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Sample records for prudhoe bay oilfield

  1. Characterization of ice nucleating particles during continuous springtime measurements in Prudhoe Bay: an Arctic oilfield location

    Science.gov (United States)

    Creamean, J.; Spada, N. J.; Kirpes, R.; Pratt, K.

    2017-12-01

    Aerosols that serve as ice nucleating particles (INPs) have the potential to modulate cloud microphysical properties. INPs can thus subsequently impact cloud radiative forcing in addition to modification of precipitation formation processes. In regions such as the Arctic, aerosol-cloud interactions are severely understudied yet have significant implications for surface radiation reaching the sea ice and snow surfaces. Further, uncertainties in model representations of heterogeneous ice nucleation are a significant hindrance to simulating Arctic mixed-phase cloud processes. Characterizing a combination of aerosol chemical, physical, and ice nucleating properties is pertinent to evaluating of the role of aerosols in altering Arctic cloud microphysics. We present preliminary results from an aerosol sampling campaign called INPOP (Ice Nucleating Particles at Oliktok Point), which took place at a U.S. Department of Energy's Atmospheric Radiation Measurement (DOE ARM) facility on the North Slope of Alaska. Three time- and size-resolved aerosol samplers were deployed from 1 Mar to 31 May 2017 and were co-located with routine measurements of aerosol number, size, chemical, and radiative property measurements conducted by DOE ARM at their Aerosol Observing System (AOS). Offline analysis of samples collected at a daily time resolution included composition and morphology via single-particle analysis and drop freezing measurements for INP concentrations, while analysis of 12-hourly samples included mass, optical, and elemental composition. We deliberate the possible influences on the aerosol and INP population from the Prudhoe Bay oilfield resource extraction and daily operations in addition to what may be local background or long-range transported aerosol. To our knowledge our results represent some of the first INP characterization measurements in an Arctic oilfield location and can be used as a benchmark for future INP characterization studies in Arctic locations impacted

  2. With Prudhoe Bay in decline

    International Nuclear Information System (INIS)

    Davis, J.M.; Pollock, J.R.

    1992-01-01

    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

  3. Alliancing process helps BP control Prudhoe Bay costs

    International Nuclear Information System (INIS)

    Darley, J.R.

    1992-01-01

    Production and revenues from America's largest oil field are declining. The cost of operating it is rising. If both trends were to continue unchecked, oil production at Prudhoe Bay on Alaska's North Slope could become uneconomic in the next decade. Simply maintaining operating expenditures at current levels - barring a dramatic, lasting increase in oil prices - would postpone the day of reckoning by only a few years. Despite ongoing investments in tempering the decline - gas and water handling expansions, development drilling, enhanced oil recovery, and well maintenance and repair programs - production will continue to decline. That's why it's imperative we reverse the tide of rising costs. This paper reports that to continue to produce oil at Prudhoe well into the 21st century, we must immediately - and continually - cut costs to reflect declining production and revenues

  4. Improved reservoir characterization from waterflood tracer movement, Northwest Fault Block, Prudhoe Bay, Alaska

    International Nuclear Information System (INIS)

    Nitzberg, K.E.; Broman, W.H.

    1992-01-01

    This paper reports that simulation models of the Prudhoe Bay Northwest Fault Block (NWFB) waterflood project, with core-plug-derived permeabilities, predicted that injected water would slump because of gravity segregation. Detailed analysis of surveillance logs and production data for one pattern identified tritium tracer breakthrough in surrounding producers without significant slumping. To duplicate the nearly horizontal movement of injected water, a k V /k H ratio that is an order of magnitude lower than previously modeled is required. This improved reservoir characterization led to revision of the reservoir management strategy for the NWFB

  5. Effect of Prudhoe Bay crude oil on the homing of coho salmon in marine waters

    International Nuclear Information System (INIS)

    Nakatani, R.E.; Nevissi, A.E.

    1991-01-01

    Resource managers and the fishing industry have expressed concern that a crude-oil spill occurring in the pathway of a salmon run may destroy the ability of the maturing salmon to reach the home stream. To address this concern, groups of mature 3-year-old and precocious 2-year-old coho salmon Oncorhynchus kisutch were tagged and exposed in seawater for 1 hr to sublethal concentration of Prudhoe Bay crude oil, dispersed oil, or seawater oil dispersant alone, and then were released in seawater about 5 km from their home stream. The results show that the coho salmon's homing success and speed of return to the home stream were not affected by any of the treatments. The longevity or holding tests, in which coho salmon were held in saltwater netpens after experimental treatments, showed that the larger 3-year-old coho salmon were more sensitive to the stress of confinement than the smaller 2-year-old fish

  6. The hepatotoxic potential of a Prudhoe Bay crude oil: effect on mouse liver weight and composition

    International Nuclear Information System (INIS)

    Khan, S.; Irfan, M.; Rahimtula, A.D.

    1987-01-01

    The hepatotoxic properties of a Prudhoe Bay Crude Oil (PBCO) were evaluated in mice. Administration of PBCO (5.0 m1/kg body wt, daily for 2 days) to mice resulted in an increase in (i) liver wet and dry weight, (ii) hepatic total proteins RNA, glycogen and lotal lipids, and (iii) individual lipids such as cholesterol, triglycerides and phospholipids. Hepatic protein biosynthesis, determined in vivo by administration of L-[ 14 C] Leucine was increased in PBCO exposed in mice. The rate of 3 H incorporation from 3 H 2 O was significantly enhanced in liver fatty acids, cholesterol, triglycerides and thus ultimately in total lipids. Also, an increase in 3 H incorporation was noticed in hepatic glycogen after PBCO administration. The results suggest that PBCO may induce hepatotoxicity by altering the intermediary metabolism of biochemical constituents. (author) 39 refs

  7. Prudhoe Bay causeways and the summer coastal movements of arctic cisco and least cisco

    International Nuclear Information System (INIS)

    Fechhelm, R.G.; Martin, L.R.; Gallaway, B.J.; Wilson, W.J.; Griffiths, W.B.

    1999-01-01

    The possible effects that two Prudhoe Bay causeways (the West Dock and the Endicott Causeways) may have on the alongshore feeding dispersal and migration of least cisco and arctic cisco from their overwintering grounds in the Colville River were analyzed. The gravel causeways, which extends seaward from the coast, are used as platforms in recovering offshore petroleum reserves and extracting seawater that is injected into subsurface oil reservoirs. Part 1 of the paper analyzed catch data for juvenile least cisco collected during the summers from 1985 to 1993. Part 2 of the paper used data from several mark-recapture studies to analyze rates of tag recovery in a Colville River commercial gill net fishery for subadult and adult ciscos. It was determined that during two of the four years in which juvenile least cisco were abundant in the study area, catch rates were much lower east of West Dock. This suggests that small fish traveling eastward along the coast failed to bypass the West Dock causeway. However, no such disparities were found in the Endicott Causeway. During the nine year study, the rates of release were examined for three areas of release. The contradicting effects of the two causeways were discussed in terms of their design and location. The West Dock was constructed within the dispersal range of a diadromous species, at the eastern end of a brackish-water lagoon system. The Endicott Causeway was constructed on a shallow-water shelf, was fitted with breaches and is constantly receiving freshwater discharge from the Sagavanirktok River. 44 refs., 3 tabs., 9 figs

  8. Toxicity of Prudhoe Bay crude oil to mallard duck (Anas Platyrhynchos) embryos

    International Nuclear Information System (INIS)

    Lusimbo, W.S.

    1999-01-01

    This thesis examined the rates and timing of mortality and hatchability of mallard duck embryos that have been exposed to Prudhoe Bay crude oil (PBCO). The objective was to identify any pathological abnormalities that may suggest that the chorioallantoic membrane (CAM) is a target organ of toxicity. The study involved the external application of PBCO to the eggshell to mimic the natural route of exposure. Embryo mortality was then determined at different days of incubation and the most sensitive age of incubation to oil was established. On the basis of initial results, the following 3 hypothesis were formulated: (1) the CAM is a target organ of oil toxicity, (2) injury to the CAM compromises its physiological role of calcium mobilization from the eggshell, and (3) oil exposure causes anemia and damage to red blood cells of mallard embryos. Data was compared with data reported in chicken embryos exposed to the same type of petroleum oil. It was shown that the toxic effects of PBCO to mallard duck embryos were similar to those found in chicken embryos. Oil-exposed embryos exhibited high mortality and reduced growth. Pathological changes in liver, kidneys and bursa of Fabricius, in oil-exposed mallard embryos were also similar to those of exposed chicken embryos. It was noted that this is the first study to recognize and describe pathological changes in the chorioallantoic membrane (CAM) of avian embryos exposed to petroleum oil. Lesions in the CAM were found in areas right beneath the oil on the egg shell and in areas distant from any such direct contact, suggesting that direct contact with the oil was not the main cause of injury to the CAM. The occurrence of lesions in CAM were highest immediately following exposure to PBCO. The lesions observed suggest two different kids of toxic effects, lethal injury to cells in various tissues, and alteration in the timing of organ development. The author notes that more remains to be learned regarding the toxic effects of

  9. Oilfield geothermal exploitation in China-A case study from the Liaohe oilfield in Bohai Bay Basin

    Science.gov (United States)

    Wang, Shejiao; Yao, Yanhua; Fan, Xianli; Yan, Jiahong

    2017-04-01

    The clean geothermal energy can play a huge role in solving the problem of severe smog in China as it can replace large coal-fired heating in winter. Chinese government has paid close attention on the development and utilization of geothermal energy. In the "13th Five-Year" plan, the geothermal development is included into the national plan for the first time. China is very rich in the medium and low-temperature geothermal resources, ranking first in the geothermal direct use in the world for a long time. The geothermal resources are mainly concentrated in sedimentary basins, especially in petroliferous basins distributed in North China (in North China, heating is needed in winter). These basins are usually close to the large- and medium-sized cities. Therefore, tapping oilfield geothermal energy have attracted a great attention in the last few years as the watercut achieved above 90% in most oilfields and significant progress has been made. In this paper, taking the Liaohe Oilfield in the Bohai Bay Basin as an example, we discussed the distribution and potential of the geothermal resources, discussed how to use the existed technology to harness geothermal energy more effectively, and forecasted the development prospect of the oilfield geothermal energy. By using the volumetric method, we calculated the geothermal resources of the Guantao Formation, Dongying Formation, Shahejie Formation and basement rock in the Liaohe depression. We tested the geothermal energy utilization efficiency in different conditions by applying different pump technologies and utilizing geothermal energy in different depth, such as shallow geothermal energy (0-200m), middle-deep depth geothermal energy (200-4000m), and oilfield sewage heat produced with oil production. For the heat pump systems, we tested the conventional heat pump system, high-temperature heat pump system, super high-temperature heat pump system, and gas heat pump system. Finally, based on the analysis of national policy

  10. Loess ecosystems of northern Alaska: Regional gradient and toposequence at Prudhoe Bay

    International Nuclear Information System (INIS)

    Walker, D.A.; Everett, K.R.

    1991-01-01

    Loess-dominated ecosystems cover ∼ 14% (11,000 km 2 ) of the Arctic Coastal Plain and much of the northern portion of the Arctic Foothills. Knowledge of this poorly known ecosystem is important for sound land-use planning of the expanding developments in the region and for understanding the paleoecological dynamics of eolian systems that once dominated much of northern Alaska. A conceptual alkaline-tundra toposequence includes eight common vegetation types and associated soils and vegetation downwind of the Sagavanirktok River. Properties of loess tundra important for land-use planning include: (1) its high ice content, which contributes to its susceptibility to thermokarst; (2) high salinities, which hamper revegetation efforts; and (3) presence of certain plant species such as Dryas intergrifolia, which are particularly sensitive to disturbance. The loess gradient provides a natural analogue for road dust, and extensive disturbance associated with oil-field development

  11. Mid-scale tests of in situ burning in a new wave tank at Prudhoe Bay, AK

    International Nuclear Information System (INIS)

    Buist, I.; McCourt, J.; Mullin, J.; Glover, N.; Hutton, C.; McHale, J.

    1998-01-01

    A series of mid-scale research burns with weathered Alaska North Slope crude, Milne Pt. crude and emulsion slicks were carried out in the fall of 1997 in Prudhoe Bay, Alaska. A suitable wave tank was developed for the in-situ burning tests. The objective was to determine the effects of oil type, emulsification, temperature and waves on in situ burning in Arctic open water conditions. More than 60 individual burns were conducted under various parameters including varying slick thickness, water content, wave energy, degree of weathering and oil type. Results showed that a spill of 60 per cent water emulsion of weathered Alaska North Slope crude was successfully burned in the highest waves tested, with an oil removal efficiency of 79 per cent, after treatment with emulsion breakers. A slick of 60 per cent water emulsion of weathered Milne Pt. crude was also successfully burned under the same conditions but without the addition of emulsion breakers. 10 refs., 1 tab., 13 figs

  12. Increased opercular rates of pink salmon (Oncorhynchus gorbuscha) fry after exposure to the eater-soluble fraction of Prudhoe Bay crude oil

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, R E [Chico State Univ., CA; Rice, S D

    1976-01-01

    The opercular rates of pink salmon (Oncorhynchus gorbuscha) fry were measured during 24-h exposure to sublethal concentrations of the water-soluble fraction of Prudhoe Bay crude oil. Opercular rates increased significantly for as long as 9 and 12 h after exposure to water-soluble fractions prepared from oil-water solutions of 2.83 and 3.46 ppM. The increases in rates were proportional to increases in dose. Recording changes in opercular rates appears to be a suitable method for detecting sublethal physiological effects of stress, because the observed changes occurred at approximately 20 percent of the 96 h-LC50.

  13. Cumulative impacts of an evolving oil-field complex on the distribution of calving caribou

    International Nuclear Information System (INIS)

    Nellemann, C.; Cameron, R.D.

    1998-01-01

    A study was conducted to examine the relationship between caribou density and road density as one means of assessing the reaction of caribou to activities associated with the evolving Prudhoe Bay oil-field complex in Alaska. Aerial surveys from 1987 to 1992 have shown that caribou density is inversely related to road density. The effects of avoidance were most apparent in preferred rugged terrain which are important habitats for foraging during the calving period. Female calves were found to be much more sensitive to surface development than adult males and yearlings. The biggest disturbances were caused by initial road construction and related facilities. The recent displacement of some calving activity within the Kuparuk Development area may result in heightened competition for forage, increased risk of predation, and lower productivity of the herd. 43 refs., 3 tabs., 3 figs

  14. SOHIO (Standard Oil Co. , Ohio) to sell Prudhoe gas to Northern Natural Gas Co

    Energy Technology Data Exchange (ETDEWEB)

    1979-08-20

    Sohio has agreed to sell Vertical Bar3: 2 trillion cu ft of its Prudhoe Bay gas to Northern Natural Gas Co. for delivery at a rate of 170 million cu ft/day when the proposed Alaska Highway gas pipeline is completed. With the exception of approx. 4 trillion cu ft of Sohio's reserves committed to Columbia Gas System Inc., the agreement accounts for the sale of all the 26.5-27 trillion cu ft of Prudhoe Bay reserves. The contract, which is subject to approval of the U.S. Federal Energy Regulatory Commission, allows Alaska to take its one-eighth royalty share of the gas in kind or cash. Columbia Gas is the only firm planning to purchase Prudhoe Bay gas that is not participating as an equity owner in the pipeline project. According to a Columbia spokesman, it is still uncertain whether the proposed gas pipeline will be built; and the fact that Columbia has not yet signed a final agreement with Sohio does not indicate any decreasing interest in Prudhoe Bay gas.

  15. Vegetation and Environmental Gradients of the Prudhoe Bay Region, Alaska,

    Science.gov (United States)

    1985-09-01

    Agricultural Experiment Station, Palmer Research Cen- ter, University of Alaska, analyzed the soil nutrients. Tom Boldin , technician at the I University of...misidentified of the extract utilized the Technicon Autoanalyzer taxa. Most of these have been noted in the anno- industrial method No. 94-70W...orthophosphate in tated checklist of plants (Appendix A). water and wastewater). Nitrogen was analyzed with an extracting solution of 2N HCI and utilized

  16. General oilfield driver improvement

    International Nuclear Information System (INIS)

    Johnson, G.

    1997-01-01

    The general oilfield driver improvement (GODI) course was discussed. The course is offered to truckers in the oil and gas industry to help reduce accidents and injuries. Oilfield trucking is one of the most accident and injury prone sectors in the Alberta economy. This paper presented Heck's Trucking company's experience in sending its employees on the course. Drivers were taught (1) the National safety code requirements, (2) Commercial Vehicle Safety Alliance requirements, (3) occupational health and safety concerns, (4) vehicle dimension and GVW restrictions, (5) hours of service regulations, (6) log book and pre-trip inspection requirements, (7) workplace hazardous material information, and (8) transportation of dangerous goods. Overall, the course was judged to provide excellent training before sending drivers into the field. The employee, the customer, and the company, all stand to benefit from having rigorous and uniform standards for all drivers in the oil and gas industry

  17. Embedded digital oilfield model

    Science.gov (United States)

    Korovin, Iakov S.; Boldyreff, Anton S.

    2017-10-01

    In modern hard conditions for the whole worldwide oil production industry the problem of increasing volumes of produced oil has recently become vital. This problem concerns the existing oilfields cause due to low crude oil prices the possibilities to drill new ones has almost disappeared. In this paper, we describe a novel approach of oil production enhancement, based on online procedures of all oil field data processing. The essence is that we have developed a dynamic oilfield model that allows to simultaneously handle the information, stored in tNavigator, Schlumberger ECLIPSE 100/300 and other `popular' formats in parallel. The model is developed on the basis of convolutional neural networks. An example of successful industrial experiment is depicted.

  18. Forecasting oilfield economic performance

    International Nuclear Information System (INIS)

    Bradley, M.E.; Wood, A.R.O.

    1994-01-01

    This paper presents a general method for forecasting oilfield economic performance that integrates cost data with operational, reservoir, and financial information. Practices are developed for determining economic limits for an oil field and its components. The economic limits of marginal wells and the role of underground competition receive special attention. Also examined is the influence of oil prices on operating costs. Examples illustrate application of these concepts. Categorization of costs for historical tracking and projections is recommended

  19. Risk and return in oilfield asset holdings

    Energy Technology Data Exchange (ETDEWEB)

    Kretzschmar, Gavin L.; Kirchner, Axel; Reusch, Hans [University of Edinburgh, College of Humanities and Social Sciences, The Management School (United Kingdom)

    2008-11-15

    Convention suggests that emerging market investment should provide commensurately lower risk or higher returns than comparable assets in developed countries. This study demonstrates that emerging markets contain regulatory specificities that challenge asset valuation model convergence and potentially invert risk return convention. 292 oilfield assets are used to provide evidence that, under upward oil prices, emerging markets are characterized by progressive state participation in oilfield cash flows. Specifically, this work advances the low oil price paradigm of prior oil and gas asset valuation studies and provides evidence that emerging market state participation terms limit the corporate value of globalization for the sector. (author)

  20. Risk and return in oilfield asset holdings

    International Nuclear Information System (INIS)

    Kretzschmar, Gavin L.; Kirchner, Axel; Reusch, Hans

    2008-01-01

    Convention suggests that emerging market investment should provide commensurately lower risk or higher returns than comparable assets in developed countries. This study demonstrates that emerging markets contain regulatory specificities that challenge asset valuation model convergence and potentially invert risk return convention. 292 oilfield assets are used to provide evidence that, under upward oil prices, emerging markets are characterized by progressive state participation in oilfield cash flows. Specifically, this work advances the low oil price paradigm of prior oil and gas asset valuation studies and provides evidence that emerging market state participation terms limit the corporate value of globalization for the sector. (author)

  1. Sensitivity of Plant Communities and Soil Flora to Seawater Spills, Prudhoe Bay, Alaska,

    Science.gov (United States)

    1983-09-01

    concentrate at the interface of foliolosa on the wet sites. the active layer and the permafrost and may in- Seven of the vascular plant taxa that developed... urease , protease, organic carbon and nitrogen. LE. Brown (1978) Effects of crude oil and diesel Journal of the Soil Science Society of America, oil

  2. Handling, treating and injecting of oilfield wastes

    International Nuclear Information System (INIS)

    Pippard, D.K.

    1997-01-01

    The waste management practices of the oil and gas industry in British Columbia were reviewed. Newalta is a waste management company that offers services to both the upstream (oilfield) and downstream (refined products) petroleum industries. The measures that this company has taken to comply with the new regulations in British Columbia were discussed. Issues regarding deep well disposal, oil and gas waste regulation, and liquid waste streams not authorized for disposal, were addressed. Oil and gas production waste liquids generated in British Columbia can be transported into Alberta for treatment and disposal under Alberta's hazardous wastes disposal legislation. The treatment of crude oil wastes, oilfield waste solids were also addressed. Solid wastes can be disposed of by in-situ treatment, by ex-situ, on-site treatment such as biodegradation and thermal treatment, and by ex-situ, off-site treatment

  3. The Environmental Impact of Oilfield Formation Water on a ...

    African Journals Online (AJOL)

    A comparative analysis of the physico-chemical parameters of treated oilfield formation water and that of a freshwater stream with no previous history of pollution from oil exploration activities was determined. The environmental impact resulting from the discharge of treated oilfield formation water into freshwater samples ...

  4. Maximization techniques for oilfield development profits

    International Nuclear Information System (INIS)

    Lerche, I.

    1999-01-01

    In 1981 Nind provided a quantitative procedure for estimating the optimum number of development wells to emplace on an oilfield to maximize profit. Nind's treatment assumed that there was a steady selling price, that all wells were placed in production simultaneously, and that each well's production profile was identical and a simple exponential decline with time. This paper lifts these restrictions to allow for price fluctuations, variable with time emplacement of wells, and production rates that are more in line with actual production records than is a simple exponential decline curve. As a consequence, it is possible to design production rate strategies, correlated with price fluctuations, so as to maximize the present-day worth of a field. For price fluctuations that occur on a time-scale rapid compared to inflation rates it is appropriate to have production rates correlate directly with such price fluctuations. The same strategy does not apply for price fluctuations occurring on a time-scale long compared to inflation rates where, for small amplitudes in the price fluctuations, it is best to sell as much product as early as possible to overcome inflation factors, while for large amplitude fluctuations the best strategy is to sell product as early as possible but to do so mainly on price upswings. Examples are provided to show how these generalizations of Nind's (1981) formula change the complexion of oilfield development optimization. (author)

  5. Applications of piezoelectric materials in oilfield services.

    Science.gov (United States)

    Goujon, Nicolas; Hori, Hiroshi; Liang, Kenneth K; Sinha, Bikash K

    2012-09-01

    Piezoelectric materials are used in many applications in the oilfield services industry. Four illustrative examples are given in this paper: marine seismic survey, precision pressure measurement, sonic logging-while-drilling, and ultrasonic bore-hole imaging. In marine seismics, piezoelectric hydrophones are deployed on a massive scale in a relatively benign environment. Hence, unit cost and device reliability are major considerations. The remaining three applications take place downhole in a characteristically harsh environment with high temperature and high pressure among other factors. The number of piezoelectric devices involved is generally small but otherwise highly valued. The selection of piezoelectric materials is limited, and the devices have to be engineered to withstand the operating conditions. With the global demand for energy increasing in the foreseeable future, the search for hydrocarbon resources is reaching into deeper and hotter wells. There is, therefore, a continuing and pressing need for high-temperature and high-coupling piezoelectric materials.

  6. Oilfield Flare Gas Electricity Systems (OFFGASES Project)

    Energy Technology Data Exchange (ETDEWEB)

    Rachel Henderson; Robert Fickes

    2007-12-31

    The Oilfield Flare Gas Electricity Systems (OFFGASES) project was developed in response to a cooperative agreement offering by the U.S. Department of Energy (DOE) and the National Energy Technology Laboratory (NETL) under Preferred Upstream Management Projects (PUMP III). Project partners included the Interstate Oil and Gas Compact Commission (IOGCC) as lead agency working with the California Energy Commission (CEC) and the California Oil Producers Electric Cooperative (COPE). The project was designed to demonstrate that the entire range of oilfield 'stranded gases' (gas production that can not be delivered to a commercial market because it is poor quality, or the quantity is too small to be economically sold, or there are no pipeline facilities to transport it to market) can be cost-effectively harnessed to make electricity. The utilization of existing, proven distribution generation (DG) technologies to generate electricity was field-tested successfully at four marginal well sites, selected to cover a variety of potential scenarios: high Btu, medium Btu, ultra-low Btu gas, as well as a 'harsh', or high contaminant, gas. Two of the four sites for the OFFGASES project were idle wells that were shut in because of a lack of viable solutions for the stranded noncommercial gas that they produced. Converting stranded gas to useable electrical energy eliminates a waste stream that has potential negative environmental impacts to the oil production operation. The electricity produced will offset that which normally would be purchased from an electric utility, potentially lowering operating costs and extending the economic life of the oil wells. Of the piloted sites, the most promising technologies to handle the range were microturbines that have very low emissions. One recently developed product, the Flex-Microturbine, has the potential to handle the entire range of oilfield gases. It is deployed at an oilfield near Santa Barbara to run on waste gas

  7. Market risks and oilfield ownership - Refining oil and gas disclosures

    International Nuclear Information System (INIS)

    Kretzschmar, Gavin L.; Hatherly, David; Misund, Bard

    2007-01-01

    Market risk exposures of balance sheet asset values are becoming an increasingly important accounting issue. In oil and gas, oilfield exposures to oil prices are specific and contractual, presenting a contingency problem for investors, financial analysts, standard setting bodies and government agencies. Our paper uses an extensive sample of 292 oilfields to provide evidence that the US Securities and Exchange Commission (SEC) supplementary disclosures do not capture the price sensitivities of oil and gas disclosures implicit in the two main forms of oilfield ownership, concession and production sharing contracts (PSCs). Current asset disclosures neither distinguish between global variations in oilfield ownership terms, nor on market risk implications for the value of oilfield assets. Importantly, we show that unlike concessions, reserve and production disclosures vary in response to oil price movements for PSC regimes. Our results highlight the need to differentiate PSC disclosures from concession fields, and to fully reflect price risks implicit in oilfield ownership contracts. We extend findings by Rajgopal [1999. Early evidence on the informativeness of the SEC's market risk disclosures: the case of commodity price risk exposure of oil and gas producers. The Accounting Review 74, 251-280] and propose refinements to capture market risk in financial reporting. (author)

  8. Exploitation and Utilization of Oilfield Geothermal Resources in China

    Directory of Open Access Journals (Sweden)

    Shejiao Wang

    2016-09-01

    Full Text Available Geothermal energy is a clean, green renewable resource, which can be utilized for power generation, heating, cooling, and could effectively replace oil, gas, and coal. In recent years, oil companies have put more efforts into exploiting and utilizing geothermal energy with advanced technologies for heat-tracing oil gathering and transportation, central heating, etc., which has not only reduced resource waste, but also improved large-scale and industrial resource utilization levels, and has achieved remarkable economic and social benefits. Based on the analysis of oilfield geothermal energy development status, resource potential, and exploitation and utilization modes, the advantages and disadvantages of harnessing oilfield geothermal resource have been discussed. Oilfield geothermal energy exploitation and utilization have advantages in resources, technical personnel, technology, and a large number of abandoned wells that could be reconstructed and utilized. Due to the high heat demand in oilfields, geothermal energy exploitation and utilization can effectively replace oil, gas, coal, and other fossil fuels, and has bright prospects. The key factors limiting oilfield geothermal energy exploitation and utilization are also pointed out in this paper, including immature technologies, lack of overall planning, lack of standards in resource assessment, and economic assessment, lack of incentive policies, etc.

  9. Horizontal well technology in the oilfield of China

    Energy Technology Data Exchange (ETDEWEB)

    Xiange, L.; Shangqi, L.; Zhixiang, J. [Research Institute of Petroleum Exploration and Development (China)

    1998-12-31

    The current state of horizontal well development and enhanced recovery technology in the onshore oilfields of China is described. The paper includes discussion of technology developed for light oil reservoirs, heavy oil reservoirs with thermal recovery, low permeability reservoirs and high water flooding reservoirs. Examples of various applications of the technology are described. 3 refs., 5 tabs., 11 figs.

  10. Causes and preventive management of scale formation in oilfield ...

    African Journals Online (AJOL)

    ... removal of at least one scaling component from the system, pH reduction, choosing a surface that resists scale adhesion, application of physical fields example magnetic or electrostatic, the use of scale inhibitors and proactive application of scale prediction models or soft wares. Keywords: Scale formation, oilfield systems ...

  11. Comparison of Short and Long Versions of the Prudhoe Cognitive Function Test and the K-BIT in Participants with Intellectual Impairment

    Science.gov (United States)

    Tyrer, Stephen P.; Wigham, Ann; Cicchetti, Domenic; Margallo-Lana, Marisa; Moore, P. Brian; Reid, Barbara E.

    2010-01-01

    The Prudhoe Cognitive Function Test (PCFT) directly measures the cognitive abilities of people with intellectual impairment. This study examined the relationship between this instrument and the Kaufman Brief Intelligence Test (K-BIT) and two shorter versions of the same scale. High correlations between the verbal and performance sections of the…

  12. Nuclear Tools For Oilfield Logging-While-Drilling Applications

    International Nuclear Information System (INIS)

    Reijonen, Jani

    2011-01-01

    Schlumberger is an international oilfield service company with nearly 80,000 employees of 140 nationalities, operating globally in 80 countries. As a market leader in oilfield services, Schlumberger has developed a suite of technologies to assess the downhole environment, including, among others, electromagnetic, seismic, chemical, and nuclear measurements. In the past 10 years there has been a radical shift in the oilfield service industry from traditional wireline measurements to logging-while-drilling (LWD) analysis. For LWD measurements, the analysis is performed and the instruments are operated while the borehole is being drilled. The high temperature, high shock, and extreme vibration environment of LWD imposes stringent requirements for the devices used in these applications. This has a significant impact on the design of the components and subcomponents of a downhole tool. Another significant change in the past few years for nuclear-based oilwell logging tools is the desire to replace the sealed radioisotope sources with active, electronic ones. These active radiation sources provide great benefits compared to the isotopic sources, ranging from handling and safety to nonproliferation and well contamination issues. The challenge is to develop electronic generators that have a high degree of reliability for the entire lifetime of a downhole tool. LWD tool testing and operations are highlighted with particular emphasis on electronic radiation sources and nuclear detectors for the downhole environment.

  13. Multiphase pumping: indoor performance test and oilfield application

    Science.gov (United States)

    Kong, Xiangling; Zhu, Hongwu; Zhang, Shousen; Li, Jifeng

    2010-03-01

    Multiphase pumping is essentially a means of adding energy to the unprocessed effluent which enables the liquid and gas mixture to be transported over a long distances without prior separation. A reduction, consolidation, or elimination of the production infrastructure, such as separation equipments and offshore platforms can be developed more economically. Also it successfully lowed the backpressure of wells, revived dead wells and improved the production and efficiency of oilfield. This paper reviews the issues related to indoor performance test and an oilfield application of the helico-axial multiphase pump designed by China University of Petroleum (Beijing). Pump specification and its hydraulic design are given. Results of performance testing under different condition, such as operational speed and gas volume fraction (GVF) etc are presented. Experimental studies on combination of theoretical analysis showed the multiphase pump satisfies the similitude rule, which can be used in the development of new MPP design and performance prediction. Test results showed that rising the rotation speed and suction pressure could better its performance, pressure boost improved, high efficiency zone expanding and the flow rate related to the optimum working condition increased. The pump worked unstable as GVF increased to a certain extent and slip occurred between two phases in the pump, creating surging and gas lock at a high GVF. A case of application in Nanyang oilfield is also studied.

  14. a mathematical model for predicting output in an oilfield in the niger

    African Journals Online (AJOL)

    eobe

    resultant model was found to have greater utility in predicting oil field output as it produced less residual. The ... decision making by the oilfield manager is facilitated by reliable ... Scaling laws from percolation theory was used to predict oilfield ...

  15. Soil gas radon and thoron measurements in some Venezuelan oilfields

    International Nuclear Information System (INIS)

    Fernandez, Daniel Palacios; Yininber Avila; Teixeira, Diana; Sajo-Bohus, Laszlo; Greaves, Eduardo; Barros, Haydn; Fusella, Emidio; Salas, Johnny; Fernandez, Guillermo; Bolivar, Manuel; Regalado, Jimmy

    2016-01-01

    Radon and thoron concentrations in soil gas were studied in some Venezuelan oilfields using passive and active methods. In some cases, investigations indicated a strong correlation between oil production areas and the intensity of radon signals, while in others a decrease in radon concentration was observed. This behavior was explained on the basis of different geological structures of the associated reservoir traps. Geological faults associated with petroleum systems were well recognized by the radon and thoron anomalies. Possible conduits and sources responsible for the occurrence of natural gas in a river and in an aquifer were identified and localized. (author)

  16. Water conservation and allocation guideline for oilfield injection

    International Nuclear Information System (INIS)

    2006-01-01

    This paper was prepared as a guide for regulatory agencies and developers using non-saline water sources in enhanced oil recovery (EOR) schemes. A systems approach was used to achieve specific environmental outcomes that adhered to the Water Conservation and Allocation Policy for Oilfield Injection. The guide was applicable to licence renewal applications for projects operating and licensed to use non-saline water resources, as well as new licence applications for oilfield injection use. The guide provided recommended water conservation practices and application requirements, and outlined regulatory procedures and steps for obtaining a Water Act licence. The guideline was prepared to eliminate the use of non-saline water in EOR projects where feasible alternatives existed, as well as to identify areas with water shortages and reduce the use of non-saline water. The guide included monitoring and reporting requirements to improve the evaluation of water use practices and outlined current initiatives to address water conservation and research. It was concluded that outcomes from the program will include reliable quality water supplies for a sustainable economy, healthy aquatic ecosystems, and safe, secure drinking water supplies for Albertans. 3 tabs., 5 figs

  17. Smart stores: old oilfield mainstays teach themselves new tricks

    International Nuclear Information System (INIS)

    Collison, M.

    2000-01-01

    The place of field service equipment stores in the western Canadian oilpatch is described, emphasizing the influence of global economic cycles triggered by the erratic nature of oil and gas commodity prices, that control the fortunes of this sector of the oil industry. The trials and tribulations of C. E. Franklin Ltd and NWP Industries are cited as examples of how oilfield service stores attempt to cope with the ebb and flow of oil prices which dictate the fortunes of the oil industry, which in turn determines the demand for what the field service companies have to offer. Changes in product cycles are also exercising a significant influence on the state of the sector. Computer hardware and software services provided by service companies have been the most recent causes of increased sales and job creation; the next step eagerly anticipated is e-commerce. There is a great deal of confidence among oilfield service service companies that e-commerce will change the way business is done in virtually every industry in the world and companies like Franklin and NWP are gearing up to leveraging their infrastructure (i. e. their staff) via Internet technology. Taking care of the anticipated 17,000 to 18,000 new wells that will be drilled in western Canada is the most immediate challenge; in the short-term, coming out of lean times, lack of cash flow will make it extremely difficult to take care of the increased activity

  18. A software system for oilfield facility investment minimization

    International Nuclear Information System (INIS)

    Ding, Z.X.; Startzman, R.A.

    1996-01-01

    Minimizing investment in oilfield development is an important subject that has attracted a considerable amount of industry attention. One method to reduce investment involves the optimal placement and selection of production facilities. Because of the large amount of capital used in this process, saving a small percent of the total investment may represent a large monetary value. The literature reports algorithms using mathematical programming techniques that were designed to solve the proposed problem in a global optimal manner. Owing to the high-computational complexity and the lack of user-friendly interfaces for data entry and results display, mathematical programming techniques have not been given enough attention in practice. This paper describes an interactive, graphical software system that provides a global optimal solution to the problem of placement and selection of production facilities in oil-field development processes. This software system can be used as an investment minimization tool and a scenario-study simulator. The developed software system consists of five basic modules: (1) an interactive data-input unit, (2) a cost function generator, (3) an optimization unit, (4) a graphic-output display, and (5) a sensitivity-analysis unit

  19. The regulatory environment for drilling and oilfield waste disposal and remediation in Alberta

    International Nuclear Information System (INIS)

    MacLachlan, L.J.; Stimpson, S.

    1999-01-01

    The legislative basis of regulation of all aspects of oilfield waste, including all oil and gas, oil sands, and oilfield waste management facility operations in Alberta is discussed. The appropriate waste management practices for the upstream petroleum industry and all waste stream associated with the petroleum industry are outlined. Major topics discussed include: (1) the roles and the jurisdictions of the Alberta Energy and Utilities Board (EUB) and Alberta Environmental Protection (AEP), (2) drilling waste and oilfield waste disposal, EUB guides 50 and 58, (3) wellsite abandonment and reclamation of wellsites, (4) spills and contaminated sites, (5) environmental offences, enforcement, penalties and defences

  20. Reserve growth in German oilfields; Reservenwachstum in deutschen Erdoelfeldern

    Energy Technology Data Exchange (ETDEWEB)

    Schwietzer, Curt-Albert [RWE Dea AG, Hamburg (Germany)

    2013-07-15

    In the English language use, the term ''Reserve Growth'' describes the fact that in most cases at the start of a field development the estimated ultimate recovery of reserves (EUR) is smaller than it will turn out later by production history. Although this phenomenon of reserve growth gives hints for new reserves in mature hydrocarbon provinces, it has hardly been investigated. In the few existing studies about this issue it is shown that reserve growth is, in the majority of cases, based on factors like the application of improved methods to increase the recovery factor as well as on optimization of the reservoir development by precise modeling and simulation as well as on changing of the reserve classification. Different combinations of these factors affect the changes of reserves during the life of the reservoir. This study investigates the reserve trend of 35 German oilfields over the last 40 to 50 years. Most of them register reserve growth; in some cases even a factor > 10 was achieved. On average, this reserve growth factor can be calculated as 3. A similar study about US American onshore oilfields was carried out for the first time by Arrington; this was, at a later time, revised by the USGS. In the article, Mahendra K. Verma developed the ''Growth Function'' by regression. The ''Growth Function'' describes the changes of proved reserves during the life of an oil reservoir. It indicates that ten years after production start, the reserves increased by three times, whereas the largest proportion of this increase occurred in the first three years. During the next 30 years, the reserves growth factor increased by up to 5.3; at the point of 95 years of production it accumulated to 6.9. In the case of the analysed German oilfields, the reserve growth behaviour was similar. Corresponding to the ''Growth Function'' after 40 years of production, it achieved a factor of 5 and reached a

  1. Comparative experiments on polymer degradation technique of produced water of polymer flooding oilfield

    Science.gov (United States)

    Chen, Rong; Qi, Mei; Zhang, Guohui; Yi, Chenggao

    2018-02-01

    The application of polymer flooding technology in oilfields can result in polymer content increased in produced water. This increasing made produced water quality become poor. The efficiency of produced water processing decreased significantly. Processed water quality seriously exceeded criterion’s stipulation. The presence of the polymer in produced water is the main reason for more difficulties in processing of produced water, therefore the polymer degradation technology is a key coefficient in produced water processing for polymer flooding oilfields. We evaluated several physical and chemical polymer degradation methods with the solution of separated water from polymer flooding oilfields and hydrolyzed polyacrylamide. The experiment results can provide a basis for produced water processing technologies application in polymer flooding oilfields.

  2. SPECTROGRAPHIC DETERMINATION OF BERYLLIUM IN OILFIELD WATERS USING A PLASMA ARC

    Energy Technology Data Exchange (ETDEWEB)

    Collins, A. G.; Pearson, C. A.

    1963-10-15

    Geochemical studies of the distribution of the trace, minor, and major constituents of oilfield waters aid in the exploration for petroleum and other minerals, determination of the origin and distribution of oilfield waters and petroleum, and location of casing leaks and of water pollution sources. The determination of the beryllium and related data should be useful in these studies. An emission spectrographic method utilizing a plasma arc assembly for determining beryllium in oilfield waters, with a sensitivity permitting detection of less than 1 ppb, was developed. Beryllium was extracted from synthetic and natural oilfield waters with chloroform and acetylacetone. The extracts were aspirated directly into the plasma arc, and the beryllium emission intensity was recorded on photographic plates. (auth)

  3. Numerical Simulation on Flow Field of Oilfield Three-Phase Separator

    Directory of Open Access Journals (Sweden)

    Yong-tu Liang

    2013-01-01

    Full Text Available The conventional measurement method can no longer guarantee the accuracy requirement after the oilfield development entering high water cut stage, due to the water content and gas phase in the flow. In order to overcome the impact of measurement deviation the oilfield production management, the flow field of three-phase separator is studied numerically in this paper using Fluent 6.3.26. Taking into consideration the production situation of PetroChina Huabei Oilfield and the characteristics of three-phase separator, the effect of internal flow status as well as other factors such as varying flow rate, gas fraction, and water content on the separation efficiency is analyzed. The results show that the separation efficiencies under all operation conditions are larger than 95%, which satisfy the accuracy requirement and also provide the theoretical foundation for the application of three-phase separators at oilfields.

  4. Microbial dynamics in petroleum oilfields and their relationship with physiological properties of petroleum oil reservoirs.

    Science.gov (United States)

    Varjani, Sunita J; Gnansounou, Edgard

    2017-12-01

    Petroleum is produced by thermal decay of buried organic material over millions of years. Petroleum oilfield ecosystems represent resource of reduced carbon which favours microbial growth. Therefore, it is obvious that many microorganisms have adapted to harsh environmental conditions of these ecosystems specifically temperature, oxygen availability and pressure. Knowledge of microorganisms present in ecosystems of petroleum oil reservoirs; their physiological and biological properties help in successful exploration of petroleum. Understanding microbiology of petroleum oilfield(s) can be used to enhance oil recovery, as microorganisms in oil reservoirs produce various metabolites viz. gases, acids, solvents, biopolymers and biosurfactants. The aim of this review is to discuss characteristics of petroleum oil reservoirs. This review also provides an updated literature on microbial ecology of these extreme ecosystems including microbial origin as well as various types of microorganisms such as methanogens; iron, nitrate and sulphate reducing bacteria, and fermentative microbes present in petroleum oilfield ecosystems. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. An application of sedimentation simulation in Tahe oilfield

    Science.gov (United States)

    Tingting, He; Lei, Zhao; Xin, Tan; Dongxu, He

    2017-12-01

    The braided river delta develops in Triassic low oil formation in the block 9 of Tahe oilfield, but its sedimentation evolution process is unclear. By using sedimentation simulation technology, sedimentation process and distribution of braided river delta are studied based on the geological parameters including sequence stratigraphic division, initial sedimentation environment, relative lake level change and accommodation change, source supply and sedimentary transport pattern. The simulation result shows that the error rate between strata thickness of simulation and actual strata thickness is small, and the single well analysis result of simulation is highly consistent with the actual analysis, which can prove that the model is reliable. The study area belongs to braided river delta retrogradation evolution process, which provides favorable basis for fine reservoir description and prediction.

  6. Thirteen years of exploitation with constant oilfield pressure

    Energy Technology Data Exchange (ETDEWEB)

    Dontov-Danu, Gh

    1966-12-01

    The paper describes a restoring and maintaining reservoir pressure by gas injection in two blocks of the Dacian stratum at Buscani. At the beginning of gas injection, the wells produced in gas lift and the crude oil flows were markedly decreasing. After about 6 months of injection the reservoir pressure has been restored, the wells flowed. This system allows constant crude oil flows for long periods. The oilfield recovery factor until December 31, 1965, is 51% i.e. by 150% higher than expected in the case of an exploitation without gas injection. This increase represents the extra crude oil and gasoline production obtained as a result of the application of the reservoir pressure maintenance process. The average consumption of working agent has been of 382 cu m gas per ton of additionally extracted crude oil.

  7. Advanced treatment and reuse system developed for oilfield process water

    Energy Technology Data Exchange (ETDEWEB)

    Conroy, Kevin

    2011-01-15

    An innovative plant to treat oilfield produced wastewater is being constructed in Trinidad and Tobago following recent regulations and industrial water supply challenges. The 4,100m3/day treatment system, developed by Golder Associates, will produce water for industrial reuse and effluent that meets new regulations. The treatment stages include: oil-water separation by gravity, equalization with a two-day capacity basin, dissolved air flotation, cooling, biotreatment/settling with immobilized cell bioreactors (ICB) technology, prefiltration/reverse osmosis and effluent storage/transfer. This advanced system will provide several important benefits including the elimination of inland discharge of minimally-treated water and the reduction of environmental and public health concerns. In addition, it will provide a new source of industrial water, resulting in a decrease in demand for fresh water. The success of this plant could lead to additional facilities in other oil field locations, expanding economic and environmental benefits of water reuse.

  8. Design of 3D simulation engine for oilfield safety training

    Science.gov (United States)

    Li, Hua-Ming; Kang, Bao-Sheng

    2015-03-01

    Aiming at the demand for rapid custom development of 3D simulation system for oilfield safety training, this paper designs and implements a 3D simulation engine based on script-driven method, multi-layer structure, pre-defined entity objects and high-level tools such as scene editor, script editor, program loader. A scripting language been defined to control the system's progress, events and operating results. Training teacher can use this engine to edit 3D virtual scenes, set the properties of entity objects, define the logic script of task, and produce a 3D simulation training system without any skills of programming. Through expanding entity class, this engine can be quickly applied to other virtual training areas.

  9. Treatment of NORM contaminated soil from the oilfields.

    Science.gov (United States)

    Abdellah, W M; Al-Masri, M S

    2014-03-01

    Uncontrolled disposal of oilfield produced water in the surrounding environment could lead to soil contamination by naturally occurring radioactive materials (NORM). Large volumes of soil become highly contaminated with radium isotopes ((226)Ra and (228)Ra). In the present work, laboratory experiments have been conducted to reduce the activity concentration of (226)Ra in soil. Two techniques were used, namely mechanical separation and chemical treatment. Screening of contaminated soil using vibratory sieve shaker was performed to evaluate the feasibility of particle size separation. The fractions obtained were ranged from less than 38 μm to higher than 300 μm. The results show that (226)Ra activity concentrations vary widely from fraction to fraction. On the other hand, leaching of (226)Ra from soil by aqueous solutions (distilled water, mineral acids, alkaline medias and selective solvents) has been performed. In most cases, relatively low concentrations of radium were transferred to solutions, which indicates that only small portions of radium are present on the surface of soil particles (around 4.6%), while most radium located within soil particles; only concentrated nitric acid was most effective where 50% of (226)Ra was removed to aqueous phase. However, mechanical method was found to be easy and effective, taking into account safety procedures to be followed during the implementation of the blending and homogenization. Chemical extraction methods were found to be less effective. The results obtained in this study can be utilized to approach the final option for disposal of NORM contaminated soil in the oilfields. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Estimate of Hot Dry Rock Geothermal Resource in Daqing Oilfield, Northeast China

    OpenAIRE

    Guangzheng Jiang; Yi Wang; Yizuo Shi; Chao Zhang; Xiaoyin Tang; Shengbiao Hu

    2016-01-01

    Development and utilization of deep geothermal resources, especially a hot dry rock (HDR) geothermal resource, is beneficial for both economic and environmental consideration in oilfields. This study used data from multiple sources to assess the geothermal energy resource in the Daqing Oilfield. The temperature logs in boreholes (both shallow water wells and deep boreholes) and the drilling stem test temperature were used to create isothermal maps in depths. Upon the temperature field and the...

  11. Forecast of oil reserves and production in Daqing oilfield of China

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Xu; Zhang, Baosheng; Feng, Lianyong [The School of Business Administration, China University of Petroleum-Beijing, 18 Fuxue Road, Changping, Beijing (China); Hoeoek, Mikael [Global Energy Systems, Department of Physics and Astronomy, Uppsala University, Box 535, SE-751 21 Uppsala (Sweden)

    2010-07-15

    As China' largest oilfield, Daqing is of great importance to China, this paper analyzes the status of the Daqing oilfield and forecasts its ultimate recoverable reserves by use of the URR model. The forecast results are presented for three scenarios which show that the ultimate recoverable reserves in Daqing oilfield are 3574.0 million tons in the optimistic scenario, 3169.3 million in the base case scenario and 3033.3 million in the pessimistic scenario, respectively. A system dynamics model is established and the quantitative relationships between variables in the model are determined. Total oil production, remaining recoverable reserves, annual newly discovered reserves, and the degree of reserves recovery before 2060 are simulated under the three scenarios by use of the system dynamics model. The forecast results show that the future oil production in Daqing oilfield will continue declining, under the base case scenario, from 41.6 million tons in 2007 to 8.0 million tons in 2060. For Chinese policy-makers, it is worth paying attention to the problem of whether oil production in new oilfields can effectively make up for the decline in production of the large, old oilfields. (author)

  12. The Impact of Tax Shocks and Oil Price Volatility on Risk - A Study of North Sea Oilfield Projects

    OpenAIRE

    Kretzschmar, Gavin Lee; Moles, Peter

    2006-01-01

    We examine the impact of market volatility and increased fiscal take on risk in strategic natural resource projects. An increase in 2006 UK oilfield taxation is used as a natural experiment for assessing the impact of a fiscal increase on oilfield projects comprising 73% of UK reserves. Stochastic cash flow at risk models combine market volatility and tax-take at the oilfield level to extend earlier North Sea studies. We demonstrate that a 10% Secondary tax increase in a composite UKCS fiscal...

  13. Integrated inventory ranking system for oilfield equipment industry

    Directory of Open Access Journals (Sweden)

    Jalel Ben Hmida

    2014-01-01

    Full Text Available Purpose: This case study is motivated by the subcontracting problem in an oilfield equipment and service company where the management needs to decide which parts to manufacture in-house when the capacity is not enough to make all required parts. Currently the company is making subcontracting decisions based on management’s experience. Design/methodology/approach: Working with the management, a decision support system (DSS is developed to rank parts by integrating three inventory classification methods considering both quantitative factors such as cost and demand, and qualitative factors such as functionality, efficiency, and quality. The proposed integrated inventory ranking procedure will make use of three classification methods: ABC, FSN, and VED. Findings: An integration mechanism using weights is developed to rank the parts based on the total priority scores. The ranked list generated by the system helps management to identify about 50 critical parts to manufacture in-house. Originality/value: The integration of all three inventory classification techniques into a single system is a unique feature of this research. This is important as it provides a more inclusive, big picture view of the DSS for management’s use in making business decisions.

  14. Development of oilfield facilities on a nature reserve

    International Nuclear Information System (INIS)

    Long, P.J.; Long, V.L.

    1991-01-01

    This paper reports on Airlie Island which is a small (26 hectare) sand cay, located 35km north of Onslow in Western Australia. In common with other islands in the region, Airlie is a nesting site for seabirds and turtles, but its two primary conservation resources are the large Wedge-tailed Shearwater rookery which covers 64% of the island and an endemic skink species. Its conservation values have prompted the Western Australian State Government to declare the entire island a nature reserve set apart for the preservation of flora and fauna. In 1987 Western Mining Corporation Pty Ltd. developed the South Pepper and North herald oilfields and part of this development included the siting of an oil terminal on Airlie Island. It may be expected that the conservation resources of the island and the Company's requirements for land would be incompatible. However, a careful study of the local environment and the creation of a detailed plan to manage this environment resulted in an acceptable compromise

  15. Harmonization of industrial and oilfield waste management issues in Alberta

    International Nuclear Information System (INIS)

    Halla, S.

    1999-01-01

    There has been an ongoing discussion concerning the harmonization of waste management requirements within Alberta between the Alberta Energy and Utilities Board (EUB) and Alberta Environment (AENV), with the ultimate goal of publishing a memorandum of understanding (MOU) that will lay out the division of responsibilities between the two authorities on this matter. An overview is included of waste management in Alberta and of the harmonization agreements attained to date, with a stress on oil field waste issues. The EUB and AENV developed a MOE on the harmonization of waste management in Alberta, and a discussion is made of the concept of equivalency, which is used in the development of 'EUB guide 58: oilfield waste management requirements for the upstream petroleum industry' and will be a guiding principle for the MOU. Although the EUB's processes for waste management will not be exactly the same as AENV's, the EUB has made the commitment that, as a minimum, the requirements will provide the same level of environmental protection and public safety equivalent to that provided by AENV

  16. Cost-efficient remediation of an upstream oilfield battery site

    Energy Technology Data Exchange (ETDEWEB)

    Siebert, L.D. [Imperial Oil Resources Canada, Calgary, AB (Canada); Bedard, G.; Pouliot, M.; Soucy, F.; Faucher, C.; Corbin, R. [Biogenie Inc., Quebec City, PQ (Canada)

    2003-07-01

    The soil at an oilfield battery site, located 18 kilometres (km) northwest of Devon, Alberta has been contaminated with crude oil and salt, following years of operation. Surrounding the site is flat farmland intended for future agricultural production. A remedial program aimed at complying with Tier I criteria of the Alberta Soil and Water Quality Guidelines for Hydrocarbons at Upstream Oil and Gas Facilities (ASWQG) of Alberta Environment, was developed and implemented. Characterization of the site was carried out in 1997 to delineate a salt plume, followed by a second sampling campaign in 1999, which all together revealed three impacted areas. A supplementary characterization was performed in 2001 by Biogenie in an effort to better determine the nature and level of petroleum contamination and more accurately evaluate the volume of contaminated soil. A three-dimensional Visualization software integrating a Kriging geostatistical model was used for this purpose. The results indicated that an estimated 8,800 cubic metres of contaminated soil would need to be excavated and treated. The next phase involved an evaluation of the various remedial options, which was accomplished using a biotreatability study. The remediation program selected involved the excavation of the contaminated soil and segregation of source material, the ex-situ Biopile treatment of the source material to meet Class II landfill criteria, and the ex-situ Biopile treatment of the contaminated soil followed by its use as backfill on site. The biotreatability study proved to be a strategic tool in the remediation effort. 1 tab., 2 figs.

  17. Integrating Carbon Flux Measurements with Hydrologic and Thermal Responses in a Low Centered Ice-Wedge Polygon near Prudhoe Bay, AK

    Science.gov (United States)

    Larson, T.; Young, M.; Caldwell, T. G.; Abolt, C.

    2014-12-01

    Substantial attention is being devoted to soil organic carbon (SOC) dynamics in Polar Regions, given the potential impacts of CO2 and methane (CH4) release into the atmosphere. In this study, which is part of a broader effort to quantify carbon loss pathways in patterned Arctic permafrost soils, CH4 and CO2 flux measurements were recorded from a site approximately 30 km south of Deadhorse, Alaska and 1 km west of the Dalton Highway. Samples were collected in late July, 2014 using six static flux chambers that were located within a single low-centered ice-wedge polygon. Three flux chambers were co-located (within a 1 m triangle of each other) near the center of the polygon and three were co-located (along a 1.5 m line) on the ridge adjacent to a trough. Soil in the center of the polygon was 100% water saturated, whereas water saturation measured on the ridge ranged between 25-50%. Depth to ice table was approximately 50 cm near the center of the polygon and 40 cm at the ridge. Temperature depth probes were installed within the center and ridge of the polygon. Nine gas measurements were collected from each chamber over a 24 h period, stored in helium-purged Exetainer vials, shipped to a laboratory, and analyzed using gas chromatography. Measured cumulative methane fluxes were linear over the 24 h period demonstrating constant methane production, but considerable spatial variability in flux was observed (0.1 to 4.7 mg hr-1 m-2 in polygon center, and 0.003 to 0.36 mg hr-1m-2 on polygon ridge). Shallow soil temperatures varied between 1.3 and 9.8oC in the center and 0.6 to 7.5oC in the rim of the polygon. Air temperatures varied between 1.3 and 4.6oC. CO2 fluxes were greater than methane fluxes and more consistent at each co-location; ranging from 21.7 to 36.6 mg hr-1 m-2 near the polygon centers and 3.5 to 29.1 mg hr-1 m-2 in the drier polygon ridge. Results are consistent with previous observations that methanogenesis is favored in a water saturated active layer. The independence of CH4 and CO2 fluxes suggests that different mechanisms may affect their formation and transport. Ongoing work on DOC and acetate concentrations may further elucidate the source of CH4 and CO2 flux. Results will be used to benchmark vertical SOC transport and active layer dynamics models, and then integrated into a Lidar-based geomorphic model for ice wedge polygon terrain.

  18. Risk assessment of nonhazardous oil-field waste disposal in salt caverns

    International Nuclear Information System (INIS)

    Elcock, D.

    1998-01-01

    Salt caverns can be formed in underground salt formations incidentally as a result of mining or intentionally to create underground chambers for product storage or waste disposal. For more than 50 years, salt caverns have been used to store hydrocarbon products. Recently, concerns over the costs and environmental effects of land disposal and incineration have sparked interest in using salt caverns for waste disposal. Countries using or considering using salt caverns for waste disposal include Canada (oil-production wastes), Mexico (purged sulfates from salt evaporators), Germany (contaminated soils and ashes), the United Kingdom (organic residues), and the Netherlands (brine purification wastes). In the US, industry and the regulatory community are pursuing the use of salt caverns for disposal of oil-field wastes. In 1988, the US Environmental Protection Agency (EPA) issued a regulatory determination exempting wastes generated during oil and gas exploration and production (oil-field wastes) from federal hazardous waste regulations--even though such wastes may contain hazardous constituents. At the same time, EPA urged states to tighten their oil-field waste management regulations. The resulting restrictions have generated industry interest in the use of salt caverns for potentially economical and environmentally safe oil-field waste disposal. Before the practice can be implemented commercially, however, regulators need assurance that disposing of oil-field wastes in salt caverns is technically and legally feasible and that potential health effects associated with the practice are acceptable. In 1996, Argonne National Laboratory (ANL) conducted a preliminary technical and legal evaluation of disposing of nonhazardous oil-field wastes (NOW) into salt caverns. It investigated regulatory issues; the types of oil-field wastes suitable for cavern disposal; cavern design and location considerations; and disposal operations, closure and remediation issues. It determined

  19. Risk assessment of nonhazardous oil-field waste disposal in salt caverns.

    Energy Technology Data Exchange (ETDEWEB)

    Elcock, D.

    1998-03-10

    Salt caverns can be formed in underground salt formations incidentally as a result of mining or intentionally to create underground chambers for product storage or waste disposal. For more than 50 years, salt caverns have been used to store hydrocarbon products. Recently, concerns over the costs and environmental effects of land disposal and incineration have sparked interest in using salt caverns for waste disposal. Countries using or considering using salt caverns for waste disposal include Canada (oil-production wastes), Mexico (purged sulfates from salt evaporators), Germany (contaminated soils and ashes), the United Kingdom (organic residues), and the Netherlands (brine purification wastes). In the US, industry and the regulatory community are pursuing the use of salt caverns for disposal of oil-field wastes. In 1988, the US Environmental Protection Agency (EPA) issued a regulatory determination exempting wastes generated during oil and gas exploration and production (oil-field wastes) from federal hazardous waste regulations--even though such wastes may contain hazardous constituents. At the same time, EPA urged states to tighten their oil-field waste management regulations. The resulting restrictions have generated industry interest in the use of salt caverns for potentially economical and environmentally safe oil-field waste disposal. Before the practice can be implemented commercially, however, regulators need assurance that disposing of oil-field wastes in salt caverns is technically and legally feasible and that potential health effects associated with the practice are acceptable. In 1996, Argonne National Laboratory (ANL) conducted a preliminary technical and legal evaluation of disposing of nonhazardous oil-field wastes (NOW) into salt caverns. It investigated regulatory issues; the types of oil-field wastes suitable for cavern disposal; cavern design and location considerations; and disposal operations, closure and remediation issues. It determined

  20. Chemical, physical characterization and salinity distribution of the oilfield water in the Upper Sandstone Member of the Zubair reservoir at Rumaila North Oilfield, Southern Iraq

    Directory of Open Access Journals (Sweden)

    Salih Awadh

    2018-01-01

    Full Text Available The oilfield water in the Upper Sandstone Member of the Zubair reservoir (Barriemian-Hauterivian at Rumaila North Oil Field was investigated for the interpretation of salinity and geochemical evolution of brine compositions. The interaction of the oilfield water with reservoir rock resulted in a brine water derived from the marine water origin of partial mixing with meteoric water similar to the compositional ranges of formation water from Gulf of Mexico offshore/onshore Mesozoic reservoirs. The high TDS (207350- 230100; average 215625 mg/L is consistent with the electrical conductivity (340362-372762; average 351024μs, and predominantly represented by Cl (123679 mg/L as anions and (29200 and 14674 mg/L for Na and Ca as cations respectively. The contribution of cation (epm% are as Na (70.2, Ca (18.9, Mg (8.1 and K (1.7; and anion as Cl (99.7, SO4 (0.25, HCO3 (0.07 and CO3 (0.005. sodium (57550-60500mg/L is greater than of seawater six times, calcium and magnesium three times greater, and chloride 6.5 times greater, but Sulfate is depleted to six times less due to a sulfur release from sulphates and link with different hydrocarbon species, precipices as native sulphur and link with hydrogen forming H2S. The Zubair oilfield water is characterised by acidic pH (pH=5.2- 5.77 enhanced petrophysical properties, high specific gravity (1.228 predicts a high fluid pressure (4866 psi, hydrocarbon saturation (0.43%, water saturation (0.57% and porosity (12.7. The Mineral saturation model indicates that the Zubair oilfield water is an unsaturated water with respect to all suggested minerals at 5.45, but at simulated pH, brucite being an equilibrium at pH 9.12, but brucite and portlandite being supersaturated at pH 11.9. The mineral solubility responses to the changes in temperature, pressure, pH, Eh, and ionic strength, thereby formation damage is proportionally developed.

  1. Investigation of Multi-Criteria Decision Consistency: A Triplex Approach to Optimal Oilfield Portfolio Investment Decisions

    Science.gov (United States)

    Qaradaghi, Mohammed

    Complexity of the capital intensive oil and gas portfolio investments is continuously growing. It is manifested in the constant increase in the type, number and degree of risks and uncertainties, which consequently lead to more challenging decision making problems. A typical complex decision making problem in petroleum exploration and production (E&P) is the selection and prioritization of oilfields/projects in a portfolio investment. Prioritizing oilfields maybe required for different purposes, including the achievement of a targeted production and allocation of limited available development resources. These resources cannot be distributed evenly nor can they be allocated based on the oilfield size or production capacity alone since various other factors need to be considered simultaneously. These factors may include subsurface complexity, size of reservoir, plateau production and needed infrastructure in addition to other issues of strategic concern, such as socio-economic, environmental and fiscal policies, particularly when the decision making involves governments or national oil companies. Therefore, it would be imperative to employ decision aiding tools that not only address these factors, but also incorporate the decision makers' preferences clearly and accurately. However, the tools commonly used in project portfolio selection and optimization, including intuitive approaches, vary in their focus and strength in addressing the different criteria involved in such decision problems. They are also disadvantaged by a number of drawbacks, which may include lacking the capacity to address multiple and interrelated criteria, uncertainty and risk, project relationship with regard to value contribution and optimum resource utilization, non-monetary attributes, decision maker's knowledge and expertise, in addition to varying levels of ease of use and other practical and theoretical drawbacks. These drawbacks have motivated researchers to investigate other tools and

  2. A new approach of proration-injection allocation for water-flooding mature oilfields

    Directory of Open Access Journals (Sweden)

    Shuyong Hu

    2015-03-01

    Full Text Available This paper presents a new method of injection-production allocation estimation for water-flooding mature oilfields. The suggested approach is based on logistic growth rate functions and several type-curve matching methods. Using the relationship between these equations, oil production and water injection rate as well as injection-production ratio can be easily forecasted. The calculation procedure developed and outlined in this paper requires very few production data and is easily implemented. Furthermore, an oilfield case has been analyzed. The synthetic and field cases validate the calculation procedure, so it can be accurately used in forecasting production data, and it is important to optimize the whole injection-production system.

  3. Dating of oilfield contamination by Natural Occurring Radioactive Materials (NORM) using isotopic ratios

    International Nuclear Information System (INIS)

    Al-Masri, M. S.; Othman, I.; Aba, A.

    2008-05-01

    In the present work, the possibility of using radium isotope ratios (226, 224, 228) for dating of NORM contaminated sites in the oilfields due to uncontrolled disposal of produced water into the environmental NORM contaminated soil sample were collected from different locations in Syrian Oilfields and radioactivity analysed. In addition, production water samples were collected and analysed to determine the isotopes ratios of the naturally occurring radioactive materials. The results have shown that the 228 Ra/ 226 Ra can be successfully used to date contaminated soil provided that this ratio is determined in production water. Moreover, the 210 Pb/ 226 Ra activity ratios was used for the first time for dating of contaminated soil where all factors affecting the method application have been evaluated. Furthermore, the obtained results for dating using the three methods were compared with the actual contamination dates provided by the oil companies. (Authors)

  4. The performance of electroless nickel deposits in oil-field environments

    International Nuclear Information System (INIS)

    Mack, R.; Bayes, M.

    1984-01-01

    An experimental study was conducted on an electroless nickel plated (represented by Enplate NI-422) C-90 steel, uncoated C-90 steel, AISI 420, 174 PH, SAF 2205, and HASTELLOY /sup R/ G-3 to determine their corrosion-performance in twelve simulated downhole oil or gas production environments during 28 day exposures. These environments were aqueous brines containing various concentrations of Cl - , H 2 S and/or CO 2 , and over a range of temperatures. The results from this study and oilfield data for electroless nickel plated low alloy steels are presented and discussed. The study demonstrates the feasibility of electroless nickel coated low alloy steels as an economical substitute for some highly alloyed materials in certain oilfield applications; the field data support this

  5. Calculation method of water injection forward modeling and inversion process in oilfield water injection network

    Science.gov (United States)

    Liu, Long; Liu, Wei

    2018-04-01

    A forward modeling and inversion algorithm is adopted in order to determine the water injection plan in the oilfield water injection network. The main idea of the algorithm is shown as follows: firstly, the oilfield water injection network is inversely calculated. The pumping station demand flow is calculated. Then, forward modeling calculation is carried out for judging whether all water injection wells meet the requirements of injection allocation or not. If all water injection wells meet the requirements of injection allocation, calculation is stopped, otherwise the demand injection allocation flow rate of certain step size is reduced aiming at water injection wells which do not meet requirements, and next iterative operation is started. It is not necessary to list the algorithm into water injection network system algorithm, which can be realized easily. Iterative method is used, which is suitable for computer programming. Experimental result shows that the algorithm is fast and accurate.

  6. Data Analysis and Neuro-Fuzzy Technique for EOR Screening: Application in Angolan Oilfields

    Directory of Open Access Journals (Sweden)

    Geraldo A. R. Ramos

    2017-06-01

    Full Text Available In this work, a neuro-fuzzy (NF simulation study was conducted in order to screen candidate reservoirs for enhanced oil recovery (EOR projects in Angolan oilfields. First, a knowledge pattern is extracted by combining both the searching potential of fuzzy-logic (FL and the learning capability of neural network (NN to make a priori decisions. The extracted knowledge pattern is validated against rock and fluid data trained from successful EOR projects around the world. Then, data from Block K offshore Angolan oilfields are then mined and analysed using box-plot technique for the investigation of the degree of suitability for EOR projects. The trained and validated model is then tested on the Angolan field data (Block K where EOR application is yet to be fully established. The results from the NF simulation technique applied in this investigation show that polymer, hydrocarbon gas, and combustion are the suitable EOR techniques.

  7. Cracking and thermal maturity of Ordovician oils from Tahe Oilfield, Tarim Basin, NW China

    Directory of Open Access Journals (Sweden)

    Anlai Ma

    2017-12-01

    Full Text Available The thermal maturity of the Ordovician oils from the Tahe oilfield of Tarim Basin, NW China was assessed through various maturity parameters, such as biomarkers, aromatic parameters, and diamondoid parameters. Both Ts/(Ts+Tm and C29Ts/(C29H+C29Ts values indicate that the maturity of oils has not reached the condensates stage, which is consistent with the maturity obtained by MPI1. However, the diamondoid maturity suggests that the oil maturity ranges 1.1%–1.6% Ro, which is apparently higher than that of the maturity obtained by the biomarker and MPI1. This discrepancy in maturity may indicate that the Ordovician reservoir has multiple filling history. The 4-MD+3-MD concentration of oils disperses and increases slowly when the Ts/(Ts+Tm value is lower than 0.55. Meanwhile, the value increases rapidly when the Ts/(Ts+Tm value is higher than 0.55. It is proposed that the diamondoid baseline is about 15 μg/goil for marine oils in the Tahe oilfield based on the diamondoid concentration of marine oils from reservoirs of various age. The concentration of 4-MD+3-MD of most Ordovician oils generally ranges from 4.5 to 35 μg/goil, suggesting that the degree of oil-cracking is lower than 50% and the deep Ordovician have potential of oil exploration. The distribution of the concentration of 4-MD+3-MD is characterized by being high in the east and south, low in the west and north, proposing that the two migration pathways exit in the oilfield, which are from east to west and from south to north, respectively. The migration directions are consistent with the results obtained from the oil density and the maturity parameters such as Ts/(Ts+Tm. Thus, suggesting the concentration of 4-MD+3-MD can be used as migration index in oilfield scale.

  8. Risk assessment of nonhazardous oil-field waste disposal in salt caverns

    International Nuclear Information System (INIS)

    Elcock, D.

    1998-01-01

    In 1996, Argonne National Laboratory (ANL) conducted a preliminary technical and legal evaluation of disposing of nonhazardous oil-field wastes (NOW) into salt caverns. Argonne determined that if caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they could be suitable for disposing of oil-field wastes. On the basis of these findings, Argonne subsequently conducted a preliminary evaluation of the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from the NOW disposed of in domal salt caverns. Steps used in this evaluation included the following: identifying potential contaminants of concern, determining how humans could be exposed to these contaminants, assessing contaminant toxicities, estimating contaminant intakes, and calculating human cancer and noncancer risk estimates. Five postclosure cavern release scenarios were assessed. These were inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks, failure of the cavern through leaky interbeds, and a partial collapse of the cavern roof. Assuming a single, generic, salt cavern and generic oil-field wastes, potential human health effects associated with constituent hazardous substances (arsenic, benzene, cadmium, and chromium) were assessed under each of these scenarios. Preliminary results provided excess cancer risk and hazard index (referring to noncancer health effects) estimates that were well within the US Environmental Protection Agency (EPA) target range for acceptable exposure risk levels. These results led to the preliminary conclusion that from a human health perspective, salt caverns can provide an acceptable disposal method for nonhazardous oil-field wastes

  9. Investigation of nanoeffect on wear of details and ties of oilfield devices

    International Nuclear Information System (INIS)

    Shahbazov, E.G.; Shafiyev, Sh.Sh.

    2010-01-01

    The investigations have been carried out at SOCAR on the study of nanoparticles effect on the corrosion of metallic surfaces. It was defined that corrosion rate decreases as a result.It is stated in the article that nanotechnology applications have prospects for protection of details and ties of oilfield equipment. It is necessary to work out special programs for this case. The authors had an attempt to form the main aspects of such programs.

  10. Risk assessment of nonhazardous oil-field waste disposal in salt caverns.

    Energy Technology Data Exchange (ETDEWEB)

    Elcock, D.

    1998-03-05

    In 1996, Argonne National Laboratory (ANL) conducted a preliminary technical and legal evaluation of disposing of nonhazardous oil-field wastes (NOW) into salt caverns. Argonne determined that if caverns are sited and designed well, operated carefully, closed properly, and monitored routinely, they could be suitable for disposing of oil-field wastes. On the basis of these findings, Argonne subsequently conducted a preliminary evaluation of the possibility that adverse human health effects (carcinogenic and noncarcinogenic) could result from exposure to contaminants released from the NOW disposed of in domal salt caverns. Steps used in this evaluation included the following: identifying potential contaminants of concern, determining how humans could be exposed to these contaminants, assessing contaminant toxicities, estimating contaminant intakes, and calculating human cancer and noncancer risk estimates. Five postclosure cavern release scenarios were assessed. These were inadvertent cavern intrusion, failure of the cavern seal, failure of the cavern through cracks, failure of the cavern through leaky interbeds, and a partial collapse of the cavern roof. Assuming a single, generic, salt cavern and generic oil-field wastes, potential human health effects associated with constituent hazardous substances (arsenic, benzene, cadmium, and chromium) were assessed under each of these scenarios. Preliminary results provided excess cancer risk and hazard index (referring to noncancer health effects) estimates that were well within the US Environmental Protection Agency (EPA) target range for acceptable exposure risk levels. These results led to the preliminary conclusion that from a human health perspective, salt caverns can provide an acceptable disposal method for nonhazardous oil-field wastes.

  11. Chloride ion transport and fate in oilfield wastewater reuse by interval dynamic multimedia aquivalence model.

    Science.gov (United States)

    Hu, Y; Zhang, C; Wang, D Z; Wen, J Y; Chen, M H; Li, Y

    2013-01-01

    A surface flow constructed wetland was built up to dispose of oilfield wastewater with a high level of inorganic salt ions. Chlorine ion (Cl(-)) was selected as an indicator of soil secondary salinization, and an interval dynamic multimedia aquivalence (IDMA) model was developed to investigate the dynamic multimedia environmental (air, water, soil, flora, and groundwater) effects of Cl(-) in the wastewater irrigation process between 2002 and 2020. The modeled Cl(-) concentrations were in good agreement with the measured ones, as indicated by the interval average logarithmic residual errors (IALREs) being generally lower than 0.5 logarithmic units. The model results showed that the temporal trends of Cl(-) concentrations in the multimedia environments represented a relatively steady state. More than 97.00% of the mass exchange was finished between soil and groundwater compartments, and Cl(-) finally outputted the environmental system by the pathways of advection outflows in the water (71.03%) and groundwater (24.02%). Soil (59.17%) was the dominant sink of Cl(-). It was revealed that the high level of Cl(-) in oilfield wastewater was well treated by the constructed wetland, and there was not a significant environmental effect of soil secondary salinization in the oilfield wastewater reused for the constructed wetland irrigation.

  12. Polycyclic Aromatic Hydrocarbons in the Dagang Oilfield (China: Distribution, Sources, and Risk Assessment

    Directory of Open Access Journals (Sweden)

    Haihua Jiao

    2015-05-01

    Full Text Available The levels of 16 polycyclic aromatic hydrocarbons (PAHs were investigated in 27 upper layer (0–25 cm soil samples collected from the Dagang Oilfield (China in April 2013 to estimate their distribution, possible sources, and potential risks posed. The total concentrations of PAHs (∑PAHs varied between 103.6 µg·kg−1 and 5872 µg·kg−1, with a mean concentration of 919.8 µg·kg−1; increased concentrations were noted along a gradient from arable desert soil (mean 343.5 µg·kg−1, to oil well areas (mean of 627.3 µg·kg−1, to urban and residential zones (mean of 1856 µg·kg−1. Diagnostic ratios showed diverse source of PAHs, including petroleum, liquid fossil fuels, and biomass combustion sources. Combustion sources were most significant for PAHs in arable desert soils and residential zones, while petroleum sources were a significant source of PAHs in oilfield areas. Based ontheir carcinogenity, PAHs were classified as carcinogenic (B or not classified/non-carcinogenic (NB. The total concentrations of carcinogenic PAHs (∑BPAHs varied from 13.3 µg·kg−1 to 4397 µg·kg−1 across all samples, with a mean concentration of 594.4 µg·kg−1. The results suggest that oilfield soil is subject to a certain level of ecological environment risk.

  13. Estimate of Hot Dry Rock Geothermal Resource in Daqing Oilfield, Northeast China

    Directory of Open Access Journals (Sweden)

    Guangzheng Jiang

    2016-10-01

    Full Text Available Development and utilization of deep geothermal resources, especially a hot dry rock (HDR geothermal resource, is beneficial for both economic and environmental consideration in oilfields. This study used data from multiple sources to assess the geothermal energy resource in the Daqing Oilfield. The temperature logs in boreholes (both shallow water wells and deep boreholes and the drilling stem test temperature were used to create isothermal maps in depths. Upon the temperature field and thermophysical parameters of strata, the heat content was calculated by 1 km × 1 km × 0.1 km cells. The result shows that in the southeastern part of Daqing Oilfield, the temperature can reach 150 °C at a depth of 3 km. The heat content within 3–5 km is 24.28 × 1021 J, wherein 68.2% exceeded 150 °C. If the recovery factor was given by 2% and the lower limit of temperature was set to be 150 °C, the most conservative estimate for recoverable HDR geothermal resource was 0.33 × 1021 J. The uncertainties of the estimation are mainly contributed to by the temperature extrapolation and the physical parameter selections.

  14. Mex Bay

    African Journals Online (AJOL)

    user

    2015-02-23

    Feb 23, 2015 ... surveys to assess the vulnerability of the most important physical and eutrophication parameters along. El- Mex Bay coast. As a result of increasing population and industrial development, poorly untreated industrial waste, domestic sewage, shipping industry and agricultural runoff are being released to the.

  15. Detailed study of seismic wave attenuation from four oilfields in Abu Dhabi, United Arab Emirates

    Science.gov (United States)

    Bouchaala, F.; Ali, M. Y.; Matsushima, J.

    2018-02-01

    In the present study, we provide a detailed study of seismic wave attenuation obtained from four oilfields. The reservoir zones of these oilfields are complicated due to complex fracture networks, the presence of tar mat and high heterogeneity of carbonate rocks of which the subsurface of Abu Dhabi is mainly composed. These complexities decrease signal-to-noise ratio and make attenuation estimation difficult. We obtained high-resolution attenuation profiles from vertical seismic profiling (VSP) and sonic waveform data. The VSP data were recorded in all four oilfields and the sonic data were acquired in the reservoir zones of oilfields I and IV. We found that the VSP scattering attenuation ({Q}{{S}{{c}}{{a}}{{t}}}-1) varies from -0.080 to 0.180 over a depth range of 400-3500 m. We attributed this significant scattering to the high heterogeneity of carbonate rocks. The scattering profiles seem to be sensitive to fractures, lithology heterogeneity and tar mat, but their effect is superimposed. The VSP intrinsic attenuation varies from -0.15 to 0.246 with high variation within each formation. Since intrinsic attenuation is closely related to fluids, we assumed that this variation is due to the non-uniform distribution of fluids caused by the complex porosity network of the subsurface. The sonic monopole attenuation ({Q}{{M}{{f}}}-1) in the reservoir zones ranges between 0.033-0.094 and dipole inline attenuation ({Q}{{I}{{n}}{{l}}}-1) ranges from 0.040-0.138. The sonic attenuation appears to be sensitive to the presence of fluid and type of fractures, where it shows high attenuation for open fractures and low attenuation for resistive fractures. The zones with high clay content display high sonic intrinsic attenuation in the reservoir of oilfield II. We explain this by the frictional movement between the clay and carbonates due to the elasticity contrast of these two materials. Therefore, the solid grain friction may be the dominant attenuation mechanism in those zones.

  16. Deep-water oilfield development cost analysis and forecasting —— Take gulf of mexico for example

    Science.gov (United States)

    Shi, Mingyu; Wang, Jianjun; Yi, Chenggao; Bai, Jianhui; Wang, Jing

    2017-11-01

    Gulf of Mexico (GoM) is the earliest offshore oilfield which has ever been developed. It tends to breed increasingly value of efficient, secure and cheap key technology of deep-water development. Thus, the analyze of development expenditure in this area is significantly important the evaluation concept of deep-water oilfield all over the world. This article emphasizes on deep-water development concept and EPC contract value in GoM in recent 10 years in case of comparison and selection to the economic efficiency. Besides, the QUETOR has been put into use in this research processes the largest upstream cost database to simulate and calculate the calculating examples’ expenditure. By analyzing and forecasting the deep-water oilfield development expenditure, this article explores the relevance between expenditure index and oil price.

  17. Study on fine geological modelling of the fluvial sandstone reservoir in Daqing oilfield

    Energy Technology Data Exchange (ETDEWEB)

    Zhoa Han-Qing [Daqing Research Institute, Helongjiang (China)

    1997-08-01

    These paper aims at developing a method for fine reservoir description in maturing oilfields by using close spaced well logging data. The main productive reservoirs in Daqing oilfield is a set of large fluvial-deltaic deposits in the Songliao Lake Basin, characterized by multi-layers and serious heterogeneities. Various fluvial channel sandstone reservoirs cover a fairly important proportion of reserves. After a long period of water flooding, most of them have turned into high water cut layers, but there are considerable residual reserves within them, which are difficult to find and tap. Making fine reservoir description and developing sound a geological model is essential for tapping residual oil and enhancing oil recovery. The principal reason for relative lower precision of predicting model developed by using geostatistics is incomplete recognition of complex distribution of fluvial reservoirs and their internal architecture`s. Tasking advantage of limited outcrop data from other regions (suppose no outcrop data available in oilfield) can only provide the knowledge of subtle changing of reservoir parameters and internal architecture. For the specific geometry distribution and internal architecture of subsurface reservoirs (such as in produced regions) can be gained only from continuous infilling logging well data available from studied areas. For developing a geological model, we think the first important thing is to characterize sandbodies geometries and their general architecture`s, which are the framework of models, and then the slight changing of interwell parameters and internal architecture`s, which are the contents and cells of the model. An excellent model should possess both of them, but the geometry is the key to model, because it controls the contents and cells distribution within a model.

  18. Conference delegate package of the oilfield transportation conference and trade show: steering the industry into the future

    International Nuclear Information System (INIS)

    Anon.

    1997-01-01

    The transportation component of the petroleum service industry was the focus of this conference. The human factors that play a role in oilfield trucking accidents were discussed. The industry has set standards and has taken the initiative to establish training programs in which basic criteria for transporting dangerous goods will be met. The principal themes addressed by the conference included an overall approach to industry compliance, new technologies, minimum safety requirements, forming partnerships with the Workers' Compensation Board, drug and alcohol policies and testing, oilfield driver training program, and risk management of human capital

  19. The analysis of scaling mechanism for water-injection pipe columns in the Daqing Oilfield

    OpenAIRE

    Jing, Guolin; Tang, Shan; Li, Xiaoxiao; Wang, Huaiyuan

    2013-01-01

    Although water-injection in mature reservoirs is a promising low-cost method of enhanced oil recovery (EOR), in the process of development in the oilfield, scale has been produced in water-injection pipe columns. The ability to prevent and control the deposition of scale is critical to the efficient recovery of crude oil from hard environments, as part of the broader discipline of “flow assurance” in the petroleum industry. To this end laboratory-scale deposition tests have been useful to und...

  20. Treatment of oilfield produced water by anaerobic process coupled with micro-electrolysis.

    Science.gov (United States)

    Li, Gang; Guo, Shuhai; Li, Fengmei

    2010-01-01

    Treatment of oilfield produced water was investigated using an anaerobic process coupled with micro-electrolysis (ME), focusing on changes in chemical oxygen demand (COD) and biodegradability. Results showed that COD exhibited an abnormal change in the single anaerobic system in which it increased within the first 168 hr, but then decreased to 222 mg/L after 360 hr. The biological oxygen demand (five-day) (BODs)/COD ratio of the water increased from 0.05 to 0.15. Hydrocarbons in the wastewater, such as pectin, degraded to small molecules during the hydrolytic acidification process. Comparatively, the effect of ME was also investigated. The COD underwent a slight decrease and the BOD5/COD ratio of the water improved from 0.05 to 0.17 after ME. Removal of COD was 38.3% under the idealized ME conditions (pH 6.0), using iron and active carbon (80 and 40 g/L, respectively). Coupling the anaerobic process with ME accelerated the COD removal ratio (average removal was 53.3%). Gas chromatography/mass spectrometry was used to analyze organic species conversion. This integrated system appeared to be a useful option for the treatment of water produced in oilfields.

  1. Adventure travel: oilfield trucking makes highway rigs look tame and light

    Energy Technology Data Exchange (ETDEWEB)

    Collison, M.

    2000-05-01

    Oilfield trucking as a specialty, involving high stakes in property and health, are discussed. Each rig costs close to one million dollars and operating them, under the watchful eye of GPS satellite or guided by two-way radios, or cellular phones, is a specialty that comes from many years of experience, a Class I licence, special training in first aid, handling dangerous goods and workplace hazardous materials, and readiness to work in mud, slush, and sleet, navigating soft and uneven ground with unwieldy gear and high load ready to tip at any moment. The risks and challenges become even more extreme when the trucker is moving oilfield equipment internationally, where severe climatic conditions, sandstorms, extreme heat and a generally hostile environment, may be augmented by unfamiliar bureaucratic procedures, business practices, and attacks by marauding armed rebel groups. International moves involve internationally recognized shipping terms that define risk and liability between buyer and seller, ocean-safe packaging and complex inventory management. That, of course, is all additional to the trade regulations, import permits, licenses, documentation requirements and insurance procedures of each of the countries traversed during the move.

  2. Application of oil-field well log interpretation techniques to the Cerro Prieto Geothermal Field

    Energy Technology Data Exchange (ETDEWEB)

    Ershaghi, I.; Phillips, L.B.; Dougherty, E.L.; Handy, L.L.

    1979-10-01

    An example is presented of the application of oil-field techniques to the Cerro Prieto Field, Mexico. The lithology in this field (sand-shale lithology) is relatively similar to oil-field systems. The study was undertaken as a part of the first series of case studies supported by the Geothermal Log Interpretation Program (GLIP) of the US Department of Energy. The suites of logs for individual wells were far from complete. This was partly because of adverse borehole conditions but mostly because of unavailability of high-temperature tools. The most complete set of logs was a combination of Dual Induction Laterolog, Compensated Formation Density Gamma Ray, Compensated Neutron Log, and Saraband. Temperature data about the wells were sketchy, and the logs had been run under pre-cooled mud condition. A system of interpretation consisting of a combination of graphic and numerical studies was used to study the logs. From graphical studies, evidence of hydrothermal alteration may be established from the trend analysis of SP (self potential) and ILD (deep induction log). Furthermore, the cross plot techniques using data from density and neutron logs may help in establishing compaction as well as rock density profile with depth. In the numerical method, R/sub wa/ values from three different resistivity logs were computed and brought into agreement. From this approach, values of formation temperature and mud filtrate resistivity effective at the time of logging were established.

  3. Non-Newtonian Flow Characteristics of Heavy Oil in the Bohai Bay Oilfield: Experimental and Simulation Studies

    Directory of Open Access Journals (Sweden)

    Xiankang Xin

    2017-10-01

    Full Text Available In this paper, physical experiments and numerical simulations were applied to systematically investigate the non-Newtonian flow characteristics of heavy oil in porous media. Rheological experiments were carried out to determine the rheology of heavy oil. Threshold pressure gradient (TPG measurement experiments performed by a new micro-flow method and flow experiments were conducted to study the effect of viscosity, permeability and mobility on the flow characteristics of heavy oil. An in-house developed novel simulator considering the non-Newtonian flow was designed based on the experimental investigations. The results from the physical experiments indicated that heavy oil was a Bingham fluid with non-Newtonian flow characteristics, and its viscosity-temperature relationship conformed to the Arrhenius equation. Its viscosity decreased with an increase in temperature and a decrease in asphaltene content. The TPG measurement experiments was impacted by the flow rate, and its critical flow rate was 0.003 mL/min. The TPG decreased as the viscosity decreased or the permeability increased and had a power-law relationship with mobility. In addition, the critical viscosity had a range of 42–54 mPa∙s, above which the TPG existed for a given permeability. The validation of the designed simulator was positive and acceptable when compared to the simulation results run in ECLIPSE V2013.1 and Computer Modelling Group (CMG V2012 software as well as when compared to the results obtained during physical experiments. The difference between 0.0005 and 0.0750 MPa/m in the TPG showed a decrease of 11.55% in the oil recovery based on the simulation results, which demonstrated the largely adverse impact the TPG had on heavy oil production.

  4. Effects of produced waters at oilfield production sites on the Osage Indian Reservation, northeastern Oklahoma

    Science.gov (United States)

    Otton, James K.; Asher-Bolinder, Sigrid; Owen, Douglass E.; Hall, Laurel

    1997-01-01

    The authors conducted limited site surveys in the Wildhorse and Burbank oilfields on the Osage Indian Reservation, northeastern Oklahoma. The purpose was to document salt scarring, erosion, and soil and water salinization, to survey for radioactivity in oilfield equipment, and to determine if trace elements and naturally occurring radioactive materials (NORM) were present in soils affected by oilfield solid waste and produced waters. These surveys were also designed to see if field gamma spectrometry and field soil conductivity measurements were useful in screening for NORM contamination and soil salinity at these sites. Visits to oilfield production sites in the Wildhorse field in June of 1995 and 1996 confirmed the presence of substantial salt scarring, soil salinization, and slight to locally severe erosion. Levels of radioactivity on some oil field equipment, soils, and road surfaces exceed proposed state standards. Radium activities in soils affected by tank sludge and produced waters also locally exceed proposed state standards. Laboratory analyses of samples from two sites show moderate levels of copper, lead, and zinc in brine-affected soils and pipe scale. Several sites showed detectable levels of bromine and iodine, suggesting that these trace elements may be present in sufficient quantity to inhibit plant growth. Surface waters in streams at two sampled sites exceed total dissolved solid limits for drinking waters. At one site in the Wildhorse field, an EM survey showed that saline soils in the upper 6m extend from a surface salt scar downvalley about 150 m. (Photo [95k]: Dead oak trees and partly revegetated salt scar at Site OS95-2 in the Wildhorse field, Osage County, Oklahoma.) In the Burbank field, limited salt scarring and slight erosion occurs in soils at some sites and low to moderate levels of radioactivity were observed in oil field equipment at some sites. The levels of radioactivity and radium observed in some soils and equipment at these

  5. The Search for Fluid Injection-induced Seismicity in California Oilfields

    Science.gov (United States)

    Layland-Bachmann, C. E.; Brodsky, E. E.; Foxall, W.; Goebel, T.; Jordan, P. D.

    2017-12-01

    During recent years, earthquakes associated with human activity have become a matter of heightened public concern. Wastewater injection is a major concern, as seismic events with magnitudes larger than M5.5 have been linked to this practice. Much of the research in the United States is focused on the mid-continental regions, where low rates of naturally-occurring seismicity and high-volume injection activities facilitate easier identification by statistical correlation of potentially induced seismic events . However, available industry data are often limited in these regions and therefore limits our ability to connect specific human activities to earthquakes. Specifically, many previous studies have focused primarily on injection activity in single wells, ignoring the interconnectivity of production and injection in a reservoir. The situation in California differs from the central U.S. in two ways: (1) A rich dataset of oilfield activity is publically available from state agencies, which enables a more in-depth investigation of the human forcing; and (2) the identification of potential anthropogenically-induced earthquakes is complex as a result of high tectonic activity. Here we address both differences. We utilize a public database of hydrologically connected reservoirs to assess whether there are any statistically significant correlations between the net injected volumes, reservoir pressures and injection depths, and the earthquake locations and frequencies of occurrence. We introduce a framework of physical and empirical models and statistical techniques to identify potentially induced seismic events. While the aim is to apply the methods statewide, we first apply our methods in the Southern San Joaquin Valley. Although, we find an anomalously high earthquake rate in Southern Kern County oilfields, which is consistent with previous studies, we do not find a simple straightforward correlation. To successfully study induced seismicity we need a seismic catalog

  6. Ecological effects of low toxicity oil-based mud drilling in the Beatrice oilfield

    Energy Technology Data Exchange (ETDEWEB)

    Addy, J M; Hartley, J P; Tibbetts, P J.C.

    1984-12-01

    To investigate the effects of drilling discharges on the seabed fauna, surveys were carried out in the Beatrice oilfield after drilling 13 wells with water-based muds, and then after one and five further wells had been drilled using low toxicity oil-based muds. Localized benthic effects were found after the water-based mud drilling. After the use of oil-based muds, the nature of the effects was different, although there was little increase in the area involved. Possible reasons for this are discussed and burial and organic enrichment are suggested as the major influences. It is concluded that the use of low toxicity oil-based mud at Beatrice has resulted in only limited benthic effects, suggesting that the use of these muds is environmentally acceptable.

  7. Research on high speed drilling technology and economic integration evaluation in Oilfield

    Science.gov (United States)

    Wang, Kun; Ni, Hongjian; Cheng, Na; Song, Jingbo

    2018-01-01

    The carbonate reservoir in the oilfield mainly formed in Ordovician System and Carboniferous System. The geology here is very complicated, with high heterogeneity. It gets much more difficult to control the well deflection in Permian system so that high accident ratio could be expected. The buried depth of the reservoir is large, normally 4600-6600m deep. The temperature of the layer is higher than 132 and the pressure is greater than 62MPa. The reservoir is with a high fluid properties, mainly including thin oil, heavy oil, condensate oil, gas and so on; the ground is very hard to drill, so we can foresee low drilling speed, long drilling period and high drilling cost, which will surely restrict the employing progress of the reservoir.

  8. A new chlorine logging tool: Application in the oilfield development with high salinity formation water

    International Nuclear Information System (INIS)

    Qing-Yuan, He; Xin-Miao, Hu; Geng-Fei, Wu; Wen-DA, J.

    1997-01-01

    Radiating formations with isotopes neutron source (Am-Be), and using chlorine element contained in the formation water as a tracer indicator, the chlorine spectrum well logging tool has been regarded as the important and useful tool in the determination of water flooding intensity of formation intervals, especially in the oilfield development stages with high salinity formation water. However, the accuracy of determination of the oil/water-bearings needs to be improved. A new chlorine spectrum logging tool with two detectors has been developed. The short (near) detector uses a He-3 counter tube to measure formation epithermal neutron intensity, the long (far) detector uses a BGO crystal detector to replace traditional Nal detector for measuring the captured X gamma ray spectrum produced by the thermal neutron capture process in the formation. Although the energy resolution of BGO detector to gamma rays is less effective than that of Nal detector, the efficiency of BGO detector to high energy gamma rays is much better. This advantage helps to detect captured chlorine gamma rays, which increases the ability of chlorine element detection. The effect of statistical errors is also reduced. The spectrum autostabilization function in the downhole tool improves the reliability of the whole system. The new chlorine spectrum logging tool can give three log curves simultaneously, these curves are formation porosity, chlorine content, and the ratio of chlorine content and thermal neutron intensity. When formation porosity is larger than 10 p.u, formation water salinity is greater than 40,000 ppm, the resolution to the oil/water-bearings is increased to about 10% compared with the old version tool. Field tests show that the accuracy of water flooding intensity evaluation has been upgraded considerably with the use of new chlorine spectrum logging tool, which contributes greatly to the oilfield development with high salinity formation water

  9. A new chlorine logging tool: Application in the oilfield development with high salinity formation water

    Energy Technology Data Exchange (ETDEWEB)

    Qing-Yuan, He; Xin-Miao, Hu; Geng-Fei, Wu [China National Petroleum Corp. (China). Jianghan Well Logging Institute; Wen-DA, J. [China National Petroleum Corp. (China). Development Bureau

    1997-10-01

    Radiating formations with isotopes neutron source (Am-Be), and using chlorine element contained in the formation water as a tracer indicator, the chlorine spectrum well logging tool has been regarded as the important and useful tool in the determination of water flooding intensity of formation intervals, especially in the oilfield development stages with high salinity formation water. However, the accuracy of determination of the oil/water-bearings needs to be improved. A new chlorine spectrum logging tool with two detectors has been developed. The short (near) detector uses a He-3 counter tube to measure formation epithermal neutron intensity, the long (far) detector uses a BGO crystal detector to replace traditional Nal detector for measuring the captured X gamma ray spectrum produced by the thermal neutron capture process in the formation. Although the energy resolution of BGO detector to gamma rays is less effective than that of Nal detector, the efficiency of BGO detector to high energy gamma rays is much better. This advantage helps to detect captured chlorine gamma rays, which increases the ability of chlorine element detection. The effect of statistical errors is also reduced. The spectrum autostabilization function in the downhole tool improves the reliability of the whole system. The new chlorine spectrum logging tool can give three log curves simultaneously, these curves are formation porosity, chlorine content, and the ratio of chlorine content and thermal neutron intensity. When formation porosity is larger than 10 p.u, formation water salinity is greater than 40,000 ppm, the resolution to the oil/water-bearings is increased to about 10% compared with the old version tool. Field tests show that the accuracy of water flooding intensity evaluation has been upgraded considerably with the use of new chlorine spectrum logging tool, which contributes greatly to the oilfield development with high salinity formation water 4 refs., 2 tabs., 7 figs.

  10. Effects of untreated and treated oilfield-produced water on seed germination, seedling development, and biomass production of sunflower (Helianthus annuus L.).

    Science.gov (United States)

    da Costa Marques, Mônica Regina; de Souza, Paulo Sérgio Alves; Rigo, Michelle Machado; Cerqueira, Alexandre Andrade; de Paiva, Julieta L; Merçon, Fábio; Perez, Daniel Vidal

    2015-10-01

    This study aims to evaluate possible toxic effects of oil and other contaminants from oilfield-produced water from oil exploration and production, on seed germination, and seedling development of sunflower (Helianthus annuus L.). In comparison, as treated by electroflocculation, oilfield-produced water, with lower oil and organic matter content, was also used. Electroflocculation treatment of oilfield-produced water achieved significant removals of chemical oxygen demand (COD) (94 %), oil and grease (O&G) (96 %), color (97 %), and turbidity (99 %). Different O&G, COD, and salt levels of untreated and treated oilfield-produced water did not influence germination process and seedling biomass production. Normal seedlings percentage and vigor tended to decrease more intensely in O&G and COD levels, higher than 337.5 mg L(-1) and 1321 mg O2 L(-1), respectively, using untreated oilfield-produced water. These results indicate that this industrial effluent must be treated, in order to not affect adversely seedling development. This way, electroflocculation treatment appears as an interesting alternative to removing oil and soluble organic matter in excess from oilfield-produced water improving sunflower's seedling development and providing a friendly environmental destination for this wastewater, reducing its potential to harm water resources, soil, and biota.

  11. Urban Greening Bay Area

    Science.gov (United States)

    Information about the San Francisco Bay Water Quality Project (SFBWQP) Urban Greening Bay Area, a large-scale effort to re-envision urban landscapes to include green infrastructure (GI) making communities more livable and reducing stormwater runoff.

  12. Monitoring Oilfield Operations and GHG Emissions Sources Using Object-based Image Analysis of High Resolution Spatial Imagery

    Science.gov (United States)

    Englander, J. G.; Brodrick, P. G.; Brandt, A. R.

    2015-12-01

    Fugitive emissions from oil and gas extraction have become a greater concern with the recent increases in development of shale hydrocarbon resources. There are significant gaps in the tools and research used to estimate fugitive emissions from oil and gas extraction. Two approaches exist for quantifying these emissions: atmospheric (or 'top down') studies, which measure methane fluxes remotely, or inventory-based ('bottom up') studies, which aggregate leakage rates on an equipment-specific basis. Bottom-up studies require counting or estimating how many devices might be leaking (called an 'activity count'), as well as how much each device might leak on average (an 'emissions factor'). In a real-world inventory, there is uncertainty in both activity counts and emissions factors. Even at the well level there are significant disagreements in data reporting. For example, some prior studies noted a ~5x difference in the number of reported well completions in the United States between EPA and private data sources. The purpose of this work is to address activity count uncertainty by using machine learning algorithms to classify oilfield surface facilities using high-resolution spatial imagery. This method can help estimate venting and fugitive emissions sources from regions where reporting of oilfield equipment is incomplete or non-existent. This work will utilize high resolution satellite imagery to count well pads in the Bakken oil field of North Dakota. This initial study examines an area of ~2,000 km2 with ~1000 well pads. We compare different machine learning classification techniques, and explore the impact of training set size, input variables, and image segmentation settings to develop efficient and robust techniques identifying well pads. We discuss the tradeoffs inherent to different classification algorithms, and determine the optimal algorithms for oilfield feature detection. In the future, the results of this work will be leveraged to be provide activity

  13. FORECASTING THE PERFORMANCE OF AN OIL FIELD, COMPARISON OF VARIOUS USED METHODS: THE CASE OF SHUANGHE OILFIELD, CHINA

    Directory of Open Access Journals (Sweden)

    Theoneste Nzayisenga

    2014-01-01

    Full Text Available While being the dominant source of energy, oil has also brought affluence and power to different societies. Energy produced from oil is fundamental to all parts of society. In the foreseeable future, the majority of energy will still come from oil production. Consequently, reliable methods for forecasting that production are crucial. Petroleum engineers have searched for simple but reliable way to predict oil production for a long time. Many methods have been developed in the latest decades and one common practice is decline curve analysis. Prediction of future production of petroleum wells is important for cost-effective operations of the petroleum industry. This work presents a comparative analysis of methods used to predict the performance of Shuanghe oilfield, China. Using decline curve analysis including three different methods: Arps empirical methods, LL-model and simplified model and the new simplified model, LL-Model, to crosscheck Arps exponential decline model prediction results. The results showed by the comparative analysis of predictions calculated proved LL-model to be the best predictor for Shuanghe oilfield since it takes into account more parameters than the old models used in this work. However, the subsurface information or parameters of the reservoir used in LL-model may not be available every time, therefore Arps models may apply as defined. In Shuanghe oilfield calculated average geological reserves N was estimated at 9449.41 ×104 tons, the average recoverable reserves NR were estimated to 4274.61×104 tons while the water cut was 97% and the water cut predicted by LL-model was 96.7%; not far from water flooding curves value. The exponential decline model showed recoverable reserves NR estimated around 4685.88×104 tons of oil while the decline phase of total development was estimated around 34 years which means that if the actual production conditions remain unchanged, Shuanghe oilfield would continue producing for

  14. [Association between 5-hydroxytryptamine 2A receptor gene polymorphisms and susceptibility to occupational stress in oilfield workers].

    Science.gov (United States)

    Jiang, Y; Palizhati, Abudoureyimu; Gao, X Y; Guan, S Z; Liu, J W

    2016-10-20

    Objective: To investigate the association between 5-hydroxytryptamine 2A (5-HT2A) receptor gene polymorphisms and occupational stress in oilfield workers. Methods: Cluster sampling was used to select 826 oilfield workers from January to August, 2013. The SNaPshot single nucleotide polymorphism (SNP) genotyping method was used to determine the genotypes of rs6313, rs1923884, and rs2070040 in 5-HT2A receptor gene, and the Occupational Stress Inventory-Revised Edition was used to analyze occupational stress in these workers. Results: There were no significant differences in occupational stress between groups with different individual characteristics ( P >0.05 ) . As for the comparison of occupational stress scores between workers with different genotypes of each SNP of 5-HT2A receptor gene, the workers with CC and CT genotypes of rs6313 had significantly higher role boundary scores than those with TT genotype ( P stress score than those with CT genotype ( P occupational role score than those with CC genotype ( P stress score than those with AA genotype ( P occupational stress ( OR =1.56, 95% CI 1.10~2.20) . Conclusion: CT genotype of rs1923884 in 5-HT2A receptor gene may be associated with the susceptibility to occupational stress in oilfield workers.

  15. Terrestrial exposure of oilfield flowline additives diminish soil structural stability and remediative microbial function

    International Nuclear Information System (INIS)

    George, S.J.; Sherbone, J.; Hinz, C.; Tibbett, M.

    2011-01-01

    Onshore oil production pipelines are major installations in the petroleum industry, stretching many thousands of kilometres worldwide which also contain flowline additives. The current study focuses on the effect of the flowline additives on soil physico-chemical and biological properties and quantified the impact using resilience and resistance indices. Our findings are the first to highlight deleterious effect of flowline additives by altering some fundamental soil properties, including a complete loss of structural integrity of the impacted soil and a reduced capacity to degrade hydrocarbons mainly due to: (i) phosphonate salts (in scale inhibitor) prevented accumulation of scale in pipelines but also disrupted soil physical structure; (ii) glutaraldehyde (in biocides) which repressed microbial activity in the pipeline and reduced hydrocarbon degradation in soil upon environmental exposure; (iii) the combinatory effects of these two chemicals synergistically caused severe soil structural collapse and disruption of microbial degradation of petroleum hydrocarbons. - Highlights: → Effects of flowline additives on soil structure and microbial function highlighted. → Phosphonate salts (in scale inhibitor) were found to disrupt soil physical structure. → Glutaraldehyde (in biocides) caused significant reduction of hydrocarbon degradation in soil. → Flowline additive chemicals synergistically affects soil structure and remediative microbial function. - Scale inhibitor and biocide oilfield flowline additives interactively affect soil physical and microbial properties

  16. Waste drilling-fluid-utilising microorganisms in a tropical mangrove swamp oilfield location

    International Nuclear Information System (INIS)

    Benka-Coker, M.O.; Olumagin, A.

    1995-01-01

    Waste drilling-fluid-utilising microorganisms were isolated from drilling-mud cuttings, soil and creek water from a mangrove swamp oilfield location in the Delta area of Nigeria using waste drilling-fluid as the substrate. Eighteen bacterial isolates obtained were identified as species of Staphylococcus, Acinetobacter, Alcaligenes, Serratia, Clostridium, Enterobacter, Klebsiella, Nocardia, Bacillus, Actinomyces, Micrococcus and Pseudomonas, while the genera of fungi isolated were Penicillium, Cladosporium and Fusarium. Even though drilling-fluid-utilising genera were in higher numbers in the soil than in the two other sources examined, the percentages of the total heterotrophic bacteria that utilised waste drilling-fluid were 6.02 in the drilling-mud cuttings, 0.83 in creek water and 0.42 in soil. The screen tests for biodegradation potential of the bacterial isolates showed that, even though all the isolates were able to degrade and utilise the waste fluid for growth, species of Alcaligenes and Micrococcus were more active degraders of the waste. The significance of the results in environmental management in oil-producing areas of Nigeria is discussed. (Author)

  17. Depositional history of the reservoir sandstones, Akpor and Apara oilfields, eastern Niger Delta, Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Amajor, L.C.; Agbaire, D.W. (Port Harcourt Univ. (NG). Dept. of Geology)

    1989-10-01

    A subsurface study of the Agbada Formation in the Akpor and Apara oilfields in the eastern Niger Delta was undertaken in order to determine the depositional development of the reservoir sand-bodies. The study area comprises a maximum of 29 relatively thick sandstones, cyclically interbedded with shales of varying thicknesses. The lowest two sand units, separated by a shale unit and located near the base, produce petroleum from ten wells in both fields. Each sand-body exhibits a coarsening-upward textural gradient. The lower sand-body which is oval-shaped, moderately- to poorly-sorted, fine- to very coarse-grained, carbonaceous, with clay and lignite horizons, is interpreted as a deltaic sand. The unit appears to have migrated landwards, probably as a result of localized transgression, and developed maximum thickness between the two fields. The upper sand is fine-to-pebbly in grain size, well-sorted and glauconitic. Maximum development occurred slightly east of the delta. As the unit prograded in a predominantly southerly direction, genetic currents simultaneously caused it to be channelized. This sand-body is interpreted as an offshore marine bar. The intervening carbonaceous shale is thought to be of lagoonal origin. The pinch-out edges of these sand bodies may constitute prolific stratigraphic traps. (author).

  18. Evaluation of membranes for the treatment of oilfield-produced water

    Directory of Open Access Journals (Sweden)

    Silvio Edegar Weschenfelder

    2015-04-01

    Full Text Available Large quantities of water are generated during oil extraction. Reinjection of this effluent is frequently the most suitable option for environmental considerations. For this purpose, the water produced must have characteristics that will prevent the plugging of the reservoir rocks, i.e., suspended solids and oil and grease content must be lower than 5 mg L-1. This work evaluated the performance of membranes for water treatment, based upon long-term experiments with real effluent, evaluating the permeate flux over time and the effluent characteristics. The results indicated that it is possible to obtain a permeate flux with suspended solids content with less than 1 mg L-1 oil and a grease concentration in the range of 1 to 3 mg L-1 using membranes with a pore size of 0,1 m. After 50 hours of permeation, the permeate fluxes obtained with the polymeric and ceramic membranes were equal to 50 and 300 L h-1 m-2, respectively. With a chemical regeneration procedure, it was possible to recover 95% of the ceramic membrane’s original permeability and 30% of the polymeric membrane’s permeability. Considering the permeate quality, the regeneration efficiency of the membrane and the fluxes achieved, it is possible to point out the use of ceramic membranes as a potential technology for treating oilfield-produced water, and it has the advantage of being a compact and robust process.

  19. Geological implications of radium and helium in oil-field brines: observations, inferences and speculations

    International Nuclear Information System (INIS)

    Lerche, I.

    1993-01-01

    The 1600 yr half-life of radium restricts the time and thus the distance over which radium can migrate in sediments. The dominant source of unsupported radium in sandstone reservoir brines must then be close by and is likely in shales adjacent to the oil-field reservoirs. The chemical similarity of calcium and radium can be used to argue for a local shale-source contribution to the calcium in reservoir sands -suggesting the probability of calcite cementation early in the sedimentary sequence. Helium production by radium decay increases with time. Concentrations of helium found in reservoir oil field brines are then used to suggest that: (a) such reservoirs are dominantly closed systems over geological times; (b) neither methane nor helium in the reservoirs have migrated any significant distance; and (c) the mechanism responsible for the observed helium in the brine is a continuous on-going process operative today. Diagenetic studies should then deal with both sands and shales interdependently, the two are not separable. Shales control the transport mechanisms of migration so that the primary migration of hydrocarbons, the result of kerogen catagenesis in shales, should occur sufficiently early in the sedimentary sequence in order to avoid exclusion from the reservoir by calcite cementation in association with radium transport. (author)

  20. Removal Capacities of Polycyclic Aromatic Hydrocarbons (PAHs by a Newly Isolated Strain from Oilfield Produced Water

    Directory of Open Access Journals (Sweden)

    Yi-Bin Qi

    2017-02-01

    Full Text Available The polycyclic aromatic hydrocarbon (PAH-degrading strain Q8 was isolated from oilfield produced water. According to the analysis of a biochemical test, 16S rRNA gene, house-keeping genes and DNA–DNA hybridization, strain Q8 was assigned to a novel species of the genus Gordonia. The strain could not only grow in mineral salt medium (MM and utilize naphthalene and pyrene as its sole carbon source, but also degraded mixed naphthalene, phenanthrene, anthracene and pyrene. The degradation ratio of these four PAHs reached 100%, 95.4%, 73.8% and 53.4% respectively after being degraded by Q8 for seven days. A comparative experiment found that the PAHs degradation efficiency of Q8 is higher than that of Gordonia alkaliphila and Gordonia paraffinivorans, which have the capacities to remove PAHs. Fourier transform infrared spectra, saturate, aromatic, resin and asphaltene (SARA and gas chromatography–mass spectrometry (GC–MS analysis of crude oil degraded by Q8 were also studied. The results showed that Q8 could utilize n-alkanes and PAHs in crude oil. The relative proportions of the naphthalene series, phenanthrene series, thiophene series, fluorene series, chrysene series, C21-triaromatic steroid, pyrene, and benz(apyrene were reduced after being degraded by Q8. Gordonia sp. nov. Q8 had the capacity to remediate water and soil environments contaminated by PAHs or crude oil, and provided a feasible way for the bioremediation of PAHs and oil pollution.

  1. Safety first: oilfield jobs sometimes go begging, but smart recruits pause for some training

    Energy Technology Data Exchange (ETDEWEB)

    Mowers, J.

    2000-05-01

    Occupational health and safety training available to prospective oilfield workers through the Petroleum Industry Training Service is discussed. The pre-employment program at PITS has been developed by the Canadian Association of Oilwell Drilling Contractors; about 240 students go through the program in an ordinary year. Training is done at the Nisku Campus of PITS and a second rig is waiting on standby for training at the site of the Leduc discovery near Devon. With both rigs in action, PITS will have the capacity to train up to 1,000 new hands a year. The course is also offered in Calgary where PITS is headquartered. The training is rigorous and hands-on; when not on the rig floor, students learn about off-the-rig jobs, such as mixing mud, packing gel, greasing, and digging ditches, in addition to more traditional 'book learning' about hydrogen sulphide, workplace hazardous materials, standard first aid and CPR. In addition to the pre-employment health and safety course, PITS also offers pre-employment programs for operators of production sites, including hands-on experience with an oil battery and gas plant at the Nisku campus. The pre-employment programs are supplementary to some 120 specialized course offered by PITS at Calgary and at numerous colleges and field locations.

  2. Strontium isotopes as natural tracers in reservoir oilfield and in groundwater systems

    International Nuclear Information System (INIS)

    Santos, Marcos E.; Palmieri, Helena E.L.; Moreira, Rubens M.

    2009-01-01

    The radioactive beta (β - ) decay of 87 Rb to 87 Sr is an important isotope system that has been widely applied for geochronological purposes and in identifying ground water sources, aquifer interactions and as a tracer for a secondary recovery process in offshore oilfields via seawater injection. The 87 Sr/ 86 Sr ratio of present seawater is constant worldwide, while formation waters in hydrocarbon reservoirs have various values are in most cases higher than modern seawater. This can be the basis for a natural tracer technique aiming at evaluating the performance of seawater injection processes by evaluating the 87 Sr/ 86 Sr ratio and the total Sr content of formation waters in the reservoir prior to injection, followed by monitoring these values in the produced water as injection proceeds. Inductively Couple Plasma Mass Spectrometry ICP-MS is a technique that has potential to be used in studies with tracers in the environment in the determination of isotope ratios and element traces in a sample. This work describes the methodology that will be used for the determination of variations in the isotopic composition of Sr and presents the preliminary results obtained determination of the strontium isotope ratios ( 87 Sr/ 86 Sr) using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). (author)

  3. Subsurface transport of inorganic and organic solutes from experimental road spreading of oil-field brine

    International Nuclear Information System (INIS)

    Bair, E.S.; Digel, R.K.

    1990-01-01

    A study designed to evaluate ground water quality changes resulting from spreading oil-field brine on roads for ice and dust control was conducted using a gravel roadbed that received weekly applications of brine eight times during the winter phase and 11 times during the summer phase of the study. A network of 11 monitoring wells and five pressure-vacuum lysimeters was installed to obtain ground water and soil water samples. Thirteen sets of water-quality samples were collected and analyzed for major ions, trace metals, and volatile organic compounds. Two sets of samples were taken prior to brine spreading, four sets during winter-phase spreading, five sets during summer-phase spreading, and two sets during the interim between the winter and summer phases. A brine plume delineated by elevated specific-conductance values and elevated chloride concentrations in ground water samples to exceed US EPA public drinking-water standards by two-fold during the winter phase and five-fold during the summer phase. No other major ions, trace metals, or volatile organic compounds exceeded the standards during the winter or summer phases. More than 99% dilution of the solutes in the brine occurred between the roadbed surface and the local ground water flow system. Further attenuation of calcium, sodium, potassium, and strontium resulted from adsorption, whereas further attenuation of benzene resulted from volatilization and adsorption

  4. Waste drilling-fluid-utilising microorganisms in a tropical mangrove swamp oilfield location

    Energy Technology Data Exchange (ETDEWEB)

    Benka-Coker, M.O.; Olumagin, A. [Benin Univ. (Nigeria). Dept. of Microbiology

    1995-12-31

    Waste drilling-fluid-utilising microorganisms were isolated from drilling-mud cuttings, soil and creek water from a mangrove swamp oilfield location in the Delta area of Nigeria using waste drilling-fluid as the substrate. Eighteen bacterial isolates obtained were identified as species of Staphylococcus, Acinetobacter, Alcaligenes, Serratia, Clostridium, Enterobacter, Klebsiella, Nocardia, Bacillus, Actinomyces, Micrococcus and Pseudomonas, while the genera of fungi isolated were Penicillium, Cladosporium and Fusarium. Even though drilling-fluid-utilising genera were in higher numbers in the soil than in the two other sources examined, the percentages of the total heterotrophic bacteria that utilised waste drilling-fluid were 6.02 in the drilling-mud cuttings, 0.83 in creek water and 0.42 in soil. The screen tests for biodegradation potential of the bacterial isolates showed that, even though all the isolates were able to degrade and utilise the waste fluid for growth, species of Alcaligenes and Micrococcus were more active degraders of the waste. The significance of the results in environmental management in oil-producing areas of Nigeria is discussed. (Author)

  5. Microbiological Diversity of the Anaerobic Sludge During Treatment of Venezuelan Oilfield Produced Waters

    Directory of Open Access Journals (Sweden)

    Cajacuri María Patricia

    2013-06-01

    Full Text Available In the present investigation the microbial abundances in the granular sludge of two upflow anaerobic sludge blanket reactors (UASB were compared: the first one fed with production waters of light oil (31.1-39.0° API, from the zuliana region (Venezuela (APP and the second one with glucose. To this respect, the populations of glucose fermenting bacteria (BFG, acetogenic bacteria (BAC, metanogens (MET, sulfatereducing bacteria (BSR, nitrate-reducing bacteria (BNRand heterotrophic bacteria were monitored, using selective culture media. The microbial density was correlated with physicochemical parameters: pH, total alkalinity, COD, SO4 =, NO3-, as well as with the percentages of CH4, CO2 and N2in the biogas. The results exhibit significant differences between the microbial diversity of both reactors, with a proportion of BFG > BSR > MET > BAC > BNR for the glucose reactor and of MET > BNR > BAC > BSR > BFG for the APP. The abundance of bacteria in the glucose reactor was in the order of 108, whereas in the APP reactor was of 105, which ensues from the organic and mineral composition of effluents. The results presented in this study reach evidences on the population dynamics in sludge of UASB reactors, during the treatment of oilfield produced waters.

  6. Localized corrosion of carbon steel in a CO{sub 2}-saturated oilfield formation water

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, G.A. [Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, AB, T2N 1N4 (Canada); Cheng, Y.F., E-mail: fcheng@ucalgary.c [Department of Mechanical and Manufacturing Engineering, University of Calgary, Calgary, AB, T2N 1N4 (Canada)

    2011-01-01

    In this work, corrosion and localized corrosion behavior of X65 pipeline steel were studied in a simulated, CO{sub 2}-saturated oilfield formation water by various electrochemical measurement techniques, including electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curves, galvanic current and localized EIS (LEIS). The morphology and composition of the formed corrosion scale were characterized by scanning electron microscopy and energy-dispersive X-ray analysis. A conceptual model was developed to illustrate the occurrence of localized corrosion of the steel under scale. Both galvanic current and LEIS measurements showed that a galvanic effect existed between the bare steel and the scale-covered region. The scale-covered region served as cathode and the bare steel site as the anode. The big cathode vs. small anode geometry accelerated the local corrosion reaction. At an elevated temperature, a compact, crystalline scale was formed on the steel surface, enhancing the galvanic effect. Moreover, the stability of the scale was increased with time, and localized corrosion of the steel under scale experienced mechanistic changes with time.

  7. Behavior of gellan in aqueous-salt solutions and oilfield saline water

    Directory of Open Access Journals (Sweden)

    Zhanar Nurakhmetova

    2015-09-01

    Full Text Available The influence of storage time and temperature on the behavior of low acyl gellan (LAG was studied by viscometry and 1H NMR spectroscopy without salt addition. The viscometric results revealed that the effectiveness of salts to enhance gelation of gellan changes in the following order: BaСl2>CaCl2»MgCl2>KCl>NaCl. The sol-gel and liquid-solid phase transitions of gellan solutions were observed upon addition of oilfield water containing 73 g L-1 of alkaline and alkaline earth metal ions. The effectiveness of salts to induce the separation of liquid and solid phases changes in the sequence: NaCl>KCl>MgCl2»CaCl2»BaСl2. The hydrodynamic behavior of 0.5 wt.% gellan solution injected into the sand pack model with high (20 Darcy and lower (2 Darcy permeability is useful to model the oil reservoirs in the process of enhanced oil recovery.

  8. Studies on a Foam System of Ultralow Interfacial Tension Applied in Daqing Oilfield after Polymer Flooding

    Directory of Open Access Journals (Sweden)

    Hong-sheng Liu

    2013-01-01

    Full Text Available In order to study the effects of oil displacement by a foam system of ultralow interfacial tension, the interfacial activities and foam properties of a nonionic gemini surfactant (DWS were investigated under Daqing Oilfield reservoir conditions. Injection methods and alternate cycle of the foam system were discussed here on the basis of results from core flow experiments. It was obtained that the surface tension of DWS was approximately 25 mN/m, and ultralow interfacial tension was reached between oil and DWS with a surfactant concentration between 0.05wt% and 0.4wt%. The binary system showed splendid foam performances, and the preferential surfactant concentration was 0.3wt% with a polymer concentration of 0.2wt%. When gas and liquid were injected simultaneously, flow control capability of the foam reached its peak at the gas-liquid ratio of 3 : 1. Enhanced oil recovery factor of the binary foam system exceeded 10% in a parallel natural cores displacement after polymer flooding.

  9. Environmentally safe oil-field reagents for development and operation of oil-gas deposits

    Science.gov (United States)

    Fakhreeva, A. V.; Manaure, D. A.; Dokichev, V. A.; Voloshin, A. I.; Telin, A. G.; Tomilov, Yu V.; Nifantiev, N. E.

    2018-04-01

    Sodium-carboxymethylcellulose and arabinogalactane inhibits the crystallization of calcium carbonate from a supersaturated aqueous solution at 80°C. The sizes of formed crystals CaCO3 in the presence of arabinogalactane, sodium-carboxymethylcellulose and neonol AF 9-10 decrease on an average 7-12 μm and a change of their structure. It is expected, that the mechanism of inhibitionis in specific adsorption polysaccharides and neonol on occurring crystalline surface of the calcium carbonate, both at the expense of electrostatic interaction of functional groups with Ca2+ ions, located on the surface of the crystal, and due to coordination and hydrogen bonds with oxygen atoms and HO-groups of additives. Oil-water emulsion rheology in the presence of neonol AF 9-10 has been studied. It is shown that neonol AF 9-10 decrease viscosity natural water-oil emulsion by 25 times. Addition of 5% neonol to water-oil emulsion leads to formation more than 20 stable emulsion forms of different density and composition. New highly effective “green” oilfield reagents have been developed on the basis of neonol and natural polysaccharides.

  10. Study and application of weak gel used for an offshore oilfield

    Energy Technology Data Exchange (ETDEWEB)

    Tang, X.; Liu, Y.; Bai, B.; Liu, G.; Jiang, R. [Petro-China Research Inst. of Petroleum Exploration and Development, Beijing (China); Xiang, W. [China Offshore Oil Research Center of China National Offshore Oil Co. (China)

    2005-07-01

    This paper described the profile modification technique which has been used successfully in China's oil fields on land and which has become one of the key techniques to improve the development of mature fields with high heterogeneity and high water cut. One such reservoir is SZ361, an offshore oilfield characterized by thick oil layers, high permeability contrast, high oil viscosity and high water salinity. All injection wells were completed by liner gravel-packing. Water cut of some production wells is above 90 per cent. A large volume of weak gel treatment was proposed to control water conformance. A new weak gel was developed to address the specific features of offshore oil fields, such as small space of platform and high salinity of injection water. The gel properties were presented along with an evaluation of the salinity and temperature on the thermal stability of the gel. The plugging efficiency of the gel was carried out on different permeability cores. Results show that the selected polymer and cross-linkers can be well dispersed and solved within 30 minutes when mixing with sea water or produced water. The gelation time can be controlled by adjusting the gel composition. The novel gel can be applied in the reservoirs with a temperature range of 30-70 degrees C and salinity below 40,000 mg/l. The gel was tested in one injection well and proved to be economically efficient. 7 refs., 3 tabs., 8 figs.

  11. [Compositions and residual properties of petroleum hydrocarbon in contaminated soil of the oilfields].

    Science.gov (United States)

    Hu, Di; Li, Chuan; Dong, Qian-Qian; Li, Li-Ming; Li, Guang-He

    2014-01-01

    The aims of this study were to determine the compositions and residual properties of petroleum hydrocarbon in soil, as well as to identify the source and weathering degree of the pollution. A total of 5 producing wells in Gudao and Hekou oil producing region of Shengli oilfields were analyzed. More than 50 individual target compounds including straight-and branched-chain alkanes( n-alkanes, pristine and phytane) and polycyclic aromatic hydrocarbons (PAHs) in soil samples and crude oil were determined by gas chromatography-mass spectrometry (GC-MS). The percentages of chain alkanes and PAHs in total solvent extractable matters(TSEM) of soil samples were both much lower than those in the crude oil samples. The compositions of petroleum hydrocarbon in soil samples differed from those in crude oil, which indicated the n-alkanes with carbon numbers contaminated soils, the relationship between the index and petroleum hydrocarbon compounds was analyzed using principal component analysis (PCA). The results showed that the n-alkanes with carbon numbers > 33 and the PAHs with rings between 3 and 5 were much harder to degrade. PCA of 4 indexes for source identification revealed more than 50% of the soil samples were polluted by crude oil, which needs more attention during remediation.

  12. Financial oil derivatives: from options to oil warrants and synthetic oilfields

    International Nuclear Information System (INIS)

    Trabia, Xavier

    1992-01-01

    This study aims to shed light on some of the most interesting financial oil derivatives issued so far in order to assess the potential of this new wave of innovative funding instruments. In Part I some theoretical background is provided and applied to the problem of the American futures option. The ''binomial'' model for valuing future option contracts is presented and the most accurate alternatives for pricing American futures options are reviewed. The role of these numerical procedures in valuing more complex options involved in oil warrants is examined. Comments are made on the behaviour of volatility, which stands as a key interface between theory and practice in oil trading on the oil futures market. Part II of the study describes in detail some of the most famous new financial oil derivatives. Some final conclusions are drawn on the potential of oil trusts and synthetic oilfields to be involved in project and general funding in the oil industry. (44 figures, 11 tables, 53 references) (UK)

  13. 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...

  14. A New Software for Management, Scheduling, and Optimization for the Light Hydrocarbon Pipeline Network System of Daqing Oilfield

    Directory of Open Access Journals (Sweden)

    Yongtu Liang

    2014-01-01

    Full Text Available This paper presents the new software which specifically developed based on Visual Studio 2010 for Daqing Oilfield China includes the most complex light hydrocarbon pipeline network system in Asia, has become a powerful auxiliary tool to manage field data, makes scheduling plans for batching operation, and optimizes pumping plans. Firstly, DMM for recording and managing field data is summarized. Then, the batch scheduling simulation module called SSM for the difficult batch-scheduling issues of the multiple-source pipeline network system is introduced. Finally, SOM, that is Scheduling Optimization Module, is indicated for solving the problem of the pumps being started up/shut-down frequently.

  15. Hydrogen embrittlement: the game changing factor in the applicability of nickel alloys in oilfield technology

    Science.gov (United States)

    Sarmiento Klapper, Helmuth; Klöwer, Jutta; Gosheva, Olesya

    2017-06-01

    Precipitation hardenable (PH) nickel (Ni) alloys are often the most reliable engineering materials for demanding oilfield upstream and subsea applications especially in deep sour wells. Despite their superior corrosion resistance and mechanical properties over a broad range of temperatures, the applicability of PH Ni alloys has been questioned due to their susceptibility to hydrogen embrittlement (HE), as confirmed in documented failures of components in upstream applications. While extensive work has been done in recent years to develop testing methodologies for benchmarking PH Ni alloys in terms of their HE susceptibility, limited scientific research has been conducted to achieve improved foundational knowledge about the role of microstructural particularities in these alloys on their mechanical behaviour in environments promoting hydrogen uptake. Precipitates such as the γ', γ'' and δ-phase are well known for defining the mechanical and chemical properties of these alloys. To elucidate the effect of precipitates in the microstructure of the oil-patch PH Ni alloy 718 on its HE susceptibility, slow strain rate tests under continuous hydrogen charging were conducted on material after several different age-hardening treatments. By correlating the obtained results with those from the microstructural and fractographic characterization, it was concluded that HE susceptibility of oil-patch alloy 718 is strongly influenced by the amount and size of precipitates such as the γ' and γ'' as well as the δ-phase rather than by the strength level only. In addition, several HE mechanisms including hydrogen-enhanced decohesion and hydrogen-enhanced local plasticity were observed taking place on oil-patch alloy 718, depending upon the characteristics of these phases when present in the microstructure. This article is part of the themed issue 'The challenges of hydrogen and metals'.

  16. Total petroleum hydrocarbon degradation by hybrid electrobiochemical reactor in oilfield produced water

    International Nuclear Information System (INIS)

    Mousa, Ibrahim E.

    2016-01-01

    The crude oil drilling and extraction operations are aimed to maximize the production may be counterbalanced by the huge production of contaminated produced water (PW). PW is conventionally treated through different physical, chemical, and biological technologies. The efficiency of suggested hybrid electrobiochemical (EBC) methods for the simultaneous removal of total petroleum hydrocarbon (TPH) and sulfate from PW generated by petroleum industry is studied. Also, the factors that affect the stability of PW quality are investigated. The results indicated that the effect of biological treatment is very important to keep control of the electrochemical by-products and more TPH removal in the EBC system. The maximum TPH and sulfate removal efficiency was achieved 75% and 25.3%, respectively when the detention time was about 5.1 min and the energy consumption was 32.6 mA/cm 2 . However, a slight increasing in total bacterial count was observed when the EBC compact unit worked at a flow rate of average 20 L/h. Pseudo steady state was achieved after 30 min of current application in the solution. Also, the results of the study indicate that when the current intensity was increased above optimum level, no significant results occurred due to the release of gases. - Highlights: • The hybrid electrolytic biological cell was used for degradation of oilfield produced water. • Decomposition of Total Petroleum Hydrocarbon with or without the biofilter. • High saline water with the high chloride and sulfate ions content treatment. • The removal of electrochemical by-products is a phase change technique that requires the maintenance the biofilm on the filter media, which is sensitive and a complex operation. • Biofilter is efficient for the degradation of PW bye products, the critical drawback to their utility in full-scale operations is high TDS water content and detention time of treatment.

  17. Hierarchical Material Properties in Finite Element Analysis: The Oilfield Infrastructure Problem.

    Science.gov (United States)

    Weiss, C. J.; Wilson, G. A.

    2017-12-01

    Geophysical simulation of low-frequency electromagnetic signals within built environments such as urban centers and industrial landscapes facilities is a challenging computational problem because strong conductors (e.g., pipes, fences, rail lines, rebar, etc.) are not only highly conductive and/or magnetic relative to the surrounding geology, but they are very small in one or more of their physical length coordinates. Realistic modeling of such structures as idealized conductors has long been the standard approach; however this strategy carries with it computational burdens such as cumbersome implementation of internal boundary conditions, and limited flexibility for accommodating realistic geometries. Another standard approach is "brute force" discretization (often coupled with an equivalent medium model) whereby 100's of millions of voxels are used to represent these strong conductors, but at the cost of extreme computation times (and mesh design) for a simulation result when possible. To minimize these burdens, a new finite element scheme (Weiss, Geophysics, 2017) has been developed in which the material properties reside on a hierarchy of geometric simplicies (i.e., edges, facets and volumes) within an unstructured tetrahedral mesh. This allows thin sheet—like structures, such as subsurface fractures, to be economically represented by a connected set of triangular facets, for example, that freely conform to arbitrary "real world" geometries. The same holds thin pipe/wire-like structures, such as casings or pipelines. The hierarchical finite element scheme has been applied to problems in electro- and magnetostatics for oilfield problems where the elevated, but finite, conductivity and permeability of the steel-cased oil wells must be properly accounted for, yielding results that are otherwise unobtainable, with run times as low as a few 10s of seconds. Extension of the hierarchical finite element concept to broadband electromagnetics is presently underway, as

  18. Distribution characteristics of terrestrial heat flow density in Jiyang depression of Shengli Oilfield, East China

    Institute of Scientific and Technical Information of China (English)

    GONG; Yuling; WANG; Liangshu; LIU; Shaowen; LI; Cheng; HAN

    2004-01-01

    Based on the geo-temperature data of 13 systematically continuous temperature log curves and 700 testing oil boreholes in Jiyang depression, Shengli Oilfield, and the measured thermal conductivities of 47 rock samples, the terrestrial heat flow densities of 114 boreholes of Jiyang depression and its surrounding areas are determined, including 13 of those data derived from systemically continuous temperature logging. The results show that Jiyang depression has a relatively high background heat flow with an average value (65.8 ± 5.4) mW/m2. The lateral variation of heat flow in basin has negative correlation with basement depth. Moreover, heat flow of uplift areas with shallower basement is high, so are those of regions with volcanic rocks, and those of depression areas with deep basement are relatively low. The heat flow densities of different structural units of Jiyang depression can be summarized as follows: The average heat flow value of Zhanhua sag is (67.4 ± 5.3) mW/m2, higher than that of the whole basin, that of Dongying sag is (66.0 ± 6.1) mW/m2, and that of Chezhen sag is (65.1 ± 3.7) mW/m2. It is apparent that these latter two values are approximate to the average value of the whole Jiyang depression,while the average value of Huimin sag is (63.6±5.0) mW/m2, lower than that of the whole basin. In fact, the basement depth and the distribution framework of uplift and depression areas are all controlled by the process of lithosphere extension. In addition, the distribution of volcanic rocks in basin is also relatively close to this extension geodynamic process. In summary, the distribution characteristics of terrestrial heat flow of Jiyang depression is determined by the Cenozoic tectono-thermal events of this region.

  19. How Talisman Energy implemented oilfield fleet safety using event driven AVL technologies from TELUS

    Energy Technology Data Exchange (ETDEWEB)

    Munroe, D. [Telus Energy Sector Organization, Calgary, AB (Canada)

    2006-07-01

    This conference presentation provided information on how Talisman Energy implemented oilfield fleet safety using event driven automated vehicle location (AVL) technologies from TELUS. Background information on Telus in the energy sector, Telus geomatics, Telus mobile resource management (MRM) application modules, as well as Talisman Energy was first provided. Talisman looked to Telus for AVL technologies because it had a need to identify where employees were working, when they arrived and how long they were there. Prior to meeting with TELUS, Talisman Energy had implemented a system consisting of a trunk radio network to transmit data to the control room on the employee's location, however, it was unable to use the radio network to dispatch orders and communicate on an as-needed basis. TELUS had implemented a customized solution that tracks vehicles and provides an easy method of communication for employees to track how long they are working at a site. The service provides the control centre with the tools to monitor the location of the vehicles on a map, and communicate to the employee via a horn when their time has expired at the site. If the employee does not respond, the control room can call the nearest personnel to check on the worker's status. The integrated TELUS solutions uses Global Positioning System (GPS), Geographic Information Systems (GIS) and Wireless communication over the Internet. The presentation provided numerous Talisman specific maps. It concluded with several issues to consider such as cross platform cellular communications supported on a single hardware platform; additional support for Satellite communications utilizing the same GIS platform; the need for extensive support for peripheral devices; and, the need for extensive roaming capabilities. tabs., figs.

  20. Electricity generation from enhanced geothermal systems by oilfield produced water circulating through reservoir stimulated by staged fracturing technology for horizontal wells: A case study in Xujiaweizi area in Daqing Oilfield, China

    International Nuclear Information System (INIS)

    Zhang, Yan-Jun; Li, Zheng-Wei; Guo, Liang-Liang; Gao, Ping; Jin, Xian-Peng; Xu, Tian-Fu

    2014-01-01

    In this paper, the feasibility of generating electricity from EGS (enhanced geothermal systems) by oilfield produced water circulating through reservoir stimulated by staged fracturing technology for horizontal wells is investigated based on the geological data of Xujiaweizi area, located in the Daqing Oilfield, northeast China. HDR (hot dry rock) resource potential assessment is carried out by using volumetric method. Reservoir stimulation is numerically simulated based on the geological data of well YS-1 and field fracturing experience in this region. Geometric dimensions and flow conductivity of the resulting fracture are imported into the hydro-thermal model to calculate the electricity generation potential of the proposed EGS power plant. An EGS design scheme is proposed based on the simulation results. The system is also evaluated from the economic and environmental aspects. The results indicate that HDR resource in Xujiaweizi area is of great potential for development. Through the staged fracturing technology for horizontal wells, electricity generation power of the proposed EGS project can roughly meet the commercial standard. For 20 years of continuous production, power generation from the proposed EGS power plant is economic feasible. Meanwhile, significant reductions in greenhouse gas emissions can be achieved. - Highlights: • Staged fracturing technology for horizontal well is used in HDR (hot dry rock) development. • Fracturing simulations and heat production simulations are combined. • A 3 MW power plant is designed in Xujiaweizi based on the simulation results

  1. Energy Return on Investment (EROI) for Forty Global Oilfields Using a Detailed Engineering-Based Model of Oil Production

    Science.gov (United States)

    Brandt, Adam R.; Sun, Yuchi; Bharadwaj, Sharad; Livingston, David; Tan, Eugene; Gordon, Deborah

    2015-01-01

    Studies of the energy return on investment (EROI) for oil production generally rely on aggregated statistics for large regions or countries. In order to better understand the drivers of the energy productivity of oil production, we use a novel approach that applies a detailed field-level engineering model of oil and gas production to estimate energy requirements of drilling, producing, processing, and transporting crude oil. We examine 40 global oilfields, utilizing detailed data for each field from hundreds of technical and scientific data sources. Resulting net energy return (NER) ratios for studied oil fields range from ≈2 to ≈100 MJ crude oil produced per MJ of total fuels consumed. External energy return (EER) ratios, which compare energy produced to energy consumed from external sources, exceed 1000:1 for fields that are largely self-sufficient. The lowest energy returns are found to come from thermally-enhanced oil recovery technologies. Results are generally insensitive to reasonable ranges of assumptions explored in sensitivity analysis. Fields with very large associated gas production are sensitive to assumptions about surface fluids processing due to the shifts in energy consumed under different gas treatment configurations. This model does not currently include energy invested in building oilfield capital equipment (e.g., drilling rigs), nor does it include other indirect energy uses such as labor or services. PMID:26695068

  2. Profiling microbial community structures across six large oilfields in China and the potential role of dominant microorganisms in bioremediation.

    Science.gov (United States)

    Sun, Weimin; Li, Jiwei; Jiang, Lei; Sun, Zhilei; Fu, Meiyan; Peng, Xiaotong

    2015-10-01

    Successful bioremediation of oil pollution is based on a comprehensive understanding of the in situ physicochemical conditions and indigenous microbial communities as well as the interaction between microorganisms and geochemical variables. Nineteen oil-contaminated soil samples and five uncontaminated controls were taken from six major oilfields across different geoclimatic regions in China to investigate the spatial distribution of the microbial ecosystem. Microbial community analysis revealed remarkable variation in microbial diversity between oil-contaminated soils taken from different oilfields. Canonical correspondence analysis (CCA) further demonstrated that a suite of in situ geochemical parameters, including soil moisture and sulfate concentrations, were among the factors that influenced the overall microbial community structure and composition. Phylogenetic analysis indicated that the vast majority of sequences were related to the genera Arthrobacter, Dietzia, Pseudomonas, Rhodococcus, and Marinobacter, many of which contain known oil-degrading or oil-emulsifying species. Remarkably, a number of archaeal genera including Halalkalicoccus, Natronomonas, Haloterrigena, and Natrinema were found in relatively high abundance in some of the oil-contaminated soil samples, indicating that these Euryarchaeota may play an important ecological role in some oil-contaminated soils. This study offers a direct and reliable reference of the diversity of the microbial community in various oil-contaminated soils and may influence strategies for in situ bioremediation of oil pollution.

  3. Energy Return on Investment (EROI for Forty Global Oilfields Using a Detailed Engineering-Based Model of Oil Production.

    Directory of Open Access Journals (Sweden)

    Adam R Brandt

    Full Text Available Studies of the energy return on investment (EROI for oil production generally rely on aggregated statistics for large regions or countries. In order to better understand the drivers of the energy productivity of oil production, we use a novel approach that applies a detailed field-level engineering model of oil and gas production to estimate energy requirements of drilling, producing, processing, and transporting crude oil. We examine 40 global oilfields, utilizing detailed data for each field from hundreds of technical and scientific data sources. Resulting net energy return (NER ratios for studied oil fields range from ≈2 to ≈100 MJ crude oil produced per MJ of total fuels consumed. External energy return (EER ratios, which compare energy produced to energy consumed from external sources, exceed 1000:1 for fields that are largely self-sufficient. The lowest energy returns are found to come from thermally-enhanced oil recovery technologies. Results are generally insensitive to reasonable ranges of assumptions explored in sensitivity analysis. Fields with very large associated gas production are sensitive to assumptions about surface fluids processing due to the shifts in energy consumed under different gas treatment configurations. This model does not currently include energy invested in building oilfield capital equipment (e.g., drilling rigs, nor does it include other indirect energy uses such as labor or services.

  4. The use of modern on-site bioremediation systems to reduce crude oil contamination on oilfield properties

    International Nuclear Information System (INIS)

    Hildebrandt, W.W.; Wilson, S.B.

    1991-01-01

    Oil-field properties frequently have areas in which the soil has been degraded with crude oil. Soil contaminated in this manner is often considered either a hazardous waste or designated waste under regulatory guidelines. As a result, there is often concern about an owner's liabilities and the financial institution's liabilities whenever oilfield properties are transferred to new operators, abandoned, or converted to other uses such as real estate. There is also concern about the methods and relative costs to remediate soil which has been contaminated with crude oil. Modern, well-designed, soil bioremediation systems are cost effective for the treatment of crude oil contamination, and these systems can eliminate an owner's subsequent liabilities. Compared to traditional land-farming practices, a modern on-site bioremediation system (1) requires significantly less surface area, (2) results in lower operating costs, and (3) provides more expeditious results. Compared to excavation and off-site disposal of the contaminated soil, on-site bioremediation will eliminate subsequent liabilities and is typically more cost effective. Case studies indicate that o-site bioremediation systems have been successful at reducing the crude oil contamination in soil to levels which are acceptable to regulatory agencies in less than 10 weeks. Total costs for on-site bioremediation has ranged from $35 to $40 per cubic yard of treated soil, including excavation

  5. Identification of components contents of oil extracts and its aromatic fractions. Extracted from oil-polluted soils of Surakhany oilfield of Apsheron peninsula

    International Nuclear Information System (INIS)

    Abbasova, D.R.; Kerimov, M.K.; Cafarova, R.A.

    2010-01-01

    In this work have been studied components content of oil extracts and its aromatic fraction of Surakhany oilfield by DSC and TGA in follow temperature interval 20-500 degrees Celsium. Have been identified that low paraffinicity of oil fraction and oil extract and its aromatic fraction in this investigation show to young geological age (low transformation) of this oil.

  6. 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 in...

  7. 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 the...

  8. 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...

  9. 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...

  10. Treatment of oilfield wastewater by combined process of micro-electrolysis, Fenton oxidation and coagulation.

    Science.gov (United States)

    Zhang, Zhenchao

    2017-12-01

    In this study, a combined process was developed that included micro-electrolysis, Fenton oxidation and coagulation to treat oilfield fracturing wastewater. Micro-electrolysis and Fenton oxidation were applied to reduce chemical oxygen demand (COD) organic load and to enhance organic components gradability, respectively. Orthogonal experiment were employed to investigate the influence factors of micro-electrolysis and Fenton oxidation on COD removal efficiency. For micro-electrolysis, the optimum conditions were: pH, 3; iron-carbon dosage, 50 mg/L; mass ratio of iron-carbon, 2:3; reaction time, 60 min. For Fenton oxidation, a total reaction time of 90 min, a H 2 O 2 dosage of 12 mg/L, with a H 2 O 2 /Fe 2+ mole ratio of 30, pH of 3 were selected to achieve optimum oxidation. The optimum conditions in coagulation process: pH, cationic polyacrylamide dosage, mixing speed and time is 4.3, 2 mg/L, 150 rpm and 30 s, respectively. In the continuous treatment process under optimized conditions, the COD of oily wastewater fell 56.95%, 46.23%, 30.67%, respectively, from last stage and the total COD removal efficiency reached 83.94% (from 4,314 to 693 mg/L). In the overall treatment process under optimized conditions, the COD of oily wastewater was reduced from 4,314 to 637 mg/L, and the COD removal efficiency reached 85.23%. The contribution of each stage is 68.45% (micro-electrolysis), 24.07% (Fenton oxidation), 7.48% (coagulation), respectively. Micro-electrolysis is the uppermost influencing process on COD removal. Compared with the COD removal efficiency of three processes on raw wastewater under optimized conditions: the COD removal efficiency of single micro-electrolysis, single Fenton oxidation, single coagulation is 58.34%, 44.88% and 39.72%, respectively. Experiments proved the effect of combined process is marvelous and the overall water quality of the final effluent could meet the class III national wastewater discharge standard of petrochemical industry of China

  11. Multiple generations of high salinity formation water in the Triassic Sherwood Sandstone: Wytch Farm oilfield, onshore UK

    International Nuclear Information System (INIS)

    Worden, R.H.; Manning, D.A.C.; Bottrell, S.H.

    2006-01-01

    The origin and heterogeneity of oilfield formation water in the Lower Triassic Sherwood Sandstone at Wytch Farm in the Wessex Basin, UK, have been investigated using production data, detailed water geochemistry and O, S and H stable isotope data. The formation waters are highly saline, NaCl-type brines with TDS values of up to 230,000mg/L. There is a general decrease in salinity from the flanks of the field to the crest with Cl - decreasing from about 136,000 to 109,000mg/L. The Cl/Br ratio of the water shows that salinity was largely derived from the dissolution of Upper Triassic continental evaporites found off-structure to the west and north of the field. The water in the field had a meteoric source although variation in δ 2 H values suggests that there may be meteoric waters of different ages in the oilfield, reflecting recharge under different palaeoclimatic conditions. At the crest of the field, aqueous SO 4 2- resulted from dissolution of anhydrite in the reservoir. In contrast, in other parts of the field there is an indication that some of the dissolved SO 4 2- was derived from oxidation of pyrite at some point on the recharge path of meteoric water to the field. There were two meteoric influx events bringing different Cl - concentrations and different δ 2 H values. The first was probably before the Eocene oil influx and could have occurred in the Lower Cretaceous or early Tertiary. The second meteoric influx event probably occurred after or during oil migration into the Wytch Farm structure since the second meteoric water is found at the flanks of the field adjacent to the regions where salt is found in the stratigraphy. The preservation of heterogeneities in oilfield formation water compositions suggests that there has been little aqueous fluid movement or diffusive flux for over 40 million years. Mass flux has been restricted by density stratification within the aquifer and the very low effective permeability for the aqueous phase in the oil

  12. 75 FR 11837 - Chesapeake Bay Watershed Initiative

    Science.gov (United States)

    2010-03-12

    ... DEPARTMENT OF AGRICULTURE Commodity Credit Corporation Chesapeake Bay Watershed Initiative AGENCY...: Notice of availability of program funds for the Chesapeake Bay Watershed Initiative. SUMMARY: The... through the Chesapeake Bay Watershed Initiative for agricultural producers in the Chesapeake Bay watershed...

  13. 33 CFR 100.124 - Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York. 100.124 Section 100.124 Navigation and Navigable... NAVIGABLE WATERS § 100.124 Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York...

  14. Oilfield development and protection of natural resources within the tropical marine environment of the Rowley shelf, northwest Australia

    International Nuclear Information System (INIS)

    LeProvost, M.I.; Gordon, D.M.

    1991-01-01

    In recent years a number of oilfields have been developed in tropical waters of the Rowley Shelf, north-west Australia. Along with Bass Strait and the Timor Sea, this region is the focus for Australia's current oil exploration and production. It supports major coral and mangrove habitats and fishing grounds sensitive to the effects of oil pollution. This paper provides a synthesis of the Rowley Shelf marine environment and reviews procedures protecting the marine resources of the region from the effects of oil spills. Recent government and industry initiatives for improving the protection of the environment are outlined and discussed on the basis of the improved understanding of the marine resources and experience being gained in oil spill contingency planning. The tropical habitats of the Rowley Shelf occur within the Indo-Pacific Zoogeographic Region, therefore experience gained in Western Australia is applicable to similar environments in the South East Asian region

  15. INEEL Biotechnology for Oilfield Application--Microbial Enhanced Oil Recovery FY-03 Report

    Energy Technology Data Exchange (ETDEWEB)

    G. A. Bala; D. F. Bruhn; S. L. Fox; K. S. Noah; K. D. Schaller; E. P. Robertson; X. Xie

    2003-11-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) Biotechnology for Oilfield Operations program supports development, engineering, and application of biotechnology for exploration and production. This continuing INEEL program also supports mitigation of detrimental field conditions. The program is consistent with the United States Department of Energy mission to ¡§promote activities and policies through its oil technology and natural gas supply programs to enhance the efficiency and environmental quality of domestic oil and natural gas exploration, recovery, processing, transport, and storage.¡¨ In addition, the program directly supports the focus areas of Reservoir Life Extension; Advanced Drilling, Completion and Stimulation Systems; Effective Environmental Protection; and Cross Cutting Areas. The program is enhanced by collaborative relationships with industry and academia. For fiscal year 2003, the program focused on production and characterization of biological surfactants from agricultural residuals and the production and application of reactive microbial polymers. This report specifically details: 1. Use of a chemostat reactor operated in batch mode for producing surfactin, with concomitant use of an antifoam to prevent surfactant loss. The program achieved production and recovery of 0.6 g/L of surfactin per 12 hr. 2. Characterization of surfactin produced from agricultural residuals with respect to its ability to mediate changes in surface tension. Conditions evaluated were salt (as NaCl) from 0 to 10% (w/v), pH from 3 to 10, temperature from 21 to 70¢XC, and combinations of these conditions. When evaluated singularly, pH below 6 and salt concentrations above 30 g/L were found to have an adverse impact on surfactin. Temperatures of 70¢XC for 95 days had no effect. When the effect of temperature was added to the pH experiment, there were no significant changes, and, again, surface tension, at any temperature, increased at pH below 6

  16. The value of smart artificial lift technology in mature field operations demonstrated in the Zistersdorf oilfield in Austria

    Energy Technology Data Exchange (ETDEWEB)

    Muessig, S.; Oberndorfer, M.; Rice, D. [Rohoelaufsuchungs-AG, Wien (Austria); Soliman, K. [Montanuniversitaet Leoben (Austria)

    2013-08-01

    Currently, approximately 40% of world oil production comes from mature fields and the tendency is that this will increase with time. A significant portion of operational expenditures in mature oil fields is related to lifting costs including the cost of maintenance of the artificial lift equipment. In many cases additional, unnecessary, costs are incurred due to inadequate control of corrosion and sand production leading to premature failures of the equipment and thus to additional workover operations. In mature fields this can result in a significant loss of reserves when the production has to be abandoned prematurely because workover operations become uneconomic. In order to combat such losses of reserves RAG and its partners have developed fit-for-purpose technologies such as: continuous control of the liquid level in the annulus (i.e. bottom hole flowing pressure), innovative advanced sand control and longer lasting artificial lift equipment. On the basis of the 75 years old Zistersdorf oilfields the value of these developments in artificial lift technology is demonstrated. The Zistersdorf oilfields produce primarily from the compacted and fairly permeable 'Sarmat' sandstone formation which has many layers whereby the higher layers are poorly consolidated. The fields are currently producing from 33 producing wells some 6 900 m{sup 3} (Vn)/d gas and 48 t/d of oil at an average water cut of 97.1%. It will be shown that the implementation of the technologies described in combination with the in-house knowledge and the dedication of the field staff has extended considerably the mean time between failures of the equipment, reduced markedly the average yearly decline rate and thus extended the economic life expectancy of the fields and increased the ultimate recovery significantly.

  17. A risk assessment approach to identifying constituents in oilfield produced water for treatment prior to beneficial use.

    Science.gov (United States)

    Horner, Jennifer E; Castle, James W; Rodgers, John H

    2011-05-01

    A risk assessment approach incorporating exposure pathways and calculated risk quotients was applied to identifying constituents requiring treatment prior to beneficial use of oilfield produced water (OPW). In this study, risk quotients are ratios of constituent concentrations in soil or water to guideline concentrations for no adverse effects to receptors. The risk assessment approach is illustrated by an example of an oilfield water produced from non-marine geologic strata of a rift basin in sub-Saharan Africa. The OPW studied has the following characteristics: 704-1370 mg L(-1) total dissolved solids (TDS), 45-48 mg L(-1) chloride, and 103.8 mg L(-1) oil and grease. Exposure pathways of constituents in OPW used for irrigation include: ingestion of plant tissue, ingestion and direct contact of irrigated soil by livestock, inhalation of aerosols or volatilized constituents, and ingestion of OPW directly by livestock. Applying risk quotient methods for constituents in soil and water, constituents of concern (COCs) identified for irrigation and livestock watering using the OPW studied include: iron (Fe), manganese (Mn), nickel (Ni), zinc (Zn), and oil and grease. Approximately 165,000 barrels d(-1) (26,233 m(3) d(-1)) of OPW from the study site are available for use. Identification of COCs and consideration of water quantity allows for development of reliable treatment design criteria to ensure effective and consistent treatment is achieved to meet guideline levels required for irrigation, livestock watering, or other uses. This study illustrates the utility of risk assessment for identifying the COCs in OPW for treatment, the level of treatment required, and viable options for use of the treated water. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Chesapeake Bay under stress

    Science.gov (United States)

    According to extensive data obtained over its 13,000 km of shoreline, the Chesapeake Bay has been suffering a major, indeed unprecedented, reduction in submerged vegetation. Chesapeake Bay is alone in experiencing decline in submerged vegetation. Other estuary systems on the east coast of the United States are not so affected. These alarming results were obtained by the synthesis of the findings of numerous individual groups in addition to large consortium projects on the Chesapeake done over the past decade. R. J. Orth and R. A. Moore of the Virginia Institute of Marine Science pointed to the problem of the severe decline of submerged grasses on the Bay and along its tributaries. In a recent report, Orth and Moore note: “The decline, which began in the 1960's and accelerated in the 1970's, has affected all species in all areas. Many major river systems are now totally devoid of any rooted vegetation” (Science, 222, 51-53, 1983).

  19. Mobile Bay turbidity study

    Science.gov (United States)

    Crozier, G. F.; Schroeder, W. W.

    1978-01-01

    The termination of studies carried on for almost three years in the Mobile Bay area and adjacent continental shelf are reported. The initial results concentrating on the shelf and lower bay were presented in the interim report. The continued scope of work was designed to attempt a refinement of the mathematical model, assess the effectiveness of optical measurement of suspended particulate material and disseminate the acquired information. The optical characteristics of particulate solutions are affected by density gradients within the medium, density of the suspended particles, particle size, particle shape, particle quality, albedo, and the angle of refracted light. Several of these are discussed in detail.

  20. Richards Bay effluent pipeline

    CSIR Research Space (South Africa)

    Lord, DA

    1986-07-01

    Full Text Available of major concern identified in the effluent are the large volume of byproduct calcium sulphate (phosphogypsum) which would smother marine life, high concentrations of fluoride highly toxic to marine life, heavy metals, chlorinated organic material... ........................ 9 THE RICHARDS BAY PIPELINE ........................................ 16 Environmental considerations ................................... 16 - Phosphogypsum disposal ................................... 16 - Effects of fluoride on locally occurring...

  1. Bayes and Networks

    NARCIS (Netherlands)

    Gao, F.

    2017-01-01

    The dissertation consists of research in three subjects in two themes—Bayes and networks: The first studies the posterior contraction rates for the Dirichlet-Laplace mixtures in a deconvolution setting (Chapter 1). The second subject regards the statistical inference in preferential attachment

  2. Evaluation of input output efficiency of oil field considering undesirable output —A case study of sandstone reservoir in Xinjiang oilfield

    Science.gov (United States)

    Zhang, Shuying; Wu, Xuquan; Li, Deshan; Xu, Yadong; Song, Shulin

    2017-06-01

    Based on the input and output data of sandstone reservoir in Xinjiang oilfield, the SBM-Undesirable model is used to study the technical efficiency of each block. Results show that: the model of SBM-undesirable to evaluate its efficiency and to avoid defects caused by traditional DEA model radial angle, improve the accuracy of the efficiency evaluation. by analyzing the projection of the oil blocks, we find that each block is in the negative external effects of input redundancy and output deficiency benefit and undesirable output, and there are greater differences in the production efficiency of each block; the way to improve the input-output efficiency of oilfield is to optimize the allocation of resources, reduce the undesirable output and increase the expected output.

  3. Sustainable development in the Hudson Bay/James Bay bioregion

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    An overview is presented of projects planned for the James Bay/Hudson Bay region, and the expected environmental impacts of these projects. The watershed of James Bay and Hudson Bay covers well over one third of Canada, from southern Alberta to central Ontario to Baffin Island, as well as parts of north Dakota and Minnesota in the U.S.A. Hydroelectric power developments that change the timing and rate of flow of fresh water may cause changes in the nature and duration of ice cover, habitats of marine mammals, fish and migratory birds, currents into and out of Hudson Bay/James Bay, seasonal and annual loads of sediments and nutrients to marine ecosystems, and anadromous fish populations. Hydroelectric projects are proposed for the region by Quebec, Ontario and Manitoba. In January 1992, the Canadian Arctic Resources Committee (CARC), the Environmental Committee of Sanikuluaq, and the Rawson Academy of Arctic Science will launch the Hudson Bay/James Bay Bioregion Program, an independent initiative to apply an ecosystem approach to the region. Two main objectives are to provide a comprehensive assessment of the cumulative impacts of human activities on the marine and freshwater ecosystems of the Hudson Bay/James Bay bioregion, and to foster sustainable development by examining and proposing cooperative processes for decision making among governments, developers, aboriginal peoples and other stakeholders. 1 fig

  4. Sequence Stratigraphy of lower zones of Asmari Formation in Marun Oilfield by using of microfacies analysis, isolith maps and γ- Ray log

    Directory of Open Access Journals (Sweden)

    Jalil Jafari

    2015-01-01

    Full Text Available The Oligo- Miocene Asmari Formation is one of the most important reservoir units of the Marun Oilfield in Dezful Embayment SW Iran, deposited in Zagros foreland basin. The goal of this study is to interpret depositional environment and sequence stratigraphy of lower zones of the Asmari Formation in Well No.281, 342 and 312in Marun Oilfield based on changes in the shape of γ- Ray, isolith maps and microfacies properties. Accordingly, identification of 9 carbonate microfacies and 2 siliciclastic petrofacies were identified that are deposited in four depositional environment including open marine, barrier, lagoon and tidal flat in a homoclinal ramp (consisting of outer, middle and inner ramp. Also, based on the shape of γ- Ray log, There sediment were deposited in marine environment. In open marine and barrier environments, The shape of γ- Ray log is serrated bell-shaped, serrated funnel-shaped, left bow-shaped, serrated shape and right boxcar shape, Whole in the beach environment it is cylinder and funnel shape and in lagoon and tidal flat environment can be seen on right bow to cylinder-shaped. Based on the isolith maps, sandstone of lower zones of the Asmari Formation in Marun Oilfield expanded by deltaic system along the southwestern margin of the basin and influenced by changes in sea level constantly. Sequence stratigraphic analysis led to identification of three third- order (DS1, DS2 and DS3 depositional sequences.

  5. Sequence Stratigraphy of lower zones of Asmari Formation in Marun Oilfield by using of microfacies analysis, isolith maps and γ- Ray log

    Directory of Open Access Journals (Sweden)

    Ahmad Mirmarghabi

    2015-02-01

    Full Text Available The Oligo- Miocene Asmari Formation is one of the most important reservoir units of the Marun Oilfield in Dezful Embayment SW Iran, deposited in Zagros foreland basin. The goal of this study is to interpret depositional environment and sequence stratigraphy of lower zones of the Asmari Formation in Well No.281, 342 and 312in Marun Oilfield based on changes in the shape of γ- Ray, isolith maps and microfacies properties. Accordingly, identification of 9 carbonate microfacies and 2 siliciclastic petrofacies were identified that are deposited in four depositional environment including open marine, barrier, lagoon and tidal flat in a homoclinal ramp (consisting of outer, middle and inner ramp. Also, based on the shape of γ- Ray log, There sediment were deposited in marine environment. In open marine and barrier environments, The shape of γ- Ray log is serrated bell-shaped, serrated funnel-shaped, left bow-shaped, serrated shape and right boxcar shape, Whole in the beach environment it is cylinder and funnel shape and in lagoon and tidal flat environment can be seen on right bow to cylinder-shaped. Based on the isolith maps, sandstone of lower zones of the Asmari Formation in Marun Oilfield expanded by deltaic system along the southwestern margin of the basin and influenced by changes in sea level constantly. Sequence stratigraphic analysis led to identification of three third- order (DS1, DS2 and DS3 depositional sequences.

  6. Study on the interaction mechanism between the special geological environment and their extreme geo-microbes in Dagang Oilfield by combined methods

    Science.gov (United States)

    Yao, Jun

    2010-05-01

    Geo-microbes and their function were widespread ever since life appeared on the earth. Geo-microbiological process has left a rich and colorful material record in the geological body of earth, the most critical record of which is all sorts of organic hieroglyph and various forms of organic matter derived from bio-organisms, and oil field is the most ideal geological location to preserve these organic matters. It have already produced or might produce petroleum and natural gas sedimentary rocks under natural conditions, also known as olefiant (gas) rock or the parent rock, which is the product of the interaction between the life-system and earth environmental system in the specific geological conditions and integrate the whole microbial ecosystem in the geological time. The microbial community under extreme geological environment of Dagang Oilfield is relatively simple, therefore it is quite easy to investigate the special relationship between geo-microbes and biogeochemistry. We have mastered a large number of information related with the geological condition and biological species of Dagang Oilfield; what's more we also have isolated a number of archimycetes strains with different extremophiles capacity from the core samples collected in the Dagang oil field. At present, we are to proceed with the cooperative research at Environment School of Yale University and Institute of the Earth's biosphere using these strains. In the future, we will work together to carry out geological surveys in the field using international first-class equipment and methods and study the geological environment of Dagang Oilfield utilizing isotope techniques and mineral phase analysis method. Meanwhile we are going to undertake the on-line monitoring of the overall microbial activity of these collected geological samples, the specific metabolic activity of these extreme strains of microorganisms and the biomarkers produced during their metabolic processes under laboratory conditions

  7. BCDC Bay Trail Alignment 2009

    Data.gov (United States)

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

  8. Effects of waste drilling fluid on bacterial isolates from a mangrove swamp oilfield location in the Niger delta of Nigeria

    International Nuclear Information System (INIS)

    Benka-Coker, M.O.; Olumagin, A.

    1996-01-01

    Four bacteria strains isolated from a mangrove swamp oilfield location in the Niger Delta of Nigeria were cultured aerobically in the presence of 1.0% waste drilling fluid, to determine the effect of the waste on their growth. A 2-h lag phase of growth was produced by the waste in cultures of Micrococcus and Pseudomonas species, while the waste increased the lag phases of Alcaligenes and Staphylococcus species to 4 h. The exponential phase of growth of Pseudomonas sp. was depressed by the waste drilling fluid but fluid stimulated the exponential phases of Micrococcus and Alcaligenes spp. There was enhancement of the growth rate of Alcaligenes and Micrococcus spp. while those of Staphylococcus and Pseudonomas spp. were decreased. The depressed growth rates of Staphylococcus and Pseudonomas spp. in the presence of the waste drilling fluid might lead to a decrease in their contribution to the removal of the waste from the environment during spillage or disposal and, therefore, may result in an accumulation of the waste in the environment. (author)

  9. Strontium isotope systematics of mixing groundwater and oil-field brine at Goose Lake in northeastern Montana, USA

    Science.gov (United States)

    Peterman, Zell E.; Thamke, Joanna N.; Futa, Kiyoto; Preston, Todd

    2012-01-01

    Groundwater, surface water, and soil in the Goose Lake oil field in northeastern Montana have been affected by Cl−-rich oil-field brines during long-term petroleum production. Ongoing multidisciplinary geochemical and geophysical studies have identified the degree and local extent of interaction between brine and groundwater. Fourteen samples representing groundwater, surface water, and brine were collected for Sr isotope analyses to evaluate the usefulness of 87Sr/86Sr in detecting small amounts of brine. Differences in Sr concentrations and 87Sr/86Sr are optimal at this site for the experiment. Strontium concentrations range from 0.13 to 36.9 mg/L, and corresponding 87Sr/86Sr values range from 0.71097 to 0.70828. The local brine has 168 mg/L Sr and a 87Sr/86Sr value of 0.70802. Mixing relationships are evident in the data set and illustrate the sensitivity of Sr in detecting small amounts of brine in groundwater. The location of data points on a Sr isotope-concentration plot is readily explained by an evaporation-mixing model. The model is supported by the variation in concentrations of most of the other solutes.

  10. Mapping local singularities using magnetic data to investigate the volcanic rocks of the Qikou depression, Dagang oilfield, eastern China

    Directory of Open Access Journals (Sweden)

    G. Chen

    2013-07-01

    Full Text Available The spatial structural characteristics of geological anomaly, including singularity and self-similarity, can be analysed using fractal or multifractal modelling. Here we apply the multifractal methods to potential fields to demonstrate that singularities can characterise geological bodies, including rock density and magnetic susceptibility. In addition to enhancing weak gravity and magnetic anomalies with respect to either strong or weak background levels, the local singularity index (α ≈ 2 can be used to delineate the edges of geological bodies. Two models were established to evaluate the effectiveness of mapping singularities for extracting weak anomalies and delineating edges of buried geological bodies. The Qikou depression of the Dagang oilfield in eastern China has been chosen as a study area for demonstrating the extraction of weak anomalies of volcanic rocks, using the singularity mapping technique to analyse complex magnetic anomalies caused by complex geological background. The results have shown that the singularities of magnetic data mapped in the paper are associated with buried volcanic rocks, which have been verified by both drilling and seismic survey, and the S–N and E–W faults in the region. The targets delineated for deeply seated faults and volcanic rocks in the Qikou depression should be further investigated for the potential application in undiscovered oil and gas reservoirs exploration.

  11. A unique laboratory test rig reduces the need for offshore tests to combat calcium naphthenate deposition in oilfield process equipment.

    Energy Technology Data Exchange (ETDEWEB)

    Mediaas, Heidi; Grande, Knut; Hustad, Britt-Marie; Hoevik, Kim Reidar; Kummernes, Hege; Nergaard, Bjoern; Vindstad, Jens Emil

    2006-03-15

    Producing and refining high-TAN crude oils introduces a number of challenges, among which calcium naphthenate deposition in process facilities is the most serious production issue. Until recently, the only option for studying chemicals and process parameters in order to prevent naphthenate deposition has been field tests. Statoil has now developed a small scale pilot plant where these experiments can be performed in the laboratory at Statoil's Research and Technology Center in Trondheim, Norway. The results from the pilot plant are in full agreement with the extensive naphthenate experience obtained from almost 9 years operation of the Heidrun oilfield. The design and operational procedures for this test facility are based on the recent discovery by Statoil and ConocoPhillips of the ARN acid. The ARN acid is a prerequisite for calcium naphthenate deposition. The new continuous flow pilot plant, the Naphthenate Rig, is used to develop new environmental friendly naphthenate inhibitors and to optimize process operating conditions. Since it operates on real crudes the need for field tests in qualifying new naphthenate inhibitors is reduced. To the best of our knowledge, the rig is the first of its kind in the world. (Author)

  12. Geochemical investigation of petroleum source rocks by using Rock- Eval data in the Agha-Jari oilfield

    Directory of Open Access Journals (Sweden)

    Behzad khani

    2015-01-01

    Full Text Available In this study, 40 drilling cutting of the Pabdeh, Gurpi, kazhdumi and Gadvan Formations from the Agha-Jari Oilfield were analyzed by using Rock-Eval pyrolysis. In order to recognizing sedimentary environmental conditions of studied Formations, they are divided to 4 zones which A (Kazhdumi Formation#187 and C (Kazhdumi Formation#140 zones show reduction conditions by presence of sea organic materials and B (Gadvan Formation #140 and D(Gadvan Formation#187 zones show oxidation conditions by presence of continental organic materials to basin. Based on the Rock-Eval pyrolysis data, the Pabeh, Gurpi, Kazhdumi and Gadvan Formations have variable hydrocarbon generative potential. HI vs. OI plot revealed that the kerogen type in this Formations is a mixed of types II & III. The intensity of matrix effect in the Pabdeh, Gurpi, Kazhdumi and Gadvan Formations was compared by using S2 vs. TOC plot and calculating its regression equation. The results show that the significant amount of S2 adsorption by matrix was happened in the Pabdeh (4.98-6.96 mg HC/gr rock in wells 113 and 121 and Gurpi Formations ‌(4.33 mg HC/gr rock in well 113 which is due to their low thermal maturity‌(Tmax

  13. Effects of adding bulking agent, inorganic nutrient and microbial inocula on biopile treatment for oil-field drilling waste.

    Science.gov (United States)

    Ma, Jie; Yang, Yongqi; Dai, Xiaoli; Chen, Yetong; Deng, Hanmei; Zhou, Huijun; Guo, Shaohui; Yan, Guangxu

    2016-05-01

    Contamination from oil-field drilling waste is a worldwide environmental problem. This study investigated the performance of four bench-scale biopiles in treating drilling waste: 1) direct biopile (DW), 2) biopile plus oil-degrading microbial consortium (DW + M), 3) biopile plus microbial consortium and bulking agents (saw dust) (DW + M + BA), 4) biopile plus microbial consortium, bulking agents, and inorganic nutrients (Urea and K2HPO4) (DW + M + BA + N). Ninety days of biopiling removed 41.0%, 44.0%, 55.7% and 87.4% of total petroleum hydrocarbon (TPH) in the pile "DW", "DW + M", "DW + M + BA", and "DW + M + BA + N" respectively. Addition of inorganic nutrient and bulking agents resulted in a 56.9% and 26.6% increase in TPH removal efficiency respectively. In contrast, inoculation of hydrocarbon-degrading microorganisms only slightly enhanced the contaminant removal (increased 7.3%). The biopile with stronger contaminant removal also had higher pile temperature and lower pile pH (e.g., in "DW + M + BA + N"). GC-MS analysis shows that biopiling significantly reduced the total number of detected contaminants and changed the chemical composition. Overall, this study shows that biopiling is an effective remediation technology for drilling waste. Adding inorganic nutrients and bulking agents can significantly improve biopile performance while addition of microbial inocula had minimal positive impacts on contaminant removal. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Effects of waste drilling fluid on bacterial isolates from a mangrove swamp oilfield location in the Niger delta of Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Benka-Coker, M.O.; Olumagin, A. [Benin Univ. (Nigeria). Dept. of Microbiology

    1996-03-01

    Four bacteria strains isolated from a mangrove swamp oilfield location in the Niger Delta of Nigeria were cultured aerobically in the presence of 1.0% waste drilling fluid, to determine the effect of the waste on their growth. A 2-h lag phase of growth was produced by the waste in cultures of Micrococcus and Pseudomonas species, while the waste increased the lag phases of Alcaligenes and Staphylococcus species to 4 h. The exponential phase of growth of Pseudomonas sp. was depressed by the waste drilling fluid but fluid stimulated the exponential phases of Micrococcus and Alcaligenes spp. There was enhancement of the growth rate of Alcaligenes and Micrococcus spp. while those of Staphylococcus and Pseudonomas spp. were decreased. The depressed growth rates of Staphylococcus and Pseudonomas spp. in the presence of the waste drilling fluid might lead to a decrease in their contribution to the removal of the waste from the environment during spillage or disposal and, therefore, may result in an accumulation of the waste in the environment. (author)

  15. Impact of stylolitization on diagenesis of a Lower Cretaceous carbonate reservoir from a giant oilfield, Abu Dhabi, United Arab Emirates

    Science.gov (United States)

    Paganoni, Matteo; Al Harthi, Amena; Morad, Daniel; Morad, Sadoon; Ceriani, Andrea; Mansurbeg, Howri; Al Suwaidi, Aisha; Al-Aasm, Ihsan S.; Ehrenberg, Stephen N.; Sirat, Manhal

    2016-04-01

    Bed-parallel stylolites are a widespread diagenetic feature in Lower Cretaceous limestone reservoirs, Abu Dhabi, United Arab Emirates (UAE). Diagenetic calcite, dolomite, kaolin and small amounts of pyrite, fluorite, anhydrite and sphalerite occur along and in the vicinity of the stylolites. Petrographic observations, negative δ18OVPDB, fluid inclusion microthermometry, and enrichment in 87Sr suggest that these cements have precipitated from hot basinal brines, which migrated along the stylolites and genetically related microfractures (tension gashes). Fluid migration was presumably related to lateral tectonic compression events related to the foreland basin formation. The low solubility of Al3 + in formation waters suggests that kaolin precipitation was linked to derivation of organic acids during organic matter maturation, probably in siliciclastic source rocks. The mass released from stylolitization was presumably re-precipitated as macro- and microcrystalline calcite cement in the host limestones. The flanks of the oilfield (water zone) display more frequent presence and higher amplitude of stylolites, lower porosity and permeability, higher homogenization temperatures and more radiogenic composition of carbonates compared to the crest (oil zone). This indicates that oil emplacement retards diagenesis. This study demonstrates that stylolitization plays a crucial role in fluid flow and diagenesis of carbonate reservoirs during basin evolution.

  16. Evaluation of stability and viscosity measurement of emulsion from oil from production in northern oilfield in Thailand

    Science.gov (United States)

    Juntarasakul, O.; Maneeintr, K.

    2018-04-01

    Emulsion is normally present in oil due to the mixing occurring during oil recovery. The formation of emulsion can cause some problems in production and transportation. Viscosity and stability of emulsion play a key roles in oil transportation and separation to meet sales specification. Therefore, the aims of this research are to measure the viscosity of oil an emulsion and to evaluate the stability of emulsion of light oil from Fang oilfield in Thailand. The parameters of this study are temperature, shear rate and water cut ranging from 50 to 80 °C, 3.75 to 70 s-1 and 0 to 60%, respectively. These effects of parameters on viscosity and stability of emulsion are required for the design of the process and to increase oil production with various conditions. The results shows that viscosity decreases as temperature and shear rate increase. In contrast, viscosity becomes higher when water cut is lower. Furthermore, droplet sizes of water-in-oil emulsion at different conditions are investigated the stability of emulsion. The droplet sizes become smaller when high shear rate is applied and emulsion becomes more stable. Furthermore, correlations are developed to predict the viscosity and stability of the oil and emulsion from Thailand.

  17. [Phylogenetic diversity and activity of anaerobic microorganisms of high-temperature horizons of the Dagang Oilfield (China)].

    Science.gov (United States)

    Nazina, T N; Shestakova, N M; Grigor'ian, A A; Mikhaĭlova, E M; Turova, T P; Poltaraus, A B; Feng, C; Ni, F; Beliaev, S S

    2006-01-01

    The number of microorganisms of major metabolic groups and the rates of sulfate-reducing and methanogenic processes in the formation waters of the high-temperature horizons of Dagang oilfield have been determined. Using cultural methods, it was shown that the microbial community contained aerobic bacteria oxidizing crude oil, anaerobic fermentative bacteria, sulfate-reducing bacteria, and methanogenic bacteria. Using cultural methods, the possibility of methane production from a mixture of hydrogen and carbon dioxide (H2 + CO2) and from acetate was established, and this result was confirmed by radioassays involving NaH14CO3 and 14CH3COONa. Analysis of 16S rDNA of enrichment cultures of methanogens demonstrated that these microorganisms belong to Methanothermobacter sp. (M. thermoautotrophicus), which consumes hydrogen and carbon dioxide as basic substrates. The genes of acetate-utilizing bacteria were not identified. Phylotypes of the representatives of Thermococcus spp. were found among 16S rDNAs of archaea. 16S rRNA genes of bacterial clones belong to the orders Thermoanaerobacteriales (Thermoanaerobacter, Thermovenabulum, Thermacetogenium, and Coprothermobacter spp.), Thermotogales, Nitrospirales (Thermodesulfovibrio sp.) and Planctomycetales. 16S rDNA of a bacterium capable of oxidizing acetate in the course of syntrophic growth with H2-utilizing methanogens was found at high-temperature petroleum reservoirs for the first time. These results provide further insight into the composition of microbial communities of high-temperature petroleum reservoirs, indicating that syntrophic processes play an important part in acetate degradation accompanied by methane production.

  18. Distribution of petroleum degrading genes and factor analysis of petroleum contaminated soil from the Dagang Oilfield, China

    Science.gov (United States)

    Liu, Qinglong; Tang, Jingchun; Bai, Zhihui; Hecker, Markus; Giesy, John P.

    2015-01-01

    Genes that encode for enzymes that can degrade petroleum hydrocarbons (PHs) are critical for the ability of microorganisms to bioremediate soils contaminated with PHs. Distributions of two petroleum-degrading genes AlkB and Nah in soils collected from three zones of the Dagang Oilfield, Tianjin, China were investigated. Numbers of copies of AlkB ranged between 9.1 × 105 and 1.9 × 107 copies/g dry mass (dm) soil, and were positively correlated with total concentrations of PHs (TPH) (R2 = 0.573, p = 0.032) and alkanes (C33 ~ C40) (R2 = 0.914, p < 0.01). The Nah gene was distributed relatively evenly among sampling zones, ranging between 1.9 × 107 and 1.1 × 108 copies/g dm soil, and was negatively correlated with concentrations of total aromatic hydrocarbons (TAH) (R2 = −0.567, p = 0.035) and ∑16 PAHs (R2 = −0.599, p = 0.023). Results of a factor analysis showed that individual samples of soils were not ordinated as a function of the zones. PMID:26086670

  19. 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.

  20. Static reservoir modeling of the Bahariya reservoirs for the oilfields development in South Umbarka area, Western Desert, Egypt

    Science.gov (United States)

    Abdel-Fattah, Mohamed I.; Metwalli, Farouk I.; Mesilhi, El Sayed I.

    2018-02-01

    3D static reservoir modeling of the Bahariya reservoirs using seismic and wells data can be a relevant part of an overall strategy for the oilfields development in South Umbarka area (Western Desert, Egypt). The seismic data is used to build the 3D grid, including fault sticks for the fault modeling, and horizon interpretations and surfaces for horizon modeling. The 3D grid is the digital representation of the structural geology of Bahariya Formation. When we got a reasonably accurate representation, we fill the 3D grid with facies and petrophysical properties to simulate it, to gain a more precise understanding of the reservoir properties behavior. Sequential Indicator Simulation (SIS) and Sequential Gaussian Simulation (SGS) techniques are the stochastic algorithms used to spatially distribute discrete reservoir properties (facies) and continuous reservoir properties (shale volume, porosity, and water saturation) respectively within the created 3D grid throughout property modeling. The structural model of Bahariya Formation exhibits the trapping mechanism which is a fault assisted anticlinal closure trending NW-SE. This major fault breaks the reservoirs into two major fault blocks (North Block and South Block). Petrophysical models classified Lower Bahariya reservoir as a moderate to good reservoir rather than Upper Bahariya reservoir in terms of facies, with good porosity and permeability, low water saturation, and moderate net to gross. The Original Oil In Place (OOIP) values of modeled Bahariya reservoirs show hydrocarbon accumulation in economic quantity, considering the high structural dips at the central part of South Umbarka area. The powerful of 3D static modeling technique has provided a considerable insight into the future prediction of Bahariya reservoirs performance and production behavior.

  1. Oilfield water treatment by electrocoagulation-reverse osmosis for agricultural use: effects on germination and early growth characteristics of sunflower.

    Science.gov (United States)

    de Souza, Paulo S A; Cerqueira, Alexandre A; Rigo, Michelle M; de Paiva, Julieta L; Couto, Rafael S P; Merçon, Fábio; Perez, Daniel V; Marques, Monica R C

    2017-05-01

    This study aims to evaluate the effects of oilfield water (OW), treated by a hybrid process of electrocoagulation and reverse osmosis (EC-RO), on seed germination and early growth characteristics of sunflower (Heliantus annus L.). In the EC step, tests were conducted with 28.6 A m -2 current density and 4 min. reaction time. In the RO step, the system was operated with 1 L min -1 constant flow and 2 MPa, 2.5 MPa and 3 MPa feed pressures. In all feed pressures, RO polymeric membranes achieved very high removals of chemical oxygen demand (up to 89%) and oils and greases (100%) from EC-treated effluent. In best feed pressure (2.5 MPa), turbidity, total dissolved salts, electrical conductivity, salinity, toxic ions and sodium adsorption ratio values attained internationally recognized standards for irrigation water. Using EC-RO (feed pressure:2.5 MPa) treated OW, germinated sunflower seeds percentage (86 ± 6%), speed of germination (30 ± 2) and biomass production (49 ± 5 mg) were statistically similar to control (distilled water) results. Vigor index average values obtained using OW treated by EC-RO (3871)were higher than that obtained by OW water treated by EC (3300). The results of this study indicate that EC-RO seems to be a promising alternative for treatment of OW aiming sunflower crops irrigation, since the use of this treated effluent did not affect adversely seed germination and seedling development, and improved seedling vigor. Furthermore, OW treatment by EC-RO reduces sodium levels into acceptable standards values avoiding soil degradation.

  2. Oil pollution in the Red Sea - Environmental monitoring of an oilfield in a Coral area, Gulf of Suez

    Energy Technology Data Exchange (ETDEWEB)

    Dicks, B

    1984-01-01

    The Red Sea is rapidly developing as one of the world's largest offshore oil production areas. It also comprises a wide range of tropical marine habitats, many of which are internationally recognised for their conservation, scientific, economic or recreational value. Past oil production, refining and transport have resulted in chronic pollution of some areas, and environmental programmes to protect new areas of development from pollution damage are assuming increasing importance. At the initiative of an Egyptian oil company operating in the Gulf of Suez, an environmental protection and management scheme has been prepared for a new offshore oilfield and marine terminal at Ras Budran. This paper describes the form of the scheme and the results of its component environmental surveys. The development area comprises rich and diverse marine communities of fringing coral reefs, nearshore lagoons, seagrass beds, sandy beaches and fine sediments offshore. A baseline survey was designed following detailed discussion of the scope of the development with the company and a preliminary site visit, and the fieldwork was completed in October 1980. On the basis of the findings of the survey, a series of recommendations was made to the company, aimed at reducing environmental impacts during construction and operation to a minimum and acceptable level. These were subsequently implemented and the results of a post-construction survey in February 1983 are reported which show that environmental damage to the nearshore habitats during the construction phase had been relatively small and localised. Recently, the biological information obtained from the two surveys has also been incorporated into oil spill contingency plans.

  3. Bay of Fundy

    Science.gov (United States)

    2006-01-01

    The highest tides on Earth occur in the Minas Basin, the eastern extremity of the Bay of Fundy, Nova Scotia, Canada, where the tide range can reach 16 meters when the various factors affecting the tides are in phase. The primary cause of the immense tides of Fundy is a resonance of the Bay of Fundy-Gulf of Maine system. The system is effectively bounded at this outer end by the edge of the continental shelf with its approximately 40:1 increase in depth. The system has a natural period of approximately 13 hours, which is close to the 12h25m period of the dominant lunar tide of the Atlantic Ocean. Like a father pushing his daughter on a swing, the gentle Atlantic tidal pulse pushes the waters of the Bay of Fundy-Gulf of Maine basin at nearly the optimum frequency to cause a large to-and-fro oscillation. The greatest slosh occurs at the head (northeast end) of the system. The high tide image (top) was acquired April 20, 2001, and the low tide image (bottom) was acquired September 30, 2002. The images cover an area of 16.5 by 21 km, and are centered near 64 degrees west longitude and 45.5 degrees north latitude. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and the data products. The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping, and monitoring of dynamic conditions and temporal change. Example applications are: monitoring glacial advances and retreats; monitoring potentially active volcanoes; identifying

  4. USGS Tampa Bay Pilot Study

    Science.gov (United States)

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

    2007-01-01

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

  5. [Prospective cohort study on the occupational stress and mental disorder among the oilfield workers in Xinjiang Autonomous Region in 2013-2015].

    Science.gov (United States)

    Han, Rui; Shi, Haohua; Chen, Yulu; Lian, Yulong; Liu, Jiwen

    2018-01-01

    To explore the relationship between occupational stress and psychological disorder among oilfield workers. In 2013, 1485 psychological normal oilfield workers using the stratified cluster sampling in Xinjiang Autonomous Region were investigated, and the follow-up was conducted in 2015. Occupational stress and mental health status were assessed by questionnaire for the occupation stress and self-rating symptom. The people with mental disorder was 556, the incidence rate was40. 29%. The level of occupational stress level low-high group( RR = 2. 689, 95% CI1. 342-5. 391) and middle-high group( RR = 2. 878, 95% CI 1. 205-6. 875) of mental disorder were higher than the low-low group, the level of Personal Strain Questionnaire low-middle group( RR = 2. 500, 95% CI 1. 700-3. 763) and low-high group( RR =3. 907, 95% CI 1. 955-7. 651) and middle-middle group( RR = 2. 141, 95% CI 1. 016-4. 512) of mental disorder were higher than low-low group. Without drinking( RR =0. 779, 95% CI = 0. 622-0. 976) was protective factor for mental disorders. Occupational stress and drinking are the risk factors of mental disorder, it is more practical to multiple measurement of the psychological disorder of occupational stress exposure than single one.

  6. The Simulation of Temperature Field Based on 3D Modeling and Its Comparison versus Measured Temperature Distribution of Daqing Oilfield, NE China

    Science.gov (United States)

    Shi, Y.; Jiang, G.; Hu, S.

    2017-12-01

    Daqing, as the largest oil field of China with more than 50 years of exploration and production history for oil and gas, its geothermal energy utilization was started in 2000, with a main focus on district heating and direct use. In our ongoing study, data from multiple sources are collected, including BHT, DST, steady state temperature measurements in deep wells and thermophysical properties of formations. Based on these measurements, an elaborate investigation of the temperature field of Daqing Oilfield is made. Moreover, through exploration for oil and gas, subsurface geometry, depth, thickness and properties of the stratigraphic layers have been extensively delineated by well logs and seismic profiles. A 3D model of the study area is developed incorporating the information of structure, stratigraphy, basal heat flow, and petrophysical and thermophysical properties of strata. Based on the model, a simulation of the temperature field of Daqing Oilfield is generated. A purely conductive regime is presumed, as demonstrated by measured temperature log in deep wells. Wells W1, W2 and SK2 are used as key wells for model calibration. Among them, SK2, as part of the International Continental Deep Drilling Program, has a designed depth of 6400m, the steady state temperature measurement in the borehole has reached the depth of 4000m. The results of temperature distribution generated from simulation and investigation are compared, in order to evaluate the potential of applying the method to other sedimentary basins with limited borehole temperature measurements but available structural, stratigraphic and thermal regime information.

  7. Organic geochemistry investigations of crude oils from Bayoot oilfield in the Masila Basin, east Yemen and their implication for origin of organic matter and source-related type

    Directory of Open Access Journals (Sweden)

    Mohammed Hail Hakimi

    2018-03-01

    Full Text Available Thirteen crude oil samples from fractured basement reservoir rocks in the Bayoot oilfield, Masila Basin were studied to describe oil characteristics and to provide information on the source of organic matter input and the genetic link between oils and their potential source rock in the basin. The bulk geochemical results of whole oil and gasoline hydrocarbons indicate that the Bayoot oils are normal crude oil, with high hydrocarbons of more than 60%. The hydrocarbons are dominated by normal, branched and cyclic alkanes a substantial of the light aromatic compounds, suggesting aliphatic oil-prone kerogen. The high abundant of normal, branched and cyclic alkanes also indicate that the Bayoot oils are not biodegradation oils.The biomarker distributions of isoprenoid, hopane, aromatic and sterane and their cross and triangular plots suggest that the Bayoot oils are grouped into one genetic family and were generated from marine clay-rich source rock that received mixed organic matter and deposited under suboxic conditions. The biomarker distributions of the Bayoot oils are consistent with those of the Late Jurassic Madbi source rock in the basin. Biomarker maturity and oil compositions data also indicate that the Bayoot oils were generated from mature source rock with peak oil-window maturity. Keywords: Crude oil, Basement reservoir rocks, Biomarker, Organic source input, Bayoot oilfield, Masila Basin

  8. Anomalies of natural gas compositions and carbon isotope ratios caused by gas diffusion - A case from the Donghe Sandstone reservoir in the Hadexun Oilfield, Tarim Basin, northwest China

    Science.gov (United States)

    Wang, Yangyang; Chen, Jianfa; Pang, Xiongqi; Zhang, Baoshou; Wang, Yifan; He, Liwen; Chen, Zeya; Zhang, Guoqiang

    2018-05-01

    Natural gases in the Carboniferous Donghe Sandstone reservoir within the Block HD4 of the Hadexun Oilfield, Tarim Basin are characterized by abnormally low total hydrocarbon gas contents ( δ13C ethane (C2) gas has never been reported previously in the Tarim Basin and such large variations in δ13C have rarely been observed in other basins globally. Based on a comprehensive analysis of gas geochemical data and the geological setting of the Carboniferous reservoirs in the Hadexun Oilfield, we reveal that the anomalies of the gas compositions and carbon isotope ratios in the Donghe Sandstone reservoir are caused by gas diffusion through the poorly-sealed caprock rather than by pathways such as gas mixing, microorganism degradation, different kerogen types or thermal maturity degrees of source rocks. The documentation of an in-reservoir gas diffusion during the post entrapment process as a major cause for gas geochemical anomalies may offer important insight into exploring natural gas resources in deeply buried sedimentary basins.

  9. 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...

  10. 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...

  11. Recent results from Daya Bay

    Directory of Open Access Journals (Sweden)

    Chua Ming-chung

    2016-01-01

    Full Text Available Utilizing powerful nuclear reactors as antineutrino sources, high mountains to provide ample shielding from cosmic rays in the vicinity, and functionally identical detectors with large target volume for near-far relative measurement, the Daya Bay Reactor Neutrino Experiment has achieved unprecedented precision in measuring the neutrino mixing angle θ13 and the neutrino mass squared difference |Δm2ee|. I will report the latest Daya Bay results on neutrino oscillations and light sterile neutrino search.

  12. Experimental Analysis of Soil and Mandarin Orange Plants Treated with Heavy Metals Found in Oilfield-Produced Wastewater

    Directory of Open Access Journals (Sweden)

    Ailin Zhang

    2018-05-01

    Full Text Available Despite a declining trend, California remains a significant oil-producing state. For every barrel of crude oil, an average of 15 barrels of oilfield produced water (OPW is generated, some of which is used to boost freshwater sources for crop irrigation in the agriculturally important Central Valley. OPW is known to contain salts, metals, hydrocarbons, alkylphenols, naturally radioactive materials, biocides, and other compounds from drilling and production processes. Less is known about the potential uptake and accumulation of these compounds in crops and soil irrigated with OPW. In this study, 23 potted mandarin orange plants were irrigated two to three times weekly (depending on season with water containing three different concentrations of the known OPW heavy metals barium, chromium, lead, and silver. Seven sets of samples of soil and leaves and 11 fruits were collected and processed using microwave-assisted digestion (EPA Method 3051A. Processed samples were analyzed using inductively coupled plasma-optical emission spectroscopy (ICP-OES. Analysis of variance (ANOVA and covariance (ANCOVA coupled with Tukey’s honest significant difference test were used to examine the effects of metal concentrations in the irrigation water and number of watering days, respectively, on the metal concentrations in the soil, leaf, and fruit samples. Accumulation of barium in soil and leaves was strongly positively associated with sample and number of watering days, increasing nearly 2000-fold. Lead also showed an upward trend, increasing up to 560-fold over the baseline level. Total chromium showed an increase in the soil that tapered off, but less consistent results in the leaves and fruit. The silver results were more volatile, but also indicated at least some level of accumulation in the tested media. The smallest absolute accumulation was observed for chromium. Concentrations in the fruit were highest in the peel, followed by pith and juice. Accumulation

  13. EMISSION MEASUREMENTS OF GEOGENIC GREENHOUSE GASES IN THE AREA OF "PUSTY LAS" ABANDONED OILFIELD (POLISH OUTER CARPATHIANS

    Directory of Open Access Journals (Sweden)

    Piotr Guzy

    2017-07-01

    Full Text Available The emission of geogenic methane and carbon dioxide contributes to the world climate changes. The results of studies run worldwide demonstrate that the emission of geogenic gases strongly influences the increasing concentrations of greenhouse gases in the atmosphere, including methane and carbon dioxide. The Outer Carpathians reveal significant hydrocarbon potential and host numerous macro- and microseepages of hydrocarbons including the natural gas. Migration of hydrocarbons from deep accumulations towards the surface is controlled by diffusion and effusion. It appears that the Carpathians may play significant role as a supplier of greenhouse gases to the atmosphere.Before the World War II, oil macroseepages were the principal premises in petroleum exploration. In the Carpathians, hydrocarbons have been exploited since the XIX century. Unfortunately, most of discovered oil and gas deposits are recently only the historical objects. An example is the Sękowa-Ropica Górna-Siary oil deposit located in the marginal part of the Magura Nappe where oil has been extracted with dug wells until the mid XX century. One of such extraction sites is the "Pusty Las" oilfield. In that area, 10 methane and carbon dioxide emission measurement sites were located, among which 4 in dried dug wells and 6 in dig wells still filled with oil and/or water. Dynamics of methane and carbon dioxide concentration changes were measured with the modified static chambers method. Gas samples were collected immediately after the installation of the chamber and again, after 5 and 10 minutes. In the case of reclaimed or dry dug wells, static chamber was installed directly at the ground surface. In wells still filled with oil and/or water the chamber was equipped with an "apron" mounted on special sticks.The dynamics of concentrations changes varied from -0.871 to 119.924 ppm∙min-1 for methane and from -0.005 to 0.053 %obj∙min-1 for carbon dioxide. Average methane emission was 1

  14. Kinetics of oil-cracking for different types of marine oils from Tahe Oilfield, Tarim Basin, NW China

    Directory of Open Access Journals (Sweden)

    Anlai Ma

    2016-02-01

    Full Text Available The C1–C5 gas and carbon isotope ratios generated during the cracking of heavy, normal and high-waxy marine oils from Tahe Oilfield, Tarim Basin, NW China, using a closed-gold tube system under high pressure were presented. The three types of oil tested resulted in a similar gas-generation process. The C2–C5 range initially increased its yield with the application of pyrolysis temperature and thereafter decreased, while the C1 yield increased with the same application. High-waxy oil had the highest C1–C5 yield of 510 mg/goil, whereas heavy oil had the lowest C1–C5 yield of 316 mg/goil. The δ13C1 value was low at first, but gradually became higher as the pyrolysis temperature increased. However, the δ13C2 and δ13C3 values gradually became higher when the temperature was greater than 420 °C. The kinetic parameters of the C1–C5 gas generation for the different types of marine oils were then calculated using KINETIC software. This calculation resulted in a frequency factor of about 1.78 × 1014 s−1, while the distribution of the activation energy of the C1–C5 gas mass generated was relatively narrow with a range from 56 to 66 kcal/mol. Among the three types of oil tested, heavy oil had the widest activation energy distribution and the lowest major frequency of activation energy. The maximum temperature at which oil could be preserved as a separate oil phase varied from about 178 °C at a slow geological heating rate to 206 °C at a fast geological heating rate. This result is based on the kinetic parameters determined and in combination with the fractional conversion (C of oil to gas. Testing conducted at the volatile Middle Cambrian reservoir of well Zhongshen 1 in the Tazhong Uplift strongly supported this conclusion.

  15. 33 CFR 100.919 - International Bay City River Roar, Bay City, MI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false International Bay City River Roar, Bay City, MI. 100.919 Section 100.919 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Bay City River Roar, Bay City, MI. (a) Regulated Area. A regulated area is established to include all...

  16. 77 FR 2972 - Thunder Bay Power Company, Thunder Bay Power, LLC, et al.

    Science.gov (United States)

    2012-01-20

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Thunder Bay Power Company, Thunder Bay Power, LLC, et al.; Notice of Application for Transfer of Licenses, and Soliciting Comments and Motions To Intervene Thunder Bay Power Company Project No. 2404-095 Thunder Bay Power, LLC Midwest Hydro, Inc...

  17. 33 CFR 162.125 - Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc. 162.125 Section 162.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY INLAND WATERWAYS NAVIGATION REGULATIONS § 162.125 Sturgeon Bay and the Sturgeon Bay Ship...

  18. 77 FR 38488 - Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY

    Science.gov (United States)

    2012-06-28

    ... 1625-AA00 Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY... restrict vessels from a portion of the St. Lawrence River during the Alexandria Bay Chamber of Commerce... of proposed rulemaking (NPRM) entitled Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence...

  19. 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...

  20. Humboldt Bay Benthic Habitats 2009 Aquatic Setting

    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...

  1. San Francisco Bay Water Quality Improvement Fund

    Science.gov (United States)

    EPAs grant program to protect and restore San Francisco Bay. The San Francisco Bay Water Quality Improvement Fund (SFBWQIF) has invested in 58 projects along with 70 partners contributing to restore wetlands, water quality, and reduce polluted runoff.,

  2. South Bay Salt Pond Mercury Studies Project

    Science.gov (United States)

    Information about the SFBWQP South Bay Salt Pond Mercury Studies Project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  3. Humboldt Bay, California Benthic Habitats 2009 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  4. Humboldt Bay, California Benthic Habitats 2009 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

  5. Contaminant transport in Massachusetts Bay

    Science.gov (United States)

    Butman, Bradford

    Construction of a new treatment plant and outfall to clean up Boston Harbor is currently one of the world's largest public works projects, costing about $4 billion. There is concern about the long-term impact of contaminants on Massachusetts Bay and adjacent Gulf of Maine because these areas are used extensively for transportation, recreation, fishing, and tourism, as well as waste disposal. Public concern also focuses on Stellwagen Bank, located on the eastern side of Massachusetts Bay, which is an important habitat for endangered whales. Contaminants reach Massachusetts Bay not only from Boston Harbor, but from other coastal communities on the Gulf of Maine, as well as from the atmosphere. Knowledge of the pathways, mechanisms, and rates at which pollutants are transported throughout these coastal environments is needed to address a wide range of management questions.

  6. 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...

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

    International Nuclear Information System (INIS)

    Honda, Teruyuki; Kimura, Ken-ichiro

    2003-01-01

    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 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∼10 cm in depth) from Funka Bay was calculated at approximately 1940∼50, which agreed with the time, 1943∼45 when Showa-shinzan was formed by the eruption of the Usu volcano. (author)

  8. Mobile Bay turbidity plume study

    Science.gov (United States)

    Crozier, G. F.

    1976-01-01

    Laboratory and field transmissometer studies on the effect of suspended particulate material upon the appearance of water are reported. Quantitative correlations were developed between remotely sensed image density, optical sea truth data, and actual sediment load. Evaluation of satellite image sea truth data for an offshore plume projects contours of transmissivity for two different tidal phases. Data clearly demonstrate the speed of change and movement of the optical plume for water patterns associated with the mouth of Mobile bay in which relatively clear Gulf of Mexico water enters the bay on the eastern side. Data show that wind stress in excess of 15 knots has a marked impact in producing suspended sediment loads.

  9. Automation in tube finishing bay

    International Nuclear Information System (INIS)

    Bhatnagar, Prateek; Satyadev, B.; Raghuraman, S.; Syama Sundara Rao, B.

    1997-01-01

    Automation concept in tube finishing bay, introduced after the final pass annealing of PHWR tubes resulted in integration of number of sub-systems in synchronisation with each other to produce final cut fuel tubes of specified length, tube finish etc. The tube finishing bay which was physically segregated into four distinct areas: 1. tube spreader and stacking area, 2. I.D. sand blasting area, 3. end conditioning, wad blowing, end capping and O.D. wet grinding area, 4. tube inspection, tube cutting and stacking area has been studied

  10. Multi-criteria decision making development of ion chromatographic method for determination of inorganic anions in oilfield waters based on artificial neural networks retention model.

    Science.gov (United States)

    Stefanović, Stefica Cerjan; Bolanča, Tomislav; Luša, Melita; Ukić, Sime; Rogošić, Marko

    2012-02-24

    This paper describes the development of ad hoc methodology for determination of inorganic anions in oilfield water, since their composition often significantly differs from the average (concentration of components and/or matrix). Therefore, fast and reliable method development has to be performed in order to ensure the monitoring of desired properties under new conditions. The method development was based on computer assisted multi-criteria decision making strategy. The used criteria were: maximal value of objective functions used, maximal robustness of the separation method, minimal analysis time, and maximal retention distance between two nearest components. Artificial neural networks were used for modeling of anion retention. The reliability of developed method was extensively tested by the validation of performance characteristics. Based on validation results, the developed method shows satisfactory performance characteristics, proving the successful application of computer assisted methodology in the described case study. Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Thou should not know too much. When lack of information promotes co-operative behaviour. The case of oil-fields in Wyoming, Oklahoma and Texas

    Energy Technology Data Exchange (ETDEWEB)

    Hassler, B

    1998-12-31

    Proper assumptions of information levels are of vital importance in all kinds of analysis of interdependent decision-making. In most cases the rule is; the more information the better. In this paper, however, it is shown that such is not always the case. Lack of information can enhance resource utilisation of resources, when the problem of co-operation is of a Prisoner`s dilemma type, and when iteration of the interaction game is unlikely. The case of oil-fields in the United States has been chosen as an empirical example of the latter. Optimal drilling procedures tend to be chosen more often the less the drillers know about the resource characteristics. This outcome is explained by the structure of the decision-making problem, where low levels of information render it advantageous to choose co-operative strategies 16 refs, 4 figs

  12. Thou should not know too much. When lack of information promotes co-operative behaviour. The case of oil-fields in Wyoming, Oklahoma and Texas

    Energy Technology Data Exchange (ETDEWEB)

    Hassler, B.

    1997-12-31

    Proper assumptions of information levels are of vital importance in all kinds of analysis of interdependent decision-making. In most cases the rule is; the more information the better. In this paper, however, it is shown that such is not always the case. Lack of information can enhance resource utilisation of resources, when the problem of co-operation is of a Prisoner`s dilemma type, and when iteration of the interaction game is unlikely. The case of oil-fields in the United States has been chosen as an empirical example of the latter. Optimal drilling procedures tend to be chosen more often the less the drillers know about the resource characteristics. This outcome is explained by the structure of the decision-making problem, where low levels of information render it advantageous to choose co-operative strategies 16 refs, 4 figs

  13. Chesapeake Bay plume dynamics from LANDSAT

    Science.gov (United States)

    Munday, J. C., Jr.; Fedosh, M. S.

    1981-01-01

    LANDSAT images with enhancement and density slicing show that the Chesapeake Bay plume usually frequents the Virginia coast south of the Bay mouth. Southwestern (compared to northern) winds spread the plume easterly over a large area. Ebb tide images (compared to flood tide images) show a more dispersed plume. Flooding waters produce high turbidity levels over the shallow northern portion of the Bay mouth.

  14. Default Bayes factors for ANOVA designs

    NARCIS (Netherlands)

    Rouder, Jeffrey N.; Morey, Richard D.; Speckman, Paul L.; Province, Jordan M.

    2012-01-01

    Bayes factors have been advocated as superior to p-values for assessing statistical evidence in data. Despite the advantages of Bayes factors and the drawbacks of p-values, inference by p-values is still nearly ubiquitous. One impediment to the adoption of Bayes factors is a lack of practical

  15. Managing oilfield data management

    Energy Technology Data Exchange (ETDEWEB)

    Balough, Steve [Vastar Resources, Houston, TX (United States); Betts, Peter [Shell Internationale Petroleum Maatschappij BV, The Hague (Netherlands); Breig, Jack; Karcher, Bruno [Petrotechnical Open Software Corporation POSC, Houston, TX (United States); Erlich, Andre [GeoQuest, Corte Madera, CA (United States); Green, Jim [Unocal Energy Resources Division, Sugar Land, TX (United States); Haines, Paul; Landgren, Ken; Marsden, Rich; Smith, Dwight [GeoQuest, Houston, TX (United States); Pohlman, John [Pohlman and Associates, Inc., Houston, TX (United States); Shields, R Wade [Mobil Exploration and Producing Technical Center, Dallas, TX (United States); Winczewski, Laramie [Fourth Wave Group, Inc., Houston, TX (United States)

    1994-07-01

    Low oil prices and a shrinking pool of internal talent are compelling oil companies to rethink how they manage exploration and production (E+P) data. The idea of a single data store is yielding to a three-level model of data storage: the master, project and application levels. In-house, proprietary software is giving way to third-party packages based on maturing industry standards. Limited access to data is shifting toward free access to any geoscientist. In this article a report and two case studies on how these trends affect geoscientists are given. 16 figs., 2 ills., 20 refs.

  16. Managing oilfield data management

    International Nuclear Information System (INIS)

    Balough, Steve; Betts, Peter; Breig, Jack; Karcher, Bruno; Erlich, Andre; Green, Jim; Haines, Paul; Landgren, Ken; Marsden, Rich; Smith, Dwight; Pohlman, John; Shields, R. Wade; Winczewski, Laramie

    1994-01-01

    Low oil prices and a shrinking pool of internal talent are compelling oil companies to rethink how they manage exploration and production (E+P) data. The idea of a single data store is yielding to a three-level model of data storage: the master, project and application levels. In-house, proprietary software is giving way to third-party packages based on maturing industry standards. Limited access to data is shifting toward free access to any geoscientist. In this article a report and two case studies on how these trends affect geoscientists are given. 16 figs., 2 ills., 20 refs

  17. Helicopter Based Magnetic Detection Of Wells At The Teapot Dome (Naval Petroleum Reserve No. 3 Oilfield: Rapid And Accurate Geophysical Algorithms For Locating Wells

    Science.gov (United States)

    Harbert, W.; Hammack, R.; Veloski, G.; Hodge, G.

    2011-12-01

    In this study Airborne magnetic data was collected by Fugro Airborne Surveys from a helicopter platform (Figure 1) using the Midas II system over the 39 km2 NPR3 (Naval Petroleum Reserve No. 3) oilfield in east-central Wyoming. The Midas II system employs two Scintrex CS-2 cesium vapor magnetometers on opposite ends of a transversely mounted, 13.4-m long horizontal boom located amidships (Fig. 1). Each magnetic sensor had an in-flight sensitivity of 0.01 nT. Real time compensation of the magnetic data for magnetic noise induced by maneuvering of the aircraft was accomplished using two fluxgate magnetometers mounted just inboard of the cesium sensors. The total area surveyed was 40.5 km2 (NPR3) near Casper, Wyoming. The purpose of the survey was to accurately locate wells that had been drilled there during more than 90 years of continuous oilfield operation. The survey was conducted at low altitude and with closely spaced flight lines to improve the detection of wells with weak magnetic response and to increase the resolution of closely spaced wells. The survey was in preparation for a planned CO2 flood to enhance oil recovery, which requires a complete well inventory with accurate locations for all existing wells. The magnetic survey was intended to locate wells that are missing from the well database and to provide accurate locations for all wells. The well location method used combined an input dataset (for example, leveled total magnetic field reduced to the pole), combined with first and second horizontal spatial derivatives of this input dataset, which were then analyzed using focal statistics and finally combined using a fuzzy combination operation. Analytic signal and the Shi and Butt (2004) ZS attribute were also analyzed using this algorithm. A parameter could be adjusted to determine sensitivity. Depending on the input dataset 88% to 100% of the wells were located, with typical values being 95% to 99% for the NPR3 field site.

  18. Diversity of Microbial Communities in Production and Injection Waters of Algerian Oilfields Revealed by 16S rRNA Gene Amplicon 454 Pyrosequencing

    Science.gov (United States)

    Lenchi, Nesrine; İnceoğlu, Özgül; Kebbouche-Gana, Salima; Gana, Mohamed Lamine; Llirós, Marc; Servais, Pierre; García-Armisen, Tamara

    2013-01-01

    The microorganisms inhabiting many petroleum reservoirs are multi-extremophiles capable of surviving in environments with high temperature, pressure and salinity. Their activity influences oil quality and they are an important reservoir of enzymes of industrial interest. To study these microbial assemblages and to assess any modifications that may be caused by industrial practices, the bacterial and archaeal communities in waters from four Algerian oilfields were described and compared. Three different types of samples were analyzed: production waters from flooded wells, production waters from non-flooded wells and injection waters used for flooding (water-bearing formations). Microbial communities of production and injection waters appeared to be significantly different. From a quantitative point of view, injection waters harbored roughly ten times more microbial cells than production waters. Bacteria dominated in injection waters, while Archaea dominated in production waters. Statistical analysis based on the relative abundance and bacterial community composition (BCC) revealed significant differences between production and injection waters at both OTUs0.03 and phylum level. However, no significant difference was found between production waters from flooded and non-flooded wells, suggesting that most of the microorganisms introduced by the injection waters were unable to survive in the production waters. Furthermore, a Venn diagram generated to compare the BCC of production and injection waters of one flooded well revealed only 4% of shared bacterial OTUs. Phylogenetic analysis of bacterial sequences indicated that Alpha-, Beta- and Gammaproteobacteria were the main classes in most of the water samples. Archaeal sequences were only obtained from production wells and each well had a unique archaeal community composition, mainly belonging to Methanobacteria, Methanomicrobia, Thermoprotei and Halobacteria classes. Many of the bacterial genera retrieved had already

  19. Classification using Hierarchical Naive Bayes models

    DEFF Research Database (Denmark)

    Langseth, Helge; Dyhre Nielsen, Thomas

    2006-01-01

    Classification problems have a long history in the machine learning literature. One of the simplest, and yet most consistently well-performing set of classifiers is the Naïve Bayes models. However, an inherent problem with these classifiers is the assumption that all attributes used to describe......, termed Hierarchical Naïve Bayes models. Hierarchical Naïve Bayes models extend the modeling flexibility of Naïve Bayes models by introducing latent variables to relax some of the independence statements in these models. We propose a simple algorithm for learning Hierarchical Naïve Bayes models...

  20. Latest results from Daya Bay

    Science.gov (United States)

    Vorobel, Vit; Daya Bay Collaboration

    2017-07-01

    The Daya Bay Reactor Neutrino Experiment was designed to measure θ 13, the smallest mixing angle in the three-neutrino mixing framework, with unprecedented precision. The experiment consists of eight functionally identical detectors placed underground at different baselines from three pairs of nuclear reactors in South China. Since Dec. 2011, the experiment has been running stably for more than 4 years, and has collected the largest reactor anti-neutrino sample to date. Daya Bay is able to greatly improve the precision on θ 13 and to make an independent measurement of the effective mass splitting in the electron antineutrino disappearance channel. Daya Bay can also perform a number of other precise measurements, such as a high-statistics determination of the absolute reactor antineutrino flux and spectrum, as well as a search for sterile neutrino mixing, among others. The most recent results from Daya Bay are discussed in this paper, as well as the current status and future prospects of the experiment.

  1. Daya bay reactor neutrino experiment

    International Nuclear Information System (INIS)

    Cao Jun

    2010-01-01

    Daya Bay Reactor Neutrino Experiment is a large international collaboration experiment under construction. The experiment aims to precisely determine the neutrino mixing angle θ 13 by detecting the neutrinos produced by the Daya Bay Nuclear Power Plant. θ 13 is one of two unknown fundamental parameters in neutrino mixing. Its magnitude is a roadmap of the future neutrino physics, and very likely related to the puzzle of missing antimatter in our universe. The precise measurement has very important physics significance. The detectors of Daya Bay is under construction now. The full operation is expected in 2011. Three years' data taking will reach the designed the precision, to determine sin 2 2θ 13 to better than 0.01. Daya Bay neutrino detector is an underground large nuclear detector of low background, low energy, and high precision. In this paper, the layout of the experiment, the design and fabrication progress of the detectors, and some highlighted nuclear detecting techniques developed in the detector R and D are introduced. (author)

  2. 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

  3. Spill management strategy for the Chesapeake Bay

    International Nuclear Information System (INIS)

    Butler, H.L.; Chapman, R.S.; Johnson, B.H.

    1990-01-01

    The Chesapeake Bay Program is a unique cooperative effort between state and Federal agencies to restore the health and productivity of America's largest estuary. To assist in addressing specific management issues, a comprehensive three-dimensional, time-varying hydrodynamic and water quality model has ben developed. The Bay modeling strategy will serve as an excellent framework for including submodules to predict the movement, dispersion, and weathering of accidental spills, such as for petroleum products or other chemicals. This paper presents sample results from the Bay application to illustrate the success of the model system in simulating Bay processes. Also, a review of model requirements for successful spill modeling in Chesapeake Bay is presented. Recommendations are given for implementing appropriate spill modules with the Bay model framework and establishing a strategy for model use in addressing management issues

  4. 75 FR 8297 - Tongass National Forest, Thorne Bay Ranger District, Thorne Bay, AK

    Science.gov (United States)

    2010-02-24

    ..., Thorne Bay, AK AGENCY: Forest Service, USDA. ACTION: Cancellation of Notice of intent to prepare an... Roberts, Zone Planner, Thorne Bay Ranger District, Tongass National Forest, P.O. Box 19001, Thorne Bay, AK 99919, telephone: 907-828-3250. SUPPLEMENTARY INFORMATION: The 47,007-acre Kosciusko Project Area is...

  5. 77 FR 44140 - Drawbridge Operation Regulation; Sturgeon Bay Ship Canal, Sturgeon Bay, WI

    Science.gov (United States)

    2012-07-27

    ... Maple-Oregon Bridges so vehicular traffic congestion would not develop on downtown Sturgeon Bay streets... movement of vehicular traffic in Sturgeon Bay. The Sturgeon Bay Ship Canal is approximately 8.6 miles long... significant increase in vehicular and vessel traffic during the peak tourist and navigation season between...

  6. The onset of deglaciation of Cumberland Bay and Stromness Bay, South Georgia

    NARCIS (Netherlands)

    Van Der Putten, N.; Verbruggen, C.

    Carbon dating of basal peat deposits in Cumberland Bay and Stromness Bay and sediments from a lake in Stromness Bay, South Georgia indicates deglaciation at the very beginning of the Holocene before c. 9500 14C yr BP. This post-dates the deglaciation of one local lake which has been ice-free since

  7. 78 FR 46813 - Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay, WI

    Science.gov (United States)

    2013-08-02

    ...-AA00 Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay, WI AGENCY: Coast Guard, DHS. ACTION.... This temporary safety zone will restrict vessels from a portion of Sturgeon Bay due to a fireworks... hazards associated with the fireworks display. DATES: This rule is effective from 8 p.m. until 10 p.m. on...

  8. Treatment of oilfield produced water using Fe/C micro-electrolysis assisted by zero-valent copper and zero-valent aluminium.

    Science.gov (United States)

    Zhang, Qi

    2015-01-01

    In this study, the Fe/Cu/C and Fe/Al/C inner micro-electrolysis systems were used to treat actual oilfield produced water to evaluate the feasibility of the technology. Effects of reaction time, pH value, the dosage of metals and activated carbon, and Fe:C mass ratio on the treatment efficiency of wastewater were studied. The results showed that the optimum conditions were reaction time 120 min, initial solution pH 4.0, Fe dosage 13.3 g/L, activated carbon dosage 6.7 g/L, Cu dosage 2.0 g/L or Al dosage 1.0 g/L. Under the optimum conditions, the removal efficiencies of chemical oxygen demand (COD) were 39.3%, 49.7% and 52.6% in the Fe/C, Fe/Cu/C and Fe/Al/C processes, respectively. Meanwhile, the ratio of five-day biochemical oxygen demand to COD was raised from 0.18 to above 0.35, which created favourable conditions for the subsequent biological treatment. All these led to an easy maintenance and low operational cost.

  9. The influence of water disposal method on the property of chemical oil-displacement agent--taking Guan 109-1 area of Dagang oilfield as example

    Directory of Open Access Journals (Sweden)

    Shengwang Yuan

    2018-03-01

    Full Text Available Aiming at the actual demand of Guan 109-1 block in Dagang oilfield, by means of instrumental analysis, chemical analysis, modern physical simulation, viewing polymer viscosity and seepage characteristic as evaluation index, the experimental research on the influence of water disposal method on the property of chemical oil-displacement agent was carried out. Results showed that through adding scaling agent, scale was formed because of the reaction between scaling agent and Ca2+, Mg2+ in the flooding water, which could enhance the viscosity of polymer solution. Through comparing the resistance factor and residual resistance factor of polymer solution which was respectively prepared with flooding water, softened water and scale, the resistance factor and residual resistance factor of polymer solution with scale was the largest, that of polymer solution prepared with softened water was second and that of polymer solution prepared with flooding water came last. Furthermore, scaling agent weakened the gelling effect between cross-linking agent Cr3+ and polymer molecule chains. The earlier the cross-linking agent Cr3+ was added, the larger the polymer viscosity, resistance factor and residual resistance factor of Cr3+ polymer were.

  10. Microbial communities inhabiting oil-contaminated soils from two major oilfields in Northern China: Implications for active petroleum-degrading capacity.

    Science.gov (United States)

    Sun, Weimin; Dong, Yiran; Gao, Pin; Fu, Meiyan; Ta, Kaiwen; Li, Jiwei

    2015-06-01

    Although oilfields harbor a wide diversity of microorganisms with various metabolic potentials, our current knowledge about oil-degrading bacteria is limited because the vast majority of oil-degrading bacteria remain uncultured. In the present study, microbial communities in nine oil-contaminated soils collected from Daqing and Changqing, two of the largest oil fields in China, were characterized through highthroughput sequencing of 16S rRNA genes. Bacteria related to the phyla Proteobacteria and Actinobacteria were dominant in four and three samples, respectively. At the genus level, Alkanindiges, Arthrobacter, Pseudomonas, Mycobacterium, and Rhodococcus were frequently detected in nine soil samples. Many of the dominant genera were phylogenetically related to the known oil-degrading species. The correlation between physiochemical parameters within the microbial communities was also investigated. Canonical correspondence analysis revealed that soil moisture, nitrate, TOC, and pH had an important impact in shaping the microbial communities of the hydrocarbon-contaminated soil. This study provided an in-depth analysis of microbial communities in oilcontaminated soil and useful information for future bioremediation of oil contamination.

  11. Unique thermal record in False Bay

    CSIR Research Space (South Africa)

    Grundlingh, ML

    1993-10-01

    Full Text Available Over the past decade False Bay has assumed a prime position in terms of research in to large South African bays. This is manifested by investigations that cover flow conditions modelling, thermal structure, management, biology and nutrients, geology...

  12. Hierarchical mixtures of naive Bayes classifiers

    NARCIS (Netherlands)

    Wiering, M.A.

    2002-01-01

    Naive Bayes classifiers tend to perform very well on a large number of problem domains, although their representation power is quite limited compared to more sophisticated machine learning algorithms. In this pa- per we study combining multiple naive Bayes classifiers by using the hierar- chical

  13. Safety culture development at Daya Bay NPP

    International Nuclear Information System (INIS)

    Zhang Shanming

    2001-01-01

    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

  14. The Holocene History of Placentia Bay, Newfoundland

    DEFF Research Database (Denmark)

    Sheldon, Christina; Seidenkrantz, Marit-Solveig; Reynisson, Njall

    2013-01-01

    Marine sediments analyzed from cores taken in Placentia Bay, Newfoundland, located in the Labrador Sea, captured oceanographic and climatic changes from the end of the Younger Dryas through the Holocene. Placentia Bay is an ideal site to capture changes in both the south-flowing Labrador Current ...

  15. Towards a sustainable future in Hudson Bay

    International Nuclear Information System (INIS)

    Okrainetz, G.

    1991-01-01

    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

  16. Bird surveys at McKinley Bay and Hutchison Bay, Northwest Territories, in 1991

    Energy Technology Data Exchange (ETDEWEB)

    Cornish, B J; Dickson, D L; Dickson, H L

    1992-03-01

    McKinley Bay is a shallow protected bay along the eastern Beaufort Sea coast which provides an important habitat for diving ducks. Since 1979, the bay has been the site of a winter harbor and support base for oil and gas exploraton in the Beaufort Sea. Aerial surveys for bird abundance and distribution were conducted in August 1991 as a continuation of long-term monitoring of birds in McKinley Bay and Hutchison Bay, a nearby area used as a control. The main objectives of the 1991 surveys were to expand the set of baseline data on natural annual fluctuations in diving duck numbers, and to determine if numbers of diving ducks had changed since the initial 1981-85 surveys. On the day with the best survey conditions, the population of diving ducks at McKinley bay was estimated at ca 32,000, significantly more than 1981-85. At Hutchison Bay, there were an estimated 11,000 ducks. As in previous years, large numbers of diving ducks were observed off Atkinson Point at the northwest corner of McKinley Bay, at the south end of the bay, and in the northeast corner near a long spit. Most divers in Hutchison Bay were at the west side. Diving ducks, primarily Oldsquaw and scoter, were the most abundant bird group in the study area. Observed distribution patterns of birds are discussed with reference to habitat preferences. 16 refs., 7 figs., 30 tabs.

  17. Holy grail at Baglan Bay

    International Nuclear Information System (INIS)

    Watson, Jim

    1999-01-01

    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)

  18. Combined treatment of hydroxypropyl guar gum in oilfield fracturing wastewater by coagulation and the UV/H2O2/ferrioxalate complexes process.

    Science.gov (United States)

    Zhang, Zhenchao

    2018-02-01

    Hydroxypropyl guar gum is considered to be a main component of oilfield fracturing wastewater (OFW). This work is intended to optimize the experimental conditions for the maximum oxidative degradation of hydroxypropyl guar gum by the coagulation and UV/H 2 O 2 /ferrioxalate complexes process. Optimal reaction conditions were proposed based on the chemical oxygen demand (COD) removal efficiency and UV _ vis spectra analysis. The overall removal efficiency of COD reached 83.8% for a dilution ratio of raw wastewater of 1:2, pH of 4 and FeCl 3 loading of 1,000 mg/L in the coagulation process; the dosage of H 2 O 2 (30%,v/v) was 0.6% (v/v) and added in three steps, the n(H 2 O 2 )/n(Fe 2+ ) was 2:1, n(Fe 2+ )/n(C 2 O 4 2- ) was 3:1 and pH was 4 in the UV/H 2 O 2 /ferrioxalate complexes process; pH was adjusted to 8.5-9 by NaOH and then cationic polyacrylamide (CPAM) of 2 mg/L was added in the neutralization and flocculation process. The decrease in COD during the coagulation process reduced the required H 2 O 2 dosage and improved efficiency in the subsequent UV/H 2 O 2 /ferrioxalate complexes process. Furthermore, COD removal efficiency significantly increased by more than 13.4% with the introduction of oxalate compared with UV/Fenton. The UV _ vis spectra analysis results indicated that the coagulation and UV/H 2 O 2 /ferrioxalate complexes process could efficiently remove the hydroxypropyl guar gum dissolved in OFW. An optimal combination of these parameters produced treated wastewater that met the GB8978-1996 Integrated Wastewater Discharge Standard level III emission standard.

  19. Combined treatment of organic material in oilfield fracturing wastewater by coagulation and UV/H2O2/ferrioxalate complexes process.

    Science.gov (United States)

    Ge, Dan

    2018-02-01

    Organic material is considered to be a main component of oilfield fracturing wastewater (OFW). This work is intended to optimize the experimental conditions for the maximum oxidative degradation of organic material by coagulation and the UV/H 2 O 2 /ferrioxalate complexes process. Optimal reaction conditions are proposed based on the chemical oxygen demand (COD) removal efficiency. The overall removal efficiency of COD reached 83.8% when the dilution ratio of raw wastewater was 1:2, the pH was 4 and the FeCl 3 loading was 1,000 mg/L in the coagulation process; the dosage of H 2 O 2 (30%,v/v) was 0.6% (v/v) and added in three steps, the n(H 2 O 2 )/n(Fe 2+ ) was 2:1, n(Fe 2+ )/n(C 2 O 4 2- ) was 3:1 and the pH was 4 in the UV/H 2 O 2 /ferrioxalate complexes process; the pH was adjusted to 8.5-9 with NaOH and then 2 mg/L of cationic polyacrylamide (CPAM) was added in the neutralization and flocculation process. The decrease in COD during the coagulation process reduced the required H 2 O 2 dosage and improve efficiency in the subsequent UV/H 2 O 2 /ferrioxalate complexes process. Furthermore, there was a significant increase of 13.4% in the COD removal efficiency with the introduction of oxalate compared with UV/Fenton. Experimental results show that the coagulation and UV/H 2 O 2 /ferrioxalate complexes process could efficiently remove the organic material dissolved in OFW. An optimal combination of these parameters produced treated wastewater that met the GB8978-1996' Integrated Wastewater Discharge Standard' level III emission standard.

  20. The Schoonebeek Oilfield: the Rw-2e High Pressure Steam Injection Project Gisement de Schoonebeek : le projet RW-2E d'injection de vapeur à haute pression

    Directory of Open Access Journals (Sweden)

    Holtam V. R.

    2006-11-01

    Full Text Available The daily oil production from the Schoonebeek Oilfield amounts to some 1400 m3 /d, of which ca. 65% is produced from a high pressure (85 bar steam injection project. This project was started in 1981 and originally consisted of 7 structurally downdip/middip steam injectors. However, following the initially somewhat disappointing project performance, steam injection was moved to 4 middip/ updip injectors in 1984. This change in the location of the steam injectors, together with an increase in the level of surveillance and a more pragmatic reservoir management policy, has resulted in improved project performance. The ultimate extra oil/steam ratio for the total project is now expected to be 0. 7 m3 oil/ton of steam injected. La production de pétrole du gisement de Schoonebeek est d'environ 1400 m3/jour, dont près de 65% sont obtenus par injection de vapeur à haute pression (85 bar. Ce projet lancé en 1981 comportait initialement 7 injecteurs de vapeur orientés vers l'aval-pendage. En raison de performances décevantes, l'injection de vapeur a été transférée en 1984 sur 4 injecteurs travaillant vers l'amont-pendage. Ce changement de position des injecteurs, accompagné d'une surveillance renforcée et d'une politique de gestion du gisement plus pragmatique, a donné des résultats favorables. On pense que le rapport pétrole/vapeur pour l'ensemble du projet devrait être en dernière analyse de 0,7 m3 de pétrole par tonne de vapeur injectée.

  1. 78 FR 62293 - Safety Zone, Oyster Festival 30th Anniversary Fireworks Display, Oyster Bay; Oyster Bay, NY

    Science.gov (United States)

    2013-10-15

    ... Safety Zone, Oyster Festival 30th Anniversary Fireworks Display, Oyster Bay; Oyster Bay, NY AGENCY: Coast... zone on the navigable waters of Oyster Bay near Oyster Bay, NY for the Oyster Festival 30th Anniversary... Oyster Festival 30th Anniversary Fireworks Display is scheduled for October 19, 2013 and is one of...

  2. 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 Island...

  3. 78 FR 27126 - East Bay, St. Andrews Bay and the Gulf of Mexico at Tyndall Air Force Base, Florida; Restricted...

    Science.gov (United States)

    2013-05-09

    ... DEPARTMENT OF DEFENSE Department of the Army, Corps of Engineers 33 CFR Part 334 East Bay, St. Andrews Bay and the Gulf of Mexico at Tyndall Air Force Base, Florida; Restricted Areas AGENCY: U.S. Army... read as follows: Sec. 334.665 East Bay, St. Andrews Bay and the Gulf of Mexico, Restricted Areas...

  4. 75 FR 15343 - Regulated Navigation Area: Narragansett Bay, RI and Mount Hope Bay, RI and MA, Including the...

    Science.gov (United States)

    2010-03-29

    ...: Narragansett Bay, RI and Mount Hope Bay, RI and MA, Including the Providence River and Taunton River AGENCY... River and Mount Hope Bay in the vicinity of the two Brightman Street bridges have not been adopted and... Island and Mt. Hope Bay, MA.'' The notice was prompted primarily by two events: (1) The U.S. Army Corps...

  5. Description of gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

    Science.gov (United States)

    Woodrow, Donald L.; John L. Chin,; Wong, Florence L.; Fregoso, Theresa A.; Jaffe, Bruce E.

    2017-06-27

    Seventy-two gravity cores were collected by the U.S. Geological Survey in 1990, 1991, and 2000 from San Pablo Bay and Carquinez Strait, California. The gravity cores collected within San Pablo Bay contain bioturbated laminated silts and sandy clays, whole and broken bivalve shells (mostly mussels), fossil tube structures, and fine-grained plant or wood fragments. Gravity cores from the channel wall of Carquinez Strait east of San Pablo Bay consist of sand and clay layers, whole and broken bivalve shells (less than in San Pablo Bay), trace fossil tubes, and minute fragments of plant material.

  6. 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...

  7. 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...

  8. 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...

  9. 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...

  10. 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...

  11. San Francisco Bay Interferometric Bathymetry: Area B

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — High resolution sonar data were collected over ultra-shallow areas of the San Francisco Bay estuary system. Bathymetric and acoustic backscatter data were collected...

  12. 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...

  13. 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...

  14. 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...

  15. Benthic harpacticoid copepods of Jiaozhou Bay, Qingdao

    Science.gov (United States)

    Ma, Lin; Li, Xinzheng

    2017-09-01

    The species richness of benthic harpacticoid copepod fauna in Jiaozhou Bay, Qingdao, on the southern coast of Shandong Peninsula, has not been comprehensively studied. We present a preliminary inventory of species for this region based on material found in nine sediment samples collected from 2011 to 2012. Our list includes 15 species belonging to 15 genera in 9 families, the most speciose family was the Miraciidae Dana, 1846 (seven species); all other families were represented by single species only. Sediment characteristics and depth are determined to be important environmental determinants of harpacticoid distribution in this region. We briefly detail the known distributions of species and provide a key to facilitate their identification. Both harpacticoid species richness and the species/genus ratio in Jiaozhou Bay are lower than in Bohai Gulf and Gwangyang Bay. The poor knowledge of the distribution of benthic harpacticoids, in addition to low sampling effort in Jiaozhou Bay, likely contribute to low species richness.

  16. 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 nearshore...

  17. 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:

  18. Toxic phytoplankton in San Francisco Bay

    Science.gov (United States)

    Rodgers, Kristine M.; Garrison, David L.; Cloern, James E.

    1996-01-01

    The Regional Monitoring Program (RMP) was conceived and designed to document the changing distribution and effects of trace substances in San Francisco Bay, with focus on toxic contaminants that have become enriched by human inputs. However, coastal ecosystems like San Francisco Bay also have potential sources of naturally-produced toxic substances that can disrupt food webs and, under extreme circumstances, become threats to public health. The most prevalent source of natural toxins is from blooms of algal species that can synthesize metabolites that are toxic to invertebrates or vertebrates. Although San Francisco Bay is nutrient-rich, it has so far apparently been immune from the epidemic of harmful algal blooms in the world’s nutrient-enriched coastal waters. This absence of acute harmful blooms does not imply that San Francisco Bay has unique features that preclude toxic blooms. No sampling program has been implemented to document the occurrence of toxin-producing algae in San Francisco Bay, so it is difficult to judge the likelihood of such events in the future. This issue is directly relevant to the goals of RMP because harmful species of phytoplankton have the potential to disrupt ecosystem processes that support animal populations, cause severe illness or death in humans, and confound the outcomes of toxicity bioassays such as those included in the RMP. Our purpose here is to utilize existing data on the phytoplankton community of San Francisco Bay to provide a provisional statement about the occurrence, distribution, and potential threats of harmful algae in this Estuary.

  19. 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.

  20. Use of Remote Sensing Data and GIS Tools for Seismic Hazard Assessment for Shallow Oilfields and its Impact on the Settlements at Masjed-i-Soleiman Area, Zagros Mountains, Iran

    Directory of Open Access Journals (Sweden)

    Hojjat Ollah Safari

    2010-05-01

    Full Text Available Masjed-i-Soleiman (MIS is situated in the northern part of the Dezful embayment, which is in the Zagros fold–thrust belt with high seismic activities. MIS faces a shallow buried anticline, formed by the shallowest oilfield with a thick gas cap. The cap rocks of this oilfield are highly fractured, which has resulted in leakages from the gas cap. In this paper, we have used remote sensing techniques and image interpretation for the identification of the Niayesh, Lahbari, Andika and MIS fault zones in the studied area. Further, the study exploited seismic potential mapping using the remote sensing techniques. The relationships between the structural controls and localized gas leakage are assessed within the GIS environment. Additionally, field observation data corroborated that the leakages (and seepages are smashed within the intersection of Niayesh and MIS fault zone, which belongs to the high fractured hinge zone of the MIS anticline. As a result, the reactivation of these active faults may cause large earthquakes with a maximum magnitude of between 6.23 < Ms < 7.05 (Richter scale and maximum horizontal acceleration 0.26 < a < 0.55 g. Finally, the authors concluded that this anticipated earthquake may cause large scale fracturing of cap rocks, releasing a large volume of H2S gas from the uppermost layer of the reservoir.

  1. 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...

  2. 77 FR 21890 - Drawbridge Operation Regulation; Sturgeon Bay Ship Canal, Sturgeon Bay, WI

    Science.gov (United States)

    2012-04-12

    ... Street and Maple-Oregon Bridges so vehicular traffic congestion would not develop on downtown Sturgeon... the efficient movement of vehicular traffic in Sturgeon Bay. The Sturgeon Bay Ship Canal is... experiences a significant increase in vehicular and vessel traffic during the peak tourist and navigation...

  3. 76 FR 28309 - Drawbridge Operation Regulation; Sturgeon Bay Ship Canal, Sturgeon Bay, WI

    Science.gov (United States)

    2011-05-17

    ... vehicular traffic congestion would not develop on downtown Sturgeon Bay streets due to unscheduled bridge... schedules during the peak tourist and navigation seasons to provide for the efficient movement of vehicular... between Lake Michigan and Green Bay. The area experiences a significant increase in vehicular and vessel...

  4. Cambridge Bay: Six years later

    International Nuclear Information System (INIS)

    Edworthy, J.

    1992-01-01

    The story of a wind energy project in Cambridge Bay, Northwest Territories, is presented from the perspective of the company that supplied the equipment and supported the project through its life. The project was intended to demonstrate the technical, economic, institutional, and operational issues and barriers to the use of wind power in remote communities. The system, involving four Carter Model 25 units each rated at 25 kW, was installed in 1987 and commissioned in January 1988. Shortly thereafter, the Northern Canada Power Commission (which requested the project in the first place) was taken over by the territorial administration, and employee continuity was disrupted. At about the same time, Federal support for the project decreased. Technical problems included a transformer failure, a generator failure, and a failed yaw tube which turned out to be lightly designed and poorly made. The Carter turbine company also went out of business, making spare parts difficult to obtain. The utility organization changed abruptly in summer 1991 with the arrival of a new area superintendent who did not support the project. The wind farm was shut down in 1992. The project generated a total of 160,982 kWh with over 71% availability. The positive and negative results from the project are summarized and recommendations are made for future Arctic wind power projects. 2 figs., 1 tab

  5. 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.

  6. Concentration of PSP (Paralytic Shellfish Poisoning) Toxin On Shellfish From Inner Ambon Bay and Kao Bay North Halmahera

    Science.gov (United States)

    Pello, F. S.; Haumahu, S.; Huliselan, N. V.; Tuapattinaja, M. A.

    2017-10-01

    The Inner Ambon Bay and Kao Bay have potential on fisheries resources which one of them is molluscs. Molluscs especially for class bivalve have economical values and are consumed by coastal community. The research had been done to analyze saxitoxin (STX) concentration on bivalves from Kao Bay and Inner Ambon Bay. The Saxitoxin Elisa Test Kit Protocol was used to determine saxitoxin concentration. The measurement showed that the highest concentration of saxitoxin (392.42 µg STXeq/100g shellfish meat) was Gafrarium tumidum from Ambon Bay, whereas concentration of saxitoxin (321.83 µg STXeq/100g shellfish meat) was Mactra mera from Kao Bay

  7. PEMANFATAN TEOREMA BAYES DALAM PENENTUAN PENYAKIT THT

    Directory of Open Access Journals (Sweden)

    Sri Winiarti

    2008-07-01

    Full Text Available Dalam konsep pelacakan dalam mencari solusi dengan pendekatan artificial inteligent, ada berbagai metode yang dapat diterapkan untuk mengatasi masalah ketidakpastian saat proses pelacakan terjadi. Salah satunya adalah teorema bayes. Adanya ketidakpastian pada proses pelacakan dapat terjadi karena adanya perubahan pengetahuan yang ada di dalam sistem. Untuk itu diperlukan adanya suatu metode untuk mengatasi permasalahan tersebut. Dalam penelitian ini telah diterapkan suatu metode untuk mengatasi ketidakpastian dengan teorema Bayes pada kasus pelacakan untuk mendiagnosa penyakit pada THT (Telinga,Hidung dan Tenggorokan. Subjek pada penelitian ini adalah proses pelacakan untuk menentukan penyakit THT dengan model penalaran forward chaining dan metode kepastiannya menggunakan teorema bayes dengan cara menghitung nilai probabilitas suatu penyakit dan membandingkan probabilitas setiap gejalanya. Model pengembangan perangkat lunak yang digunakan dalam penelitian ini adalah Waterfall. Metode Waterfall diawali dengan analisis data, perancangan sistem, pengkodean menggunakan Visual Basic 6.0, pengujian sistem dengan black box test dan alfa test. Dari penelitian yang dilakukan menghasilkan sebuah perangkat lunak yaitu yang mampu menentukan penyakit pada THT dengan menerapkan metode bayes untuk mengatasi ketidakpastian. Hasil uji coba sistem menujukkan bahwa aplikasi ini layak dan dapat digunakan. Kata kunci : Penyakit, THT, Teorema Bayes.

  8. Changing Salinity Patterns in Biscayne Bay, Florida

    Science.gov (United States)

    ,

    2004-01-01

    Biscayne Bay, Fla., is a 428-square-mile (1,109-square-kilometer) subtropical estuarine ecosystem that includes Biscayne National Park, the largest marine park in the U.S. national park system (fig. 1). The bay began forming between 5,000 and 3,000 years ago as sea level rose and southern Florida was flooded. Throughout most of its history, the pristine waters of the bay supported abundant and diverse fauna and flora, and the bay was a nursery for the adjacent coral-reef and marine ecosystems. In the 20th century, urbanization of the Miami-Dade County area profoundly affected the environment of the bay. Construction of powerplants, water-treatment plants, and solid-waste sites and large-scale development along the shoreline stressed the ecosystem. Biscayne National Monument was established in 1968 to ?preserve and protect for the education, inspiration, recreation and enjoyment of present and future generations a rare combination of terrestrial, marine, and amphibious life in a tropical setting of great natural beauty? (Public Law 90?606). The monument was enlarged in 1980 and designated a national park.

  9. 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.; Shenoy, Shrikant

    Surface layer temperature inversion occurring in the Bay of Bengal has been addressed. Hydrographic data archived in the Indian Oceanographic Data Center are used to understand various aspects of the temperature inversion of surface layer in the Bay...

  10. Parameter Identification by Bayes Decision and Neural Networks

    DEFF Research Database (Denmark)

    Kulczycki, P.; Schiøler, Henrik

    1994-01-01

    The problem of parameter identification by Bayes point estimation using neural networks is investigated.......The problem of parameter identification by Bayes point estimation using neural networks is investigated....

  11. SF Bay Water Quality Improvement Fund: Projects and Accomplishments

    Science.gov (United States)

    San Francisco Bay Water Quality Improvement Fund (SFBWQIF) projects listed here are part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  12. South Bay Salt Pond Tidal Wetland Restoration Phase II Planning

    Science.gov (United States)

    Information about the SFBWQP South Bay Salt Pond Tidal Wetland Restoration Phase II Planning project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic re

  13. South Bay Salt Pond Restoration, Phase II at Ravenswood

    Science.gov (United States)

    Information about the South Bay Salt Pond Restoration Project: Phase II Construction at Ravenswood, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  14. 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,...

  15. 1999 RoxAnn Data Points from 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,...

  16. Meteorological research studies at Jervis Bay, Australia

    International Nuclear Information System (INIS)

    Clark, G.H.; Bendun, E.O.K.

    1974-07-01

    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)

  17. 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.

  18. Mapping Oyster Reef Habitats in Mobile Bay

    Science.gov (United States)

    Bolte, Danielle

    2011-01-01

    Oyster reefs around the world are declining rapidly, and although they haven t received as much attention as coral reefs, they are just as important to their local ecosystems and economies. Oyster reefs provide habitats for many species of fish, invertebrates, and crustaceans, as well as the next generations of oysters. Oysters are also harvested from many of these reefs and are an important segment of many local economies, including that of Mobile Bay, where oysters rank in the top five commercial marine species both by landed weight and by dollar value. Although the remaining Mobile Bay oyster reefs are some of the least degraded in the world, projected climate change could have dramatic effects on the health of these important ecosystems. The viability of oyster reefs depends on water depth and temperature, appropriate pH and salinity levels, and the amount of dissolved oxygen in the water. Projected increases in sea level, changes in precipitation and runoff patterns, and changes in pH resulting from increases in the amount of carbon dioxide dissolved in the oceans could all affect the viability of oyster reefs in the future. Human activities such as dredging and unsustainable harvesting practices are also adversely impacting the oyster reefs. Fortunately, several projects are already under way to help rebuild or support existing or previously existing oyster reefs. The success of these projects will depend on the local effects of climate change on the current and potential habitats and man s ability to recognize and halt unsustainable harvesting practices. As the extent and health of the reefs changes, it will have impacts on the Mobile Bay ecosystem and economy, changing the resources available to the people who live there and to the rest of the country, since Mobile Bay is an important national source of seafood. This project identified potential climate change impacts on the oyster reefs of Mobile Bay, including the possible addition of newly viable

  19. Lost lake - restoration of a Carolina bay

    Energy Technology Data Exchange (ETDEWEB)

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

    1994-09-01

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

  20. Retrospective application of the "guidelines for monitoring mining subsurface activities for hydrocarbons exploitation, re-injection and storage activities (ILG)": insights from the analysis of 2012-2013 Emilia seismic sequence at the Cavone oilfield pilot site (Italy)

    Science.gov (United States)

    Buttinelli, M.; Chiarabba, C.; Anselmi, M.; Pezzo, G.; Improta, L.; Antoncecchi, I.

    2017-12-01

    In recent years, the debate on the interactions between wastewater disposal and induced seismicity is increasingly drawing the attention of the scientific community, since injections by high-rate wells have been directly associated to occurrence of even large seismic events. In February 2014, the Italian Ministry of Economic Development (MiSE), within the Commission on Hydrocarbon and Mining Resources (CIRM), issued the "guidelines for monitoring mining subsurface activities for hydrocarbons exploitation, re-injection and storage activities (ILG)". The ILG represent the first action in italy aimed at keeping the safety standards mostly in areas where the underground resources exploitation can induce seismicity, ground deformations and pore pressure changes of the reservoirs. Such guidelines also launched a "traffic light" operating system, for the first time defining threshold values and activation levels for such monitored parameters. To test the ILG implications (in particular of the traffic light system) we select the Cavone oilfield (Northern Italy) as test case, since this area was interested during the 2012-2013 by the Emilia Seismic sequence. Moreover, the potential influence of the Cavone oilfield activities in the 2012 earthquake trigger was debated for a long time within the scientific and not contexts, highlighting the importance of seismic monitoring in hydrocarbons exploitation, re-injection and storage areas. In this work we apply the ILG retrospectively to the Cavone oilfield and surrounding areas, just for the seismicity parameter (pore pressure and ground deformation were not taken into account because out of the traffic light system). Since each seismicity catalogue available for the 2012 sequence represents a different setting of monitoring system, we carefully analyzed how the use of such catalogues impact on the overcoming of the threshold imposed by the ILG. In particular, we focus on the use of 1D and 3D velocity models developed ad hoc or

  1. STS-98 Destiny in Atlantis's payload bay

    Science.gov (United States)

    2001-01-01

    KENNEDY SPACE CENTER, Fla. -- The U.S. Laboratory Destiny rests once again in Atlantis'''s payload bay, at Launch Pad 39A. Closing of the payload bay doors is imminent. Destiny, a key element in the construction of the International Space Station, is 28 feet long and weighs 16 tons. This research and command-and-control center is the most sophisticated and versatile space laboratory ever built. It will ultimately house a total of 23 experiment racks for crew support and scientific research. Destiny will be launched Feb. 7 on STS-98, the seventh construction flight to the ISS.

  2. Management case study: Tampa Bay, Florida

    Science.gov (United States)

    Morrison, G.; Greening, H.S.; Yates, K.K.

    2012-01-01

    Tampa Bay, Florida,USA, is a shallow,subtropical estuary that experienced severe cultural eutrophication between the 1940s and 1980s, a period when the human population of its watershed quadrupled. In response, citizen action led to the formation of a public- and private-sector partnership (the Tampa Bay Estuary Program), which adopted a number of management objectives to support the restoration and protection of the bay’s living resources. These included numeric chlorophyll a and water-clarity targets, as well as long-term goals addressing the spatial extent of sea grasses and other selected habitat types, to support estuarine-dependent faunal guilds.

  3. Chondrichthyan occurrence and abundance trends in False Bay ...

    African Journals Online (AJOL)

    Commercial fishing in False Bay, South Africa, began in the 1600s. Today chondrichthyans are regularly taken in fisheries throughout the bay. Using a combination of catch, survey and life history data, the occurrence and long-term changes in populations of chondrichthyans in False Bay are described. Analyses of time ...

  4. Improved oilfield GHG accounting using a global oilfield database

    Science.gov (United States)

    Roberts, S.; Brandt, A. R.; Masnadi, M.

    2016-12-01

    The definition of oil is shifting in considerable ways. Conventional oil resources are declining as oil sands, heavy oils, and others emerge. Technological advances mean that these unconventional hydrocarbons are now viable resources. Meanwhile, scientific evidence is mounting that climate change is occurring. The oil sector is responsible for 35% of global greenhouse gas (GHG) emissions, but the climate impacts of these new unconventional oils are not well understood. As such, the Oil Climate Index (OCI) project has been an international effort to evaluate the total life-cycle environmental GHG emissions of different oil fields globally. Over the course of the first and second phases of the project, 30 and 75 global oil fields have been investigated, respectively. The 75 fields account for about 25% of global oil production. For the third phase of the project, it is aimed to expand the OCI to contain closing to 100% of global oil production; leading to the analysis of 8000 fields. To accomplish this, a robust database system is required to handle and manipulate the data. Therefore, the integration of the data into the computer science language SQL (Structured Query Language) was performed. The implementation of SQL allows users to process the data more efficiently than would be possible by using the previously established program (Microsoft Excel). Next, a graphic user interface (gui) was implemented, in the computer science language of C#, in order to make the data interactive; enabling people to update the database without prior knowledge of SQL being necessary.

  5. 76 FR 22809 - Safety Zone; Bay Ferry II Maritime Security Exercise; San Francisco Bay, San Francisco, CA

    Science.gov (United States)

    2011-04-25

    ... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2011-0196] RIN 1625-AA00 Safety Zone; Bay Ferry II Maritime Security Exercise; San Francisco Bay, San Francisco, CA AGENCY... Security Exercise; San Francisco Bay, San Francisco, CA. (a) Location. The limits of this safety zone...

  6. Marine littoral diatoms from the Gordon’s bay region of False Bay, Cape Province, South Africa

    CSIR Research Space (South Africa)

    Giffen, MH

    1971-01-01

    Full Text Available and Comic/i for Scientific and Industrial Research, Pretoria (Received: 5.2. 1970) The Gordon?s Bay region occupies the north western corner of False Bay, a large rectangular bay, bounded on the west by the Cape Peninsula ending at Cape Point...

  7. San Francisco Bay Water Quality Improvement Fund Points, SF Bay CA, 2015, US EPA Region 9

    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...

  8. 77 FR 57107 - Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife Refuges, Coos, Tillamook, and...

    Science.gov (United States)

    2012-09-17

    ... environmental, recreational, and socio-economic benefits and impacts of our LPP alternatives, and respond to... eco-tourism or natural resource-based visitor centers. Nestucca Bay NWR Alternative A: No Action Under...

  9. 75 FR 73121 - Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife Refuges, Coos, Tillamook, and...

    Science.gov (United States)

    2010-11-29

    ... County, Oregon. The refuge was established in 1991 with the acquisition of a 384-acre dairy farm, and has... pastures at Nestucca Bay NWR to tidal marsh, and what effect would this have on the refuge's ability to...

  10. Pärnu Bay Golf Club = Pärnu Bay Golf Club / Arhitekt11

    Index Scriptorium Estoniae

    2016-01-01

    Pärnu Bay Golf Club, arhitektid Jürgen Lepper, Anto Savi, Margus Soonets, Janar Toomesso (Arhitekt11), sisearhitektid Liina Vaino, Kaari Metslang, Hannelore Kääramees (Arhitekt11). Kultuurkapitali Arhitektuuri sihtkapitali aastapreemia nominent 2016

  11. Discharge between San Antonio Bay and Aransas Bay, southern Gulf Coast, Texas, May-September 1999

    Science.gov (United States)

    East, Jeffery W.

    2001-01-01

    Along the Gulf Coast of Texas, many estuaries and bays are important habitat and nurseries for aquatic life. San Antonio Bay and Aransas Bay, located about 50 and 30 miles northeast, respectively, of Corpus Christi, are two important estuarine nurseries on the southern Gulf Coast of Texas (fig. 1). According to the Texas Parks and Wildlife Department, “Almost 80 percent of the seagrasses [along the Texas Gulf Coast] are located in the Laguna Madre, an estuary that begins just south of Corpus Christi Bay and runs southward 140 miles to South Padre Island. Most of the remaining seagrasses, about 45,000 acres, are located in the heavily traveled San Antonio, Aransas and Corpus Christi Bay areas” (Shook, 2000).Population growth has led to greater demands on water supplies in Texas. The Texas Water Development Board, the Texas Parks and Wildlife Department, and the Texas Natural Resource Conservation Commission have the cooperative task of determining inflows required to maintain the ecological health of the State’s streams, rivers, bays, and estuaries. To determine these inflow requirements, the three agencies collect data and conduct studies on the need for instream flows and freshwater/ saline water inflows to Texas estuaries.To assist in the determination of freshwater inflow requirements, the U.S. Geological Survey (USGS), in cooperation with the Texas Water Development Board, conducted a hydrographic survey of discharge (flow) between San Antonio Bay and Aransas Bay during the period May–September 1999. Automated instrumentation and acoustic technology were used to maximize the amount and quality of data that were collected, while minimizing personnel requirements. This report documents the discharge measured at two sites between the bays during May–September 1999 and describes the influences of meteorologic (wind and tidal) and hydrologic (freshwater inflow) conditions on discharge between the two bays. The movement of water between the bays is

  12. 77 FR 30443 - Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY

    Science.gov (United States)

    2012-05-23

    ...The Coast Guard proposes to establish a temporary safety zone on the St. Lawrence River, Alexandria Bay, NY. This proposed rule is intended to restrict vessels from a portion of the St. Lawrence River during the Alexandria Bay Chamber of Commerce fireworks display. The safety zone established by this proposed rule is necessary to protect spectators and vessels from the hazards associated with a fireworks display.

  13. Chesapeake Bay baseline data acquisition, toxics in the Chesapeake Bay. Final preliminary report, 1946-78

    International Nuclear Information System (INIS)

    1978-07-01

    This report identifies researchers, research activities, and data files applicable to the Chesapeake Bay estuarine system. The identified data were generated after 1973 on the following: submerged aquatic vegetation, shellfish bed closures, eutrophication, toxics accumulation in the food chain, dredging and spoil disposal, hydrologic modifications, modification of fisheries, shoreline erosion, wetlands alterations, and the effects of boating and shipping on water quality. Major past and current program monitoring in the Bay and its tributaries are summarized according to frequency

  14. Elemental analysis of Uranouchi bay seabed sludge using PIXE

    International Nuclear Information System (INIS)

    Kabir, M. Hasnat; Narusawa, Tadashi; Nishiyama, Fumitaka; Sumi, Katsuhiro

    2006-01-01

    Elemental analyses were carried out for the seabed sludge collected from Uranouchi bay (Kochi, Japan) using Particle Induced X-ray Emission (PIXE). Seabed-sludge contamination with heavy metals as well as toxic elements becomes one of the most serious environmental problems. The aim of the present study is to investigate the polluted areas in the bay by heavy and toxic elements. As a results of analyses of samples collected from eleven different places in the bay, seventeen elements including toxic ones were detected. The results suggest that the center region of the bay is seriously contaminated by heavy and toxic elements in comparison with the other areas in the bay. (author)

  15. CURRENT DIRECTION, turbidity and other data from FIXED STATIONS, DRIFTING PLATFORM and UNKNOWN in the Beaufort Sea from 1985-01-01 to 1988-12-31 (NODC Accession 9400070)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The database from the Endicott Environmental Monitoring Program contains oceanographic, meterological, and fisheries data for the Prudhoe Bay region (North Alaska,...

  16. PEMANFATAN TEOREMA BAYES DALAM PENENTUAN PENYAKIT THT

    Directory of Open Access Journals (Sweden)

    Sri Winiarti

    2012-05-01

    Full Text Available Dalam konsep pelacakan dalam mencari solusi dengan pendekatan artificial inteligent, ada berbagai metode  yang dapat diterapkan untuk mengatasi masalah ketidakpastian saat proses pelacakan terjadi. Salah satunya adalah teorema bayes. Adanya ketidakpastian pada proses pelacakan dapat terjadi karena adanya perubahan pengetahuan yang ada di dalam sistem. Untuk itu diperlukan adanya suatu metode untuk mengatasi permasalahan tersebut. Dalam penelitian ini telah diterapkan suatu metode untuk mengatasi ketidakpastian dengan teorema Bayes pada kasus pelacakan untuk mendiagnosa penyakit pada THT (Telinga,Hidung dan Tenggorokan.  Subjek pada penelitian ini adalah proses pelacakan untuk menentukan penyakit THT dengan model penalaran forward chaining dan metode kepastiannya menggunakan teorema bayes dengan cara menghitung nilai probabilitas suatu penyakit dan membandingkan probabilitas setiap gejalanya. Model pengembangan perangkat lunak yang digunakan dalam penelitian ini adalah Waterfall. Metode Waterfall diawali dengan analisis data, perancangan sistem, pengkodean menggunakan Visual Basic 6.0, pengujian sistem dengan black box test dan alfa test. Dari penelitian yang dilakukan menghasilkan sebuah perangkat lunak yaitu  yang mampu menentukan penyakit pada THT dengan menerapkan metode bayes untuk mengatasi ketidakpastian. Hasil uji coba sistem menujukkan bahwa aplikasi ini layak dan dapat digunakan.

  17. Radioactive source management in Daya Bay NPP

    International Nuclear Information System (INIS)

    Mao Chun Yang

    2000-01-01

    'Small sources causes big accidents' had occurred worldwide many times. Radioactive source management in Nuclear Power Plant in very important for its safety record. This paper introduces the way and experience of radioactive source management in Daya Bay NPP from aspects of clarifying the responsibilities, centralizing the management of high radioactivity sources, work process management and experience feedback etc. (author)

  18. 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...

  19. Sediment Characterization in St. Alban's Bay, VT

    Science.gov (United States)

    Nethercutt, S.; Manley, T.; Manley, P.

    2017-12-01

    St. Alban's Bay within Lake Champlain is plagued with harmful algal blooms. With future intensification due to climate change, a multidisciplinary program (BREE-Basin Resilience to Extreme Events) was initiated in 2016. In order to assess the mobilization of harmful nutrients from sediment resuspension events and riverine input, 74 sediment samples were collected in a grid fashion throughout St. Alban's Bay. Sediments were deflocculated and analyzed using a LA920 Horiba laser scattering particle size distribution analyzer to define the frequency of sediment sizes from clay to sand. Gridded surfaces of mean sortable silt percentage, silt percentage, sand percentage, and clay percentage were used to represent the sediment distribution of the region. A plot of diameter versus frequency showed the bimodal nature of some of the sediments, with one peak at about 10 microns diameter (silt) and the second at about 525 microns diameter (sand). The data showed an extremely low percentage of clay relative to that of sand and silt. The highest frequencies of sortable silt, which represents the most easily mobilized particle size, are found in the deepest areas of the bay, suggesting that these regions are where dominant bottom flow occurs. The high occurrence of sortable silt in the St. Alban's Bay does suggest that sediment mobilization, and therefore nutrient mobilization has the potential to occur. These data combined with high-resolution multibeam and hydrodynamic data will allow for future models of water flow and remobilization studies in the future.

  20. Underwater Gravity Survey of Northern Monterey Bay.

    Science.gov (United States)

    stations were occupied just above the swash zone. A complete Bouguer anomaly map was drawn and tied in with the previous land surveys and with one...covering the southern half of the bay. The isolines of the complete Bouguer anomaly indicate the relative vertical position of the basement complex Santa

  1. Padilla Bay: The Estuary Guide. Level 2.

    Science.gov (United States)

    Friesem, Judy; Lynn, Valerie, Ed.

    Estuaries are marine systems that serve as nurseries for animals, links in the migratory pathways, and habitat for a complex community of organisms. This curriculum guide intended for use at the middle school level is designed for use with the on-site program developed by the Padilla Bay National Esturine Research Reserve (Washington). The guide…

  2. 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.

  3. Fecal indicator bacteria at Havana Bay

    International Nuclear Information System (INIS)

    Lopez Perez, Lisse; Gomez D'Angelo, Yamiris; Beltran Gonzalez, Jesus; Alvarez Valiente, Reinaldo

    2013-01-01

    Aims: Fecal indicator bacteria concentrations were evaluated in Havana Bay. Methods: Concentrations of traditional fecal indicator bacteria were calculated between April 2010 and February 2011, by MPN methods. Concentrations of thermo tolerant coliform (CTT), Escherichia coli, fecal streptococci (EF), intestinal enterococci (ENT) in seawater, and Clostridium perfringens in sediment surface, were determined. Results: CTT and E. coli levels were far above Cuban water quality standard for indirect contact with water, showing the negative influence of sewage and rivers on the bay. The EF and ENT were measured during sewage spills at the discharge site and they were suitable indicators of fecal contamination, but these indicators didn't show the same behavior in other selected sites. This result comes from its well-known inactivation by solar light in tropical zones and the presumable presence of humid acids in the waters of the bay. Conclusion: Fecal indicator bacteria and its statistical relationships reflect recent and chronic fecal contamination at the bay and near shores.

  4. Tortuguero Bay [Puerto Rico] environmental studies

    International Nuclear Information System (INIS)

    Wood, E.D.; Youngbluth, M.J.; Nutt, M.E.; Yoshioka, P.; Canoy, M.J.

    1975-01-01

    Site selection surveys and environmental research studies of seven coastal sites in Puerto Rico for construction of power generating facilities were carried out. Data are presented on the physical, chemical, and geological parameters of the Tortuguero Bay site, and the ecological parameters of zooplankton, benthic invertebrates, plant and fish communities. (U.S.)

  5. Roebuck Bay Invertebrate and bird Mapping 2006

    NARCIS (Netherlands)

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

  6. Morphological features in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, K.V.L.N.S.; Ramana, M.V.; Subrahmanyam, V.; Krishna, K.S.; Ramprasad, T.; Desa, M.

    history of the Fan. After India's soft collision with the Eurasian plate, these events may have played a critical role in shaping various morphological features since late Eocene in the Bay of Bengal. The present 12 kHz Echo sounder data collected along...

  7. 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

  8. Saginaw Bay, MI LiDAR

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — TASK NAME:(NRCS) Saginaw Bay, MI LiDAR LiDAR Data Acquisition and Processing Production Task USGS Contract No. G10PC00057 Task Order No. G11PD01254 Woolpert Order...

  9. Empirical Bayes Approaches to Multivariate Fuzzy Partitions.

    Science.gov (United States)

    Woodbury, Max A.; Manton, Kenneth G.

    1991-01-01

    An empirical Bayes-maximum likelihood estimation procedure is presented for the application of fuzzy partition models in describing high dimensional discrete response data. The model describes individuals in terms of partial membership in multiple latent categories that represent bounded discrete spaces. (SLD)

  10. Divergent Priors and well Behaved Bayes Factors

    NARCIS (Netherlands)

    R.W. Strachan (Rodney); H.K. van Dijk (Herman)

    2011-01-01

    textabstractDivergent priors are improper when defined on unbounded supports. Bartlett's paradox has been taken to imply that using improper priors results in ill-defined Bayes factors, preventing model comparison by posterior probabilities. However many improper priors have attractive properties

  11. 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...

  12. Pb’s high sedimentation inside the bay mouth of Jiaozhou Bay

    Science.gov (United States)

    Yang, Dongfang; Miao, Zhenqing; Huang, Xinmin; Wei, Linzhen; Feng, Ming

    2017-12-01

    Sedimentation is one of the key environmental behaviors of pollutants in the ocean. This paper analyzed the seasonal and temporal variations of Pb’s sedimentation process in Jiaozhou Bay in 1987. Results showed that Pb contents in bottom waters in Jiaozhou Bay in May, July and November 1987 were 1.87-2.60 μg L-1, 15.11-19.68 μg L-1 and 11.08-15.18 μg L-1, and the pollution levels of Pb in May, July and November 1987 were slight, heavy and heavy, respectively. In May 1987, there was low sedimentation process in waters in the outside of the bay mouth, yet were high sedimentation process in waters in the middle and inside of the bay mouth. In July and November 1987, there was low sedimentation process in waters in the outside of the bay mouth, yet were high sedimentation process in waters in the inside of the bay mouth. The seasonal-temporal variation of sedimentation processes of Pb were determined by the variations of sources input and the vertical water’s effect.

  13. 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.

  14. 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

  15. Rapid Crustal Uplift at Birch Bay, Washington

    Science.gov (United States)

    Sherrod, B. L.; Kelsey, H. M.; Blakely, R. J.

    2010-12-01

    Geomorphology and coastal marsh stratigraphy suggest late Holocene uplift of the shoreline at Birch Bay, located northwest of Bellingham, Washington, during an earthquake on a shallow fault. LiDAR images show a raised, late Holocene shoreline along Birch Bay, with ~1 m of elevation difference between the modern shoreline and the inferred paleoshoreline. Commercial seismic reflection images reveal an anticline in Tertiary and possibly Quaternary deposits underlying Birch Bay. NW-trending magnetic anomalies are likely associated with the Birch Bay anticline and other nearby structures. Taken together, the geophysical data and lidar images suggest uplift of young deposits along a NW-trending blind reverse fault. Stratigraphy from Terrell Creek marsh, located just south of Birch Bay, shows freshwater peat buried by lower intertidal muds, indicating local submergence ~1300 yr BP. Stratigraphy of a 70-cm sediment core from Birch Bay marsh, sitting astride the anticline imaged with seismic reflection data, shows mud buried by detrital peat. One radiocarbon age from the core places the abrupt change from mud to peat prior to 1520-1700 yr BP. We divide fossil diatom assemblages straddling the mud-peat contact at Birch Bay into three zones. The oldest zone consists primarily of intertidal and marine diatoms, dominated by Paralia sulcata, Scoleoneis tumida, Grammataphora oceanica, and Gyrosigma balticum. An intermediate zone, beginning at the sharp contact between mud and overlying peat, consists of a mixture of brackish marsh and freshwater species, dominated by Diploneis interrupta, with lesser amounts of Aulacoseira sp., Pinnularia viridis, Eunotia pectinalis, and Paralia sulcata. A third and youngest zone lies in the upper half of the peat and is dominated by poorly preserved freshwater diatoms, mostly Aulacoseira cf. crassapuntata, Pinnularia viridis, P. maior, Eunotia pectinalis, and E. praerupta. Paleoecological inferences, based on distributions of modern diatoms

  16. POTENTIAL HAZARDS OF SEDIMENT IN KENDARI BAY, SOUTHEAST SULAWESI

    Directory of Open Access Journals (Sweden)

    Nur Adi Kristanto

    2017-07-01

    Full Text Available Kendari bay is located in front of Kendari city. There are two harbors in the inner part of bay which very important to support economic activities such as shipping and passenger transportation. The result of coastal characteristic mapping and physical oceanography survey show various coastal morphology, vegetation, weathering processes, sedimentation, currents, and water depth and sea floor morphology. Kendari bay is an enclosed bay; the area is wide in the inner part and narrow in mouth of bay (outlet, the morphology look like a bottle’s neck. Numerous mouth rivers are concentrate around the bay. The rivers load material from land since erosion on land is intensive enough. There is indication that sediment supplies from land trough river mouth not equivalent with outlet capacity. Sediment load is trapped in the inner bay caused the outlet morphology. So high sediment rate play an important role in the process of shallow of water depth in Kendari bay. This condition make the Kendari bay is a prone area of sediment hazard due to height rate of sedimentary process. Therefore, to anticipate the hazards, precaution should be taken related to the Kendari bay as the center of activities in southeast of Sulawesi. The further survey is needed such as marine geotechnique and on land environmental to collect data, which can be used as database for development planning. Key words: Potential hazard, sediment, Kendari Bay Teluk

  17. Holocene evolution of Apalachicola Bay, Florida

    Science.gov (United States)

    Osterman, L.E.; Twichell, D.C.; Poore, R.Z.

    2009-01-01

    A program of geophysical mapping and vibracoring was conducted to better understand the geologic evolution of Apalachicola Bay. Analyses of the geophysical data and sediment cores along with age control provided by 34 AMS 14C dates on marine shells and wood reveal the following history. As sea level rose in the early Holocene, fluvial deposits filled the Apalachicola River paleochannel, which extended southward under the central part of the bay and seaward across the continental shelf. Sediments to either side of the paleochannel contain abundant wood fragments, with dates documenting that those areas were forested at 8,000 14C years b.p. As sea level continued to rise, spits formed of headland prodelta deposits. Between ???6,400 and ???2,500 14C years b.p., an Apalachicola prodelta prograded and receded several times across the inner shelf that underlies the western part of the bay. An eastern deltaic lobe was active for a shorter time, between ???5,800 and 5,100 14C years b.p. Estuarine benthic foraminiferal assemblages occurred in the western bay as early as 6,400 14C years b.p., and indicate that there was some physical barrier to open-ocean circulation and shelf species established by that time. It is considered that shoals formed in the region of the present barrier islands as the rising sea flooded an interstream divide. Estuarine conditions were established very early in the post-glacial flooding of the bay. ?? 2009 US Government.

  18. Topobathymetric model of Mobile Bay, Alabama

    Science.gov (United States)

    Danielson, Jeffrey J.; Brock, John C.; Howard, Daniel M.; Gesch, Dean B.; Bonisteel-Cormier, Jamie M.; Travers, Laurinda J.

    2013-01-01

    Topobathymetric Digital Elevation Models (DEMs) are a merged rendering of both topography (land elevation) and bathymetry (water depth) that provides a seamless elevation product useful for inundation mapping, as well as for other earth science applications, such as the development of sediment-transport, sea-level rise, and storm-surge models. This 1/9-arc-second (approximately 3 meters) resolution model of Mobile Bay, Alabama was developed using multiple topographic and bathymetric datasets, collected on different dates. The topographic data were obtained primarily from the U.S. Geological Survey (USGS) National Elevation Dataset (NED) (http://ned.usgs.gov/) at 1/9-arc-second resolution; USGS Experimental Advanced Airborne Research Lidar (EAARL) data (2 meters) (http://pubs.usgs.gov/ds/400/); and topographic lidar data (2 meters) and Compact Hydrographic Airborne Rapid Total Survey (CHARTS) lidar data (2 meters) from the U.S. Army Corps of Engineers (USACE) (http://www.csc.noaa.gov/digitalcoast/data/coastallidar/). Bathymetry was derived from digital soundings obtained from the National Oceanic and Atmospheric Administration’s (NOAA) National Geophysical Data Center (NGDC) (http://www.ngdc.noaa.gov/mgg/geodas/geodas.html) and from water-penetrating lidar sources, such as EAARL and CHARTS. Mobile Bay is ecologically important as it is the fourth largest estuary in the United States. The Mobile and Tensaw Rivers drain into the bay at the northern end with the bay emptying into the Gulf of Mexico at the southern end. Dauphin Island (a barrier island) and the Fort Morgan Peninsula form the mouth of Mobile Bay. Mobile Bay is 31 miles (50 kilometers) long by a maximum width of 24 miles (39 kilometers) with a total area of 413 square miles (1,070 square kilometers). The vertical datum of the Mobile Bay topobathymetric model is the North American Vertical Datum of 1988 (NAVD 88). All the topographic datasets were originally referenced to NAVD 88 and no transformations

  19. New insights into the distribution and evolution of the Cenozoic Tan-Lu Fault Zone in the Liaohe sub-basin of the Bohai Bay Basin, eastern China

    Science.gov (United States)

    Huang, Lei; Liu, Chi-yang; Xu, Chang-gui; Wu, Kui; Wang, Guang-yuan; Jia, Nan

    2018-01-01

    As the largest strike-slip fault system in eastern China, the northeast-trending Tan-Lu Fault Zone (TLFZ) is a significant tectonic element contributing to the Mesozoic-Cenozoic regional geologic evolution of eastern Asia, as well as to the formation of ore deposits and oilfields. Because of the paucity of data, its distribution and evolutionary history in the offshore Liaohe sub-basin of the northern Bohai Bay Basin (BBB) are still poorly understood. Investigations of the strike-slip fault system in the western portion of the offshore Liaohe sub-basin via new seismic data provide us with new insights into the characteristics of the Cenozoic TLFZ. Results of this study show that Cenozoic dextral strike-slip faults occurred near the center of the Liaoxi graben in the offshore Liaohe sub-basin; these strike-slip faults connect with their counterparts to the north, the western part of the onshore Liaohe sub-basin, and have similar characteristics to those in other areas of the BBB in terms of kinematics, evolutionary history, and distribution; consequently, these faults are considered as the western branch of the TLFZ. All strike-slip faults within the Liaoxi graben merge at depth with a central subvertical basement fault induced by the reactivation of a pre-existing strike-slip basement fault, the pre-Cenozoic TLFZ. Data suggest that the TLFZ across the whole Liaohe sub-basin comprises two branches and that the Cenozoic distribution of this system was inherited from the pre-Cenozoic TLFZ. This characteristic distribution might be possessed by the whole TLFZ, thus the new understandings about the distribution and evolutionary model of the TLFZ in this study can be inferred in many research fields along the whole fault zone, such as regional geology, ore deposits, petroleum exploration and earthquake hazard.

  20. Bird surveys at McKinley Bay and Hutchinson Bay, Northwest Territories, in 1990

    Energy Technology Data Exchange (ETDEWEB)

    Cornish, B J; Dickson, D L; Dickson, H L

    1991-03-01

    Monitoring surveys of bird abundance and distribution were conducted in 1990 at McKinley Bay in the Northwest Territories, the site of a winter harbour for drillships and the proposed location for a major year-round support base for oil and gas exploration. Primary objectives of the survey were to determine whether diving duck numbers had changed since the initial phase of the study from 1981-1985, and to provide additional baseline data on natural annual fluctuations in diving duck numbers. Three aerial surveys at each bay were carried out using techniques identical to those in previous years. On 5 August 1990, when survey conditions were considered best of the three surveys, more than twice as many diving ducks were found in McKinley Bay and Hutchinson Bay than on average during the five years of 1981-1985. Old squaw and scooters comprised ca 90% of the diving ducks observed, and both species showed significant increases in numbers. The increase in abundance of diving ducks was likely unrelated to industrial activity in the area since a similar increase occurred in the control area, Hutchinson Bay. Many factors, including both environmental factors such as those affecting nesting success and timing of the moult, and factors related to the survey methods, could be involved in causing the large fluctuations observed. 9 refs., 8 figs., 10 tabs.

  1. Bird surveys at McKinley Bay and Hutchinson Bay, Northwest Territories, in 1990

    International Nuclear Information System (INIS)

    Cornish, B.J.; Dickson, D.L.; Dickson, H.L.

    1991-01-01

    Monitoring surveys of bird abundance and distribution were conducted in 1990 at McKinley Bay in the Northwest Territories, the site of a winter harbour for drillships and the proposed location for a major year-round support base for oil and gas exploration. Primary objectives of the survey were to determine whether diving duck numbers had changed since the initial phase of the study from 1981-1985, and to provide additional baseline data on natural annual fluctuations in diving duck numbers. Three aerial surveys at each bay were carried out using techniques identical to those in previous years. On 5 August 1990, when survey conditions were considered best of the three surveys, more than twice as many diving ducks were found in McKinley Bay and Hutchinson Bay than on average during the five years of 1981-1985. Old squaw and scooters comprised ca 90% of the diving ducks observed, and both species showed significant increases in numbers. The increase in abundance of diving ducks was likely unrelated to industrial activity in the area since a similar increase occurred in the control area, Hutchinson Bay. Many factors, including both environmental factors such as those affecting nesting success and timing of the moult, and factors related to the survey methods, could be involved in causing the large fluctuations observed. 9 refs., 8 figs., 10 tabs

  2. 76 FR 9593 - Proclaiming Certain Lands, Reykers Acquisition, as an Addition to the Bay Mills Indian...

    Science.gov (United States)

    2011-02-18

    ..., as an Addition to the Bay Mills Indian Reservation for the Bay Mills Indian Community of Michigan..., more or less, to be added to the Bay Mills Indian Reservation for the Bay Mills Indian Community of... the land described below. The land was proclaimed to be an addition to the Bay Mills Indian...

  3. Urban Noise Modelling in Boka Kotorska Bay

    Directory of Open Access Journals (Sweden)

    Aleksandar Nikolić

    2014-04-01

    Full Text Available Traffic is the most significant noise source in urban areas. The village of Kamenari in Boka Kotorska Bay is a site where, in a relatively small area, road traffic and sea (ferry traffic take place at the same time. Due to the specificity of the location, i.e. very rare synergy of sound effects of road and sea traffic in the urban area, as well as the expressed need for assessment of noise level in a simple and quick way, a research was conducted, using empirical methods and statistical analysis methods, which led to the creation of acoustic model for the assessment of equivalent noise level (Leq. The developed model for noise assessment in the Village of Kamenari in Boka Kotorska Bay quite realistically provides data on possible noise levels at the observed site, with very little deviations in relation to empirically obtained values.

  4. New and Improved Results from Daya Bay

    CERN Multimedia

    CERN. Geneva

    2017-01-01

    Despite the great progress achieved in the last decades, neutrinos remain among the least understood fundamental particles to have been experimentally observed. The Daya Bay Reactor Neutrino Experiment consists of eight identically designed detectors placed underground at different baselines from three groups of nuclear reactors in China, a configuration that is ideally suited for studying the properties of these elusive particles. In this talk I will review the improved results released last summer by the Daya Bay collaboration. These results include (i) a precision measurement of the θ13 mixing angle and the effective mass splitting in the electron antineutrino disappearance channel with a dataset comprising more than 2.5 million antineutrino interactions, (ii) a high-statistics measurement of the absolute flux and spectrum of reactor-produced electron antineutrinos, and (iii) a search for light sterile neutrino mixing performed with more than three times the statistics of the previous result. I w...

  5. The Bay of Pigs: Revisiting Two Museums

    Directory of Open Access Journals (Sweden)

    Peter Read

    2007-08-01

    Full Text Available The Museum of Playa Giron (the Bay of Pigs in the region of Cienega De Zapata, Cuba, celebrates the repulse of Brigade 2506 as the first reverse of US imperialism on the American continents. The equivalent Brigade 2506 Museum in Miami, dedicated to and maintained by the members of Brigade 2506, celebrates defeat at the Bay of Pigs as moral victory for the Cuban exiles. The forces were indeed implacable foes. Yet between the museums can be detected some curious similarities. Both present the common theme of the confrontation between forces of good and evil. Both celebrate the philosophy that dying for one’s country is the greatest good a citizen may achieve. Both museums fly the common Cuban flag. Both museums identify a common enemy: the United States of America. This article, by comparing the displays in the two museums, analyses some cultural elements of what, despite decades of separation, in some ways remains a common Cuban culture.

  6. Thatcher Bay, Washington, Nearshore Restoration Assessment

    Science.gov (United States)

    Breems, Joel; Wyllie-Echeverria, Sandy; Grossman, Eric E.; Elliott, Joel

    2009-01-01

    The San Juan Archipelago, located at the confluence of the Puget Sound, the Straits of Juan de Fuca in Washington State, and the Straits of Georgia, British Columbia, Canada, provides essential nearshore habitat for diverse salmonid, forage fish, and bird populations. With 408 miles of coastline, the San Juan Islands provide a significant portion of the available nearshore habitat for the greater Puget Sound and are an essential part of the regional efforts to restore Puget Sound (Puget Sound Shared Strategy 2005). The nearshore areas of the San Juan Islands provide a critical link between the terrestrial and marine environments. For this reason the focus on restoration and conservation of nearshore habitat in the San Juan Islands is of paramount importance. Wood-waste was a common by-product of historical lumber-milling operations. To date, relatively little attention has been given to the impact of historical lumber-milling operations in the San Juan Archipelago. Thatcher Bay, on Blakely Island, located near the east edge of the archipelago, is presented here as a case study on the restoration potential for a wood-waste contaminated nearshore area. Case study components include (1) a brief discussion of the history of milling operations. (2) an estimate of the location and amount of the current distribution of wood-waste at the site, (3) a preliminary examination of the impacts of wood-waste on benthic flora and fauna at the site, and (4) the presentation of several restoration alternatives for the site. The history of milling activity in Thatcher Bay began in 1879 with the construction of a mill in the southeastern part of the bay. Milling activity continued for more than 60 years, until the mill closed in 1942. Currently, the primary evidence of the historical milling operations is the presence of approximately 5,000 yd3 of wood-waste contaminated sediments. The distribution and thickness of residual wood-waste at the site was determined by using sediment

  7. Daya Bay Antineutrino Detector Gas System

    OpenAIRE

    Band, H. R.; Cherwinka, J. J.; Chu, M-C.; Heeger, K. M.; Kwok, M. W.; Shih, K.; Wise, T.; Xiao, Q.

    2012-01-01

    The Daya Bay Antineutrino Detector gas system is designed to protect the liquid scintillator targets of the antineutrino detectors against degradation and contamination from exposure to ambient laboratory air. The gas system is also used to monitor the leak tightness of the antineutrino detector assembly. The cover gas system constantly flushes the gas volumes above the liquid scintillator with dry nitrogen to minimize oxidation of the scintillator over the five year lifetime of the experimen...

  8. Monterey Bay Aquarium Volunteer Guide Scheduling Analysis

    Science.gov (United States)

    2014-12-01

    TERMS 15. NUMBER OF Monterey Bay Aquarium, linear programing, network design, multi commodity flow, resilience PAGES 17. SECURITY 18. SECURITY...Volunteers fill many roles that include Aquarium guides, information desk attendants, divers, and animal caregivers . Julie Packard, Executive Director of...further analyze the resiliency of the shifts to changes in staffing levels caused by no-shows or drop-ins. 3 While the guide program managers have

  9. 33 CFR 165.1182 - Safety/Security Zone: San Francisco Bay, San Pablo Bay, Carquinez Strait, and Suisun Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety/Security Zone: San... Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY... Areas Eleventh Coast Guard District § 165.1182 Safety/Security Zone: San Francisco Bay, San Pablo Bay...

  10. Cosmogenic neutron production at Daya Bay

    Science.gov (United States)

    An, F. P.; Balantekin, A. B.; Band, H. R.; Bishai, M.; Blyth, S.; Cao, D.; Cao, G. F.; Cao, J.; Chan, Y. L.; Chang, J. F.; Chang, Y.; Chen, H. S.; Chen, S. M.; Chen, Y.; Chen, Y. X.; Cheng, J.; Cheng, Z. K.; Cherwinka, J. J.; Chu, M. C.; Chukanov, A.; Cummings, J. P.; Ding, Y. Y.; Diwan, M. V.; Dolgareva, M.; Dove, J.; Dwyer, D. A.; Edwards, W. R.; Gill, R.; Gonchar, M.; Gong, G. H.; Gong, H.; Grassi, M.; Gu, W. Q.; Guo, L.; Guo, X. H.; Guo, Y. H.; Guo, Z.; Hackenburg, R. W.; Hans, S.; He, M.; Heeger, K. M.; Heng, Y. K.; Higuera, A.; Hsiung, Y. B.; Hu, B. Z.; Hu, T.; Huang, H. X.; Huang, X. T.; Huang, Y. B.; Huber, P.; Huo, W.; Hussain, G.; Jaffe, D. E.; Jen, K. L.; Ji, X. L.; Ji, X. P.; Jiao, J. B.; Johnson, R. A.; Jones, D.; Kang, L.; Kettell, S. H.; Khan, A.; Koerner, L. W.; Kohn, S.; Kramer, M.; Kwok, M. W.; Langford, T. J.; Lau, K.; Lebanowski, L.; Lee, J.; Lee, J. H. C.; Lei, R. T.; Leitner, R.; Leung, J. K. C.; Li, C.; Li, D. J.; Li, F.; Li, G. S.; Li, Q. J.; Li, S.; Li, S. C.; Li, W. D.; Li, X. N.; Li, X. Q.; Li, Y. F.; Li, Z. B.; Liang, H.; Lin, C. J.; Lin, G. L.; Lin, S.; Lin, S. K.; Lin, Y.-C.; Ling, J. J.; Link, J. M.; Littenberg, L.; Littlejohn, B. R.; Liu, J. C.; Liu, J. L.; Loh, C. W.; Lu, C.; Lu, H. Q.; Lu, J. S.; Luk, K. B.; Ma, X. B.; Ma, X. Y.; Ma, Y. Q.; Malyshkin, Y.; Martinez Caicedo, D. A.; McDonald, K. T.; McKeown, R. D.; Mitchell, I.; Nakajima, Y.; Napolitano, J.; Naumov, D.; Naumova, E.; Ochoa-Ricoux, J. P.; Olshevskiy, A.; Pan, H.-R.; Park, J.; Patton, S.; Pec, V.; Peng, J. C.; Pinsky, L.; Pun, C. S. J.; Qi, F. Z.; Qi, M.; Qian, X.; Qiu, R. M.; Raper, N.; Ren, J.; Rosero, R.; Roskovec, B.; Ruan, X. C.; Steiner, H.; Sun, J. L.; Tang, W.; Taychenachev, D.; Treskov, K.; Tsang, K. V.; Tse, W.-H.; Tull, C. E.; Viaux, N.; Viren, B.; Vorobel, V.; Wang, C. H.; Wang, M.; Wang, N. Y.; Wang, R. G.; Wang, W.; Wang, X.; Wang, Y. F.; Wang, Z.; Wang, Z.; Wang, Z. M.; Wei, H. Y.; Wen, L. J.; Whisnant, K.; White, C. G.; Wise, T.; Wong, H. L. H.; Wong, S. C. F.; Worcester, E.; Wu, C.-H.; Wu, Q.; Wu, W. J.; Xia, D. M.; Xia, J. K.; Xing, Z. Z.; Xu, J. L.; Xu, Y.; Xue, T.; Yang, C. G.; Yang, H.; Yang, L.; Yang, M. S.; Yang, M. T.; Yang, Y. Z.; Ye, M.; Ye, Z.; Yeh, M.; Young, B. L.; Yu, Z. Y.; Zeng, S.; Zhan, L.; Zhang, C.; Zhang, C. C.; Zhang, H. H.; Zhang, J. W.; Zhang, Q. M.; Zhang, R.; Zhang, X. T.; Zhang, Y. M.; Zhang, Y. M.; Zhang, Y. X.; Zhang, Z. J.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, J.; Zhou, L.; Zhuang, H. L.; Zou, J. H.; Daya Bay Collaboration

    2018-03-01

    Neutrons produced by cosmic ray muons are an important background for underground experiments studying neutrino oscillations, neutrinoless double beta decay, dark matter, and other rare-event signals. A measurement of the neutron yield in the three different experimental halls of the Daya Bay Reactor Neutrino Experiment at varying depth is reported. The neutron yield in Daya Bay's liquid scintillator is measured to be Yn=(10.26 ±0.86 )×10-5 , (10.22 ±0.87 )×10-5 , and (17.03 ±1.22 )×10-5 μ-1 g-1 cm2 at depths of 250, 265, and 860 meters-water-equivalent. These results are compared to other measurements and the simulated neutron yield in Fluka and Geant4. A global fit including the Daya Bay measurements yields a power law coefficient of 0.77 ±0.03 for the dependence of the neutron yield on muon energy.

  11. Daya Bay Antineutrino Detector gas system

    Science.gov (United States)

    Band, H. R.; Cherwinka, J. J.; Chu, M.-C.; Heeger, K. M.; Kwok, M. W.; Shih, K.; Wise, T.; Xiao, Q.

    2012-11-01

    The Daya Bay Antineutrino Detector gas system is designed to protect the liquid scintillator targets of the antineutrino detectors against degradation and contamination from exposure to ambient laboratory air. The gas system is also used to monitor the leak tightness of the antineutrino detector assembly. The cover gas system constantly flushes the gas volumes above the liquid scintillator with dry nitrogen to minimize oxidation of the scintillator over the five year lifetime of the experiment. This constant flush also prevents the infiltration of radon or other contaminants into these detecting liquids keeping the internal backgrounds low. Since the Daya Bay antineutrino detectors are immersed in the large water pools of the muon veto system, other gas volumes are needed to protect vital detector cables or gas lines. These volumes are also purged with dry gas. Return gas is monitored for oxygen content and humidity to provide early warning of potentially damaging leaks. The design and performance of the Daya Bay Antineutrino Detector gas system is described.

  12. An overview of San Francisco Bay PORTS

    Science.gov (United States)

    Cheng, Ralph T.; McKinnie, David; English, Chad; Smith, Richard E.

    1998-01-01

    The Physical Oceanographic Real-Time System (PORTS) provides observations of tides, tidal currents, and meteorological conditions in real-time. The San Francisco Bay PORTS (SFPORTS) is a decision support system to facilitate safe and efficient maritime commerce. In addition to real-time observations, SFPORTS includes a nowcast numerical model forming a San Francisco Bay marine nowcast system. SFPORTS data and nowcast numerical model results are made available to users through the World Wide Web (WWW). A brief overview of SFPORTS is presented, from the data flow originated at instrument sensors to final results delivered to end users on the WWW. A user-friendly interface for SFPORTS has been designed and implemented. Appropriate field data analysis, nowcast procedures, design and generation of graphics for WWW display of field data and nowcast results are presented and discussed. Furthermore, SFPORTS is designed to support hazardous materials spill prevention and response, and to serve as resources to scientists studying the health of San Francisco Bay ecosystem. The success (or failure) of the SFPORTS to serve the intended user community is determined by the effectiveness of the user interface.

  13. Whose Bay Street? Competing Narratives of Nassau's City Centre

    Directory of Open Access Journals (Sweden)

    Nona Patara Martin

    2009-05-01

    Full Text Available Bay Street has always been at the centre of commercial, cultural and political life in the Bahama Islands. It also acts as a gateway for millions of tourists who come to Nassau, the Bahamian capital, via cruise ships every year. Not surprisingly, Bahamians and non-Bahamians have widely divergent impressions of Bay Street. The need to accommodate the tourists who are critical to the Bahamian economy has meant that Bay Street, despite its deep social significance for Bahamians, has increasingly become a tourist space. With reference to the ‘sense of place’ and place attachment literature, this paper traces the transformation of Bay Street and attempts to tease out the most obvious tensions between the Bay Street that Bahamians experience and Bay Street as a port of call.

  14. Phytoplankton growth, dissipation, and succession in estuarine environments. [Chesapeake Bay

    Energy Technology Data Exchange (ETDEWEB)

    Seliger, H H

    1976-01-01

    Two major advances in a study of phytoplankton ecology in the Chesapeake Bay are reported. The annual subsurface transport of a dinoflagellate species (Prorocentrum mariae labouriae) from the mouth of the bay a distance northward of 120 nautical miles to the region of the Bay Bridge was followed. Prorocentrum is a major seasonal dinoflagellate in the Chespeake Bay and annually has been reported to form mahogany tides, dense reddish-brown patches, in the northern bay beginning in late spring and continuing through the summer. Subsequent to this annual appearance the Prorocentrum spread southward and into the western tributary estuaries. The physiological behavioral characteristics of the Prorocentrum were correlated with the physical water movements in the bay. A phytoplankton cage technique for the measurement in situ of the growth rates of natural mixed populations is described. (CH)

  15. Geochemistry of sediments in the Back Bay and Yellowknife Bay of the Great Slave Lake

    International Nuclear Information System (INIS)

    Mudroch, A.; Joshi, S.R.; Sutherland, D.; Mudroch, P.; Dickson, K.M.

    1989-01-01

    Gold mining activities have generated wastes with high concentrations of arsenic and zinc in the vicinity of Yellowknife, Northwest Territories, Canada. Some of the waste material has been discharged into Yellowknife Bay of Great Slave Lake. Concentrations of arsenic and zinc were determined in sediment cores collected at the depositional areas of Yellowknife Bay. Sedimentation rates were estimated using two different radiometric approaches: the depth profiles of cesium 137 and lead 210. Geochemical analysis of the sediment cores indicated input of similar material into sampling areas over the past 50 yr. Age profiles of the sediment constructed from the radionuclide measurements were used to determine historical trends of arsenic and zinc inputs into Yellowknife Bay. The historical record was in good agreement with implemented remedial actions and the usage patterns of both elements. 16 refs., 6 figs., 3 tabs

  16. Spatial-temporal migration laws of Cd in Jiaozhou Bay

    Science.gov (United States)

    Yang, Dongfang; Li, Haixia; Zhang, Xiaolong; Wang, Qi; Miao, Zhenqing

    2018-02-01

    Many marine bays have been polluted by various pollutants, and understanding the migration laws is essential to scientific research and pollution control. This paper analyzed the spatial and temporal migration laws of Cd in waters in Jiaozhou Bay during 1979—1983. Results showed that there were twenty spatial-temporal migration law for the migration processes of Cd. These laws were helpful for better understanding the migration of Cd in marine bay, providing basis for scientific research and pollution control.

  17. Organic Matter Remineralization Predominates Phosphorus Cycling in the Mid-Bay Sediments in the Chesapeake Bay

    Energy Technology Data Exchange (ETDEWEB)

    Sunendra, Joshi R.; Kukkadapu, Ravi K.; Burdige, David J.; Bowden, Mark E.; Sparks, Donald L.; Jaisi, Deb P.

    2015-05-19

    The Chesapeake Bay, the largest and most productive estuary in the US, suffers from varying degrees of water quality issues fueled by both point and non–point source nutrient sources. Restoration of the bay is complicated by the multitude of nutrient sources, their variable inputs and hydrological conditions, and complex interacting factors including climate forcing. These complexities not only restrict formulation of effective restoration plans but also open up debates on accountability issues with nutrient loading. A detailed understanding of sediment phosphorus (P) dynamics enables one to identify the exchange of dissolved constituents across the sediment- water interface and aid to better constrain mechanisms and processes controlling the coupling between the sediments and the overlying waters. Here we used phosphate oxygen isotope ratios (δ18Op) in concert with sediment chemistry, XRD, and Mössbauer spectroscopy on the sediment retrieved from an organic rich, sulfidic site in the meso-haline portion of the mid-bay to identify sources and pathway of sedimentary P cycling and to infer potential feedback effect on bottom water hypoxia and surface water eutrophication. Isotope data indicate that the regeneration of inorganic P from organic matter degradation (remineralization) is the predominant, if not sole, pathway for authigenic P precipitation in the mid-bay sediments. We interpret that the excess inorganic P generated by remineralization should have overwhelmed any bottom-water and/or pore-water P derived from other sources or biogeochemical processes and exceeded saturation with respect to authigenic P precipitation. It is the first research that identifies the predominance of remineralization pathway against remobilization (coupled Fe-P cycling) pathway in the Chesapeake Bay. Therefore, these results are expected to have significant implications for the current understanding of P cycling and benthic-pelagic coupling in the bay, particularly on the

  18. Upgrade of Daya Bay full scope simulator

    International Nuclear Information System (INIS)

    2006-01-01

    Daya Bay full scope simulator was manufactured by French THOMSON Company in earlier 1990s. It was put into operation in August 1992, one year before the plant's unit-1 was commissioned. During nearly 10 years, the Daya Bay simulator was used to train the control room operators. As many as 220 operators obtained their operator licenses or senior operators licenses. The Daya Bay simulator made a great contribution to the plant's operation. 2) Owing to the limitation of simulation technology and computer capacity in that age, Daya Bay simulator had its deficiencies from the beginning, making maintenance difficult, gradually bringing more and more impact on operator training. - Bad performance: The main computer was the Gould CONCEPT 32/67. Its calculation speed is quite low and memory very limited. Even in the normal operation mode, the average CPU load was up to 80%. The simulation fidelity and scope were not sufficient, which could not meet the deep level of training demand. Many special plant scenarios were not simulated; therefore it was not possible to undertake the verification exercises for the corresponding plant operations. - Poor maintainability: - In hardware aspect, due to that Gould CONCEPT 32/67 is with multi-board architecture. Thousands of tiny connection pins between boards and chasses was the weak link, after many times board plug in-out repair the connection became worse and worse. In addition, the spare parts are difficult to order. Computer crashes happened very often. Each time, the failures each took a few hours, even a few days to fix. - In software aspect, simulation modules suspension, OUT OF TIME error and software breakdown were often occurring. To restart the system took over half an hour each time, which seriously interrupted normal training. - In software maintenance aspect, most modules are manually coded and the development tools are difficult to use. Less than 10% of modifications related to the plant upgrade could be implemented on

  19. Delineation of marsh types from Corpus Christi Bay, Texas, to Perdido Bay, Alabama, in 2010

    Science.gov (United States)

    Enwright, Nicholas M.; Hartley, Stephen B.; Couvillion, Brady R.; Michael G. Brasher,; Jenneke M. Visser,; Michael K. Mitchell,; Bart M. Ballard,; Mark W. Parr,; Barry C. Wilson,

    2015-07-23

    Coastal zone managers and researchers often require detailed information regarding emergent marsh vegetation types (that is, fresh, intermediate, brackish, and saline) for modeling habitat capacities and needs of marsh dependent taxa (such as waterfowl and alligator). Detailed information on the extent and distribution of emergent marsh vegetation types throughout the northern Gulf of Mexico coast has been historically unavailable. In response, the U.S. Geological Survey, in collaboration with the Gulf Coast Joint Venture, the University of Louisiana at Lafayette, Ducks Unlimited, Inc., and the Texas A&M University-Kingsville, produced a classification of emergent marsh vegetation types from Corpus Christi Bay, Texas, to Perdido Bay, Alabama.

  20. PENERAPAN ALGORITMA NAIVE BAYES UNTUK MENGKLASIFIKASI DATA NASABAH ASURANSI

    Directory of Open Access Journals (Sweden)

    Bustami Bustami

    2014-01-01

    Full Text Available Data mining adalah teknik yang memanfaatkan data dalam jumlah yang besar untuk memperoleh informasi berharga yang sebelumnya tidak diketahui dan dapat dimanfaatkan untuk pengambilan keputusan penting. Pada penelitian ini, penulis berusaha menambang data (data mining nasabah sebuah perusahaan asuransi untuk mengetahui lancar, kurang lancar atau tidak lancarnya nasabah tersebut. Data yang ada dianalisis menggunakan algoritma Naive Bayes. Naive Bayes merupakan salah satu meode pada probabilistic reasoning. Algoritma Naive Bayes bertujuan untuk melakukan klasifikasi data pada kelas tertentu, kemudian pola tersebut dapat digunakan untuk memperkirakan nasabah yang bergabung, sehingga perusahaan bisa mengambil keputusan menerima atau menolak calon nasabah tersebut. Kata Kunci : data mining, asuransi, klasifikasi, algoritma Naive Bayes

  1. Heavy metals in superficial sediment of Algiers Bay

    International Nuclear Information System (INIS)

    Benamar, M.A.; Toumert, C.L.; Chaouch, L.; Bacha, L.; Tobbeche, S.

    1996-01-01

    Sediment samples were collected in 33 stations from the bay of Algiers for the potential sources of pollution. the analyses were made x-ray fluorescence (XRF) and atomic absorption spectrometry (AAS) the results give information about level of concentrations morphology of the bay (funnel form of bay). only Co,Mn,Fe, and Cd present a particular repartition (unrelated to the sedimentary facies). the level pollution bu heavy metals of the bottom sediments in algiers bay have been compared with those of Surkouk considered as a region with low anthropogenic activities

  2. MODELING THE 1958 LITUYA BAY MEGA-TSUNAMI, II

    Directory of Open Access Journals (Sweden)

    Charles L. Mader

    2002-01-01

    Full Text Available Lituya Bay, Alaska is a T-Shaped bay, 7 miles long and up to 2 miles wide. The two arms at the head of the bay, Gilbert and Crillon Inlets, are part of a trench along the Fairweather Fault. On July 8, 1958, an 7.5 Magnitude earthquake occurred along the Fairweather fault with an epicenter near Lituya Bay.A mega-tsunami wave was generated that washed out trees to a maximum altitude of 520 meters at the entrance of Gilbert Inlet. Much of the rest of the shoreline of the Bay was denuded by the tsunami from 30 to 200 meters altitude.In the previous study it was determined that if the 520 meter high run-up was 50 to 100 meters thick, the observed inundation in the rest of Lituya Bay could be numerically reproduced. It was also concluded that further studies would require full Navier-Stokes modeling similar to those required for asteroid generated tsunami waves.During the Summer of 2000, Hermann Fritz conducted experiments that reproduced the Lituya Bay 1958 event. The laboratory experiments indicated that the 1958 Lituya Bay 524 meter run-up on the spur ridge of Gilbert Inlet could be caused by a landslide impact.The Lituya Bay impact landslide generated tsunami was modeled with the full Navier- Stokes AMR Eulerian compressible hydrodynamic code called SAGE with includes the effect of gravity.

  3. Heme oxygenase-1 mediates BAY 11-7085 induced ferroptosis.

    Science.gov (United States)

    Chang, Ling-Chu; Chiang, Shih-Kai; Chen, Shuen-Ei; Yu, Yung-Luen; Chou, Ruey-Hwang; Chang, Wei-Chao

    2018-03-01

    Ferroptosis is a form of oxidative cell death and has become a chemotherapeutic target for cancer treatment. BAY 11-7085 (BAY), which is a well-known IκBα inhibitor, suppressed viability in cancer cells via induction of ferroptotic death in an NF-κB-independent manner. Reactive oxygen species scavenging, relief of lipid peroxidation, replenishment of glutathione and thiol-containing agents, as well as iron chelation, rescued BAY-induced cell death. BAY upregulated a variety of Nrf2 target genes related to redox regulation, particularly heme oxygenase-1 (HO-1). Studies with specific inhibitors and shRNA interventions suggested that the hierarchy of induction is Nrf2-SLC7A11-HO-1. SLC7A11 inhibition by erastin, sulfasalazine, or shRNA interference sensitizes BAY-induced cell death. Overexperession of SLC7A11 attenuated BAY-inhibited cell viability. The ferroptotic process induced by hHO-1 overexpression further indicated that HO-1 is a key mediator of BAY-induced ferroptosis that operates through cellular redox regulation and iron accumulation. BAY causes compartmentalization of HO-1 into the nucleus and mitochondrion, and followed mitochondrial dysfunctions, leading to lysosome targeting for mitophagy. In this study, we first discovered that BAY induced ferroptosis via Nrf2-SLC7A11-HO-1 pathway and HO-1 is a key mediator by responding to the cellular redox status. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Florida Bay: A history of recent ecological changes

    Science.gov (United States)

    Fourqurean, J.W.; Robblee, M.B.

    1999-01-01

    Florida Bay is a unique subtropical estuary at the southern tip of the Florida peninsula. Recent ecological changes (seagrass die-off, algal blooms, increased turbidity) to the Florida Bay ecosystem have focused the attention of the public, commercial interests, scientists, and resource managers on the factors influencing the structure and function of Florida Bay. Restoring Florida Bay to some historic condition is the goal of resource managers, but what is not clear is what an anthropogenically-unaltered Florida Bay would look like. While there is general consensus that human activities have contributed to the changes occurring in the Florida Bay ecosystem, a high degree of natural system variability has made elucidation of the links between human activity and Florida Bay dynamics difficult. Paleoecological analyses, examination of long-term datasets, and directed measurements of aspects of the ecology of Florida Bay all contribute to our understanding of the behavior of the bay, and allow quantification of the magnitude of the recent ecological changes with respect to historical variability of the system.

  5. 南海西部油田钡锶防垢剂挤注体系%Squeeze Injection System of Barium Strontium Sulfate Scale Inhibitors in the South China Sea West Oilfield

    Institute of Scientific and Technical Information of China (English)

    孙爱平; 贺建英; 李飞; 王林海; 李强; 方明新

    2017-01-01

    In the process of water injection development of western of the south China sea oilfield, the serious barium/strontium sulfate scales have occurred in the oil wells in the middle block of the oilfield, due to the incompatibility between injected sea water with rich SO2-4 and formation water with rich Ba2+ and Sr2+. The experiment was conducted for four kinds of organic phosphonate scale inhibitors in terms of chemical compatibility of barium strontium sulfate scale inhibitors, static inhibition efficiency, stability and dynamic adsorption/desorption of the scale inhibitors required for squeeze treatment. The experimental results showed that: by adjusting the pH chemical compatibility of HYZ-101 scale inhibitor was better at 120 ℃; when concentration ≥5 mg/L, static inhibition efficiency>90%;under the 120 ℃ heat treatment after 30 d, the drop of inhibition efficiency is very small, still > 90%; the results of core flood experiment showed that at low pH the adsorption/desorption performance of scale inhibitor was better than at high pH. The reasonable scale inhibitor HYZ-101 was selected to solve the problem of the western of the south China sea oilfield.%南海西部油田注水开发中富含SO.2-4的海水与含有Ba.2+、Sr.2+的地层水不配伍,导致近井地带硫酸钡锶垢结垢现象严重.根据防垢剂挤注技术的具体要求,进行了钡锶防垢剂配伍性实验、静态防垢率实验、热稳定性能实验以及岩心动态吸附/解吸附实验,对四种主要成分为HEDP与PESA的复合防垢剂进行评价,结果表明:在120 ℃下,防垢剂HYZ-101通过调节pH值之后配伍性较好;当质量浓度≥5 mg/L时,其静态防垢率>90%;在120 ℃下热处理30 d后,防垢率下降幅度很小,防垢率仍>90%;动态吸附/解吸附实验表明,低pH下防垢剂的吸附/解吸附性能较高pH下更好.因此优选出防垢剂HYZ-101来解决南海西部油田结垢问题.

  6. Sediment depositional environment in some bays in Central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Rajamanickam, G.V.; Gujar, A.R.

    negatively and Ratnagiri Bay positively skewed. Kalbadevi sediments show high kurtosis values while those of Mirya Bay show medium and Ratnagiri Bay low values. Bivariant plots between various textural parameters predict mixed environments, viz. for Kalbadevi...

  7. On watermass mixing ratios and regenerated silicon in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, D.P.; Sarma, V.V.; Rao, V.S.; Sudhakar, U.; Gupta, G.V.M.

    Regeneration of silicon on mixing in the Bay of Bengal have been computed from six water masses [Bay of Bengal low saline water (BBLS), Bay of Bengal subsurface water (BBSS), northern southeast high salinity water (NSEHS), north Indian intermediate...

  8. Diagnosis of potential stressors adversely affecting benthic invertebrate communities in Greenwich Bay, Rhode Island, USA

    Science.gov (United States)

    Greenwich Bay is an urbanized embayment of Narragansett Bay potentially impacted by multiple stressors. The present study identified the important stressors affecting Greenwich Bay benthic fauna. First, existing data and information were used to confirm that the waterbody was imp...

  9. Color Shaded-Relief and Surface-Classification Maps of the Fish Creek Area, Harrison Bay Quadrangle, Northern Alaska

    Science.gov (United States)

    Mars, John L.; Garrity, Christopher P.; Houseknecht, David W.; Amoroso, Lee; Meares, Donald C.

    2007-01-01

    Introduction The northeastern part of the National Petroleum Reserve in Alaska (NPRA) has become an area of active petroleum exploration during the past five years. Recent leasing and exploration drilling in the NPRA requires the U.S. Bureau of Land Management (BLM) to manage and monitor a variety of surface activities that include seismic surveying, exploration drilling, oil-field development drilling, construction of oil-production facilities, and construction of pipelines and access roads. BLM evaluates a variety of permit applications, environmental impact studies, and other documents that require rapid compilation and analysis of data pertaining to surface and subsurface geology, hydrology, and biology. In addition, BLM must monitor these activities and assess their impacts on the natural environment. Timely and accurate completion of these land-management tasks requires elevation, hydrologic, geologic, petroleum-activity, and cadastral data, all integrated in digital formats at a higher resolution than is currently available in nondigital (paper) formats. To support these land-management tasks, a series of maps was generated from remotely sensed data in an area of high petroleum-industry activity (fig. 1). The maps cover an area from approximately latitude 70?00' N. to 70?30' N. and from longitude 151?00' W. to 153?10' W. The area includes the Alpine oil field in the east, the Husky Inigok exploration well (site of a landing strip) in the west, many of the exploration wells drilled in NPRA since 2000, and the route of a proposed pipeline to carry oil from discovery wells in NPRA to the Alpine oil field. This map area is referred to as the 'Fish Creek area' after a creek that flows through the region. The map series includes (1) a color shaded-relief map based on 5-m-resolution data (sheet 1), (2) a surface-classification map based on 30-m-resolution data (sheet 2), and (3) a 5-m-resolution shaded relief-surface classification map that combines the shaded

  10. Influence of net freshwater supply on salinity in Florida Bay

    Science.gov (United States)

    Nuttle, William K.; Fourqurean, James W.; Cosby, Bernard J.; Zieman, Joseph C.; Robblee, Michael B.

    2000-01-01

    An annual water budget for Florida Bay, the large, seasonally hypersaline estuary in the Everglades National Park, was constructed using physically based models and long‐term (31 years) data on salinity, hydrology, and climate. Effects of seasonal and interannual variations of the net freshwater supply (runoff plus rainfall minus evaporation) on salinity variation within the bay were also examined. Particular attention was paid to the effects of runoff, which are the focus of ambitious plans to restore and conserve the Florida Bay ecosystem. From 1965 to 1995 the annual runoff from the Everglades into the bay was less than one tenth of the annual direct rainfall onto the bay, while estimated annual evaporation slightly exceeded annual rainfall. The average net freshwater supply to the bay over a year was thus approximately zero, and interannual variations in salinity appeared to be affected primarily by interannual fluctuations in rainfall. At the annual scale, runoff apparently had little effect on the bay as a whole during this period. On a seasonal basis, variations in rainfall, evaporation, and runoff were not in phase, and the net freshwater supply to the bay varied between positive and negative values, contributing to a strong seasonal pattern in salinity, especially in regions of the bay relatively isolated from exchanges with the Gulf of Mexico and Atlantic Ocean. Changes in runoff could have a greater effect on salinity in the bay if the seasonal patterns of rainfall and evaporation and the timing of the runoff are considered. One model was also used to simulate spatial and temporal patterns of salinity responses expected to result from changes in net freshwater supply. Simulations in which runoff was increased by a factor of 2 (but with no change in spatial pattern) indicated that increased runoff will lower salinity values in eastern Florida Bay, increase the variability of salinity in the South Region, but have little effect on salinity in the Central

  11. 77 FR 15359 - Availability of Seats for the Thunder Bay National Marine Sanctuary Advisory Council

    Science.gov (United States)

    2012-03-15

    ... Bay National Marine Sanctuary, 500 W. Fletcher Street, Alpena, Michigan 49707. Completed applications... Coordinator, Thunder Bay National Marine. Sanctuary, 500 W. Fletcher Street, Alpena, Michigan 49707, (989) 356...

  12. A Bayes linear Bayes method for estimation of correlated event rates.

    Science.gov (United States)

    Quigley, John; Wilson, Kevin J; Walls, Lesley; Bedford, Tim

    2013-12-01

    Typically, full Bayesian estimation of correlated event rates can be computationally challenging since estimators are intractable. When estimation of event rates represents one activity within a larger modeling process, there is an incentive to develop more efficient inference than provided by a full Bayesian model. We develop a new subjective inference method for correlated event rates based on a Bayes linear Bayes model under the assumption that events are generated from a homogeneous Poisson process. To reduce the elicitation burden we introduce homogenization factors to the model and, as an alternative to a subjective prior, an empirical method using the method of moments is developed. Inference under the new method is compared against estimates obtained under a full Bayesian model, which takes a multivariate gamma prior, where the predictive and posterior distributions are derived in terms of well-known functions. The mathematical properties of both models are presented. A simulation study shows that the Bayes linear Bayes inference method and the full Bayesian model provide equally reliable estimates. An illustrative example, motivated by a problem of estimating correlated event rates across different users in a simple supply chain, shows how ignoring the correlation leads to biased estimation of event rates. © 2013 Society for Risk Analysis.

  13. 75 FR 54771 - Safety Zone; Thunder on the Bay, Chesapeake Bay, Buckroe Beach Park, Hampton, VA

    Science.gov (United States)

    2010-09-09

    ... navigable waters of the Chesapeake Bay within the area bounded by a 210-foot radius circle centered on... are technical standards (e.g., specifications of materials, performance, design, or operation; test... cumulatively have a significant effect on the human environment. This rule is categorically excluded, under...

  14. 78 FR 27989 - Bandon Marsh, Nestucca Bay, and Siletz Bay National Wildlife Refuges, Coos, Tillamook, and...

    Science.gov (United States)

    2013-05-13

    ....S. Mail: Oregon Coast National Wildlife Refuge Complex, 2127 SE Marine Science Drive, Newport, OR... W. Lowe, Project Leader, Oregon Coast National Wildlife Refuge Complex, 2127 SE Marine Science Drive... Service would also remodel the north bay of the maintenance shop to accommodate two offices: one for...

  15. Management case study: Tampa Bay, Florida

    Science.gov (United States)

    Morrison, Gerold; Greening, Holly; Yates, Kimberly K.; Wolanski, Eric; McLusky, Donald S.

    2011-01-01

    Tampa Bay, Florida, USA, is a shallow, subtropical estuary that experienced severe cultural eutrophication between the 1940s and 1980s, a period when the human population of its watershed quadrupled. In response, citizen action led to the formation of a public- and private-sector partnership (the Tampa Bay Estuary Program), which adopted a number of management objectives to support the restoration and protection of the bay’s living resources. These included numeric chlorophyll a and water-clarity targets, as well as long-term goals addressing the spatial extent of seagrasses and other selected habitat types, to support estuarine-dependent faunal guilds. Over the past three decades, nitrogen controls involving sources such as wastewater treatment plants, stormwater conveyance systems, fertilizer manufacturing and shipping operations, and power plants have been undertaken to meet these and other management objectives. Cumulatively, these controls have resulted in a 60% reduction in annual total nitrogen (TN) loads relative to earlier worse-case (latter 1970s) conditions. As a result, annual water-clarity and chlorophyll a targets are currently met in most years, and seagrass cover measured in 2008 was the highest recorded since 1950. Factors that have contributed to the observed improvements in Tampa Bay over the past several decades include the following: (1) Development of numeric, science-based water-quality targets to meet a long-term goal of restoring seagrass acreage to 1950s levels. Empirical and mechanistic models found that annual average chlorophyll a concentrations were a primary manageable factor affecting light attenuation. The models also quantified relationships between TN loads, chlorophyll a concentrations, light attenuation, and fluctuations in seagrass cover. The availability of long-term monitoring data, and a systematic process for using the data to evaluate the effectiveness of management actions, has allowed managers to track progress and

  16. Metode Pengambilan Keputusan Dengan Teorema Bayes

    OpenAIRE

    Sihombing, Richardo Tober

    2010-01-01

    Decision making is very important for the men. The purpose of decision making is to survive or continuing life. Such of the case in organization or companies, decision making is very important and was needed by manager. Decision making is easy to decide if the data or information complete and under certainty. But if the data isn’t complete, so that uncertainty factor may arise in probabilities. In this study, Bayes Theorm is write down exactly the probability to infer decision making. Thus, i...

  17. Minimum relative entropy, Bayes and Kapur

    Science.gov (United States)

    Woodbury, Allan D.

    2011-04-01

    The focus of this paper is to illustrate important philosophies on inversion and the similarly and differences between Bayesian and minimum relative entropy (MRE) methods. The development of each approach is illustrated through the general-discrete linear inverse. MRE differs from both Bayes and classical statistical methods in that knowledge of moments are used as ‘data’ rather than sample values. MRE like Bayes, presumes knowledge of a prior probability distribution and produces the posterior pdf itself. MRE attempts to produce this pdf based on the information provided by new moments. It will use moments of the prior distribution only if new data on these moments is not available. It is important to note that MRE makes a strong statement that the imposed constraints are exact and complete. In this way, MRE is maximally uncommitted with respect to unknown information. In general, since input data are known only to within a certain accuracy, it is important that any inversion method should allow for errors in the measured data. The MRE approach can accommodate such uncertainty and in new work described here, previous results are modified to include a Gaussian prior. A variety of MRE solutions are reproduced under a number of assumed moments and these include second-order central moments. Various solutions of Jacobs & van der Geest were repeated and clarified. Menke's weighted minimum length solution was shown to have a basis in information theory, and the classic least-squares estimate is shown as a solution to MRE under the conditions of more data than unknowns and where we utilize the observed data and their associated noise. An example inverse problem involving a gravity survey over a layered and faulted zone is shown. In all cases the inverse results match quite closely the actual density profile, at least in the upper portions of the profile. The similar results to Bayes presented in are a reflection of the fact that the MRE posterior pdf, and its mean

  18. Monitoring of bird abundance and distribution at McKinley Bay and Hutchison Bay, Northwest Territories, 1981 to 1993

    Energy Technology Data Exchange (ETDEWEB)

    Cornish, B J; Dickson, D L

    1994-04-01

    McKinley Bay has been identified as a preferred site for a harbor to support oil and gas production in the Beaufort Sea. As the bay is a molting area for several species of diving duck, a study was initiated to monitor the effect of harbor development on birds using the bay. Baseline information on the natural annual fluctuations in the number of birds were collected for nine years at McKinley Bay and eight years at neighboring Hutchinson Bay, an area chosen as the control. The final report of the predevelopment phase of the monitoring study is presented, including results of the 1993 surveys and a summary of results of all years of surveys. There were significantly more diving ducks in McKinley Bay in early August 1990 to 1993, on average, than from 1981 to 1985. No statistically significant change in total diving ducks was noted at Hutchinson Bay. Numbers of species of divers varied substantially between years at the two bays but not to the same degree. Significantly more Pacific loons, red-throated loons, and northern pintails were recorded in the 1990-1993 surveys at McKinley Bay than in earlier surveys. Potential explanations for the large between-year fluctuations in diving duck numbers are discussed. The variations may be due to bird responses to changes in the physical environment or related to the limitations of the aerial survey techniques used. Because of the large natural fluctuations in numbers of molting diving ducks using these bays in early August, it will be difficult to detect future impacts of industrial disturbance, even when sources of survey bias are minimized. It is concluded that aerial surveys of molting diving ducks in the two bays are unsuitable for monitoring the effects of industrial development. 41 refs., 7 figs., 23 tabs.

  19. 33 CFR 80.1430 - Kaneohe Bay, Oahu, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Kaneohe Bay, Oahu, HI. 80.1430 Section 80.1430 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1430 Kaneohe Bay, Oahu, HI. A straight line...

  20. 46 CFR 7.110 - Mamala Bay, HI.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Mamala Bay, HI. 7.110 Section 7.110 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC BOUNDARY LINES Hawaii § 7.110 Mamala Bay, HI. A line drawn from Barbers Point Light to Diamond Head Light. Pacific Coast ...

  1. 33 CFR 80.1420 - Mamala Bay, Oahu, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Mamala Bay, Oahu, HI. 80.1420 Section 80.1420 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1420 Mamala Bay, Oahu, HI. A line drawn from...

  2. Baseline surveys of Lac Bay benthic and fish communities, Bonaire

    NARCIS (Netherlands)

    Debrot, A.O.; Hylkema, A.; Vogelaar, W.; Meesters, H.W.G.; Engel, M.S.; Leon, R.; Prud'homme van Reine, W.F.; Nagelkerken, I.

    2012-01-01

    Lac Bay is a clear-water, 5 m deep shallow tropical lagoon of 7 km2 opening onto the wave and wind exposed east coast of the island of Bonaire, southern Caribbean. Over the last decades land reclamation by mangroves in Lac has been expanding the surface of turbid, saline backwaters into the bay at

  3. Optimasi Naive Bayes Dengan Pemilihan Fitur Dan Pembobotan Gain Ratio

    Directory of Open Access Journals (Sweden)

    I Guna Adi Socrates

    2016-03-01

    Full Text Available Naïve Bayes merupakan salah satu metode data mining yang umum digunakan dalam klasifikasi dokumen berbasis text. Kelebihan dari metode ini adalah algoritma yang sederhana dengan  kompleksitas  perhitungan  yang  rendah.  Akan  tetapi,  pada  metode  Naïve  Bayes terdapat kelemahan dimana sifat independensi dari fitur Naïve Bayes tidak dapat selalu diterapkan sehingga akan berpengaruh pada tingkat akurasi perhitungan. Maka dari itu, metode Naïve Bayes perlu dioptimasi dengan cara pemberian bobot mengunakan Gain Ratio. Namun, pemberian bobot pada Naïve Bayes menimbulkan permasalahan pada penghitungan probabilitas setiap    dokumen, dimana fitur  yang tidak  merepresentasikan kelas  yang diuji banyak muncul sehingga terjadi kesalahan klasifikasi. Oleh karena itu, pembobotan Naïve Bayes   masih   belum   optimal.   Paper   ini mengusulkan  optimasi  metode   Naïve   Bayes mengunakan pembobotan Gain Ratio yang ditambahkan dengan metode pemilihan fitur pada kasus klasifikasi teks. Hasil penelitian ini menunjukkan bahwa optimasi metode Naïve Bayes menggunakan pemilihan fitur dan pembobotan menghasilkan akurasi sebesar 94%.

  4. Gamma Activation Analysis in the Havana Bay superficial sediments

    International Nuclear Information System (INIS)

    Lopez, N.; Gelen, A.; Diaz Riso, O.; Manso, M.V.; Simon, M.J.; Maslov, A.G.; Gustova, M.V.; Beltran, J.; Soto, J.

    2003-01-01

    A preliminary study of 26 elements of Havana Bay superficial sediments were made using Gamma Activation Analysis. Samples from five zones of Havana Bay were analyzed. The results show a close interrelation between the concentration levels of the studied elements and the contaminant sources

  5. 75 FR 8396 - Izembek National Wildlife Refuge, Cold Bay, Alaska

    Science.gov (United States)

    2010-02-24

    ...] Izembek National Wildlife Refuge, Cold Bay, Alaska AGENCY: U.S. Fish and Wildlife Service, Interior..., we will hold public scoping meetings in King Cove, Cold Bay, Sand Point, and Nelson Lagoon in Alaska... Aleutian arc chain of volcanoes. Landforms include mountains, active volcanoes, U-shaped valleys, glacial...

  6. Inputs and spatial distribution patterns of Cr in Jiaozhou Bay

    Science.gov (United States)

    Yang, Dongfang; Miao, Zhenqing; Huang, Xinmin; Wei, Linzhen; Feng, Ming

    2018-03-01

    Cr pollution in marine bays has been one of the critical environmental issues, and understanding the input and spatial distribution patterns is essential to pollution control. In according to the source strengths of the major pollution sources, the input patterns of pollutants to marine bay include slight, moderate and heavy, and the spatial distribution are corresponding to three block models respectively. This paper analyzed input patterns and distributions of Cr in Jiaozhou Bay, eastern China based on investigation on Cr in surface waters during 1979-1983. Results showed that the input strengths of Cr in Jiaozhou Bay could be classified as moderate input and slight input, and the input strengths were 32.32-112.30 μg L-1 and 4.17-19.76 μg L-1, respectively. The input patterns of Cr included two patterns of moderate input and slight input, and the horizontal distributions could be defined by means of Block Model 2 and Block Model 3, respectively. In case of moderate input pattern via overland runoff, Cr contents were decreasing from the estuaries to the bay mouth, and the distribution pattern was parallel. In case of moderate input pattern via marine current, Cr contents were decreasing from the bay mouth to the bay, and the distribution pattern was parallel to circular. The Block Models were able to reveal the transferring process of various pollutants, and were helpful to understand the distributions of pollutants in marine bay.

  7. San Francisco Bay Long Term Management Strategy for Dredging

    Science.gov (United States)

    The San Francisco Bay Long Term Management Strategy (LTMS) is a cooperative effort to develop a new approach to dredging and dredged material disposal in the San Francisco Bay area. The LTMS serves as the Regional Dredging Team for the San Francisco area.

  8. Tampa Bay Ecosystem Services Demonstration Pilot Phase 2 web site

    Science.gov (United States)

    The value of nature's benefits is difficult to consider in environmental decision-making since ecosystem goods and services are usually not well measured or quantified in economic terms. The Tampa Bay Estuary Program, Tampa Bay Regional Planning Council, the U.S. Environmental Pr...

  9. Neutron calibration sources in the Daya Bay experiment

    Energy Technology Data Exchange (ETDEWEB)

    Liu, J., E-mail: jianglai.liu@sjtu.edu.cn [Department of Physics, Shanghai Jiao Tong University, Shanghai (China); Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA (United States); Carr, R. [Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA (United States); Dwyer, D.A. [Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA (United States); Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Gu, W.Q. [Department of Physics, Shanghai Jiao Tong University, Shanghai (China); Li, G.S., E-mail: lgs1029@sjtu.edu.cn [Department of Physics, Shanghai Jiao Tong University, Shanghai (China); McKeown, R.D. [Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA (United States); Department of Physics, College of William and Mary, Williamsburg, VA (United States); Qian, X. [Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA (United States); Brookhaven National Laboratory, Upton, NY (United States); Tsang, R.H.M. [Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA (United States); Department of Physics and Astronomy, University of Alabama, Tuscaloosa, AL 35487 (United States); Wu, F.F. [Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA (United States); Zhang, C. [Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, CA (United States); Brookhaven National Laboratory, Upton, NY (United States)

    2015-10-11

    We describe the design and construction of the low rate neutron calibration sources used in the Daya Bay Reactor Anti-neutrino Experiment. Such sources are free of correlated gamma-neutron emission, which is essential in minimizing induced background in the anti-neutrino detector. The design characteristics have been validated in the Daya Bay anti-neutrino detector.

  10. Neutron calibration sources in the Daya Bay experiment

    International Nuclear Information System (INIS)

    Liu, J.; Carr, R.; Dwyer, D.A.; Gu, W.Q.; Li, G.S.; McKeown, R.D.; Qian, X.; Tsang, R.H.M.; Wu, F.F.; Zhang, C.

    2015-01-01

    We describe the design and construction of the low rate neutron calibration sources used in the Daya Bay Reactor Anti-neutrino Experiment. Such sources are free of correlated gamma-neutron emission, which is essential in minimizing induced background in the anti-neutrino detector. The design characteristics have been validated in the Daya Bay anti-neutrino detector

  11. Summer survival of Phytophthora ramorum in California bay laurel leaves

    Science.gov (United States)

    Elizabeth J. Fichtner; David M. Rizzo; Shannon C. Lynch; Jennifer Davidson; Gerri Buckles; Jennifer Parker

    2008-01-01

    Sudden oak death manifests as non-lethal foliar lesions on bay laurel (Umbellularia californica), which support sporulation and survival of Phytophthora ramorum in forest ecosystems. Infected bay laurel leaves are more likely to abscise than uninfected leaves, resulting in an accumulation of inoculum at the forest floor. The pathogen survives the dry...

  12. 33 CFR 110.120 - San Luis Obispo Bay, Calif.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false San Luis Obispo Bay, Calif. 110... ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.120 San Luis Obispo Bay, Calif. (a) Area A-1. Area A-1 is the water area bounded by the San Luis Obispo County wharf, the shoreline, a line drawn...

  13. 33 CFR 80.1130 - San Luis Obispo Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false San Luis Obispo Bay, CA. 80.1130 Section 80.1130 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1130 San Luis Obispo Bay, CA. A line drawn from...

  14. Intertidal sediments and benthic animals of Roebuck Bay, Western Australia

    NARCIS (Netherlands)

    Pepping, M.; Piersma, T.; Pearson, G.; Lavaleye, M.

    1999-01-01

    Roebuck Bay near Broome (NW Australia) is with itsextensive tidal flats one of the foremost internationallyimportant sites for shorebirds in the Asia-Pacificflyway system. It is home to 150,000 shorebirds (or‘waders’) in the nonbreeding season, which suggeststhat the intertidal flats of the bay have

  15. The changing ecology of Narragansett Bay as told by habitat

    Science.gov (United States)

    Narragansett Bay has changed in many ways over millennia due to natural and human forces, and the rate of this change increased greatly after European colonization. We evaluated distributions of three stressors and four habitats in eight subdivisions of the Bay for aspects of ec...

  16. Radionuclides in sediments from Port Phillip Bay, Australia

    International Nuclear Information System (INIS)

    Smith, J.D.; Tinker, R.A.; Towler, P.H.

    1998-01-01

    Full text: Sediment cores were collected from two sites in Port Phillip Bay, Australia, in 1994 and 1995. The concentration of 210 Pb and parameters including water content were measured. The sites chosen were near the centre of the bay where fine sediment accumulates, and towards the northern end of the bay closer to the mouth of the Yarra River. The mid-bay sediment had a high water content (about 1.8 g water per g dry sediment) and a supported 210 Pb activity of about 22 mBq per g of dry sediment. The sediments from further north in the bay were more consolidated, with a lower water content (about 0.6 g water per g dry sediment), and had a supported 210 Pb activity of about 6 mBq per g of dry sediment. Unsupported 210 Pb occurred to depths of about 10 cm in the mid-bay sediment and about 20 cm in sediment from further north in the bay. Models incorporating the water and 210 Pb contents of the sediments were used to calculate possible rates of sediment accumulation and mixing. The distribution of other radionuclides was used as an aid in understanding the sediment behaviour in Port Phillip Bay

  17. Sepetiba Bay: an integrated study of an harbour location

    International Nuclear Information System (INIS)

    Bandeira, J.V.; Aun, P.E.; Castro, J.O.N.M. de; Moreira, R.M.

    1984-01-01

    Several aspects of the construction of an iron-ore and coal terminal in Sepetiba bay (RJ, Brazil) in the region of south of Madeira Island, are presented. The studies include a general view of the geomorphology of the region, analyses of current measurements, water circulation and sedimentology of the bay by conventional methods and by radioactive tracers. (M.A.C.) [pt

  18. Field Exploration of Methane Seep Near Atqasuk

    Energy Technology Data Exchange (ETDEWEB)

    Katey Walter, Dennis Witmer, Gwen Holdmann

    2008-12-31

    Methane (CH{sub 4}) in natural gas is a major energy source in the U.S., and is used extensively on Alaska's North Slope, including the oilfields in Prudhoe Bay, the community of Barrow, and the National Petroleum Reserve, Alaska (NPRA). Smaller villages, however, are dependent on imported diesel fuel for both power and heating, resulting in some of the highest energy costs in the U.S. and crippling local economies. Numerous CH{sub 4} gas seeps have been observed on wetlands near Atqasuk, Alaska (in the NPRA), and initial measurements have indicated flow rates of 3,000-5,000 ft{sup 3} day{sup -1} (60-100 kg CH{sub 4} day{sup -1}). Gas samples collected in 1996 indicated biogenic origin, although more recent sampling indicated a mixture of biogenic and thermogenic gas. In this study, we (1) quantified the amount of CH{sub 4} generated by several seeps and evaluated their potential use as an unconventional gas source for the village of Atqasuk; (2) collected gas and analyzed its composition from multiple seeps several miles apart to see if the source is the same, or if gas is being generated locally from isolated biogenic sources; and (3) assessed the potential magnitude of natural CH{sub 4} gas seeps for future use in climate change modeling.

  19. Flow units classification for geostatisitical three-dimensional modeling of a non-marine sandstone reservoir: A case study from the Paleocene Funing Formation of the Gaoji Oilfield, east China

    Science.gov (United States)

    Zhang, Penghui; Zhang, Jinliang; Wang, Jinkai; Li, Ming; Liang, Jie; Wu, Yingli

    2018-05-01

    Flow units classification can be used in reservoir characterization. In addition, characterizing the reservoir interval into flow units is an effective way to simulate the reservoir. Paraflow units (PFUs), the second level of flow units, are used to estimate the spatial distribution of continental clastic reservoirs at the detailed reservoir description stage. In this study, we investigate a nonroutine methodology to predict the external and internal distribution of PFUs. The methodology outlined enables the classification of PFUs using sandstone core samples and log data. The relationships obtained between porosity, permeability and pore throat aperture radii (r35) values were established for core and log data obtained from 26 wells from the Funing Formation, Gaoji Oilfield, Subei Basin, China. The present study refines predicted PFUs at logged (0.125-m) intervals, whose scale is much smaller than routine methods. Meanwhile, three-dimensional models are built using sequential indicator simulation to characterize PFUs in wells. Four distinct PFUs are classified and located based on the statistical methodology of cluster analysis, and each PFU has different seepage ability. The results of this study demonstrate the obtained models are able to quantify reservoir heterogeneity. Due to different petrophysical characteristics and seepage ability, PFUs have a significant impact on the distribution of the remaining oil. Considering these allows a more accurate understanding of reservoir quality, especially within non-marine sandstone reservoirs.

  20. Hydrodynamics and water quality models applied to Sepetiba Bay

    Science.gov (United States)

    Cunha, Cynara de L. da N.; Rosman, Paulo C. C.; Ferreira, Aldo Pacheco; Carlos do Nascimento Monteiro, Teófilo

    2006-10-01

    A coupled hydrodynamic and water quality model is used to simulate the pollution in Sepetiba Bay due to sewage effluent. Sepetiba Bay has a complicated geometry and bottom topography, and is located on the Brazilian coast near Rio de Janeiro. In the simulation, the dissolved oxygen (DO) concentration and biochemical oxygen demand (BOD) are used as indicators for the presence of organic matter in the body of water, and as parameters for evaluating the environmental pollution of the eastern part of Sepetiba Bay. Effluent sources in the model are taken from DO and BOD field measurements. The simulation results are consistent with field observations and demonstrate that the model has been correctly calibrated. The model is suitable for evaluating the environmental impact of sewage effluent on Sepetiba Bay from river inflows, assessing the feasibility of different treatment schemes, and developing specific monitoring activities. This approach has general applicability for environmental assessment of complicated coastal bays.

  1. The effect of loss functions on empirical Bayes reliability analysis

    Directory of Open Access Journals (Sweden)

    Camara Vincent A. R.

    1998-01-01

    Full Text Available The aim of the present study is to investigate the sensitivity of empirical Bayes estimates of the reliability function with respect to changing of the loss function. In addition to applying some of the basic analytical results on empirical Bayes reliability obtained with the use of the “popular” squared error loss function, we shall derive some expressions corresponding to empirical Bayes reliability estimates obtained with the Higgins–Tsokos, the Harris and our proposed logarithmic loss functions. The concept of efficiency, along with the notion of integrated mean square error, will be used as a criterion to numerically compare our results. It is shown that empirical Bayes reliability functions are in general sensitive to the choice of the loss function, and that the squared error loss does not always yield the best empirical Bayes reliability estimate.

  2. Mangrove root communities in Jobos Bay

    International Nuclear Information System (INIS)

    Yoshioka, P.M.

    1975-01-01

    Based on the presence and absence of species, at least two major types of mangrove root communities exist in Jobos Bay. One community, occurring mainly along the Aguirre Ship Channel, is composed of species characteristic of coastal waters. Another occurring in Jobos Bay and in mangrove channels in the vinicity of Mar Negro Lagoon is characterized by embayment species. Water mass is the best single parameter which correlates with the different communities. In general, subtidal species are more susceptible to elevated temperatures than intertidal species and consequently will be the first affected. Because most of the predators and competitors are subtidal, the predation and competition which limit populations may be cut back. The effect will first be seen in increased populations of barnacles, because they are severely limited by predation and competition but are physiologically quite tolerant. The intertidal species should flourish (on a relative basis) and their vertical distributions should be extended downward. These effects are only primary. Many species which would do best in thermally altered situations are colonizing or fugitive species. It is unknown whether such an assemblage could persist with continued recruitment and growth of new individuals. The dominance of these colonizing or fugitive species may be only temporary, however, because blue-green algae are tolerant of elevated temperatures and have a negative effect on barnacle recruitment and growth. Consequently, blue-green algae may eventually dominate thermally affected mangrove roots

  3. 76 FR 70480 - Otay River Estuary Restoration Project, South San Diego Bay Unit of the San Diego Bay National...

    Science.gov (United States)

    2011-11-14

    ... River Estuary Restoration Project, South San Diego Bay Unit of the San Diego Bay National Wildlife...), intend to prepare an environmental impact statement (EIS) for the proposed Otay River Estuary Restoration... any one of the following methods. Email: [email protected] . Please include ``Otay Estuary NOI'' in the...

  4. ASTER Images San Francisco Bay Area

    Science.gov (United States)

    2000-01-01

    These images of the San Francisco Bay region were acquired on March 3, 2000 by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA's Terra satellite. Each covers an area 60 kilometers (37 miles) wide and 75 kilometers (47 miles) long. With its 14 spectral bands from the visible to the thermal infrared wavelength region, and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER will image the Earth for the next 6 years to map and monitor the changing surface of our planet.Upper Left: The color infrared composite uses bands in the visible and reflected infrared. Vegetation is red, urban areas are gray; sediment in the bays shows up as lighter shades of blue. Thanks to the 15 meter (50-foot) spatial resolution, shadows of the towers along the Bay Bridge can be seen.Upper right: A composite of bands in the short wave infrared displays differences in soils and rocks in the mountainous areas. Even though these regions appear entirely vegetated in the visible, enough surface shows through openings in the vegetation to allow the ground to be imaged.Lower left: This composite of multispectral thermal bands shows differences in urban materials in varying colors. Separation of materials is due to differences in thermal emission properties, analogous to colors in the visible.Lower right: This is a color coded temperature image of water temperature, derived from the thermal bands. Warm waters are in white and yellow, colder waters are blue. Suisun Bay in the upper right is fed directly from the cold Sacramento River. As the water flows through San Pablo and San Francisco Bays on the way to the Pacific, the waters warm up.Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) is one of five Earth-observing instruments launched December 18, 1999, on NASA's Terra satellite. The instrument was built by Japan's Ministry of International Trade and Industry. A joint U.S./Japan science team is responsible for

  5. Integrating science and resource management in Tampa Bay, Florida

    Science.gov (United States)

    Yates, Kimberly K.; Greening, Holly; Morrison, Gerold

    2011-01-01

    Tampa Bay is recognized internationally for its remarkable progress towards recovery since it was pronounced "dead" in the late 1970s. Due to significant efforts by local governments, industries and private citizens throughout the watershed, water clarity in Tampa Bay is now equal to what it was in 1950, when population in the watershed was less than one-quarter of what it is today. Seagrass extent has increased by more than 8,000 acres since the mid-1980s, and fish and wildlife populations are increasing. Central to this successful turn-around has been the Tampa Bay resource management community's long-term commitment to development and implementation of strong science-based management strategies. Research institutions and agencies, including Eckerd College, the Florida Wildlife Commission Fish and Wildlife Research Institute, Mote Marine Laboratory, National Oceanic and Atmospheric Administration, the Southwest Florida Water Management District, University of South Florida, U.S. Environmental Protection Agency, U.S. Geological Survey, local and State governments, and private companies contribute significantly to the scientific basis of our understanding of Tampa Bay's structure and ecological function. Resource management agencies, including the Tampa Bay Regional Planning Council's Agency on Bay Management, the Southwest Florida Water Management District's Surface Water Improvement and Management Program, and the Tampa Bay Estuary Program, depend upon this scientific basis to develop and implement regional adaptive management programs. The importance of integrating science with management has become fully recognized by scientists and managers throughout the region, State and Nation. Scientific studies conducted in Tampa Bay over the past 10–15 years are increasingly diverse and complex, and resource management programs reflect our increased knowledge of geology, hydrology and hydrodynamics, ecology and restoration techniques. However, a synthesis of this

  6. Bay breeze climatology at two sites along the Chesapeake bay from 1986-2010: Implications for surface ozone.

    Science.gov (United States)

    Stauffer, Ryan M; Thompson, Anne M

    Hourly surface meteorological measurements were coupled with surface ozone (O 3 ) mixing ratio measurements at Hampton, Virginia and Baltimore, Maryland, two sites along the Chesapeake Bay in the Mid-Atlantic United States, to examine the behavior of surface O 3 during bay breeze events and quantify the impact of the bay breeze on local O 3 pollution. Analyses were performed for the months of May through September for the years 1986 to 2010. The years were split into three groups to account for increasingly stringent environmental regulations that reduced regional emissions of nitrogen oxides (NO x ): 1986-1994, 1995-2002, and 2003-2010. Each day in the 25-year record was marked either as a bay breeze day, a non-bay breeze day, or a rainy/cloudy day based on the meteorological data. Mean eight hour (8-h) averaged surface O 3 values during bay breeze events were 3 to 5 parts per billion by volume (ppbv) higher at Hampton and Baltimore than on non-bay breeze days in all year periods. Anomalies from mean surface O 3 were highest in the afternoon at both sites during bay breeze days in the 2003-2010 study period. In conjunction with an overall lowering of baseline O 3 after the 1995-2002 period, the percentage of total exceedances of the Environmental Protection Agency (EPA) 75 ppbv 8-h O 3 standard that occurred on bay breeze days increased at Hampton for 2003-2010, while remaining steady at Baltimore. These results suggest that bay breeze circulations are becoming more important to causing exceedance events at particular sites in the region, and support the hypothesis of Martins et al. (2012) that highly localized meteorology increasingly drives air quality events at Hampton.

  7. Bayes Empirical Bayes Inference of Amino Acid Sites Under Positive Selection

    DEFF Research Database (Denmark)

    Yang, Ziheng; Wong, Wendy Shuk Wan; Nielsen, Rasmus

    2005-01-01

    , with > 1 indicating positive selection. Statistical distributions are used to model the variation in among sites, allowing a subset of sites to have > 1 while the rest of the sequence may be under purifying selection with ... probabilities that a site comes from the site class with > 1. Current implementations, however, use the naive EB (NEB) approach and fail to account for sampling errors in maximum likelihood estimates of model parameters, such as the proportions and ratios for the site classes. In small data sets lacking...... information, this approach may lead to unreliable posterior probability calculations. In this paper, we develop a Bayes empirical Bayes (BEB) approach to the problem, which assigns a prior to the model parameters and integrates over their uncertainties. We compare the new and old methods on real and simulated...

  8. Water quality of Tampa Bay, Florida, June 1972-May 1976

    Science.gov (United States)

    Goetz, Carole L.; Goodwin, Carl R.

    1980-01-01

    A comprehensive assessment of the water quality of Tampa Bay, Florida, was initiated in 1970 to provide background information to evaluate the effects of widening and deepening the ship channel to the port of Tampa. This report provides results of water-quality sampling in the bay from 1972 to 1976, prior to dredging. Measurements of temperature, dissolved oxygen, pH, turbidity, specific conductance, biochemical oxygen demand, and total organic carbon were made as well as measurements for several nutrient, metal, and pesticide parameters. Many parameters were measured at as many as three points in the vertical. These data indicate that Tampa Bay is well-mixed vertically with little density stratification. Time histories of average temperature, dissolved oxygen, pH, turbidity, specific conductance and nutrient values within four subareas of Tampa Bay are given to reveal seasonal or other trends during the period of record. Temperature, dissolved oxygen, pH, turbidity, specific conductance, nutrient, biochemical oxygen demand, total organic carbon, and metal data are also presented as areal distributions. Nutrient concentrations were generally higher in Hillsborough Bay than in other sub-areas of Tampa Bay. Biochemical oxygen demand, total organic carbon, and total organic nitrogen distribution patterns show regions of highest concentrations to be along bay shorelines near population centers. Of the metals analyzed, all were present in concentrations of less than 1 milligram per liter. (USGS)

  9. Studies of movement of sediments in Santos bay

    International Nuclear Information System (INIS)

    Bandeira, J.V.; Aun, P.E.; Bomtempo, V.L.; Salim, L.H.; Minardi, P.S.P.; Santos, J.A.

    1990-01-01

    In the years of 1973, 74, 80, 81 and 85 several studies were performed at Santos bay, using radioactive tracers, with the following main objectives: to evaluate the behaviour (on the bottom and in suspension) of the mixture of silt and clay which is dredged from the estuary and from its access channel and dumped at pre-determined sites, in the bay and surrounding regions, with the objective of optimizing dredging disposal operations; to quantify the movement of sandy sediments on the bottom, in 3 areas of the bay, in summer and winter conditions, to obtain pertinent information related to the siltation of the access channel. As results of these studies, it was found that: the ancient dumping site, near Itaipu Point, in the western limit of the bay, was inadequate, since the material could return to the bay and to the estuary. The dumping site was moved to a region at the south of Moela Island, located eastwards relative to the bay, which brought substantial economies in dredging works; the bottom sediment transport was quantified, following clouds of tagged materials for about 8 months, thus obtaining important conclusions about transport rates in different regions of the bay. An analysis of the intervening hydrodynamic agents is also presented. (author) (L.J.C.)

  10. 78 FR 34575 - Safety Zone; Bay Swim VI, Presque Isle Bay, Erie, PA

    Science.gov (United States)

    2013-06-10

    ... June 22, 2013, a large scale swimming event will be held on Presque Isle Bay near the Erie Yacht Club...'48.82'' W and extend in a straight line 1,000 feet wide to the Erie Yacht Club at position 42[deg]07... wide to the Erie Yacht Club at position 42[deg]07'21.74'' N, 80[deg]07'58.30'' W. (NAD 83) (b...

  11. Spatiotemporal appraisal of TBT contamination and imposex along a tropical bay (Todos os Santos Bay, Brazil).

    Science.gov (United States)

    Artifon, Vanda; Castro, Ítalo Braga; Fillmann, Gilberto

    2016-08-01

    A spatiotemporal evaluation of butyltin contamination was performed between 2010 and 2012 along Todos os Santos Bay (Northeast Brazil) using surface sediments, bivalve tissues (Anomalocardia brasiliana and Mytella guyanensis), and imposex occurrence (Stramonita rustica). The spatial study detected high tributyltin (TBT) levels (maximum values of 262 ng Sn g (-1) - 21,833 ng Sn g(-1) of total organic carbon - for surface sediments and 421 ng Sn g(-1) for bivalve tissues) in the innermost part of the bay. The TBT levels detected in M. guyanensis tissues might cause human health risk since local population consumes these organisms. These high concentrations observed in the bivalves might result in ingestions higher than the safe limits established by European Food Safety Authority (250 ng TBT kg(-1) day(-1)). Considering the temporal evaluation, no difference (p > 0.05) was observed between TBT concentrations in sediments obtained during the two sampling campaigns (2010/2011 and 2012). However, the increasing predominance of TBT metabolites (butyltin degradation index (BDI) >1) in more recent sediments indicates further degradation of old TBT inputs. In spite of that, recent inputs are still evident at this region. Nevertheless, a reduction of imposex parameters in S. rustica over the last decade suggests an overall decline in the TBT contamination, at least in the outermost and possible less impacted region of the bay. The TBT contamination is probably reducing due to the national and international legislative restrictions on the use of TBT as antifouling biocide. The contamination levels, however, are still relevant especially in the inner part of Todos os Santos Bay since they are above those that are likely to cause toxicity to the biota.

  12. Social and environmental impacts of the James Bay hydroelectric project

    International Nuclear Information System (INIS)

    Hornig, J.F.

    1999-01-01

    The book, which is an analysis and not an advocacy, examines the anatomy of the controversy that has swirled around the James Bay project - the La Grande and Great Whale projects combined - from the 1970s to the 1990s, and seeks, in the process, to determine whether there are lessons that can be learned from such an analysis that are applicable to other cases as well as to James Bay itself. The contributors are interested, at one and the same time, in finding ways to integrate the knowledge of natural scientists and social scientists to deepen the understanding of human/environment relations and to link science and policy to encourage a productive dialogue between practitioners and scholars in this increasingly important area of inquiry. The contributor's papers include the following: introduction to the issues; hydroelectric power development at James Bay: establishing a frame of reference; James Bay: environmental considerations for building large hydroelectric dams and reservoirs in Quebec; elevated mercury in fish as a result of the James Bay hydroelectric power development: perception and reality; the Cree people of James Bay: assessing the social impacts of hydroelectric dams and reservoirs; culture, social change, and Cree opposition to the James Bay hydroelectric development; and the impact of James Bay hydroelectric development on the art and craft of the James Bay Cree. The authors of the volume have attempted to stand back and examine just a few of these issues from the perspective of a variety of disciplines, and their purpose is to inform and stimulate thoughtful consideration by providing an overall perspective that might might serve to broaden the context in which specific issues can be debated. refs., 3 tabs., 5 figs

  13. Tectonic framework of the Hanoe Bay area, southern Baltic Sea

    International Nuclear Information System (INIS)

    Wannaes, K.O.; Floden, T.

    1994-06-01

    The tectonic framework and the general geologic development of the Hanoe Bay, from the Scanian coast in the west to south of Oeland in the east, has been investigated by means of reflection seismic methods. The Hanoe Bay is in this paper subdivided into four areas of different geologic settings. These are: 1) The Hanoe Bay slope, which forms a southward dipping continuation of the rigid Blekinge coastal plain. 2) The eastward dipping Kalmarsund Slope, which southwards from Oeland forms the western part of the Paleozoic Baltic Syneclise. 3) The Mesozoic Hanoe Bay Halfgraben, which forms the central and southern parts of the Hanoe Bay. The ongoing subsidence of the Halfgraben is estimated to be in the order of 20-60 m during the Quaternary. 4) The Yoldia Structural Element, which forms a deformed, tilted and possibly rotated block of Paleozoic bedrock located east of the Hanoe Bay Halfgraben. Two tectonic phases dominate the post-Paleozoic development of the Hanoe Bay, these are: 1) The Early Kimmerian phase, which initiated subsidence and reactivated older faults. 2) The Late Cretaceous phase, which is the main subsidence phase of the Hanoe Bay Halfgraben. The tectonic fault pattern of the Hanoe Bay is dominated by three directions, i.e. NW-SE, NE-SW and WNW-ESE. The two main tectonic elements of the area are the Kullen-Christiansoe Ridge System (NW-SE) and the Bornholm Gat Tectonic Zone (NE-SW). Sinistral strike-slip movements in order of 2-3 km are interpreted to have occurred along the Bornholm Gat Tectonic Zone during the late Cretaceous. 20 refs, 19 figs

  14. Are the Chesapeake Bay waters warming up

    International Nuclear Information System (INIS)

    Brady, D.K.

    1976-01-01

    Apparently significant trends within moderately long (50-year) series of meteorological or hydrological data should be regarded with suspicion until justified on the basis of much longer term information. Extra efforts should be directed toward securing the continuance of routine observations at stations where long data histories are already available and where the termination of such records might be regretted at some future time. Mean annual air and water temperatures at different sites may be quite highly correlated even when the points of measurement are very widely separated. The annual average water temperature at one station close to the Chesapeake Bay appears to be normally distributed with a standard deviation of 0.7 0 C about a stationary overall mean value of 14.6 0 C. Its 1000-year departure is +- 2.2 0 C

  15. bayesPop: Probabilistic Population Projections

    Science.gov (United States)

    Ševčíková, Hana; Raftery, Adrian E.

    2016-01-01

    We describe bayesPop, an R package for producing probabilistic population projections for all countries. This uses probabilistic projections of total fertility and life expectancy generated by Bayesian hierarchical models. It produces a sample from the joint posterior predictive distribution of future age- and sex-specific population counts, fertility rates and mortality rates, as well as future numbers of births and deaths. It provides graphical ways of summarizing this information, including trajectory plots and various kinds of probabilistic population pyramids. An expression language is introduced which allows the user to produce the predictive distribution of a wide variety of derived population quantities, such as the median age or the old age dependency ratio. The package produces aggregated projections for sets of countries, such as UN regions or trading blocs. The methodology has been used by the United Nations to produce their most recent official population projections for all countries, published in the World Population Prospects. PMID:28077933

  16. bayesPop: Probabilistic Population Projections

    Directory of Open Access Journals (Sweden)

    Hana Ševčíková

    2016-12-01

    Full Text Available We describe bayesPop, an R package for producing probabilistic population projections for all countries. This uses probabilistic projections of total fertility and life expectancy generated by Bayesian hierarchical models. It produces a sample from the joint posterior predictive distribution of future age- and sex-specific population counts, fertility rates and mortality rates, as well as future numbers of births and deaths. It provides graphical ways of summarizing this information, including trajectory plots and various kinds of probabilistic population pyramids. An expression language is introduced which allows the user to produce the predictive distribution of a wide variety of derived population quantities, such as the median age or the old age dependency ratio. The package produces aggregated projections for sets of countries, such as UN regions or trading blocs. The methodology has been used by the United Nations to produce their most recent official population projections for all countries, published in the World Population Prospects.

  17. IMAX films Destiny in Atlantis's payload bay

    Science.gov (United States)

    2001-01-01

    In the Payload Changeout Room at Launch Pad 39A, a film crew from IMAX prepares its 3-D movie camera to film the payload bay door closure on Atlantis. Behind them is the payload, the U.S. Laboratory Destiny, which will fly on mission STS-98, the seventh construction flight to the ISS. Destiny, a key element in the construction of the International Space Station, is 28 feet long and weighs 16 tons. This research and command-and-control center is the most sophisticated and versatile space laboratory ever built. It will ultimately house a total of 23 experiment racks for crew support and scientific research. Launch of Atlantis is Feb. 7 at 6:11 p.m. EST.

  18. Nonparametric Bayes Modeling of Multivariate Categorical Data.

    Science.gov (United States)

    Dunson, David B; Xing, Chuanhua

    2012-01-01

    Modeling of multivariate unordered categorical (nominal) data is a challenging problem, particularly in high dimensions and cases in which one wishes to avoid strong assumptions about the dependence structure. Commonly used approaches rely on the incorporation of latent Gaussian random variables or parametric latent class models. The goal of this article is to develop a nonparametric Bayes approach, which defines a prior with full support on the space of distributions for multiple unordered categorical variables. This support condition ensures that we are not restricting the dependence structure a priori. We show this can be accomplished through a Dirichlet process mixture of product multinomial distributions, which is also a convenient form for posterior computation. Methods for nonparametric testing of violations of independence are proposed, and the methods are applied to model positional dependence within transcription factor binding motifs.

  19. Muon Simulation at the Daya Bay SIte

    International Nuclear Information System (INIS)

    Mengyun, Guan; Jun, Cao; Changgen, Yang; Yaxuan, Sun; Luk, Kam-Biu

    2006-01-01

    With a pretty good-resolution mountain profile, we simulated the underground muon background at the Daya Bay site. To get the sea-level muon flux parameterization, a modification to the standard Gaisser's formula was introduced according to the world muon data. MUSIC code was used to transport muon through the mountain rock. To deploy the simulation, first we generate a statistic sample of sea-level muon events according to the sea-level muon flux distribution formula; then calculate the slant depth of muon passing through the mountain using an interpolation method based on the digitized data of the mountain; finally transport muons through rock to get underground muon sample, from which we can get results of muon flux, mean energy, energy distribution and angular distribution.

  20. Characterization of Dredged Sediments from Santander Bay

    International Nuclear Information System (INIS)

    Cortes, M.; Ibanez, R.; Viguri, J.R.; Irabien, A.

    1999-01-01

    The purpose of this study is the physico- chemical characterisation of Santander Bay (North Spain) inter-tidal sediments, with the determination of levels of selected organic compounds pollution. A sampling strategy has been developed based on characteristic parameters of the study. The physico-chemical seasonal characterisation of sediments has been performed by determination of waster content, Ph, density, humidity, lost on ignition (LOI), particle size distribution, and chemical analysis of three categories of organic compounds (VOCs,EOX and PAHs) selected for its ubiquity, persistence and high potential of environmental hazard. The EOX analysis give a picture of the total load of organo halogen compounds in the estuarine area and the VOC and ph values obtained, allow the characterization of sediments in two areas in function of the closeness to the urban and industrial activities

  1. Evaluating Bay Area Methane Emission Inventory

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Marc [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jeong, Seongeun [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2016-03-01

    As a regulatory agency, evaluating and improving estimates of methane (CH4) emissions from the San Francisco Bay Area is an area of interest to the Bay Area Air Quality Management District (BAAQMD). Currently, regional, state, and federal agencies generally estimate methane emissions using bottom-up inventory methods that rely on a combination of activity data, emission factors, biogeochemical models and other information. Recent atmospheric top-down measurement estimates of methane emissions for the US as a whole (e.g., Miller et al., 2013) and in California (e.g., Jeong et al., 2013; Peischl et al., 2013) have shown inventories underestimate total methane emissions by ~ 50% in many areas of California, including the SF Bay Area (Fairley and Fischer, 2015). The goal of this research is to provide information to help improve methane emission estimates for the San Francisco Bay Area. The research effort builds upon our previous work that produced methane emission maps for each of the major source sectors as part of the California Greenhouse Gas Emissions Measurement (CALGEM) project (http://calgem.lbl.gov/prior_emission.html; Jeong et al., 2012; Jeong et al., 2013; Jeong et al., 2014). Working with BAAQMD, we evaluate the existing inventory in light of recently published literature and revise the CALGEM CH4 emission maps to provide better specificity for BAAQMD. We also suggest further research that will improve emission estimates. To accomplish the goals, we reviewed the current BAAQMD inventory, and compared its method with those from the state inventory from the California Air Resources Board (CARB), the CALGEM inventory, and recent published literature. We also updated activity data (e.g., livestock statistics) to reflect recent changes and to better represent spatial information. Then, we produced spatially explicit CH4 emission estimates on the 1-km modeling grid used by BAAQMD. We present the detailed activity data, methods and derived emission maps by sector

  2. Daya Bay Nuclear Power Station equipment reliability management system innovation

    International Nuclear Information System (INIS)

    Gao Ligang; Wang Zongjun

    2006-01-01

    Daya Bay Nuclear Power Station has achieved good performance since its commercial operation in 1994. The equipment reliability management system that features Daya Bay characteristics has been established through constant technology introduction, digestion and innovation. It is also based on the success of operational system, equipment maintenance system and technical support system. The system lays a solid foundation for the long-term safe operation of power station. This article emphasizes on the innovation part of equipment reliability management system in Daya Bay. (authors)

  3. Defining a data management strategy for USGS Chesapeake Bay studies

    Science.gov (United States)

    Ladino, Cassandra

    2013-01-01

    The mission of U.S. Geological Survey’s (USGS) Chesapeake Bay studies is to provide integrated science for improved understanding and management of the Chesapeake Bay ecosystem. Collective USGS efforts in the Chesapeake Bay watershed began in the 1980s, and by the mid-1990s the USGS adopted the watershed as one of its national place-based study areas. Great focus and effort by the USGS have been directed toward Chesapeake Bay studies for almost three decades. The USGS plays a key role in using “ecosystem-based adaptive management, which will provide science to improve the efficiency and accountability of Chesapeake Bay Program activities” (Phillips, 2011). Each year USGS Chesapeake Bay studies produce published research, monitoring data, and models addressing aspects of bay restoration such as, but not limited to, fish health, water quality, land-cover change, and habitat loss. The USGS is responsible for collaborating and sharing this information with other Federal agencies and partners as described under the President’s Executive Order 13508—Strategy for Protecting and Restoring the Chesapeake Bay Watershed signed by President Obama in 2009. Historically, the USGS Chesapeake Bay studies have relied on national USGS databases to store only major nationally available sources of data such as streamflow and water-quality data collected through local monitoring programs and projects, leaving a multitude of other important project data out of the data management process. This practice has led to inefficient methods of finding Chesapeake Bay studies data and underutilization of data resources. Data management by definition is “the business functions that develop and execute plans, policies, practices and projects that acquire, control, protect, deliver and enhance the value of data and information.” (Mosley, 2008a). In other words, data management is a way to preserve, integrate, and share data to address the needs of the Chesapeake Bay studies to better

  4. The effect of loss functions on empirical Bayes reliability analysis

    Directory of Open Access Journals (Sweden)

    Vincent A. R. Camara

    1999-01-01

    Full Text Available The aim of the present study is to investigate the sensitivity of empirical Bayes estimates of the reliability function with respect to changing of the loss function. In addition to applying some of the basic analytical results on empirical Bayes reliability obtained with the use of the “popular” squared error loss function, we shall derive some expressions corresponding to empirical Bayes reliability estimates obtained with the Higgins–Tsokos, the Harris and our proposed logarithmic loss functions. The concept of efficiency, along with the notion of integrated mean square error, will be used as a criterion to numerically compare our results.

  5. Environmental and Sanitary Conditions of Guanabara Bay, Rio de Janeiro

    OpenAIRE

    Fistarol, Giovana O.; Coutinho, Felipe H.; Moreira, Ana Paula B.; Venas, Tain?; C?novas, Alba; de Paula, S?rgio E. M.; Coutinho, Ricardo; de Moura, Rodrigo L.; Valentin, Jean Louis; Tenenbaum, Denise R.; Paranhos, Rodolfo; do Valle, Rog?rio de A. B.; Vicente, Ana Carolina P.; Amado Filho, Gilberto M.; Pereira, Renato Crespo

    2015-01-01

    Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km2. In its surroundings live circa 16 million inhabitants, out of which 6 million live in Rio de Janeiro city, one of the largest cities of the country, and the host of the 2016 Olympic Games. Anthropogenic interference in Guanabara Bay area started early in the XVI century, but environmental impacts escalated from 1930, when this region underwent an industrialization process. Herein we present an overview of...

  6. Environmental and sanitary conditions of Guanabara Bay, Rio de Janeiro

    OpenAIRE

    Giovana De Oliveira Fistarol; Felipe H. Coutinho; Ana Paula Barbosa Moreira; Tainá eVenas; Alba eCanovas; Sergio E M de Paula Jr; Ricardo eCoutinho; Rodrigo L de Moura; Jean L Valentin; Denise R Tenenbaum; Rodolfo eParanhos; Rogerio eValle; Rogerio eValle; Cristiane eTHOMPSON; Paulo eSalomon

    2015-01-01

    Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km2. In its surroundings live circa 16 million inhabitants, out of which 6 million live in Rio de Janeiro city, one of the largest cities of the country, and the host of the 2016 Olympic Games. Anthropogenic interference in Guanabara Bay area started early in the XVI century, but environmental impacts escalated from 1930, when this region underwent an industrialization process. Herein we present an overview of...

  7. Improvement of FLOWER code and its application in Daya Bay

    International Nuclear Information System (INIS)

    Zhang Shaodong; Zhang Yongxing

    1995-01-01

    FLOWER, a computer code recommended by USNRC for assessing the environmental impact in tidal regions, was adapted and improved so as to be suitable to deal with the influence of drift stream along seashore to the dilution of contaminants and heat in the bay mouth. And the code outputs were presented with more mid-results such as average concentrations and temperature values for all tides considered. Finally, the modified code is applied to the dispersion calculation of heat and liquid effluents from Daya Bay Nuclear Power Plant, and the impacts from routine operation of the plant on Daya Bay sea waters were given

  8. The Neoglacial landscape and human history of Glacier Bay, Glacier Bay National Park and Preserve, southeast Alaska, USA

    Science.gov (United States)

    Connor, C.; Streveler, G.; Post, A.; Monteith, D.; Howell, W.

    2009-01-01

    The Neoglacial landscape of the Huna Tlingit homeland in Glacier Bay is recreated through new interpretations of the lower Bay's fjordal geomorphology, late Quaternary geology and its ethnographic landscape. Geological interpretation is enhanced by 38 radiocarbon dates compiled from published and unpublished sources, as well as 15 newly dated samples. Neoglacial changes in ice positions, outwash and lake extents are reconstructed for c. 5500?????"200 cal. yr ago, and portrayed as a set of three landscapes at 1600?????"1000, 500?????"300 and 300?????"200 cal. yr ago. This history reveals episodic ice advance towards the Bay mouth, transforming it from a fjordal seascape into a terrestrial environment dominated by glacier outwash sediments and ice-marginal lake features. This extensive outwash plain was building in lower Glacier Bay by at least 1600 cal. yr ago, and had filled the lower bay by 500 cal. yr ago. The geologic landscape evokes the human-described landscape found in the ethnographic literature. Neoglacial climate and landscape dynamism created difficult but endurable environmental conditions for the Huna Tlingit people living there. Choosing to cope with environmental hardship was perhaps preferable to the more severely deteriorating conditions outside of the Bay as well as conflicts with competing groups. The central portion of the outwash plain persisted until it was overridden by ice moving into Icy Strait between AD 1724?????"1794. This final ice advance was very abrupt after a prolonged still-stand, evicting the Huna Tlingit from their Glacier Bay homeland. ?? 2009 SAGE Publications.

  9. NUMERICAL MODELS AS TOOLS TO UNDERSTAND THE DYNAMICS IN BAYS: CASE OF STUDY CHETUMAL BAY, QUINTANA ROO

    Directory of Open Access Journals (Sweden)

    David Avalos-Cueva

    2017-07-01

    Full Text Available In this study performed the simulation of currents generated by the wind on the Bay of Chetumal, Quintana Roo through the use of a stationary shallow-water model. A homogeneous climatic wind was used for the entire Bay, with a velocity of 3m·s-1 , and directions North, South, Northeast, Northwest, East, Southeast, Southwest and West. The results showed a rather complex dynamics in Chetumal Bay, in which important turns were observed in deep areas, with speeds reaching up to 13 cm·s-1 .

  10. Shallow-water Benthic Habitats 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...

  11. Delaware Bay, Delaware Sediment Distribution 2003 to 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The area of coverage consists of 38 square miles of benthic habitat mapped from 2003 to 2004 along the middle to lower Delaware Bay Coast. The bottom sediment map...

  12. Bristol Bay, Alaska Subarea ESI: NESTS (Nest Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for nesting seabirds (alcids, pelagic birds), gulls, terns, diving birds, and raptors in the Bristol Bay...

  13. Neah Bay, Washington Tsunami Forecast Grids for MOST Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Neah Bay, Washington Forecast Model Grids provides bathymetric data strictly for tsunami inundation modeling with the Method of Splitting Tsunami (MOST) model....

  14. Bristol Bay, Alaska Subarea ESI: MGT (Management Area Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive human-use data for Critical Habitats, Wildlife Refuges, National Park lands, and other management areas in the Bristol Bay Subarea....

  15. Data supporting study of Ecosystem Metabolism in Pensacola Bay estuary

    Data.gov (United States)

    U.S. Environmental Protection Agency — These files house the data collected during 2013 in lower Pensacola Bay. The data were used to estimate aquatic primary production and respiration. This dataset is...

  16. Theories of transporting processes of Cu in Jiaozhou Bay

    Science.gov (United States)

    Yang, Dongfang; Su, Chunhua; Zhu, Sixi; Wu, Yunjie; Zhou, Wei

    2018-02-01

    Many marine bays have been polluted along with the rapid development of industry and population size, and understanding the transporting progresses of pollutants is essential to pollution control. In order to better understanding the transporting progresses of pollutants in marine, this paper carried on a comprehensive research of the theories of transporting processes of Cu in Jiaozhou Bay. Results showed that the transporting processes of Cu in this bay could be summarized into seven key theories including homogeneous theory, environmental dynamic theory, horizontal loss theory, source to waters transporting theory, sedimentation transporting theory, migration trend theory and vertical transporting theory, respectively. These theories helpful to better understand the migration progress of pollutants in marine bay.

  17. Searching for ?_1_3 at Daya Bay

    International Nuclear Information System (INIS)

    Giedt, Joel; Napolitano, James

    2015-01-01

    An experiment has been carried out by the Daya Bay Collaboration to measure the neutrino mixing angle θ_1_3. In addition, the grant has supported research into lattice field theory beyond the standard model.

  18. San Francisco Bay Multi-beam Bathymetry: Area A

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These multi-beam bathymetric data were collected over shallow subtidal areas in the San Francisco Bay estuary system. Bathymetric and acoustic backscatter data were...

  19. Bristol Bay, Alaska Subarea ESI: BIRDS (Bird Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for shorebirds, waterfowl, raptors, diving birds, and seabirds in the Bristol Bay Subarea. The Subarea...

  20. San Francisco Bay Interferometric Side Scan Imagery: Area A

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Backscatter imagery data were collected over shallow subtidal areas in the San Francisco Bay estuary system. Bathymetric and acoustic backscatter data were collected...

  1. Southern Monterey Bay Littoral Cell CRSMP Sensitive Habitat 2008

    Data.gov (United States)

    California Natural Resource Agency — One of the most important functions of the southern Monterey Bay coastal system is its role as a habitat for a unique flora and fauna. The beaches are habitat for...

  2. Assembly and Installation of the Daya Bay Antineutrino Detectors

    International Nuclear Information System (INIS)

    Band, H R; Heeger, K M; Hinrichs, P; Brown, R L; Gill, R; Carr, R; Dwyer, D A; Chen, X C; Chu, M C; Chen, X H; Heng, Y K; Cherwinka, J J; Greenler, L S; Draeger, E; Edwards, W R; Hoff, M; Goett, J; Gu, W Q; Ho, T H; He, W S

    2013-01-01

    The Daya Bay reactor antineutrino experiment is designed to make a precision measurement of the neutrino mixing angle θ 13 , and recently made the definitive discovery of its non-zero value. It utilizes a set of eight, functionally identical antineutrino detectors to measure the reactor flux and spectrum at baselines of ∼ 300–2000 m from the Daya Bay and Ling Ao Nuclear Power Plants. The Daya Bay antineutrino detectors were built in an above-ground facility and deployed side-by-side at three underground experimental sites near and far from the nuclear reactors. This configuration allows the experiment to make a precision measurement of reactor antineutrino disappearance over km-long baselines and reduces relative systematic uncertainties between detectors and nuclear reactors. This paper describes the assembly and installation of the Daya Bay antineutrino detectors

  3. Southern Monterey Bay Littoral Cell CRSMP Proposed Receiver Site 2008

    Data.gov (United States)

    California Natural Resource Agency — Given the location of the critical areas of erosion and the need to avoid adverse impacts to local sensitive habitat, the Southern Monterey Bay Coastal RSM Plan...

  4. Eureka Littoral Cell CRSMP Humboldt Bay Shoreline Types 2011

    Data.gov (United States)

    California Natural Resource Agency — In 2011 Aldaron Laird walked and kayaked the entire shoreline of Humboldt Bay mapping the shoreline conditions onto 11x17 laminated fieldmaps at a scale of 1' = 200'...

  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.

    Hydrographic and XBT data archived in the Indian Oceanographic Data Centre (IODC) are used to understand the process of temperature inversions occurring in the Bay of Bengal. The following aspects of the inversions are addressed: i) annual...

  6. Circulation and geostrophic transport in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, D.P.; Murty, V.S.N.

    Utilising the hydrographic data collected during the early northeast monsoon of 1983 and southwest monsoon of 1984, the circulation of waters of the Bay of Bengal and the associated volume transport have been studied in the upper 1000 m...

  7. National Status and Trends: Bioeffects Program - Kachemak Bay Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study was based on the sediment quality triad (SQT) approach. A stratified probabilistic sampling design was utilized to characterize the Kachemak Bay system in...

  8. Creating Safe Growth Strategies for the San Francisco Bay Area

    Science.gov (United States)

    Report from a technical assistance project with the Association of Bay Area Governments to develop strategies to ensure that growth in the region is resilient to hazards such as earthquakes and sea level rise, but also affordable and transit accessible.

  9. Macrofouling community structure in Kanayama Bay, Kii Peninsula (Japan)

    Digital Repository Service at National Institute of Oceanography (India)

    Raveendran, T.V.; Harada, E.

    An investigation on the macrofouling community in Kanayama Bay, Kill Peninsula, Japan was undertaken from June 1994 to May 1995 by exposing fiber reinforced plastic (FRP) panels at subsurface and bottom (2.2 m) depths. The composition and abundance...

  10. DDT residues in sediments from the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarkar, A.; SenGupta, R.

    in the sediments from the Bay of Bengal. Peterson grab and hydrographic winch was used to collect the sediment samples. Each sample was extracted and cleaned. Residues were detected by electron capture gas chromatography. A range variation in the concentration...

  11. Diffusion characteristics of the Kakinada Bay for effluent assessment

    Digital Repository Service at National Institute of Oceanography (India)

    Unnikrishnan, A.S.; Asthana, V.

    The present study reports the determination of diffusion characteristics of the Kakinada Bay to choose a suitable marine outfall location for industrial discharge of effluents from a proposed fertilizer plant. The study consisted of dye diffusion...

  12. Primary production in the Bay of Bengal during August 1977

    Digital Repository Service at National Institute of Oceanography (India)

    Devassy, V.P.; Bhattathiri, P.M.A.; Radhakrishna, K.

    Primary production, chlorophyll @ia@@, phaeophytin, phytoplankton and particulate organic carbon (POC) were studied at 14 stations in the Bay of Bengal during August 1977. Column primary production, chlorophyll @ia@@, and phaeopigments varied from 0...

  13. Tampa Bay Topographic/Bathymetric Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In this joint demonstration project for the Tampa Bay region, NOAA's National Ocean Service (NOS) and the U.S. Geological Survey (USGS) have merged NOAA bathymetric...

  14. Magnitude and Distribution of Flows into Northeastern Florida Bay

    Science.gov (United States)

    Patino, Eduardo; Hittle, Clinton D.

    2000-01-01

    Changes in water-management practices have been made to accommodate a large and rapidly growing urban population along the Atlantic Coast and to meet the demand for intensive agricultural activities. These changes have resulted in a highly managed hydrologic system consisting of numerous canals, levees, control structures, and pumping stations that have altered the hydrology of the Everglades and Florida Bay ecosystems. Over the past decade, Florida Bay has experienced sea-grass die-off and algal blooms, which are indicators of ecological change attributed primarily to the increase in salinity and nutrient content of bay waters. Because plans are to restore sheetflow in the Everglades wetlands to its natural state, water managers anticipate a change in the magnitude and timing of freshwater exiting the mainland through the creeks that cut through the embankment or as sheetflow into Florida Bay.

  15. National Status and Trends: Bioeffects Program - San Francisco Bay Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study was based on the sediment quality triad (SQT) approach. A stratified probabilistic sampling design was utilized to characterize the San Francisco Bay...

  16. A LEOPARD SEAL FROM HOUT BAY, SOUTH AFRICA Division of ...

    African Journals Online (AJOL)

    On 14 October 1969 a leopard seal Hydrurga leptonyx came ashore alive at Hout Bay, Cape. Province .... 5 mm in diameter: on histological examination these proved to be small nematodes Para- filaroides sp. ... Seals, sea lions and walruses.

  17. AFSC/ABL: Auke Bay Climatology 1959-2013

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data set includes available climatological and related physical environmental records for Auke Bay, Auke Creek and Auke Lake beginning in 1959. Daily high and low...

  18. Southern Monterey Bay Littoral Cell CRSMP Proposed Receiver Site 2008

    Data.gov (United States)

    California Department of Resources — Given the location of the critical areas of erosion and the need to avoid adverse impacts to local sensitive habitat, the Southern Monterey Bay Coastal RSM Plan...

  19. Field guide to fishes of the chesapeake bay

    CERN Document Server

    Murdy, Edward O.

    2013-01-01

    The only comprehensive field guide to the Chesapeake’s fishes, this book is an indispensable resource for both anglers and students of the Bay. Vivid illustrations by Val Kells complement the expertise of researchers Edward O. Murdy and John A. Musick. They describe fishes that inhabit waters ranging from low-salinity estuaries to the point where the Bay meets the Atlantic Ocean. Key features of this field guide include• full-color illustrations of more than 200 species• text that is presented adjacent to illustrations for easy reference• detailed descriptions of physical characteristics, range, occurrence in the Bay, reproduction, diet, and statistics from fisheries research• spot illustrations that highlight critical features of certain fish• illustrations of juveniles when they look different from adults• appendices that include identification keys Formatted as a compact field guide for students, scientists, researchers, and fishermen, Field Guide to Fishes of the Chesapeake Bay should be a ...

  20. Southern Monterey Bay Littoral Cell CRSMP Sensitive Habitat 2008

    Data.gov (United States)

    California Department of Resources — One of the most important functions of the southern Monterey Bay coastal system is its role as a habitat for a unique flora and fauna. The beaches are habitat for...

  1. Seasonal dimethylsulfoniopropionate (DMSP) variability in Dona Paula Bay

    Digital Repository Service at National Institute of Oceanography (India)

    Kumar, S.S.; Chinchkar, U.; Nair, S.; LokaBharathi, P.A.; Chandramohan, D.

    as producers of DMSP in Dona Paula bay. Dinoflagellates also contributed during the non-monsoon seasons. Another factor involved in the variability of DMSPt was DMSP utilizing bacteria, which ranged from 1 to 10% of the total heterotrophic count...

  2. The American Satellite Company (ASC) satellite deployed from payload bay

    Science.gov (United States)

    1985-01-01

    The American Satellite Company (ASC) communications satellite is deployed from the payload bay of the Shuttle Discovery. A portion of the cloudy surface of the earth can be seen to the left of the frame.

  3. Influence of orographically steered winds on Mutsu Bay surface currents

    Science.gov (United States)

    Yamaguchi, Satoshi; Kawamura, Hiroshi

    2005-09-01

    Effects of spatially dependent sea surface wind field on currents in Mutsu Bay, which is located at the northern end of Japanese Honshu Island, are investigated using winds derived from synthetic aperture radar (SAR) images and a numerical model. A characteristic wind pattern over the bay was evidenced from analysis of 118 SAR images and coincided with in situ observations. Wind is topographically steered with easterly winds entering the bay through the terrestrial gap and stronger wind blowing over the central water toward its mouth. Nearshore winds are weaker due to terrestrial blockages. Using the Princeton Ocean Model, we investigated currents forced by the observed spatially dependent wind field. The predicted current pattern agrees well with available observations. For a uniform wind field of equal magnitude and average direction, the circulation pattern departs from observations demonstrating that vorticity input due to spatially dependent wind stress is essential in generation of the wind-driven current in Mutsu Bay.

  4. Massachusetts Bay - Internal wave packets digitized from SAR imagery

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This feature class contains internal wave packets digitized from SAR imagery at 1:350,000 scale in Massachusetts Bay. Internal waves are nonsinusoidal waves that...

  5. Searching for θ13 at Daya Bay

    Energy Technology Data Exchange (ETDEWEB)

    Giedt, Joel [Rensselaer Polytechnic Inst., Troy, NY (United States); Napolitano, James [Temple Univ., Philadelphia, PA (United States)

    2015-06-08

    An experiment has been carried out by the Daya Bay Collaboration to measure the neutrino mixing angle θ13. In addition, the grant has supported research into lattice field theory beyond the standard model.

  6. Physical oceanography of the Bay of Bengal and Andaman Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Varkey, M.J.; Murty, V.S.N.; Suryanarayana, A.

    Physical oceanography of the Bay of Bengal and Andaman Sea is reviewed for the first time. All available information for over 50 years is consolidated in this review. To begin with, information on peripheral or related aspects of climate...

  7. San Francisco Bay, California 1 arc-second DEM

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The 1-second San Francisco Bay, California Elevation Grid provides bathymetric data in ASCII raster format of 1-second resolution in geographic coordinates. This...

  8. Bristol Bay, Alaska Subarea ESI: HABITATS (Habitats Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for submerged aquatic vegetation (SAV) in the Bristol Bay Subarea. The Subarea includes marine and coastal...

  9. Salt balance and mixing in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Varkey, M.J.

    Basic fields of temperature salinity, density and currents in the Bay of Bengal are investigated using data archieved at the National Oceanographic Data Centre (NODC) Washington, D.C. and the Indian National Oceanographic Data Centre (INODC...

  10. Canonical sound speed profile for the central Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Murty, T.V.R.; PrasannaKumar, S.; Somayajulu, Y.K.; Sastry, J.S.; De Figueiredo, R.J.P.

    Following Munk's canonical theory, an algorithm has been presented for computing sound channel parameters in the western and southern Bay of Bengal. The estimated canonical sound speed profile using these parameters has been compared with computed...

  11. Long-term morphologic evolution of the Hangzhou Bay, China

    Science.gov (United States)

    Wen, W.; Zhijun, D.; Hualiang, X.

    2013-12-01

    Estuaries are the most productive ecosystems of coastal zones in the world, which are significant to mankind as places of navigation, recreation and commerce as well as extensive and diverse habitats for wildlife. However, most estuary environments in the world had occurred greatly changes in recent decades. These estuaries have suffered from impacts of forcing factors including wave climate, mean sea level change and storm surge, especial to the intensive human activities such as training wall construction, channel dredging, sand mining and dam constructions. Thus, there have been increasing concerns about estuary environment changes under effects of different factors. Riverine loads into the Changjiang Estuary have declined dramatically with the construction of Three Gorges Dam (TGD) in 2003. The morphological evolution of the Hangzhou bay that located the southern proximity of the Yangtze estuary starts to attract increasing attentions due to most material of the Hangzhou bay received from Yangtze estuary. In this paper, historical bathymetric charts were digitized and analyzed within a GIS to provide quantitative estimate of changes in volumes in different regions below 0 m elevation. The results show that Hangzhou bay has experienced a major loss in estuarine volume of about 15% with annual mean sediment deposition rate of 80 million m3/a during the last 75 years. However, there is a large-scale spatial adjustment in Hangzhou bay: Bathymetric changes of the Hangzhou bay can be rapidly shifted within the range of 8-10 classes. Volume of the Jinshanzui upstream of the Hangzhou bay has obviously decreased in the last 75 years, especially during 2003-2008. However, Volume of the southern Hangzhou bay has experienced slowly decrease with minor deposition. The northern Hangzhou bay had largely volume changes with rapidly decrease during 1931-1981, and drastically increase since 2003. Further analysis of the bathymetric data relating to possible factors indicates

  12. PENERAPAN NAIVE BAYES PADA INTRUSION DETECTION SYSTEM DENGAN DISKRITISASI VARIABEL

    Directory of Open Access Journals (Sweden)

    I Nyoman Trisna Wirawan

    2015-07-01

    Pada penelitian ini akan dibahas mengenai penerapan naive bayes classifier dengan menggunakan pemilihan atribut berdasarkan pada korelasi serta preprocessing data dengan diskritisasi dengan menggunakan metode mean/standar deviasi untuk atribut kontinu dengan menggunakan 3-interval dan 5-interval. Hasil percobaan menunjukan bahwa penerapan naive bayes pada klasifikasi data yang telah melewati proses diskritisasi mampu memberikan akurasi hingga 89% dengan running time rata-rata adalah 31 detik.

  13. 76 FR 23189 - Safety Zone; Pensacola Bay; Pensacola, FL

    Science.gov (United States)

    2011-04-26

    ...-AA00 Safety Zone; Pensacola Bay; Pensacola, FL AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone for a portion of Pensacola Bay including...[deg]17'20.31'' W, 30[deg]20'41.51'' N 087[deg]15'01.15'' W, and 30[deg]20'11.76'' N 087[deg]15'01.18...

  14. Environmental and Sanitary Conditions of Guanabara Bay, Rio de Janeiro

    Science.gov (United States)

    Fistarol, Giovana O.; Coutinho, Felipe H.; Moreira, Ana Paula B.; Venas, Tainá; Cánovas, Alba; de Paula, Sérgio E. M.; Coutinho, Ricardo; de Moura, Rodrigo L.; Valentin, Jean Louis; Tenenbaum, Denise R.; Paranhos, Rodolfo; do Valle, Rogério de A. B.; Vicente, Ana Carolina P.; Amado Filho, Gilberto M.; Pereira, Renato Crespo; Kruger, Ricardo; Rezende, Carlos E.; Thompson, Cristiane C.; Salomon, Paulo S.; Thompson, Fabiano L.

    2015-01-01

    Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km2. In its surroundings live circa 16 million inhabitants, out of which 6 million live in Rio de Janeiro city, one of the largest cities of the country, and the host of the 2016 Olympic Games. Anthropogenic interference in Guanabara Bay area started early in the XVI century, but environmental impacts escalated from 1930, when this region underwent an industrialization process. Herein we present an overview of the current environmental and sanitary conditions of Guanabara Bay, a consequence of all these decades of impacts. We will focus on microbial communities, how they may affect higher trophic levels of the aquatic community and also human health. The anthropogenic impacts in the bay are flagged by heavy eutrophication and by the emergence of pathogenic microorganisms that are either carried by domestic and/or hospital waste (e.g., virus, KPC-producing bacteria, and fecal coliforms), or that proliferate in such conditions (e.g., vibrios). Antibiotic resistance genes are commonly found in metagenomes of Guanabara Bay planktonic microorganisms. Furthermore, eutrophication results in recurrent algal blooms, with signs of a shift toward flagellated, mixotrophic groups, including several potentially harmful species. A recent large-scale fish kill episode, and a long trend decrease in fish stocks also reflects the bay’s degraded water quality. Although pollution of Guanabara Bay is not a recent problem, the hosting of the 2016 Olympic Games propelled the government to launch a series of plans to restore the bay’s water quality. If all plans are fully implemented, the restoration of Guanabara Bay and its shores may be one of the best legacies of the Olympic Games in Rio de Janeiro. PMID:26635734

  15. Severe Weather Guide - Mediterranean Ports. 4. Augusta Bay

    Science.gov (United States)

    1988-03-01

    the year. The track o-f strong extratropical storms has moved northward and poses little tiireat to Augusta Bay. Sea breezes are daily occurrences...as temperatures, begin to moderate. Extratropi cal systems begin to transit Europe as the storm track moves southward in advance of the winter...SUB-GROUP 18. SUBJECT TERMS {Continue on reverse if necessary and identify by block number) Storm haven Mediterranean meteorology Augusta Bay

  16. Observation on Heavy Metals in Sediment of Jakarta Bay Waters

    Directory of Open Access Journals (Sweden)

    Abdul Rozak

    2007-04-01

    Full Text Available Observation on heavy metals in Jakarta Bay, from June and September 2003. Heavy metals Pb in sediment at the West have been conductet of Jakarta Bay Waters varied between Pb = 8,49-31,22 ppm, Cd = <0,001-0,47 ppm, Cu = 13,81-193,75 ppm, Zn = 82,18-533,59 ppm and Ni = 0,99-35,38 ppm,while those at the Center of Jakarta Bay, varied between Pb = 2,21-69,22 ppm, Cd = <0,001-0,28 ppm, Cu = 3,36-50,65 ppm, Zn = 71,13-230,54 ppm and Ni = 0,42-15,58 ppm and at the East of Jakarta Bay, Pb content varied between 0,25-77,42 ppm, Cd = <0,001-0,42 ppm, Cu = 0,79-44,94 ppm, Zn = 93,21-289,00 ppm and Ni = 0,42-128,47 ppm. Hevy metals content in sediment the West of Jakarta Bay was high of equivalent the Center and East of Jakarta Bay. At than those composition sediment at the west was black, that indicated high heavy metals content.

  17. 76 FR 2409 - Proclaiming Certain Lands, Golf Course Acquisition, as an Addition to the Bay Mills Indian...

    Science.gov (United States)

    2011-01-13

    ... Acquisition, as an Addition to the Bay Mills Indian Reservation for the Bay Mills Indian Community of Michigan..., more or less, to be added to the Bay Mills Indian Reservation for the Bay Mills Indian Community of... the land described below. The land was proclaimed to be an addition to the Bay Mills Indian...

  18. 77 FR 54607 - Proclaiming Certain Lands, Sugar Parcel Lands, as an Addition to the Bay Mills Indian Reservation...

    Science.gov (United States)

    2012-09-05

    ..., as an Addition to the Bay Mills Indian Reservation for the Bay Mills Indian Community of Michigan... acres, more or less, to be added to the Bay Mills Indian Reservation for the Bay Mills Indian Community... the land described below. The land was proclaimed to be an addition to the Bay Mills Indian...

  19. 76 FR 2409 - Proclaiming Certain Lands, Lots 15 and 16 Acquisition, as an Addition to the Bay Mills Indian...

    Science.gov (United States)

    2011-01-13

    ... Acquisition, as an Addition to the Bay Mills Indian Reservation for the Bay Mills Indian Community of Michigan..., more or less, to be added to the Bay Mills Indian Reservation for the Bay Mills Indian Community of... the land described below. The land was proclaimed to be an addition to the Bay Mills Indian...

  20. 77 FR 54607 - Proclaiming Certain Lands, Dafter Parcel, as an Addition to the Bay Mills Indian Reservation for...

    Science.gov (United States)

    2012-09-05

    ... an Addition to the Bay Mills Indian Reservation for the Bay Mills Indian Community of Michigan AGENCY..., more or less, to be added to the Bay Mills Indian Reservation for the Bay Mills Indian Community of... the land described below. The land was proclaimed to be an addition to the Bay Mills Indian...

  1. 76 FR 52011 - Proclaiming Certain Lands, Forest Service Lands, as an Addition to the Bay Mills Indian...

    Science.gov (United States)

    2011-08-19

    ... Lands, as an Addition to the Bay Mills Indian Reservation for the Bay Mills Indian Community of Michigan... acres, more or less, to be added to the Bay Mills Indian Reservation for the Bay Mills Indian Community... the land described below. The land was proclaimed to be an addition to the Bay Mills Indian...

  2. 76 FR 2409 - Proclaiming Certain Lands, Lot 32 Acquisition, as an Addition to the Bay Mills Indian Reservation...

    Science.gov (United States)

    2011-01-13

    ..., as an Addition to the Bay Mills Indian Reservation for the Bay Mills Indian Community of Michigan..., more or less, to be added to the Bay Mills Indian Reservation for the Bay Mills Indian Community of... Mills Indian Reservation and part of the Bay Mills Indian Community of Michigan for the exclusive use of...

  3. San Francisco Bay Area Baseline Trash Loading Summary Results, San Francisco Bay Area CA, 2012, US EPA Region 9

    Data.gov (United States)

    U.S. Environmental Protection Agency — The San Francisco Bay Area stormwater permit sets trash control guidelines for discharges through the storm drain system. The permit covers Alameda, Contra Costa,...

  4. Recipient Capacity of Tvaeren, a Baltic Bay

    International Nuclear Information System (INIS)

    Agnedal, P.O.; Bergstroem, S.O.W.

    1966-07-01

    The research station at Studsvik is situated on the Baltic coast and includes several reactors and laboratories, a waste disposal plant serving both the station and waste producers outside Studsvik. A storage plant for irradiated fuel from power reactors has also been built. A total of 850 people are employed. The waste disposal plant was designed for a personnel of 900 using foreign information to correlate waste amounts to personnel. After a delay production has increased at a rate very close to the one expected. The composition of the waste is varied and difficult to predict. Minor amounts of fission products, active corrosion products, and fissile materials have been detected. Most of the waste activity is released to a strait leading into the Bay. Large volumes of water with very low specific activity are released immediately off the coast. Hydrological and dispersion data for the bay are quoted from a paper presented at the symposium mentioned below. The Baltic has brackish water. Both the chemistry and the biology are quite different from those of marine or fresh water recipients. A short description is given of the fauna and flora and important food webs are discussed. The different ways in which man is exposed to radioactivity in waste releases are dependent upon biological accumulation in living organisms and adsorption to dead materials. Fish consumption is the type of exposure which is likely to be the most critical, though it is possible that the exposure from sunbathing and fishing-gear handling could reach similar significance if conservative calculations are used. Accumulation factors from water to fish are given for iron, cobalt,and zinc . Permissible releases have been calculated using relevant accumulation factors. Fission products and corrosion products seem to be of similar significance with regard to possible human exposure. Permission to release liquid waste is granted by water courts in Sweden and operations inspected by special authorities

  5. Environmental geology of Harrison Bay, northern Alaska

    Science.gov (United States)

    Craig, J.D.; Thrasher, G.P.

    1982-01-01

    The surficial and shallow subsurface geology of Harrison Bay on the Beaufort Sea coast was mapped as part of the U.S. Geological Survey's prelease evaluation for Outer Continental Shelf (OCS) Oil and Gas Lease Sale 71. During the 1980 summer season, approximately 1600 km of multisensored, high-resolution geophysical profile data were collected along a rectangular grid with 4.8 km line spacing. Interpretation of these data is presented on five maps showing bathymetry, sea-floor microrelief, ice-gouge characteristics, Holocene sediment thickness, and geologic structure to depths of approximately 1000 m. On a broad scale, the seafloor is shallow and almost flat, although microrelief features produced by sediment transport and ice-gouge processes typically vary up to several meters in amplitude. Microrelief bedforms related to hydraulic processes are predominant in water depths less than 12 m. Microrelief caused by ice gouging generally increases with water depth, reaching a maximum of 2 m or more in water depths beyond the 20 m isobath. This intensely gouged area lies beneath the shear zone between the seasonal landfast ice and the mobile polar ice pack. The thickness of recent (Holocene) sediment increases offshore, from 2 m near the Colville River delta to 30 m or more on the outer shelf. The thin Holocene layer is underlain by a complex horizon interpreted to be the upper surface of a Pleistocene deposit similar in composition to the present Arctic Coastal Plain. The base of the inferred Pleistocene section is interpreted to be a low-angle unconformity 100 m below sea level. Beneath this Tertiary-Quaternary unconformity, strata are interpreted to be alluvial fan-delta plain deposits corresponding to the Colville Group and younger formations of Late Cretaceous to Tertiary age. Numerous high-angle faults downthrown to the north trend across the survey area. With few exceptions, these faults terminate at or below the 100 m unconformity, suggesting that most tectonism

  6. Recipient Capacity of Tvaeren, a Baltic Bay

    Energy Technology Data Exchange (ETDEWEB)

    Agnedal, P O; Bergstroem, S O.W.

    1966-07-15

    The research station at Studsvik is situated on the Baltic coast and includes several reactors and laboratories, a waste disposal plant serving both the station and waste producers outside Studsvik. A storage plant for irradiated fuel from power reactors has also been built. A total of 850 people are employed. The waste disposal plant was designed for a personnel of 900 using foreign information to correlate waste amounts to personnel. After a delay production has increased at a rate very close to the one expected. The composition of the waste is varied and difficult to predict. Minor amounts of fission products, active corrosion products, and fissile materials have been detected. Most of the waste activity is released to a strait leading into the Bay. Large volumes of water with very low specific activity are released immediately off the coast. Hydrological and dispersion data for the bay are quoted from a paper presented at the symposium mentioned below. The Baltic has brackish water. Both the chemistry and the biology are quite different from those of marine or fresh water recipients. A short description is given of the fauna and flora and important food webs are discussed. The different ways in which man is exposed to radioactivity in waste releases are dependent upon biological accumulation in living organisms and adsorption to dead materials. Fish consumption is the type of exposure which is likely to be the most critical, though it is possible that the exposure from sunbathing and fishing-gear handling could reach similar significance if conservative calculations are used. Accumulation factors from water to fish are given for iron, cobalt,and zinc . Permissible releases have been calculated using relevant accumulation factors. Fission products and corrosion products seem to be of similar significance with regard to possible human exposure. Permission to release liquid waste is granted by water courts in Sweden and operations inspected by special authorities

  7. Short Term Sediment Exchange Between Marshes and Bays Using Beryllium-7 as a Tracer, Fourleague Bay, Louisiana.

    Science.gov (United States)

    Restreppo, G. A.; Bentley, S. J.; Xu, K.; Wang, J.

    2016-12-01

    Modern delta models focus on the availability and exchange of coarse sediment as one of the major factors of deltaic growth or decay. Fine-grained sediment exchange within a river's delta is relatively poorly understood, as is the impact that this exchange has on land building and land loss. To better understand the dynamics of fine grain sediment exchange between river mouth, adjacent bays, and marshland, sediment cores from Fourleague Bay, LA, were collected and analyzed for 7Be, a naturally occurring radioisotope that serves as a marker for recently deposited sediment. Time-series push cores were collected every two months at ten sites, five located across a longitudinal transect in the middle bay and five located along adjacent marshes, from May 2015 to May 2016. All sites fall within 11 to 28 km of the Atchafalaya Delta, along a gradient extending towards the open ocean. Cores were extruded in 2 cm intervals, dried, ground, and analyzed via gamma spectrometry for the presence of 7Be. Inventories of 7Be were then calculated and used to determine bimonthly sedimentation rates over the course twelve months. Sediment deposition on the bay floor and marsh surface were then compared to Atchafalaya River discharge, wind speed and direction, and wave action. Preliminary results indicate patterns of initial fluvial sediment transfer from river to bay floor, then bay floor to marsh surface, with decreasing fluvial influence towards the open ocean. Sediment transport from bay to marsh appears to be coupled with meteorological forcing that induces bay-floor sediment resuspension and the flooding of marsh surfaces. This indirect mechanism of fluvial sediment supply to wetland surfaces may extend the region of influence for sediment delivery from man-made river-sediment diversions.

  8. Status, trends, and changes in freshwater inflows to bay systems in the Corpus Christi Bay National Estuary Program study area

    Science.gov (United States)

    Asquith, W.H.; Mosier, J. G.; Bush, P.W.

    1997-01-01

    This report presents the results of a study to quantify current (1983–93) mean freshwater inflows to the six bay systems (open water and wetlands) in the Corpus Christi Bay National Estuary Program study area, to test for historical temporal trends in inflows, and to quantify historical and projected changes in inflows. The report also addresses the adequacy of existing data to estimate freshwater inflows.

  9. Study on origin and sedimentary environment of marine sediments from Kii Channel, Hiroshima Bay and Tosa Bay

    International Nuclear Information System (INIS)

    Suzuki, Misaki

    2008-01-01

    The trace amounts of elements in the sediments of sea bottom in Kii Channel, Hiroshima Bay and Tosa Bay were determined quantitatively by the neutron activation analysis. The following facts were illustrated particularly from the quantitative analysis of scandium, rare earths, thorium and uranium: 1) It was known from Ce/La ratio that the geological feature in the west part of Japan is reflected in Kii Channel, Hiroshima Bay and Tosa Bay; 2) The rare-earth element pattern and La/Lu ratio suggest the fact that Kii Channel, Hiroshima Bay and Tosa Bay are essentially composed of the materials of which origin is land; 3) From the fact that Ce/La ratio in these sites are slightly under 1.0, these sites are considered to be affected mainly by the materials of which origin is land; 4) The sedimentary environment in the marine bottom of the Japanese coasts has been found to be mostly under a reductive state. (M.H.)

  10. THE RESPONSE OF MONTEREY BAY TO THE 2010 CHILEAN EARTHQUAKE

    Directory of Open Access Journals (Sweden)

    Laurence C. Breaker

    2011-01-01

    Full Text Available The primary frequencies contained in the arrival sequence produced by the tsunami from the Chilean earthquake of 2010 in Monterey Bay were extracted to determine the seiche modes that were produced. Singular Spectrum Analysis (SSA and Ensemble Empirical Mode Decomposition (EEMD were employed to extract the primary frequencies of interest. The wave train from the Chilean tsunami lasted for at least four days due to multipath arrivals that may not have included reflections from outside the bay but most likely did include secondary undulations, and energy trapping in the form of edge waves, inside the bay. The SSA decomposition resolved oscillations with periods of 52-57, 34-35, 26-27, and 21-22 minutes, all frequencies that have been predicted and/or observed in previous studies. The EEMD decomposition detected oscillations with periods of 50-55 and 21-22 minutes. Periods in the range of 50-57 minutes varied due to measurement uncertainties but almost certainly correspond to the first longitudinal mode of oscillation for Monterey Bay, periods of 34-35 minutes correspond to the first transverse mode of oscillation that assumes a nodal line across the entrance of the bay, a period of 26- 27 minutes, although previously observed, may not represent a fundamental oscillation, and a period of 21-22 minutes has been predicted and observed previously. A period of ~37 minutes, close to the period of 34-35 minutes, was generated by the Great Alaskan Earthquake of 1964 in Monterey Bay and most likely represents the same mode of oscillation. The tsunamis associated with the Great Alaskan Earthquake and the Chilean Earthquake both entered Monterey Bay but initially arrived outside the bay from opposite directions. Unlike the Great Alaskan Earthquake, however, which excited only one resonant mode inside the bay, the Chilean Earthquake excited several modes suggesting that the asymmetric shape of the entrance to Monterey Bay was an important factor and that the

  11. DEVELOP Chesapeake Bay Watershed Hydrology - UAV Sensor Web

    Science.gov (United States)

    Holley, S. D.; Baruah, A.

    2008-12-01

    The Chesapeake Bay is the largest estuary in the United States, with a watershed extending through six states and the nation's capital. Urbanization and agriculture practices have led to an excess runoff of nutrients and sediment into the bay. Nutrients and sediment loading stimulate the growth of algal blooms associated with various problems including localized dissolved oxygen deficiencies, toxic algal blooms and death of marine life. The Chesapeake Bay Program, among other stakeholder organizations, contributes greatly to the restoration efforts of the Chesapeake Bay. These stakeholders contribute in many ways such as monitoring the water quality, leading clean-up projects, and actively restoring native habitats. The first stage of the DEVELOP Chesapeake Bay Coastal Management project, relating to water quality, contributed to the restoration efforts by introducing NASA satellite-based water quality data products to the stakeholders as a complement to their current monitoring methods. The second stage, to be initiated in the fall 2008 internship term, will focus on the impacts of land cover variability within the Chesapeake Bay Watershed. Multiple student led discussions with members of the Land Cover team at the Chesapeake Bay Program Office in the DEVELOP GSFC 2008 summer term uncovered the need for remote sensing data for hydrological mapping in the watershed. The Chesapeake Bay Program expressed in repeated discussions on Land Cover mapping that significant portions of upper river areas, streams, and the land directly interfacing those waters are not accurately depicted in the watershed model. Without such hydrological mapping correlated with land cover data the model will not be useful in depicting source areas of nutrient loading which has an ecological and economic impact in and around the Chesapeake Bay. The fall 2008 DEVELOP team will examine the use of UAV flown sensors in connection with in-situ and Earth Observation satellite data. To maximize the

  12. Wastewater effluent dispersal in Southern California Bays

    KAUST Repository

    Uchiyama, Yusuke; Idica, Eileen Y.; McWilliams, James C.; Stolzenbach, Keith D.

    2014-01-01

    The dispersal and dilution of urban wastewater effluents from offshore, subsurface outfalls is simulated with a comprehensive circulation model with downscaling in nested grid configurations for San Pedro and Santa Monica Bays in Southern California during Fall of 2006. The circulation is comprised of mean persistent currents, mesoscale and submesoscale eddies, and tides. Effluent volume inflow rates at Huntington Beach and Hyperion are specified, and both their present outfall locations and alternative nearshore diversion sites are assessed. The effluent tracer concentration fields are highly intermittent mainly due to eddy currents, and their probability distribution functions have long tails of high concentration. The dilution rate is controlled by submesoscale stirring and straining in tracer filaments. The dominant dispersal pattern is alongshore in both directions, approximately along isobaths, over distances of more than 10. km before dilution takes over. The current outfall locations mostly keep the effluent below the surface and away from the shore, as intended, but the nearshore diversions do not. © 2014 Elsevier Ltd.

  13. Recent Results from the Daya Bay Experiment

    Science.gov (United States)

    Yu, Z. Y.; Daya Bay Collaboration

    2017-09-01

    The Daya Bay reactor neutrino experiment was designed to precisely measure the neutrino oscillation parameter θ 13 via the relative comparison of neutrino rates and spectra at different baselines. Eight identically designed detectors were deployed in two near experimental halls and a far hall. Six 2.9 GWth nuclear power reactors served as intense {\\bar ν _e} sources. Since Dec. 2011, the experiment has been running stably. The latest neutrino oscillation results were based on 1230 days of data. Analysis using a three-flavor oscillation model yielded sin22θ 13 = 0.0841 ± 0.0027(stat.) ± 0.0019(syst.), and effective neutrino mass-squared difference ≤ft| {Δ mee^2} \\right| = ≤ft( {2.50 +/- 0.06≤ft( {stat.} \\right) +/- 0.06≤ft( {syst.} \\right)} \\right) × {10 - 3}e{V^2}. Besides, results from the absolute measurement of reactor {\\bar ν _e} flux and energy spectrum, and a search for a light sterile neutrino are also presented.

  14. Holocene Tsunamis in Avachinsky Bay, Kamchatka, Russia

    Science.gov (United States)

    Pinegina, Tatiana K.; Bazanova, Lilya I.; Zelenin, Egor A.; Bourgeois, Joanne; Kozhurin, Andrey I.; Medvedev, Igor P.; Vydrin, Danil S.

    2018-04-01

    This article presents results of the study of tsunami deposits on the Avachinsky Bay coast, Kurile-Kamchatka island arc, NW Pacific. We used tephrochronology to assign ages to the tsunami deposits, to correlate them between excavations, and to restore paleo-shoreline positions. In addition to using established regional marker tephra, we establish a detailed tephrochronology for more local tephra from Avachinsky volcano. For the first time in this area, proximal to Kamchatka's primary population, we reconstruct the vertical runup and horizontal inundation for 33 tsunamis recorded over the past 4200 years, 5 of which are historical events - 1737, 1792, 1841, 1923 (Feb) and 1952. The runup heights for all 33 tsunamis range from 1.9 to 5.7 m, and inundation distances from 40 to 460 m. The average recurrence for historical events is 56 years and for the entire study period 133 years. The obtained data makes it possible to calculate frequencies of tsunamis by size, using reconstructed runup and inundation, which is crucial for tsunami hazard assessment and long-term tsunami forecasting. Considering all available data on the distribution of historical and paleo-tsunami heights along eastern Kamchatka, we conclude that the southern part of the Kamchatka subduction zone generates stronger tsunamis than its northern part. The observed differences could be associated with variations in the relative velocity and/or coupling between the downgoing Pacific Plate and Kamchatka.

  15. [Reflectance of sea ice in Liaodong Bay].

    Science.gov (United States)

    Xu, Zhan-tang; Yang, Yue-zhong; Wang, Gui-fen; Cao, Wen-xi; Kong, Xiang-peng

    2010-07-01

    In the present study, the relationships between sea ice albedo and the bidirectional reflectance distribution in Liaodong Bay were investigated. The results indicate that: (1) sea ice albedo alpha(lambda) is closely related to the components of sea ice, the higher the particulate concentration in sea ice surface is, the lower the sea ice albedo alpha(lambda) is. On the contrary, the higher the bubble concentration in sea ice is, the higher sea ice albedo alpha(lambda) is. (2) Sea ice albedo alpha(lambda) is similar to the bidirectional reflectance factor R(f) when the probe locates at nadir. The R(f) would increase with the increase in detector zenith theta, and the correlation between R(f) and the detector azimuth would gradually increase. When the theta is located at solar zenith 63 degrees, the R(f) would reach the maximum, and the strongest correlation is also shown between the R(f) and the detector azimuth. (3) Different types of sea ice would have the different anisotropic reflectance factors.

  16. Christchurch Bay Tower data archive. Principal report

    Energy Technology Data Exchange (ETDEWEB)

    Bishop, J.R.

    1998-05-01

    Wave force experiments at the Christchurch Bay Tower yielded valuable data on wave forces on cylinders under the complex flows experienced in real sea conditions. The last experiments were conducted in 1987, but the data remain an important source of information on the wave forces on cylinders, together with the measured wave particle kinematics. The use of two columns with different diameters enabled the studies to extend over a large range of Keulegan Carpenter numbers and Reynolds numbers. The experiments included clean vertical and horizontal cylinders, cylinders with real kelp fouling, with simulated hard roughness and a flexible cylinder. Considerable effort was devoted to quality control of the measured data. The experiments were funded mainly by the UK Department of Energy, and ownership of the results has now been transferred to the Offshore Safety Division of the Health and Safety Executive. They have now commissioned the archiving of a set of important records from the experiments, covering clean cylinders, kelp fouling, hard roughness and a horizontal cylinder. The purpose is to make the data available for future work on wave loadings and the related wave particle kinematics. The raw measured data are not usable without specialist decoding, calibration and certain pre-processing tasks. So, in this archiving work, the data have been processed into parameters such as 2 axis forces and 3 axis wave kinematics. As a result of this archiving project the data are available on CD ROM. (author)

  17. Highlights from the Daya Bay Neutrino Experiment

    Directory of Open Access Journals (Sweden)

    Wang Zhe

    2014-04-01

    Full Text Available With an understanding of the energy response of the anti-neutrino detectors, the Daya Bay collaboration presents new results using gadolinium-neutron capture: sin2 2θ13 = 0.108 ± 0.028 and |Δmee2| = 2.55−0.18+0.21 × 10−3 eV2 with only the distortion information of the neutrino energy spectrum shape, and sin2 2θ13 = 0.090−0.009+0.008 and |Δmee2| = 2.59−0.20+0.19 10−3 eV2 with both the shape and event rate information. It is also demonstrated that a clean inverse beta decay sample can be extracted using hydrogen-neutron capture, which is now being used for neutrino oscillation measurement. The supernova online trigger is designed and implemented, which can provide about 100% efficiency for all SN1987A-scale supernova bursts within the Milky Way.

  18. Wastewater effluent dispersal in Southern California Bays

    KAUST Repository

    Uchiyama, Yusuke

    2014-03-01

    The dispersal and dilution of urban wastewater effluents from offshore, subsurface outfalls is simulated with a comprehensive circulation model with downscaling in nested grid configurations for San Pedro and Santa Monica Bays in Southern California during Fall of 2006. The circulation is comprised of mean persistent currents, mesoscale and submesoscale eddies, and tides. Effluent volume inflow rates at Huntington Beach and Hyperion are specified, and both their present outfall locations and alternative nearshore diversion sites are assessed. The effluent tracer concentration fields are highly intermittent mainly due to eddy currents, and their probability distribution functions have long tails of high concentration. The dilution rate is controlled by submesoscale stirring and straining in tracer filaments. The dominant dispersal pattern is alongshore in both directions, approximately along isobaths, over distances of more than 10. km before dilution takes over. The current outfall locations mostly keep the effluent below the surface and away from the shore, as intended, but the nearshore diversions do not. © 2014 Elsevier Ltd.

  19. Mangrove Forest Structure in Ungwana Bay, Kenya

    International Nuclear Information System (INIS)

    Bundotich, G; Karacchi, M.; Kairo, J.G.

    2007-01-01

    Forest structure and natural regeneration was investigated in a 12-year-old Rhizophoria reforested stand at Gazi bay, Kenya. Within 10* 10m 2 plots, tree height and stem diameter at breast height (DBH) of all trees of DBH>2.5 cm were determined. Stand volume was estimated by allometric equations derived from 50 harvested trees. The composition of juveniles was determined by within 5*5 m 2 inside the 10 * 10 plots. The stand density in Rhizophora plantation was 5,132 stems ha - 1, with a mean canopy height and stem diameter of 8.4+ 1 .1 m (range: 3.0 to 11.0 m) and 6.2+ 1 .87 cm (range: 2.5 to 12.4 cm) respectively. The stand volume was 103.80 m 3 ha-1 , stilt roots and branches combined was 43.09 m 3 ha-1 . Five species with juveniles; Rhizophora mucronata, Bruguieria gymnorrhiza, Ceriops tagal, Sonneretia alba and Xylocarpus granatum, were encountered with density of 4 886 juveniles ha-1 , with clustered distribution pattern

  20. Content Abstract Classification Using Naive Bayes

    Science.gov (United States)

    Latif, Syukriyanto; Suwardoyo, Untung; Aldrin Wihelmus Sanadi, Edwin

    2018-03-01

    This study aims to classify abstract content based on the use of the highest number of words in an abstract content of the English language journals. This research uses a system of text mining technology that extracts text data to search information from a set of documents. Abstract content of 120 data downloaded at www.computer.org. Data grouping consists of three categories: DM (Data Mining), ITS (Intelligent Transport System) and MM (Multimedia). Systems built using naive bayes algorithms to classify abstract journals and feature selection processes using term weighting to give weight to each word. Dimensional reduction techniques to reduce the dimensions of word counts rarely appear in each document based on dimensional reduction test parameters of 10% -90% of 5.344 words. The performance of the classification system is tested by using the Confusion Matrix based on comparative test data and test data. The results showed that the best classification results were obtained during the 75% training data test and 25% test data from the total data. Accuracy rates for categories of DM, ITS and MM were 100%, 100%, 86%. respectively with dimension reduction parameters of 30% and the value of learning rate between 0.1-0.5.

  1. Holocene Tsunamis in Avachinsky Bay, Kamchatka, Russia

    Science.gov (United States)

    Pinegina, Tatiana K.; Bazanova, Lilya I.; Zelenin, Egor A.; Bourgeois, Joanne; Kozhurin, Andrey I.; Medvedev, Igor P.; Vydrin, Danil S.

    2018-03-01

    This article presents results of the study of tsunami deposits on the Avachinsky Bay coast, Kurile-Kamchatka island arc, NW Pacific. We used tephrochronology to assign ages to the tsunami deposits, to correlate them between excavations, and to restore paleo-shoreline positions. In addition to using established regional marker tephra, we establish a detailed tephrochronology for more local tephra from Avachinsky volcano. For the first time in this area, proximal to Kamchatka's primary population, we reconstruct the vertical runup and horizontal inundation for 33 tsunamis recorded over the past 4200 years, 5 of which are historical events - 1737, 1792, 1841, 1923 (Feb) and 1952. The runup heights for all 33 tsunamis range from 1.9 to 5.7 m, and inundation distances from 40 to 460 m. The average recurrence for historical events is 56 years and for the entire study period 133 years. The obtained data makes it possible to calculate frequencies of tsunamis by size, using reconstructed runup and inundation, which is crucial for tsunami hazard assessment and long-term tsunami forecasting. Considering all available data on the distribution of historical and paleo-tsunami heights along eastern Kamchatka, we conclude that the southern part of the Kamchatka subduction zone generates stronger tsunamis than its northern part. The observed differences could be associated with variations in the relative velocity and/or coupling between the downgoing Pacific Plate and Kamchatka.

  2. Synoptic volumetric variations and flushing of the Tampa Bay estuary

    Science.gov (United States)

    Wilson, M.; Meyers, S. D.; Luther, M. E.

    2014-03-01

    Two types of analyses are used to investigate the synoptic wind-driven flushing of Tampa Bay in response to the El Niño-Southern Oscillation (ENSO) cycle from 1950 to 2007. Hourly sea level elevations from the St. Petersburg tide gauge, and wind speed and direction from three different sites around Tampa Bay are used for the study. The zonal (u) and meridional (v) wind components are rotated clockwise by 40° to obtain axial and co-axial components according to the layout of the bay. First, we use the subtidal observed water level as a proxy for mean tidal height to estimate the rate of volumetric bay outflow. Second, we use wavelet analysis to bandpass sea level and wind data in the time-frequency domain to isolate the synoptic sea level and surface wind variance. For both analyses the long-term monthly climatology is removed and we focus on the volumetric and wavelet variance anomalies. The overall correlation between the Oceanic Niño Index and volumetric analysis is small due to the seasonal dependence of the ENSO response. The mean monthly climatology between the synoptic wavelet variance of elevation and axial winds are in close agreement. During the winter, El Niño (La Niña) increases (decreases) the synoptic variability, but decreases (increases) it during the summer. The difference in winter El Niño/La Niña wavelet variances is about 20 % of the climatological value, meaning that ENSO can swing the synoptic flushing of the bay by 0.22 bay volumes per month. These changes in circulation associated with synoptic variability have the potential to impact mixing and transport within the bay.

  3. Plant diversity and biomass of Marudu bay mangroves in Malaysia

    International Nuclear Information System (INIS)

    Hanum, F.; Kudus, K.A.; Saari, N.S

    2012-01-01

    The mangroves of Marudu Bay in the state of Sabah is situated at the tip of Borneo Island, and at the southern limit of the Coral Triangle whose waters hold the highest diversity of corals, fish, molluscks, crustaceans and marine plant species in the world. The ecosystem shows a deterioration due to unsustainable fishing, pollution and encroachment, and these are impacting the Marudu Bay coastal communities economically. Fishing is the major economic activity here. Realising the importance of conserving the mangroves to uplift the socio-economic livelihood of the coastal community, a resource inventory of the mangroves and its productivity study were carried out. A total of 16 plant species in 12 genera and 9 families were identified. It was also found that 0.7 ha is capable of capturing all the species in the mangrove forest. The mangrove forests of Marudu Bay are dominated by Rhizopora apiculata and R. mucronata. The highest Importance Value index (IVI) was given by Rhizophora mucronata. Total Above Ground Biomass (TAGB) for 1-ha of mangrove forest in Marudu Bay was estimated to be 98.4 t/ha. It was found in other parallel studies that the mangroves of Marudu Bay are productive ecosystems that provide valuable habitats, nurseries and spawning grounds for various commercially important species of fish and invertebrates such as shrimp besides many species of wildlife. The mangroves at Marudu Bay are not only aesthetically attractive but provide opportunities for ecotourism activities that can be undertaken by the local community inhabiting the area to uplift their meagre income, These activities include mangrove cruising, recreational fishing, educational tourism and mangrove honey production, amongst others. This way, the degradation of the mangrove in Marudu Bay can be halted and reversed. (author)

  4. The exotic mute swan (Cygnus olor) in Chesapeake Bay, USA

    Science.gov (United States)

    Perry, M.C.; Perry, M.C.

    2002-01-01

    The exotic mute swan (Cygnus olor) has increased its population size in Chesapeake Bay (Maryland and Virginia) to approximately 4,500 since 1962 when five swans were released in the Bay. The Bay population of mute swans now represents 30% of the total Atlantic Flyway population (12,600) and has had a phenomenal increase of 1,200% from 1986 to 1999. Unlike the tundra swans (Cygnus columbianus) that migrate to the Bay for the winter, the mute swan is a year-long resident, and, therefore, reports of conflicts with nesting native waterbirds and the consumption of submerged aquatic vegetation (SAV) have raised concerns among resource managers. Populations of black skimmers (Rynchops niger) and least terns (Sterna antillarum) nesting on beaches and oyster shell bars have been eliminated by molting mute swans. Although data on the reduction of SAV by nesting mute swans and their offspring during the spring and summer are limited, food habits data show that mute swans rely heavily on SAV during these months. Widgeon grass (Ruppia maritima) constituted 56% and eel grass (Zostera marina) constituted 43% of the gullet food of mute swans. Other SAV and invertebrates (including bryozoans, shrimp, and amphipods) formed a much smaller amount of the food percentage (1%). Invertebrates are believed to have been selected accidently within the vegetation eaten by the swans. Corn (Zea mays) fed to swans by Bay residents during the winter probably supplement limited vegetative food resources in late winter. A program to control swan numbers by the addling of eggs and the killing of adult swans has been a contentious issue with some residents of the Bay area. A management plan is being prepared by a diverse group of citizens appointed by the Governor to advise the Maryland Department of Natural Resources on viable and optimum options to manage mute swans in the Maryland portion of Chesapeake Bay. Hopefully, the implementation of the plan will alleviate the existing conflicts to the

  5. A field study of littoral processes in Estero Bay, California

    Science.gov (United States)

    Dingler, J.R.; Anima, R.J.; Molzan, D.E.; Luepke, Gretchen; Peterson, C.L.

    1982-01-01

    Estero Bay, which lies on the central California coast, has rocky headlands at both ends and sandy beaches within it. The shoreline of the bay has adjusted to be in equilibrium with the predominant wave climate, which is from the northwest. Because of its present shoreline configuration, the net southward littoral transport found along much of the California coast does not occur within Estero Bay. Instead, the sand primarily moves on- and offshore with a reversing longshore component. This sand transport pattern produces a littoral cell within Estero Bay even though there is no submarine canyon in the area. The primary sand sinks for this cell appear to be the sand spit south of Morro Rock and the entrance to Morro Bay itself, although this opinion was not experimentally verified. Field work during one summer (1978) and the following winter (1979) produced baseline data on the profile of and grain-size distribution across the littoral zone. In the offshore part of the littoral zone we also studied ripple size and type, internal structure, depth of erosion, and mineralogy. Although these data, which were collected along nine transects spaced 2 km apart, are inadequate to yield transport and energy rates, they indicate a northward decrease in wave energy within Estero Bay and a mixing of the sediments in the offshore. Box core and rod height data from grid points in seven meters of water showed that on the order of a meter of erosion occurred in the central part of the bay between the two sampling periods. Offshore, the data were incomplete, but at one station, in 17 m of water, at least 20 cm of erosion occurred.

  6. 137Cs and 210Pb distribution in Manila Bay sediment

    International Nuclear Information System (INIS)

    Sta. Maria, Efren J.; Madrid, Jordan F.; Olivares, Ryan U.; Bulos, Adelina DM; Dayaon, Jennyvi P.; Asa, Anie Day DC; Sombrito, Elvira Z.

    2011-01-01

    Two radionuclides were measured in surface sediment samples taken from geographically distributed sections of Manila Bay, namely cesium-137 ( 137 Cs) and lead-210 ( 210 Pb). Results indicated a noticeable change in the radioactivity concentration levels in sediments collected in 2005 and 2010, with a median concentration of 1.0 and 2.64 Bq kg -1 , respectively. Higher levels of 137 Cs radioactivity were measured in the northern and inner portion of the bay adjacent to major river systems, agricultural and highly industrialized urban areas. 137 Cs isotope increased in activity in most of the samples especially in the northwestern areas of Bataan and Pampanga with five times more than the activity from the first sampling measurements. Nevertheless, radioactivity concentrations observed in surface sediments along the bay are within the range of radioactivity in several areas monitored in the Northern Hemisphere. The country has been frequented by tropical cyclones and storms that have caused erosion, which may have introduced elevated material input in the bay. In addition, wind-driven circulation especially in the shallower areas of the bay is a possibility for the substantial sediment movement and accumulation along this coast. Conversely, areas with higher 137 Cs have lower values of 210 Pb. In an undisturbed environment, 210 Pb deposition values are assumed nearly constant. Hence, changes in the radioactivity concentration levels of these radionuclides can be an indicator of pollution input from land-based sources, sediment movement and reworking in the coastal areas. At present, there is very limited information on the radioactivity level of various radioisotopes in Manila Bay.The data obtained are benchmark values against which changes that will be occurring in the bay can be assessed. (author)

  7. Abundance patterns of macrofauna and infauna in nursery habitats of Christmas Bay, Texas: July 1984 through June 1985.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Between July 1984 and June 1985, monthly samples were collected from marsh, seagrass, and nonvegetated habitats in Christmas Bay and West Bay in the Galveston Bay...

  8. One big rig, two valuable functions

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2004-11-01

    A hybrid coil tubing and conventional workover rig, tailor-made for conditions on Alaska's remote North Slope is described. The dual function rig, owned by BP Exploration, towers 142 feet above the barren Arctic tundra, and weighs between 1.5 and 2 million pounds, rests on eight enormous wheels that stand 11.5 feet tall and 3.5 feet wide, and is supported by 64 smaller tires in between. The rig includes the hybrid coiled tubing rig and a conventional workover rig; it exerts less than 100 pounds per square inch of pressure on the tender Arctic surface as it moves forward at a top speed of two miles per hour. It is considered by its developers as the next-step change in providing cost-effective access to reserves in the large, mature and remote oilfields such as those of Alaska's Prudhoe Bay. The rig is the product of cooperation between Schlumberger expertise in coiled tubing drilling and Nordic-Calista's know-how of jointed pipe operations and operating rigs in an Arctic environment. It is the first time in Prudhoe Bay, and probably in the world, that a coiled tubing unit was installed on a rig to do coiled-tubing sidetracks, i.e to drill a secondary wellbore away from the original wellbore. Since the first unit was commissioned in 1996, the rig has drilled 280 wells. Rig No. 2, much improved and commissioned in 2002, drilled about 30 wells to date. Unlike Rig No, 1, Rig No. 2 can change reels without a crane, and it has a hydraulic pipe skate that moves jointed pipe to and from the rig floor without human aid. The expectation is that using this rig it will be possible to do micro-hole exploration drilling on the North Slope (i.e. drilling a small surface hole with jointed pipe and then switch to coiled tubing), substantially cutting the cost of exploration.

  9. Organic carbon balance and net ecosystem metabolism in Chesapeake Bay

    Science.gov (United States)

    Kemp, W.M.; Smith, E.M.; Marvin-DiPasquale, M.; Boynton, W.R.

    1997-01-01

    The major fluxes of organic carbon associated with physical transport and biological metabolism were compiled, analyzed and compared for the mainstem portion of Chesapeake Bay (USA). In addition, 5 independent methods were used to calculate the annual mean net ecosystem metabolism (NEM = production - respiration) for the integrated Bay. These methods, which employed biogeochemical models, nutrient mass-balances anti summation of individual organic carbon fluxes, yielded remarkably similar estimates, with a mean NEM of +50 g C m-2 yr-1 (?? SE = 751, which is approximately 8% of the estimated annual average gross primary production. These calculations suggest a strong cross-sectional pattern in NEM throughout the Bay, wherein net heterotrophic metabolism prevails in the pelagic zones of the main channel, while net autotrophy occurs in the littoral zones which flank the deeper central area. For computational purposes, the estuary was separated into 3 regions along the land-sea gradient: (1) the oligohaline Upper Bay (11% of total area); (2) the mesohaline Mid Bay (36% of area); and (3) the polyhaline Lower Bay (53% of area). A distinct regional trend in NEM was observed along this salinity gradient, with net here(atrophy (NEM = 87 g C m-2 yr-1) in the Upper Bay, balanced metabolism in the Mid Bay and net autotrophy (NEM = +92 g C m-2 yr-1) in the Lower Bay. As a consequence of overall net autotrophy, the ratio of dissolved inorganic nitrogen (DIN) to total organic nitrogen (TON) changed from DIN:TON = 5.1 for riverine inputs to DIN:TON = 0.04 for water exported to the ocean. A striking feature of this organic C mass-balance was the relative dominance of biologically mediated metabolic fluxes compared to physical transport fluxes. The overall ratio of physical TOC inputs (1) to biotic primary production (P) was 0.08 for the whole estuary, but varied dramatically from 2.3 in the Upper Bay to 0.03 in the Mid and Lower Bay regions. Similarly, ecosystem respiration was

  10. Spatial and temporal characterizations of water quality in Kuwait Bay.

    Science.gov (United States)

    Al-Mutairi, N; Abahussain, A; El-Battay, A

    2014-06-15

    The spatial and temporal patterns of water quality in Kuwait Bay have been investigated using data from six stations between 2009 and 2011. The results showed that most of water quality parameters such as phosphorus (PO4), nitrate (NO3), dissolved oxygen (DO), and Total Suspended Solids (TSS) fluctuated over time and space. Based on Water Quality Index (WQI) data, six stations were significantly clustered into two main classes using cluster analysis, one group located in western side of the Bay, and other in eastern side. Three principal components are responsible for water quality variations in the Bay. The first component included DO and pH. The second included PO4, TSS and NO3, and the last component contained seawater temperature and turbidity. The spatial and temporal patterns of water quality in Kuwait Bay are mainly controlled by seasonal variations and discharges from point sources of pollution along Kuwait Bay's coast as well as from Shatt Al-Arab River. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Heavy Metal Pollution Evolution in Sediments from Urdaibai Bay (Spain)

    International Nuclear Information System (INIS)

    Soto, J.; Soto, J.A.; Corral, D.; Gelen, A.; Diaz, O.; Navas, A.

    2003-01-01

    Full Text: The Urdaibai bay is a biosphere reservoir located in the north of Spain. The mayor components of bay sediments come from marls and clays eroded which are deposited together with metallic pollutants present in water, air and rain. For this reason it is possible to study the temporal evolution of the bay pollution by measuring the heavy metal concentrations in the sediments and considering the correspondence with its age. To this aim, sediments cores were taken in two different points of the Urdaibai bay. The cores were cut into 1 cm thick horizontal sections. Sediment dating was performed using a low background gamma spectrometry with GeHP to determine Cs-137, Ra-226 and Pb-210 activities and applying the CIC and CRS models. The heavy metal concentrations in sediments were determined by ICP-MS. The obtained results in one of the studied positions show an increment of the Pb, Zn, Ni, Cu and Cr concentrations in the first 10 cm of the sediment core. This fact can be related to an increase of the bay pollution in the last 100 years. In the second studied core the heavy metal concentrations are constant in depth or lower in the superficial layers. This could be due to an increment the deposition rate of eroded material

  12. Derivation of Delaware Bay tidal parameters from space shuttle photography

    International Nuclear Information System (INIS)

    Zheng, Quanan; Yan, Xiaohai; Klemas, V.

    1993-01-01

    The tide-related parameters of the Delaware Bay are derived from space shuttle time-series photographs. The water areas in the bay are measured from interpretation maps of the photographs with a CALCOMP 9100 digitizer and ERDAS Image Processing System. The corresponding tidal levels are calculated using the exposure time annotated on the photographs. From these data, an approximate function relating the water area to the tidal level at a reference point is determined. Based on the function, the water areas of the Delaware Bay at mean high water (MHW) and mean low water (MLW), below 0 m, and for the tidal zone are inferred. With MHW and MLW areas and the mean tidal range, the authors calculate the tidal influx of the Delaware Bay, which is 2.76 x 1O 9 m 3 . Furthermore, the velocity of flood tide at the bay mouth is determined using the tidal flux and an integral of the velocity distribution function at the cross section between Cape Henlopen and Cape May. The result is 132 cm/s, which compares well with the data on tidal current charts

  13. Causal Bayes Model of Mathematical Competence in Kindergarten

    Directory of Open Access Journals (Sweden)

    Božidar Tepeš

    2016-06-01

    Full Text Available In this paper authors define mathematical competences in the kindergarten. The basic objective was to measure the mathematical competences or mathematical knowledge, skills and abilities in mathematical education. Mathematical competences were grouped in the following areas: Arithmetic and Geometry. Statistical set consisted of 59 children, 65 to 85 months of age, from the Kindergarten Milan Sachs from Zagreb. The authors describe 13 variables for measuring mathematical competences. Five measuring variables were described for the geometry, and eight measuring variables for the arithmetic. Measuring variables are tasks which children solved with the evaluated results. By measuring mathematical competences the authors make causal Bayes model using free software Tetrad 5.2.1-3. Software makes many causal Bayes models and authors as experts chose the model of the mathematical competences in the kindergarten. Causal Bayes model describes five levels for mathematical competences. At the end of the modeling authors use Bayes estimator. In the results, authors describe by causal Bayes model of mathematical competences, causal effect mathematical competences or how intervention on some competences cause other competences. Authors measure mathematical competences with their expectation as random variables. When expectation of competences was greater, competences improved. Mathematical competences can be improved with intervention on causal competences. Levels of mathematical competences and the result of intervention on mathematical competences can help mathematical teachers.

  14. Phytoplankton and nutrient dynamics in Winyah Bay, SC.

    Science.gov (United States)

    Boneillo, G. E.; Brooks, S. S.; Brown, S. L.; Woodford, K. M.; Wright, C. R.

    2016-02-01

    Winyah Bay is a coastal plain estuary located in South Carolina that has been classified for a moderate risk of Eutrophication by NOAA. Winyah Bay receives freshwater input from four rivers, the Waccamaw, Sampit, Black, and Pee Dee Rivers. The Waccamaw, Sampit and Black River are blackwater systems that discharge elevated amounts of colored dissolved organic matter. During the summer and fall of 2015, bioassay experiments were performed to simultaneously examine both light and nutrient (nitrogen & phosphate) limitation throughout Winyah Bay. Sampling stations near the mouth of the Waccamaw and Sampit Rivers showed that phytoplankton were light limited in the late summer instead of nutrient limited. These stations were located in the industrialized area of the bay and typically had the highest nutrient concentrations and highest turbidity, with Secchi depths typically less than 0.5 meters. Results indicated that phytoplankton may be nitrogen limited near the mouth of Winyah Bay, where nutrient concentrations and turbidity were observed to be lower than locations further upstream. There was also an observed dissolved oxygen and pH gradient during the summer of 2015. Dissolved oxygen levels less than 4.0 mg/L were routinely observed near the industrialized head of the estuary and corresponded with lower pH values.

  15. Wave-current interaction in Willapa Bay

    Science.gov (United States)

    Olabarrieta, Maitane; Warner, John C.; Kumar, Nirnimesh

    2011-01-01

    This paper describes the importance of wave-current interaction in an inlet-estuary system. The three-dimensional, fully coupled, Coupled Ocean-Atmosphere-Wave-Sediment Transport (COAWST) modeling system was applied in Willapa Bay (Washington State) from 22 to 29 October 1998 that included a large storm event. To represent the interaction between waves and currents, the vortex-force method was used. Model results were compared with water elevations, currents, and wave measurements obtained by the U.S. Army Corp of Engineers. In general, a good agreement between field data and computed results was achieved, although some discrepancies were also observed in regard to wave peak directions in the most upstream station. Several numerical experiments that considered different forcing terms were run in order to identify the effects of each wind, tide, and wave-current interaction process. Comparison of the horizontal momentum balances results identified that wave-breaking-induced acceleration is one of the leading terms in the inlet area. The enhancement of the apparent bed roughness caused by waves also affected the values and distribution of the bottom shear stress. The pressure gradient showed significant changes with respect to the pure tidal case. During storm conditions the momentum balance in the inlet shares the characteristics of tidal-dominated and wave-dominated surf zone environments. The changes in the momentum balance caused by waves were manifested both in water level and current variations. The most relevant effect on hydrodynamics was a wave-induced setup in the inner part of the estuary.

  16. Bayes classifiers for imbalanced traffic accidents datasets.

    Science.gov (United States)

    Mujalli, Randa Oqab; López, Griselda; Garach, Laura

    2016-03-01

    Traffic accidents data sets are usually imbalanced, where the number of instances classified under the killed or severe injuries class (minority) is much lower than those classified under the slight injuries class (majority). This, however, supposes a challenging problem for classification algorithms and may cause obtaining a model that well cover the slight injuries instances whereas the killed or severe injuries instances are misclassified frequently. Based on traffic accidents data collected on urban and suburban roads in Jordan for three years (2009-2011); three different data balancing techniques were used: under-sampling which removes some instances of the majority class, oversampling which creates new instances of the minority class and a mix technique that combines both. In addition, different Bayes classifiers were compared for the different imbalanced and balanced data sets: Averaged One-Dependence Estimators, Weightily Average One-Dependence Estimators, and Bayesian networks in order to identify factors that affect the severity of an accident. The results indicated that using the balanced data sets, especially those created using oversampling techniques, with Bayesian networks improved classifying a traffic accident according to its severity and reduced the misclassification of killed and severe injuries instances. On the other hand, the following variables were found to contribute to the occurrence of a killed causality or a severe injury in a traffic accident: number of vehicles involved, accident pattern, number of directions, accident type, lighting, surface condition, and speed limit. This work, to the knowledge of the authors, is the first that aims at analyzing historical data records for traffic accidents occurring in Jordan and the first to apply balancing techniques to analyze injury severity of traffic accidents. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Seafloor studies of Mamala Bay, Honolulu, Hawaii

    Science.gov (United States)

    Torresan, Michael E.

    No comprehensive study of the effects of disposal of dredge spoils has been conducted to determine if the environment has suffered. The U.S. Army Corps of Engineers (USACE) has regularly dredged the shipping channels of Honolulu Harbor and Pearl Harbor for commercial and military purposes. The 5-year frequency for new dredging activity has led to the formation of extensive offshore wide deposits of relatively coarse sediments being created in a sedimentary environment that naturally collects much finer-grained materials. At the same time, the rapid growth of Honolulu and its suburban region over the past 3 decades has added nutrient-enriched sewage outfall to the artificially-heavy sediment load. The combined effects of dredge-spoil disposal and contaminant loads are not well-documented, and are poorly understood. The U.S. Geological Survey (USGS) began a comprehensive study to characterize the seafloor of Mamala Bay.In 1993, the USGS initiated a program sponsored by the USACE and the U.S. Environmental Protection Agency that produced a detailed map of the seafloor, especially of the distribution of dredge spoils, and a preliminary analysis of the environmental effects of dredge-spoils disposal and the chemical effects of the introduction of nutrient-rich outfall. Part of the work would involve sediment sampling, biological testing, and evaluation. Of particular interest is tissue sampling and analysis of endemic shrimp to determine the rates of absorption of toxic elements, such as heavy metals, that are easily brought into the food chain.

  18. 适合于海上油田低伤害有机酸完井液技术研究%Study on the Low Damage Organic Acid Completion Fluid Technology for Offshore Oilfields

    Institute of Scientific and Technical Information of China (English)

    张万栋; 李长城

    2018-01-01

    针对渤海B油田钻井过程中钻井液污染储层等问题,通过向完井液中引入有机酸YJS解除储层堵塞,采用离心法和激光粒度法对其中粘土稳定剂的种类和加量进行了优选,进行了腐蚀性能的测试和缓蚀剂的优选,并对优选的体系与原油和各工作液间的配伍性进行了评价,最终确定有机酸完井液配方为:海水+0.5%有机酸YJS+2.0%粘土稳定剂NWJ +2.0%缓蚀剂HHS;储层保护性能评价实验结果表明,优选的有机酸完井液体系能使污染岩心渗透率恢复值大于115%,不仅能有效地保护储层,同时还能一定程度的改善储层,疏通油流通道.%In order to solve the problem of drilling fluid contaminating reservoirs in drilling process of Bohai B oilfield, introducing organic acid YJS into the completion fluid removed the reservoir blockage caused by early drilling, the centrifugal method and laser particle size method were used to study the effect of clay stabilizer, and the compatibility of the system with crude oil and working fluid was evaluated. The final formulation of organic acid completion fluid was as follows: seawater + 0.5% organic acid YJS + 2.0% clay stabilizer NWJ + 2.0% corrosion inhibitor HHS. Reservoir protection performance evaluation results showed that the preferred organic acid completion fluid system made the recovery rate of contaminated core more than 115%,it not only can effectively protect the reservoir, but also improve the reservoir to a certain extent.

  19. EnviroAtlas - Green Bay, WI - Meter-Scale Urban Land Cover (MULC) Data (2010)

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Green Bay, WI Meter-Scale Urban Land Cover (MULC) dataset comprises 936 km2 around the city of Green Bay, surrounding towns, tribal lands and rural areas in...

  20. Virgin Islands: Coral Bay Watershed Management (A Former EPA CARE Project)

    Science.gov (United States)

    The Coral Bay Watershed Management is a recipient of the Level II CARE cooperative agreement to continue and expand its collective efforts to stop erosion, sediment, and storm-water pollution of Coral Bay, improve solid waste management,

  1. Bristol Bay, Alaska Subarea ESI: T_MAMMAL (Terrestrial Mammal Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for brown bears in the Bristol Bay Subarea. The Subarea includes marine and coastal areas of Bristol Bay...

  2. San Pablo Bay Tidal Marsh Enhancement and Water Quality Improvement Project

    Science.gov (United States)

    Information about the SFBWQP San Pablo Bay Tidal Marsh Enhancement and Water Quality Improvement Project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  3. Mesozooplankton community in the Bay of Bengal (India): Spatial variability during the summer monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, V.; Ramaiah, N.

    Bay had higher mesozooplankton biomass, copepod species richness and diversity than in the Western Bay. Although zooplankton biomass and densities were greater at the eddy stations, correlation between zooplankton and chl a was not statistically...

  4. Is the biological productivity in the Bay of Bengal light limited?

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Narvekar, J.; Nuncio, M.; Kumar, A.; Ramaiah, N.; Sardessai, S.; Gauns, M.; Fernandes, V.; Paul, J.

    Recent measurements of chlorophyll, primary productivity (PP) and nutrients along the central Bay of Bengal (BOB) during summer, fall and spring intermonsoons showed that the northern bay becomes less productive compared to the south in summer...

  5. Lowering Barriers to Achieving Multiple Environmental Goals in the Chesapeake Bay

    Science.gov (United States)

    In recognition of past unsuccessful restoration strategies for the Chesapeake Bay, President Obama signed Executive Order (EO) 13508 “Strategy for Protecting and Restoring the Chesapeake Bay Watershed” in 2009.

  6. South Bay Salt Pond Tidal Marsh Restoration at Pond A17 Project

    Science.gov (United States)

    Information about the SFBWQP South Bay Salt Pond Tidal Marsh Restoration at Pond A17 Project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  7. 76 FR 77780 - Availability of Seats for the Fagatele Bay National Marine Sanctuary Advisory Council

    Science.gov (United States)

    2011-12-14

    ... the Fagatele Bay National Marine Sanctuary Advisory Council AGENCY: Office of National Marine Sanctuaries (ONMS), National Ocean Service (NOS), National Oceanic and Atmospheric Administration (NOAA... applications for the following vacant seats on the Fagatele Bay National Marine Sanctuary Advisory Council...

  8. 76 FR 41763 - Availability of Seats for the Fagatele Bay National Marine Sanctuary Advisory Council

    Science.gov (United States)

    2011-07-15

    ... the Fagatele Bay National Marine Sanctuary Advisory Council AGENCY: Office of National Marine Sanctuaries (ONMS), National Ocean Service (NOS), National Oceanic and Atmospheric Administration (NOAA... applications for the following vacant seats on the Fagatele Bay National Marine Sanctuary Advisory Council...

  9. 75 FR 16075 - Availability of Seats for the Fagatele Bay National Marine Sanctuary Advisory Council

    Science.gov (United States)

    2010-03-31

    ... the Fagatele Bay National Marine Sanctuary Advisory Council AGENCY: Office of National Marine Sanctuaries (ONMS), National Ocean Service (NOS), National Oceanic and Atmospheric Administration (NOAA... applications for the following vacant seats on the Fagatele Bay National Marine Sanctuary Advisory Council...

  10. 75 FR 57442 - Availability of Seats for the Fagatele Bay National Marine Sanctuary Advisory Council

    Science.gov (United States)

    2010-09-21

    ... the Fagatele Bay National Marine Sanctuary Advisory Council AGENCY: Office of National Marine Sanctuaries (ONMS), National Ocean Service (NOS), National Oceanic and Atmospheric Administration (NOAA... applications for the following vacant seats on the Fagatele Bay National Marine Sanctuary Advisory Council...

  11. 77 FR 56190 - Availability of Seats for the Fagatele Bay National Marine Sanctuary Advisory Council

    Science.gov (United States)

    2012-09-12

    ... the Fagatele Bay National Marine Sanctuary Advisory Council AGENCY: Office of National Marine Sanctuaries (ONMS), National Ocean Service (NOS), National Oceanic and Atmospheric Administration (NOAA... applications for the following vacant seat on the Fagatele Bay National Marine Sanctuary Advisory Council...

  12. Strong variability in bacterioplankton abundance and production in central and western Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, V.; Ramaiah, N.; Paul, J.T.; Sardessai, S.; Jyothibabu, R.; Gauns, M.

    to low or no nutrient injections into the surface, primary production in Bay of Bengal is reportedly low. As a consequence, the Bay of Bengal is considered as a region of low biological productivity. Along with many biological parameters, bacterioplankton...

  13. Sediment profile image 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,...

  14. Use of Geographic Information Systems to examine cumulative impacts of development on Mobile Bay, AL and Galveston Bay, TX

    International Nuclear Information System (INIS)

    Rosigno, P.F.; McNiff, M.E.; Watzin, M.C.; Ji, W.

    1993-01-01

    Databases from Mobile Bay, Alabama and Galveston Bay, Texas were compiled using ARC/INFO Geographic Information Systems (GIS) to examine the cumulative impacts from urbanization and industrialization on these two Gulf of Mexico estuaries. The databases included information on wetland habitats, pollution sources, metal contamination, bird-nesting sites, and oyster reefs, among others. A series of maps were used to represent the impacts within and between each ecosystem. These two estuaries share many similarities in the types of developmental pressures that each experience. However, difference in the magnitude of industrial activity, pollution loading, and urban growth coupled with distinct hydrodynamic and geochemical differences in sediment mineralogy, freshwater inflows and salinity regimens results in differing responses. With growing human population and extensive oil and gas development, the demands on Galveston Bay are quite different than those placed on Mobile Bay which has lower growth and less extensive oil and gas infrastructure. Mobile Bay tends to retain whatever contamination enters into the system because of the high levels of clay and organic carbon found in its sediment. Some of these chemicals bioaccumulate, posing an extra risk to natural resources. Geographic Information Systems provide natural resource managers with the technology to manage complex databases. The analytical and mapping capabilities of GIS can be used to consider cumulative effects in a regional context and to develop plans to protect ecologically sensitive areas

  15. Radionuclides and trace elements in middle Chesapeake Bay sediments

    International Nuclear Information System (INIS)

    Gavrilas, M.

    1988-01-01

    Sediments play an important role in aquatic ecology by serving as a repository for radioactive substances and for soluble chemical pollutants that they may transport over considerable distances and may pass to a higher trophic level by way of bottom-feeding biota. The Chesapeake Bay is a moderately stratified, drowned river valley estuary. The oscillatory flood and ebb of the tidal currents are the most obvious motions in the bay and its tributary estuaries. It is considered that the distribution of most of the pollutants, once diluted by the mixing action of the tidal flow, remains relatively constant for many miles up and down the bay. This paper documents the present status of the radioactivity and of trace elements in sediment samples collected in March 1986 from and extended area around the Calvert Cliffs Nuclear Power Plant

  16. The Bias in Bayes and How to Measure it

    Directory of Open Access Journals (Sweden)

    D.A. S. Fraser

    2012-07-01

    Full Text Available A Bayes prior with a likelihood can give approximate confidence and provide a remarkably flexible approach to statistical inference; but is also known to provide inaccurate perhaps incorrect results. We develop a measure of Bayes bias, first examining a simple Normal model and then progressing to quite general models with scalar and vector parameters. The Bias measure can be interpreted as the lateral displacement of the location standardized likelihood function and thus provides ready access to the effect of a prior on p-values, confidence bounds, and Bayes posterior bounds. The needed computation is comparable to that for the likelihood function and thus provides an initial option for checking merits of Bayesian computation for high dimensions.

  17. Norway's role in international collaboration towards rehabilitation of Andreeva Bay.

    Science.gov (United States)

    Dowdall, M; Sneve, M; Standring, W J F; Amundsen, I

    2009-12-01

    Andreeva Bay is one of the largest and most hazardous nuclear legacy sites in northwest Russia. The site is the location of large amounts of Spent Nuclear Fuel (SNF) and radioactive wastes and the risks associated with the site have precipitated an extensive international collaborative effort towards securing and rehabilitating the site. Given the location and proximity of the site, Norway has and continues to contribute in a number of ways towards this effort. Norway's activities in relation to rehabilitative efforts at Andreeva Bay are focused on both infrastructural and remediative initiatives as well as regulatory collaboration with Russia towards ensuring effective and safe operations during handling and removal of SNF and radioactive materials. This article describes Norway's role within international efforts in the context of the rehabilitation of Andreeva Bay and outlines previous activities and Norway's future direction with respect to the site.

  18. Bay State announces growth strategies to cope with changes

    International Nuclear Information System (INIS)

    Anon.

    1996-01-01

    A top executive for New England's biggest independent gas distributor says deregulation of the utility industry offers unprecedented opportunities for growth, but getting there will radically change the way it does business. To achieve dramatic growth, Bay State Gas Co. needs to base their strategies on anticipating the changes in the industry and aggressively positioning themselves to capture the new opportunities that the new business environment is creating. This includes: accelerating the unbundling of transportation service all the way to the residential customer level; forging strategic relationships with retail energy product and service companies as a means of increasing throughput on Bay State's system; implementing performance-based rates that provide financial incentives for lowering costs and improving customer service; accelerating the implementation of sophisticated information systems to streamline key business processes; and aggressively expanding Bay State's nonregulated Energy Products and Services business. These steps are discussed

  19. Seabird colonies in the Melville Bay, Northwest Greenland

    DEFF Research Database (Denmark)

    Boertmann, David; Huffeldt, Nicholas Per

    This report describes the results of a survey for breeding and colonial seabirds in a hitherto un-surveyed area of Northwest Greenland - the Melville Bay. The results shall be included as background data for oil spill sensitivity mapping, preparation of environmental impact assessments of petroleum...... activities in Baffin Bay and for the regulation (by the Greenland government) of petroleum activities. The survey showed, that compared to other coasts of West Greenland, the Melville Bay holds only few breeding colonies and low numbers of breeding seabirds. The most widespread and numerous species...... is the black guillemot followed by the glaucous gull. However, one colony is of national significance – Sabine Øer, with high numbers of breeding Arctic terns and Sabine’s gulls. Other noteworthy observations were puffins on Thom Ø and many new Iceland gull colonies that extended the known northern breeding...

  20. The inauguration of Robert-Bourassa Park at James Bay

    International Nuclear Information System (INIS)

    Valiquette, M.

    1997-01-01

    Robert Bourassa's contributions to the hydroelectric development at James Bay were acknowledged with the inauguration of a park in the ex-prime minister's name. Phase 1 of the James Bay hydroelectric project constituted the world's biggest construction site, employing more than 180,000 people from beginning to project completion. The James Bay project allowed Hydro-Quebec to gain one of the world's largest electric power utilities and to gain significant competitive edge over its competitors. The Robert Bourassa Park contains a picnic area and a visitor interpretation centre which describes the history of the project. A sequence of 5 signposts summarize the contributions that Robert Bourassa made to the megaproject which cost over $20.6 billion. The complex consists of 65 turbines which produce 15,235 megawatts of electricity. 1 fig