange shipment for burial; Hydrogen deflagration in ion exchange modules and filters; Release of Chlorine; Power availability and reliability; and Ashfall

  9. K Basin safety analysis

    Energy Technology Data Exchange (ETDEWEB)

    Porten, D.R.; Crowe, R.D.

    1994-12-16

    The purpose of this accident safety analysis is to document in detail, analyses whose results were reported in summary form in the K Basins Safety Analysis Report WHC-SD-SNF-SAR-001. The safety analysis addressed the potential for release of radioactive and non-radioactive hazardous material located in the K Basins and their supporting facilities. The safety analysis covers the hazards associated with normal K Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. After a review of the Criticality Safety Evaluation of the K Basin activities, the following postulated events were evaluated: Crane failure and casks dropped into loadout pit; Design basis earthquake; Hypothetical loss of basin water accident analysis; Combustion of uranium fuel following dryout; Crane failure and cask dropped onto floor of transfer area; Spent ion exchange shipment for burial; Hydrogen deflagration in ion exchange modules and filters; Release of Chlorine; Power availability and reliability; and Ashfall.

  10. Bayes and empirical Bayes iteration estimators in two seemingly unrelated regression equations

    Institute of Scientific and Technical Information of China (English)

    WANG; Lichun

    2005-01-01

    For a system of two seemingly unrelated regression equations given by {y1=X1β+ε1,y2=X2γ+ε2, (y1 is an m × 1 vector and y2 is an n × 1 vector, m≠ n), employing the covariance adjusted technique, we propose the parametric Bayes and empirical Bayes iteration estimator sequences for regression coefficients. We prove that both the covariance matrices converge monotonically and the Bayes iteration estimator squence is consistent as well. Based on the mean square error (MSE) criterion, we elaborate the superiority of empirical Bayes iteration estimator over the Bayes estimator of single equation when the covariance matrix of errors is unknown. The results obtained in this paper further show the power of the covariance adjusted approach.

  11. Bayes and empirical-Bayes multiplicity adjustment in the variable-selection problem

    CERN Document Server

    Scott, James G; 10.1214/10-AOS792

    2010-01-01

    This paper studies the multiplicity-correction effect of standard Bayesian variable-selection priors in linear regression. Our first goal is to clarify when, and how, multiplicity correction happens automatically in Bayesian analysis, and to distinguish this correction from the Bayesian Ockham's-razor effect. Our second goal is to contrast empirical-Bayes and fully Bayesian approaches to variable selection through examples, theoretical results and simulations. Considerable differences between the two approaches are found. In particular, we prove a theorem that characterizes a surprising aymptotic discrepancy between fully Bayes and empirical Bayes. This discrepancy arises from a different source than the failure to account for hyperparameter uncertainty in the empirical-Bayes estimate. Indeed, even at the extreme, when the empirical-Bayes estimate converges asymptotically to the true variable-inclusion probability, the potential for a serious difference remains.

  12. Hierarchical Bayes Ensemble Kalman Filtering

    CERN Document Server

    Tsyrulnikov, Michael

    2015-01-01

    Ensemble Kalman filtering (EnKF), when applied to high-dimensional systems, suffers from an inevitably small affordable ensemble size, which results in poor estimates of the background error covariance matrix ${\\bf B}$. The common remedy is a kind of regularization, usually an ad-hoc spatial covariance localization (tapering) combined with artificial covariance inflation. Instead of using an ad-hoc regularization, we adopt the idea by Myrseth and Omre (2010) and explicitly admit that the ${\\bf B}$ matrix is unknown and random and estimate it along with the state (${\\bf x}$) in an optimal hierarchical Bayes analysis scheme. We separate forecast errors into predictability errors (i.e. forecast errors due to uncertainties in the initial data) and model errors (forecast errors due to imperfections in the forecast model) and include the two respective components ${\\bf P}$ and ${\\bf Q}$ of the ${\\bf B}$ matrix into the extended control vector $({\\bf x},{\\bf P},{\\bf Q})$. Similarly, we break the traditional backgrou...

  13. Physical processes in a coupled bay-estuary coastal system: Whitsand Bay and Plymouth Sound

    Science.gov (United States)

    Uncles, R. J.; Stephens, J. A.; Harris, C.

    2015-09-01

    Whitsand Bay and Plymouth Sound are located in the southwest of England. The Bay and Sound are separated by the ∼2-3 km-wide Rame Peninsula and connected by ∼10-20 m-deep English Channel waters. Results are presented from measurements of waves and currents, drogue tracking, surveys of salinity, temperature and turbidity during stratified and unstratified conditions, and bed sediment surveys. 2D and 3D hydrodynamic models are used to explore the generation of tidally- and wind-driven residual currents, flow separation and the formation of the Rame eddy, and the coupling between the Bay and the Sound. Tidal currents flow around the Rame Peninsula from the Sound to the Bay between approximately 3 h before to 2 h after low water and form a transport path between them that conveys lower salinity, higher turbidity waters from the Sound to the Bay. These waters are then transported into the Bay as part of the Bay-mouth limb of the Rame eddy and subsequently conveyed to the near-shore, east-going limb and re-circulated back towards Rame Head. The Simpson-Hunter stratification parameter indicates that much of the Sound and Bay are likely to stratify thermally during summer months. Temperature stratification in both is pronounced during summer and is largely determined by coastal, deeper-water stratification offshore. Small tidal stresses in the Bay are unable to move bed sediment of the observed sizes. However, the Bay and Sound are subjected to large waves that are capable of driving a substantial bed-load sediment transport. Measurements show relatively low levels of turbidity, but these respond rapidly to, and have a strong correlation with, wave height.

  14. Wada basin boundaries and basin cells

    NARCIS (Netherlands)

    Nusse, H.E.; Yorke, J.A.

    1996-01-01

    In dynamical systems examples are common in which two or more attractors coexist, and in such cases the basin boundary is nonempty. We consider a two-dimensional diffeomorphism F (that is, F is an invertible map and both F and its inverse are differentiable with continuous derivatives), which has at

  15. Characterizing benthic substrates of Santa Monica Bay with seafloor photography and multibeam sonar imagery.

    Science.gov (United States)

    Edwards, Brian D; Dartnell, Peter; Chezar, Henry

    2003-01-01

    Seafloor photography from three cruises is combined with multibeam sonar imagery to characterize benthic substrates and associated fauna of Santa Monica Bay, California. The multibeam EM1000 imagery was collected in 1996. Two sampling cruises (in 1998 and 1999) provided photographs at 142 sites throughout the Bay; a final cruise (in 2000) collected still photographs and continuous video along nine transects on the mainland shelf from Pt. Dume to the Palos Verdes peninsula. Muddy substrates (typically low backscatter) were the predominant habitat throughout the Santa Monica Bay, from the 20 m isobath to the adjacent Santa Monica basin floor (780 m). Bioturbation was pervasive as evidenced by abundant open burrows, mounds, and faunal tracks and trails. Sandy substrates (typically intermediate to high backscatter) were restricted to the innermost mainland shelf and a narrow outer shelf band north of Santa Monica Canyon. Cobble and gravel substrates (high backscatter) were restricted to the innermost shelf south of El Segundo and limited parts of the shelf edge. Rocky substrates (high backscatter) with interspersed patches of sand and gravel occurred on the high-relief marginal plateau and along parts of the shelf break offshore of Malibu. PMID:12648949

  16. Genotoxicity of surface water samples from Meiliang Bay, Taihu Lake, Eastern China.

    Science.gov (United States)

    Shen, L; Lin, G F; Tan, J W; Shen, J H

    2000-07-01

    Taihu Lake is the third largest freshwater lake in China. Taihu Basin is one of the most densely populated and urbanized areas in this country. This area provides 15% of the GDP. Meiliang Bay is located in the north part of the Lake. It provides the municipal water source for Wuxi City. Some parts of the lake have been found to be highly polluted due to eutrophication for over a decade. Surface water (0-0.5 m) samples were collected from the Meiliang Bay by the aid of Global Position System (GPS) for positioning. Water samples were concentrated 5000 times with XAD-2 resin columns. A reverse mutation test using histidine-dependent Salmonella typhimurium strains was employed to assay the genotoxicity of the samples. The results showed that the sample from position 6 had the highest genotoxicity either in the case of activating with eucaryotic S9 system or without S9. The genotoxic effect included, at least, two different molecular mechanisms: nucleotide point substitution on DNA molecules and reading frame shifting caused by nucleotide insertion or deletion. The genotoxicity of the water body in Meiliang Bay, Taihu Lake should be kept in close monitoring. PMID:10819189

  17. Application of PowerDrive VorteX Rotary Steering Drilling System in Bohai Bay%vo rteX 型动力导向钻井系统在渤海油田的应用

    Institute of Scientific and Technical Information of China (English)

    付建民; 韩雪银; 马英文; 王佳; 冉宏应

    2014-01-01

    为解决渤海油田深井和大位移井钻井中机械钻速慢、井下故障频发等问题,优选并试验应用了vorteX型动力导向钻井系统。该钻井系统由M WD/LWD、大扭矩井下动力总成、Filter+ Flex总成、旋转导向系统等部件组成,由顶驱系统与动力总成复合驱动下的钻头高速旋转来实现破岩,由C-Link以电磁短程通讯方式完成旋转导向系统与M WD之间的信号双向传输,再经M WD完成电信号与钻井液脉冲信号间的转换后,实现与地面收发装置间的信号双向传输。现场应用表明,该系统的总动力达到133~257 kW ,机械钻速可提高30.34%~205.06%;最大工作负荷由45kN·m降至36kN·m ,理论磨损值降至原来的1/4;日平均进尺由74m提高至160m ,节省工期153 d ,折算费用1亿5300万元。由此可知,vorteX动力导向钻井系统是旋转导向工具与大扭矩井下动力总成的有效结合,适用于深井与大位移井钻井,能显著提高机械钻速,减少井下故障的发生。%To address the problems encountered in deep well and extended reach well drilling such as low ROP and frequent severe accidents ,drilling tools research and selection were conducted and PowerDrive vorteX rotary steering system was selected .The PowerDrive vorteX rotary steering system consists of MWD/LWD , high-torque power section ,Filter+ Flex assembly and rotary steering components .Safe drilling was achieved by a high-speed bit driven by both top drive and power section of PowerDrive vorteX .Electromagnetic short-range communication method was used by C-Link in bi-direction signal transmission between rotary steering system and MWD .Electricalsignals and mud pulse signals were then transformed in MWD ,and mud pulse was used in bi-direction signal transmission between MWD and surface transmitter-receiver set .Field application showed that the rotary steering system ,with a total power of 133 -257 kW ,made a ROP improvement of 30.34% -205.06% ,a maximum workload reduction from 45 kN · m to 36 kN · m ,a friction reduction of 75% ,an daily average footage improvement from 74 m to 160 m ,saving 153 days of rig time which reduced costs up to 153 million RMB .Therefore ,the PowerDrive vorteX rotary steering system ,which effectively integrated rotary steering and high-torque power section ,is preferable for deep well and extended reach well drilling and can sig-nificantly improve ROP and reduce down hole failure .

  18. Reserves in western basins

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, R.H.; Cotton, B.W. [Scotia Group, Dallas, TX (United States)

    1995-04-01

    The objective of this project is to investigate the reserves potential of tight gas reservoirs in three Rocky Mountain basins: the Greater Green River (GGRB), Uinta and Piceance basins. The basins contain vast gas resources that have been estimated in the thousands of Tcf hosted in low permeability clastic reservoirs. This study documents the productive characteristics of these tight reservoirs, requantifies gas in place resources, and characterizes the reserves potential of each basin. The purpose of this work is to promote understanding of the resource and to encourage its exploitation by private industry. At this point in time, the GGRB work has been completed and a final report published. Work is well underway in the Uinta and Piceance basins which are being handled concurrently, with reports on these basins being scheduled for the middle of this year. Since the GGRB portion of the project has been completed, this presentation win focus upon that basin. A key conclusion of this study was the subdivision of the resource, based upon economic and technological considerations, into groupings that have distinct properties with regard to potential for future producibility, economics and risk profile.

  19. Mixed layer variability and chlorophyll a biomass in the Bay of Bengal

    Directory of Open Access Journals (Sweden)

    J. Narvekar

    2013-10-01

    Full Text Available 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 chlorophyll concentration. In this paper we examined the seasonal variability of the mixed layer depth in the Bay of Bengal, the factors responsible for it and the coupling of mixed layer processes to the chlorophyll biomass using a suite of in situ as well as remote sensing data. The basin-wide mixed layer depth was the shallowest during spring intermonsoon, which was associated with strong themohaline stratification of the upper water column. The prevailing winds which were the weakest of all the seasons were unable to break the stratification leading to the observed shallow mixed layer. Consistent with the warm oligotrophic upper ocean, the surface chlorophyll concentrations were the least and the vertical profile of chlorophyll was characterized by a subsurface chlorophyll maximum. Similarly, during summer though the monsoon winds were the strongest they were unable to break the upper ocean haline-stratification in the northern Bay brought about by a combination of excess precipitation over evaporation and fresh water influx from rivers adjoining the Bay of Bengal. Consistent with this though the nitrate concentrations were high in the northern part of the Bay, the chlorophyll concentrations were low indicating the light limitation. In contrast, in the south, advection of high salinity waters from the Arabian Sea coupled with the westward propagating Rossby waves of annual periodicity were able to decrease stability of the upper water column and the prevailing monsoon winds were able to initiate deep mixing leading to the observed deep mixed layer. The high chlorophyll concentration observed in the south resulted from the positive wind stress curl which pumped nutrient rich subsurface waters to the euphotic zone. The southward extension of the shallow mixed

  20. Study on Basin-Filling and Reservoir Sedimentology of Zhu Ⅲ Depression of Pearl River Mouth Basin, South China Sea

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Through basin-filling analysis, one coarsening-upward and two fining-upward sequences have been identified in Zhu Ⅲ depression. In accondance with the general model proposed by Ravnas and Steel (1998), the basin-filling has two large cycles-rift (sediment-balanced and -overfilied)and postrift (sediment-underfilled and -starved). During the rifting process, the rifted lake developed through three stages: early, climax and late. The sedimentary characteristics of reservoir rocks show that barrier bar, lagoon and tidal channel facies well developed in Zhuhai Formation;offshore, tidal and barrier bar well developed in Zhujiang Formation. Neighborly, Shenhu , Wenchang and Enping formations deposited in rifted lakes during Paleogene time ; Zhujiang Formation deposited in bay, lagoon and shorefnce in late Paleogene. Zhujiang and other formations deposited in offshore and open shallow sea to shelf.

  1. Contemporary condition of macrozoobenthos in ultrashallow zone of Taman Bay, Sea of Azov

    Science.gov (United States)

    Spiridonov, V. A.; Kolyuchkina, G. A.; Belyaev, N. A.; Basin, A. B.; Kozlovsky, V. V.

    2016-03-01

    The distribution of macrozoobenthic communities was studied in a vast ultrashallow (0-1.2 m deep) zone of northwestern Taman Bay (separated from the Kerch Strait by Chushka spit) in 2008-2009. Fifty-two species of benthic invertebrates were recorded. The species number, as well as Shannon and Pielou diversity indices, increased along Chushka spit from base to tip. The usual inhabitants of lagoons and estuaries of the Mediterranean Basin and the open Sea of Azov dominated in benthic communities: mollusks Abra segmentum and Hydrobia acuta and polychaetes Heteromastus filiformis and Hediste diversicolor (the latter only in summer). Changes in the community structure were largely determined by the seasonal dynamics of dominant species populations, which was similar to their dynamics in certainother transitional water bodies of the Mediterranean Basin. These changes indicate normal running of seasonal processes in the macrobenthic communities of Taman Bay in 2008 rather than the consequences of a catastrophic black oil spill in the Kerch Strait in November 2007.

  2. Tidal characteristics of Maputo Bay, Mozambique

    Science.gov (United States)

    Canhanga, Sinibaldo; Dias, João Miguel

    2005-12-01

    The tidal characteristics of Maputo Bay (a bay located in South part of Mozambique) were assessed in this work through the implementation of a numerical model (SIMSYS2D) and exploration of its numerical results, and by the analysis of observed time series of free surface elevations in Maputo Harbor. The calibration of the numerical model was carried out based on time series of tidal currents and free surface elevation, which were collected at Maputo Harbor, Baixo Ribeiro and Portuguese Island. By means of the model results, important harmonic constants of the tidal heights and currents, as well as the form factor, were computed. These results have revealed that there is a phase delay and an increase in amplitude of the major constituents as the tide propagates to the inshore zone. Based on these results, the tidal ellipses in whole Maputo Bay were also computed, which showed the pattern of the tidal currents. The hydrodynamics of the Maputo Bay under extreme tidal conditions were also analyzed (during the largest spring tide and smallest neap tide). The phase difference between tidal heights and currents revealed that there are no maximum fluxes of energy in most of Maputo Bay and that the mean tidal current (residual) may be different from zero in this system.

  3. Basin Hopping Graph

    DEFF Research Database (Denmark)

    Kucharik, Marcel; Hofacker, Ivo; Stadler, Peter;

    2014-01-01

    folding free energy landscape, however, can provide the relevant information. Results We introduce the basin hopping graph (BHG) as a novel coarse-grained model of folding landscapes. Each vertex of the BHG is a local minimum, which represents the corresponding basin in the landscape. Its edges connect...... basins when the direct transitions between them are “energetically favorable”. Edge weights endcode the corresponding saddle heights and thus measure the difficulties of these favorable transitions. BHGs can be approximated accurately and efficiently for RNA molecules well beyond the length range...

  4. Sediment grab data from October 1999 in Apalachicola Bay, Florida

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Apalachicola Bay National Estuarine Research Reserve and the NOAA Office for Coastal Management worked together to map benthic habitats within Apalachicola Bay,...

  5. Benthic grab data from October 1999 in Apalachicola Bay, Florida

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Apalachicola Bay National Estuarine Research Reserve and the NOAA Office for Coastal Management worked together to map benthic habitats within Apalachicola Bay,...

  6. Back Bay: Report on Salinity and Water Clarity in 1986

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Salinity, turbidity and various other water quality parameters were monitored monthly in 1986 at 24 stations on Back Bay. Results show Back Bay to be brackish (mean...

  7. ISOLATION AND DIVERSITY OF ACTINOMYCETES IN THE CHESAPEAKE BAY

    Science.gov (United States)

    Chesapeake Bay was investigated as a source of actinomycetes to creen for production of novel bioactive compounds. he presence of relatively large populations of actinoplanetes, chemotype IID actinomycetes in Chesapeake Bay sediment samples indicates that is an eminently suitable...

  8. Heavy mineral placers off Kalbadevi Bay, Ratnagiri, Maharashtra

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.

    Sedimentological and heavy mineral studies were carried out for two offshore profiles in the Kalbadevi Bay, Ratnagiri, Maharashtra. The surface samples from the Bay were collected during pre- and post- monsoon period (i.e. in May and October...

  9. Algae Reefs in Shark Bay, Western Australia, Australia

    Science.gov (United States)

    1990-01-01

    Numerous algae reefs are seen in Shark Bay, Western Australia, Australia (26.0S, 113.5E) especially in the southern portions of the bay. The south end is more saline because tidal flow in and out of the bay is restricted by sediment deposited at the north and central end of the bay opposite the mouth of the Wooramel River. This extremely arid region produces little sediment runoff so that the waters are very clear, saline and rich in algae.

  10. REE enrichment in Havana Bay surface sediments using INAA

    International Nuclear Information System (INIS)

    Rare earth elements (REE) levels in Havana bay surface sediments are determined by instrumental neutron activation analysis. REE contents follow the order: Ce > La > Nd > Sm > Eu, Yb, Tb, Lu. The results shows that REE content in the bay is site depended and suggest that an REE anthropogenic input into the bay occurred. The chondrite and upper continental crust-normalizations confirm the REE enrichment of the bay sediments, respect to the REE content in sediments from the Cuban northwestern coast. (author)

  11. Numerical Simulation of Tidal Current in a Bay

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    -Based on the multilevel model, numerical calculations of tidal current affected by the M2 tide in the Tokyo Bay have been carried out. The results of calculation are compared with the data observed in the Tokyo Bay and the result calculated by an approximate formula as the Tokyo Bay is regarded as a rectangular bay, and good agreement is found. It is proved that the mathematical model and the calculation method are correct and useable

  12. Assessment of contamination in the Shuttle bay

    Science.gov (United States)

    Jeffery, J. A.; Maag, C. R.; Seastrom, J. W.; Weber, M. F.

    1982-01-01

    The results of an analytical study to determine the contamination potential of the Galileo probe instruments while in the STS bay are presented. The study covered conditions wherein the instruments weren't covered, covers were used with vent paths of varying sizes, and if the instruments were sealed and a nitrogen purge was employed. The contamination limits for each of the Galileo instruments are considered. Analytic approximations are devised for the diffusion of particles from surfaces and materials in the Shuttle bay during the ascent phase, using Fick's second law of diffusion. It is recommended that an instrument purge be implemented during the first 15 min of Shuttle flight in order to carry the contaminants from both the bay fixtures and from the instruments into space. Covers are suggested as necessary for the most sensitive instruments.

  13. Meteorological research studies at Jervis Bay, Australia

    International Nuclear Information System (INIS)

    A climatological study of the winds and temperature from the Jervis Bay region which commenced in October 1970 has shown the presence of a coastal sea breeze and secondary bay breeze circulation system. In an attempt to define the influence of the Murray's Beach site on the local atmospheric dispersion, special smoke plume photography studies were conducted in the lower atmosphere. In June 1972 a meteorological acoustic sounding research programme was initiated at the Jervis Bay settlement. The aims of the research are to calibrate the sounder in terms of surface wind, turbulence and temperature measurements pertinent to a description of the lower atmospheric dispersion potential. Preliminary results on six months' data have shown encouraging correlations between the acoustic sounder patterns and particularly the wind direction turbulence traces. (author)

  14. Endocrine disrupter - estradiol - in Chesapeake Bay tributaries

    Energy Technology Data Exchange (ETDEWEB)

    Dorabawila, Nelum [University of Maryland Eastern Shore, Princess Anne, MD 21853 (United States); Gupta, Gian [University of Maryland Eastern Shore, Princess Anne, MD 21853 (United States)]. E-mail: gcgupta@umes.edu

    2005-04-11

    Exogenous chemicals that interfere with natural hormonal functions are considered endocrine disrupting chemicals (EDCs). Estradiol (17{beta}-estradiol or E2) is the most potent of all xenoestrogens. Induction of vitellogenin (VTG) production in male fish occurs at E2 concentrations as low as 1 ng l{sup -1}. E2 reaches aquatic systems mainly through sewage and animal waste disposal. Surface water samples from ponds, rivers (Wicomico, Manokin and Pocomoke), sewage treatment plants (STPs), and coastal bays (Assawoman, Monie, Chincoteague, and Tangier Sound - Chesapeake Bay) on the Eastern Shore of Maryland were analyzed for E2 using enzyme linked immuno-sorbent assay (ELISA). E2 concentrations in river waters varied between 1.9 and 6.0 ng l{sup -1}. Highest E2 concentrations in river waters were observed immediately downstream of STPs. E2 concentrations in all the coastal bays tested were 2.3-3.2 ng l{sup -1}.

  15. Bayes' theorem: scientific assessment of experience

    Directory of Open Access Journals (Sweden)

    Lex Rutten

    2010-10-01

    Full Text Available Homeopathy is based on experience and this is a scientific procedure if we follow Bayes' theorem. Unfortunately this is not the case at the moment. Symptoms are added to our materia medica based on absolute occurrence, while Bayes theorem tells us that this should be based on relative occurrence. Bayes theorem can be applied on prospective research, but also on retrospective research and consensus based on a large number of cases. Confirmation bias is an important source of false data in experience based systems like homeopathy. Homeopathic doctors should become more aware of this and longer follow-up of cases could remedy this. The existing system of adding symptoms to our materia medica is obsolete.

  16. Dust settles at Dalrymple Bay Terminal

    International Nuclear Information System (INIS)

    With an annual loading capacity approaching 60Mt, Queensland's Dalrymple Bay Coal Terminal is one of the largest and most efficient coal export facilities in Australia. Each day, DBCT handles thousands of tonnes of coal transported directly from the Bowen Basin via an electrified railway and bound, ultimately, for out-loading onto bulk carrier ships. It is little wonder then that dust control and an accurate knowledge of coal moisture content are key priorities for DBCT. In early 2004, these priorities, together with an undertaking to the Co-ordinator General to reduce dust emissions, saw DBCT investigate the CSIRO-developed Low Frequency Microwave (LFM) Moisture Analyser. The LFM Analyser is specifically designed to deliver accurate, online measurements of moisture in continuous on-conveyor applications. At this stage, it was already enjoying significant success in the iron ore market with BHP Billiton Iron Ore investing in multiple units as part of its moisture control strategy for the Marra Mamba ore-types. The LFM Analysers, now being commercialised by spin-out company Intalysis, were commissioned in July 2004. Babcock and Brown Infrastructure (BBI), the company that holds the long-term leasehold of DBCT, was heavily involved in the analyser's commissioning. BBI's electrical supervisor Doug Mitchell says the analyser offers the means for DBCT to meet the environmental conditions of the terminal license while at the same time enabling it to meet its individual contract obligations with the terminal customers. 'This basically involves ensuring the moisture content for each coal type does not exceed that which has been agreed upon with terminal customer,' Mitchell says. DBCT has installed two analysers on the in loading conveyors, each about 100m from the coal discharge hoppers. They are fitted to steel cord belts at a nominal speed of around 6m/sec that carry the coal to either 4250tph or 5500tph yard stacking machines, depending on the string selected for

  17. Early Mesozoic basin aquifers

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set represents the extent of the Early Mesozoic basin aquifers in the states of Massachusettes, Connecticut, New York, New Jersey, Pennsylvania, Maryland,...

  18. Mitigation : Closed Basin Project

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The upcoming meeting on waterfowl mitigation for the Closed Basin Project will have several people talk about possible changes to the waterfowl mitigation program....

  19. Tulare Basin protection plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Tulare Basin Protection Plan has been initiated by The Nature Conservancy to elucidate the problems and opportunities of natural diversity protection....

  20. California Air Basins

    Data.gov (United States)

    California Department of Resources — Air ResourcesCalifornia Air Resources BoardThe following datasets are from the California Air Resources Board: * arb_california_airbasins - California Air BasinsThe...

  1. Migratory birds and marine mammals of the Bristol Bay region: Wildlife narratives for the Bristol Bay Cooperative Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This is a collection of reports on migratory birds and marine mammals of the Bristol Bay region for the purpose of facilitating the planning process in Bristol Bay....

  2. Empirical Bayes analysis of single nucleotide polymorphisms

    Directory of Open Access Journals (Sweden)

    Ickstadt Katja

    2008-03-01

    Full Text Available Abstract Background An important goal of whole-genome studies concerned with single nucleotide polymorphisms (SNPs is the identification of SNPs associated with a covariate of interest such as the case-control status or the type of cancer. Since these studies often comprise the genotypes of hundreds of thousands of SNPs, methods are required that can cope with the corresponding multiple testing problem. For the analysis of gene expression data, approaches such as the empirical Bayes analysis of microarrays have been developed particularly for the detection of genes associated with the response. However, the empirical Bayes analysis of microarrays has only been suggested for binary responses when considering expression values, i.e. continuous predictors. Results In this paper, we propose a modification of this empirical Bayes analysis that can be used to analyze high-dimensional categorical SNP data. This approach along with a generalized version of the original empirical Bayes method are available in the R package siggenes version 1.10.0 and later that can be downloaded from http://www.bioconductor.org. Conclusion As applications to two subsets of the HapMap data show, the empirical Bayes analysis of microarrays cannot only be used to analyze continuous gene expression data, but also be applied to categorical SNP data, where the response is not restricted to be binary. In association studies in which typically several ten to a few hundred SNPs are considered, our approach can furthermore be employed to test interactions of SNPs. Moreover, the posterior probabilities resulting from the empirical Bayes analysis of (prespecified interactions/genotypes can also be used to quantify the importance of these interactions.

  3. 46 CFR 151.03-33 - Lakes, bays, and sounds.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Lakes, bays, and sounds. 151.03-33 Section 151.03-33... CARRYING BULK LIQUID HAZARDOUS MATERIAL CARGOES Definitions § 151.03-33 Lakes, bays, and sounds. A designation for all vessels navigating the waters of any of the lakes, bays, or sounds other than the...

  4. 46 CFR 188.10-39 - Lakes, bays, and sounds.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Lakes, bays, and sounds. 188.10-39 Section 188.10-39... PROVISIONS Definition of Terms Used in This Subchapter § 188.10-39 Lakes, bays, and sounds. Under this designation shall be included all vessels navigating the waters of any of the lakes, bays, or sounds,...

  5. 46 CFR 90.10-19 - Lakes, bays, and sounds.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Lakes, bays, and sounds. 90.10-19 Section 90.10-19... PROVISIONS Definition of Terms Used in This Subchapter § 90.10-19 Lakes, bays, and sounds. Under this designation shall be included all vessels navigating the waters of any of the lakes, bays, or sounds...

  6. Erosion rates during rapid deglaciation in Icy Bay, Alaska

    Science.gov (United States)

    Koppes, MichèLe; Hallet, Bernard

    2006-06-01

    Contemporary glacial erosion rates based on sediment yields in southeast Alaska merit considerable attention because they are unsurpassed worldwide, and they significantly exceed long-term exhumation rates in the region. Two issues are likely to contribute to these high rates: contemporary sediment yields in fjords (1) have generally been overestimated by failing to account for the considerable input of subaerially derived material and (2) are exceptionally high because tidewater glaciers in southeast Alaska have been anomalously dynamic and erosive during the past century of rapid retreat. To investigate these influences and to quantify the rate at which Tyndall Glacier erodes its basin we present seismic data defining the volume of sediments in Taan Fjord, Icy Bay. We subtract the contribution of subaerially derived sediments from the fjord sediment package to determine the sediment yield directly from Tyndall Glacier during the most recent period of retreat: 1962-1999. Using a numerical model of proglacial glacimarine sedimentation, we then calculate the annual sediment yield from, and the corresponding erosion rate of, Tyndall Glacier during this period, which averages 28 ± 5 mma-1. A strong correlation emerges between glacial retreat rates and glacial sediment yields, implying that most contemporary sediment yield data from retreating tidewater glaciers may correspond to contemporary erosion rates that are a factor of 3.5 ± 1.5 higher than in the long term. Hence we estimate the long-term erosion rate for Tyndall Glacier to be 9 ± 2 mma-1.

  7. K Basin Hazard Analysis

    International Nuclear Information System (INIS)

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Final Safety Analysis Report. This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report

  8. K Basins Hazard Analysis

    International Nuclear Information System (INIS)

    This report describes the methodology used in conducting the K Basins Hazard Analysis, which provides the foundation for the K Basins Safety Analysis Report (HNF-SD-WM-SAR-062/Rev.4). This hazard analysis was performed in accordance with guidance provided by DOE-STD-3009-94, Preparation Guide for U. S. Department of Energy Nonreactor Nuclear Facility Safety Analysis Reports and implements the requirements of DOE Order 5480.23, Nuclear Safety Analysis Report

  9. The Ebro river basin

    OpenAIRE

    Darbra Roman, Rosa Maria

    2011-01-01

    River basins worldwide are under pressure from economic activities. In Europe, the two main factors hindering the achievement of good chemical and ecological status of European river basins are pollution, mainly coming from agriculture, and hydromorphology (e.g. for navigation, hydroelectricity and flood control). The economic activities affect the chemical and ecological status of rivers, lakes and groundwater and deplete available soil, sediments and water resources. The w...

  10. Mesozooplankton production, grazing and respiration in the Bay of Bengal: Implications for net heterotrophy

    Science.gov (United States)

    Fernandes, Veronica; Ramaiah, N.

    2016-03-01

    Mesozooplankton samples were collected from the mixed layer along a central (along 88°E) and a western transect in the Bay of Bengal during four seasons covered between 2001 and 2006 in order to investigate spatio-temporal variability in their biomass. At these stations, grazing and respiration rates were measured from live zooplankton hauled in from the surface during December 2005. Akin to the mesozooplankton "paradox" in the central and eastern Arabian Sea, biomass in the mixed layer was more or less invariant in the central and western Bay of Bengal, even as the chl a showed marginal temporal variation. By empirical equation, the mesozooplankton production rate calculated to be 70-246 mg C m- 2 d- 1 is on par with the Arabian Sea. Contrary to the conventional belief, mesozooplankton grazing impact was up to 83% on primary production (PP). Low PP coupled with very high zooplankton production (70% of PP) along with abundant bacterial production (50% of the PP; Ramaiah et al., 2009) is likely to render the Bay of Bengal net heterotrophic, especially during the spring intermonsoon. Greater estimates of fecal pellet-carbon egestion by mesozooplankton compared to the average particulate organic carbon flux in sediment traps, implies that much of the matter is recycled by heterotrophic communities in the mixed layer facilitating nutrient regeneration for phytoplankton growth. We also calculated that over a third of the primary production is channelized for basin-wide zooplankton respiration that accounts for ~ 52 Mt C annually. In the current scenario of global warming, if low (primary) productive warm pools like the Bay of Bengal continue to be net heterotrophic, negative implications like enhanced emission of CO2 to the atmosphere, increased particulate flux to the deeper waters and greater utilization of dissolved oxygen resulting in expansion of the existing oxygen minimum zone are imminent.

  11. Abundance of Atlantic walrus in Western Nares Strait, Baffin Bay Stock, during summer

    Directory of Open Access Journals (Sweden)

    Robert EA Stewart

    2013-09-01

    Full Text Available Atlantic walruses (Odobenus rosmarus rosmarus belonging to the Baffin Bay subpopulation occur year round in the North Water polynya (NOW between NW Greenland and eastern Ellesmere Island (Canada. They are hunted for subsistence purposes by residents of the Qaanaaq area (NW Greenland bordering the NOW to the east and by Canadian Inuit at the entrance to Jones Sound in Nunavut. During the open-water period NW Greenland is virtually devoid of walruses which concentrate along eastern and southern Ellesmere Island at this time of the year. To determine the abundance of walruses in the NOW area, aerial surveys were conducted in August of 1999, 2008, and 2009. In July 2009, nine satellite-linked transmitters were deployed in nearby Kane Basin. Surveys on 9 and 20 August 2009 along eastern Ellesmere Island were the most extensive and were augmented with concomitant data on haul-out and at water surface activity from three (1 F, 2 M of the nine tags that were still functioning. We therefore focus on the 2009 surveys. Walruses were observed on the ice and in water primarily in Buchanan Bay and Princess Marie Bay where the remaining functional tags were located. The Minimum Counted population (MCP was 571 on 20 August. Adjusting the MCP of walruses on ice for those not hauled out, the estimate of abundance of walruses in the Baffin Bay stock was 1,251(CV=1.00, 95% CI = 1,226 when adjusted by the proportion of tags ‘dry’ at the time of the survey and 1,249 (CV=1.12, 95% CI = 1,370 when adjusted by the average time tags were dry. The surveys did not cover all potential walrus summering habitat along eastern Ellesmere Island and are negatively biased to an unknown degree.

  12. Exploration of PPP financing model for the cross-sea channel of the Bohai Strait%渤海海峡跨海通道建设的PPP融资模式探索研究

    Institute of Scientific and Technical Information of China (English)

    张凌; 王磊

    2013-01-01

    兴建渤海海峡跨海通道是一项利国利民的重大工程项目。实现投资渠道多元化,特别是吸引国内外民营资本是解决渤海海峡跨海通道建设资金的重要途径。Public-private-partnership(PPP)融资模式克服了build-operate-transfer(BOT)模式中两个最关键的缺点,即项目前期工作的周期过长以及投资方和贷款人风险过大。PPP融资模式比BOT模式更优越,效率更高,风险分配更合理,项目融资的成功可能性也更大,而且在PPP模式下,政府部门拥有一定决策权和控制权。渤海海峡跨海通道可以借鉴PPP融资模式。%The construction of the cross-sea channel of the Bohai Strait is a great project which is benefiti-cial to our country and people. Diversification of investment channels,especially to attract domestic and foreign private capital,is an important way to raise funds for the cross-sea channel of the Bohai Strait. The two most crit-ical shortcomings of build-operate-transfer(BOT)modle are overcomed by means of public-private-partnership (PPP)model. They are too long preparatory work for the project and great risks of investors and lenders. PPP model is superior to the BOT model,more efficient than BOT,and is more rational for allocation of risks. Fi-nancing success of PPP model for the project is greater. Moreover,government can grasp decision-making power and control power of the project in the PPP model. PPP model can be learned in the cross-sea channel of the Bohai Strait.

  13. Utilization of reactor bays of decommissioned submarines

    International Nuclear Information System (INIS)

    Radiation concerns regarding dismantling and storage of decommissioned reactors and reactor bays from nuclear submarines are briefly summarized. Calculation results are presented for gamma dose rates, contamination density, and the expected location of maximum exposure dose rate on the submarine hull. However, it is noted that radiation measurements must be obtained for each ship due to differences in operating conditions. Long-term storage options for containerized reactors and reactor bays are very briefly outlined; these include placing them in concrete-lined trenches shielded from the atmosphere or in underground tunnels shielded from water. 5 refs., 1 fig., 1 tab

  14. Roebuck Bay Invertebrate and bird Mapping 2006

    OpenAIRE

    Piersma, Theunis; Pearson, Grant B.; Hickey, Robert; Dittmann, Sabine; Rogers, Danny I.; Folmer, Eelke; Honkoop, Pieter; Drent, Jan; de Goeij, Petra; Marsh, Loisette

    2006-01-01

    1. This is a report on a survey of the benthic ecology of the intertidal flats along the northern shores of Roebuck Bay in June 2006. In the period 11-20 June we mapped both the invertebrate macrobenthic animals (those retained by a 1 mm sieve) over the whole of the northern intertidal area of Roebuck Bay and the shorebirds that depend on this food resource. The northern mudflats previously had been benthically mapped in 1997, 2000 and 2002. In addition to the mapping efforts, as a reach-out ...

  15. Bayes estimation of the multiple correlation coefficient

    OpenAIRE

    Tiwari, RC

    1989-01-01

    Let R denote the population multiple correlation coefficient of one variable on the other (m-1), in a m-variate normal —2 distribution. Bayes estimator of R, given only the sample 2 multiple correlation coefficient R, is derived with respect to the squared error loss function and a Beta prior distribution.-2 These results are then related to the Bayes estimates of R /(1-_o R), a parameter considered recently by Muirhead (1985). The ideas are illustrated and the effect of various parameters st...

  16. Characteristics of radionuclide distribution in surface layer sediments of Osaka Bay and Lake Biwa

    International Nuclear Information System (INIS)

    The PCDDs/DFs contamination in the environment has concerned our society even after prohibition of its use. Dr. Sakai et al. showed the change in concentration of PCDDs/DFs historically in sediment core samples taken from Osaka Bay and Lake Biwa. Sediment core samples were taken from five points on urban coastal area in Osaka Bay and three points on the coastal area in Lake Biwa. We measured the concentration of 226Ra, 210Pb, 228Th, 40K and 137Cs in the sediment core samples by using gamma-ray spectrometry and estimated the sedimentation rate with the 210Pb method. The sedimentation rate was about (200-600) mg/cm2·y in Osaka Bay and (150-300) mg/cm2·y n Lake Biwa. The characteristics on distribution of the 226Ra, 210Pb, 228Th, 40K and 137Cs concentration in the surface sediments on the cost of Osaka Bay and Lake Biwa were also investigated. The peaks of 137Cs concentration (35-70 Bq/kg) in three core samples from Lake Biwa were clearly observed. The sedimentation rates with 137Cs distribution indicated similarity to those calculated from the 210Pb method in the samples of Lake Biwa. However, a remarkable peak of 137Cs concentration was not observed in the core samples taken in Osaka Bay. These concentration were under 6 Bq/kg. We have kept on measuring the annual deposition rate (about 100 Bq/m2) of 210Pb in the Institute in Osaka with observation of the monthly deposition using a basin. We estimated the area contributed to the points taken core samples in comparison the annual deposition rate of 210Pb at the sampling points in Osaka Bay and Lake Biwa with that mentioned above. The mineral composition of the core samples were also measured by X-ray diffraction analysis. It is possible that the distribution of the concentration of these nuclides and the mineral composition in the sediments shows the environmental change. (author)

  17. Abnormality of Development in Strongylocentrotus intermedius (A. Agassiz) Larvae from Polluted Habitat in Amursky Bay, Peter the Great Bay

    OpenAIRE

    Naidenko, Tamara

    1997-01-01

    Amursky Bay, Peter the Great Bay, Sea of Japan is very much prone to anthropogenic pollution by heavy metals, oils, phenols, pesticides, etc. To clarify the effect of pollution, tests of the embryonic and larval development of sea urchin Strongylocentrotus intermedius are conducted using material collected from polluted habitats in Amursky Bay. A population from an unpolluted site in Vityaz Bay is used as a control. Various abnormal patterns of development including failure to metamorphose ar...

  18. An 800-year record of terrestrial organic matter from the East China Sea shelf break: Links to climate change and human activity in the Changjiang Basin

    Science.gov (United States)

    Li, Zhong Qiao; Wu, Ying; Liu, Su Mei; Du, Jin Zhou; Zhang, Jing

    2016-02-01

    The East China Sea (ECS) is a large river dominated marginal sea and receives massive volumes of terrestrial material from the Changjiang (Yangtze River). As the ECS preserves a record of terrestrial material derived from the Changjiang Basin, cores collected from this region can be used to reconstruct paleoclimate change and human disturbance in the watershed. A core (P4) was collected from the ECS shelf break and analyzed for bulk parameters (organic carbon (OC), total nitrogen (TN), and stable carbon isotopes (δ13C)), lignin phenols, and 3,5-dihydroxy benzoic acid (DHBA). The depth profiles of these parameters indicate stable and consistent marine production. The lignin source indices, cinnamyl phenols vs. vanillyl phenols (C/V) and syringyl phenols vs. vanillyl phenols (S/V), were in agreement with previously reported results from ECS surface sediments, but differed markedly from Bohai Sea surface sediments. The ratio of acid to aldehyde in vanillyl phenols ((Ad/Al)v) indicated the terrestrial OC in this core was refractory. At the same time, the variation in lignin phenols is positively correlated with the strength of the Indian Summer Monsoon (ISM) over the last 800 years (phuman activity in the upper Changjiang Basin over this period.

  19. Estimation of submarine groundwater discharge to Osaka Bay, Japan by numerical simulation

    Science.gov (United States)

    Yasumoto, J.; Nakaya, S.; Mitamura, M.; Takahashi, M.; Onodera, S.; Taniguchi, M.

    2009-12-01

    Urbanization induces a rapid direct runoff and less rainwater recharge to shallow groundwater. In order to manage water resource in a basin scale, it is important to estimate local hydrological cycle depending on land use. Therefore, understanding the water flow, such as direct runoff and groundwater discharge is essential since these are important hydrological components of water resource management (Carl. E. R et al., 2003). Besides, coastal environment deterioration caused by nutrient discharge from the land area is a serious problem. Previous research made in the last decades has shown that direct groundwater discharge to coastal zone is a significant pathway of water and nutrient form land to ocean (Moore, 1996). For instance, groundwater discharge has often contained higher chronic inputs, which is from fertilizers and sewage. Therefore, groundwater discharge often makes the significant effect to coastal marine eutrophication (Taniguchi, 2002). This study focuses on the environmental rehabilitation of Osaka Bay, Japan, where eutrophication has been occurred recently. It is recognized that this problem is caused by an increase of the nutrient input, as fertilizers and wastewater, through direct runoff and groundwater discharge from the residential, industrial and agricultural areas in Osaka Bay catchment. However, groundwater discharge has not yet been quantified as the pathway of nutrients input in this area. In a present study, a simple but efficient approach is proposed in order to estimate groundwater discharge from the basin by water budget analysis. The groundwater recharge model was applied to calculate hydrological components, such as direct runoff, groundwater recharge and evapotranspiration in the basin. Water balance analysis is effective method to estimate the groundwater discharge from a river basin to sea. However, it is often difficult to estimate the exact SGD flux with water budget analysis in a large area. Therefore, it is necessary to

  20. Corrosion Failure of Bypass Pipe of Well F in Bohai Oilfield%渤海某油田F井旁路管腐蚀失效研究

    Institute of Scientific and Technical Information of China (English)

    王晓鹏; 王啸; 修海媚; 谭才渊; 杨进; 殷启帅

    2016-01-01

    ABSTRACT:Objective The phenomenon of bypass pipe corrosion failure occurs in Bohai Oilfield. Taking Well F in Bohai Oilfield as an example, this paper investigated the corrosion mechanism of bypass pipe to guide the selection of bypass pipe materi-al, and to determine the anticorrosive direction and measures of this oil field.MethodsBased on the preliminary analysis of pipe corrosion, using scanning electron microscope, tensile strength test machine, X ray diffraction instrument and so on, physical and chemical performance analysis, metallographic analysis, corrosion product XRD analysis and corrosion product spectrum analysis were carried out on corroded bypass pipe of well F.Results In the aspect of chemical composition, the original chemical compo-sition of the 1#, 2#, 3#bypass pipes met the requirements of Spec 5CT API. In the aspect of mechanical properties, the tensile strength and yield strength of 1# bypass pipe were slightly lower than the standard requirements, and the mechanical properties of the 2#, 3#bypass pipes met the requirements of Spec 5CT API. In the aspect of corrosion products, the corrosion products of the 1#, 2#, 3# bypass pipes were mainly composed of C, O, S, Fe, Ca and Mn. Iron oxide was the main product, followed by sulfide, in which C, Ca, O elements should be derived from environmental media, and a small amount of Ti element might be derived from the surrounding contact metal. In the aspect of compounds produced by corrosion, 1# bypass pipe mainly produced iron oxide, and it contained Ca2Fe2O5 which was inferred to be derived from the formation of sand or ore. 2#bypass pipe mainly produced typical rust components, mainly iron oxide, and a small amount of FeO(OH), which was unstable, and could easily produce iron oxide in the air. Conclusion The corrosion of well F was erosion-corrosion and galvanic corrosion.%目的:旁路管腐蚀现象在渤海油田时有发生,以渤海某油田F井为例,研究该油田旁路管腐蚀机理

  1. Contaminants in redhead ducks wintering in Baffin Bay and Redfish Bay, Texas

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A sample of 39 redhead ducks was collected from Redfish and Baffin Bays on the Texas Coast during the winter of 1988-1989 to obtain baseline information on...

  2. South Bay Salt Pond initial stewardship plan & related Bay Area restoration projects

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Initial Stewardship Plan for the South Bay Salt Pond Restoration Project outlines a process to reduce the salinity of the existing salt ponds and to manage the...

  3. Geology and geomorphology--Drakes Bay and Vicinity Bay Map Area, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the geologic and geomorphic map of the Drakes Bay and Vicinity map area, California. The polygon shapefile is included in...

  4. Red Tides in Nagasaki Bay during Summer Season of 1979

    OpenAIRE

    Dahril, Tengku; Iizuka, Shoji

    1981-01-01

    Almost every year during the summer season, red tides have occurred in Nagasaki Bay. Red tides are caused by various kind of phytoplankton and bay waters discolor like coffee by the exclusive growth of a single organism or mixed growth of two or three organisms. However, very little is known about red tide in this bay. In this paper the authors dealt with red tides in Nagasaki Bay during the summer season of 1979. The innermost part of this bay was divided into 3 areas. Five water sampling st...

  5. The land-sourced pollution in the Jiaozhou Bay

    Institute of Scientific and Technical Information of China (English)

    GAO Zhenhui; YANG Dongfang; QIN Jie; XIANG Lihong; ZHANG Ke

    2008-01-01

    In recent years,natural environment of the Jiaozhou Bay has been changed largely by fast developing industry and agriculture of the cities around,from which wastewaters were generated.The size of the bay has been continuously shrunk with reduced river flows,resulting in serious contamination to the marine lives in the bay.After analyzing the basic historical data,the authors put forward a suggestion of how to protect the bay ecology for sustaining the resources in the Jiaozhou Bay.

  6. 渤海浮游动物群落生态特点Ⅲ.部分浮游动物数量分布和季节变动%The characteristics of zooplankton community in the Bohai Sea Ⅲ. The distribution of abundance and seasonal dynamics of major taxa except copepoda

    Institute of Scientific and Technical Information of China (English)

    毕洪生; 孙松; 高尚武; 张光涛; 张芳

    2001-01-01

    Samples from twelve consecutive cruises in 1959 were analyzed to determine the distribution patterns of abundance and seasonal dynamics of major taxa in the Bohai Sea except copepoda.   1) Coelenterata: The seasonal changes of medusae showed bimodal with the first peak in February and the second in June. The common species included Rathkea octopunctata, Phialidium chengshanense, P. discoidum, Eirene ceylonensis, Liriope tetraphylla, Proboscidactyla flavicirrata, Muggiaea atlantica. Most of them were neritic species and they mainly distributed in the coastal areas. Rathkea octopunctata peaked in February and Eirene ceylonensis, Phialidium chengshanense, P. discoidum, Eirene ceylonensis peaked in summer.   2) Cladocera: The most common species was Penilia avirostris. Penilia avirostris was a typical neritic species and mainly distributed in coastal waters in Laizhou Bay. It peaked in June with an average density of 151.1 ind./m3 and the highest abundance is 7855 ind./m3.   3) Mysidacea: Gastrosaccus pelagicus, Acanthomysis longirostris, Acanthomysis hwanhaiensis were common species. Gastrosaccus pelagicus was abundant in late autumn and Acanthomysis longirostris correlated little with temperature with three peaks in spring, summer and autumn respectively. These two species were both neritic species and distributed in coastal waters.   4) Appendicularia: Oikopleura longicauda was the most abundant species and its seasonal dynamics showed bimodal with the first peak in May and the second in August. In most of the year, it mainly distributed in coastal waters.   5) Chaetognatha: Sagitta crassa was one of the most important carnivorous species and it was abundant in September. One of the reproductive seasons occurred in June and the other occurred in late autumn.   6) Amphipoda: Themisto gracilipes was one of the most common species in the Bohai Sea. It was most abundant in June and July. Its distribution closely associated with salinity and it

  7. Diurnal variation of oxygen and carbonate system parameters in Tampa Bay and Florida Bay

    Science.gov (United States)

    Yates, K.K.; Dufore, C.; Smiley, N.; Jackson, C.; Halley, R.B.

    2007-01-01

    Oxygen and carbonate system parameters were measured, in situ, over diurnal cycles in Tampa Bay and Florida Bay, Florida. All system parameters showed distinct diurnal trends in Tampa Bay with an average range of diurnal variation of 39.1 μmol kg− 1 for total alkalinity, 165.1 μmol kg− 1 for total CO2, 0.22 for pH, 0.093 mmol L− 1 for dissolved oxygen, and 218.1 μatm for pCO2. Average range of diurnal variation for system parameters in Tampa Bay was 73% to 93% of the seasonal range of variability for dissolved oxygen and pH. All system parameters measured in Florida Bay showed distinct variation over diurnal time-scales. However, clear diurnal trends were less evident. The average range of diurnal variability in Florida Bay was 62.8 μmol kg− 1 for total alkalinity, 130.4 μmol kg− 1 for total CO2, 0.13 for pH, 0.053 mmol L− 1 for dissolved oxygen, and 139.8 μatm for pCO2. The average range of diurnal variation was 14% to 102% of the seasonal ranges for these parameters. Diurnal variability in system parameters was most influenced by primary productivity and respiration of benthic communities in Tampa Bay, and by precipitation and dissolution of calcium carbonate in Florida Bay. Our data indicate that use of seasonal data sets without careful consideration of diurnal variability may impart significant error in calculations of annual carbon and oxygen budgets. These observations reinforce the need for higher temporal resolution measurements of oxygen and carbon system parameters in coastal ecosystems.

  8. Carolina bays of the Savannah River Plant

    Energy Technology Data Exchange (ETDEWEB)

    Schalles, J.F. (Creighton Univ., Omaha, NE (USA)); Sharitz, R.R.; Gibbons, J.W.; Leversee, G.J.; Knox, J.N. (Savannah River Ecology Lab., Aiken, SC (USA))

    1989-01-01

    Much of the research to date on the Carolina bays of the Savannah River Plant and elsewhere has focused on certain species or on environmental features. Different levels of detail exist for different groups of organisms and reflect the diverse interests of previous investigators. This report summarizes aspects of research to date and presents data from numerous studies. 70 refs., 14 figs., 12 tabs.

  9. Bathymetry (2011) for Coral Bay, St. John

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution depth surface for Coral Bay, St. John in the U.S. Virgin Islands (USVI). The...

  10. Bathymetry (2011) for Fish Bay, St. John

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a LiDAR (Light Detection & Ranging) 0.3x0.3 meter resolution depth surface for Fish Bay, St. John in the U.S. Virgin Islands (USVI). The...

  11. Empirical Bayes Estimation in Regression Model

    Institute of Scientific and Technical Information of China (English)

    Li-chun Wang

    2005-01-01

    This paper considers the empirical Bayes (EB) estimation problem for the parameterβ of the linear regression model y = Xβ + ε with ε~ N(0, σ2I) givenβ. Based on Pitman closeness (PC) criterion and mean square error matrix (MSEM) criterion, we prove the superiority of the EB estimator over the ordinary least square estimator (OLSE).

  12. ULF fluctuations at Terra Nova Bay (Antarctica

    Directory of Open Access Journals (Sweden)

    A. Meloni

    2000-06-01

    Full Text Available ULF geomagnetic field measurements in Antarctica are a very important tool for better understanding the dynamics of the Earth’s magnetosphere and its response to the variable solar wind conditions. We review the results obtained in the last few years at the Italian observatory at Terra Nova Bay

  13. Summary report on Bristol Bay murre mortality

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — At least 86,000 common murres died in Bristol Bay, Alaska during a brief period in late April of this year. Evidence suggests that it was a catastrophic event of...

  14. Chesapeake Bay Watershed - Protecting the Chesapeake Bay and its rivers through science, restoration, and partnership

    Science.gov (United States)

    U.S. Geological Survey

    2012-01-01

    The Chesapeake Bay, the Nation's largest estuary, has been degraded due to the impact of human-population increase, which has doubled since 1950, resulting in degraded water quality, loss of habitat, and declines in populations of biological communities. Since the mid-1980s, the Chesapeake Bay Program (CBP), a multi-agency partnership which includes the Department of Interior (DOI), has worked to restore the Bay ecosystem. The U.S. Geological Survey (USGS) has the critical role of providing unbiased scientific information that is utilized to document and understand ecosystem change to help assess the effectiveness of restoration strategies in the Bay and its watershed. The USGS revised its Chesapeake Bay science plan for 2006-2011 to address the collective needs of the CBP, DOI, and USGS with a mission to provide integrated science for improved understanding and management of the Bay ecosystem. The USGS science themes for this mission are: Causes and consequences of land-use change; Impact of climate change and associated hazards; Factors affecting water quality and quantity; Ability of habitat to support fish and bird populations; and Synthesis and forecasting to improve ecosystem assessment, conservation, and restoration.

  15. Responses of upland herpetofauna to the restoration of Carolina Bays and thinning of forested Bay Margins.

    Energy Technology Data Exchange (ETDEWEB)

    Ledvina, Joseph A.

    2008-05-01

    Research on the effects of wetland restoration on reptiles and amphibians is becoming more common, but almost all of these studies have observed the colonization of recently disturbed habitats that were completely dry at the time of restoration. In a similar manner, investigations herpetofaunal responses to forest management have focused on clearcuts, and less intensive stand manipulations are not as well studied. To evaluate community and population responses of reptiles and amphibians to hydrology restoration and canopy removal in the interior of previously degraded Carolina bays, I monitored herpetofauna in the uplands adjacent to six historically degraded Carolina bays at the Savannah River Site (SRS) in South Carolina for four years after restoration. To evaluate the effects of forest thinning on upland herpetofauna, forests were thinned in the margins of three of these bays. I used repeated measures ANOVA to compare species richness and diversity and the abundance of selected species and guilds between these bays and with those at three reference bays that were not historically drained and three control bays that remained degraded. I also used Non-metric Multidimensional Scaling (NMDS) to look for community-level patterns based treatments.

  16. Microbial biogeography of San Francisco Bay sediments

    Science.gov (United States)

    Lee, J. A.; Francis, C. A.

    2014-12-01

    The largest estuary on the west coast of North America, San Francisco Bay is an ecosystem of enormous biodiversity, and also enormous human impact. The benthos has experienced dredging, occupation by invasive species, and over a century of sediment input as a result of hydraulic mining. Although the Bay's great cultural and ecological importance has inspired numerous surveys of the benthic macrofauna, to date there has been almost no investigation of the microbial communities on the Bay floor. An understanding of those microbial communities would contribute significantly to our understanding of both the biogeochemical processes (which are driven by the microbiota) and the physical processes (which contribute to microbial distributions) in the Bay. Here, we present the first broad survey of bacterial and archaeal taxa in the sediments of the San Francisco Bay. We conducted 16S rRNA community sequencing of bacteria and archaea in sediment samples taken bimonthly for one year, from five sites spanning the salinity gradient between Suisun and Central Bay, in order to capture the effect of both spatial and temporal environmental variation on microbial diversity. From the same samples we also conducted deep sequencing of a nitrogen-cycling functional gene, nirS, allowing an assessment of evolutionary diversity at a much finer taxonomic scale within an important and widespread functional group of bacteria. We paired these sequencing projects with extensive geochemical metadata as well as information about macrofaunal distribution. Our data reveal a diversity of distinct biogeographical patterns among different taxa: clades ubiquitous across sites; clades that respond to measurable environmental drivers; and clades that show geographical site-specificity. These community datasets allow us to test the hypothesis that salinity is a major driver of both overall microbial community structure and community structure of the denitrifying bacteria specifically; and to assess

  17. 波浪对泥沙作用的数值研究及在渤海区域的检验%A numerical study of the wave effect on sediment transport and test in the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    滕涌; 杨永增; 芦静; 崔廷伟

    2012-01-01

    针对渤海海域开展了波致底切应力对泥沙作用的数值估计.针对浅水条件,通过理想试验估算了波致底切应力对波流耦合底切应力的贡献.针对渤海大风过程,利用ECOMSED模式,通过波流耦合底边界层模型模拟了渤海区域的泥沙浓度,并利用遥感资料对表层泥沙浓度的数值模拟进行了检验.对比结果表明,考虑波浪作用的情况下,模拟结果在总体分布上得到明显的改善.在大风过程中波浪对0~20 m近岸区域的泥沙再悬浮起主导作用.%The wave effect on sediment transport is analyzed in the Bohai Sea area. First, a series of ideal experiments were carried out to investigate the characteristics of wave-current coupled bottom shear stress and the proportion of wave-induced bottom shear stress. Second, a numerical simulation of suspended sediment concentration was compared with the remote sensing data during a gale process in the Bohai Sea. The results indicate that the model output is improved much when the wave-induced bottom shear stress is considered. The wave plays a key role in the resuspension of sediment in the shallow water of 0 - 20 m depth during the gale weather.

  18. 渤海海冰淡化利用研究进展与问题%Research progress and problems in desalination and utilization of sea ice in Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    李澜涛; 刘成玉; 顾卫; 许映军; 陶军

    2012-01-01

    Sea ice is the frozen product of sea water under low temperature. Frozen period of Bohai Sea prolongs for about 4 months in every winter. Therefore, a wide range of sea ice is formed. Sea ice is dangerous. It often endangers marine transportation and marine industry. While sea ice has resource attribute because of its low salinity, it can be converted to freshwater with low cost. Chinese scholars have carried out the research on Bohai sea ice desalination and utilization since 1995, and have made much progress in resource characteristics, resource extent estimation, desalination technology and melt water agricultural utilization of sea ice with vigorous support from related nation projects. The paper is the review of those research progress and the problems that still need to be solved.%海冰是低温条件下的海水冻结物,在我国渤海,每年冬季有4个月左右的结冰期,形成大范围的海冰.海冰具有灾害性,常对冬季海上运输及海洋生产构成危害,但因其含盐量较低,海冰还具有资源性,有可能以较低成本转化为淡水.自1995年以来,我国学者开展了渤海海冰淡化利用研究,在国家有关项目的大力支持下,已在海冰资源特性、资源量估算、海冰淡化技术和海冰水农业利用等方面均取得了一系列重要的研究进展.本文是对这些研究进展及尚需解决问题的综述.

  19. Biological baseline data Youngs Bay, Oregon, 1974

    Energy Technology Data Exchange (ETDEWEB)

    McMechan, K.J. (ed.); Higley, D.L.; Holton, R.L.

    1975-04-01

    This report presents biological baseline information gathered during the research project, Physical, Chemical and Biological Studies on Youngs Bay.'' Youngs Bay is a shallow embayment located on the south shore of the Columbia River, near Astoria, Oregon. Research on Youngs Bay was motivated by the proposed construction by Alumax Pacific Aluminum Corporation of an aluminum reduction plant at Warrenton, Oregon. The research was designed to provide biological baseline information on Youngs Bay in anticipation of potential harmful effects from plant effluents. The information collected concerns the kinds of animals found in the Youngs Bay area, and their distribution and seasonal patterns of abundance. In addition, information was collected on the feeding habits of selected fish species, and on the life history and behavioral characteristics of the most abundant benthic amphipod, Corophium salmonis. Sampling was conducted at approximately three-week intervals, using commonly accepted methods of animal collection. Relatively few stations were sampled for fish, because of the need to standardize conditions of capture. Data on fish capture are reported in terms of catch-per-unit effort by a particular sampling gear at a specific station. Methods used in sampling invertebrates were generally more quantitative, and allowed sampling at a greater variety of places, as well as a valid basis for the computation of densities. Checklists of invertebrate species and fish species were developed from these samples, and are referred to throughout the report. The invertebrate checklist is more specific taxonomically than are tables reporting invertebrate densities. This is because the methods employed in identification were more precise than those used in counts. 9 refs., 27 figs., 25 tabs.

  20. 捕捞和环境变化对渤海生态系统的影响%Effects of fishing and environmental change on the ecosystem of the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    林群; 王俊; 袁伟; 范振华; 金显仕

    2016-01-01

    以1982年的渤海Ecopath静态模型为起始状态,设置17个功能群,利用CPUE和渔业相对捕捞强度作为时间强制序列,构建渤海Ecosim模型,模拟1982—2008年渤海生态系统发育的动态变化及捕捞的影响;利用气候环境时间序列数据,分析环境变化对渤海生态系统渔业资源的影响。研究发现,1982—2008年间,只有口虾蛄的生物量保持上升趋势,鳀主要经济鱼种小黄鱼、蓝点马鲛、、花鲈、黄鲫等的生物量均呈下降趋势,虾蟹类、头足类的生物量相对稳定。渤海渔获物的平均营养级在1982—2008年间明显下降,总捕捞产量在1984年之后一直保持上升趋势,两者之间存在显著的负相关; FIB指数的变动与捕捞产量的变动保持一致。Q-90多样性指数在1982—1987年间处于波动状态,从1988—1994年间保持增长趋势,在1994年之后迅速下降,由2.5降至0.5附近,渔业生物多样性下降;渤海海表盐度、海表水温、黄河径流量对捕捞产量影响显著。Ecosim 模型终止状态(2008年)与起始状态(1982年)的比较表明,系统成熟度降低,生态系统出现一定程度的退化,渔业捕捞是渔业生态系统出现退化的主要原因,降低了生态系统总体的生物量水平;除捕捞因素外,环境变化也是影响渤海生态系统渔业资源变动的主要因素。%Using a 1982 model of the Bohai Sea as the starting state, an Ecosim model was constructed for the Bohai Sea, including the 17 functional groups. Using time series of catch per unit effort (CPUE) and relative fish-ing effort as the driving factors, this model simulated the dynamic changes in different developmental stages of the Bohai Sea ecosystem and the impact of fishing on this ecosystem. The effects of climate change on the fishery resources of the Bohai Sea ecosystem were analyzed based on the environmental time series data. From 1982 to 2008, the biomass ofOratosquilla oratoria showed an