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Sample records for hydrocarbon reservoirs leakage

  1. Gravity observations for hydrocarbon reservoir monitoring

    NARCIS (Netherlands)

    Glegola, M.A.

    2013-01-01

    In this thesis the added value of gravity observations for hydrocarbon reservoir monitoring and characterization is investigated. Reservoir processes and reservoir types most suitable for gravimetric monitoring are identified. Major noise sources affecting time-lapse gravimetry are analyzed. The

  2. How secure is subsurface CO2 storage? Controls on leakage in natural CO2 reservoirs

    Science.gov (United States)

    Miocic, Johannes; Gilfillan, Stuart; McDermott, Christopher; Haszeldine, Stuart

    2014-05-01

    Carbon Capture and Storage (CCS) is the only industrial scale technology available to directly reduce carbon dioxide (CO2) emissions from fossil fuelled power plants and large industrial point sources to the atmosphere. The technology includes the capture of CO2 at the source and transport to subsurface storage sites, such as depleted hydrocarbon reservoirs or saline aquifers, where it is injected and stored for long periods of time. To have an impact on the greenhouse gas emissions it is crucial that there is no or only a very low amount of leakage of CO2 from the storage sites to shallow aquifers or the surface. CO2 occurs naturally in reservoirs in the subsurface and has often been stored for millions of years without any leakage incidents. However, in some cases CO2 migrates from the reservoir to the surface. Both leaking and non-leaking natural CO2 reservoirs offer insights into the long-term behaviour of CO2 in the subsurface and on the mechanisms that lead to either leakage or retention of CO2. Here we present the results of a study on leakage mechanisms of natural CO2 reservoirs worldwide. We compiled a global dataset of 49 well described natural CO2 reservoirs of which six are leaking CO2 to the surface, 40 retain CO2 in the subsurface and for three reservoirs the evidence is inconclusive. Likelihood of leakage of CO2 from a reservoir to the surface is governed by the state of CO2 (supercritical vs. gaseous) and the pressure in the reservoir and the direct overburden. Reservoirs with gaseous CO2 is more prone to leak CO2 than reservoirs with dense supercritical CO2. If the reservoir pressure is close to or higher than the least principal stress leakage is likely to occur while reservoirs with pressures close to hydrostatic pressure and below 1200 m depth do not leak. Additionally, a positive pressure gradient from the reservoir into the caprock averts leakage of CO2 into the caprock. Leakage of CO2 occurs in all cases along a fault zone, indicating that

  3. Gravity observations for hydrocarbon reservoir monitoring

    NARCIS (Netherlands)

    Glegola, M.A.

    2013-01-01

    In this thesis the added value of gravity observations for hydrocarbon reservoir monitoring and characterization is investigated. Reservoir processes and reservoir types most suitable for gravimetric monitoring are identified. Major noise sources affecting time-lapse gravimetry are analyzed. The ad

  4. Numerical modeling of temperature and species distributions in hydrocarbon reservoirs

    Science.gov (United States)

    Bolton, Edward W.; Firoozabadi, Abbas

    2014-01-01

    We examine bulk fluid motion and diffusion of multicomponent hydrocarbon species in porous media in the context of nonequilibrium thermodynamics, with particular focus on the phenomenology induced by horizontal thermal gradients at the upper and lower horizontal boundaries. The problem is formulated with respect to the barycentric (mass-averaged) frame of reference. Thermally induced convection, with fully time-dependent temperature distributions, can lead to nearly constant hydrocarbon composition, with minor unmixing due to thermal gradients near the horizontal boundaries. Alternately, the composition can be vertically segregated due to gravitational effects. Independent and essentially steady solutions have been found to depend on how the compositions are initialized in space and may have implications for reservoir history. We also examine injection (to represent filling) and extraction (to represent leakage) of hydrocarbons at independent points and find a large distortion of the gas-oil contact for low permeability.

  5. Assessment of leakage from an engineered reservoir using hydrogeological tools

    Energy Technology Data Exchange (ETDEWEB)

    Smerdon, B.D.; Mendoza, C.A. [Alberta Univ., Edmonton, AB (Canada); McCann, A.; Kraushar, C. [Omni-McCann Consultants Ltd., Edmonton, AB (Canada); Nilson, A. [Alberta Infrastructure, Edmonton, AB (Canada)

    2003-07-01

    Seepage from earth-filled dams can be determined using steady-state, cross sectional, flow net analysis or transient response to fluid pressure within dam construction materials. This paper described the methods used to quantify leakage from a surface-water reservoir (Pine Coulee) located in southern Alberta. The methods included buried valley aquifer tests, three-dimensional groundwater flow simulations and stable isotope water samples. The aquifer tests were conducted when the reservoir was maintained at leaking elevation as well as when it was at non-leaking elevation. When the reservoir was leaking, the results showed a recharge boundary condition in the aquifer. When the reservoir was not leaking, a barrier boundary was present. To verify field-measured parameters and to determine the hydraulic properties and location of the leakage zone, three-dimensional groundwater flow simulations were calibrated to the datasets. Stable isotopes confirmed the seepage of reservoir water to the aquifer. Seepage rates and the required aquifer pumping rates to control aquifer water levels were predicted by the model. The results were in good agreement with field observations since relief well installation. The use of hydrogeological tools proved to be diagnostic and predictive in assessing the subsurface dynamics associated with man-made reservoirs. 15 refs., 2 tabs., 6 figs.

  6. Geophysical monitoring in a hydrocarbon reservoir

    Science.gov (United States)

    Caffagni, Enrico; Bokelmann, Goetz

    2016-04-01

    Extraction of hydrocarbons from reservoirs demands ever-increasing technological effort, and there is need for geophysical monitoring to better understand phenomena occurring within the reservoir. Significant deformation processes happen when man-made stimulation is performed, in combination with effects deriving from the existing natural conditions such as stress regime in situ or pre-existing fracturing. Keeping track of such changes in the reservoir is important, on one hand for improving recovery of hydrocarbons, and on the other hand to assure a safe and proper mode of operation. Monitoring becomes particularly important when hydraulic-fracturing (HF) is used, especially in the form of the much-discussed "fracking". HF is a sophisticated technique that is widely applied in low-porosity geological formations to enhance the production of natural hydrocarbons. In principle, similar HF techniques have been applied in Europe for a long time in conventional reservoirs, and they will probably be intensified in the near future; this suggests an increasing demand in technological development, also for updating and adapting the existing monitoring techniques in applied geophysics. We review currently available geophysical techniques for reservoir monitoring, which appear in the different fields of analysis in reservoirs. First, the properties of the hydrocarbon reservoir are identified; here we consider geophysical monitoring exclusively. The second step is to define the quantities that can be monitored, associated to the properties. We then describe the geophysical monitoring techniques including the oldest ones, namely those in practical usage from 40-50 years ago, and the most recent developments in technology, within distinct groups, according to the application field of analysis in reservoir. This work is performed as part of the FracRisk consortium (www.fracrisk.eu); this project, funded by the Horizon2020 research programme, aims at helping minimize the

  7. Adsorption of hydrocarbons in chalk reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Madsen, L.

    1996-12-31

    The present work is a study on the wettability of hydrocarbon bearing chalk reservoirs. Wettability is a major factor that influences flow, location and distribution of oil and water in the reservoir. The wettability of the hydrocarbon reservoirs depends on how and to what extent the organic compounds are adsorbed onto the surfaces of calcite, quartz and clay. Organic compounds such as carboxylic acids are found in formation waters from various hydrocarbon reservoirs and in crude oils. In the present investigation the wetting behaviour of chalk is studied by the adsorption of the carboxylic acids onto synthetic calcite, kaolinite, quartz, {alpha}-alumina, and chalk dispersed in an aqueous phase and an organic phase. In the aqueous phase the results clearly demonstrate the differences between the adsorption behaviour of benzoic acid and hexanoic acid onto the surfaces of oxide minerals and carbonates. With NaCl concentration of 0.1 M and with pH {approx_equal} 6 the maximum adsorption of benzoic acid decreases in the order: quartz, {alpha}-alumina, kaolinite. For synthetic calcite and chalk no detectable adsorption was obtaind. In the organic phase the order is reversed. The maximum adsorption of benzoic acid onto the different surfaces decreases in the order: synthetic calcite, chalk, kaolinite and quartz. Also a marked difference in adsorption behaviour between probes with different functional groups onto synthetic calcite from organic phase is observed. The maximum adsorption decreases in the order: benzoic acid, benzyl alcohol and benzylamine. (au) 54 refs.

  8. On Leakage from Geologic Storage Reservoirs of CO2

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, Karsten

    2006-02-14

    Large amounts of CO2 would need to be injected underground to achieve a significant reduction of atmospheric emissions. The large areal extent expected for CO2 plumes makes it likely that caprock imperfections will be encountered, such as fault zones or fractures, which may allow some CO2 to escape from the primary storage reservoir. Leakage of CO2 could also occur along wellbores. Concerns with escape of CO2 from a primary geologic storage reservoir include (1) acidification of groundwater resources, (2) asphyxiation hazard when leaking CO2 is discharged at the land surface, (3) increase in atmospheric concentrations of CO2, and (4) damage from a high-energy, eruptive discharge (if such discharge is physically possible). In order to gain public acceptance for geologic storage as a viable technology for reducing atmospheric emissions of CO2, it is necessary to address these issues and demonstrate that CO2 can be injected and stored safely in geologic formations.

  9. Investigation of Underground Hydrocarbon Leakage using Ground Penetrating Radar

    Science.gov (United States)

    Srigutomo, Wahyu; Trimadona; Agustine, Eleonora

    2016-08-01

    Ground Penetrating Radar (GPR) survey was carried out in several petroleum plants to investigate hydrocarbon contamination beneath the surface. The hydrocarbon spills are generally recognized as Light Non-Aqueous Phase Liquids (LNAPL) if the plume of leakage is distributed in the capillary fringe above the water table and as Dense Non-Aqueous Phase Liquids (DNAPL) if it is below the water table. GPR antennas of 200 MHz and 400 MHz were deployed to obtain clear radargrams until 4 m deep. In general, the interpreted radargram sections indicate the presence of surface concrete layer, the compacted silty soill followed by sand layer and the original clayey soil as well as the water table. The presence of hydrocarbon plumes are identified as shadow zones (radar velocity and intensity contrasts) in the radargram that blur the layering pattern with different intensity of reflected signal. Based on our results, the characteristic of the shadow zones in the radargram is controlled by several factors: types of hydrocarbon (fresh or bio-degraded), water moisture in the soil, and clay content which contribute variation in electrical conductivity and dielectric constants of the soil.

  10. Green Methodologies to Test Hydrocarbon Reservoirs

    Directory of Open Access Journals (Sweden)

    Francesca Verga

    2010-01-01

    Full Text Available Problem statement: The definition and the economic viability of the best development strategy of a hydrocarbon reservoir mainly depend on the quantity and type of fluids and on the well productivity. Well testing, consisting in producing hydrocarbon to the surface while measuring the pressure variations induced in the reservoir, has been used for decades to determine the fluid nature and well potential. In exploration and appraisal scenarios the hydrocarbons produced during a test are flared, contributing to the emissions of greenhouse gases. Approach: Due to more stringent environmental regulations and a general need for reduced operating expenses, the current industry drivers in today’s formation evaluation methodologies demand short, safe, cost-effective and environmentally friendly test procedures, especially when conventional tests are prohibitively expensive, logistically not feasible or no surface emissions are allowed. Different methods have been proposed or resuscitated in the last years, such as wireline formation tests, closed chamber tests, production/reinjection tests and injection tests, as viable alternatives to conventional well testing. Results: While various short-term tests, test procedures and interpretation methods are apparently available for conducting successful tests without hydrocarbon production at the surface, clarity is lacking for specific applications of these techniques. An attempt to clarify advantages and limitations of each methodology, particularly with respect to the main testing target is pursued in this study. Specific insight is provided on injection testing, which is one of the most promising methodology to replace traditional well testing in reservoir characterization, except for the possibility to sample the formation fluids. Conclusion/Recommendations: Not a single one method but a combination of more methodologies, in particular injection testing and wireline formation testing, is the most promising

  11. Enhancement of seismic monitoring in hydrocarbon reservoirs

    Science.gov (United States)

    Caffagni, Enrico; Bokelmann, Götz

    2017-04-01

    Hydraulic Fracturing (HF) is widely considered as one of the most significant enablers of the successful exploitation of hydrocarbons in North America. Massive usage of HF is currently adopted to increase the permeability in shale and tight-sand deep reservoirs, despite the economical downturn. The exploitation success is less due to the subsurface geology, but in technology that improves exploration, production, and decision-making. This includes monitoring of the reservoir, which is vital. Indeed, the general mindset in the industry is to keep enhancing seismic monitoring. It allows understanding and tracking processes in hydrocarbon reservoirs, which serves two purposes, a) to optimize recovery, and b) to help minimize environmental impact. This raises the question of how monitoring, and especially seismic techniques could be more efficient. There is a pressing demand from seismic service industry to evolve quickly and to meet the oil-gas industry's changing needs. Nonetheless, the innovative monitoring techniques, to achieve the purpose, must enhance the characterization or the visualization of a superior-quality images of the reservoir. We discuss recent applications of seismic monitoring in hydrocarbon reservoirs, detailing potential enhancement and eventual limitations. The aim is to test the validity of these seismic monitoring techniques, qualitatively discuss their potential application to energy fields that are not only limited to HF. Outcomes from our investigation may benefit operators and regulators in case of future massive HF applications in Europe, as well. This work is part of the FracRisk consortium (www.fracrisk.eu), funded by the Horizon2020 research programme, whose aims is to help minimize the environmental footprint of the shale-gas exploration and exploitation.

  12. Ordovician Basement Hydrocarbon Reservoirs in the Tarim Basin, China

    Institute of Scientific and Technical Information of China (English)

    YAN Xiangbin; LI Tiejun; ZHANG Tao

    2004-01-01

    Ordovician marine carbonate basement traps are widely developed in the paleo-highs and paleo-slopes in the Tarim Basin. Reservoirs are mainly altered pore-cavity-fissure reservoirs. Oil sources are marine carbonate rocks of the Lower Paleozoic. Thus, the paleo-highs and paleo-slopes have good reservoiring conditions and they are the main areas to explore giant and large-scale oil reservoirs. The main factors for their reservoiring are: (1) Effective combination of fenestral pore-cavity-fracture reservoirs, resulting from multi-stage, multi-cyclic karstification (paleo-hypergene and deep buried) and fracturing, with effective overlying seals, especially mudstone and gypsum mudstone in the Carboniferous Bachu Formation, is essential to hydrocarbon reservoiring and high and stable production; (2) Long-term inherited large rises and multi-stage fracture systems confine the development range of karst reservoirs and control hydrocarbon migration, accumulation and reservoiring; (3) Long-term multi-source hydrocarbon supply, early reservoiring alteration and late charging adjustment are important reservoiring mechanisms and determine the resource structure and oil and gas properties. Favorable areas for exploration of Ordovician carbonate basement hydrocarbon reservoirs in the Tarim Basin are the Akekule rise, Katahe uplift, Hetianhe paleo-high and Yakela faulted rise.

  13. Phenomenology of tremor-like signals observed over hydrocarbon reservoirs

    NARCIS (Netherlands)

    Dangel, S.; Schaepman, M.E.; Stoll, E.P.; Carniel, R.; Barzandji, O.; Rode, E.D.; Singer, J.M.

    2003-01-01

    We have observed narrow-band, low-frequency (1.5-4 Hz, amplitude 0.01-10 mum/s) tremor signals on the surface over hydrocarbon reservoirs (oil, gas and water multiphase fluid systems in porous media) at currently 15 sites worldwide. These 'hydrocarbon tremors' possess remarkably similar spectral and

  14. Phenomenology of tremor-like signals observed over hydrocarbon reservoirs

    NARCIS (Netherlands)

    Dangel, S.; Schaepman, M.E.; Stoll, E.P.; Carniel, R.; Barzandji, O.; Rode, E.D.; Singer, J.M.

    2003-01-01

    We have observed narrow-band, low-frequency (1.5-4 Hz, amplitude 0.01-10 mum/s) tremor signals on the surface over hydrocarbon reservoirs (oil, gas and water multiphase fluid systems in porous media) at currently 15 sites worldwide. These 'hydrocarbon tremors' possess remarkably similar spectral and

  15. A preliminary evaluation model for reservoir hydrocarbon-generating potential established based on dissolved hydrocarbons in oilfield water

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A large number of oilfield water samples were analyzed in this work. Research on the relationship between the concentrations and distribution of dissolved hydrocarbons sug gested that the contents and composition of dissolved hydrocarbons varied with the hydrocar bon-generating potential of reservoirs. The concentrations of dissolved hydrocarbons were low in dry layers, water layers and gas-water layers, but high in gas reservoirs and oil reservoirs, especially in gas reservoirs with condensed oil. Series of carbon-number alkanes were usually absent in oilfield water from dry layers, water layers and gas-water layers but abundant in oil field water from oil-water reservoirs, gas reservoirs and oil reservoirs, whose carbon numbers varied most widely in oil reservoirs and least in gas reservoirs. A preliminary evaluation model for reservoir hydrocarbon-generating potential was established based on the characteristics of dissolved hydrocarbons in oilfield water to assist hydrocarbon exploration.

  16. Natural gas leakage of Mizhi gas reservoir in Ordos Basin, recorded by natural gas fluid inclusion

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Abundant natural gas inclusions were found in calcite veins filled in fractures of Central Fault Belt across the centre of Ordos Basin. Time of the calcite veins and characteristics of natural gas fluid inclusion were investigated by means of dating of thermolum luminescence (TL) and analyzing stable isotope of fluid inclusion. Results show that natural gas inclusion formed at 130―140℃ with salinity of 5.5 wt%―6.0 wt% NaCl. It indicates that natural gas inclusion is a kind of thermal hydrocarbon fluid formed within the basin. Method of opening inclusion by heating was used to analyze composition of fluid inclusion online, of which the maximal hydrocarbon gas content of fluid inclusion contained in veins is 2.4219 m3/t rock and the maximal C1/Σci ratio is 91%. Laser Raman spectroscopy (LRS) was used to analyze chemistry of individual fluid inclusion in which the maximal hydrocarbon gas content is 91.6% compared with little inorganic composition. Isotope analysis results of calcite veins show that they were deposited in fresh water, in which the δ13CPDB of calcite veins is from -5.75‰ to 15.23‰ andδ18OSMOW of calcite veins is from 21.33‰ to 21.67‰. Isotope results show thatδ13C1 PDB of natural gas fluid inclusion is from -21.36‰ to -29.06‰ and δDSMOW of that is from -70.89‰ to -111.03‰. It indicates that the gas of fluid inclusion formed from coal source rocks and it is the same as that of natural gas of Mizhi gas reservoir. Results of TL dating show that time of calcite vein is (32.4±3.42)×104 a, which is thought to be formation time of gas inclusion. It indicated that natural gas inclusion contained in calcite veins recorded natural gas leakage from Mizhi gas reservoir through the Central Fault Belt due to Himalayan tectonic movement.

  17. Data Compression of Hydrocarbon Reservoir Simulation Grids

    KAUST Repository

    Chavez, Gustavo Ivan

    2015-05-28

    A dense volumetric grid coming from an oil/gas reservoir simulation output is translated into a compact representation that supports desired features such as interactive visualization, geometric continuity, color mapping and quad representation. A set of four control curves per layer results from processing the grid data, and a complete set of these 3-dimensional surfaces represents the complete volume data and can map reservoir properties of interest to analysts. The processing results yield a representation of reservoir simulation results which has reduced data storage requirements and permits quick performance interaction between reservoir analysts and the simulation data. The degree of reservoir grid compression can be selected according to the quality required, by adjusting for different thresholds, such as approximation error and level of detail. The processions results are of potential benefit in applications such as interactive rendering, data compression, and in-situ visualization of large-scale oil/gas reservoir simulations.

  18. Direct hydrocarbon exploration and gas reservoir development technology

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Young Hoon; Oh, Jae Ho; Jeong, Tae Jin [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)] [and others

    1995-12-01

    In order to enhance the capability of petroleum exploration and development techniques, three year project (1994 - 1997) was initiated on the research of direct hydrocarbon exploration and gas reservoir development. This project consists of four sub-projects. (1) Oil(Gas) - source rock correlation technique: The overview of bio-marker parameters which are applicable to hydrocarbon exploration has been illustrated. Experimental analysis of saturated hydrocarbon and bio-markers of the Pohang E and F core samples has been carried out. (2) Study on surface geochemistry and microbiology for hydrocarbon exploration: the test results of the experimental device for extraction of dissolved gases from water show that the device can be utilized for the gas geochemistry of water. (3) Development of gas and gas condensate reservoirs: There are two types of reservoir characterization. For the reservoir formation characterization, calculation of conditional simulation was compared with that of unconditional simulation. In the reservoir fluid characterization, phase behavior calculations revealed that the component grouping is more important than the increase of number of components. (4) Numerical modeling of seismic wave propagation and full waveform inversion: Three individual sections are presented. The first one is devoted to the inversion theory in general sense. The second and the third sections deal with the frequency domain pseudo waveform inversion of seismic reflection data and refraction data respectively. (author). 180 refs., 91 figs., 60 tabs.

  19. Detection of new hydrocarbon reservoir using hydrocarbon microtremor combined attribute analysis

    Science.gov (United States)

    Ramadhan, Dimmas; Nugraha, Andri Dian; Afnimar, Akbar, Muhammad Fadhillah; Mulyanagara, Guntur

    2013-09-01

    An increasing demand for oil and gas production undoubtedly triggered innovation in exploration studies to find new hydrocarbon reservoir. Low-frequency passive seismic method named Hy MAS (Hydrocarbon Microtremor Analysis) is a new method invented and developed recently by Spectraseis which provide a quick look to find new hydrocarbon reservoir prospect area. This method based on empirical study which investigated an increasing of spectra anomaly between 2 - 4 Hz above reservoir but missing from the measurement distant from the reservoir. This method is quite promising because it has been used as another DHI (Direct Hydrocarbon Indicator) instead of active seismic survey which has some problem when applied in sensitive biomes. Another advantage is this method is completely passive and does not require seismic artificial excitation sources. In this study, by utilizing many attributes mentioned in the latest publication of this method, we try to localize new hydrocarbon prospect area outside from the proven production field. We deployed 63 stations of measurement with two of them are located above the known reservoir production site. We measured every single attribute for each data acquired from all station and mapped it spatially for better understanding and interpretation. The analysis has been made by considering noise identification from the measurement location and controlled by the attribute values from the data acquired by two stations above the reservoir. As the result, we combined each attribute analysis and mapped it in weighted-scoring map which provide the level of consistency for every single attribute calculated in each station. Finally, the new reservoir location can be suggested by the station which has a weighted-score around the values from the two production reservoir stations. We successfully identified 5 new stations which expected to have good prospect of hydrocarbon reservoir.

  20. Enhanced characterization of reservoir hydrocarbon components using electromagnetic data attributes

    KAUST Repository

    Katterbauer, Klemens

    2015-12-23

    Advances in electromagnetic imaging techniques have led to the growing utilization of this technology for reservoir monitoring and exploration. These exploit the strong conductivity contrast between the hydrocarbon and water phases and have been used for mapping water front propagation in hydrocarbon reservoirs and enhancing the characterization of the reservoir formation. The conventional approach for the integration of electromagnetic data is to invert the data for saturation properties and then subsequently use the inverted properties as constraints in the history matching process. The non-uniqueness and measurement errors may however make this electromagnetic inversion problem strongly ill-posed, leading to potentially inaccurate saturation profiles. Another limitation of this approach is the uncertainty of Archie\\'s parameters in relating rock conductivity to water saturation, which may vary in the reservoir and are generally poorly known. We present an Ensemble Kalman Filter framework for efficiently integrating electromagnetic data into the history matching process and for simultaneously estimating the Archie\\'s parameters and the variance of the observation error of the electromagnetic data. We apply the proposed framework to a compositional reservoir model. We aim at assessing the relevance of EM data for estimating the different hydrocarbon components of the reservoir. The experimental results demonstrate that the individual hydrocarbon components are generally well matched, with nitrogen exhibiting the strongest improvement. The estimated observation error standard deviations are also within expected levels (between 5 and 10%), significantly contributing to the robustness of the proposed EM history matching framework. Archie\\'s parameter estimates approximate well the reference profile and assist in the accurate description of the electrical conductivity properties of the reservoir formation, hence leading to estimation accuracy improvements of around

  1. Influence of Chemical, Mechanical, and Transport Processes on Wellbore Leakage from Geologic CO2 Storage Reservoirs.

    Science.gov (United States)

    Carroll, Susan A; Iyer, Jaisree; Walsh, Stuart D C

    2017-08-15

    Wells are considered to be high-risk pathways for fluid leakage from geologic CO2 storage reservoirs, because breaches in this engineered system have the potential to connect the reservoir to groundwater resources and the atmosphere. Given these concerns, a few studies have assessed leakage risk by evaluating regulatory records, often self-reported, documenting leakage in gas fields. Leakage is thought to be governed largely by initial well-construction quality and the method of well abandonment. The geologic carbon storage community has raised further concerns because acidic fluids in the CO2 storage reservoir, alkaline cement meant to isolate the reservoir fluids from the overlying strata, and steel casings in wells are inherently reactive systems. This is of particular concern for storage of CO2 in depleted oil and gas reservoirs with numerous legacy wells engineered to variable standards. Research suggests that leakage risks are not as great as initially perceived because chemical and mechanical alteration of cement has the capacity to seal damaged zones. Our work centers on defining the coupled chemical and mechanical processes governing flow in damaged zones in wells. We have developed process-based models, constrained by experiments, to better understand and forecast leakage risk. Leakage pathways can be sealed by precipitation of carbonate minerals in the fractures and deformation of the reacted cement. High reactivity of cement hydroxides releases excess calcium that can precipitate as carbonate solids in the fracture network under low brine flow rates. If the flow is fast, then the brine remains undersaturated with respect to the solubility of calcium carbonate minerals, and zones depleted in calcium hydroxides, enriched in calcium carbonate precipitates, and made of amorphous silicates leached of original cement minerals are formed. Under confining pressure, the reacted cement is compressed, which reduces permeability and lowers leakage risks. The

  2. Water leakage investigation of micro-dam reservoirs in Mesozoic sedimentary sequences in Northern Ethiopia

    Science.gov (United States)

    Berhane, Gebremedhin; Martens, Kristine; Al Farrah, Nawal; Walraevens, Kristine

    2013-03-01

    Millions of people throughout the world depend on dam reservoirs for domestic water supply, irrigation, electricity and flood protection. In the last two decades, 54 micro-dam reservoirs have been constructed in Northern Ethiopia to fight the recurrent drought and improve agricultural productivity through irrigation. However, about 60% of these micro-dam reservoirs are suffering from excessive leakage. Comprehensive studies have been carried out on two micro-dams to assess and pinpoint the causes of leakage. Arato and Hashenge micro-dams located in Northern Ethiopia have 20 m and 19 m height, and 2.59 Mm3 and 2.23 Mm3 reservoir capacities respectively. Observational geological description, shallow hand dug test pits, vertical electrical sounding and drilling of geotechnical holes were used to understand the overall geological, engineering geological and geo-hydrological set-up of the area. The different methods applied, such as discontinuity analysis, geophysical surveys, drilling and packer tests, delivered results that were found to be in close agreement and led to the identification of the leakage zone. The geological units found in both sites are limestone-shale-marl intercalation, dolerite and recent soil deposits. The research results revealed that the limestone-shale-marl intercalation unit is heterogeneous and shows alternating sequences. Analysis of the different data shows that the limestone-shale-marl intercalation is a pervious unit (hydraulic conductivity in the range of 10-4-10+2 cm/s) and was found to be responsible for the excessive leakage of the micro-dams. It is hoped that the observations, data and insights gathered from these case studies will enable to plan technically and economically viable anti-leakage measures for these schemes and help for future new site selection and design activities in the region and other regions with a similar geological environment.

  3. Key Factors for Determining Risk of Groundwater Impacts Due to Leakage from Geologic Carbon Sequestration Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Carroll, Susan [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Keating, Elizabeth [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mansoor, Kayyum [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dai, Zhenue [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Sun, Yunwei [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Trainor-Guitton, Whitney [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brown, Chris [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bacon, Diana [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2014-01-06

    The National Risk Assessment Partnership (NRAP) is developing a science-based toolset for the analysis of potential impacts to groundwater chemistry from CO2 injection (www.netldoe.gov/nrap). The toolset adopts a stochastic approach in which predictions address uncertainties in shallow underwater and leakage scenarios. It is derived from detailed physics and chemistry simulation results that are used to train more computationally efficient models,l referred to here as reduced-order models (ROMs), for each component system. In particular, these tools can be used to help regulators and operators understand the expected sizes and longevity of plumes in pH, TDS, and dissolved metals that could result from a leakage of brine and/or CO2 from a storage reservoir into aquifers. This information can inform, for example, decisions on monitoring strategies that are both effective and efficient. We have used this approach to develop predictive reduced-order models for two common types of reservoirs, but the approach could be used to develop a model for a specific aquifer or other common types of aquifers. In this paper we describe potential impacts to groundwater quality due to CO2 and brine leakage, discuss an approach to calculate thresholds under which "no impact" to groundwater occurs, describe the time scale for impact on groundwater, and discuss the probability of detecting a groundwater plume should leakage occur.

  4. The Stimulation of Hydrocarbon Reservoirs with Subsurface Nuclear Explosions

    Energy Technology Data Exchange (ETDEWEB)

    LORENZ,JOHN C.

    2000-12-08

    Between 1965 and 1979 there were five documented and one or more inferred attempts to stimulate the production from hydrocarbon reservoirs by detonating nuclear devices in reservoir strata. Of the five documented tests, three were carried out by the US in low-permeability, natural-gas bearing, sandstone-shale formations, and two were done in the USSR within oil-bearing carbonates. The objectives of the US stimulation efforts were to increase porosity and permeability in a reservoir around a specific well by creating a chimney of rock rubble with fractures extending beyond it, and to connect superimposed reservoir layers. In the USSR, the intent was to extensively fracture an existing reservoir in the more general vicinity of producing wells, again increasing overall permeability and porosity. In both countries, the ultimate goals were to increase production rates and ultimate recovery from the reservoirs. Subsurface explosive devices ranging from 2.3 to about 100 kilotons were used at depths ranging from 1208 m (3963 ft) to 2568 m (8427 ft). Post-shot problems were encountered, including smaller-than-calculated fracture zones, formation damage, radioactivity of the product, and dilution of the BTU value of tie natural gas with inflammable gases created by the explosion. Reports also suggest that production-enhancement factors from these tests fell short of expectations. Ultimately, the enhanced-production benefits of the tests were insufficient to support continuation of the pro-grams within increasingly adversarial political, economic, and social climates, and attempts to stimulate hydrocarbon reservoirs with nuclear devices have been terminated in both countries.

  5. Geofluid dynamic concept of hydrocarbon accumulation in natural reservoirs

    Science.gov (United States)

    Kerimov, V. Yu.; Rachinsky, M. Z.

    2016-11-01

    Most modern theories axiomatically assume that hydrocarbons (HCs), which migrate in different ways from the generation zones and sources with high gradients of reduced pressures, concentrate in autochthonous natural reservoirs possessing smaller levels of reservoir energy. Hydraulic drainage of reservoirs is possible in principle through only three mechanisms: (i) horizontally oriented regional elisional water flow upwards, along the plunge of general folding from central parts of basins towards their peripheral frames; (ii) owing to the effect of lateral pressure of groundwater immediately in traps, with subsequent pushing out by high-pressure fluids supplied to the sunken parts of folds; (iii) vertically directed, from bottom to top, overflow injection mechanism. The study of their possible implementations and relative ratios in the outcome comprise the content of the proposed fluid-dynamic concept of HC accumulation.

  6. Seismic Evaluation of Hydrocarbon Saturation in Deep-Water Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Michael Batzle

    2006-04-30

    During this last period of the ''Seismic Evaluation of Hydrocarbon Saturation in Deep-Water Reservoirs'' project (Grant/Cooperative Agreement DE-FC26-02NT15342), we finalized integration of rock physics, well log analysis, seismic processing, and forward modeling techniques. Most of the last quarter was spent combining the results from the principal investigators and come to some final conclusions about the project. Also much of the effort was directed towards technology transfer through the Direct Hydrocarbon Indicators mini-symposium at UH and through publications. As a result we have: (1) Tested a new method to directly invert reservoir properties, water saturation, Sw, and porosity from seismic AVO attributes; (2) Constrained the seismic response based on fluid and rock property correlations; (3) Reprocessed seismic data from Ursa field; (4) Compared thin layer property distributions and averaging on AVO response; (5) Related pressures and sorting effects on porosity and their influence on DHI's; (6) Examined and compared gas saturation effects for deep and shallow reservoirs; (7) Performed forward modeling using geobodies from deepwater outcrops; (8) Documented velocities for deepwater sediments; (9) Continued incorporating outcrop descriptive models in seismic forward models; (10) Held an open DHI symposium to present the final results of the project; (11) Relations between Sw, porosity, and AVO attributes; (12) Models of Complex, Layered Reservoirs; and (14) Technology transfer Several factors can contribute to limit our ability to extract accurate hydrocarbon saturations in deep water environments. Rock and fluid properties are one factor, since, for example, hydrocarbon properties will be considerably different with great depths (high pressure) when compared to shallow properties. Significant over pressure, on the other hand will make the rocks behave as if they were shallower. In addition to the physical properties, the scale and

  7. Noble gas and hydrocarbon tracers in multiphase unconventional hydrocarbon systems: Toward integrated advanced reservoir simulators

    Science.gov (United States)

    Darrah, T.; Moortgat, J.; Poreda, R. J.; Muehlenbachs, K.; Whyte, C. J.

    2015-12-01

    Although hydrocarbon production from unconventional energy resources has increased dramatically in the last decade, total unconventional oil and gas recovery from black shales is still less than 25% and 9% of the totals in place, respectively. Further, the majority of increased hydrocarbon production results from increasing the lengths of laterals, the number of hydraulic fracturing stages, and the volume of consumptive water usage. These strategies all reduce the economic efficiency of hydrocarbon extraction. The poor recovery statistics result from an insufficient understanding of some of the key physical processes in complex, organic-rich, low porosity formations (e.g., phase behavior, fluid-rock interactions, and flow mechanisms at nano-scale confinement and the role of natural fractures and faults as conduits for flow). Noble gases and other hydrocarbon tracers are capably of recording subsurface fluid-rock interactions on a variety of geological scales (micro-, meso-, to macro-scale) and provide analogs for the movement of hydrocarbons in the subsurface. As such geochemical data enrich the input for the numerical modeling of multi-phase (e.g., oil, gas, and brine) fluid flow in highly heterogeneous, low permeability formations Herein we will present a combination of noble gas (He, Ne, Ar, Kr, and Xe abundances and isotope ratios) and molecular and isotopic hydrocarbon data from a geographically and geologically diverse set of unconventional hydrocarbon reservoirs in North America. Specifically, we will include data from the Marcellus, Utica, Barnett, Eagle Ford, formations and the Illinois basin. Our presentation will include geochemical and geological interpretation and our perspective on the first steps toward building an advanced reservoir simulator for tracer transport in multicomponent multiphase compositional flow (presented separately, in Moortgat et al., 2015).

  8. Prediction of Hydrocarbon Reservoirs Permeability Using Support Vector Machine

    Directory of Open Access Journals (Sweden)

    R. Gholami

    2012-01-01

    Full Text Available Permeability is a key parameter associated with the characterization of any hydrocarbon reservoir. In fact, it is not possible to have accurate solutions to many petroleum engineering problems without having accurate permeability value. The conventional methods for permeability determination are core analysis and well test techniques. These methods are very expensive and time consuming. Therefore, attempts have usually been carried out to use artificial neural network for identification of the relationship between the well log data and core permeability. In this way, recent works on artificial intelligence techniques have led to introduce a robust machine learning methodology called support vector machine. This paper aims to utilize the SVM for predicting the permeability of three gas wells in the Southern Pars field. Obtained results of SVM showed that the correlation coefficient between core and predicted permeability is 0.97 for testing dataset. Comparing the result of SVM with that of a general regression neural network (GRNN revealed that the SVM approach is faster and more accurate than the GRNN in prediction of hydrocarbon reservoirs permeability.

  9. Main controlling factors for hydrocarbon reservoir formation and petroleum distribution in Cratonic Area of Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The Cratonic Area of the Tarim Basin is located in the central part of the basin, developing primarily with Cambrian marine source rocks and secondly Middle to Upper Ordovician marine and Carboniferous-Permian transitional facies source rocks. The source rocks were matured in the changeable period and space, forming multiple hydrocarbon generating centers during the periods. The Cratonic Area experienced multiple tectonic orogenies, forming several palaeouplifts. The matching condition between effective hydrocarbon generating centers and the palaeouplifts in various periods is the main control factor for the formation and distribution of hydrocarbon reservoirs. The palaeouplifts have experienced multiple hydrocarbon-filling phases, several periods of modifications and even breakdown. The palaeouplifts and the adjacent slopes around the effective hydrocarbon generating center compose the most favorable places for hydrocarbon accumulation. The hydrocarbon phase is related with the evolution of the hydrocarbon generating center. In the Tarim Basin's Cratonic Area, reservoirs were mostly formed during late Hercynian. The originally formed hydrocarbon reservoirs which are adjacent to source kitchens and in the good preservation condition are the most favorable prospecting targets. Hydrocarbon is richly accumulated under the regional caprock, surrounding the faulted trends, and over and below the unconformity surfaces. Reservoirs in the Carboniferous sandstone, Ordovician karstic weathered crust and carbonate rock inside the buried hill compose the main intervals for hydrocarbon accumulation. Carboniferous and Silurian sandstone pinchout reservoirs and carbonate lithologic reservoirs with rich fractures and pores are the main targets for further prospecting.

  10. SEISMIC EVALUATION OF HYDROCARBON SATURATION IN DEEP-WATER RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    M. Batzle; D-h Han; R. Gibson; O. Djordjevic

    2003-03-20

    The ''Seismic Evaluation of Hydrocarbon Saturation in Deep-Water Reservoirs'' (Grant/Cooperative Agreement DE-FC26-02NT15342) began September 1, 2002. During this second quarter: A Direct Hydrocarbon Indicator (DHI) symposium was held at UH; Current DHI methods were presented and forecasts made on future techniques; Dr. Han moved his laboratory from HARC to the University of Houston; Subcontracts were re-initiated with UH and TAMU; Theoretical and numerical modeling work began at TAMU; Geophysical Development Corp. agreed to provide petrophysical data; Negotiations were begun with Veritas GDC to obtain limited seismic data; Software licensing and training schedules were arranged with Paradigm; and Data selection and acquisition continues. The broad industry symposium on Direct Hydrocarbon Indicators was held at the University of Houston as part of this project. This meeting was well attended and well received. A large amount of information was presented, not only on application of the current state of the art, but also on expected future trends. Although acquisition of appropriate seismic data was expected to be a significant problem, progress has been made. A 3-D seismic data set from the shelf has been installed at Texas A&M University and analysis begun. Veritas GDC has expressed a willingness to provide data in the deep Gulf of Mexico. Data may also be available from TGS.

  11. Hydrocarbons Emissions Due to Wellbore and other Subsurface Leakage in the Uintah Basin, Utah

    Science.gov (United States)

    Watkins, C.; Lyman, S. N.

    2015-12-01

    The explosive growth of oil and gas production in the United States has focused public and regulatory attention on environmental impacts of hydrocarbon extraction, including air quality and climate impacts. One potentially important emissions source is subsurface leakage of natural gas. Better understanding of wellbore and other subsurface leaks are important in providing ways to decrease pollution while increasing the efficiency of oil and gas production. Soil gas measurements carried out by USGS over the last several years in Utah's oil and gas fields have shown that, while concentrations of methane in soils near wells are typically low, soil gas near some wells can contain more than 50% methane. In the summers of 2013-2015 we carried out campaigns to measure the emission rate of methane and other hydrocarbons from soils near wells in the Uintah Basin, Utah. We also measured emissions at several locations on individual well pads and determined that concentrations of hydrocarbons tend to decrease with distance from the well head. Soil emissions were also measured at non-well sites in the same area to determine background emission rates. Emissions from exposed coal, oil shale, gilsonite, and fault zone surfaces were also measured. Relationships of emissions with soil gas concentrations, meteorological conditions, and soil properties were also investigated.

  12. Reduced-Order Model for Leakage Through an Open Wellbore from the Reservoir due to Carbon Dioxide Injection

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Lehua [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Oldenburg, Curtis M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-07-26

    Potential CO2 leakage through existing open wellbores is one of the most significant hazards that need to be addressed in geologic carbon sequestration (GCS) projects. In the framework of the National Risk Assessment Partnership (NRAP) which requires fast computations for uncertainty analysis, rigorous simulation of the coupled wellbore-reservoir system is not practical. We have developed a 7,200-point look-up table reduced-order model (ROM) for estimating the potential leakage rate up open wellbores in response to CO2 injection nearby. The ROM is based on coupled simulations using T2Well/ECO2H which was run repeatedly for representative conditions relevant to NRAP to create a look-up table response-surface ROM. The ROM applies to a wellbore that fully penetrates a 20-m thick reservoir that is used for CO2 storage. The radially symmetric reservoir is assumed to have initially uniform pressure, temperature, gas saturation, and brine salinity, and it is assumed these conditions are held constant at the far-field boundary (100 m away from the wellbore). In such a system, the leakage can quickly reach quasi-steady state. The ROM table can be used to estimate both the free-phase CO2 and brine leakage rates through an open well as a function of wellbore and reservoir conditions. Results show that injection-induced pressure and reservoir gas saturation play important roles in controlling leakage. Caution must be used in the application of this ROM because well leakage is formally transient and the ROM lookup table was populated using quasi-steady simulation output after 1000 time steps which may correspond to different physical times for the various parameter combinations of the coupled wellbore-reservoir system.

  13. On CO2 Behavior in the Subsurface, Following Leakage from aGeologic Storage Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, Karsten

    2006-02-09

    The amounts of CO2 that would need to be injected intogeologic storage reservoirs to achieve a significant reduction ofatmospheric emissions are very large. A 1000 MWe coal-fired power plantemits approximately 30,000 tonnes of CO2 per day, 10 Mt per year(Hitchon, 1996). When injected underground over a typical lifetime of 30years of such a plant, the CO2 plume may occupy a large area of order 100km2 or more, and fluid pressure increase in excess of 1 bar(corresponding to 10 m water head) may extend over an area of more than2,500 km2 (Pruess, et al., 2003). The large areal extent expected for CO2plumes makes it likely that caprock imperfections will be encountered,such as fault zones or fractures, which may allow some CO2 to escape fromthe primary storage reservoir. Under most subsurface conditions oftemperature and pressure, CO2 is buoyant relative to groundwaters. If(sub-)vertical pathways are available, CO2 will tend to flow upward and,depending on geologic conditions, may eventually reach potablegroundwater aquifers or even the land surface. Leakage of CO2 could alsooccur along wellbores, including pre-existing and improperly abandonedwells, or wells drilled in connection with the CO2 storage operations.The pressure increases accompanying CO2 injection will give rise tochanges in effective stress that could cause movement along faults,increasing permeability and potential for leakage.Escape of CO2 from aprimary geologic storage reservoir and potential hazards associated withits discharge at the land surface raise a number of concerns, including(1) acidification of groundwater resources, (2) asphyxiation hazard whenleaking CO2 is discharged at the land surface, (3) increase inatmospheric concentrations of CO2, and (4) damage from a high-energy,eruptive discharge (if such discharge is physically possible). In orderto gain public acceptance for geologic storage as a viable technology forreducing atmospheric emissions of CO2, it is necessary to address theseissues

  14. Accounting for geochemical alterations of caprock fracture permeability in basin-scale models of leakage from geologic CO2 reservoirs

    Science.gov (United States)

    Guo, B.; Fitts, J. P.; Dobossy, M.; Bielicki, J. M.; Peters, C. A.

    2012-12-01

    Climate mitigation, public acceptance and energy, markets demand that the potential CO2 leakage rates from geologic storage reservoirs are predicted to be low and are known to a high level of certainty. Current approaches to predict CO2 leakage rates assume constant permeability of leakage pathways (e.g., wellbores, faults, fractures). A reactive transport model was developed to account for geochemical alterations that result in permeability evolution of leakage pathways. The one-dimensional reactive transport model was coupled with the basin-scale Estimating Leakage Semi-Analytical (ELSA) model to simulate CO2 and brine leakage through vertical caprock pathways for different CO2 storage reservoir sites and injection scenarios within the Mt. Simon and St. Peter sandstone formations of the Michigan basin. Mineral dissolution in the numerical reactive transport model expands leakage pathways and increases permeability as a result of calcite dissolution by reactions driven by CO2-acidified brine. A geochemical model compared kinetic and equilibrium treatments of calcite dissolution within each grid block for each time step. For a single fracture, we investigated the effect of the reactions on leakage by performing sensitivity analyses of fracture geometry, CO2 concentration, calcite abundance, initial permeability, and pressure gradient. Assuming that calcite dissolution reaches equilibrium at each time step produces unrealistic scenarios of buffering and permeability evolution within fractures. Therefore, the reactive transport model with a kinetic treatment of calcite dissolution was coupled to the ELSA model and used to compare brine and CO2 leakage rates at a variety of potential geologic storage sites within the Michigan basin. The results are used to construct maps based on the susceptibility to geochemically driven increases in leakage rates. These maps should provide useful and easily communicated inputs into decision-making processes for siting geologic CO2

  15. USGS investigations of water produced during hydrocarbon reservoir development

    Science.gov (United States)

    Engle, Mark A.; Cozzarelli, Isabelle M.; Smith, Bruce D.

    2014-01-01

    Significant quantities of water are present in hydrocarbon reservoirs. When brought to the land surface during oil, gas, and coalbed methane production, the water—either naturally occurring or injected as a method to enhance production—is termed produced water. Produced water is currently managed through processes such as recycling, treatment and discharge, spreading on roads, evaporation or infiltration, and deep well injection. U.S. Geological Survey (USGS) scientists conduct research and publish data related to produced water, thus providing information and insight to scientists, decisionmakers, the energy industry, and the public. The information advances scientific knowledge, informs resource management decisions, and facilitates environmental protection. This fact sheet discusses integrated research being conducted by USGS scientists supported by programs in the Energy and Minerals and Environmental Health Mission Areas. The research products help inform decisions pertaining to understanding the nature and management of produced water in the United States.

  16. On the water saturation calculation in hydrocarbon sandstone reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Stalheim, Stein Ottar

    2002-07-01

    The main goal of this work was to identify the most important uncertainty sources in water saturation calculation and examine the possibility for developing new S{sub w} - equations or possibility to develop methods to remove weaknesses and uncertainties in existing S{sub w} - equations. Due to the need for industrial applicability of the equations we aimed for results with the following properties: The accuracy in S{sub w} should increase compared with existing S{sub w} - equations. The equations should be simple to use in petrophysical evaluations. The equations should be based on conventional logs and use as few as possible input parameters. The equations should be numerical stable. This thesis includes an uncertainty and sensitivity analysis of the most common S{sub w} equations. The results are addressed in chapter 3 and were intended to find the most important uncertainty sources in water saturation calculation. To increase the knowledge of the relationship between R{sub t} and S{sub w} in hydrocarbon sandstone reservoirs and to understand how the pore geometry affects the conductivity (n and m) of the rock a theoretical study was done. It was also an aim to examine the possibility for developing new S{sub w} - equations (or investigation an effective medium model) valid inhydrocarbon sandstone reservoirs. The results are presented in paper 1. A new equation for water saturation calculation in clean sandstone oil reservoirs is addressed in paper 2. A recommendation for best practice of water saturation calculation in non water wet formation is addressed in paper 3. Finally a new equation for water saturation calculation in thinly interbedded sandstone/mudstone reservoirs is presented in paper 4. The papers are titled: 1) Is the saturation exponent n a constant. 2) A New Model for Calculating Water Saturation In 3) Influence of wettability on water saturation modeling. 4) Water Saturation Calculations in Thinly Interbedded Sandstone/mudstone Reservoirs. A

  17. Alteration and Reformation of Hydrocarbon Reservoirs and Prediction of Remaining Potential Resources in Superimposed Basins

    Institute of Scientific and Technical Information of China (English)

    PANG Hong; PANG Xiongqi; YANG Haijun; LIN Changsong; MENG Qingyang; WANG Huaijie

    2010-01-01

    Complex hydrocarbon reservoirs developed widely in the superimposed basins of China formed from multiple structural alterations,reformation and destruction of hydrocarbon reservoirs formed at early stages.They are characterized currently by trap adjustment,component variation,phase conversion,and scale reformation.This is significant for guiding current hydrocarbon exploration by revealing evolution mechanisms after hydrocarbon reservoir formation and for predicting remaining potential resources.Based on the analysis of a number of complex hydrocarbon reservoirs,there are four geologic features controlling the degree of destruction of hydrocarbon reservoirs formed at early stages:tectonic event intensity,frequency,time and caprock sealing for oil and gas during tectonic evolution.Research shows that the larger the tectonic event intensity,the more frequent the tectonic event,the later the last tectonic event,the weaker the caprock sealing for oil and gas,and the greater the volume of destroyed hydrocarbons in the early stages.Based on research on the main controlling factors of hydrocarbon reservoir destruction mechanisms,a geological model of tectonic superimposition and a mathematical model evaluating potential remaining complex hydrocarbon reservoirs have been established.The predication method and technical procedures were applied in the Tazhong area of Tarim Basin,where four stages of hydrocarbon accumulation and three stages of hydrocarbon alteration occurred.Geohistorical hydrocarbon accumulation reached 3.184billion tons,of which 1.271 billion tons were destroyed.The total volume of remaining resources available for exploration is~1.9 billion tons.

  18. Hydrocarbon charge history of the Paleogene reservoir in the northern Dongpu Depression, Bohai Bay Basin, China

    Directory of Open Access Journals (Sweden)

    You-Lu Jiang

    2016-11-01

    Full Text Available Abstract The hydrocarbon charge history of the Paleogene in the northern Dongpu Depression was analyzed in detail based on a comprehensive analysis of the generation and expulsion history of the major hydrocarbon source rocks, fluorescence microscopic features and fluid inclusion petrography. There were two main stages of hydrocarbon generation and expulsion of oil from the major hydrocarbon source rocks. The first stage was the main hydrocarbon expulsion stage. The fluorescence microscopic features also indicated two stages of hydrocarbon accumulation. Carbonaceous bitumen, asphaltene bitumen and colloidal bitumen reflected an early hydrocarbon charge, whereas the oil bitumen reflected a second hydrocarbon charge. Hydrocarbon inclusions also indicate two distinct charges according to the diagenetic evolution sequence, inclusion petrography features combined with the homogenization temperature and reservoir burial history analysis. According to these comprehensive analysis results, the hydrocarbon charge history of the Paleogene reservoir in the northern Dongpu Depression was divided into two phases. The first phase was from the late Dongying depositional period of the Oligocene to the early uplift stages of the late Paleogene. The second phase was from the late Minghuazhen period of the Pliocene to the Quaternary. Reservoirs formed during the first period were widely distributed covering the entire area. In contrast, reservoirs formed during the second period were mainly distributed near the hydrocarbon generation sags. Vertically, it was characterized by a single phase in the upper layers and two phases in the lower layers of the Paleogene.

  19. Evaluating the impacts of caprock and reservoir properties on potential risk of CO2 leakage after injection

    Science.gov (United States)

    Hou, Z.; Murray, C. J.; Rockhold, M. L.

    2010-12-01

    Numerical models are essential tools for CO2 sequestration projects and should be included in the life cycle of a project. Common practice involves modeling the behavior of CO2 during and after injection using site-specific reservoir and caprock properties. Little has been done to systematically evaluate and compare the effects of a realistic range of reservoir and caprock properties on potential CO2 leakage through caprock. Broad-based research addressing the impacts of caprock properties and their heterogeneity on seal permeation is absent. Efforts along this direction require obtaining information about the physically reasonable range of caprock and reservoir properties, effectively sampling the parameter space to fully explore the range of these properties, and performing flow and transport calculations using reliable numerical simulators. In this study, we identify the most important factors affecting CO2 leakage through intact caprock and try to understand the underlying mechanisms. We use caprock and reservoir properties from various field sites and literature data to identify the range of caprock thickness, permeability, and porosity that might occur. We use a quasi Monte Carlo sampling approach to ensure that the full range of caprock and seal properties is evaluated without introducing bias. For each set of sampled properties, the migration of injected CO2 is simulated for up to 200 years using the water-salt-CO2 operational mode of the STOMP simulator, developed by PNNL. Preliminary results show that critical factors determining CO2 leakage rate through intact caprock are, in decreasing order of significance, the caprock thickness, caprock permeability, reservoir permeability, reservoir porosity, and caprock porosity. This study provides a relatively complete “look-up table” for potential CO2 leakage risk due to permeation of intact caprock, and identifies a range of acceptable seal thicknesses and permeability for sequestration projects. This

  20. Solid hydrocarbon: a migration-of-fines problem in carbonate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Lomando, A.J.

    1986-05-01

    The most familiar example of a migration-of-fines problem is authigenic kaolinite, which can detach, migrate through a pore system, and bridge pore throats, thus reducing permeability. under certain conditions, a similar problem is caused by solid hydrocarbon, independent of a mode of origin, which has precipitated in carbonate pore systems. Cores from several reservoirs in the Lower Cretaceous of east Texas were used as the data base in this study. Three morphotypes of solid hydrocarbon have been identified from thin-section and scanning electron microscope observations: droplets, peanut brittle, and carpets. Droplets are small, individual, rounded particles scattered on pore walls. Peanut brittle ranges from a continuous to discontinuous thin coating with random rounded lumps that probably have droplet precursors. Carpets are thick, continuous coatings and, at the extreme, can effectively occlude whole pores. Initially, solid hydrocarbon reduces permeability without necessarily decreasing porosity significantly. Likewise, solid hydrocarbon cannot be detected directly from wireline logs. Acidizing to enhance communication to the well bore is a common completion procedure in limestone and calcareous sandstone reservoirs. In reservoirs containing solid hydrocarbon, acid etches the substrate and releases solid hydrocarbon, which migrates in the pore system and bridges pore throats. Differential well-bore pressure also may cause solid hydrocarbon to migrate. Therefore, wettability, which controls hydrocarbon adhesion to the pore walls, and the dominant morphotype are important factors in the extent of reservoir damage.

  1. Calculation of hydrocarbon-in-place in gas and gas-condensate reservoirs - Carbon dioxide sequestration

    Science.gov (United States)

    Verma, Mahendra K.

    2012-01-01

    The Energy Independence and Security Act of 2007 (Public Law 110-140) authorized the U.S. Geological Survey (USGS) to conduct a national assessment of geologic storage resources for carbon dioxide (CO2), requiring estimation of hydrocarbon-in-place volumes and formation volume factors for all the oil, gas, and gas-condensate reservoirs within the U.S. sedimentary basins. The procedures to calculate in-place volumes for oil and gas reservoirs have already been presented by Verma and Bird (2005) to help with the USGS assessment of the undiscovered resources in the National Petroleum Reserve, Alaska, but there is no straightforward procedure available for calculating in-place volumes for gas-condensate reservoirs for the carbon sequestration project. The objective of the present study is to propose a simple procedure for calculating the hydrocarbon-in-place volume of a condensate reservoir to help estimate the hydrocarbon pore volume for potential CO2 sequestration.

  2. Hydrocarbon accumulation characteristics and enrichment laws of multi-layered reservoirs in the Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Guang Yang

    2017-03-01

    Full Text Available The Sichuan Basin represents the earliest area where natural gas is explored, developed and comprehensively utilized in China. After over 50 years of oil and gas exploration, oil and gas reservoirs have been discovered in 24 gas-dominant layers in this basin. For the purpose of predicting natural gas exploration direction and target of each layer in the Sichuan Basin, the sedimentary characteristics of marine and continental strata in this basin were summarized and the forms of multi-cycled tectonic movement and their controlling effect on sedimentation, diagenesis and hydrocarbon accumulation were analyzed. Based on the analysis, the following characteristics were identified. First, the Sichuan Basin has experienced the transformation from marine sedimentation to continental sedimentation since the Sinian with the former being dominant. Second, multiple source–reservoir assemblages are formed based on multi-rhythmed deposition, and multi-layered reservoir hydrocarbon accumulation characteristics are vertically presented. And third, multi-cycled tectonic movement appears in many forms and has a significant controlling effect on sedimentation, diagenesis and hydrocarbon accumulation. Then, oil and gas reservoir characteristics and enrichment laws were investigated. It is indicated that the Sichuan Basin is characterized by coexistence of conventional and unconventional oil and gas reservoirs, multi-layered reservoir hydrocarbon supply, multiple reservoir types, multiple trap types, multi-staged hydrocarbon accumulation and multiple hydrocarbon accumulation models. Besides, its natural gas enrichment is affected by hydrocarbon source intensity, large paleo-uplift, favorable sedimentary facies belt, sedimentary–structural discontinuity plane and structural fracture development. Finally, the natural gas exploration and research targets of each layer in the Sichuan Basin were predicted according to the basic petroleum geologic conditions

  3. Abiogenic formation of alkanes in the Earth's crust as a minor source for global hydrocarbon reservoirs

    Science.gov (United States)

    Sherwood Lollar, B.; Westgate, T. D.; Ward, J. A.; Slater, G. F.; Lacrampe-Couloume, G.

    2002-04-01

    Natural hydrocarbons are largely formed by the thermal decomposition of organic matter (thermogenesis) or by microbial processes (bacteriogenesis). But the discovery of methane at an East Pacific Rise hydrothermal vent and in other crustal fluids supports the occurrence of an abiogenic source of hydrocarbons. These abiogenic hydrocarbons are generally formed by the reduction of carbon dioxide, a process which is thought to occur during magma cooling and-more commonly-in hydrothermal systems during water-rock interactions, for example involving Fischer-Tropsch reactions and the serpentinization of ultramafic rocks. Suggestions that abiogenic hydrocarbons make a significant contribution to economic hydrocarbon reservoirs have been difficult to resolve, in part owing to uncertainty in the carbon isotopic signatures for abiogenic versus thermogenic hydrocarbons. Here, using carbon and hydrogen isotope analyses of abiogenic methane and higher hydrocarbons in crystalline rocks of the Canadian shield, we show a clear distinction between abiogenic and thermogenic hydrocarbons. The progressive isotopic trends for the series of C1-C4 alkanes indicate that hydrocarbon formation occurs by way of polymerization of methane precursors. Given that these trends are not observed in the isotopic signatures of economic gas reservoirs, we can now rule out the presence of a globally significant abiogenic source of hydrocarbons.

  4. Impact of rock salt creep law choice on subsidence calculations for hydrocarbon reservoirs overlain by evaporite caprocks

    NARCIS (Netherlands)

    Marketos, G.; Spiers, C.J.; Govers, R.

    2016-01-01

    Accurate forward modeling of surface subsidence above producing hydrocarbons reservoirs requires an understanding of the mechanisms determining how ground deformation and subsidence evolve. Here we focus entirely on rock salt, which overlies a large number of reservoirs worldwide, and specifically

  5. Geological and geophysical investigation of water leakage from two micro-dam reservoirs: Implications for future site selection, northern Ethiopia

    Science.gov (United States)

    Berhane, Gebremedhin; Amare, Mogos; Gebreyohannes, Tesfamichael; Walraevens, Kristine

    2017-05-01

    Water resources are essential to human development activities and to eradicate extreme poverty and hunger. Geological problems of two water harvesting Micro-Dam Reservoirs (MDRs) were evaluated from leakage perspectives in the northern part of Ethiopia, East Africa. Conventional geological mapping, discontinuity and weathering descriptions, test pits and geophysical methods were used to characterize the hydrogeological features of the MDRs. Vertical Electrical Sounding (VES) and Electrical Profiling (EP), were executed using Terrameter SAS (signal averaging system) 1000 manufactured by ABEM, Sweden, with Schlumberger and Wenner array configuration respectively. It was concluded that the foundations of both MDRs, except the right abutment for Adishuhu which is partly composed of dolerite, are pervious due to the presence of thin bedding planes, joints, weathered materials and fault. The presence of water in the downstream toe of the MDRs, at depressions, existing test pits and test pits excavated during the present study which lie within the seepage zone demarcated during surface geological mapping, correspond with the electrical resistivity study. The results of the electrical resistivity survey (EP and VES) were merged with the geological and structural mapping and the observation of seepage zones, for the delineation of weak zones responsible for leakage. Monitoring of the leakage (reservoir water and groundwater levels), both manually and using automatic divers, is recommended, along with monitoring of the stability of the embankments and the discharge or flow downstream of the MDRs.

  6. Hydrocarbon charging histories of the Ordovician reservoir in the Tahe oil field, Tarim Basin, China

    Institute of Scientific and Technical Information of China (English)

    李纯泉; 陈红汉; 李思田; 张希明; 陈汉林

    2004-01-01

    The Ordovician reservoir of the Tahe oil field went through many tectonic reconstructions, and was characterized by multiple hydrocarbon chargings. The aim of this study was to unravel the complex charging histories. Systematic analysis of fluid inclusions was employed to complete the investigation. Fluorescence observation of oil inclusions under UV light, and microthermometry of both oil and aqueous inclusions in 105 core samples taken from the Ordovician reservoir indicated that the Ordovician reservoir underwent four oil chargings and a gas charging. The hydrocarbon chargings occurred at the late Hercynian, the Indo-Sinian and Yanshan, the early Himalaya, the middle Himalaya, and the late Himalaya,respectively. The critical hydrocarbon charging time was at the late Hercynian.

  7. Geoelectrical characterization of a site with hydrocarbon contamination caused by pipeline leakage

    Energy Technology Data Exchange (ETDEWEB)

    Delgado-Rodriguez, Omar; Shevnin, Vladimir; Ochoa-Valdes, Jesus [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico); Ryjov, Albert [Moscow State Geological Prospecting Academy, Moscow (Russian Federation)

    2006-01-15

    Vertical Electrical Sounding (VES) method is used extensively in environmental impact studies including hydrocarbon contamination. In this work, the results of the geoelectrical characterization of a contaminated site caused by pipeline leakage are presented. Geoelectrical study was performed with multi-electrode technology and 2D profile data interpretation. VES results from six parallel profiles were presented in resistivity sections and maps. Layered model of the site was found including aquifer and aquitard layers. Although the contamination grade of the site is low, we found two contaminated zones into sandy aquifer. Aquifer and aquitard were characterized by its resistivity, clay content, porosity and cation exchange capacity values. Recalculation of resistivity data into petrophysical sections and maps was performed by an inversion algorithm taking into account pore water salinity. Petrophysical parameters for uncontaminated areas estimated from resistivity are close to real values; meanwhile, in contaminated zones petrophysical parameters have anomalous values. Similar effects of contamination influence on petrophysical parameters were found in laboratory by resistivity measurements made at clean and contaminated sand samplers. [Spanish] El metodo Sondeo Electrico Vertical (SEV) es ampliamente utilizado en estudios de impacto ambiental incluyendo el caso de contaminacion por hidrocarburos. En este trabajo se presentan los resultados de la caracterizacion geoelectrica de un sitio contaminado por hidrocarburos relacionado con una fuga en linea de ducto. El estudio geoelectrico fue realizado utilizando el metodo SEV en la variante de tomografia, realizandose una interpretacion 2D de los datos observados. Seis perfiles paralelos de SEV fueron medidos y presentados sus resultados en secciones y mapas. Se determino un modelo estratificado que incluye acuitardo y acuifero. Aunque el grado de contaminacion en este sitio es bajo fue posible localizar dos zonas

  8. Analysis and evaluation of interwell seismic logging techniques for hydrocarbon reservoir characterization. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Parra, J.O.; Zook, B.J.; Sturdivant, V.R.

    1994-06-01

    The work reported herein represents the third year work in evaluating high-resolution interwell seismic logging techniques for hydrocarbon reservoir characterization. The objective of this project is to investigate interwell seismic logging techniques for indirectly interpreting oil and gas reservoir geology and rock physical properties. The work involves a balanced study of theoretical and numerical modeling of seismic waves transmitted between pairs of wells combined with experimental data acquisition and processing at controlled field conditions. The field applications of this reservoir probing concept are aimed at demonstrating high resolution measurements and detailed interpretation of heterogeneous hydrocarbon-bearing formations. The first part of this third year project efforts was devoted to thoroughly evaluating interwell seismic logging and reverse VSP in a hydrocarbon-bearing formation at the Buckhorn test site in Illinois. Specifically, the data from the experiments conducted in the second year of this project were analyzed to delineate geological structures and to extract rock physical parameters. The second part of this project is devoted to the evaluation of continuity logging techniques for hydrocarbon reservoir continuity. Specifically, this part of the project includes the evaluation of methods of measurements, modeling and data processing to delineate the reservoir architecture and relate dispersion and attenuation measurements to rock physical properties.

  9. Lithological architecture, geological processes and energy-field environments are major factors for the formation of hydrocarbon reservoirs

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wenzhi; WANG Zecheng; LI Xiaoqing; WANG Hongjun; WANG Zhaoyun

    2005-01-01

    The formation of hydrocarbon reservoirs is controlled by three major factors: lithological architecture, geological processes and energy-field environments. Among the three major factors, lithological architecture provides the storing medium for hydrocarbon; geological processes include hydrocarbon generation, migration, accumulation, preservation and modification; and energy-field environments refer to the various geothermal and geodynamic forces that affect the lithological architecture and drive the geological processes.In this study, we take Kela-2 and Sulige gas reservoirs as two examples to study relationships among the three major factors, and explain how these factors influence the scale and quality of hydrocarbon reservoirs.

  10. Polycyclic aromatic hydrocarbons in soils around Guanting Reservoir, Beijing, China

    NARCIS (Netherlands)

    Jiao, W.T.; Lu, Y.L.; Wang, T.Y.; Li, J.; Han, Jingyi; Wang, G.; Hu, W.Y.

    2009-01-01

    The concentrations of 16 polycyclic aromatic hydrocarbons ( 16PAHs) were measured by gas chromatography equipped with a mass spectrometry detector (GC-MS) in 56 topsoil samples around Guanting Reservior (GTR), which is an important water source for Beijing. Low to medium levels of PAH contamination

  11. Flow around fault zones in siliciclastic reservoirs based on limited available data during hydrocarbon exploration

    NARCIS (Netherlands)

    Heege, J.H. ter; Bruin, G. de

    2015-01-01

    The sealing capacity of faults is one of the main controlling factors determining column heights of hydrocarbons in structural traps and potentially bypassed gas in undrained reservoir compartments. Limited available data in early exploration phases often hampers full incorporation of fault seal ana

  12. Equation of state density models for hydrocarbons in ultradeep reservoirs at extreme temperature and pressure conditions

    Science.gov (United States)

    Wu, Yue; Bamgbade, Babatunde A.; Burgess, Ward A.; Tapriyal, Deepak; Baled, Hseen O.; Enick, Robert M.; McHugh, Mark A.

    2013-10-01

    The necessity of exploring ultradeep reservoirs requires the accurate prediction of hydrocarbon density data at extreme temperatures and pressures. In this study, three equations of state (EoS) models, Peng-Robinson (PR), high-temperature high-pressure volume-translated PR (HTHP VT-PR), and perturbed-chain statistical associating fluid theory (PC-SAFT) EoS are used to predict the density data for hydrocarbons in ultradeep reservoirs at temperatures to 523 K and pressures to 275 MPa. The calculated values are compared with experimental data. The results show that the HTHP VT-PR EoS and PC-SAFT EoS always perform better than the regular PR EoS for all the investigated hydrocarbons.

  13. Hydrocarbon charging histories of the Ordovician reservoir in the Tahe oil field, Tarim Basin, China

    Institute of Scientific and Technical Information of China (English)

    李纯泉; 陈红汉; 李思田; 张希明; 陈汉林

    2004-01-01

    The Ordovician reservoir of the Tahe oil field went through many tectonic reconstructions, and was charac-terized by multiple hydrocarbon chargings. The aim of this study was to unravel the complex charging histories. Systematicanalysis of fluid inclusions was employed to complete the investigation. Fluorescence observation of oil inclusions underUV light, and microthermometry of both oil and aqueous inclusions in 105 core samples taken from the Ordovician reservoirindicated that the Ordovician reservoir underwent four oil chargings and a gas charging. The hydrocarbon chargings oc-curred at the late Hercynian, the Indo-Sinian and Yanshan, the early Himalaya, the middle Himalaya, and the late Himalaya,respectively. The critical hydrocarbon charging time was at the late Hercynian.

  14. Petroleum, oil field waters, and authigenic mineral assemblages - Are they in metastable equilibrium in hydrocarbon reservoirs?

    Science.gov (United States)

    Helgeson, Harold C.; Knox, Annette M.; Owens, Christine E.; Shock, Everett L.

    1993-07-01

    The hypothesis that although the presence of carboxylic acids and carboxylate anions in oil field waters is commonly attributed to the thermal maturation of kerogen or bacterial degradation of hydrocarbons during water-washing of petroleum in relatively shallow reservoirs, they may have also been produced in deeper reservoirs by the hydrolysis of hydrocarbons in petroleum at the oil-water interface is tested. Calculations were carried out to determine the distribution of species with the minimum Gibbs free energy in overpressured oil field waters in the Texas Gulf Coast assuming metastable equilibrium among calcite, albite, and a representative spectrum of organic and inorganic aqueous species at reservoir temperatures and pressures. The hypothesis that homogeneous equilibrium obtains among carboxylate and carbonate species in oil field waters is confirmed.

  15. Kinetics of hydrocarbon generation for Well Yingnan 2 gas reservoir,Tarim Basin,CHina

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Well Yingnan 2,an important exploratory well in the east of Tarim Basin,yields high commercial oil and gas flow in Jurassic.Natural gas components and carbon isotopic composition indicate that it belongs to sapropel type gas.Because this region presents many suits of hydrocarbon source rocks,there are some controversies that natural gases were generated from kerogen gas or crude oil cracking gas at present.By using the kinetics of hydrocarbon generation and carbon isotope,natural gas of Well Yingnan 2 is composed mainly of crude oil cracking gas,about 72%,it is generated from secondary kerogen gas of Cambrian-Lower Ordovician source rock and crude oil cracking gas of Mid-Upper Ordovician oil reservoir.The main oil and gas filling time is 65 Ma later in the Jurassic gas reservoir of Well Yingnan 2,so the gas reservoir belongs to late accumulation and continuous filling type.

  16. Late Yanshan-Himalayan hydrocarbon reservoir adjustment and hydrotherrnal fluid activity in the central Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The adjustment of primary hydrocarbon reservoirs in marine formations is an important feature of the oil pools in the Tarim Basin. Large-scale hydrocarbon adjustment is related to the strong regional tectonic movements, which is always accompanied by extensive migration of basin fluids including diagenetic and mineralizing fluids. Organic fluid inclusions are well developed in hydrothermal minerals, such as fluorite, which have been found in the dissolution-enlarged fractures or karstification caves in the Ordovician in the central Tarim Basin. Proved by well drilling, the fluorite deposit is good reservoir for oil and gas. So the peculiar accompanied or superimposed relationship between fluorite hydrothermal fluid mineralization and hydrocarbon migration and accumulation exists in the Ordovician in the central Tarim Basin. Considering regional tectonic setting and mineralization condition,through different kinds of analytic methods including electron spin resonance dating, fluid inclusion laser Raman and colonial inclusions hydrocarbon fossil analysis, we proposed that extensive mineralizing fluids and hydrocarbon migration occurred in late Yanshan-Himalayan (110.4-30.8 Ma) period, and Himalayan, especially, is an important period for hydrocarbon accumulation from 34.3 Ma to present.

  17. Discrete fracture modeling of multiphase flow and hydrocarbon production in fractured shale or low permeability reservoirs

    Science.gov (United States)

    Hao, Y.; Settgast, R. R.; Fu, P.; Tompson, A. F. B.; Morris, J.; Ryerson, F. J.

    2016-12-01

    It has long been recognized that multiphase flow and transport in fractured porous media is very important for various subsurface applications. Hydrocarbon fluid flow and production from hydraulically fractured shale reservoirs is an important and complicated example of multiphase flow in fractured formations. The combination of horizontal drilling and hydraulic fracturing is able to create extensive fracture networks in low permeability shale rocks, leading to increased formation permeability and enhanced hydrocarbon production. However, unconventional wells experience a much faster production decline than conventional hydrocarbon recovery. Maintaining sustainable and economically viable shale gas/oil production requires additional wells and re-fracturing. Excessive fracturing fluid loss during hydraulic fracturing operations may also drive up operation costs and raise potential environmental concerns. Understanding and modeling processes that contribute to decreasing productivity and fracturing fluid loss represent a critical component for unconventional hydrocarbon recovery analysis. Towards this effort we develop a discrete fracture model (DFM) in GEOS (LLNL multi-physics computational code) to simulate multiphase flow and transfer in hydraulically fractured reservoirs. The DFM model is able to explicitly account for both individual fractures and their surrounding rocks, therefore allowing for an accurate prediction of impacts of fracture-matrix interactions on hydrocarbon production. We apply the DFM model to simulate three-phase (water, oil, and gas) flow behaviors in fractured shale rocks as a result of different hydraulic stimulation scenarios. Numerical results show that multiphase flow behaviors at the fracture-matrix interface play a major role in controlling both hydrocarbon production and fracturing fluid recovery rates. The DFM model developed in this study will be coupled with the existing hydro-fracture model to provide a fully integrated

  18. Hydrocarbon Reservoir Prediction Using Bi-Gaussian S Transform Based Time-Frequency Analysis Approach

    Science.gov (United States)

    Cheng, Z.; Chen, Y.; Liu, Y.; Liu, W.; Zhang, G.

    2015-12-01

    Among those hydrocarbon reservoir detection techniques, the time-frequency analysis based approach is one of the most widely used approaches because of its straightforward indication of low-frequency anomalies from the time-frequency maps, that is to say, the low-frequency bright spots usually indicate the potential hydrocarbon reservoirs. The time-frequency analysis based approach is easy to implement, and more importantly, is usually of high fidelity in reservoir prediction, compared with the state-of-the-art approaches, and thus is of great interest to petroleum geologists, geophysicists, and reservoir engineers. The S transform has been frequently used in obtaining the time-frequency maps because of its better performance in controlling the compromise between the time and frequency resolutions than the alternatives, such as the short-time Fourier transform, Gabor transform, and continuous wavelet transform. The window function used in the majority of previous S transform applications is the symmetric Gaussian window. However, one problem with the symmetric Gaussian window is the degradation of time resolution in the time-frequency map due to the long front taper. In our study, a bi-Gaussian S transform that substitutes the symmetric Gaussian window with an asymmetry bi-Gaussian window is proposed to analyze the multi-channel seismic data in order to predict hydrocarbon reservoirs. The bi-Gaussian window introduces asymmetry in the resultant time-frequency spectrum, with time resolution better in the front direction, as compared with the back direction. It is the first time that the bi-Gaussian S transform is used for analyzing multi-channel post-stack seismic data in order to predict hydrocarbon reservoirs since its invention in 2003. The superiority of the bi-Gaussian S transform over traditional S transform is tested on a real land seismic data example. The performance shows that the enhanced temporal resolution can help us depict more clearly the edge of the

  19. New hydrocarbon degradation pathways in the microbial metagenome from Brazilian petroleum reservoirs.

    Directory of Open Access Journals (Sweden)

    Isabel Natalia Sierra-García

    Full Text Available Current knowledge of the microbial diversity and metabolic pathways involved in hydrocarbon degradation in petroleum reservoirs is still limited, mostly due to the difficulty in recovering the complex community from such an extreme environment. Metagenomics is a valuable tool to investigate the genetic and functional diversity of previously uncultured microorganisms in natural environments. Using a function-driven metagenomic approach, we investigated the metabolic abilities of microbial communities in oil reservoirs. Here, we describe novel functional metabolic pathways involved in the biodegradation of aromatic compounds in a metagenomic library obtained from an oil reservoir. Although many of the deduced proteins shared homology with known enzymes of different well-described aerobic and anaerobic catabolic pathways, the metagenomic fragments did not contain the complete clusters known to be involved in hydrocarbon degradation. Instead, the metagenomic fragments comprised genes belonging to different pathways, showing novel gene arrangements. These results reinforce the potential of the metagenomic approach for the identification and elucidation of new genes and pathways in poorly studied environments and contribute to a broader perspective on the hydrocarbon degradation processes in petroleum reservoirs.

  20. New Hydrocarbon Degradation Pathways in the Microbial Metagenome from Brazilian Petroleum Reservoirs

    Science.gov (United States)

    Sierra-García, Isabel Natalia; Correa Alvarez, Javier; Pantaroto de Vasconcellos, Suzan; Pereira de Souza, Anete; dos Santos Neto, Eugenio Vaz; de Oliveira, Valéria Maia

    2014-01-01

    Current knowledge of the microbial diversity and metabolic pathways involved in hydrocarbon degradation in petroleum reservoirs is still limited, mostly due to the difficulty in recovering the complex community from such an extreme environment. Metagenomics is a valuable tool to investigate the genetic and functional diversity of previously uncultured microorganisms in natural environments. Using a function-driven metagenomic approach, we investigated the metabolic abilities of microbial communities in oil reservoirs. Here, we describe novel functional metabolic pathways involved in the biodegradation of aromatic compounds in a metagenomic library obtained from an oil reservoir. Although many of the deduced proteins shared homology with known enzymes of different well-described aerobic and anaerobic catabolic pathways, the metagenomic fragments did not contain the complete clusters known to be involved in hydrocarbon degradation. Instead, the metagenomic fragments comprised genes belonging to different pathways, showing novel gene arrangements. These results reinforce the potential of the metagenomic approach for the identification and elucidation of new genes and pathways in poorly studied environments and contribute to a broader perspective on the hydrocarbon degradation processes in petroleum reservoirs. PMID:24587220

  1. Microbial conversion of higher hydrocarbons to methane in oil and coal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, Martin; Beckmaann, Sabrina; Siegert, Michael; Grundger, Friederike; Richnow, Hans [Geomicrobiology Group, Federal Institute for Geosciences and Natural Resources (Germany)

    2011-07-01

    In recent years, oil production has increased enormously but almost half of the oil now remaining is heavy/biodegraded and cannot be put into production. There is therefore a need for new technology and for diversification of energy sources. This paper discusses the microbial conversion of higher hydrocarbons to methane in oil and coal reservoirs. The objective of the study is to identify microbial and geochemical controls on methanogenesis in reservoirs. A graph shows the utilization of methane for various purposes in Germany from 1998 to 2007. A degradation process to convert coal to methane is shown using a flow chart. The process for converting oil to methane is also given. Controlling factors include elements such as Fe, nitrogen and sulfur. Atmospheric temperature and reservoir pressure and temperature also play an important role. From the study it can be concluded that isotopes of methane provide exploration tools for reservoir selection and alkanes and aromatic compounds provide enrichment cultures.

  2. Calculation of Interfacial Tensions of Hydrocarbon-water Systems under Reservoir Conditions

    DEFF Research Database (Denmark)

    Zuo, You-Xiang; Stenby, Erling Halfdan

    1998-01-01

    Assuming that the number densities of each component in a mixture are linearly distributed across the interface between the coexisting vapor-liquid or liquid-liquid phases, we developed in this research work a linear-gradient-theory (LGT) model for computing the interfacial tension of hydrocarbon......-brine systems. The new model was tested on a number of hydrocarbon-water/brine mixtures and two crude oil-water systems under reservoir conditions. The results show good agreement between the predicted and the experimental interfacial tension data....

  3. Temperature and injection water source influence microbial community structure in four Alaskan North Slope hydrocarbon reservoirs.

    Directory of Open Access Journals (Sweden)

    Yvette Marisa Piceno

    2014-08-01

    Full Text Available A fundamental knowledge of microbial community structure in petroleum reservoirs can improve predictive modeling of these environments. We used hydrocarbon profiles, stable isotopes, and high-density DNA microarray analysis to characterize microbial communities in produced water from four Alaska North Slope hydrocarbon reservoirs. Produced fluids from Schrader Bluff (24-27°C, Kuparuk (47-70°C, Sag River (80°C, and Ivishak (80-83°C reservoirs were collected, with paired soured/non-soured wells sampled from Kuparuk and Ivishak. Chemical and stable isotope data suggested Schrader Bluff had substantial biogenic methane, whereas methane was mostly thermogenic in deeper reservoirs. Acetoclastic methanogens (Methanosaeta were most prominent in Schrader Bluff samples, and the combined δD and δ13C values of methane also indicated acetoclastic methanogenesis could be a primary route for biogenic methane. Conversely, hydrogenotrophic methanogens (e.g., Methanobacteriaceae and sulfide-producing Archaeoglobus and Thermococcus were more prominent in Kuparuk samples. Sulfide-producing microbes were detected in all reservoirs, uncoupled from souring status (e.g., the non-soured Kuparuk samples had higher relative abundances of many sulfate-reducers compared to the soured sample, suggesting sulfate-reducers may be living fermentatively/syntrophically when sulfate is limited. Sulfate abundance via long-term seawater injection resulted in greater relative abundances of Desulfonauticus, Desulfomicrobium, and Desulfuromonas in the soured Ivishak well compared to the non-soured well. In the non-soured Ivishak sample, several taxa affiliated with Thermoanaerobacter and Halomonas predominated. Archaea were not detected in the deepest reservoirs. Functional group taxa differed in relative abundance among reservoirs, likely reflecting differing thermal and/or geochemical influences.

  4. Time-Lapse Seismic Monitoring and Performance Assessment of CO2 Sequestration in Hydrocarbon Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Datta-Gupta, Akhil [Texas Engineering Experiment Station, College Station, TX (United States)

    2017-06-15

    Carbon dioxide sequestration remains an important and challenging research topic as a potentially viable approach for mitigating the effects of greenhouse gases on global warming (e.g., Chu and Majumdar, 2012; Bryant, 2007; Orr, 2004; Hepple and Benson, 2005; Bachu, 2003; Grimston et al., 2001). While CO2 can be sequestered in oceanic or terrestrial biomass, the most mature and effective technology currently available is sequestration in geologic formations, especially in known hydrocarbon reservoirs (Barrufet et al., 2010; Hepple and Benson, 2005). However, challenges in the design and implementation of sequestration projects remain, especially over long time scales. One problem is that the tendency for gravity override caused by the low density and viscosity of CO2. In the presence of subsurface heterogeneity, fractures and faults, there is a significant risk of CO2 leakage from the sequestration site into overlying rock compared to other liquid wastes (Hesse and Woods, 2010; Ennis-King and Patterson, 2002; Tsang et al., 2002). Furthermore, the CO2 will likely interact chemically with the rock in which it is stored, so that understanding and predicting its transport behavior during sequestration can be complex and difficult (Mandalaparty et al., 2011; Pruess et al., 2003). Leakage of CO2 can lead to such problems as acidification of ground water and killing of plant life, in addition to contamination of the atmosphere (Ha-Duong, 2003; Gasda et al., 2004). The development of adequate policies and regulatory systems to govern sequestration therefore requires improved characterization of the media in which CO2 is stored and the development of advanced methods for detecting and monitoring its flow and transport in the subsurface (Bachu, 2003).

  5. Effect of hydrocarbon to nuclear magnetic resonance (NMR) logging in tight sandstone reservoirs and method for hydrocarbon correction

    Science.gov (United States)

    Xiao, Liang; Mao, Zhi-qiang; Xie, Xiu-hong

    2017-04-01

    It is crucial to understand the behavior of the T2 distribution in the presence of hydrocarbon to properly interpret pore size distribution from NMR logging. The NMR T2 spectrum is associated with pore throat radius distribution under fully brine saturated. However, when the pore space occupied by hydrocarbon, the shape of NMR spectrum is changed due to the bulk relaxation of hydrocarbon. In this study, to understand the effect of hydrocarbon to NMR logging, the kerosene and transformer oil are used to simulate borehole crude oils with different viscosity. 20 core samples, which were separately drilled from conventional, medium porosity and permeability and tight sands are saturated with four conditions of irreducible water saturation, fully saturated with brine, hydrocarbon-bearing condition and residual oil saturation, and the corresponding NMR experiments are applied to acquire NMR measurements. The residual oil saturation is used to simulate field NMR logging due to the shallow investigation depth of NMR logging. The NMR spectra with these conditions are compared, the results illustrate that for core samples drilled from tight sandstone reservoirs, the shape of NMR spectra have much change once they pore space occupied by hydrocarbon. The T2 distributions are wide, and they are bimodal due to the effect of bulk relaxation of hydrocarbon, even though the NMR spectra are unimodal under fully brine saturated. The location of the first peaks are similar with those of the irreducible water, and the second peaks are close to the bulk relaxation of viscosity oils. While for core samples drilled from conventional formations, the shape of T2 spectra have little changes. The T2 distributions overlap with each other under these three conditions of fully brine saturated, hydrocarbon-bearing and residual oil. Hence, in tight sandstone reservoirs, the shape of NMR logging should be corrected. In this study, based on the lab experiments, seven T2 times of 1ms, 3ms, 10ms, 33ms

  6. Effect of Water Washing on Hydrocarbon Compositions of Petropleum Sandstone Reservoir Rocks in Tarim Basin,NW China

    Institute of Scientific and Technical Information of China (English)

    张敏; 张俊

    2000-01-01

    Gross compositions and distribution of saturated and aromatic hydrocarbons in Carboniferous sandstone reservoire rocks in oil and water zones for Tzhong-10 well of the Zhongyang Uplift in the Tarim Basin were studied in dteail by means of Rock-Eval Pyrolysis,thin-chromatograph-flame ionization detection(TLC-FID),gas chromatography,gas chromatography-mass spectrometry.The results suggest that the gross composition of reservoir hydrocarbons between the oil zone and the water zone show significant differences,Water wahing has a dramatic effect on saturated hydrocarbon blomarkers,especially drimane series compounds,Drimane series compounds in the water zone have been depleted completely.However,the contents of tricyclic iterpanes and pentacyclic triterpanes tend to decrease slightly,but the water-zone reservoir hydrocarbons contian a large amount of gammacerane.This suggests that gammacerane be more resistant to water washing than diterpanes and homohopanes.The contents of pregnane,homopregrane,diasteranes relastively decrease as a result of water washing.Water washing has a noticeable effect on polycyclic aromatic hydrocarbon compounds,especially aromatic sulfur compounds,and the contents of dibenzothiophene series compounds and benzonaplyiothipophene decrease significantly as a result of water washing.However,the conterts of bicyclic and tricyclic aromatic hydrocarbons decrase slightly and those of tetracyclic and pentacyclic aromatic hydrocarbons,especially benzofluoranthene and benzopyrenes,increase markedly owing to adecrease in light aromatie hydrocarbons as a result of water washing.

  7. Shale hydrocarbon reservoirs: some influences of tectonics and paleogeography during deposition: Chapter 2

    Science.gov (United States)

    Eoff, Jennifer D

    2014-01-01

    Continuous hydrocarbon accumulations in shale reservoirs appear to be characterized by common paleotectonic and paleogeographic histories and are limited to specific intervals of geologic time. In addition, most North American self-sourced shale correlates with geologic time periods of calcitic seas and greenhouse conditions and with evolutionary turnover of marine metazoans. More knowledge about the relations among these controls on deposition is needed, but conceptual modeling suggests that integrating tectonic histories, paleogeographic reconstructions, and eustatic curves may be a useful means by which to better understand shale plays already in development stages and potentially identify new organic-carbon-rich shale targets suitable for continuous resource development.

  8. Sequence of densification and hydrocarbon charging of Xu2 reservoir in Anyue-Hechuan area, Sichuan Basin, China

    Institute of Scientific and Technical Information of China (English)

    陈聪; 徐国盛; 徐昉昊; 袁海锋; 陈飞

    2016-01-01

    The sequence of the densification and hydrocarbon charging of the Xu2 reservoir in the Anyue–Hechuan area of Central Sichuan Basin is discussed. The diagenetic sequence is considered a time line to determine the historical relationship between the densification process and the hydrocarbon charging of the Xu2 reservoir in the study area:Early diagenetic stage B (the first stage of hydrocarbon charging, which was about 200–160 Ma ago, with a porosity of about 20%, consolidated and not tight) → middle diagenetic stage A (the second stage of hydrocarbon charging, which was about 140–120 Ma ago, with a porosity of 10%–20%and relatively tight) → middle diagenetic stage B (the third stage of hydrocarbon charging, which was about 20–5 Ma ago, with a porosity of 6%–10%and tight;However, fractures have developed). The study results prove that large-scale hydrocarbon charging and accumulation completed before the densification of the Xu2 reservoir, showing that the Upper Triassic Xujiahe Fm unconventional tight reservoir in the Sichuan Basin is prospective for exploration.

  9. Caprock Integrity during Hydrocarbon Production and CO2 Injection in the Goldeneye Reservoir

    Science.gov (United States)

    Salimzadeh, Saeed; Paluszny, Adriana; Zimmerman, Robert

    2016-04-01

    Carbon Capture and Storage (CCS) is a key technology for addressing climate change and maintaining security of energy supplies, while potentially offering important economic benefits. UK offshore, depleted hydrocarbon reservoirs have the potential capacity to store significant quantities of carbon dioxide, produced during power generation from fossil fuels. The Goldeneye depleted gas condensate field, located offshore in the UK North Sea at a depth of ~ 2600 m, is a candidate for the storage of at least 10 million tons of CO2. In this research, a fully coupled, full-scale model (50×20×8 km), based on the Goldeneye reservoir, is built and used for hydro-carbon production and CO2 injection simulations. The model accounts for fluid flow, heat transfer, and deformation of the fractured reservoir. Flow through fractures is defined as two-dimensional laminar flow within the three-dimensional poroelastic medium. The local thermal non-equilibrium between injected CO2 and host reservoir has been considered with convective (conduction and advection) heat transfer. The numerical model has been developed using standard finite element method with Galerkin spatial discretisation, and finite difference temporal discretisation. The geomechanical model has been implemented into the object-oriented Imperial College Geomechanics Toolkit, in close interaction with the Complex Systems Modelling Platform (CSMP), and validated with several benchmark examples. Fifteen major faults are mapped from the Goldeneye field into the model. Modal stress intensity factors, for the three modes of fracture opening during hydrocarbon production and CO2 injection phases, are computed at the tips of the faults by computing the I-Integral over a virtual disk. Contact stresses -normal and shear- on the fault surfaces are iteratively computed using a gap-based augmented Lagrangian-Uzawa method. Results show fault activation during the production phase that may affect the fault's hydraulic conductivity

  10. Study on the enhancement of hydrocarbon recovery by characterization of the reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Kwak, Young Hoon; Son, Jin Dam; Oh, Jae Ho [Korea Institute of Geology Mining and Materials, Taejon (Korea)] [and others

    1998-12-01

    Three year project is being carried out on the enhancement of hydrocarbon recovery by the reservoir characterization. This report describes the results of the second year's work. This project deals with characterization of fluids, bitumen ad rock matrix in the reservoir. New equipment and analytical solutions for naturally fractured reservoir were also included in this study. Main purpose of the reservoir geochemistry is to understand the origin of fluids (gas, petroleum and water) and distribution of the bitumens within the reservoir and to use them not only for exploration but development of the petroleum. For the theme of reservoir geochemistry, methods and principles of the reservoir gas and bitumen characterization, which is applicable to the petroleum development, are studied. and case study was carried out on the gas, water and bitumen samples in the reservoir taken form Haenam area and Ulleung Basin offshore Korea. Gases taken form the two different wells indicate the different origin. Formation water analyses show the absence of barrier within the tested interval. With the sidewall core samples from a well offshore Korea, the analysis using polarizing microscope, scanning electron microscope with EDX and cathodoluminoscope was performed for the study on sandstone diagenesis. The I/S changes were examined on the cuttings samples from a well, offshore Korea to estimate burial temperature. Oxygen stable isotope is used to study geothermal history in sedimentary basin. Study in the field is rare in Korea and basic data are urgently needed especially in continental basins to determine the value of formation water. In the test analyses, three samples from marine basins indicate final temperature from 55 deg.C to 83 deg.C and one marine sample indicate the initial temperature of 36 deg.C. One sample from continental basin represented the final temperature from 53 and 80 deg.C. These temperatures will be corrected because these values were based on assumed

  11. A spectral-geophysical approach for detecting pipeline leakage

    Science.gov (United States)

    van der Meijde, M.; van der Werff, H. M. A.; Jansma, P. F.; van der Meer, F. D.; Groothuis, G. J.

    2009-02-01

    Leakage of hydrocarbon has a large economic and environmental impact. Traditional methods for investigating leakage and resulting pollution, such as drilling, are destructive, time consuming and expensive. Remote sensing is an alternative that is non-destructive and has been been tested extensively for exploration of onshore hydrocarbon reservoirs and detection of hydrocarbons at the Earth's surface. In this research, a leaking pipeline is investigated through field reflectance spectrometry and the findings are validated with traditional drilling and geophysical measurements. The measurements show a significant increase of vegetation anomalies on the pipeline with respect to areas further away. The observed anomalies are positively related to hydrocarbon pollution through chemical analysis of drillings. Subsurface geophysical measurements show a large correlation with observed surface vegetation stress, enhancing the identification of hydrocarbon-related vegetation stress through spectroscopy.

  12. Evolution of hydrocarbon migration style in a fractured reservoir deduced from fluid inclusion data, Clair Field, west of Shetland, UK

    Energy Technology Data Exchange (ETDEWEB)

    Baron, Martin; Parnell, John; Mark, Darren [Department of Geology and Petroleum Geology, Meston Building, University of Aberdeen, King' s College, Aberdeen AB24 3UE (United Kingdom); Carr, Andrew [Advanced Geochemical Systems Ltd., Towles Fields, Burton on the Wolds, Leicestershire LE12 5TD (United Kingdom); British Geological Survey, Keyworth, Nottingham NG12 5GG (United Kingdom); Przyjalgowski, Milosz [Department of Physics, National University of Ireland-Galway, Galway (Ireland); Feely, Martin [Department of Geology, National University of Ireland-Galway, Galway (Ireland)

    2008-02-15

    A petrographic and fluid inclusion microthermometric study was performed on sandstones from the Devonian-Carboniferous reservoir rocks of the Clair Field, west of Shetland. Fluid inclusion petrographic and microthermometric observations were collected from quartz, K-feldspar and calcite cements and veins. Vein and cement minerals host both aqueous and hydrocarbon two-phase (liquid and vapor-filled) fluid inclusions indicating that cementation occurred during oil charging. The location of hydrocarbon fluid inclusions in the paragenetic sequence of the reservoir rocks indicates that hydrocarbon migration during early-stage diagenesis occurred via intergranular pores as well as fractures, whereas towards the later stages of diagenesis, as porosities were occluded, hydrocarbon migration was predominantly fracture controlled. The microthermometric characteristics of primary and secondary aqueous fluid inclusions in association with hydrocarbon fluid inclusions indicates that cementation and veining during oil charging occurred at temperatures up to 180 C. Salinity values are variable (0-10.9 wt% NaCl eq.) indicating that fluid mixing occurred during veining and cementation. Basin modeling and vitrinite reflectance data indicate that temperatures of up to 180 C could not have been attained through burial alone. The high temperatures attained during late-stage diagenesis are interpreted to be caused by high temperature, short-lived fluids circulating within the Devonian-Carboniferous reservoir rocks in association with late Cretaceous and Paleocene magmatism. These high temperature fluid flow events were not recorded in the vitrinite reflectance data because of their short duration. (author)

  13. Origin of the Tertiary reservoired hydrocarbons along the central Texas and Louisiana Gulf Coast rim

    Energy Technology Data Exchange (ETDEWEB)

    Cole, G.A.; Sassen, R. (BP Exploration, Inc., Houston, TX (USA)); Chinn, E.W. (Louisiana State Univ., Baton Rouge (USA)); Piggott, N.; Gibbons, M.J.

    1990-05-01

    Tertiary reservoired hydrocarbons along the central Texas and Louisiana Gulf Coast rim were most likely derived from Paleocene/Eocene Wilcox Group and Sparta Formation marine shales. Sixteen total soluble extracts and >200 oil samples were analyzed using carbon isotopic techniques ({delta}{sup 13}C) and gas chromatography-mass spectometry (GC-MS). Results demonstrated that interpretations must use all types of data because Cretaceous derived and Tertiary derived oils overlap in southern Louisiana. When isotopic, sterane, hopane, and light hydrocarbon data are combined separation of classes become possible. Cretaceous oils and extracts have a full range of extended hopanes, a characteristic peak eluting immediately after C{sub 30} hopane and no oleanane. Paleogene oils and extracts have oleanane and a restricted range of extended hopanes. Regional trends indicate that eastern Louisiana oils were derived from the Sparta or a Sparta/Wilcox mix, the Mississippi delta oils from a Cretaceous clastic source, and western Louisiana and Texas oils from the Wilcox source. Regional variations in GOR/CGR are a function of timing and mechanism of migration.

  14. Deformation bands evolving from dilation to cementation bands in a hydrocarbon reservoir (Vienna Basin, Austria)

    Science.gov (United States)

    Exner, Ulrike; Kaiser, Jasmin; Gier, Susanne

    2013-01-01

    In this study we analyzed five core samples from a hydrocarbon reservoir, the Matzen Field in the Vienna Basin (Austria). Deformation bands occur as single bands or as strands of several bands. In contrast to most published examples of deformation bands in terrigeneous sandstones, the reduction of porosity is predominantly caused by the precipitation of Fe-rich dolomite cement within the bands, and only subordinately by cataclasis of detrital grains. The chemical composition of this dolomite cement (10–12 wt% FeO) differs from detrital dolomite grains in the host rock (<2 wt% FeO). This observation in combination with stable isotope data suggests that the cement is not derived from the detrital grains, but precipitated from a fluid from an external, non-meteoric source. After an initial increase of porosity by dilation, disaggregation and fragmentation of detrital grains, a Fe-rich carbonate fluid crystallized within the bands, thereby reducing the porosity relative to the host sediment. The retention of pyrite cement by these cementation bands as well as the different degree of oil staining on either side of the bands demonstrate that these cementation bands act as effective barriers to the migration of fluids and should be considered in reservoir models. PMID:26321782

  15. Atmospheric and soil-gas monitoring for surface leakage at the San Juan Basin CO{sub 2} pilot test site at Pump Canyon New Mexico, using perfluorocarbon tracers, CO{sub 2} soil-gas flux and soil-gas hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Wells, Arthur W; Diehl, J Rodney; Strazisar, Brian R; Wilson, Thomas; H Stanko, Dennis C

    2012-05-01

    Near-surface monitoring and subsurface characterization activities were undertaken in collaboration with the Southwest Regional Carbon Sequestration Partnership on their San Juan Basin coal-bed methane pilot test site near Navajo City, New Mexico. Nearly 18,407 short tons (1.670 × 107 kg) of CO{sub 2} were injected into 3 seams of the Fruitland coal between July 2008 and April 2009. Between September 18 and October 30, 2008, two additions of approximately 20 L each of perfluorocarbon (PFC) tracers were mixed with the CO{sub 2} at the injection wellhead. PFC tracers in soil-gas and in the atmosphere were monitored over a period of 2 years using a rectangular array of permanent installations. Additional monitors were placed near existing well bores and at other locations of potential leakage identified during the pre-injection site survey. Monitoring was conducted using sorbent containing tubes to collect any released PFC tracer from soil-gas or the atmosphere. Near-surface monitoring activities also included CO{sub 2} surface flux and carbon isotopes, soil-gas hydrocarbon levels, and electrical conductivity in the soil. The value of the PFC tracers was demonstrated when a significant leakage event was detected near an offset production well. Subsurface characterization activities, including 3D seismic interpretation and attribute analysis, were conducted to evaluate reservoir integrity and the potential that leakage of injected CO{sub 2} might occur. Leakage from the injection reservoir was not detected. PFC tracers made breakthroughs at 2 of 3 offset wells which were not otherwise directly observable in produced gases containing 20–30% CO{sub 2}. These results have aided reservoir geophysical and simulation investigations to track the underground movement of CO{sub 2}. 3D seismic analysis provided a possible interpretation for the order of appearance of tracers at production wells.

  16. Reservoir attributes of a hydrocarbon-prone sandstone complex: case of the Pab Formation (Late Cretaceous) of Southwest Pakistan

    DEFF Research Database (Denmark)

    Umar, Muhammad; Khan, Abdul Salam; Kelling, Gilbert;

    2016-01-01

    Links between the architectural elements of major sand bodies and reservoir attributes have been explored in a field study of the hydrocarbon-yielding Late Cretaceous Pab Formation of southwest Pakistan. The lithofacies and facies associations represented in the Pab Formation are the main...... porosity values than more shale-rich successions. Diagenetic studies of Pab sandstones reveal that intense mechanical compaction and cementation have reduced primary porosity and reservoir quality. Conversely, dissolution of detrital feldspar grains and volcanic fragments during burial and later uplift...

  17. Distribution, sources and potential toxicological significance of polycyclic aromatic hydrocarbons(PAHs) in Guanting Reservoir sediments, China

    Institute of Scientific and Technical Information of China (English)

    HUANG Sheng-biao; WANG Zi-jian; XU Yi-ping; MA Mei

    2005-01-01

    The Guanting Reservoir lost its function as the second biggest drinking water source for Beijing due to the pollutions from the upstream flow of Yongding River in 1997. From 1998, lots of studies were carryied out to renew the function of Guanting Reservoir as domestic drinking water source before 2008 Olympic Games. This is the first time that polycyclic aromatic hydrocarbon concentrations in the surface sediment of Guanting Reservoir have been analyzed. A distinctive spatial distribution of PAHs was observed. Sediments from four sites along Inlet of Yongding River to reservoir bam had PAHs concentrations of 1377-2855 μg/g dw in descending order. The composition of PAHs is investigated and used to assess petrogenic,combustion and naturally derived of the sediments samples of Guanting Reservoir. Special PAHs ratios, such as phenanthrene/anthracene(P/A) and fluoranthene/pyrene(FI/Pyr) were calculated to assess the relative importance of different origins. The data confirmed a relatively high level of petrogenic contamination in four sites. These high PAHs levels were associated with the input of untreated and partially treated industrial sewage. In addition, the concentrations of PAHs compounds of samples indicated that sediments of reservoir were most likely to pose potential biological impairment.

  18. Isotopic and geochemical tools to assess the feasibility of methanogenesis as a way to enhance hydrocarbon recovery in oil reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, N.; Morris, B.E.L.; Richnow, H.H. [Helmholtz-Zentrum fuer Umweltforschung (UFZ), Leipzig (Germany). Abt. Isotopenbiogeochemie; Cai, M.; Yao, Jun [Helmholtz-Zentrum fuer Umweltforschung (UFZ), Leipzig (Germany). Abt. Isotopenbiogeochemie; University of Sicence and Technology, Beijing (China). School of Civil and Environment Engineering; Straaten, N.; Krueger, M. [Bundesanstalt fuer Geowissenschaften und Rohstoffe (BGR), Hannover (Germany). Fachbereich Geochemie

    2013-08-01

    In situ biotransformation of oil to methane was investigated in a thermophilic reservoir in Dagang, China using isotopic analyzes, chemical fingerprinting and molecular and biological methods. Our first results, which were already published, demonstrated that anaerobic oil degradation concomitant with methane production was occurring. The reservoir was highly methanogenic and the oil exhibited varying degrees of degradation between different parts of the reservoir, although it was mainly highly weathered, and nearly devoid of nalkanes, alkylbenzenes, alkyltoluenes, and light PAHs. In addition, the isotopic data from reservoir oil, water and gas was used to elucidate the origin of the methane. The average {delta}{sup 13}C for methane was around -47 permille and CO{sub 2} was highly enriched in {sup 13}C. The bulk isotopic discrimination ({Delta}{delta}{sup 13}C) between methane and CO{sub 2} was between 32 and 65 permille, in accordance with previously reported results for methane formation during hydrocarbon degradation. Subsequent microcosm experiments revealed that autochthonous microbiota are capable of degrading oil under methanogenic conditions and of producing methane and/or CO{sub 2} from {sup 13}C-labelled n-hexadecane, 2-methylnaphthalene or toluene ({delta}{sup 13}C values up to 550 permille). These results demonstrate that methanogenesis is linked to aliphatic and aromatic hydrocarbon degradation. Further experiments will elucidate the activation mechanisms for the different compounds. (orig.)

  19. Remaining gaps for "safe" CO2 storage: the INGV CO2GAPS vision of "learning by doing" monitoring geogas leakage, reservoirs contamination/mixing and induced/triggered seismicity

    Science.gov (United States)

    Quattrocchi, F.; Vinciguerra, S.; Chiarabba, C.; Boschi, E.; Anselmi, M.; Burrato, P.; Buttinelli, M.; Cantucci, B.; Cinti, D.; Galli, G.; Improta, L.; Nazzari, M.; Pischiutta, M.; Pizzino, L.; Procesi, M.; Rovelli, A.; Sciarra, A.; Voltattorni, N.

    2012-12-01

    The CO2GAPS project proposed by INGV is intended to build up an European Proposal for a new kind of research strategy in the field of the geogas storage. Aim of the project would be to fill such key GAPS concerning the main risks associated to CO2 storage and their implications on the entire Carbon Capture and Storage (CCS) process, which are: i) the geogas leakage both in soils and shallow aquifers, up to indoor seepage; ii) the reservoirs contamination/mixing by hydrocarbons and heavy metals; iii) induced or triggered seismicity and microseismicity, especially for seismogenic blind faults. In order to consider such risks and make the CCS public acceptance easier, a new kind of research approach should be performed by: i) a better multi-disciplinary and "site specific" risk assessment; ii) the development of more reliable multi-disciplinary monitoring protocols. In this view robust pre-injection base-lines (seismicity and degassing) as well as identification and discrimination criteria for potential anomalies are mandatory. CO2 injection dynamic modelling presently not consider reservoirs geomechanical properties during reactive mass-transport large scale simulations. Complex simulations of the contemporaneous physic-chemical processes involving CO2-rich plumes which move, react and help to crack the reservoir rocks are not totally performed. These activities should not be accomplished only by the oil-gas/electric companies, since the experienced know-how should be shared among the CCS industrial operators and research institutions, with the governments support and overview, also flanked by a transparent and "peer reviewed" scientific popularization process. In this context, a preliminary and reliable 3D modelling of the entire "storage complex" as defined by the European Directive 31/2009 is strictly necessary, taking into account the above mentioned geological, geochemical and geophysical risks. New scientific results could also highlighting such opportunities

  20. Impact of CO2 leakage from sub-seabed carbon dioxide capture and storage (CCS) reservoirs on benthic virus-prokaryote interactions and functions.

    Science.gov (United States)

    Rastelli, Eugenio; Corinaldesi, Cinzia; Dell'Anno, Antonio; Amaro, Teresa; Queirós, Ana M; Widdicombe, Stephen; Danovaro, Roberto

    2015-01-01

    Atmospheric CO2 emissions are a global concern due to their predicted impact on biodiversity, ecosystems functioning, and human life. Among the proposed mitigation strategies, CO2 capture and storage, primarily the injection of CO2 into marine deep geological formations has been suggested as a technically practical option for reducing emissions. However, concerns have been raised that possible leakage from such storage sites, and the associated elevated levels of pCO2 could locally impact the biodiversity and biogeochemical processes in the sediments above these reservoirs. Whilst a number of impact assessment studies have been conducted, no information is available on the specific responses of viruses and virus-host interactions. In the present study, we tested the impact of a simulated CO2 leakage on the benthic microbial assemblages, with specific focus on microbial activity and virus-induced prokaryotic mortality (VIPM). We found that exposure to levels of CO2 in the overlying seawater from 1,000 to 20,000 ppm for a period up to 140 days, resulted in a marked decrease in heterotrophic carbon production and organic matter degradation rates in the sediments, associated with lower rates of VIPM, and a progressive accumulation of sedimentary organic matter with increasing CO2 concentrations. These results suggest that the increase in seawater pCO2 levels that may result from CO2 leakage, can severely reduce the rates of microbial-mediated recycling of the sedimentary organic matter and viral infections, with major consequences on C cycling and nutrient regeneration, and hence on the functioning of benthic ecosystems.

  1. The potential for hydrocarbon biodegradation and production of extracellular polymeric substances by aerobic bacteria isolated from a Brazilian petroleum reservoir.

    Science.gov (United States)

    Vasconcellos, S P; Dellagnezze, B M; Wieland, A; Klock, J-H; Santos Neto, E V; Marsaioli, A J; Oliveira, V M; Michaelis, W

    2011-06-01

    Extracellular polymeric substances (EPS) can contribute to the cellular degradation of hydrocarbons and have a huge potential for application in biotechnological processes, such as bioremediation and microbial enhanced oil recovery (MEOR). Four bacterial strains from a Brazilian petroleum reservoir were investigated for EPS production, emulsification ability and biodegradation activity when hydrocarbons were supplied as substrates for microbial growth. Two strains of Bacillus species had the highest EPS production when phenanthrene and n-octadecane were offered as carbon sources, either individually or in a mixture. While Pseudomonas sp. and Dietzia sp., the other two evaluated strains, had the highest hydrocarbon biodegradation indices, EPS production was not detected. Low EPS production may not necessarily be indicative of an absence of emulsifier activity, as indicated by the results of a surface tension reduction assay and emulsification indices for the strain of Dietzia sp. The combined results gathered in this work suggest that a microbial consortium consisting of bacteria with interdependent metabolisms could thrive in petroleum reservoirs, thus overcoming the limitations imposed on each individual species by the harsh conditions found in such environments.

  2. The applicability of C-14 measurements in the soil gas for the assessment of leakage out of underground carbon dioxide reservoirs

    Directory of Open Access Journals (Sweden)

    Chałupnik Stanisław

    2014-03-01

    Full Text Available Poland, due to the ratification of the Kioto Protocol, is obliged to diminish the emission of greenhouse gases. One of the possible solutions of this problem is CO2 sequestration (CCS - carbon capture and storage. Such an option is a priority in the European Union. On the other hand, CO2 sequestration may be potentially risky in the case of gas leakage from underground reservoirs. The most dangerous event may be a sudden release of the gas onto the surface. Therefore, it is very important to know if there is any escape of CO2 from underground gas reservoirs, created as a result of sequestration. Such information is crucial to ensure safety of the population in areas located above geological reservoirs. It is possible to assess the origin of carbon dioxide, if the measurement of radiocarbon 14C concentration in this gas is done. If CO2 contains no 14C, it means, that the origin of the gas is either geological or the gas has been produced as a result of combustion of fossil fuels, like coal. A lot of efforts are focused on the development of monitoring methods to ensure safety of CO2 sequestration in geological formations. A radiometric method has been tested for such a purpose. The main goal of the investigations was to check the application possibility of such a method. The technique is based on the liquid scintillation counting of samples. The gas sample is at first bubbled through the carbon dioxide adsorbent, afterwards the adsorbent is mixed with a dedicated cocktail and measured in a low-background liquid scintillation spectrometer Quantulus. The described method enables measurements of 14C in mine and soil gas samples.

  3. Reservoir leakage along concentric faults in the Southern North Sea: Implications for the deployment of CCS and EOR techniques

    Science.gov (United States)

    Ward, Nicholas I. P.; Alves, Tiago M.; Blenkinsop, Tom G.

    2016-10-01

    High-quality 3D seismic and borehole data in the Broad Fourteens Basin, Southern North Sea, is used to investigate newly recognised concentric faults formed in salt-withdrawal basins flanking reactivated salt structures. Throw-depth and throw-distance plots were used to understand the growth histories of individual faults. As a result, three families of concentric faults are identified: a) intra-seal faults within a salt-withdrawal basin, b) faults connecting the seal and the reservoir on the crest of an inverted anticline, c) raft-bounding faults propagating into reservoir units. They have moved obliquely and show normal throws, even though they formed during a period of regional compression. Faults in the salt-withdrawal basin and on the inverted anticline are highly segmented, increasing the chances of compartmentalisation or localised fluid flow through fault linkages. Slip tendency analysis was carried out on the distinct fault families to compare the likelihood of slip along a fault at different pore fluid pressures and within different lithologies. Our results show that sections of the faults are optimally oriented with regards to maximum horizontal stresses (σHmax), increasing the slip tendency. The identified faults cut through a variety of lithologies, allowing different values of pore fluid pressures to build up before faults reactivate. Within the Vlieland Sandstones, pore fluid pressures of 30 MPa are not sufficient to reactivate pre-existing faults, whereas in the deeper Posidonia Shales faults might reactivate at pore fluid pressures of 25 MPa. Fluid flow features preferentially occur near fault segments close to failure. Heterogeneity in slip tendency along concentric faults, and high degrees of fault segmentation, present serious hazards when injecting CO2 into the subsurface. This study stresses the importance of high-quality 3D seismic data and the need to evaluate individual fault systems when investigating potential reservoirs for carbon

  4. North-south Differentiation of the Hydrocarbon Accumulation Pattern of Carbonate Reservoirs in the Yingmaili Low Uplift, Tarim Basin,Northwest China

    Institute of Scientific and Technical Information of China (English)

    L(U) Xiuxiang; LI Jianjiao; ZHAO Fengyun; YANG Ning; ZHANG Qiucha

    2008-01-01

    By analyzing the characteristics of development, structural evolution and reservoir beds of the residual carbonate strata, this study shows that the residual carbonate strata in the Yingmaili low uplift are favorable oil and gas accumulation series in the Tabei (northern Tarim uplift) uplift. There are different patterns of hydrocarbon accumulation on the northern and southern slopes of the Yingmaili low uplift. The north-south differentiation of oil reservoirs were caused by different lithologies of the residual carbonate strata and the key constraints on the development of the reservoir beds. The Mesozoic terrestrial organic matter in the Kuqa depression and the Palaeozoic marine organic matter in the Manjiaer sag of the Northern depression are the major hydrocarbon source rocks for the northern slope and southern slope respectively. The hydrocarbon accumulation on the northern and southern slopes is controlled by differences in maturity and thermal evolution history of these two kinds of organic matter. On the southern slope, the oil accumulation formed in the early stage was destroyed completely, and the period from the late Hercynian to the Himalayian is the most important time for hydrocarbon accumulation. However, the time of hydrocarbon accumulation on the northern slope began 5 Ma B.P. Carbonate inner buried anticlines reservoirs are present on the southern slope, while weathered crust and paleo-buried hill karst carbonate reservoirs are present on the northern slope. The northern and southern slopes had different controlling factors of hydrocarbon accumulation respectively. Fracture growth in the reservoir beds is the most important controlling factor on the southern slope; while hydrocarbon accumulation on the northern slope is controlled by weathered crust and cap rock.

  5. Spatial distribution of hydrocarbon reservoirs in the West Korea Bay Basin in the northern part of the Yellow Sea, estimated by 3-D gravity forward modelling

    Science.gov (United States)

    Choi, Sungchan; Ryu, In-Chang; Götze, H.-J.; Chae, Y.

    2017-01-01

    Although an amount of hydrocarbon has been discovered in the West Korea Bay Basin (WKBB), located in the North Korean offshore area, geophysical investigations associated with these hydrocarbon reservoirs are not permitted because of the current geopolitical situation. Interpretation of satellite-derived potential field data can be alternatively used to image the 3-D density distribution in the sedimentary basin associated with hydrocarbon deposits. We interpreted the TRIDENT satellite-derived gravity field data to provide detailed insights into the spatial distribution of sedimentary density structures in the WKBB. We used 3-D forward density modelling for the interpretation that incorporated constraints from existing geological and geophysical information. The gravity data interpretation and the 3-D forward modelling showed that there are two modelled areas in the central subbasin that are characterized by very low density structures, with a maximum density of about 2000 kg m-3, indicating some type of hydrocarbon reservoir. One of the anticipated hydrocarbon reservoirs is located in the southern part of the central subbasin with a volume of about 250 km3 at a depth of about 3000 m in the Cretaceous/Jurassic layer. The other hydrocarbon reservoir should exist in the northern part of the central subbasin, with an average volume of about 300 km3 at a depth of about 2500 m.

  6. Reservoir structures detection and hydrocarbons exploration using wavelet transform method in 2 oil fields in southwestern of Iran

    Science.gov (United States)

    Hassani, H.; Saadatinejad, M. R.

    2012-04-01

    reservoirs and differ for limestone and sandstone. In this way, CWT applied on vertical sections and in 4 different iso-frequency displaying. By comparing these figures at 10, 16, 24 and 32 Hz, the presence of low frequency shadows under reservoir could be seen. These shadows have distinctly different dynamic frequency responses rather than the background, probably because the hydrocarbons have changed the reflectivity of the reservoir as the anomalies at 10 Hz are bright. In the 16 Hz section, anomalies almost stand out, and the difference between them becomes relatively weak; yet, some of them are still brighter than other anomalies at higher frequencies. Consequently, these variations of anomalies at different frequencies can consider as indicator from presence of hydrocarbons in the target reservoir. Finally, selecting a suitable wavelet is important step of CWT method and in all mentioned usages, Morlet wavelet has beneficial properties to applying in our investigation. In fact, Morlet wavelet demonstrates velocity dispersion and energy absorption to identify fault and gas respectively.

  7. Study on the enhancement of hydrocarbon recovery by characterization of the reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Tae-Jin; Kwak, Young-Hoon; Huh, Dae-Gee [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)

    1999-12-01

    The reservoir geochemistry is to understand the origin of these heterogeneities and distributions of the bitumens within the reservoir and to use them not only for exploration but for the development of the petroleums. Methods and principles of the reservoir geochemistry, which are applicable to the petroleum exploration and development, are reviewed in the study. In addition, a case study was carried out on the gas, condensate, water and bitumen samples in the reservoir, taken from the Haenam, Pohang areas and the Ulleung Basin offshore Korea. Mineral geothermometers were studied to estimate the thermal history in sedimentary basins and successfully applied to the Korean onshore and offshore basins. The opal silica-to-quartz transformation was investigated in the Pohang basin as a geothermometer. In Korean basins, the smectite-to-illite changes indicate that smectite and illite can act as the geothermometer to estimate the thermal history of the basins. The albitization reaction was also considered as a temperature indicator. Naturally fractured reservoir is an important source of oil and gas throughout the world. The properties of matrix and fracture are the key parameters in predicting the performances of naturally fractured reservoirs. A new laboratory equipment has been designed and constructed by pressure pulse method to determine the properties, which are (1) the porosity of matrix, (2) the permeability of matrix, (3) the effective width of the fractures, and the permeability of the fractures. (author). 97 refs.

  8. Study on the enhancement of hydrocarbon recovery by characterization of the reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Tae-Jin; Kwak, Young-Hoon; Huh, Dae-Gee [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)

    1999-12-01

    The reservoir geochemistry is to understand the origin of these heterogeneities and distributions of the bitumens within the reservoir and to use them not only for exploration but for the development of the petroleums. Methods and principles of the reservoir geochemistry, which are applicable to the petroleum exploration and development, are reviewed in the study. In addition, a case study was carried out on the gas, condensate, water and bitumen samples in the reservoir, taken from the Haenam, Pohang areas and the Ulleung Basin offshore Korea. Mineral geothermometers were studied to estimate the thermal history in sedimentary basins and successfully applied to the Korean onshore and offshore basins. The opal silica-to-quartz transformation was investigated in the Pohang basin as a geothermometer. In Korean basins, the smectite-to-illite changes indicate that smectite and illite can act as the geothermometer to estimate the thermal history of the basins. The albitization reaction was also considered as a temperature indicator. Naturally fractured reservoir is an important source of oil and gas throughout the world. The properties of matrix and fracture are the key parameters in predicting the performances of naturally fractured reservoirs. A new laboratory equipment has been designed and constructed by pressure pulse method to determine the properties, which are (1) the porosity of matrix, (2) the permeability of matrix, (3) the effective width of the fractures, and the permeability of the fractures. (author). 97 refs.

  9. 3D modelling of a dolomitized syn-sedimentary structure: an exhumed potential analogue of hydrocarbon reservoir.

    Science.gov (United States)

    Martinelli, Mattia; Franceschi, Marco; Massironi, Matteo; Bistacchi, Andrea; Di Cuia, Raffaele; Rizzi, Alessandro

    2016-04-01

    The decrease in discoveries of new hydrocarbon reservoirs has twofold implications: i) the need to improve our knowledge of classic reservoirs, such as traps within extensional syn-sedimentary structures, and ii) enhanced efforts aimed at better understanding complex type of reservoirs. In particular, in the last few years, fault related dolomitized bodies, often associated to extensional faults, received worldwide attention thanks to the capability of dolomitizing fluids to improve the pore network. However, the shape and geometries of the dolomitized bodies within complex fault network as well as the related porosity distribution and evolution is difficult to predict. The study of outcrop analogues can help to solve these issues. In this work, we focused our attention on the Early Jurassic carbonate sediments of the Calcari Grigi Group deposited on the Trento Platform (Italian Southern Alps). The stratigraphic succession encompasses (from bottom to top): the peritidal limestones of the Monte Zugna Formation, the initially highly porous Loppio Oolitic Limestone and the nearly tight marls and marly limestones of the lower Rotzo Formation. During Early Jurassic, after the deposition of the Loppio Oolitic Limestone, the Trento Platform underwent syn-sedimentary extensional tectonics, which caused the formation of numerous tilted blocks. Differential subsidence of these blocks is testified by abrupt thickness changes in Rotzo Formation. This created a structural framework favourable to the formation of syn-sedimentary extensional traps (with the Loppio Oolitic Limestone as reservoir and Rotzo Formation as seal). In the Tertiary, Alpine compressional tectonics caused the reactivation of the Jurassic faults with a strike slip kinematics and was associated with the circulation of dolomitizing fluids. The combination of these events led to the formation of secondary fault-related dolomitized bodies. The enhanced pore network in correspondence of the dolomitized dykes

  10. Reservoir evaluation of thin-bedded turbidites and hydrocarbon pore thickness estimation for an accurate quantification of resource

    Science.gov (United States)

    Omoniyi, Bayonle; Stow, Dorrik

    2016-04-01

    One of the major challenges in the assessment of and production from turbidite reservoirs is to take full account of thin and medium-bedded turbidites (succession, they can go unnoticed by conventional analysis and so negatively impact on reserve estimation, particularly in fields producing from prolific thick-bedded turbidite reservoirs. Field development plans often take little note of such thin beds, which are therefore bypassed by mainstream production. In fact, the trapped and bypassed fluids can be vital where maximising field value and optimising production are key business drivers. We have studied in detail, a succession of thin-bedded turbidites associated with thicker-bedded reservoir facies in the North Brae Field, UKCS, using a combination of conventional logs and cores to assess the significance of thin-bedded turbidites in computing hydrocarbon pore thickness (HPT). This quantity, being an indirect measure of thickness, is critical for an accurate estimation of original-oil-in-place (OOIP). By using a combination of conventional and unconventional logging analysis techniques, we obtain three different results for the reservoir intervals studied. These results include estimated net sand thickness, average sand thickness, and their distribution trend within a 3D structural grid. The net sand thickness varies from 205 to 380 ft, and HPT ranges from 21.53 to 39.90 ft. We observe that an integrated approach (neutron-density cross plots conditioned to cores) to HPT quantification reduces the associated uncertainties significantly, resulting in estimation of 96% of actual HPT. Further work will focus on assessing the 3D dynamic connectivity of the low-pay sands with the surrounding thick-bedded turbidite facies.

  11. Impact of rock salt creep law choice on subsidence calculations for hydrocarbon reservoirs overlain by evaporite caprocks

    Science.gov (United States)

    Marketos, G.; Spiers, C. J.; Govers, R.

    2016-06-01

    Accurate forward modeling of surface subsidence above producing hydrocarbons reservoirs requires an understanding of the mechanisms determining how ground deformation and subsidence evolve. Here we focus entirely on rock salt, which overlies a large number of reservoirs worldwide, and specifically on the role of creep of rock salt caprocks in response to production-induced differential stresses. We start by discussing available rock salt creep flow laws. We then present the subsidence evolution above an axisymmetric finite element representation of a generic reservoir that extends over a few kilometers and explore the effects of rock salt flow law choice on the subsidence response. We find that if rock salt creep is linear, as appropriate for steady state flow by pressure solution, the subsidence response to any pressure reduction history contains two distinct components, one that leads to the subsidence bowl becoming narrower and deeper and one that leads to subsidence rebound and becomes dominant at later stages. This subsidence rebound becomes inhibited if rock salt deforms purely through steady state power law creep at low stresses. We also show that an approximate representation of transient creep leads to relatively small differences in subsidence predictions. Most importantly, the results confirm that rock salt flow must be modeled accurately if good subsidence predictions are required. However, in practice, large uncertainties exist in the creep behavior of rock salt, especially at low stresses. These are a consequence of the spatial variability of rock salt physical properties, which is practically impossible to constrain. A conclusion therefore is that modelers can only resort to calculating bounds for the subsidence evolution above producing rock salt-capped reservoirs.

  12. Maximization of wave motion within a hydrocarbon reservoir for wave-based enhanced oil recovery

    KAUST Repository

    Jeong, C.

    2015-05-01

    © 2015 Elsevier B.V. We discuss a systematic methodology for investigating the feasibility of mobilizing oil droplets trapped within the pore space of a target reservoir region by optimally directing wave energy to the region of interest. The motivation stems from field and laboratory observations, which have provided sufficient evidence suggesting that wave-based reservoir stimulation could lead to economically viable oil recovery.Using controlled active surface wave sources, we first describe the mathematical framework necessary for identifying optimal wave source signals that can maximize a desired motion metric (kinetic energy, particle acceleration, etc.) at the target region of interest. We use the apparatus of partial-differential-equation (PDE)-constrained optimization to formulate the associated inverse-source problem, and deploy state-of-the-art numerical wave simulation tools to resolve numerically the associated discrete inverse problem.Numerical experiments with a synthetic subsurface model featuring a shallow reservoir show that the optimizer converges to wave source signals capable of maximizing the motion within the reservoir. The spectra of the wave sources are dominated by the amplification frequencies of the formation. We also show that wave energy could be focused within the target reservoir area, while simultaneously minimizing the disturbance to neighboring formations - a concept that can also be exploited in fracking operations.Lastly, we compare the results of our numerical experiments conducted at the reservoir scale, with results obtained from semi-analytical studies at the granular level, to conclude that, in the case of shallow targets, the optimized wave sources are likely to mobilize trapped oil droplets, and thus enhance oil recovery.

  13. Formation of abnormal high pressure and its application in the study of oil-bearing property of lithologic hydrocarbon reservoirs in the Dongying Sag

    Institute of Scientific and Technical Information of China (English)

    ZHANG ShanWen; ZHANG LinYe; ZHANG ShouChun; LIU Qing; ZHU RiFang; BAO YouShu

    2009-01-01

    The mechanisms of abnormal high pressures are studied in this paper, and it is concluded that the undercompaction, hydrocarbon generation and stratum denudation are obviously effective to fluid pressure buildup. Because of the episodic difference, the hydrocarbon generation and stratum denu-dation are the main factors influencing oil-gas migration. On the basis of basin evolutionary analysis in the Dongying Sag, it is considered that the undercompaction mainly caused the abnormal pressure before the first denudation by the uplift in Late Paleogene, while hydrocarbon generation was the main factor of abnormal pressure after the denudation. The second denudation occurred in Late Neogene, which changed the pressure field and induced the fluid migration. The development of overpressures is the necessary condition to the formation of lithologic hydrocarbon reservoirs, which have positive correlations to overpressures. According to the fullness of the present reservoirs, the quantitative re-lations between oil-bearing property and driving forces of reservoir formation were determined, the latter were decided by dynamic source, reservoir capillary pressure, fluid pressure of surrounding rocks and the dynamic attenuation in different conducting systems.

  14. Reservoir

    Directory of Open Access Journals (Sweden)

    M. Mokhtar

    2016-12-01

    Full Text Available Scarab field is an analog for the deep marine slope channels in Nile Delta of Egypt. It is one of the Pliocene reservoirs in West delta deep marine concession. Channel-1 and channel-2 are considered as main channels of Scarab field. FMI log is used for facies classification and description of the channel subsequences. Core data analysis is integrated with FMI to confirm the lithologic response and used as well for describing the reservoir with high resolution. A detailed description of four wells penetrated through both channels lead to define channel sequences. Some of these sequences are widely extended within the field under study exhibiting a good correlation between the wells. Other sequences were of local distribution. Lithologic sequences are characterized mainly by fining upward in Vshale logs. The repetition of these sequences reflects the stacking pattern and high heterogeneity of the sandstone reservoir. It also refers to the sea level fluctuation which has a direct influence to the facies change. In terms of integration of the previously described sequences with a high resolution seismic data a depositional model has been established. The model defines different stages of the channel using Scarab-2 well as an ideal analog.

  15. [Distribution of various polycyclic aromatic hydrocarbons in reservoir water of Estonia].

    Science.gov (United States)

    Veldre, I A; Itra, A R; Paal'me, L P; Urbas, E R

    1985-01-01

    The paper presents experimental data on different polycyclic aromatic hydrocarbons (PAH) in water, bottom sediments and algae as well as evidence available in literature on their content in exhausts of automobiles, oil shale industry and power station. Attempts are made to reveal differences in sources of the environment pollution with allowance for different PAH/benzo(a)pyrene percentage ratio, but as the PAH ratios are relatively similar in different pollution sources this attempt was a failure.

  16. Hydrocarbon sources and stages of reservoir formation in Kuqa depression, Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Kuqa depression bears not only plenty of natural gas, but also a large amount of condensate and smallquantity of crude oil. Based on the geochemical correlationbetween the Jurassic and Triassic terrestrial hydrocarbonsource rock, this paper confirms that the natural gas in Kuqadepression belongs to coal-type gas and the main gas sourcerock is attributed to the middle to lower Jurassic coal seriesformation, while the main oil source rock is the upper Tri-assic lacustrine mudstone. The authors indicated that Kuqadepression was slowly subsided in Mesozoic, but rapidlywent down in Late Tertiary, which made the Jurassic and Triassic source rock suddenly deep-buried and rapidlyevolved to high and over-mature phase since 5 Ma. The Triassic source rock is postponed to the Early Miocene dur-ing 23-12 Ma when entering the oil-generating peak, whilethe Jurassic is suspended to the latest 5 Ma, especially since2.5 Ma to the dry gas-generating period, which is one of thecharacteristics of the source rock thermal evolution in Kuqadepression. This paper presents a two-stage trapping andlate gas trapping model in Kuqa depression whose charac-teristics are: The main oil and gas reservoirs have differentsources. The oil reservoir is formed early while the gas reservoir is formed lately. During the early stage, it, mainly as oil, takes long distance lateral migration, while in the later stage, it, mainly as gas, takes the vertical migration and also has lateral migration. The trap formed in different time on the south and north sides of the depression and evolved into a distributional pattern with oil in the south part and gas in the north, also oil on the outer ring and gas on the inner ring. This paper points out that the late trapping of the natural gas in Kuqa depression is favorable for the preservation of large gas fields.

  17. Rock physics modeling of heterogeneous carbonate reservoirs:porosity estimation and hydrocarbon detection

    Institute of Scientific and Technical Information of China (English)

    Yu Hao; Ba Jing; Carcione Jose; Li Jin-Song; Tang Gang; Zhang Xing-Yang; He Xin-Zhen; Ouyang Hua

    2014-01-01

    In heterogeneous natural gas reservoirs, gas is generally present as small patch-like pockets embedded in the water-saturated host matrix. This type of heterogeneity, also called“patchy saturation”, causes significant seismic velocity dispersion and attenuation. To establish the relation between seismic response and type of fluids, we designed a rock physics model for carbonates. First, we performed CT scanning and analysis of the fluid distribution in the partially saturated rocks. Then, we predicted the quantitative relation between the wave response at different frequency ranges and the basic lithological properties and pore fluids. A rock physics template was constructed based on thin section analysis of pore structures and seismic inversion. This approach was applied to the limestone gas reservoirs of the right bank block of the Amu Darya River. Based on poststack wave impedance and prestack elastic parameter inversions, the seismic data were used to estimate rock porosity and gas saturation. The model results were in good agreement with the production regime of the wells.

  18. Lithofacies Architecturing and Hydrocarbon Reservoir Potential of Lumshiwal Formation: Surghar Range, Trans-Indus Ranges, North Pakistan

    Directory of Open Access Journals (Sweden)

    Iftikhar Alam

    2015-12-01

    directed Paleo-current system prevailed during deposition of Lumshiwal Formation. Diagenetic and tectonically induced fractures make the formation exceedingly porous and permeable as suitable reservoir horizon for the accumulation of hydrocarbon in the Trans-Indus ranges. The same formation has already been proven as potential reservoir horizon for hydrocarbon in the Kohat Plateau of northwest Pakistan. Secondly, the formation is dominantly comprised of silica/quartz sandstone (quartzarenite which can be used as silica sand, one of the essential raw materials for glass industries. The formation is also comprised of local coal seams which can be mined for production of coal in the region.

  19. Global prediction of continuous hydrocarbon accumulations in self-sourced reservoirs

    Science.gov (United States)

    Eoff, Jennifer D.

    2012-01-01

    This report was first presented as an abstract in poster format at the American Association of Petroleum Geologists (AAPG) 2012 Annual Convention and Exhibition, April 22-25, Long Beach, Calif., as Search and Discovery Article no. 90142. Shale resource plays occur in predictable tectonic settings within similar orders of magnitude of eustatic events. A conceptual model for predicting the presence of resource-quality shales is essential for evaluating components of continuous petroleum systems. Basin geometry often distinguishes self-sourced resource plays from conventional plays. Intracratonic or intrashelf foreland basins at active margins are the predominant depositional settings among those explored for the development of self-sourced continuous accumulations, whereas source rocks associated with conventional accumulations typically were deposited in rifted passive margin settings (or other cratonic environments). Generally, the former are associated with the assembly of supercontinents, and the latter often resulted during or subsequent to the breakup of landmasses. Spreading rates, climate, and eustasy are influenced by these global tectonic events, such that deposition of self-sourced reservoirs occurred during periods characterized by rapid plate reconfiguration, predominantly greenhouse climate conditions, and in areas adjacent to extensive carbonate sedimentation. Combined tectonic histories, eustatic curves, and paleogeographic reconstructions may be useful in global predictions of organic-rich shale accumulations suitable for continuous resource development. Accumulation of marine organic material is attributed to upwellings that enhance productivity and oxygen-minimum bottom waters that prevent destruction of organic matter. The accumulation of potential self-sourced resources can be attributed to slow sedimentation rates in rapidly subsiding (incipient, flexural) foreland basins, while flooding of adjacent carbonate platforms and other cratonic highs

  20. Breakdown of doublet recirculation and direct line drives by far-field flow in reservoirs: implications for geothermal and hydrocarbon well placement

    Science.gov (United States)

    Weijermars, R.; van Harmelen, A.

    2016-07-01

    An important real world application of doublet flow occurs in well design of both geothermal and hydrocarbon reservoirs. A guiding principle for fluid management of injection and extraction wells is that mass balance is commonly assumed between the injected and produced fluid. Because the doublets are considered closed loops, the injection fluid is assumed to eventually reach the producer well and all the produced fluid ideally comes from stream tubes connected to the injector of the well pair making up the doublet. We show that when an aquifer background flow occurs, doublets will rarely retain closed loops of fluid recirculation. When the far-field flow rate increases relative to the doublet's strength, the area occupied by the doublet will diminish and eventually vanishes. Alternatively, rather than using a single injector (source) and single producer (sink), a linear array of multiple injectors separated by some distance from a parallel array of producers can be used in geothermal energy projects as well as in waterflooding of hydrocarbon reservoirs. Fluid flow in such an arrangement of parallel source-sink arrays is shown to be macroscopically equivalent to that of a line doublet. Again, any far-field flow that is strong enough will breach through the line doublet, which then splits into two vortices. Apart from fundamental insight into elementary flow dynamics, our new results provide practical clues that may contribute to improve the planning and design of doublets and direct line drives commonly used for flow management of groundwater, geothermal and hydrocarbon reservoirs.

  1. Invasion of geothermal fluids into hydrocarbon reservoirs; La invasion de fluidos geotermicos en yacimientos de hidrocarburos

    Energy Technology Data Exchange (ETDEWEB)

    Suarez Arriaga, Mario Cesar [Universidad Michoacana, Facultad de Ciencias, Morelia, Michoacan (Mexico)]. E-mail: msuarez@umich.mx

    2009-01-15

    Oil reservoirs beneath the coast of the Gulf of Mexico contain geothermal brine at 150 degrees Celsius and produce a mixture of hot brine and oil. Water from an aquifer 6000 m deep flows vertically through conductive faults. These nonisothermal conditions affect the effective saturations and the relative permeability of the immiscible phases. Dynamic viscosities of oil and water diminish, affecting the displacement of both fluids. Studied wells produce from the oil-saturated zone above the aquifer, yet the total volume of produced water can equal or exceed the volume of oil. The presence of water is a severe problem. We produced an original numerical model able to predict the critical production when the wells start to be invaded by geothermal brine. The model has a single equation in partial derivatives, of a parabolic and nonlineal type, which is a function of water saturation, three-dimension space and time. A gas phase can be included in the model. This equation is a generalization of the classic isothermal result of Buckley-Leverett, in a single dimension. The model is solved numerically by using the Finite Element method on a nonstructured network. The historic effect of water invasion observed in some critical cases is reproduced. After production with both phases stable, a sudden brine invasion can occur with a sharp reduction of the oil volume produced. The immediate objective is to optimize the production so the well will be able to produce a stable water-oil mix where oil always prevails. [Spanish] Se reportan reservorios de aceite situados en la costa del Golfo de Mexico que son invadidos por salmuera geotermica con una temperatura de 150 grados centigrados, produciendo una mezcla variable de agua caliente y aceite. El agua de un acuifero, a 6000 metros de profundidad, fluye verticalmente por fallas conductivas. Estas condiciones no isotermicas afectan las saturaciones efectivas y las permeabilidades relativas de las fases inmiscibles. Las viscosidades

  2. Jurassic and Cretaceous clays of the northern and central North Sea hydrocarbon reservoirs reviewed

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, M.; Haszeldine, R.S.; Fallick, A.E.

    2006-03-15

    illite occurs almost ubiquitously within the clastic sediments of the North Sea. An early pore-lining phase has been interpreted as both infiltrated clastic clay, and as an early diagenetic phase. Early clays may have been quite smectite-rich illites, or even discrete smectites. Later, fibrous illite is undoubtedly neoformed, and can degrade reservoir quality significantly. Both within sandstones and shales, there is an apparent increase in the K content deeper than 4 km of burial, which could be due to dilution of the early smectite-rich phase by new growth illite, or to the progressive illitization of existing I-S. Much of the 'illite' that has been dated by the K-Ar method may therefore actually be I-S. The factors that control the formation of fibrous illite are only poorly known, though temperature must play a role. Illite growth has been proposed for almost the entire range of diagenetic temperatures (e.g. 15-20{sup o}C, Brent Group; 35-40{sup o}C, Oxfordian Sand, Inner Moray Firth; 50-90{sup o}C, Brae formation; 100-110{sup o}C, Brent Group; 130-140{sup o}C, Haltenbanken). It seems unlikely that there is a threshold temperature below which illite growth is impossible (or too slow to be significant), though this is a recurring hypothesis in the literature. Instead, illite growth seems to be an event, commonly triggered by oil emplacement or another change in the physiochemical conditions within the sandstone, such as an episode of overpressure release. Hence fibrous illite can grow at any temperature encountered during diagenesis. Although there is an extensive dataset of K-Ar ages of authigenic illites from the Jurassic of the North Sea, there is no consensus as to whether the data are meaningful, or whether the purified illite samples prepared for analysis are so contaminated with detrital phases as to render the age data meaningless. At present it is unclear about how to resolve this problem, though there is some indication that chemical micro

  3. Research of volcanic reservoir characters and hydrocarbon accumulation models%火山岩储层特征与油气成藏模式研究

    Institute of Scientific and Technical Information of China (English)

    王伟锋; 高斌; 卫平生; 潘建国; 李飞; 易泽军

    2012-01-01

    The history of volcanic reservoir exploration has been already 120 years, after the three development stages which are the accident found, the initial exploration and in-depth study, volcanic rocks have been important areas from the restricted area in the oil and gas exploration. Although volcanic reservoir is in a small proportion of the total oil and gas reservoirs in the world, volcanic reservoir has shown good prospects, and been the new growth point, attracted more and more attention in oil and gas exploration sector. Researching volcanic reservoir, the most important issue is the lithologies and facies. In this article, domestic and foreign classification schemes of volcanic facies is listed,and volcanic reservoir space has been divided into original porosity, original cracks, induced porosity and induced cracks four categories, 13 small classes. The accumulation mode of volcanic reservoir has been divided into lithological accumulation mode, structural accumulation model, structural-lithological accumulation model, weathering crust accumulation mode. There are four key reservoir -forming factors of volcanic reservoirs: structural conditions control the volcanic activities that decide the distribution of volcanic rocks and structural movement can improve reservoir performance immensely; volcanic lithologies and volcanic facies controls the types of reservoir space and development degree of the fractures; space- time matching condition between reservoir formation and hydrocarbon expulsion is the key factor; weathering leaching play an important role on making better the reservoir space. Gravity prospecting and magnetic prospecting are taken much count at home and abroad owing to the characteristics of volcanic rocks on density and magnetic aspects. In volcanic reservoir interpretation, forward modeling,seismic attributes analysis, wave impedance inversion and coherence analysis are the most popular and useful techniques. For the complexity of volcanic

  4. Spatial distribution and sources of polycyclic aromatic hydrocarbons (PAHs) in the reservoir sediments after impoundment of Manwan Dam in the middle of Lancang River, China.

    Science.gov (United States)

    An, NanNan; Liu, Shiliang; Yin, Yijie; Cheng, Fangyan; Dong, Shikui; Wu, Xiaoyu

    2016-08-01

    Polycyclic aromatic hydrocarbons (PAHs) have received increasing attentions owing to their carcinogenicity, teratogenicity and environmental toxicity. The studies on the spatial variations, sources identification and potential ecological risk assessment of PAHs in the reservoir sediments after dam construction are becoming new hotpots. Sixteen PAHs contamination levels were investigated from 15 sample sections in the sediments of Manwan Reservoir in the middle of Lancang River, China. Total concentrations of 16 PAHs ranged from 14.4 to 137.7 ng g(-1) dw with a mean concentration of 70.68 ng g(-1) dw. The areas with residential settlement at large tributaries and near dam had higher PAHs concentrations. In the sight of classification of PAHs pollution levels, the sediments of Manwan Reservoir could be considered as low to moderate PAHs polluted levels. One-way analysis of variance for spatial analysis revealed that there were no significant differences (P PAHs at the reservoir head, centre and tail. Moreover, no significant differences (P PAH at the mainstream and tributaries except that BaP showed significant differences (P PAHs in Manwan Reservoir might be mixed, primarily including the petroleum source and coal combustion. As compared with sediment quality guidelines, the observed concentrations of PAHs in all sample sections did not exceed the effects range low (ERL) and the threshold effect level (TEL) values, suggesting that there were little harmful biological toxic effects on the aquatic organisms in Manwan Reservoir. The study provided a comprehensive overview on the PAHs contaminations on the reservoir sediments in the middle Lancang River, which may have an important significances on the international river management.

  5. The coupling of dynamics and permeability in the hydrocarbon accumulation period controls the oil-bearing potential of low permeability reservoirs: a case study of the low permeability turbidite reservoirs in the middle part of the third member of Shahejie Formation in Dongying Sag

    DEFF Research Database (Denmark)

    Yang, Tian; Cao, Ying-Chang; Wang, Yan-Zhong

    2016-01-01

    The relationships between permeability and dynamics in hydrocarbon accumulation determine oilbearing potential (the potential oil charge) of low permeability reservoirs. The evolution of porosity and permeability of low permeability turbidite reservoirs of the middle part of the third member of t...

  6. 中国深层油气成藏条件与勘探潜力%Hydrocarbon accumulation conditions and exploration potential of deep reservoirs in China

    Institute of Scientific and Technical Information of China (English)

    朱光有; 张水昌

    2009-01-01

    With the development of drilling techniques and oil-gas exploration, deep hydrocarbon exploration has gained more and more attention and may become an important fungible field for rising reserves. Analysis on the data of drilling and oil-gas geology of deep wells over 7000m in depth shows that the low limit of depth range for generation of deep hydrocarbon is possibly large, and there still exists the hydrocarbon-generation potential for the high mature source rocks. The low limit of preservation depth for the effective reservoir can shift downward, and the fractured reservoir is predominant. The oil-gas pools mainly include the earlier accu-mulation-later deep burying pattern, the later accumulation pattern after deeply burying and the multi-stage charging pattern. The earlier accumulation pattern can restrain the shrink of rock porosity during the deep burying process. The fractured reservoir is pre-dominant and more developed near the fault belts, when the burial depth is more than 6000m. Faults connected with the deep source rocks are usually the important migration pathways for the later oil accumulation. The hydrocarbon enrichment degree near the fault belts is very high. The multi-stage hydrocarbon charging and strong charging processes can often improve the reserve abundance. The hydrocarbon resource in the strata beyond 7000 m in depth is of considerable potential in the basins in central and western China.%随着油气钻探技术的提高和勘探工作的不断深入,深层油气勘探愈来愈被重视,深层将可能成为未来储量增长的重要接替领域.对中国7000m以下深井的钻探资料和深层油气地质资料分析表明,烃源岩的生烃深度下限范围可能较大,高过熟阶段的烃源岩生烃潜力依然存在.深部各类有效储集体的保存深度下限可能下移,以发育裂缝型储集体为主,油气藏类型主要包括早期成藏-后期深埋型、储层深埋后晚期成藏型和多期充注成藏型.早期

  7. A Spatial-Spectral Approach for Visualization of Vegetation Stress Resulting from Pipeline Leakage.

    Science.gov (United States)

    Van derWerff, Harald; Van der Meijde, Mark; Jansma, Fokke; Van der Meer, Freek; Groothuis, Gert Jan

    2008-06-04

    Hydrocarbon leakage into the environment has large economic and environmental impact. Traditional methods for investigating seepages and their resulting pollution, such as drilling, are destructive, time consuming and expensive. Remote sensing is an efficient tool that offers a non-destructive investigation method. Optical remote sensing has been extensively tested for exploration of onshore hydrocarbon reservoirs and detection of hydrocarbons at the Earth's surface. In this research, we investigate indirect manifestations of pipeline leakage by way of visualizing vegetation anomalies in airborne hyperspectral imagery. Agricultural land-use causes a heterogeneous landcover; variation in red edge position between fields was much larger than infield red edge position variation that could be related to hydrocarbon pollution. A moving and growing kernel procedure was developed to normalzie red edge values relative to values of neighbouring pixels to enhance pollution related anomalies in the image. Comparison of the spatial distribution of anomalies with geochemical data obtained by drilling showed that 8 out of 10 polluted sites were predicted correctly while 2 out of 30 sites that were predicted clean were actually polluted.

  8. A Spatial-Spectral Approach for Visualization of Vegetation Stress Resulting from Pipeline Leakage

    Directory of Open Access Journals (Sweden)

    Gert Jan Groothuis

    2008-06-01

    Full Text Available Hydrocarbon leakage into the environment has large economic and environmental impact. Traditional methods for investigating seepages and their resulting pollution, such as drilling, are destructive, time consuming and expensive. Remote sensing is an efficient tool that offers a non-destructive investigation method. Optical remote sensing has been extensively tested for exploration of onshore hydrocarbon reservoirs and detection of hydrocarbons at the Earth’s surface. In this research, we investigate indirect manifestations of pipeline leakage by way of visualizing vegetation anomalies in airborne hyperspectral imagery. Agricultural land-use causes a heterogeneous landcover; variation in red edge position between fields was much larger than infield red edge position variation that could be related to hydrocarbon pollution. A moving and growing kernel procedure was developed to normalzie red edge values relative to values of neighbouring pixels to enhance pollution related anomalies in the image. Comparison of the spatial distribution of anomalies with geochemical data obtained by drilling showed that 8 out of 10 polluted sites were predicted correctly while 2 out of 30 sites that were predicted clean were actually polluted.

  9. Controls on hydrocarbon occurrence and productivity in the F6 reservoir, Tin Fouye-Tabankort area, NW Illizi Basin

    Energy Technology Data Exchange (ETDEWEB)

    Alem, N.; Assassi, S.; Benhebouche, S.; Kadi, B. [CDR-Sonatrach, Boumerdes (Algeria)

    1998-12-31

    Several oil accumulations of various sizes have been found within the F6 reservoir of Upper Silurian-Lower Devonian age in the Tin Fouye region of the Illizi Basin, about 1500 km from Algiers. Lithologically, the F6 consists of interbedded sandstones and shales and is subdivided into units: M1, M2, A, B1, B2, C1, C2 and C3, the upper units often being missing through erosion. These reservoirs, which were deposited in offshore coastal bars and tidal channels, show a high degree of lateral and vertical facies variation. Study of the hydrology of the F6 reservoir shows that connate water and oil have been frequently flushed by fresh water in the most permeable units, particularly C1 and B2. This finding is supported by hydrochemical data, by the inclination of oil-water contacts and by a high observed hydraulic gradient. (author)

  10. 纳米油气与源储共生型油气聚集%Nano-hydrocarbon and the accumulation in coexisting source and reservoir

    Institute of Scientific and Technical Information of China (English)

    邹才能; 高晓辉; 贾进华; 郭秋麟; 白斌; 杨智; 陶士振; 李伟; 吴松涛; 侯连华; 朱如凯; 袁选俊; 王岚

    2012-01-01

    在对比非常规油气与常规油气类型、地质特征及勘探技术的基础上,提出“纳米油气”的概念,指出“纳米油气”是未来石油工业的发展方向.纳米油气是指用纳米技术研究和开采聚集在纳米级孔喉储集系统中的油气,纳米油气主要分布在烃源岩层及与其大面积紧密接触的近源致密储集层系中,涵盖了页岩油、页岩气、煤层气、致密砂岩油、致密砂岩气、致密灰岩油等,储集层孔喉直径一般为纳米级;油气水在纳米孔喉中渗流能力差,相态分异难,主要依靠超压驱动,油气被滞留吸附,在源储共生致密层系中大面积连续分布.中国含油气盆地发育源储共生型致密层系、碳酸盐岩缝洞层系、火山岩缝洞层系、变质岩裂缝层系等多种类型油气聚集层系,其中源储共生层系油气聚集位于盆地中心或斜坡部位,源内或近源层状大面积聚集,是资源分布的主体和未来发展重点领域.以鄂尔多斯盆地和四川盆地源储共生型油气聚集为典型实例,提出连续型油气“两线一区”(即源储共生层系油气聚集顶底界线、油气连续聚集边界线、“甜点”分布核心区)评价方法.%By comparison of the types, geological characteristics and exploration technologies of conventional and unconventional hydrocarbon, this paper proposes the concept of "nano-hydrocarbon" and indicates that "nano-hydrocarbon" is the development direction of oil and gas indushy in the future. Nano-hydrocarbon refers to the research and production, by nano-technology, of oil and gas accumulated in the reservoir system of nano-sized pore-throats. It is mainly distributed in source rocks and the neighbouring tight reservoirs and includes shale oil, shale gas, coal-bed methane, tight sandstone oil & gas, tight limestone oil and so on, with nano-sized diameter of pore-throats in reservoirs. Oil, gas and water in nano-sized pore-throats exhibit poor

  11. On Probability Leakage

    OpenAIRE

    Briggs, William M.

    2012-01-01

    The probability leakage of model M with respect to evidence E is defined. Probability leakage is a kind of model error. It occurs when M implies that events $y$, which are impossible given E, have positive probability. Leakage does not imply model falsification. Models with probability leakage cannot be calibrated empirically. Regression models, which are ubiquitous in statistical practice, often evince probability leakage.

  12. Controlling of Hydrocarbons Expulsion of Source Rock on Buried Hill Hydrocarbon Reservoir in Nanpu Depression by Acoustic Logging Methodology%测井-地化结合法探讨南堡凹陷潜山源控藏作用

    Institute of Scientific and Technical Information of China (English)

    董月霞; 李素梅; 陈安定; 王政军; 张鹏; 陈君

    2015-01-01

    Industrial petroleum was discovered from Palaeozoic deep horizons in the Nanpu Depression,Bohai Bay Basin,which suggests significant deep petroleum potential in the area.One of the issues in exploration is forecasting favorable place for prospecting in the area.Hydrocarbons expulsion downward from the source rocks immediately overlapped buried hill should be useful in this aspect.Acoustic logging combined with geochemical approaches was utilized in this study to identify hydrocarbons expulsion and evaluate hydrocarbon potential.Af-ter a detailed correlative acoustic logging and geochemical study,a combined hydrocarbons expulsion model of the source rocks in the Nanpu Depression was established,which was used to investigate hydrocarbons expulsion of the source rocks from 33 wells in the Nanpu Depression.The results suggest that the average depths of the source rocks with the hydrocarbons expelled downward into the burial hill in the No.2 and 3 Tectonic Belts are about 248 m and 358 m,respectively,and only 35 m for the No.1 Tectonic Belt.No obvious hydrocarbons ex-pulsion into burial hill was observed in the No.4 and 5 Tectonic Belts in the depression.This result coincides with the hydrocarbons discovered up to now in the burial hills.We suggest that these factors including contact style between the source rock and the burial hill,the position of the hydrocarbon kitchen,the thermal maturity of the source rocks,the volcanic rock acting as barrier bed and faults developed,have a controlling of the amounts and characteristics of the hydrocarbons expelled by the source rocks and charged into the burial hill in the Nanpu Depression.A comprehensive study of hydrocarbons expulsion,migration and accumulation indicate that the No.2 and 3 Tectonic Belts and next the No.1 Tectonic Belt are prospective areas with burial hill hydro-carbons reservoir developed.This study also indicated that acoustic logging could be an important tool identif-ying hydrocarbons expulsion and would

  13. Human Health and Ecological Risk Assessment of 16 Polycyclic Aromatic Hydrocarbons in Drinking Source Water from a Large Mixed-Use Reservoir.

    Science.gov (United States)

    Sun, Caiyun; Zhang, Jiquan; Ma, Qiyun; Chen, Yanan

    2015-10-30

    Reservoirs play an important role in living water supply and irrigation of farmlands, thus the water quality is closely related to public health. However, studies regarding human health and ecological risk assessment of polycyclic aromatic hydrocarbons (PAHs) in the waters of reservoirs are very few. In this study, Shitou Koumen Reservoir which supplies drinking water to 8 million people was investigated. Sixteen priority PAHs were analyzed in a total of 12 water samples. In terms of the individual PAHs, the average concentration of Fla, which was 5.66 × 10(-1) μg/L, was the highest, while dibenz(a,h)anthracene which was undetected in any of the water samples was the lowest. Among three PAH compositional patterns, the concentration of low-molecular-weight and 4-ring PAHs was dominant, accounting for 94%, and the concentration of the total of 16 PAHs was elevated in constructed-wetland and fish-farming areas. According to the calculated risk quotients, little or no adverse effects were posed by individual and complex PAHs in the water on the aquatic ecosystem. In addition, the results of hazard quotients for non-carcinogenic risk also showed little or no negative impacts on the health of local residents. However, it could be concluded from the carcinogenic risk results that chrysene and complex PAHs in water might pose a potential carcinogenic risk to local residents. Moreover, the possible sources of PAHs were identified as oil spills and vehicular emissions, as well as the burning of biomass and coal.

  14. Geologic Storage of CO2: Leakage Pathways and Environmental Risks

    Science.gov (United States)

    Celia, M. A.; Peters, C. A.; Bachu, S.

    2002-05-01

    Geologic storage of CO2 appears to be an attractive option for carbon mitigation because it offers sufficient capacity to solve the problem, and it can be implemented with existing technology. Among the list of options for storage sites, depleted hydrocarbon reservoirs and deep saline aquifers are two major categories. While injection into hydrocarbon reservoirs offers immediate possibilities, especially in the context of enhanced oil recovery, it appears that deep saline aquifers provide the extensive capacity necessary to solve the problem over the decade to century time scale. Capacity and technology argue favorably for this option, but remaining obstacles to implementation include capture technologies, overall economic considerations, and potential environmental consequences of the injection. Of these, the environmental questions may be most difficult to solve. Experience from CO2 floods for enhanced oil recovery and from CO2 and acid gas disposal operations indicates that geological storage of CO2 is safe over the short term for comparatively small amounts of CO2. However, there is no experience to date regarding the long-term fate and safety of the large volumes of CO2 that must be injected to significantly reduce atmospheric emissions. In order to make proper evaluation of environmental risks, the full range of possible environmental consequences must be considered. Most of these environmental concerns involve migration and leakage of CO2 into shallow portions of the subsurface and eventually into the atmosphere. In shallow subsurface zones, elevated levels of carbon dioxide can cause pH changes, leading to possible mobilization of ground-water contaminants including metals. In the unsaturated zone, vegetation can be adversely affected, as can other ecosystem components. At the land surface, elevated levels of CO2 can lead to asphyxiation in humans and other animals. And finally, in the atmosphere, CO2 that leaks from underground diminishes the effectiveness

  15. [Identification of Hydrocarbon-Oxidizing Dietzia Bacteria from Petroleum Reservoirs Based on Phenotypic Properties and Analysis of the 16S rRNA and gyrB Genes].

    Science.gov (United States)

    Nazina, T N; Shumkova, E S; Sokolova, D Sh; Babich, T L; Zhurina, M V; Xue, Yan-Fen; Osipov, G A; Poltaraus, A B; Tourova, T P

    2015-01-01

    The taxonomic position of hydrocarbon-oxidizing bacterial strains 263 and 32d isolated from formation water of the Daqing petroleum reservoir (PRC) was determined by polyphasic taxonomy techniques, including analysis of the 16S rRNA and the gyrB genes. The major chemotaxonomic characteristics of both strains, including the IV type cell wall, composition of cell wall fatty acids, mycolic acids, and menaquinones, agreed with those typical of Dietzia strains. The DNA G+C content of strains 263 and 32d were 67.8 and 67.6 mol%, respectively. Phylogenetic analysis of the 16S rRNA gene of strain 32d revealed 99.7% similarity to the gene of D. maris, making it possible to identify strain 32d as belonging to this species. The 16S rRNA gene sequence of strain 263 exhibited 99.7 and 99.9% similarity to those of D. natronolimnaea and D. cercidiphylli YIM65002(T), respectively. Analysis of the gyrB genes of the subterranean isolates and of a number of Dietzia type strains confirmed classiffication of strain 32d as a D. maris strain and of strain 263, as a D. natronolimnaea strain. A conclusion was made concerning higher resolving power of phylogenetic analysis of the gyrB gene compared to the 16S rRNA gene analysis in the case of determination of the species position of Dietzia isolates.

  16. Sequential Extraction on Oil Sandstones from TZ401 Well——A Case Study on Filling History of Hydrocarbon Reservoir

    Institute of Scientific and Technical Information of China (English)

    Pan Changchun; Liu Dayong

    2008-01-01

    Sequential extraction was performed on two oil sandstones from the Upper Carboniferous oil columns of TZ401 well.The free oils of these two oil sandstones and a crude oil from the Lower Carboniferous oil column of this well have low ratios of C28/C27+C28+ C29) steranes and gammacerane/C31 hopanes,ranging of 0.11-0.16 and 0.09-0.15,respectively,similar to those from the Middle-Upper Ordovician source rock.However,these two ratios for the adsorbed and inclusion oils of these two oil sandstones are relatively high,ranging of 0.29-0.31 and 0.26-0.40,respectively,similar to those of the Cambrian-Lower Ordovician source rock.This result demonstrates that the initial oil charging the reservoirs was derived from the Cambrian-Lower Ordovician source rock,whereas the later charging oil was derived from the Middle--Upper Ordovician source rock.

  17. Groundwater-Quality Impacts from Natural-Gas Wellbore Leakage: Numerical Sensitivity Analysis of Hydrogeologic, Geostatistical, and Source-Term Parameterization at Varying Depths

    Science.gov (United States)

    Rice, A. K.; McCray, J. E.; Singha, K.

    2016-12-01

    The development of directional drilling and stimulation of reservoirs by hydraulic fracturing has transformed the energy landscape in the U.S. by making recovery of hydrocarbons from shale formations not only possible but economically viable. Activities associated with hydraulic fracturing present a set of water-quality challenges, including the potential for impaired groundwater quality. In this project, we use a three-dimensional, multiphase, multicomponent numerical model to investigate hydrogeologic conditions that could lead to groundwater contamination from natural gas wellbore leakage. This work explores the fate of methane that enters a well annulus, possibly from an intermediate formation or from the production zone via a flawed cement seal, and leaves the annulus at one of two depths: at the elevation of groundwater or below a freshwater aquifer. The latter leakage scenario is largely ignored in the current scientific literature, where focus has been on leakage directly into freshwater aquifers, despite modern regulations requiring steel casings and cement sheaths at these depths. We perform a three-stage sensitivity analysis, examining (1) hydrogeologic parameters of media surrounding a methane leakage source zone, (2) geostatistical variations in intrinsic permeability, and (3) methane source zone pressurization. Results indicate that in all cases methane reaches groundwater within the first year of leakage. To our knowledge, this is the first study to consider natural gas wellbore leakage in the context of multiphase flow through heterogeneous permeable media; advantages of multiphase modeling include more realistic analysis of methane vapor-phase relative permeability as compared to single-phase models. These results can be used to inform assessment of aquifer vulnerability to hydrocarbon wellbore leakage at varying depths.

  18. Meshwork-carpet type hydrocarbon reservoir transportation system in Junggar Basin%准噶尔盆地网毯式油气成藏输导体系

    Institute of Scientific and Technical Information of China (English)

    刘桠颖; 徐怀民; 姚卫江; 刘楼军

    2011-01-01

    利用输导体地质综合研究方法,以断层、砂体及断—砂组合关系分析为基础,对准噶尔盆地白垩系油气成藏体系进行研究,分析网毯式油气成藏体系输导体的特征及分布.结果表明:按照输导体与毯状仓储层中底砾岩的接触关系,可建立3类9型输导体样式,包括上沟通型、下沟通型、自沟通型、内沟通型断裂输导体,沟通型、未沟通型不整合面输导体,上沟通型、下沟通型、内沟通型砂体连通输导体;不同类型的输导体组合出“Y”型输导模式、“T”型输导模式、“H”型输导模式;输导体在仓储层的“成毯”和“溢散”过程中起到关键作用;复杂的网状输导体系控制了研究区油气藏的形成、分类及分布特征.%Using the the geological comprehensive study method of transportation system, the hydrocarbon accumulation system of Cretaceous in Junggar Basin was studied based on fault, sand body and matching relationship of sand-fault. The characteristics and the spatial distribution of transportation system of meshwork-carpet type hydrocarbon reservoir system were analyzed. The results show that three classes and nine types of conductor department styles are defined according t6 the contact relationship between elements of transportation systems and basal conglomerate of storage layer. It includes upper-connected type, down-connected type, all-connected type and inner-connected type of fault transportation system, connected type and non-connected type of unconformity transportation system as well as upper-connected type, down-connected type and inner-connected type of sand body connected transportation system. Different types of transportation combinations make three transportation models of oil and gas about "Y" type model, "T" type model, and "H" type model. Transportation system plays a key role in the process of making carpet and diffusion in storage layer. Reticular and complex transportation

  19. Variations of the petrophysical properties of rocks with increasing hydrocarbons content and their implications at larger scale: insights from the Majella reservoir (Italy)

    Science.gov (United States)

    Trippetta, Fabio; Ruggieri, Roberta; Lipparini, Lorenzo

    2016-04-01

    Crustal processes such as deformations or faulting are strictly related to the petrophysical properties of involved rocks. These properties depend on mineral composition, fabric, pores and any secondary features such as cracks or infilling material that may have been introduced during the whole diagenetic and tectonic history of the rock. In this work we investigate the role of hydrocarbons (HC) in changing the petrophysical properties of rock by merging laboratory experiments, well data and static models focusing on the carbonate-bearing Majella reservoir. This reservoir represent an interesting analogue for the several oil fields discovered in the subsurface in the region, allowing a comparison of a wide range of geological and geophysical data at different scale. The investigated lithology is made of high porosity ramp calcarenites, structurally slightly affected by a superimposed fracture system and displaced by few major normal faults, with some minor strike-slip movements. Sets of rock specimens were selected in the field and in particular two groups were investigated: 1. clean rocks (without oil) and 2. HC bearing rocks (with different saturations). For both groups, density, porosity, P and S wave velocity, permeability and elastic moduli measurements at increasing confining pressure were conducted on cylindrical specimens at the HP-HT Laboratory of the Istituto Nazionale di Geofisica e Vulcanologia (INGV) in Rome, Italy. For clean samples at ambient pressure, laboratory porosity varies from 10 % up to 26 % and P wave velocity (Vp) spans from 4,1 km/s to 4,9 km/s and a very good correlation between Vp, Vs and porosity is observed. The P wave velocity at 100 MPa of confining pressure, ranges between 4,5 km/s and 5,2 km/s with a pressure independent Vp/Vs ratio of about 1,9. The presence of HC within the samples affects both Vp and Vs. In particular velocities increase with the presence of hydrocarbons proportionally respect to the amount of the filled

  20. Distribution, sources, and risk assessment of polycyclic aromatic hydrocarbons (PAHs) in surface water in industrial affected areas of the Three Gorges Reservoir, China.

    Science.gov (United States)

    Zheng, Binghui; Ma, Yingqun; Qin, Yanwen; Zhang, Lei; Zhao, Yanmin; Cao, Wei; Yang, Chenchen; Han, Chaonan

    2016-12-01

    Water samples were collected from wastewater treatment plant (WWTP), drain water (DW), major tributaries (MT), and main course of the Yangtze River (MY) in areas of three industrial parks (IPs) in Chongqing city in the Three Gorges Reservoir (TGR). Sixteen EPA priority polycyclic aromatic hydrocarbon (PAH) pollutants were quantified to identify the effects of industrial activities on water quality of the TGR. The results showed that 11 individual PAHs were quantified and 5 PAHs (naphthalene (Nap), acenaphthylene (Acy), benzo[k]fluoranthene (BkF), indeno[1,2,3-cd]pyrene (InP), and benzo[g,h,i]perylene (BgP)) were under detection limits in all of the water samples. Three-ring and four-ring PAHs were the most detected PAHs. Concentrations of individual PAHs were in the range of not detected (nd) to 24.3 ng/L. Total PAH concentrations for each site ranged from nd to 42.9 ng/L and were lower compared to those in other studies. The mean PAH concentrations for sites WWTP, DW, MT, and MY showed as follows: DW (25.9 ng/L) > MY (15.5 ng/L) > MT (14.0 ng/L) > WWTP (9.3 ng/L), and DW contains the highest PAH concentrations. Source identification ratios showed that petroleum and combustion of biomass coal and petroleum were the main sources of PAHs. The results of potential ecosystem risk assessment indicated that, although PAH concentrations in MT and MY are likely harmless to ecosystem, contaminations of PAHs in DW were listed as middle levels and some management strategies and remediation actions, like strengthen clean production processes and banning illegal sewage discharging activities, etc., should be taken to lighten the ecosystem risk caused by PAHs especially risks caused by water discharging drains.

  1. Extensive CO2 Leakage From Extinct and Modern CO2 Reservoirs in New Mexico and Arizona: Evaluating the Role of Seal Bypass and Large-Volume Travertine Deposition With Implications For CO2 Sequestration

    Science.gov (United States)

    Priewisch, A.; Crossey, L. J.; Karlstrom, K. E.; Mozley, P.

    2014-12-01

    Quaternary large-volume travertine deposits in New Mexico and Arizona occur along the Rio Grande rift and on the southeastern Colorado Plateau. Travertines are natural analogues for CO2 leakage along fault systems because they form due to the degassing of CO2 from carbonic groundwater that migrates up fault systems. Travertine volumes can be used to infer integrated CO2 leakage along faults, which includes: (1) CO2 that becomes fixed in CaCO3/travertine (tons of carbon converted into tons of carbonate), (2) the amount of CO2 that degassed into the atmosphere (twice the amount of (1), based on reaction stoichiometry), (3) dissolved CO2 that is carried away with the water discharging from a spring (based on modern spring discharge and dissolved carbon content), and (4) CO2 that escapes through the soil (based on modern soil flux measurements). The total CO2 leakage (1 and 2) calculated in this study is estimated as ~6 Gt (gigatons) whereas the integrated CO2 leakage (1-4) is estimated as ~128 Gt over ~450,000 years of travertine accumulation. U-series dating of the travertines shows that the deposits formed episodically which implies that CO2 leakage occurred episodically. Better understanding of integrated CO2 leakage along fault systems is needed to better constrain global estimates of natural CO2 fluxes, and to help in risk assessment of CO2 sequestration sites designed to effectively store anthropogenic CO2 in the subsurface.

  2. Method of detecting leakage from geologic formations used to sequester CO.sub.2

    Science.gov (United States)

    White, Curt; Wells, Arthur; Diehl, J. Rodney; Strazisar, Brian

    2010-04-27

    The invention provides methods for the measurement of carbon dioxide leakage from sequestration reservoirs. Tracer moieties are injected along with carbon dioxide into geological formations. Leakage is monitored by gas chromatographic analyses of absorbents. The invention also provides a process for the early leak detection of possible carbon dioxide leakage from sequestration reservoirs by measuring methane (CH.sub.4), ethane (C.sub.2H.sub.6), propane (C.sub.3H.sub.8), and/or radon (Rn) leakage rates from the reservoirs. The invention further provides a method for branding sequestered carbon dioxide using perfluorcarbon tracers (PFTs) to show ownership.

  3. 塔里木盆地典型砂岩油气储层自生伊利石K-Ar同位素测年研究与成藏年代探讨%K-Ar Dating of Authigenic Illites and Its Applications to the Study of Hydrocarbon Charging Histories of Typical Sandstone Reservoirs in Tarim Basin, China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The Tarim Basin in China comprises eight sets of sandstone reservoirs, five of which are investigated in detail in this study. The main purpose of this study is to investigate the hydrocarbon charging histories of reservoirs by applying K-Ar dating of authigenic illites. The ages of authigenic illites from the Lower Silurian bituminous sandstones in the Central Uplift area range from 383.5 to 235.2 Ma, suggesting that the Silurian oil accumulations were formed from the late Caledonian till the late Hercynian. The ages of authigenic illites from the Upper Devonian Donghe Sandstone reservoirs range from 263.8 to 231.3 Ma, indicating that hydrocarbon accumulations within the Donghe sandstone were formed mainly in the late Hercynian. The authigenic illites ages from the Lower Jurassic Yangxia Group sandstones in the Yinan-2 gas reservoir (Yinan-2, Kuqa Depression) range from 28.1 to 23.9 Ma, suggesting that the initial hydrocarbon charging occurred in the Miocene. The ages of the authigenic illites from the Lower Cretaceous sandstones in the Akemomu gas field (Ake-1, Kashi Sag, Southwest Depression) range from 22.6 to 18.8 Ma, indicating a probable early oil accumulation or early migration of hydrocarbon within this area. The illites from the Paleogene sandstones in the Dina-2 gas reservoir (Dina-201, Kuqa Depression) have a detrital origin; they cannot be used to study the hydrocarbon charging histories. The ages of authigenic illites in the underlying Cretaceous sandstones in the same well (Dina-201)range from 25.5 to 15.5 Ma, indicating that hydrocarbon charging in this reservoir probably occurred within the Miocene.This study highlights the potential of applying K-Ar dating of authigenic illites to investigate the timing of hydrocarbon charging histories of the Tarim Basin reservoir sandstones.

  4. 含油气盆地重要勘探领域——基岩油气藏%Important Exploration Areas in Petaliferous Basins-The Basement Hydrocarbon Reservoirs

    Institute of Scientific and Technical Information of China (English)

    陈文玲; 周文

    2012-01-01

    This paper analyzes domestic and foreign reservoir characters, accumulation factors and distribution of basement reservoir and concludes that basement is formed before basin and distributed in any platforms. There is one basement in simple basin. In superimposed basins there must be a long hiatus or tectonic movement so that they can have both new and old basements. Basement hydrocarbon reservoirs can be divided into two types: the reservoir on top of buried hills and the reservoir inside buried hills. The reservoirs are composed of granite and eruptive rocks, and have particular effective reservoir spaces and have strong heterogeneity. Characteristics of them include that they are early oil generation and late reservoir, early accumulation period and early trap generation. They have various of trap types and migration modes, and have complex inside composition and translocation systems. The world's largest oil and gas reservoirs are located in depression basin, and most Chinese reservoirs distributes in eastern fault basin and in northern flexural basin and old basement of superimposed basins.%通过对国内外基岩油气藏储层特征、成藏要素、分布特征的分析,认为基岩是盆地形成前的地层,任何时期的地台均有分布.简单盆地只有一个基岩,叠合盆地必需有长时间的沉积间断或有过大的构造运动才能有新、老基岩之分.基岩油气藏可以分为潜山顶部基岩油气藏和潜山内幕型基岩油气藏.储集岩以花岗岩和火成岩为主,具有特殊的有效储集空间,非均质性强.基岩油气藏储层具有新生古储、成藏期早、圈闭形成早且类型多、内幕结构复杂、疏导体系复杂、运移方式多等特征.世界大型基岩油气藏多分布在拗陷盆地,中国基岩油气藏重点分布在东部断陷盆地基底和北部褶皱盆地基底以及叠合盆地的老基底中.

  5. P-T封隔器在异常高压低渗透层渗漏原因初探%Exploratory Research on the P-T Pack Leakage Reasons during Pressure Buildup Test in the Abmormal High Pressure Low Permeability Reservoir

    Institute of Scientific and Technical Information of China (English)

    白学东; 耿玉乾; 祁连秋

    2001-01-01

    The P-T pack leakage reasons are pointed out,which are accrued during pressure buildup test in the abnormal high pres sure low penneability reservoir. The calculation formation for determining the highest leakage pressures,and its practica bility is verified by the field examples. The leakage solving methods and measures are given.%用P-T封隔器测试高压低渗透层易发生渗漏,取不到完整的地层资料。经对P-T封隔器 进行井下受力分析,找出了封隔器发生渗漏的原因;给出了确定发生渗漏时最高关井压力的计算公 式并验证了其正确性;提出了解决P-T封隔器渗漏问题的相关措施。

  6. P-T封隔器在异常高压低渗透层渗漏原因初探%Exploratory Research on the P-T Pack Leakage Reasons during Pressure Buildup Test in the Abmormal High Pressure Low Permeability Reservoir

    Institute of Scientific and Technical Information of China (English)

    白学东; 耿玉乾; 祁连秋

    2001-01-01

    The P-T pack leakage reasons are pointed out,which are accruedduring pressure buildup test in the abnormal high pres sure low penneability reservoir. The calculation formation for determining the highest leakage pressures,and its practica bility is verified by the field examples. The leakage solving methods and measures are given.%用P-T封隔器测试高压低渗透层易发生渗漏,取不到完整的地层资料。经对P-T封隔器进行井下受力分析,找出了封隔器发生渗漏的原因;给出了确定发生渗漏时最高关井压力的计算公 式并验证了其正确性;提出了解决P-T封隔器渗漏问题的相关措施。

  7. Land-use Leakage

    Energy Technology Data Exchange (ETDEWEB)

    Calvin, Katherine V.; Edmonds, James A.; Clarke, Leon E.; Bond-Lamberty, Benjamin; Kim, Son H.; Wise, Marshall A.; Thomson, Allison M.; Kyle, G. Page

    2009-12-01

    Leakage occurs whenever actions to mitigate greenhouse gas emissions in one part of the world unleash countervailing forces elsewhere in the world so that reductions in global emissions are less than emissions mitigation in the mitigating region. While many researchers have examined the concept of industrial leakage, land-use policies can also result in leakage. We show that land-use leakage is potentially as large as or larger than industrial leakage. We identify two potential land-use leakage drivers, land-use policies and bioenergy. We distinguish between these two pathways and run numerical experiments for each. We also show that the land-use policy environment exerts a powerful influence on leakage and that under some policy designs leakage can be negative. International “offsets” are a potential mechanism to communicate emissions mitigation beyond the borders of emissions mitigating regions, but in a stabilization regime designed to limit radiative forcing to 3.7 2/m2, this also implies greater emissions mitigation commitments on the part of mitigating regions.

  8. Model for Electromagnetic Information Leakage

    OpenAIRE

    Mao Jian; Li Yongmei; Zhang Jiemin; Liu Jinming

    2013-01-01

    Electromagnetic leakage will happen in working information equipments; it could lead to information leakage. In order to discover the nature of information in electromagnetic leakage, this paper combined electromagnetic theory with information theory as an innovative research method. It outlines a systematic model of electromagnetic information leakage, which theoretically describes the process of information leakage, intercept and reproduction based on electromagnetic radiation, and ana...

  9. Predicting Leakage in Labyrinth Seals

    Science.gov (United States)

    Morrison, G. L.; Rhode, D. L.; Cogan, K. C.; Chi, D.; Demko, J.

    1985-01-01

    Analytical and empirical methods evaluated. 264-page report presents comprehensive information on leakage in labyrinth seals. Summarizes previous analyses of leakage, reviews leakage tests conducted by authors and evaluates various analytical and experimental methods of determining leakage and discusses leakage prediction techniques.

  10. Model for Electromagnetic Information Leakage

    Directory of Open Access Journals (Sweden)

    Mao Jian

    2013-09-01

    Full Text Available Electromagnetic leakage will happen in working information equipments; it could lead to information leakage. In order to discover the nature of information in electromagnetic leakage, this paper combined electromagnetic theory with information theory as an innovative research method. It outlines a systematic model of electromagnetic information leakage, which theoretically describes the process of information leakage, intercept and reproduction based on electromagnetic radiation, and analyzes amount of leakage information with formulas.  

  11. 成因机制控制下低对比度油气层研究方法%Research method of low contrast hydrocarbon reservoir under control of origin mechanism

    Institute of Scientific and Technical Information of China (English)

    李雄炎; 李洪奇; 周金昱; 龚敏; 张少华

    2012-01-01

    为精准描述低对比度油气层与其他类型储层之间的数学差异,引入特征选择和分类归纳等数学分析模型.所提方法并不要求储层计算参数与储层实际特征完全吻合,只要能准确刻画不同类型流体之间的数值差异即可.以鄂尔多斯盆地陇东地区超低渗透油层改造后的产能预测为例,阐述整个实施过程.结果表明:利用所建产能模型预测77口新井压裂后的产能,平均绝对误差为0 95 t/d,平均相对误差为9.49%,可以满足实际生产需求;在开展或完善储层表征参数理论模型研究的同时,各种数学分析方法的适用性、逻辑性也应被重视;传统方法和数学模型的有效结合能避免方法的单一化或模式化,有助于解决地层评价领域中的各种疑难问题.%In order to accurately identify the mathematical difference between the low contrast hydrocarbon reservoir and other reservoirs and precisely discover the low contrast hydrocarbon reservoir, the feature selection and classification models were introduced. They were applied 1o exploring the particularity of low contrast hydrocarbon reservoir. This method doesn't require the calculated reservoir parameters to be fully equivalent to the practical reservoir characteristics. It will be workable as long as the numerical differences among different types of fluids can be depicted- Taking the productivity forecast of ultra-low permeability oil layer in the Longdong region of Ordos Basin as an example, its whole process was elaborated. The productivity model was utilized to predict the fracturing productivities of 77 new wells. The mean absolute error is 0. 95 t/d and the mean relative error is 9. 49%. And the accuracy rale is satisfactory. The theoretical model of reservoir characterizatiun parameters should be' improved, while the applicability and logicality of the mathematical analysis method should also be given enough attention. Moreover, the effeclive combination

  12. Reservoir characterization and seal integrity of Jemir field in Niger Delta, Nigeria

    Science.gov (United States)

    Adagunodo, Theophilus Aanuoluwa; Sunmonu, Lukman Ayobami; Adabanija, Moruffdeen Adedapo

    2017-05-01

    Ignoring fault seal and depending solely on reservoir parameters and estimated hydrocarbon contacts can lead to extremely unequal division of reserves especially in oil fields dominated by structural traps where faults play an important role in trapping of hydrocarbons. These faults may be sealing or as conduit to fluid flow. In this study; three-dimensional seismic and well log data has been used to characterize the reservoirs and investigate the seal integrity of fault plane trending NW-SE and dip towards south in Jemir field, Niger-Delta for enhanced oil recovery. The petrophysical and volumetric analysis of the six reservoirs that were mapped as well as structural interpretation of the faults were done both qualitatively and quantitatively. In order to know the sealing potential of individual hydrocarbon bearing sand, horizon-fault intersection was done, volume of shale was determined, thickness of individual bed was estimated, and quality control involving throw analysis was done. Shale Gouge Ratio (SGR) and Hydrocarbon Column Height (HCH) (supportable and structure-supported) were also determined to assess the seal integrity of the faults in Jemir field. The petrophysical analysis indicated the porosity of traps on Jemir field ranged from 0.20 to 0.29 and the volumetric analyses showed that the Stock Tank Original Oil in Place varied between 5.5 and 173.4 Mbbl. The SGR ranged from leaking (60%) fault plane suggesting poor to moderate sealing. The supportable HCH of Jemir field ranged from 98.3 to 446.2 m while its Structure-supported HCH ranged from 12.1 to 101.7 m. The porosities of Jemir field are good enough for hydrocarbon production as exemplified by its oil reserve estimates. However, improper sealing of the fault plane might enhance hydrocarbon leakage.

  13. Simulations of hydraulic fracturing and leakage in sedimentary basins

    Energy Technology Data Exchange (ETDEWEB)

    Lothe, Ane Elisabeth

    2004-01-01

    sliding, used as input in the failure criteria, have minor impact on timing and amount of leakage. However, high values result in some time-delay, and thereby less leakage from overpressured compartments. Sensitivity tests of the Poisson's ratio and Young's modulus of the caprock, which controls Biot's constant, show an effect on the overpressure. Defining Biot's constant to 1, gives too early pressure accumulation. Lower values of Biot's constant (larger than0.85) give a present day pressure distribution closer to the one observed in wells. How to obtain a pressure difference across faults is tested on the Tune Field data set. Two different fault maps are used, one with only large faults interpreted, and one with both large and small faults included. High-pressure differences are difficult to obtain when the transmissibility across one individual fault is reduced. The transmissibilities of a network of small faults have to be reduced to match the pressure measured in wells. Then, either our transmissibility fault models are wrong, or a relay zone between larger faults is more sealing than expected. In addition, the fluid flow path can be more complex than expected, and can only be understood with a multi-layer model. The secondary oil migration modelling carried out using different pressure history cases; show that overpressures have a major impact on the migration pathways. The resolution in the fault interpretation is important for the simulation results, both for pressure distribution and for hydrocarbon migration. Minor deformation bands are described from experiments and from onshore fieldwork in Brumunddal. These are small faults situated in a sandstone reservoir that will have influence on lateral fluid flow. (Author)

  14. Simulations of hydraulic fracturing and leakage in sedimentary basins

    Energy Technology Data Exchange (ETDEWEB)

    Lothe, Ane Elisabeth

    2004-01-01

    sliding, used as input in the failure criteria, have minor impact on timing and amount of leakage. However, high values result in some time-delay, and thereby less leakage from overpressured compartments. Sensitivity tests of the Poisson's ratio and Young's modulus of the caprock, which controls Biot's constant, show an effect on the overpressure. Defining Biot's constant to 1, gives too early pressure accumulation. Lower values of Biot's constant (larger than0.85) give a present day pressure distribution closer to the one observed in wells. How to obtain a pressure difference across faults is tested on the Tune Field data set. Two different fault maps are used, one with only large faults interpreted, and one with both large and small faults included. High-pressure differences are difficult to obtain when the transmissibility across one individual fault is reduced. The transmissibilities of a network of small faults have to be reduced to match the pressure measured in wells. Then, either our transmissibility fault models are wrong, or a relay zone between larger faults is more sealing than expected. In addition, the fluid flow path can be more complex than expected, and can only be understood with a multi-layer model. The secondary oil migration modelling carried out using different pressure history cases; show that overpressures have a major impact on the migration pathways. The resolution in the fault interpretation is important for the simulation results, both for pressure distribution and for hydrocarbon migration. Minor deformation bands are described from experiments and from onshore fieldwork in Brumunddal. These are small faults situated in a sandstone reservoir that will have influence on lateral fluid flow. (Author)

  15. The Accumulation Rules of Budate Buried Hill Hydrocarbon Reservoir of Sudeerte Oilfield in Hailar Basin%海拉尔盆地苏德尔特油田布达特潜山油藏成藏规律

    Institute of Scientific and Technical Information of China (English)

    施尚明; 付红军; 樊自立

    2011-01-01

    Metamorphic rock burial hill reservoir of Bell rift in Hailaer Basin, with large scale reservoir and high output, has complex fault system.The fault throughgoing direction roughly is NEE direction, and has wide fault section and lateral quickly changed fault displacement.Through the analysis of the core, debris, electric curve and seismic cross section, metamorphic rock reservoir can be divided in the vertical: weathered fracture zone, crack and corroded hollow and cave development belt, and tight zone.Accumulation is controlled by hydrocarbon ability of source rock, contacting relationship of source rock and reservoir, oil storage ability of reservoir,and vertical and lateral oil-gas migration of fault and unconformity surface.And formed top surface weathering crust accumulation pattern which the oil and gas is lateral migration along the unconformity surface, and inside reservoir pattern of crack broken zone accumulation which oil and gas has the vertical migration along fault.%海拉尔盆地贝尔断陷中的变质岩潜山油藏规模大,产量高.断裂系统复杂,断层展布方向大致为北东东向,断面宽度大、断距横向变化快.变质岩储层在纵向上可分为:风化破碎带,裂缝、溶孔、溶洞发育带和致密带.油藏成藏规律受烃源岩供烃能力及与储层接触关系、储层自身的储油能力、断层及不整合面垂向、侧向运移油气能力控制.形成了以油气沿断裂和不整合面组合侧向运移的布达特群顶面风化壳聚集成藏模式和油气沿断裂垂向运移的布达特群内部裂缝破碎带聚集成藏的内幕油气藏模式.

  16. Hydrocarbon pneumonia

    Science.gov (United States)

    Pneumonia - hydrocarbon ... Coughing Fever Shortness of breath Smell of a hydrocarbon product on the breath Stupor (decreased level of ... Most children who drink or inhale hydrocarbon products and develop ... hydrocarbons may lead to rapid respiratory failure and death.

  17. 海洋可控源电磁法对油气探测能力的仿真分析%Simulation and analysis on the prospecting capability of marine controlled-source electromagnetic methods to hydrocarbon reservoirs

    Institute of Scientific and Technical Information of China (English)

    刘长胜; 周逢道; 林君

    2012-01-01

    The marine controlled-source electromagnetic method (CSEM) is a new technology to detect subsea hydrocarbon reservoirs by electromagnetic fields of low frequency. Its prospecting capability is studied by numerical modeling in this paper. Based on 1D marine model, the electromagnetic responses on seafloor is calculated for different water depth environments and hydrocarbon reservoirs with various buried depth, thickness and resistivities. The biggest relative anomaly and corre- sponding absolute anomaly (i. e. amplitude difference) of electric fields for each buried depth, thickness and resistivity are plotted and the influence of these param- eters on the electromagnetic anomaly is analyzed. The simulation results show that the marine controlled-source electromagnetic method has great performance in sub- sea hydrocarbon reservoirs exploration. small resistivity difference or large buried Even the reservoirs of small thickness, depth in shallow sea environment can leadto considerable electromagnetic anomalies.' When other factors are same, the verti- cal impedance of oil layer decides the biggest electric anomaly. To achieve the opti- mal performance of marine CSEM, appropriate working frequency and receiver off- set are necessary. The study results will provide useful references for the geophysi- cal scheme design of future subsea hydrocarbon exploration.%海洋可控源电磁法是一种采用低频电磁场探测海底油气的新技术,通过仿真分析,研究了该方法对油气的探测能力。基于一维海洋模型,正演计算了不同水深、油气层埋深、油气层厚度和油气层电阻率时海底表面的电磁响应,绘制了最大相对异常幅度和相应的绝对异常幅度随油气埋深、厚度和电阻率变化的曲线,分析了这几种因素对电磁异常幅度的影响。仿真结果表明:海洋可控源电磁法对海底油气具有较强的探测能力,即使在浅海环境,埋深大、厚度薄或

  18. Zero leakage sealings

    Science.gov (United States)

    Kotesovec, Bernhard; Steinrück, Herbert

    2010-11-01

    The piston rod of a reciprocating compressor is sealed with elastic cylindrical sealing elements. Across the sealings the pressure drops from the operating pressure to the ambient pressure. The lubrication gap between the elastic sealing and reciprocating piston rod is studied with the aim to find conditions of a leakage free sealing. The flow in the lubrication gap and the elastic deformation of the sealing are determined simultaneously. The net-flow during one cycle of the reciprocating piston rod is calculated. It turns out that maintaining zero leakage is very sensible. Indeed the outbound flow during out-stroke has to be equal the inbound flow during the in-stroke. By prescribing a special shape of the undeformed sealing zero leakage can be attained - at least theoretically for certain operating conditions. It turns out that temperature dependent material data and a model for cavitation is necessary. The model, its numerical implementation and results will be discussed.

  19. Main controlling factors and exploration potential of hydrocarbon reservoirs in North Gabon sub-Basin%北加蓬次盆油气成藏主控因素分析及勘探潜力评价

    Institute of Scientific and Technical Information of China (English)

    郭念发

    2015-01-01

    北加蓬次盆是一个裂谷盆地与被动大陆边缘盆地叠加形成的中、新生代复合盆地,油气成藏明显受构造运动、沉积环境、盐岩变形等地质因素的控制。盆地东部因抬升剥蚀而遭受不同程度的破坏,烃源岩及油气藏没有很好地保存,导致了东部构造带和西部构造带油气资源贫富差异较大。沉积环境影响储层发育,上白垩统浊积扇砂体和三角洲砂体是盐上层系最重要的储层,油气圈闭的形成与盐岩构造活动密切相关,圈闭类型丰富多彩。根据盐上层系烃源岩和浊积砂体储层分布等地质规律研究,北加蓬次盆大西洋深水斜坡带的中南部处于Azile组主力烃源岩分布区,油气源供给条件优越,储层发育,油气成藏条件得天独厚,是盆地油气勘探最有利的地区。%The North Gabon sub⁃Basin is a Mesozoic-Cenozoic rift and divergent margin basin. The oil and gas reservoirs in the basin were controlled by tectonic movements, sedimentary environments and salt structures. The east of the basin was eroded due to regional uplift, and source rocks and hydrocarbon reservoirs were destroyed, leading to a significant difference of hydrocarbon potential between the east and the west tectonic belts. Sedimen⁃tary environments impacted reservoirs. The Upper Cretaceous turbidity sandstones and offshore sandstones were important reservoirs for the post salt layers. Various traps developed, which were related to salt structure activi⁃ties. Based on research of the turbidity sandstones and offshore sandstones of the post⁃salt layers, the main hydro⁃carbon reservoirs of the North Gabon sub⁃Basin mainly lie on the middle⁃south, deep ocean slope belt, which is the center of the major source rocks of the Azile Formation. Thanks to favorable sourcing and reserving condi⁃tions, the middle⁃south, deep ocean slope belthas considerable hydrocarbon prospects.

  20. Types and characteristics of carbonate reservoirs and their implication on hydrocarbon exploration: A case study from the eastern Tarim Basin, NW China

    Directory of Open Access Journals (Sweden)

    Shiwei Huang

    2017-02-01

    Full Text Available Carbonate rocks are deposited in the Ordovician, Cambrian, and Sinian of eastern Tarim Basin with a cumulative maximum thickness exceeding 2000 m. They are the main carriers of oil and gas, and a great deal of natural gas has been found there in the past five years. Based on lithofacies and reservoir differences, natural gas exploration domains of eastern Tarim Basin can be classified into five types: Ordovician platform limestone; Ordovician platform dolomite; Cambrian platform margin mound shoal; Cambrian slope gravity flow deposits, and; Sinian dolomite. Carbonate reservoir characteristics of all the types were synthetically analyzed through observation on drilling core and thin sections, porosity and permeability measurement, and logging data of over 10 drilling wells. We find distribution of part of good fracture and cave reservoir in carbonate platform limestone of Ordovician. In the Ordovician, platform facies dolomite is better than limestone, and in the Cambrian, platform margin mound shoal dolomite has large stacking thickness. Good quality and significantly thick carbonate gravity deposit flow can be found in the Cambrian slope, and effective reservoir has also been found in Sinian dolomite. Commercial gas has been found in the limestone and dolomite of Ordovician in Shunnan and Gucheng areas. Exploration experiences from these two areas are instructive, enabling a deeper understanding of this scene.

  1. Promising approaches to the purification of soils and groundwater from hydrocarbons (A Review)

    Science.gov (United States)

    Vodyanitskii, Yu. N.; Trofimov, S. Ya.; Shoba, S. A.

    2016-06-01

    Soils and waters are affected by oil spills in the course of oil production and hydrocarbon leakages because of the corrosion of underground reservoirs, as well as the filtration of hydrocarbons from the tailing ponds formed during the extraction of oil from oil sands. The conventional technology for the withdrawal of contaminated water and its purification on the surface is low-efficient and expensive. New approaches are proposed for the in situ purification of soils and groundwater. To accelerate the oxidation, active substances atypical for the supergenesis zone are used: peroxides of metals and hydrogen. The efficiency of hydrogen peroxide significantly increases when the oxidation is catalyzed by Fe2+ or Fe3+ (Fenton reaction). The effects of Fe(III), sulfates, and carbon dioxide as electron acceptors are studied under anaerobic conditions (with oxygen deficit).

  2. 辽河盆地东部凹陷火成岩储层特征及成藏模式%Igneous reservoir characteristics and hydrocarbon accumulation model in eastern sag of Liaohe Basin

    Institute of Scientific and Technical Information of China (English)

    庚琪

    2016-01-01

    按照成岩方式—化学成分—结构+矿物等岩性三级分类原则,识别出5大类23种岩性;根据火成岩的结构、构造和特征岩性,将岩相划分为6相16亚相;按成因将火成岩储集空间分为7种类型9种亚类。通过研究认为岩性、岩相是影响火成岩储层储集性能乃至含油气性的主要因素。火成岩油气成藏的主控因素为烃源岩、储层、构造运动;成藏模式有构造成藏模式、岩性成藏模式、构造—岩性成藏模式3种。通过对火成岩岩性、岩相、储层、成藏的研究,为辽河盆地东部凹陷今后的勘探部署奠定了良好的基础。%Based on the principle of three -level classification of lithology such as diagenetic model ,chemical composi-tion,and structure and mineral ,etc.,the igneous rocks was identified as 5 main classes and 23 types of lithology .Accord-ing to the texture ,structure and characteristic lithology ,the igneous rocks were divided into 6 lithofacies and 16 subfacies . The reservoir spaces were divided into 7 categories and 9 subclasses by the genesis of the igneous rocks .It is considered that the lithology and the lithofacies were main facors controlling reservoir performance and oil -bearing properties .Hydro-carbon accumulation in igneous rocks was mainly controlled by source rock ,reservoir and tectonic movement .Three types of reservoir-forming patterns mainly consist of structural ,lithological ,and structural-lithological patterns .The studies on li-thology ,lithofacies ,reservoir ,and accumulation of igneous rocks have laid a good foundation for future exploration in east -ern Sag of Liaohe Basin .

  3. Assessing Agulhas leakage

    NARCIS (Netherlands)

    van Sebille, E.

    2009-01-01

    Agulhas leakage, the water that flows from the Indian Ocean to the Atlantic Ocean, plays an important role in the circulation of the Atlantic Ocean. The magnitude of this flux of warm and saline Indian Ocean water into the much colder and fresher Atlantic Ocean can be related to the strength of the

  4. Prototyping and Testing a New Volumetric Curvature Tool for Modeling Reservoir Compartments and Leakage Pathways in the Arbuckle Saline Aquifer: Reducing Uncertainty in CO2 Storage and Permanence

    Energy Technology Data Exchange (ETDEWEB)

    Rush, Jason [Univ. of Kansas and Kansas Geological Survey, Lawrence, KS (United States); Holubnyak, Yevhen [Univ. of Kansas and Kansas Geological Survey, Lawrence, KS (United States); Watney, Willard [Univ. of Kansas and Kansas Geological Survey, Lawrence, KS (United States)

    2016-12-09

    This DOE-funded project evaluates the utility of seismic volumetric curvature (VC) for predicting stratal and structural architecture diagnostic of paleokarst reservoirs. Of special interest are applications geared toward carbon capture, utilization, and storage (CCUS). VC has been championed for identifying faults (offset <¼ λ) that cannot be imaged by conventional 3-D seismic attributes such as coherence. The objective of this research was to evaluate VC-techniques for reducing uncertainties in reservoir compartmentalization studies and seal risk assessments especially for saline aquifers. A 2000-ft horizontal lateral was purposefully drilled across VC-imaged lineaments—interpreted to record a fractured and a fault-bounded doline—to physically confirm their presence. The 15-mi² study area is located in southeastern Bemis-Shutts Field, which is situated along the crest of the Central Kansas Uplift (CKU) in Ellis County, Kansas. The uppermost Arbuckle (200+ ft) has extensive paleokarst including collapsed paleocaverns and dolines related to exceedingly prolonged pre-Simpson (Sauk–Tippecanoe) and/or pre-Pennsylvanian subaerial exposure. A lateral borehole was successfully drilled across the full extent (~1100 ft) of a VC-inferred paleokarst doline. Triple combo (GR-neutron/density-resistivity), full-wave sonic, and borehole micro-imager logs were successfully run to TD on drill-pipe. Results from the formation evaluation reveal breccias (e.g., crackle, mosaic, chaotic), fractures, faults, vugs (1-6"), and unaffected host strata consistent with the pre-spud interpretation. Well-rounded pebbles were also observed on the image log. VC-inferred lineaments coincide with 20–80-ft wide intervals of high GR values (100+ API), matrix-rich breccias, and faults. To further demonstrate their utility, VC attributes are integrated into a geocellular modeling workflow: 1) to constrain the structural model; 2) to generate facies probability grids, and; 3) to collocate

  5. Pyroclastic deposits:an important reservoir for hydrocarbon accumulation%火山碎屑沉积物是油气的重要储层

    Institute of Scientific and Technical Information of China (English)

    刘祥; 郎建军; 杨清福

    2011-01-01

    Pyroclastic deposits are important reservoirs and can be divided into fallout tephradeposits, pyroclastic flow deposits, lahar deposits and base surge deposits by their genesis. The four kinds of pyroclastic deposits have different reservoir characteristics and potential. The identification and interpretation of the pyroclastic deposits can significantly influence the exploration methods of volcaniclastic sequences and the prediction of reservoir geometry and quality. The Lower Jurassic Wrightson Formation in Arizona is a multi-crater complex. Its pyroclastic deposits and lavas with various genesis can be divided into crater, proximal, middle and distal facies. The influences of these facies on reservoir quality are discussed. Volcanic clasts are mostly composed of chemically active and unstable minerals that can change rapidly and extensively during burial diagenesis. The occurrence of volcanic clasts may contribute to the development of dissolution porosity which can enhance reservoir quality.%火山碎屑沉积物是重要的油气储层.火山碎屑沉积按成因划分为火山喷发空中降落堆积物、火山碎屑流状堆积物、火山泥流堆积物和火山基浪堆积物等.它们的特征和储层潜能是不同的.火山碎屑沉积物的识别和解释能够极大的影响火山碎屑层序的勘探方法、储油层几何形态和性能的预测.美国亚利桑那洲早侏罗世怀特申组是一个多喷发火山口复合体,把不同成因类型的火山碎屑堆积物和熔岩分为4个相:火口相、近火口相、中间相和远端相.讨论了这些相对储层性能的影响.火山碎屑大部分由化学性活泼的和不稳定矿物组成,在埋藏成岩期间具有迅速和广泛的变化.火山碎屑的赋存,有助于溶解孔隙的发育,能够增强储油层性能.

  6. A reconstruction method of porosity for clastic reservoirs during the crucial period of hydrocarbon accumulation%关键成藏期碎屑岩储层古孔隙度恢复方法

    Institute of Scientific and Technical Information of China (English)

    渠冬芳; 姜振学; 刘惠民; 高永进

    2012-01-01

    油气的成藏过程是地质历史时期的事件,恢复储层在地质历史时期,尤其是在关键成藏期的孔隙度可以帮助定量恢复成藏期的地质条件,更好地认识油气成藏的过程.笔者以将今论古的地质思想为指导,创建了关键成藏期储层孔隙度的恢复方法.以东营凹陷沙河街组四段上亚段(简称沙四上亚段)储层为例,在对其成岩作用类型和成岩阶段划分的基础上,分别对处于不同成岩阶段的一定深度下的储层孔隙度影响因素进行分析,提出了孔隙度综合影响因子的新概念;建立了在孔隙度综合影响因子约束下的孔隙度演化曲线;最后利用此孔隙度演化曲线,对东曾凹陷草11-王59剖面上的沙四上亚段储层在几个关键成藏期的古孔隙度进行了恢复.结果表明,用该方法进行的古孔隙度恢复取得了较好的效果.%A hydrocarbon accumulation process is an event of geological history. In order to better understand this event, the reconstruction of reservoir porosity during geological history, especially in a crucial period of hydrocarbon accumulation, can help in quantitatively reconstructing geological conditions of hydrocarbon accumulation. Based on a geological thought of "uniformitarianism", the present paper established a new method to reconstruct reservoir porosity of the crucial hydrocarbon accumulation. Taking the 4th member of the Shahejie Formation as an example and based on its classification of diagenetic types and stages, we proposed a new concept of combined porosity influencing factor(F for short) by investigating factors that influence the porosity of sandstones with a certain depth at different diagenetic stages, established an evolutionary curve of porosity that is restricted by combined porosity influencing factors, and finally reconstructed the paleo-porosity in crucial hydrocarbon accumulation periods for the 4th member of the Shahejie Formation in the Cao 11-Wang 59 section

  7. 鄂尔多斯盆地延长组下组合油气来源及成藏模式%Hydrocarbon origin and reservoir forming model of the Lower Yanchang Formation, Ordos Basin

    Institute of Scientific and Technical Information of China (English)

    李相博; 刘显阳; 周世新; 刘化清; 陈启林; 王菁; 廖建波; 黄军平

    2012-01-01

    通过生物标志化合物对比、流体包裹体分析及盆地模拟研究,对鄂尔多斯盆地延长组长9与长10油层组的油源、成藏期次及成藏模式进行了探讨.陇东与姬塬地区长9油层组的原油分为2种类型,第Ⅰ类来源于长7烃源岩,第Ⅱ类来源于长9烃源岩;陕北地区长10油层组的原油主要来源于长9烃源岩.陇东与姬塬地区长9油藏均发生过2期油气充注,但前者在第1期(中侏罗统直罗组沉积期)就达到了油气充注的高峰期,而后者在第2期(下白垩统志丹组沉积期)才达到油气充注高峰期;陕北长10油层组也存在2期成藏,但2期油气呈连续充注,大致从中侏罗统直罗组沉积早期一直持续到下白垩统志丹组沉积中后期.长9与长10油藏有“上生下储”、“侧生旁储”及“自生自储”3种成藏模式.图10参22%According to the comparison of biomarkers in source rocks and crude oil, fluid inclusion analysis, and basin modeling, this paper discusses the oil source, hydrocarbon accumulation period and reservoir forming model of the Chang 9 and Chang 10 oil-bearing formations, Yanchang Formation, Ordos Basin. The crude oil of Chang 9 in the Longdong and Jiyuan areas can be divided into two types, type I crude oil originated from the source rocks within Chang 7, while type II crude oil came from the source rocks within Chang 9. The crude oil of Chang 10 in Northern Shaanxi originated mainly from the source rocks of Chang 9. The Chang 9 oil reservoirs in both the Longdong and Jiyuan areas experienced two periods of hydrocarbon injection. The former reached the peak period of hydrocarbon injection in the first period (the depositional period of Middle Jurassic Zhiluo Formation), while the latter in the second period (the depositional period of Lower Cretaceous Zhidan Formation). There are two periods of continuous hydrocarbon injection in Chang 10 of Northern Shaanxi, generally from the early depositional period of

  8. Colorectal Anastomotic Leakage: New perspectives

    NARCIS (Netherlands)

    F. Daams (Freek)

    2014-01-01

    markdownabstract__Abstract__ This thesis provides new perspectives on colorectal anastomotic leakages. In both experimental and clinical studies, aspects of prevention, early identification, treatment and consequences of anastomotic leakage are discussed.

  9. 基于元建模的裂缝性气藏累计产量预测%Prediction of accumulated outflow from a fractured hydrocarbon reservoir using metamodeling

    Institute of Scientific and Technical Information of China (English)

    Seifi A; Kazemzadeh M B; Mohammadi H

    2013-01-01

    Three metamodels were established for predicting accumulated outflow from a fractured hydrocarbon reservoir over a planning horizon of 18 years, and the models were validated and compared using accumulated outflow predicted by numerical simulation. The reservoir was simulated and its basic parameters (porosity, permeability and water saturation) were estimated. The accumulated outflow over 18 years of a well in the reservoir was expressed as a function of the reservoir parameters. Low potential points were excluded using HIP (Hydrocarbon in Place) equation and 25 high potential points were chosen as design points using maximum entropy design. Three kinds of metamodels (quadratic model, multiplicative model and radial basis function model) were built and the accumulated outflows of 25 design points and 7 test points were predicted based on the models. The prediction results show that all of the three models can accurately predict the accumulated outflow of the reservoir studied in this paper and the radial basis function model outperforms the other two metamodels. Besides, the calculating time of the metamodeling method is much less than that of the numerical simulation.%  为了预测某裂缝性气藏在18年规划周期内的累计产量,建立了3种元模型,并结合数值模拟累计产量预测结果对各模型进行了验证和对比。估算了气藏的基本参数(孔隙度、渗透率及含水饱和度)并对气藏进行了数值模拟。将气藏内某井18年内的累计产量表示为各气藏参数的函数,采用储量计算经验函数排除了研究空间内的低潜力点,并基于最大熵准则选取25个高潜力点作为设计点。建立了二次模型、乘性模型和 RBF 模型3种元模型,基于各模型预测了25个设计点和7个试验点处的累计产量。预测结果表明:各模型均能比较准确地预测累计产量;RBF模型的累计产量预测准确性优于另外2种模型;与数值模拟方法相

  10. 深部热流体对油气成藏的影响%Influences of Deeply Sourced Thermal Fluid on the Formation of Hydrocarbon Reservoirs

    Institute of Scientific and Technical Information of China (English)

    高波; 陶明信; 王万春

    2001-01-01

    Deeply sourced thermal fluid is a kind of supercritical fluidcomposed of several constituents. Rising upward, it can transmit energy and material, and regulate and redistribute them in the inner Earth. For the formation of oil and gas, hypogene hydrothermal fluid can increase the paleotemperature of depositional basin, accelerate the evolution history of source rocks and enlarge the volume of effective source rocks. It can also extract and enrich dispersive organic matter in sediments because of its higher dissolving and diffusing capacity, and obviously contribute hydrogen to hydrocarbon generation. So the deeply sourced thermal fluid provides part of material resources for hydrocarbon generation. In addition, the reaction between thermal fluid and surrounding rocks can improve their porosity and permeability. This is favorable for the migration and accumulation of hydrocarbons. Moreover, that the higher pressure and water content of thermal fluid can significantly retard the thermal destruction of hydrocarbon is advantageous to the preservation of oil and gas.%深部热流体是一种由多元组分构成的超临界流体,其上升活动可使地球内部的物质与能量发生调整或再分配。对油气而言,深部热流体携带的高热能可使沉积盆地的古地温升高,加快烃源岩的热演化进程,增加有效烃源岩的体积,促进烃类的生成;在上升过程中,因其具很强的溶解和扩散能力,故可萃取、富集沉积物中的分散有机质,同时又对生烃产生显著的加氢作用,从而为油气的形成补充物源。此外,热流体与围岩储层发生化学反应,可改善储层的孔渗条件,有利于油气的聚集成藏,而且因其具有较高的压力和含水量,可抑制烃类的热裂解而有利于油气的保存。

  11. DETERMINATION OF LOW PERMEABLE LITHOFACIES, AS TYPE OF UNCONVENTIONAL HYDROCARBON RESERVOIRS, USING SEQUENTIAL INDICATOR METHODS, CASE STUDY FROM THE KLOŠTAR FIELD

    Directory of Open Access Journals (Sweden)

    Kristina Novak Zelenika

    2014-07-01

    Full Text Available Geostatistical methods are very successfully used in Upper Miocene (Lower Pontian Kloštar structure modelling. Mapping of the two variables (porosity and thickness and their common observation in certain cut-off values gave the insight in depositional channel location, transitional lithofacies, material transport direction and variables distribution within representative Lower Pontian reservoir. It was possible to observe direction of the turbidites and role of the normal fault in detritus flow direction in the analyzed structure. Intercalation between turbiditic sandstones and basinal pelitic marls were the locations with the highest thicknesses. Sequential Indicator Simulations highlighted porosity maps as primary and thickness maps as secondary (additional data source (the paper is published in Croatian.

  12. Leakage resilient password systems

    CERN Document Server

    Li, Yingjiu; Deng, Robert H

    2015-01-01

    This book investigates tradeoff between security and usability in designing leakage resilient password systems (LRP) and introduces two practical LRP systems named Cover Pad and ShadowKey. It demonstrates that existing LRP systems are subject to both brute force attacks and statistical attacks and that these attacks cannot be effectively mitigated without sacrificing the usability of LRP systems. Quantitative analysis proves that a secure LRP system in practical settings imposes a considerable amount of cognitive workload unless certain secure channels are involved. The book introduces a secur

  13. Dating reservoir filling - a case history from the North Sea

    Energy Technology Data Exchange (ETDEWEB)

    Bhullar, Abid G.; Karlsen, Dag A.; Backer-Owe, Kristian [Oslo Dept. of Geology, Petroleum Geochemistry Program, Blindern, Oslo (Norway); Seland, Reinert T. [Aker Geo Petroleum Services asa, Hillevaag (Norway); Le Tran, Khanh [Elf Aquitaine Production, CSTJF, Pau, 64 (France)

    1999-11-01

    temperature, filling of the Froy Field and main Rind structure is suggested to have been a recent event. A presently dry compartment penetrated by well 25/2-15R2 in the Rind Discovery contains high residual oil saturations, indicating loss of oil from this structure either by direct cap rock leakage or displacement of oil by gas and subsequent cap rock leakage. Numerous petroleum and coexisting water inclusions were found in the presently dry overpressure structure and it is clear from measurements of homogenisation temperatures that the water and the petroleum inclusions are not both saturated with respect to gas. Due to the lower solubility of hydrocarbon gas in water compared to in oil, it is more likely that water inclusions are closer to saturation than are the petroleum inclusions. Using the difference in homogenisation temperatures in these two systems and the burial history, we tentatively suggest that the cap rock leakage occurred later than 10 m.y.b.p. Such information on time for reservoir filling and seal failure, when used to calibrate basin modelling, should facilitate better models for understanding movement of hydrocarbon fluids in basins. (Author)

  14. The glaciogenic reservoir analogue studies project (GRASP)

    DEFF Research Database (Denmark)

    Moscariello, A.; Moreau, Julien; Vegt, P. van der

    Tunnel galleys are common features in Palaeozoic glacigenic succession in North Afrcica and Middle East and they are amongst the most challenging target for hydrocarbon exploration and developing drilling in these regions. Similarly, these buried valleys form important groundwater reservoirs...

  15. Monetizing Leakage Risk of Geologic CO2 Storage using Wellbore Permeability Frequency Distributions

    Science.gov (United States)

    Bielicki, Jeffrey; Fitts, Jeffrey; Peters, Catherine; Wilson, Elizabeth

    2013-04-01

    Carbon dioxide (CO2) may be captured from large point sources (e.g., coal-fired power plants, oil refineries, cement manufacturers) and injected into deep sedimentary basins for storage, or sequestration, from the atmosphere. This technology—CO2 Capture and Storage (CCS)—may be a significant component of the portfolio of technologies deployed to mitigate climate change. But injected CO2, or the brine it displaces, may leak from the storage reservoir through a variety of natural and manmade pathways, including existing wells and wellbores. Such leakage will incur costs to a variety of stakeholders, which may affect the desirability of potential CO2 injection locations as well as the feasibility of the CCS approach writ large. Consequently, analyzing and monetizing leakage risk is necessary to develop CCS as a viable technological option to mitigate climate change. Risk is the product of the probability of an outcome and the impact of that outcome. Assessment of leakage risk from geologic CO2 storage reservoirs requires an analysis of the probabilities and magnitudes of leakage, identification of the outcomes that may result from leakage, and an assessment of the expected economic costs of those outcomes. One critical uncertainty regarding the rate and magnitude of leakage is determined by the leakiness of the well leakage pathway. This leakiness is characterized by a leakage permeability for the pathway, and recent work has sought to determine frequency distributions for the leakage permeabilities of wells and wellbores. We conduct a probabilistic analysis of leakage and monetized leakage risk for CO2 injection locations in the Michigan Sedimentary Basin (USA) using empirically derived frequency distributions for wellbore leakage permeabilities. To conduct this probabilistic risk analysis, we apply the RISCS (Risk Interference of Subsurface CO2 Storage) model (Bielicki et al, 2013a, 2012b) to injection into the Mt. Simon Sandstone. RISCS monetizes leakage risk

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

    Institute of Scientific and Technical Information of China (English)

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

    2011-01-01

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

  17. Experimental determination of methane dissolution from simulated subsurface oil leakages

    Science.gov (United States)

    Sauthoff, W.; Peltzer, E. T.; Walz, P. M.; Brewer, P. G.

    2013-12-01

    Subsurface oil leakages and increased offshore drilling efforts have raised concern over the fate of hydrocarbon mixtures of oil and gas in ocean environments. Recent wellhead and pipeline failures in the Gulf of Mexico are extreme examples of this problem. Understanding the mechanism and rate of vertical transport of hydrocarbon chemical species is necessary to predict the environmental impact of subsurface leakages. In a series of controlled experiments, we carried out a deep-sea field experiment in Monterey Canyon to investigate the behavior of a gas-saturated liquid hydrocarbon mass rising from the seafloor. Aboard the R/V Rachel Carson, we used the ROV Ventana to transport a laboratory prepared volume of decane (C10H22) saturated with methane gas (CH4) to mimic a subsurface seafloor discharge. We released the oil and gas mixture into a vertically oriented open bottom glass tube followed by methane loss rate measurements both at discrete depths, and during rapid, continuous vehicle ascent from 800 to 100 m water depth to monitor changes in dissolution and bubble nucleation. Using laser Raman techniques and HD video we quantified the chemical state of the hydrocarbon fluid, including rate of methane gas dissolution. The primary methane Raman peak was readily observable within the decane C-H stretching complex. Variation in the amount of gas dissolved in the oil greatly influences oil plume density and in turn oil plume vertical rise rate. Our results show that the rise rate of the hydrocarbon mass significantly exceeds the rate at which the excess methane was lost by dissolution. This result implies that vertical transport of methane in the saturated hydrocarbon liquid phase can greatly exceed a gas bubble plume ascending the water column from a seafloor source. These results and observations may be applicable to improved understanding of the composition, distribution, and environmental fate of leaked hydrocarbon mixtures and inform remediation efforts.

  18. Advances in carbonate exploration and reservoir analysis

    Science.gov (United States)

    Garland, J.; Neilson, J.E.; Laubach, S.E.; Whidden, K.J.

    2012-01-01

    Carbonate reservoirs contain an increasingly important percentage of the world’s hydrocarbon reserves. This volume presents key recent advances in carbonate exploration and reservoir analysis. As well as a comprehensive overview of the trends in carbonate over the years, the volume focuses on four key areas:

  19. Leakage-free journal bearings

    Science.gov (United States)

    Pinkus, O.; Etsion, I.

    1976-01-01

    A new concept of a journal bearing is developed which prevents side leakage of the lubricant, thus eliminating the need for sealing and collecting this leakage. The cooling of the bearing is accomplished by the prevailing circumferential flow. An analysis is performed and solutions are given for the bearing geometries and inlet pressures required to achieve the above purpose.

  20. Duct Leakage Repeatability Testing

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sherman, Max [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2014-01-01

    Duct leakage often needs to be measured to demonstrate compliance with requirements or to determine energy or Indoor Air Quality (IAQ) impacts. Testing is often done using standards such as ASTM E1554 (ASTM 2013) or California Title 24 (California Energy Commission 2013 & 2013b), but there are several choices of methods available within the accepted standards. Determining which method to use or not use requires an evaluation of those methods in the context of the particular needs. Three factors that are important considerations are the cost of the measurement, the accuracy of the measurement and the repeatability of the measurement. The purpose of this report is to evaluate the repeatability of the three most significant measurement techniques using data from the literature and recently obtained field data. We will also briefly discuss the first two factors. The main question to be answered by this study is to determine if differences in the repeatability of these tests methods is sufficient to indicate that any of these methods is so poor that it should be excluded from consideration as an allowed procedure in codes and standards.

  1. Multifamily Envelope Leakage Model

    Energy Technology Data Exchange (ETDEWEB)

    Faakye, Omari [Consortium for Advanced Residential Buildings, Norwalk, CT (United States); Griffiths, Dianne [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)

    2015-05-08

    “The cost for blower testing is high, because it is labor intensive, and it may disrupt occupants in multiple units. This high cost and disruption deter program participants, and dissuade them from pursuing energy improvements that would trigger air leakage testing, such as improvements to the building envelope.” This statement found in a 2012 report by Heschong Mahone Group for several California interests emphasizes the importance of reducing the cost and complexity of blower testing in multifamily buildings. Energy efficiency opportunities are being bypassed. The cost of single blower testing is on the order of $300. The cost for guarded blower door testing—the more appropriate test for assessing energy savings opportunities—could easily be six times that, and that’s only if you have the equipment and simultaneous access to multiple apartments. Thus, the proper test is simply not performed. This research seeks to provide an algorithm for predicting the guarded blower door test result based upon a single, total blower door test.

  2. A finite element simulation system in reservoir engineering

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Xiaozhong [Louisiana State Univ., Baton Rouge, LA (United States)

    1996-03-01

    Reservoir engineering is performed to predict the future performance of a reservoir based on its current state and past performance and to explore other methods for increasing the recovery of hydrocarbons from a reservoir. Reservoir simulations are routinely used for these purposes. A reservoir simulator is a sophisticated computer program which solves a system of partial differential equations describing multiphase fluid flow (oil, water, and gas) in a porous reservoir rock. This document describes the use of a reservoir simulator version of BOAST which was developed by the National Institute for Petroleum and Energy Research in July, 1991.

  3. Gas sealing efficiency of cap rocks. Pt. 1: Experimental investigations in pelitic sediment rocks. - Pt. 2: Geochemical investigations on redistribution of volatile hydrocarbons in the overburden of natural gas reservoirs; Gas sealing efficiency of cap rocks. T. 1: Experimentelle Untersuchungen in pelitischen Sedimentgesteinen. - T.2: Geochemische Untersuchungen zur Umverteilung leichtfluechtiger Kohlenwasserstoffe in den Deckschichten von Erdgaslagerstaetten. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Leythaeuser; Konstanty, J.; Pankalla, F.; Schwark, L.; Krooss, B.M.; Ehrlich, R.; Schloemer, S.

    1997-09-01

    New methods and concepts for the assessment of sealing properties of cap rocks above natural gas reservoirs and of the migration behaviour of low molecular-weight hydrocarbons in sedimentary basins were developed and tested. The experimental work comprised the systematic assesment of gas transport parameters on representative samples of pelitic rocks at elevated pressure and temperature conditions, and the characterization of their sealing efficiency as cap rocks overlying hydrocarbon accumulations. Geochemical case histories were carried out to analyse the distribution of low molecular-weight hydrocarbons in the overburden of known natural gas reservoirs in NW Germany. The results were interpreted with respect to the sealing efficiency of individual cap rock lithologies and the type and extent of gas losses. (orig.) [Deutsch] Zur Beurteilung der Abdichtungseigenschaften von Caprocks ueber Gaslagerstaetten und des Migrationsverhaltens niedrigmolekularer Kohlenwasserstoffe in Sedimentbecken wurden neue Methoden und Konzepte entwickelt und angewendet. In experimentellen Arbeiten erfolgte die systematische Bestimmung von Gas-Transportparametern an repraesentativen Proben pelitischer Gesteine unter erhoehten Druck- und Temperaturbedingungen und die Charakterisierung ihrer Abdichtungseffizienz als Deckschicht ueber Kohlenwasserstofflagerstaetten. In geochemischen Fallstudien wurde die Verteilung niedrigmolekularer Kohlenwasserstoffe in den Deckschichten ueber bekannten Erdgaslagerstaetten in NW-Deutschland analysiert und im Hinblick auf die Abdichtungseffizienz einzelner Caprock-Lithologien bzw. Art und Ausmass von Gasverlusten interpretiert. (orig.)

  4. TWO NEW DUCT LEAKAGE TESTS

    Energy Technology Data Exchange (ETDEWEB)

    ANDREWS,J.W.

    1998-12-01

    Two variations on the tests for duct leakage currently embodied in ASHRAE Standard 152P (Method of Test for Determining the Design and Seasonal Efficiencies of Residential Thermal Distribution Systems) are presented. Procedures are derived for calculating supply and return duct leakage to/from outside using these new variations. Results of these tests are compared with the original ones in Standard 152P on the basis of data collected in three New York State homes.

  5. Coalbed methane reservoir boundaries and sealing mechanism

    Institute of Scientific and Technical Information of China (English)

    SU Xianbo; LIN Xiaoying; LIU Shaobo; SONG Yan

    2005-01-01

    It is important to investigate the coalbed methane reservoir boundaries for the classification, exploration, and development of the coalbed methane reservoir.Based on the investigation of the typical coalbed methane reservoirs in the world, the boundaries can be divided into four types: hydrodynamic boundary, air altered boundary,permeability boundary, and fault boundary. Hydrodynamic and air altered boundaries are ubiquitous boundaries for every coalbed methane reservoir. The four types of the fault sealing mechanism in the petroleum geological investigation (diagen- esis, clay smear, juxtaposition and cataclasis) are applied to the fault boundary of the coalbed methane reservoir. The sealing mechanism of the open fault boundary is the same with that of the hydrodynamic sealing boundary.The sealing mechanism of the permeability boundary is firstly classified into capillary pressure sealing and hydrocarbon concentration sealing. There are different controlling boundaries in coalbed methane reservoirs that are in different geological backgrounds. Therefore, the coalbed methane reservoir is diversiform.

  6. Optrode for sensing hydrocarbons

    Science.gov (United States)

    Miller, Holly; Milanovich, Fred P.; Hirschfeld, Tomas B.; Miller, Fred S.

    1987-01-01

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons.

  7. Multiple-Element Matching Reservoir Formation and Quantitative Prediction of Favorable Areas in Superimposed Basins

    Institute of Scientific and Technical Information of China (English)

    WANG Huaijie; PANG Xiongqi; WANG Zhaoming; YU Qiuhua; HUO Zhipeng; MENG Qingyang

    2010-01-01

    Superimposed basins in West China have experienced multi-stage tectonic events and multicycle hydrocarbon reservoir formation,and complex hydrocarbon reservoirs have been discovered widely in basins of this kind.Most of the complex hydrocarbon reservoirs are characterized by relocation,scale re-construction,component variation and phase state transformation,and their distributions are very difficult to predict.Research shows that regional caprock(C),high-quality sedimentary facies(Deposits,D),paleohighs(Mountain,M)and source rock(S)are four geologic elements contributing to complex hydrocarbon reservoir formation and distribution of western superimposed basins.Longitudinal sequential combinations of the four elements control the strata of hydrocarbon reservoir formation,and planar superimpositions and combinations control the range of hydrocarbon reservoir and their simultaneous joint effects in geohistory determine the time of hydrocarbon reservoir formation.Multiple-element matching reservoir formation presents a basic mode of reservoir formation in superimposed basins,and we recommend it is expressed as T-CDMS.Based on the multiple-element matching reservoir formation mode,a comprehensive reservoir formation index(Tcdms)is developed in this paper to characterize reservoir formation conditions,and a method is presented to predict reservoir formation range and probability of occurrence in superimposed basins.Through application of new theory,methods and technology,the favorable reservoir formation range and probability of occurrence in the Ordovician target zone in Tarim Basin in four different reservoir formation periods are predicted.Results show that central Tarim,Yinmaili and Lunnan are the three most favorable regions where Ordovician oil and gas fields may have formed.The coincidence of prediction results with currently discovered hydrocarbon reservoirs reaches 97%.This reflects the effectiveness and reliability of the new theory,methods and technology.

  8. Inverting subsidence data to detect possible compartmentalization in a gas reservoir in The Netherlands

    NARCIS (Netherlands)

    Visser, K.; Muntendam-Bos, A.G.; Kunakbayeva, G.; Leeuwenburgh, O.; Peters, E.; Fokker, P.A.

    2010-01-01

    Subsidence can be induced by hydrocarbon production, due to the decrease in pore pressure in the reservoir which causes the reservoir to compact. The subsidence at any point on the surface is a result of the compaction over a large area of the reservoir. The properties of the reservoir and thus the

  9. The integration of geology, geophysics, petrophysics and petroleum engineering in reservoir delineation, description and management

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    This book covers the proceedings of the first Archie Conference. Topics covered include: reservoir characterization: petrophysical formation evaluation; reservoir properties prediction; origin, description and evaluation of fractured reservoirs; 2-D and 3-D in seismic reservoir delineation and development, and the utilization of geoscience and engineering technology to increase hydrocarbon recovery.

  10. Abnormal pressure in hydrocarbon environments

    Science.gov (United States)

    Law, B.E.; Spencer, C.W.

    1998-01-01

    Abnormal pressures, pressures above or below hydrostatic pressures, occur on all continents in a wide range of geological conditions. According to a survey of published literature on abnormal pressures, compaction disequilibrium and hydrocarbon generation are the two most commonly cited causes of abnormally high pressure in petroleum provinces. In young (Tertiary) deltaic sequences, compaction disequilibrium is the dominant cause of abnormal pressure. In older (pre-Tertiary) lithified rocks, hydrocarbon generation, aquathermal expansion, and tectonics are most often cited as the causes of abnormal pressure. The association of abnormal pressures with hydrocarbon accumulations is statistically significant. Within abnormally pressured reservoirs, empirical evidence indicates that the bulk of economically recoverable oil and gas occurs in reservoirs with pressure gradients less than 0.75 psi/ft (17.4 kPa/m) and there is very little production potential from reservoirs that exceed 0.85 psi/ft (19.6 kPa/m). Abnormally pressured rocks are also commonly associated with unconventional gas accumulations where the pressuring phase is gas of either a thermal or microbial origin. In underpressured, thermally mature rocks, the affected reservoirs have most often experienced a significant cooling history and probably evolved from an originally overpressured system.

  11. The role of petroleum engineering on geothermal reservoir assessments

    Energy Technology Data Exchange (ETDEWEB)

    Alkan, H. [ISTec, Koeln (Germany)

    2008-02-15

    Reservoir assessment is the most critical issue of the risk analysis on the use of a geothermal energy source and requires a multi disciplinary survey of the underground objective. Petroleum reservoir engineering with its methodology and its actual technology level fits well with the needs of geothermal reservoir assessments. In this study similarities and differences of the hydrocarbon and geothermal reservoirs are discussed briefly in terms of exploration and production. Furthermore the petroleum reservoir engineering techniques which are currently used and which can be used in geothermal reservoir assessments are summarized. (orig.)

  12. Air-Leakage Control Manual.

    Energy Technology Data Exchange (ETDEWEB)

    Maloney, Jim; Washington State Energy Office; United States. Bonneville Power Administration.

    1991-05-01

    This manual is for builders and designers who are interested in building energy-efficient homes. The purpose of the manual is to provide the how and why'' of controlling air leakage by means of a system called the Simple Caulk and Seal'' (SIMPLE{center dot}CS) system. This manual provides an overview of the purpose and contents of the manual; It discusses the forces that affect air leakage in homes and the benefits of controlling air leakage. Also discussed are two earlier approaches for controlling air leakage and the problems with these approaches. It describes the SIMPLE-{center dot}CS system. It outlines the standard components of the building envelope that require sealing and provides guidelines for sealing them. It outlines a step-by-step procedure for analyzing and planning the sealing effort. The procedure includes (1) identifying areas to be sealed, (2) determining the most effective and convenient stage of construction in which to do the sealing, and (3) designating the appropriate crew member or trade to be responsible for the sealing.

  13. Air-leakage control manual

    Energy Technology Data Exchange (ETDEWEB)

    Maloney, J. [Washington State Energy Office, Olympia, WA (United States)

    1991-05-01

    This manual is for builders and designers who are interested in building energy-efficient homes. The purpose of the manual is to provide the ``how and why`` of controlling air leakage by means of a system called the ``Simple Caulk and Seal`` (SIMPLE{center_dot}CS) system. This manual provides an overview of the purpose and contents of the manual; It discusses the forces that affect air leakage in homes and the benefits of controlling air leakage. Also discussed are two earlier approaches for controlling air leakage and the problems with these approaches. It describes the SIMPLE-{center_dot}CS system. It outlines the standard components of the building envelope that require sealing and provides guidelines for sealing them. It outlines a step-by-step procedure for analyzing and planning the sealing effort. The procedure includes (1) identifying areas to be sealed, (2) determining the most effective and convenient stage of construction in which to do the sealing, and (3) designating the appropriate crew member or trade to be responsible for the sealing.

  14. “Complementarity” Feature of Hydrocarbon Distribution in Oil-rich Sag

    Institute of Scientific and Technical Information of China (English)

    DuJinhu; YiShiwei; LuXuejun; WangQuan

    2004-01-01

    Based on the research and exploration of lithostratigraphic reservoir in me Jizhong depression of the Bohai Bay basin and Erlian basin, the hydrocarbon distribution in a continental oil-rich sag has "complementarity" feature, viz. the hydrocarbon resources configuration and plane distribution of the structural reservoir and lithostratigraphic reservoir have the "complementarity". This distribution feature is controlled by many factors such as the macroscopical geological setting, reservoir-forming condition, and the reservoir-forming mechanism of structural reservoir and lithostratigraphic reservoir. More research shows that the "complementarity" of hydrocarbon distribution is prevalent in every kind of continental basin. This "rule" helps to establish a new exploration theory, a scientific exploration program, and make proper exploration deployments in hydrocarbon exploration. Therefore, it is significant for the exploration work in continental petroliferous basins of China.

  15. A contribution to risk analysis for leakage through abandoned wells in geological CO2 storage

    DEFF Research Database (Denmark)

    Kopp, Andreas; Binning, Philip John; Johannsen, K.;

    2010-01-01

    reservoir database, holding data from over 1200 reservoirs An analytical risk equation is given, allowing the calculation of average risk due to multiple leaky wells with varying distance in the surrounding of the injection well. The reservoir parameters most affecting risk are identified. Using...... these results, the placement of an injection well can be optimized with respect to risk and uncertainty of leakage The risk and uncertainty assessment can be used to determine whether a site, compared to others, should be considered for further investigations or rejected for CO2 storage...

  16. The presence of hydrocarbons in southeast Norway

    DEFF Research Database (Denmark)

    Hanken, Niels Martin; Hansen, Malene Dolberg; Kresten Nielsen, Jesper

    Hydrocarbons, mostly found as solid pyrobitumen, are known from more than 30 localities in southeast Norway. They occur as inclusions in a wide range of "reservoir rocks" spanning from Permo-Carboniferous breccias to veins (vein quartz and calcite veins) in Precambrian granites, gneisses and amph......Hydrocarbons, mostly found as solid pyrobitumen, are known from more than 30 localities in southeast Norway. They occur as inclusions in a wide range of "reservoir rocks" spanning from Permo-Carboniferous breccias to veins (vein quartz and calcite veins) in Precambrian granites, gneisses...

  17. Oil sand reservoir heterogeneity and prediction of hydrocarbon migration channels——a case study on west slope of Songliao Basin%油砂储层非均质性的研究及对油气运移通道的预测——以松辽盆地西部斜坡为例

    Institute of Scientific and Technical Information of China (English)

    罗洪浩; 单玄龙; 管宏图; 孙哲

    2012-01-01

    Taking oil sand reservoir in Upper Cretaceous of the western slope in Songliao Basin as an example , we found that the sand bodies of delta front are developed and the heterogeneity of oil sand reservoirs are serious in the study area. By comparison with conventional oil-gas reservoir, the in-layer heterogeneity is stronger than plane and interlayer heterogeneity even the controlling factors of oil sands reservoir heterogeneity are different. The prediction of hydrocarbon migration channels is based on the parameters of reservoir heterogeneity. The study results demonstrate that the lower part of underwater distributing channels and the coarse grain of mouth bars are the main migration channels on the background of simple slope structure without fault. The sand bodies of distal bars and sheet sands do not have the connectivity or hydrocarbon migration conditions because of mudstone barriers, in-terbeds, poor physics property and thin sandstone.%以松辽盆地西部斜坡上白垩统油砂矿藏为例的研究表明,研究区主要发育三角洲前缘储集砂体,油砂储层存在严重的非均质性.与常规油气储层相比,层内非均质性要比平面和层间非均质性强,并且其控制因素也存在差异.在此基础上,以储层非均质性参数对油气运移通道进行预测,认为在断层不发育的构造简单斜坡油气运移的主要通道为水下分流河道下部和河口坝中的粗粒砂体,而远砂坝和席状砂砂体由于泥岩隔层、夹层、物性差和砂体层薄的原因不具备砂体连通或油气运移的条件.

  18. Optimized recovery through cooperative geology and reservoir engineering

    Energy Technology Data Exchange (ETDEWEB)

    Craig, F.F. Jr.; Willcox, P.J.; Ballard, J.R.; Nation, W.R.

    1976-01-01

    Reservoir engineers have always used geological descriptions in their performance calculations. At first, the only information that could be utilized consisted of gross factors such as structure, thickness, fault and boundary locations, and the like, and average values for permeability, porosity, and fluid saturations. The advent of easy-to-use, relatively inexpensive mathematical models provided a new and powerful tool to the reservoir engineer for predicting performance. However, this tool required for its optimum use a more detailed reservoir description than geologists were accustomed to providing. Today's reservoir engineer utilizes the most detailed geological information along with a reservoir performance simulator to synthesize a detailed reservoir description capable of matching actual field performance data. Use of such a reservoir description permits the design of operating programs to obtain optimized recovery from hydrocarbon reservoirs. Two examples of the use of this combined geology-reservoir engineering technique are taken from the international arena of operations.

  19. Issues behind Competitiveness and Carbon Leakage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This report explores the vulnerability of heavy industry to carbon leakage and competitiveness loss. It reviews the existing literature on competitiveness and carbon leakage under uneven climate policies. It also suggests a statistical method to track carbon leakage, and applies this methodology to Phase I of the EU emissions trading scheme, for various industrial activities: iron and steel, cement, aluminium and refineries. Finally, it reviews measures to mitigate carbon leakage, as discussed in Australia, Canada, Europe, New Zealand and the US.

  20. A conceptual model for hydrocarbon accumulation and seepage processes inside Chapopote asphalt volcanism site, Southern Gulf of Mexico: from high resolution seismic point of view

    Science.gov (United States)

    Ding, F.; Spiess, V.; Fekete, N.; Keil, H.; Bohrmann, G.

    2007-05-01

    As part of the German R/V Meteor M67/2 expedition in 2006 to the southern Gulf of Mexico, a set of 2D high resolution seismic profiles was acquired across the Chapopote knoll to study sea floor asphalt occurrences and their origin. Based on regional seismic stratigraphy studies, correlated to DSDP sites, a higher reflective coarse grained sediment unit of Late Miocene age is identified as a potential shallow gas reservoir, overlain by a low permeability fine grained Pliocene and Pleistocene cover. As a result of salt diapirism, local uplift has caused reduced accumulation rates above the diaper since the late Pliocene, while the rates had been uniform throughout the area before. This has further improved the seal properties, since more fine grained material deposited in elevated locations. Nevertheless, on the crest of Chapopote, sediments above the coarse sediment unit are only around 150-75 m thick. Since oil and gas production can well be expected at depth in Jurassic and Tertiary source rocks, the presence of high amplitude reflector packages within the reservoir unit is interpreted as a result of the presence of hydrocarbons. This interpretation is further supported by the observation that some reflectors are cross-cutting and/or reveal a drop in instantaneous frequency. But, the thin seal above the reservoir unit, located directly underneath a widespread occurrence of asphalts at the sea floor, probably facilitates the leakage of hydrocarbons trapped inside the reservoir through a ~ 750 m wide acoustically chaotic zone partly aided by faulting. Since the top of Chapopote shows a high structural complexity, more seepage sites may exist beyond where seafloor asphalts have been found so far. Evolution and structure of the migration and reservoir system, which may be deep rooted, will be discussed both with respect to shallow gas and asphalt occurrences.

  1. Heat exchanger leakage problem location

    Directory of Open Access Journals (Sweden)

    Jícha Miroslav

    2012-04-01

    Full Text Available Recent compact heat exchangers are very often assembled from numerous parts joined together to separate heat transfer fluids and to form the required heat exchanger arrangement. Therefore, the leak tightness is very important property of the compact heat exchangers. Although, the compact heat exchangers have been produced for many years, there are still technological problems associated with manufacturing of the ideal connection between the individual parts, mainly encountered with special purpose heat exchangers, e.g. gas turbine recuperators. This paper describes a procedure used to identify the leakage location inside the prime surface gas turbine recuperator. For this purpose, an analytical model of the leaky gas turbine recuperator was created to assess its performance. The results obtained are compared with the experimental data which were acquired during the recuperator thermal performance analysis. The differences between these two data sets are used to indicate possible leakage areas.

  2. Electrolyte leakage as an indicator

    Directory of Open Access Journals (Sweden)

    ahmad nezami

    2009-06-01

    Full Text Available In order to evaluate the electrolyte leakage as an indicator of freezing injury in colza (Brassica napus L. genotypes under controlled conditions, a trial carried out at the green house of College of Agriculture, Ferdowsi University of Mashhad. In this study 10 rapeseed genotypes, with 5 temperatures (0, -4, -8, -12 and -16 °C on subplot and acclimation and non acclimation on main plot were evaluated on RCD factorial split plot with two replications. Plants were kept until 3-5 leaf stage in green house condition with 23/16 2 °C (day/night and natural photoperiod. Pots were subjected to acclimation (for three weeks or non acclimation that plants immediately frozen.For acclimation treatment after three weeks freezing was done in thermogradient freezer. The cell membrane integrity was measured through electrolyte leakage and the lethal temperature 50 (LT50 of samples also were determined. There were significant differences (p

  3. Heat exchanger leakage problem location

    Science.gov (United States)

    Hejčík, Jiří; Jícha, Miroslav

    2012-04-01

    Recent compact heat exchangers are very often assembled from numerous parts joined together to separate heat transfer fluids and to form the required heat exchanger arrangement. Therefore, the leak tightness is very important property of the compact heat exchangers. Although, the compact heat exchangers have been produced for many years, there are still technological problems associated with manufacturing of the ideal connection between the individual parts, mainly encountered with special purpose heat exchangers, e.g. gas turbine recuperators. This paper describes a procedure used to identify the leakage location inside the prime surface gas turbine recuperator. For this purpose, an analytical model of the leaky gas turbine recuperator was created to assess its performance. The results obtained are compared with the experimental data which were acquired during the recuperator thermal performance analysis. The differences between these two data sets are used to indicate possible leakage areas.

  4. Mechanism of Silurian Hydrocarbon Pool Formation in the Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    Liu Luofu; Guo Yongqiang; Zhao Yande; Li Yan; Chen Yuanzhuang; Chen Lixin; Pang Xiongqi; Xie Qilai; Huo Hong; Zhao Suping; Li Chao; Li Shuangwen

    2007-01-01

    There are three formation stages of Silurian hydrocarbon pools in the Tarim Basin. The widely distributed asphaltic sandstones in the Tazhong (central Tarim) and Tabei (northern Tarim) areas are the results of destruction of hydrocarbon pools formed in the first-stage, and the asphaltic sandstones around the Awati Sag were formed in the second-stage. The hydrocarbon migration characteristics reflected by the residual dry asphalts could represent the migration characteristics of hydrocarbons in the Silurian paleo-pools, while the present movable oil in the Silurian reservoirs is related to the later-stage (the third-stage) hydrocarbon accumulation.

  5. Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim (University of Texas at Austin, Austin, TX); Gilbert, Bob (University of Texas at Austin, Austin, TX); Lake, Larry W. (University of Texas at Austin, Austin, TX); Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett (University of Texas at Austin, Austin, TX); Thomas, Sunil G. (University of Texas at Austin, Austin, TX); Rightley, Michael J.; Rodriguez, Adolfo (University of Texas at Austin, Austin, TX); Klie, Hector (University of Texas at Austin, Austin, TX); Banchs, Rafael (University of Texas at Austin, Austin, TX); Nunez, Emilio J. (University of Texas at Austin, Austin, TX); Jablonowski, Chris (University of Texas at Austin, Austin, TX)

    2006-11-01

    The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging

  6. Quantification Of Leakage In Microvessels Using Entropy

    Science.gov (United States)

    Desoky, Ahmed H.; O'Connor, Carol; Harris, Patrick D.; Hall, Steven

    1989-05-01

    This paper describes the use of entropy to quantify leakage of large molecules in a microvascular system. This measure can be used as a global parameter to characterize leakage. A software package for analysis of a sequence of images comprising leakage in rat cremaster tissue has been developed. The analysis is based on the statistics of both gray level components and frequency components of the images. Results show that entropy provides a better measure of leakage because it does not depend on variation in illumination or translation and rotation of image objects. Moreover entropy based on frequency components provides a more sensitive leakage measure than entropy based on gray level components.

  7. Subsurface Barrier Formation as a CO2 Leakage Mitigation Technology

    Science.gov (United States)

    Castaneda Herrera, C. A.; Stevens, G.; Haese, R. R.

    2015-12-01

    Long-term CO2 containment in a geological storage reservoir is a key criterion for successfully implementing carbon capture and storage (CCS), however, CO2 leakage through different pathways cannot be completely ruled out in some instances. In this study we investigate the conditions for reactive barrier formation as a technology to mitigate and remediate CO2 leakage. We propose to inject a liquid reagent consistent of an alkaline sodium-silicate solution on top of the storage caprock, which will lead to silica mineral precipitation when in contact with an acidic, CO2-enriched fluid. This reaction will create a barrier that seals the leakage by reducing the permeability. Preliminary modelling has shown that the density, viscosity and alkalinity of the reagent fluid are critical for a successful seal formation, whereas differences in formation water composition and in the rock mineral composition are less important. In order to study the reaction through experiments, different reagent solutions were prepared and characterised in terms of silica concentration, density, viscosity and buffer capacity. In a static, diffusion-controlled batch experiment we observed silica mineral precipitation in the outer layer of the piece of rock inhibiting further mixing of the two fluids and slowing down the initial reaction rate. Core-flood experiments will be carried out to simulate barrier formation under fluid flow conditions. Here, the sealing efficiency of the reaction will be continuously measured in terms of a change in permeability.

  8. Characterization of hydrocarbon utilizing fungi from hydrocarbon ...

    African Journals Online (AJOL)

    Prof. Ogunji

    hydrocarbon polluted sediments and water .... ecosystem may result in selective increase or decrease in microbial population (Okpokwasili ... been implicated in degradation of hydrocarbons such as crude oil, polyaromatic hydrocarbons and.

  9. Petrophysical simulation in petroleum geology and reservoir engineering

    Energy Technology Data Exchange (ETDEWEB)

    Buryakovsky, L.; Chilingar, G. [Russian Academy of Natural Sciences, USA Branch, Los Angeles, CA (United States)

    2005-10-21

    The simulation of multivariate petrophysical relationships between core and well-log derived parameters on the example of the South Caspian Basin is discussed. For developing the petrophysical relationships, a number of deterministic and stochastic calculating procedures are used by the authors. These relationships are widely used in petroleum geology and reservoir engineering for hydrocarbon reserves estimation, reservoir description and simulation, field development planning, and reservoir production management. (author)

  10. Microseismic Monitoring of CO2 Injection at the Penn West Enhanced Oil Recovery Pilot Project, Canada: Implications for Detection of Wellbore Leakage

    Science.gov (United States)

    Martínez-Garzón, Patricia; Bohnhoff, Marco; Kwiatek, Grzegorz; Zambrano-Narváez, Gonzalo; Chalaturnyk, Rick

    2013-01-01

    A passive seismic monitoring campaign was carried out in the frame of a CO2-Enhanced Oil Recovery (EOR) pilot project in Alberta, Canada. Our analysis focuses on a two-week period during which prominent downhole pressure fluctuations in the reservoir were accompanied by a leakage of CO2 and CH4 along the monitoring well equipped with an array of short-period borehole geophones. We applied state of the art seismological processing schemes to the continuous seismic waveform recordings. During the analyzed time period we did not find evidence of induced micro-seismicity associated with CO2 injection. Instead, we identified signals related to the leakage of CO2 and CH4, in that seven out of the eight geophones show a clearly elevated noise level framing the onset time of leakage along the monitoring well. Our results confirm that micro-seismic monitoring of reservoir treatment can contribute towards improved reservoir monitoring and leakage detection. PMID:24002229

  11. Microseismic Monitoring of CO2 Injection at the Penn West Enhanced Oil Recovery Pilot Project, Canada: Implications for Detection of Wellbore Leakage

    Directory of Open Access Journals (Sweden)

    Gonzalo Zambrano-Narváez

    2013-09-01

    Full Text Available A passive seismic monitoring campaign was carried out in the frame of a CO2-Enhanced Oil Recovery (EOR pilot project in Alberta, Canada. Our analysis focuses on a two-week period during which prominent downhole pressure fluctuations in the reservoir were accompanied by a leakage of CO2 and CH4 along the monitoring well equipped with an array of short-period borehole geophones. We applied state of the art seismological processing schemes to the continuous seismic waveform recordings. During the analyzed time period we did not find evidence of induced micro-seismicity associated with CO2 injection. Instead, we identified signals related to the leakage of CO2 and CH4, in that seven out of the eight geophones show a clearly elevated noise level framing the onset time of leakage along the monitoring well. Our results confirm that micro-seismic monitoring of reservoir treatment can contribute towards improved reservoir monitoring and leakage detection.

  12. Microseismic monitoring of CO2 injection at the Penn West Enhanced Oil Recovery pilot project, Canada: implications for detection of wellbore leakage.

    Science.gov (United States)

    Martínez-Garzón, Patricia; Bohnhoff, Marco; Kwiatek, Grzegorz; Zambrano-Narváez, Gonzalo; Chalaturnyk, Rick

    2013-09-02

    A passive seismic monitoring campaign was carried out in the frame of a CO2-Enhanced Oil Recovery (EOR) pilot project in Alberta, Canada. Our analysis focuses on a two-week period during which prominent downhole pressure fluctuations in the reservoir were accompanied by a leakage of CO2 and CH4 along the monitoring well equipped with an array of short-period borehole geophones. We applied state of the art seismological processing schemes to the continuous seismic waveform recordings. During the analyzed time period we did not find evidence of induced micro-seismicity associated with CO2 injection. Instead, we identified signals related to the leakage of CO2 and CH4, in that seven out of the eight geophones show a clearly elevated noise level framing the onset time of leakage along the monitoring well. Our results confirm that micro-seismic monitoring of reservoir treatment can contribute towards improved reservoir monitoring and leakage detection.

  13. 30 CFR 250.1158 - How do I receive approval to downhole commingle hydrocarbons?

    Science.gov (United States)

    2010-07-01

    ... hydrocarbons? 250.1158 Section 250.1158 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE... hydrocarbons? (a) Before you perforate a well, you must request and receive approval from the Regional Supervisor to commingle hydrocarbons produced from multiple reservoirs within a common wellbore. The...

  14. Method for Hydrocarbon Detection Based on Theory of Multi-phase Medium

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A way is developed to detect hydrocarbon in accordance with BOlT theory and laboratory data,which is applied to several areas .The coincidence rate for hydrocarbon detection is higher than other sirnilar techniques. This method shows a good prospect for being widely used in hydrocarbon detecting at exploration stage and in reservoir monitoring at production stage.

  15. Indiana continent catheterizable urinary reservoir.

    Science.gov (United States)

    Castillo, O A; Aranguren, G; Campos-Juanatey, F

    2014-01-01

    Radical pelvic surgery requires continent or incontinent urinary diversion. There are many techniques, but the orthotopic neobladder is the most used. A continent catheterizable urinary reservoir is sometimes a good alternative when this derivation is not possible or not indicated. This paper has aimed to present our experience with the Indiana pouch continent urinary reservoir. The series is made up of 85 patients, 66 women and 19 men, with a mean age of 56 years (31-77 years). Variables analyzed were operating time, estimated blood loss, transfusion rate, hospital stay and peri-operatory complications. The main indication in 49 cases was resolution of complications related to the treatment of cervical cancer. Average operation time was 110.5 minutes (range 80-130 minutes). Mean blood loss was 450 cc (100-1000 cc). Immediate postoperative complications, all of which were treated medically, occurred in 16 patients (18.85%). One patient suffered anastomotic leakage. Hospital stay was 19 days (range 5-60 days) and there was no mortality in the series. Late complications occurred in 26 patients (32%), these being ureteral anastomotic stenosis in 11 cases, cutaneous stoma stenosis in 9 cases and reservoir stones in 6 cases. The Indiana continent catheterizable urinary reservoir is a valid option for the treatment of both urological and gynecological malignancies as well as for the management of pelvic morbidity related to the treatment of pelvic cancers. Copyright © 2013 AEU. Published by Elsevier Espana. All rights reserved.

  16. Apparatus for hydrocarbon extraction

    Science.gov (United States)

    Bohnert, George W.; Verhulst, Galen G.

    2013-03-19

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  17. Hydrocarbon accumulation model of the Cretaceous in southern China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Cretaceous in southern China is mainly a set of red and mauve clastic rock,with evaporation layers. For lack of source rock,it has been paid little attention to in the exploration process. With the development of research on hydrocarbon exploration,the masses of Cretaceous reservoirs and shows have been found in recent years. This means that the Cretaceous has great exploration potential. According to the research,authors find that the high-quality reservoir and efficient cap rocks develop in the Cretaceous. At the same time,the Cretaceous and underlying Paleozoic-Early Mesozoic marine strata and overlying Cenozoic nonmarine strata constitute a superimposed basin. Moreover,high-quality source rocks developed in the above-mentioned two sets of strata. In the south,especially in the middle and lower Yangtze region since the Himalayan strong rift was associated with a large number of faults,These faults connect the Cretaceous reservoir and its overlying and underlying source rocks,forming the fault-based and unconformity-based discontinuous source-reservoir-cap accumulation assemblages. Because the Cretaceous has the abundant oil and gas from Paleogene source rocks or Mesozoic–Paleozoic source rocks with secondary hydrocarbon generation ability,three types of reservoirs develop in the Cretaceous:"new-generating and old-reservoiring" reservoirs,"old-generating andnew-reservoiring" reservoirs,and few "self-generating andself-reservoiring" reservoirs. The hydrocarbon enrichment depends on two key factors. Firstly,Cretaceous reservoirs are near to the source kitchens,so its oil and gas source is ample. Secondly,the fault system is well developed,which provides the necessary conducting systems for hydrocarbon accumulation.

  18. Control of Formation of Lithological Reservoirs by Surrounding Mudstone

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Taking the Jiyang depression as an example, this paper discusses the control of the formation of lithological reservoir by surrounding rocks by integrated application of geological analysis, physical simulation, and the analysis of oil & gas accumulation mechanism. Geological statistical shows that the major burial depth and interval of lithological reservoirs in the Jiyang depression are related to the hydrocarbon generation in and expulsion from the Lower Tertiary source rocks and the time of the formation of most lithological reservoirs coincides with the peak of hydrocarbon generation and expulsion. The lithological traps located in the center of effective source rocks are propitious to high oil saturation than those located on the margin of effective source rocks. The hydrocarbon charge degree of the lithological reservoir has a positive correlation with the intensity of hydrocarbon expulsion from surrounding source rocks.Geological analyses and NMR experiments also show that the oil saturation of surrounding source rocks control the hydrocarbon potential of lithological traps, and a critical value for oil saturation of surrounding mudstone is required, that is, when the oil saturation of surrounding mudstone is lower than this critical value, no oil and gas accumulate in the lithological trap. The control of surrounding mudstone on the oil-bearing properties of lithological reservoirs is also analyzed by the mechanisms of hydrocarbon generation and expulsion as well as accumulation.

  19. The influence of geological data on the reservoir modelling and history matching process

    NARCIS (Netherlands)

    De Jager, G.

    2012-01-01

    For efficient production of hydrocarbons from subsurface reservoirs it is important to understand the spatial properties of the reservoir. As there is almost always too little information on the reservoir to build a representative model directly, other techniques have been developed for generating r

  20. The Importance of Water-Hydrocarbon Phase Equilibria During Reservoir Production and Drilling Operations Nouveaux défis liés à la présence d'équilibres eau-hydrocarbures lors des opérations de production et de forage

    Directory of Open Access Journals (Sweden)

    Zhou H.

    2006-12-01

    Full Text Available The inevitable presence of water in high pressure-high temperature reservoirs leads to a number of new challenges for petroleum engineers. A brief state of the art on water-hydrocarbon phase equilibria is presented. It appears that large amounts of water may be present in the hydrocarbon phase (up to 10% molar, and non negligible amounts of gas can dissolve in water. Based on experimental data, a large number of models have been developed. However, concerning the limitations of the data, caution is expressed about the correctness of some models. Recent studies have proven the usefulness of Henry's constants to predict hydrocarbon solubilities in water. The new challenges that are raised by this problem are discussed based on a number of recent publications. The water present in the hydrocarbon may lead to salt deposits downwell, and it must be taken into account in order to estimate the amount of gas in place. It can also result in modifications of the saturation pressure. Due to the presence of water, additional treatment is needed for pipe transport. On the other hand, the large amount of hydrocarbons dissolved in the water phase may result in a modification of the hydrocarbon composition, especially when reservoir pressure becomes very low. The increased toxicity of the water, containing either H2S or aromatics, can become a real burden for gas reservoirs in contact with aquifers or when disposing of production water. During drilling, large amounts of dissolved gas can become very hazardous, increasing the risk of eruption. A particular attention must be paid to acid gas injection in reservoirs, as the true effect of the injected gas may not be straightforward to predict. In conclusion, in light of the industrial importance of this information, some general guidelines are provided concerning additional data to be gathered and ideas for improving current models. La présence inévitable d'eau dans les réservoirs à hautes pression et temp

  1. Late-Stage Reservoir Formation Effect and Its Dynamic Mechanisms in Complex Superimposed Basins

    Institute of Scientific and Technical Information of China (English)

    KANG Dejiang; PANG Xiongqi; KUANG Jun; LUO Xiaorong; PANG Hong; LEI Lei

    2010-01-01

    Complex superimposed basins exhibit multi-stage tectonic events and multi-stage reservoir formation; hydrocarbon reservoirs formed in the early stage have generally late-stage genesis characteristics after undergoing adjustment,reconstruction and destruction of later-stage multiple tectonic events.In this paper,this phenomenon is called the late-stage reservoir formation effect.The late-stage reservoir formation effect is a basic feature of oil and gas-forming reservoirs in complex superimposed basins,revealing not only multi-stage character,relevance and complexity of oil and gas-forming reservoirs in superimposed basins but also the importance of late-stage reservoir formation.Late-stage reservoir formation is not a basic feature of off and gas forming reservoir in superimposed basins.Multi-stage reservoir formation only characterizes one aspect of oil and gas-forming reservoir in superimposed basins and does not represent fully the complexity of oil and gas-forming reservoir in superimposed basins.We suggest using"late-stage reservoir formation effect"to replace the"late-stage reservoir formation"concept to guide the exploration of complex reservoirs in superimposed basins.Under current geologic conditions,the late-stage reservoir formation effect is represented mainly by four basic forms:phase transformation,scale reconstruction,component variation and trap adjustment.The late-stage reservoir formation effect is produced by two kinds of geologic processes:first,the off and gas retention function of various geologic thresholds(hydrocarbon expulsion threshold,hydrocarbon migration threshold,and hydrocarbon accumulating threshold)causes the actual time of oil and gas reservoir formation to be later than the time of generation of large amounts of hydrocarbon in a conventional sense,producing the late-stage reservoir formation effect; second,multiple types of tectonic events(continuously strong reconstruction,early-stage strong reconstruction,middle-stage strong

  2. LEAKAGE OF COLONIC ANASTOMOSIS AFTER COLON RESECTION

    Institute of Scientific and Technical Information of China (English)

    Kanellos I; Pramateftakis MG

    2004-01-01

    Objective To present the diagnosis and management of anastomotic leakage after colon resection. Methods Early diagnosis and urgent therapeutic intervention are required in order to avert life-threatening conditions that may be caused by anastomotic leakage. Results The diagnosis of anastomotic leakage is based on clinical features, peripheral blood investigations and abdominal computed tomography (CT) scan. Major leaks are defined by symptoms of peritonitis and septicaemia due to leakage. Major leaks should be managed operatively. Minor leaks can be managed conservatively with successful outcomes. Conclusion Leakage of colonic anastomosis remains the most serious complication after colon resection. It is a major cause of postoperative morbidity and mortality. A high index of suspicion is required in order to detect early, nonspecific signs of a leakage and urgent surgical intervention is usually required to avert life-threatening events.

  3. Hydrocarbon provinces and productive trends in Libya and adjacent areas

    Energy Technology Data Exchange (ETDEWEB)

    Missallati, A.A. (Agip (N.A.M.E.)Ltd., Tripoli (Libya))

    1988-08-01

    According to the age of major reservoirs, hydrocarbon occurrences in Libya and adjacent areas can be grouped into six major systems which, according to their geographic locations, can be classified into two major hydrocarbon provinces: (1) Sirte-Pelagian basins province, with major reservoirs ranging from middle-late Mesozoic to early Tertiary, and (2) Murzog-Ghadames basins province, with major reservoirs ranging from early Paleozoic to early Mesozoic. In the Sirte-Pelagian basins province, hydrocarbons have been trapped in structural highs or in stratigraphic wedge-out against structural highs and in carbonate buildups. Here, hydrocarbon generation is characterized by the combined effect of abundant structural relief and reservoir development in the same hydrocarbon systems of the same age, providing an excellent example of hydrocarbon traps in sedimentary basins that have undergone extensive tensional fracturing in a shallow marine environment. In the Murzog-Ghadames basins province, hydrocarbons have been trapped mainly in structural highs controlled by paleostructural trends as basement arches which acted as focal points for oil migration and accumulation.

  4. Research of Temperature Tracer Method to Detect Tubular Leakage Passage in Earth-Dam

    Institute of Scientific and Technical Information of China (English)

    WANG Xin-jian; CHEN Jian-sheng

    2006-01-01

    The location, intensity and scope of concentrated leakage must be determined in order to repair earth-Dam scoured by the leakage. In this paper, firstly, heat tracer theory and distribution laws of temperature in soil body with leakage are discussed. Then temperature tracer model is established according to stable heat conduction theory. In such model, the concentrated seepage passage is simplified into a circular pipe as a boundary condition. The location, scope and flow-velocity of the concentrated leakage are estimated via ichnography of the lowest temperature based on temperature data from detecting wells by quantitative computation and qualitative analysis. In case study, the distribution characteristic of temperature (including temperature data of water in reservoir, drainage pipes and tail pond) can be interpreted by this model. A modified model is also set up, applied for detected data at different cross-sections of the leakage passage, in which the temperature data are rectified according to distances from data locations to calculating section. Finally, the model is solved by numerical iterative method, and the possible error of this theoretical model is discussed. The permeability coefficient in leakage area is identical with that of normal soil in magnitude after anti-seepage repairing accomplished, which indicates this model is effective.

  5. Leakage of CO2 from geologic storage: Role of secondaryaccumulation at shallow depth

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, K.

    2007-05-31

    Geologic storage of CO2 can be a viable technology forreducing atmospheric emissions of greenhouse gases only if it can bedemonstrated that leakage from proposed storage reservoirs and associatedhazards are small or can be mitigated. Risk assessment must evaluatepotential leakage scenarios and develop a rational, mechanisticunderstanding of CO2 behavior during leakage. Flow of CO2 may be subjectto positive feedbacks that could amplify leakage risks and hazards,placing a premium on identifying and avoiding adverse conditions andmechanisms. A scenario that is unfavorable in terms of leakage behavioris formation of a secondary CO2 accumulation at shallow depth. This paperdevelops a detailed numerical simulation model to investigate CO2discharge from a secondary accumulation, and evaluates the role ofdifferent thermodynamic and hydrogeologic conditions. Our simulationsdemonstrate self-enhancing as well as self-limiting feedbacks.Condensation of gaseous CO2, 3-phase flow of aqueous phase -- liquid CO2-- gaseous CO2, and cooling from Joule-Thomson expansion and boiling ofliquid CO2 are found to play important roles in the behavior of a CO2leakage system. We find no evidence that a subsurface accumulation of CO2at ambient temperatures could give rise to a high-energy discharge, aso-called "pneumatic eruption."

  6. Energy Conservation Through Duct Leakage Reduction

    Science.gov (United States)

    2004-02-26

    Energy Conservation Through Duct Leakage Reduction February 26, 2004 Rich Glatt – Lindab Inc. Report Documentation Page Form ApprovedOMB No. 0704...4. TITLE AND SUBTITLE Energy Conservation Through Duct Leakage Reduction 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...Wall – DW that installs like SW - easiest installing DW system on the market – Eliminates the need for costly flanged connections – SMACNA Leakage

  7. Reservoir-forming age and its exploration significance to stratigraphic reservoirs in southern Songliao Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Despite many studies concerning the forming age, evolution characteristics and the age of petroleum charging in the Fuxin upheaval of southern Songliao Basin, no consensus has been reached so far. This paper presents the first K-Ar dating of autogenetic illite from stratigraphic petroleum reservoirs in the Fuyu oil layer of the Fuxin upheaval belt. Isotopic test and age calculation were carried out based on the separation and purification of illite mineral, X-diffraction analysis and the detection of scanning electron microscopy. The evolution characteristics of structure, sedimentation, reservoir-forming about the Fuxin upheaval belt were interpreted in terms of the synthetical analysis of "six-type geological history" evolution in southern Songliao Basin. The geologic background of petroleum evolution and reservoir formation are similar in the entire central depression region of southern Songliao Basin. The Changling sag and the Fuxin upheaval belt brought about obvious upheaval-sag separation after the hydrocarbon-generation peak of K2qn1 and the main reservoir-forming period of the Fuyu oil layer, namely reservoir-forming happened before the Fuxin upheaval belt extensively raised. The reservoirs have three characteristics: the hydrocarbon source rock above the reservoir, the oil source in the locality, and the vertical migration. The geological cognition is corrected, that is, oil source came from the Changling sag and migrated from the side direction. The bulk process of petroleum charging in the stratigraphic hydrocarbon reservoirs in the Fuxin upheaval belt of southern Songliao Basin is determined according to the isotopic age of autogenetic illite in combination with the method of fluid inclusions. The cognition is helpful to exactly evaluate the resource potential and exploration direction in the Fuxin upheaval belt, Changling sag and their peripheral areas. The present results indicate that the combination of the two methods (the K-Ar dating of

  8. Practical Leakage-Resilient Symmetric Cryptography

    DEFF Research Database (Denmark)

    Faust, Sebastian; Pietrzak, Krzysztof; Schipper, Joachim

    2012-01-01

    -adaptively. For example, we show that a three round Feistel network instantiated with a leakage resilient PRF yields a leakage resilient PRP if the inputs are chosen non-adaptively (This complements the result of Dodis and Pietrzak [CRYPTO’10] who show that if a adaptive queries are allowed, a superlogarithmic number...... of rounds is necessary.) We also show that a minor variation of the classical GGM construction gives a leakage resilient PRF if both, the leakage-function and the inputs, are chosen non-adaptively...

  9. Leakage-current properties of encapsulants

    Science.gov (United States)

    Wen, L. C.

    A theoretical modeling of leakage current in ethylene vinyl acetate (EVA) and polyvinyl butyral (PVB) modules is being developed and is described. The modeling effort derives mathematical relationships for the bulk and surface conductivites of EVA and PVB, the surface conductivities of glass and polymeric films, and the EVA and PVB pottants, all as functions of environmental parameters. Results from the modeling indicate that for glass/EVA, the glass surface controls the interfacial conductivity, although EVA bulk conductivity controls total leakage current. For PVB/glass, the interface conductivity controls leakage currents for relative humidity (RH) less than 40 to 50%, but PVB bulk conductivity controls leakage current above 50% RH.

  10. Improving stopping construction to minimize leakage.

    Science.gov (United States)

    Grau, Roy H; Mazzella, Andrew L; Martikainen, Anu L

    2012-07-01

    The proper sealing of stoppings is an important step in reducing leakage from the intake to the return airways. Leakage and the subsequent loss of ventilation resulting from improperly sealed stoppings can lead to unhealthy and unsafe working conditions. The research presented in this paper investigates the total leakage of a stopping, including air leakage through the stopping, at the stopping perimeter, and through the coalbed. The study also examines sealing considerations for stoppings that are constructed under roof control screen, the effects that wooden wedges had on inhibiting efficient application of polyurethane foam sealant, and airflow leakage through the surrounding coal. The work involved building a stopping in a dead end room of the NIOSH Safety Research Coal Mine and then pressurising the room using compressed air. Stopping leakage was evaluated by measuring air pressure loss in the enclosed room due to the air leakage. Part of the research utilises a diluted soap solution that was applied to the stopping and the surrounding coal to detect air leakage signified by bubble formations. The results show that stopping leakage can be minimised with proper sealing.

  11. Degradation of benzene and other aromatic hydrocarbons by anaerobic bacteria

    NARCIS (Netherlands)

    Weelink, S.A.B.

    2008-01-01

    Accidental spills, industrial discharges and gasoline leakage from underground storage tanks have resulted in serious pollution of the environment with monoaromatic hydrocarbons, such as benzene, toluene, ethylbenzene and xylene (so-called BTEX). High concentrations of BTEX have been detected in soi

  12. Degradation of benzene and other aromatic hydrocarbons by anaerobic bacteria

    NARCIS (Netherlands)

    Weelink, S.A.B.

    2008-01-01

    Accidental spills, industrial discharges and gasoline leakage from underground storage tanks have resulted in serious pollution of the environment with monoaromatic hydrocarbons, such as benzene, toluene, ethylbenzene and xylene (so-called BTEX). High concentrations of BTEX have been detected in soi

  13. Equilibrium composition between liquid and clathrate reservoirs on Titan

    CERN Document Server

    Mousis, Olivier; Lunine, Jonathan I; Sotin, Christophe

    2015-01-01

    Hundreds of lakes and a few seas of liquid hydrocarbons have been observed by the Cassini spacecraft to cover the polar regions of Titan. A significant fraction of these lakes or seas could possibly be interconnected with subsurface liquid reservoirs of alkanes. In this paper, we investigate the interplay that would happen between a reservoir of liquid hydrocarbons located in Titan's subsurface and a hypothetical clathrate reservoir that progressively forms if the liquid mixture diffuses throughout a preexisting porous icy layer. To do so, we use a statistical-thermodynamic model in order to compute the composition of the clathrate reservoir that forms as a result of the progressive entrapping of the liquid mixture. This study shows that clathrate formation strongly fractionates the molecules between the liquid and the solid phases. Depending on whether the structure I or structure II clathrate forms, the present model predicts that the liquid reservoirs would be mainly composed of either propane or ethane, r...

  14. Petroleum reservoir engineering - a personal perspective

    Energy Technology Data Exchange (ETDEWEB)

    Archer, J.S. [Imperial Coll. of Science and Technology, London (United Kingdom)

    1996-12-31

    This paper was invited as part of the Ad 1995 - NW Europe`s Hydrocarbon Industry Symposium to mark Aberdeen University`s 500th Anniversay. The author has been taken the opportunity to recall, from a highly personal and selective perspective, some of the events of the last 25 years in reservoir engineering, through his own experiences of North Sea fields. The first part of the paper sets the background to reservoir engineering through some of the key contributions to the literature. The second part recalls the early North Sea reservoir planning and the emergence of multidisciplinary approaches to reservoir characterization and asset management. The third part of the paper focuses on reservoir engineering research at Imperial College, and the final part poses a number of questions on the future of reservoir engineering in a UK North Sea context. The author does not intend to provide a critical appraisal of the reservoir engineering literature that has emerged in the last 25 years, therefore, the reservoir engineering with which the author has been most closely associated naturally receives the greatest prominence in a paper of this type. In no way should this be construed as a claim to invention. (author)

  15. Estimating leakage from forest carbon sequestration programs

    Energy Technology Data Exchange (ETDEWEB)

    Murray, B.C. [RTI International, Research Triangle Park, NC (United States); McCarl, B.A. [Texas A and M Univ., College Station, TX (United States). Dept. of Agricultural Economics; Lee, H.C. [Western Ontario Univ., London, ON (Canada). Dept. of Economics

    2003-03-01

    Nearly half of all terrestrial carbon is stored in forest ecosystems. Land use changes such as deforestation were responsible for nearly 20 per cent of carbon dioxide (CO{sub 2}) released in the atmosphere worldwide between 1989 to 1998. This paper developed an estimation procedure that addressed the magnitude of potential leakage from carbon sequestration projects in the forest sector, including the conversion of land from agriculture to forest. Leakage occurs when a program's direct carbon benefits are undermined by carbon releases elsewhere. Leakage directly undermines greenhouse gas (GHG) emission reducing actions and should be considered when designing and evaluating policies. Leakage should be deducted from the carbon credits granted to mitigation projects, and accounting rules and guidelines for crediting carbon sequestration projects. Analytic, econometric, and sector-level optimization models were combined to estimate leakage from different forest carbon sequestration activities. The FASOM forest and agricultural sector model was used to investigate empirical leakage consequences in 4 categories: forest setasides, avoided deforestation, afforestation, and a combination of afforestation and avoided deforestation. The interaction of market forces that cause leakage from forest sector projects was investigated. Results suggested that leakage from geographically targeted mitigation projects can be sizeable. For small projects, leakage tends to be larger in proportion to direct project benefits than larger programs or policies. It was suggested that if leakage is more pronounced in forest carbon projects than energy sector projects, this could affect the terms of trade for the credits generated by different sources and thereby affect the optimal portfolio of mitigation options. It was concluded that policy designers and market makers should account for leakage effects when enabling exchanges of GHG offsets.

  16. Hydrogeology from 10,000 ft below: lessons learned in applying pulse testing for leakage detection in a carbon sequestration formation

    Science.gov (United States)

    Sun, A. Y.; Lu, J.; Hovorka, S. D.; Freifeld, B. M.; Islam, A.

    2015-12-01

    Monitoring techniques capable of deep subsurface detection are desirable for early warning and leakage pathway identification in geologic carbon storage formations. This work investigates the feasibility of a leakage detection technique based on pulse testing, which is a traditional hydrogeological characterization tool. In pulse testing, the monitoring reservoir is stimulated at a fixed frequency and the acquired pressure perturbation signals are analyzed in the frequency domain to detect potential deviations in the reservoir's frequency domain response function. Unlike traditional time-domain analyses, the frequency-domain analysis aims to minimize the interference of reservoir noise by imposing coded injection patterns such that the reservoir responses to injection can be uniquely determined. We have established the theoretical basis of the approach in previous work. Recently, field validation of this pressure-based, leakage detection technique was conducted at a CO2-EOR site located in Mississippi, USA. During the demonstration, two sets of experiments were performed using 90-min and 150-min pulsing periods, for both with and without leak scenarios. Because of the lack of pre-existing leakage pathways, artificial leakage CO2 was simulated by rate-controlled venting from one of the monitoring wells. Our results show that leakage events caused a significant deviation in the amplitude of the frequency response function, indicating that pulse testing may be used as a cost-effective monitoring technique with a strong potential for automation.

  17. Forest Carbon Leakage Quantification Methods and Their Suitability for Assessing Leakage in REDD

    Directory of Open Access Journals (Sweden)

    Sabine Henders

    2012-01-01

    Full Text Available This paper assesses quantification methods for carbon leakage from forestry activities for their suitability in leakage accounting in a future Reducing Emissions from Deforestation and Forest Degradation (REDD mechanism. To that end, we first conducted a literature review to identify specific pre-requisites for leakage assessment in REDD. We then analyzed a total of 34 quantification methods for leakage emissions from the Clean Development Mechanism (CDM, the Verified Carbon Standard (VCS, the Climate Action Reserve (CAR, the CarbonFix Standard (CFS, and from scientific literature sources. We screened these methods for the leakage aspects they address in terms of leakage type, tools used for quantification and the geographical scale covered. Results show that leakage methods can be grouped into nine main methodological approaches, six of which could fulfill the recommended REDD leakage requirements if approaches for primary and secondary leakage are combined. The majority of methods assessed, address either primary or secondary leakage; the former mostly on a local or regional and the latter on national scale. The VCS is found to be the only carbon accounting standard at present to fulfill all leakage quantification requisites in REDD. However, a lack of accounting methods was identified for international leakage, which was addressed by only two methods, both from scientific literature.

  18. The Silurian Reservoir Bed-Differentiated Asphalts in Tarim Basin and Modeling Experiments on Their Origin

    Institute of Scientific and Technical Information of China (English)

    刘洛夫; 刘宏江; 王洪玉; 曾溅辉

    2002-01-01

    There is a type of asphalt that originated from differentiation from reservoir bed (named reservoir bed-differentiated asphalt) in the Silurian asphaltic sandstones of the Tarim Basin. These asphalts are the result of second-time charging of hydrocarbons into the Silurian reservoir, which were derived from Lower Paleozoic source rocks. Asphalt was differentiated from the reservoir bed in the hydrocarbon gathering area of secondary migration. The differen tiation is caused by changes in reservoir physical properties when pearl or chain hydrocarbons migrating through and gathering in the reservoir bed, and light components are lost and heavy ones are involved in the formation of asphalt or heavy oil. There are two kinds of occurrence of these asphalts in the Silurian system of the Tarim Basin. One is the poor heavy oil layer with lower oil saturation in trap and the other is scattered hydrocarbon distributed along the transport layer and unconformity surface. Reservoir bed-differentiated asphalts have two characteristics: total hydrocarbon content is high in extractable organic matter and the ratio of saturated to aromatic hydrocarbon is usually greater than unity. The physically modeling experiment has confirmed these characteristics and the genesis of the reservoir bed-differentiated asphalts.

  19. The Silurian Reservoir Bed—Differentiated Asphalts in Tarim Basin and Modeling Experiments on Their Origin

    Institute of Scientific and Technical Information of China (English)

    刘洛夫; 刘宏江; 等

    2002-01-01

    There is a type of asphalt that originated from differentiation from reservoir bed (named reservoir bed-differentiated asphalt)in the Silurian asphaltic sandstones of the Tarim Basin.These asphalts are the result of second-time charging of hydrocarbons into the Silurian reservoir,which were derived from Lower Paleozoic source rocks.Asphalt was differentiated from the reservoir bed in the hydrocarbon gathering area of secondary migration.The different-tiation is caused by changes in reservoir physical properties when pearl or chain hydrocarbons migrating through and gathering in the reservoir bed,and light components are lost and heavy ones are involved in the formation of asphalt or heavy oil.There are two kinds of occurrence of these asphalts in the Silurian system of the Tarim Basin.One is the poor heavy oil layer with lower oil saturation in trap and the other is scattered hydrocarbon distributed along the trans-port layer and unconformity surface.Reservoir bed-differentiated asphalts have two characteris-tics:total hydrocarbon content is high in extractable organic matter and the ratio of saturated to aromatic hydrocarbon is usually greater than unity.The physically modeling experiment has confirmed these characteristics and the genesis of the reservoir bed-differentiated asphalts.

  20. 储层沥青成因及其对油气运聚的影响——以鄂尔多斯盆地华庆地区长8油层组1砂组为例%Reservoir bitumen genesis and its impacts on hydrocarbon migration and accumulation:a case study from Chang 81 of Yangchang Fomation in Huaqing area, the Ordos Basin

    Institute of Scientific and Technical Information of China (English)

    陈世加; 姚泾利; 路俊刚; 杨国平; 文延春; 张纪智; 石正灏

    2012-01-01

    Bitumen is common in the pores of Chang 8 pay zone of the Triassic Yanchang Formation in Huaqing area of the central part of Ordos Basin, and the oil-water relationship is very complicated. According to the analysis on the geochemical characteristics of reservoir extracts and crude oil, combining with comparative test on the reservoir physical property of cores containing bitumen before and after washing oil and the reservoir fluorescence analysis, authors studies in detail the reservoir bitumen genesis and its impact on reservoir physical property and hydrocarbon migration and accumulation in this area. The results show that the genesis of reservoir bitumen and crude oil are different, and the bitumen has lower maturity with strong biodegradation. Base on the experiment of washing oil, it is found that both the post-washing porosity and permeability of cores containing bitumen increase significantly, and the oil formed in late stage mainly distributes in the residual pore filled with bitumen. It is pointed out that bitumen has an important control on reservoir physical property and hydrocarbon migration andaccumulation at late stage. The Chang 81 formation experienced hydrocarbon two accumulation stages,the first stage happened in Middle-Late Jurassic and the second in Early Cretaceous. The early accumulated crude oil with low maturity suffered from strong biodegradation and were turned to bitumen,which filled in the pores of reservoir together with chlorites and ferrocalcites, making the reservoir tighter. The mature oil generated from the source rocks in late stage could only accumulate in the residual pores filled with bitumen or in pores of reservoir with less bitumen.%鄂尔多斯盆地中部华庆地区三叠系延长组长8油层组1砂组储层孔隙中普遍见沥青,油水关系十分复杂.通过对储层抽提物和原油的地球化学特征分析,并结合含沥青岩心洗油前后储层物性对比实验和储层显微荧光分析,系统研究了

  1. Application of Electrical Resistivity Tomography Technique for Characterizing Leakage Problem in Abu Baara Earth Dam, Syria

    Directory of Open Access Journals (Sweden)

    Walid Al-Fares

    2014-01-01

    Full Text Available Electrical Resistivity Tomography (ERT survey was carried out at Abu Baara earth dam in northwestern Syria, in order to delineate potential pathways of leakage occurring through the subsurface structure close to the dam body. The survey was performed along two straight measuring profiles of 715 and 430 m length in up- and downstream sides of the dam’s embankment. The analysis of the inverted ERT sections revealed the presence of fractured and karstified limestone rocks which constitute the shallow bedrock of the dam reservoir. Several subsurface structural anomalies were identified within the fractured bedrock, most of which are associated with probable karstic cavities, voids, and discontinuity features developed within the carbonates rocks. Moreover, results also showed the occurrence of a distinguished subsiding structure coinciding with main valley course. Accordingly, it is believed that the bedrock and the other detected features are the main potential causes of water leakage from the dam’s reservoir.

  2. Quantifying Information Leakage of Randomized Protocols

    DEFF Research Database (Denmark)

    Biondi, Fabrizio; Wasowski, Andrzej; Legay, Axel

    2013-01-01

    The quantification of information leakage provides a quantitative evaluation of the security of a system. We propose the usage of Markovian processes to model and analyze the information leakage of deterministic and probabilistic systems. We show that this method generalizes the lattice of inform...... and non-timed attacks on the Onion Routing protocol....

  3. Predicting Envelope Leakage in Attached Dwellings

    Energy Technology Data Exchange (ETDEWEB)

    Faakye, O.; Arena, L.; Griffiths, D.

    2013-07-01

    The most common method for measuring air leakage is to use a single blower door to pressurize and/or depressurize the test unit. In detached housing, the test unit is the entire home and the single blower door measures air leakage to the outside. In attached housing, this 'single unit', 'total', or 'solo' test method measures both the air leakage between adjacent units through common surfaces as well air leakage to the outside. Measuring and minimizing this total leakage is recommended to avoid indoor air quality issues between units, reduce energy losses to the outside, reduce pressure differentials between units, and control stack effect. However, two significant limitations of the total leakage measurement in attached housing are: for retrofit work, if total leakage is assumed to be all to the outside, the energy benefits of air sealing can be significantly over predicted; for new construction, the total leakage values may result in failing to meet an energy-based house tightness program criterion. The scope of this research is to investigate an approach for developing a viable simplified algorithm that can be used by contractors to assess energy efficiency program qualification and/or compliance based upon solo test results.

  4. Radiofrequency radiation leakage from microwave ovens.

    Science.gov (United States)

    Lahham, Adnan; Sharabati, Afifeh

    2013-12-01

    This work presents data on the amount of radiation leakage from 117 microwave ovens in domestic and restaurant use in the West Bank, Palestine. The study of leakage is based on the measurements of radiation emissions from the oven in real-life conditions by using a frequency selective field strength measuring system. The power density from individual ovens was measured at a distance of 1 m and at the height of centre of door screen. The tested ovens were of different types, models with operating powers between 1000 and 1600 W and ages ranging from 1 month to >20 y, including 16 ovens with unknown ages. The amount of radiation leakage at a distance of 1 m was found to vary from 0.43 to 16.4 μW cm(-2) with an average value equalling 3.64 μW cm(-2). Leakages from all tested microwave ovens except for seven ovens (∼6 % of the total) were below 10 μW cm(-2). The highest radiation leakage from any tested oven was ∼16.4 μW cm(-2), and found in two cases only. In no case did the leakage exceed the limit of 1 mW cm(-2) recommended by the ICNIRP for 2.45-GHz radiofrequency. This study confirms a linear correlation between the amount of leakage and both oven age and operating power, with a stronger dependence of leakage on age.

  5. Leakage-resilient cryptography from minimal assumptions

    DEFF Research Database (Denmark)

    Hazay, Carmit; López-Alt, Adriana; Wee, Hoeteck;

    2013-01-01

    We present new constructions of leakage-resilient cryptosystems, which remain provably secure even if the attacker learns some arbitrary partial information about their internal secret key. For any polynomial ℓ, we can instantiate these schemes so as to tolerate up to ℓ bits of leakage. While the...

  6. Markovian Processes for Quantitative Information Leakage

    DEFF Research Database (Denmark)

    Biondi, Fabrizio

    and randomized processes with Markovian models and to compute their information leakage for a very general model of attacker. We present the QUAIL tool that automates such analysis and is able to compute the information leakage of an imperative WHILE language. Finally, we show how to use QUAIL to analyze some...

  7. basement reservoir geometry and properties

    Science.gov (United States)

    Walter, bastien; Geraud, yves; Diraison, marc

    2017-04-01

    Basement reservoirs are nowadays frequently investigated for deep-seated fluid resources (e.g. geothermal energy, groundwater, hydrocarbons). The term 'basement' generally refers to crystalline and metamorphic formations, where matrix porosity is negligible in fresh basement rocks. Geothermal production of such unconventional reservoirs is controlled by brittle structures and altered rock matrix, resulting of a combination of different tectonic, hydrothermal or weathering phenomena. This work aims to characterize the petro-structural and petrophysical properties of two basement surface analogue case studies in geological extensive setting (the Albert Lake rift in Uganda; the Ifni proximal margin of the South West Morocco Atlantic coast). Different datasets, using field structural study, geophysical acquisition and laboratory petrophysical measurements, were integrated to describe the multi-scale geometry of the porous network of such fractured and weathered basement formations. This study points out the multi-scale distribution of all the features constituting the reservoir, over ten orders of magnitude from the pluri-kilometric scale of the major tectonics structures to the infra-millimetric scale of the secondary micro-porosity of fractured and weathered basements units. Major fault zones, with relatively thick and impermeable fault core structures, control the 'compartmentalization' of the reservoir by dividing it into several structural blocks. The analysis of these fault zones highlights the necessity for the basement reservoirs to be characterized by a highly connected fault and fracture system, where structure intersections represent the main fluid drainage areas between and within the reservoir's structural blocks. The suitable fluid storage areas in these reservoirs correspond to the damage zone of all the fault structures developed during the tectonic evolution of the basement and the weathered units of the basement roof developed during pre

  8. Leakage-Resilient Circuits without Computational Assumptions

    DEFF Research Database (Denmark)

    Dziembowski, Stefan; Faust, Sebastian

    2012-01-01

    Physical cryptographic devices inadvertently leak information through numerous side-channels. Such leakage is exploited by so-called side-channel attacks, which often allow for a complete security breache. A recent trend in cryptography is to propose formal models to incorporate leakage into the ......Physical cryptographic devices inadvertently leak information through numerous side-channels. Such leakage is exploited by so-called side-channel attacks, which often allow for a complete security breache. A recent trend in cryptography is to propose formal models to incorporate leakage...... into the model and to construct schemes that are provably secure within them. We design a general compiler that transforms any cryptographic scheme, e.g., a block-cipher, into a functionally equivalent scheme which is resilient to any continual leakage provided that the following three requirements are satisfied...

  9. Climate Policy and Carbon Leakage

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    This report explores the effects of the EU emissions trading scheme on the aluminium sector (i.e. competitiveness loss and carbon leakage). With its very high electricity intensity, primary aluminium stands out in the heavy industry picture: a sector whose emissions are not capped in the present EU ETS, European aluminium smelters still stand to lose profit margins and, possibly, market shares, as electricity prices increase following CO2 caps on generators' emissions - the famous pass-through of CO2 prices into electricity prices. The analysis includes a method of quantification of this issue, based on two indicators: profit margins and trade flows. As the EU is at the forefront of such policy, the paper provides policy messages to all countries on how trade exposed energy-intensive industries can be 'moved' by carbon constraint. This also is a contentious topic in Australia, Japan, New Zealand, and the US, where ambitious climate policies -- including cap-and-trade systems -- are currently debated.

  10. T2Well/ECO2N Version 1.0: Multiphase and Non-Isothermal Model for Coupled Wellbore-Reservoir Flow of Carbon Dioxide and Variable Salinity Water

    Energy Technology Data Exchange (ETDEWEB)

    Pan, L.; Oldenburg, C.M.; Wu, Y.-S.; Pruess, K.

    2011-02-14

    At its most basic level, the injection of CO{sub 2} into geologic CO{sub 2} storage sites involves a system comprising the wellbore and the target reservoir. The wellbore is the only conduit available to emplace CO{sub 2} into reservoirs for long-term storage. At the same time, wellbores in general have been identified as the most likely conduit for CO{sub 2} and brine leakage from geologic carbon sequestration (GCS) sites, especially those in sedimentary basins with historical hydrocarbon production. We have developed a coupled wellbore and reservoir model for simulating the dynamics of CO{sub 2} injection and leakage through wellbores. The model describes the following processes: (1) upward or downward wellbore flow of CO{sub 2} and variable salinity water with transition from supercritical to gaseous CO{sub 2} including Joule-Thomson cooling, (2) exsolution of CO{sub 2} from the aqueous phase as pressure drops, and (3) cross flow into or interaction with layers of surrounding rock (reservoirs). We use the Drift-Flux Model and related conservation equations for describing transient two-phase non-isothermal wellbore flow of CO{sub 2}-water mixtures under different flow regimes and interacting with surrounding rock. The mass and thermal energy balance equations are solved numerically by a finite difference scheme with wellbore heat transmission to the surrounding rock handled either semi-analytically or numerically. The momentum balance equation for the flow in the wellbore is solved numerically with a semi-explicit scheme. This manual provides instructions for compilation and use of the new model, and presents some example problems to demonstrate its use.

  11. MULTIDISCIPLINARY IMAGING OF ROCK PROPERTIES IN CARBONATE RESERVOIRS FOR FLOW-UNIT TARGETING

    Energy Technology Data Exchange (ETDEWEB)

    Stephen C. Ruppel

    2005-02-01

    Despite declining production rates, existing reservoirs in the US contain large quantities of remaining oil and gas that constitute a huge target for improved diagnosis and imaging of reservoir properties. The resource target is especially large in carbonate reservoirs, where conventional data and methodologies are normally insufficient to resolve critical scales of reservoir heterogeneity. The objectives of the research described in this report were to develop and test such methodologies for improved imaging, measurement, modeling, and prediction of reservoir properties in carbonate hydrocarbon reservoirs. The focus of the study is the Permian-age Fullerton Clear Fork reservoir of the Permian Basin of West Texas. This reservoir is an especially appropriate choice considering (a) the Permian Basin is the largest oil-bearing basin in the US, and (b) as a play, Clear Fork reservoirs have exhibited the lowest recovery efficiencies of all carbonate reservoirs in the Permian Basin.

  12. Estimation of reservoir fluid volumes through 4-D seismic analysis on Gullfaks

    Energy Technology Data Exchange (ETDEWEB)

    Veire, H.S.; Reymond, S.B.; Signer, C.; Tenneboe, P.O.; Soenneland, L.; Schlumberger, Geco-Prakla

    1998-12-31

    4-D seismic has the potential to monitor hydrocarbon movement in reservoirs during production, and could thereby supplement the predictions of reservoir parameters offered by the reservoir simulator. However 4-D seismic is often more band limited than the vertical resolution required in the reservoir model. As a consequence the seismic data holds a composite response from reservoir parameter changes during production so that the inversion becomes non-unique. A procedure where data from the reservoir model are integrated with seismic data will be presented. The potential of such a procedure is demonstrated through a case study from a recent 4-D survey over the Gullfaks field. 2 figs.

  13. Experimental evaluation of clinical colon anastomotic leakage

    DEFF Research Database (Denmark)

    Pommergaard, Hans-Christian

    2014-01-01

    has been improved and is now thoroughly validated. If used by researchers worldwide, comparison of results is possible. Pure ischemia/anoxia may be too simple an approach to create a clinical leakage model. Thus, future models could focus on multiple risk factors. Conclusively, large-scale clinical...... mice. The number of sutures in the intervention group was reduced to produce a suitable leakage rate. Moreover, the analgesia and suture material were changed in order to optimize the model. In the final experiment, the four-suture anastomoses resulted in a 40% leakage rate in the intervention groups...

  14. Calculation of Leakage Inductance for High Frequency Transformers

    DEFF Research Database (Denmark)

    Ouyang, Ziwei; Jun, Zhang; Hurley, William Gerard

    2015-01-01

    Frequency dependent leakage inductance is often observed. High frequency eddy current effects cause a reduction in leakage inductance. The proximity effect between adjacent layers is responsible for the reduction of leakage inductance. This paper gives a detailed analysis of high frequency leakage...... inductance and proposes an accurate prediction methodology. High frequency leakage inductances in several interleaved winding configurations are also discussed. Interleaved winding configurations actually give a smaller degree of reduction of leakage induction at high frequency. Finite Element Analysis (FEA...

  15. The hydrocarbon sphere

    Energy Technology Data Exchange (ETDEWEB)

    Mandev, P.

    1984-01-01

    The hydrocarbon sphere is understood to be the area in which hydrocarbon compounds are available. It is believed that the lower boundary on the hydrocarbon sphere is most probably located at a depth where the predominant temperatures aid in the destruction of hydrocarbons (300 to 400 degrees centigrade). The upper limit on the hydrocarbon sphere obviously occurs at the earth's surface, where hydrocarbons oxidize to H20 and CO2. Within these ranges, the occurrence of the hydrocarbon sphere may vary from the first few hundred meters to 15 kilometers or more. The hydrocarbon sphere is divided into the external (mantle) sphere in which the primary gas, oil and solid hydrocarbon fields are located, and the internal (metamorphic) sphere containing primarily noncommercial accumulations of hydrocarbon gases and solid carbon containing compounds (anthraxilite, shungite, graphite, etc.) based on the nature and scale of hydrocarbon compound concentrations (natural gas, oil, maltha, asphalt, asphaltite, etc.).

  16. On leakage and seepage from geological carbon sequestration sites

    Energy Technology Data Exchange (ETDEWEB)

    Oldenburg, C.M.; Unger, A.J.A.; Hepple, R.P.; Jordan, P.D.

    2002-07-18

    Geologic carbon sequestration is one strategy for reducing the rate of increase of global atmospheric carbon dioxide (CO{sub 2} ) concentrations (IEA, 1997; Reichle, 2000). As used here, the term geologic carbon sequestration refers to the direct injection of supercritical CO{sub 2} deep into subsurface target formations. These target formations will typically be either depleted oil and gas reservoirs, or brine-filled permeable formations referred to here as brine formations. Injected CO{sub 2} will tend to be trapped by one or more of the following mechanisms: (1) permeability trapping, for example when buoyant supercritical CO{sub 2} rises until trapped by a confining caprock; (2) solubility trapping, for example when CO{sub 2} dissolves into the aqueous phase in water-saturated formations, or (3) mineralogic trapping, such as occurs when CO{sub 2} reacts to produce stable carbonate minerals. When CO{sub 2} is trapped in the subsurface by any of these mechanisms, it is effectively sequestered away from the atmosphere where it would otherwise act as a greenhouse gas. The purpose of this report is to summarize our work aimed at quantifying potential CO{sub 2} seepage due to leakage from geologic carbon sequestration sites. The approach we take is to present first the relevant properties of CO{sub 2} over the range of conditions from the deep subsurface to the vadose zone (Section 2), and then discuss conceptual models for how leakage might occur (Section 3). The discussion includes consideration of gas reservoir and natural gas storage analogs, along with some simple estimates of seepage based on assumed leakage rates. The conceptual model discussion provides the background for the modeling approach wherein we focus on simulating transport in the vadose zone, the last potential barrier to CO{sub 2} seepage (Section 4). Because of the potentially wide range of possible properties of actual future geologic sequestration sites, we carry out sensitivity analyses by

  17. APPLICATION OF WELL LOG ANALYSIS IN ASSESSMENT OF PETROPHYSICAL PARAMETERS AND RESERVOIR CHARACTERIZATION OF WELLS IN THE “OTH” FIELD, ANAMBRA BASIN, SOUTHERN NIGERIA

    Directory of Open Access Journals (Sweden)

    Eugene URORO

    2014-12-01

    Full Text Available Over the past years, the Anambra basin one of Nigeria’s inland basins has recorded significant level of hydrocarbon exploration activities. The basin has been confirmed by several authors from source rock analyses to have the potential for generating hydrocarbon. For the hydrocarbon to be exploited, it is imperative to have a thorough understanding of the reservoir. Computer-assisted log analyses were employed to effectively evaluate the petrophysical parameters such as the shale volume (Vsh, total porosity (TP, effective porosity (EP, water saturation (Sw, and hydrocarbon saturation (Sh. Cross-plots of the petrophysical parameters versus depth were illustrated. Five hydrocarbon bearing reservoirs were delineated in well 1, four in well 2. The reservoirs in well 3 do not contain hydrocarbon. The estimated reservoir porosity varies from 10% to 21% while their permeability values range from 20md to 1400md. The porosity and permeability values suggest that reservoirs are good enough to store and also permit free flow of fluid. The volume of shale (0.05% to 0.35% analysis reveals that the reservoirs range from shaly sand to slightly shaly sand to clean sand reservoir. On the basis of petrophysics data, the reservoirs are interpreted a good quality reservoir rocks which has been confirmed with high effective porosity range between 20% and high hydrocarbon saturation exceeding 55% water saturation in well 1 and well 2. Water saturation 3 is nearly 100% although the reservoir properties are good.  

  18. 克拉通盆地构造枢纽带类型及其在碳酸盐岩油气成藏中的作用%Types of tectonic hinge zone and its effect on hydrocarbon accumulation in carbonate reservoirs of cratonic basins in China

    Institute of Scientific and Technical Information of China (English)

    汪泽成; 姜华; 刘伟; 谷志东; 王铜山; 江青春

    2012-01-01

    与北美等大型克拉通盆地相比,中国小型克拉通的构造演化更易受周缘构造活动影响.受构造分异的影响,克拉通坳陷盆地存在2大类构造枢纽带,即同沉积期构造枢纽带和跨构造期构造枢纽带.同沉积期构造枢纽带的形成和演化受同沉积断裂活动的影响,控制了碳酸盐台地边缘礁滩体的分布,与相邻的盆地相烃源岩共同构成良好的源-储配置,具备有利的油气成藏条件.跨构造期构造枢纽带主要有3种类型,即“跷跷板”运动枢纽带、克拉通古隆起一前陆隆起叠合枢纽带、多期古隆起继承性叠合枢纽带,发育岩溶型储层和地层-岩性型圈闭,是油气运聚的有利指向区.构造枢纽带是碳酸盐岩油气富集的有利区带,油气勘探前景广阔.%Compared to large cratonic basins in northern America, small cratonic basins in China are more susceptible to peripheral tectonic activities in terms of tectonic evolution. Due to tectonic differentiation, there are commonly two types of tectonic hinge zone in cratonic depression basins, I. E. Synsedimentary tectonic hinge zone and cross-structure tectonic hinge zone. The formation and e-volution of synsedimentary tectonic hinge zones are affected by activity of synsedimentary faults. These controlled distribution of reefs and shoals on carbonate platform margin and formed an excellent source-storage configuration with adjacent source rocks, providing favorable conditions for hydrocarbon accumulation. The cross-structure tectonic hinge zones can be divided into three types, I. E. , "seesaw" movement hinge zone, cratonic palaeouplift-foreland uplift superimposed hinge zone, and multi-phase palaeouplift inheritance superimposed hinge zone. They develop karst reservoirs and stratigraphic-lithologic traps, and are favorable oriented regions of hydrocarbon migration and accumulation. The tectonic hinge zones are favorable for hydrocarbon enrichment in carbonates with broad

  19. Pore structure effect on reservoir electrical properties and well logging evaluation

    Institute of Scientific and Technical Information of China (English)

    Bian Huan-Lin; Guan Ju; Mao Zhi-Qiang; Ju Xiao-Dong; Han Gui-Qing

    2014-01-01

    The reservoir pore structure controls the reservoir quality and resistivity response of hydrocarbon-bearing zones and thus, critically affects logging interpretation. We use petrophysical data in three types of reservoir with different pore structure characteristics to show that the complexity of pore structure had a significant effect on the effective porosity and permeability regardless of geological factors responsible for the formation of pore structure. Moreover,, the distribution and content of conductive fluids in the reservoir varies dramatically owing to pore structure differences, which also induces resistivity variations in reservoir rocks. Hence, the origin of low-resistivity hydrocarbon-bearing zones, except for those with conductive matrix and mud filtrate invasion, is attributed to the complexity of the pore structures. Consequently, reservoir-specific evaluation models, parameters, and criteria should be chosen for resistivity log interpretation to make a reliable evaluation of reservoir quality and fluids.

  20. Architectural Leakage Power Minimization of Scratchpad memories

    Directory of Open Access Journals (Sweden)

    S. Paraneetharan,

    2012-03-01

    Full Text Available Partitioning a memory into multiple blocks that can be independently accessed is a widely used technique to reduce its dynamic power. For embedded systems, its benefits can be even pushed further by properly matching the partition to the memory access patterns. When leakage energy comes into play, however, idle memory blocks must be put into a proper low-leakage sleep state to actually save energy when not accessed. In this case, the matching becomes an instance of the power management problem, because moving to and from this sleep state requires additional energy. An effective solution to the problem of the leakage-aware partitioning of a memory into disjoint sub blocks, in particular, target scratchpad memories, which are commonly used in some embedded systems as a replacement for caches. By this approach, it is able to provide an optimal solution to the leakage-aware partitioning problem.

  1. High charge, low leakage tantalum powders

    Energy Technology Data Exchange (ETDEWEB)

    Schiele, E. K.; Manley Jr., R. V.; Rerat, C. F.

    1985-10-01

    Tantalum powders for electrolytic capacitors having improved electrical capacity and low direct current leakage characteristics are produced by the introduction of combinations of carbon, nitrogen and sulfur-containing materials.

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

    Institute of Scientific and Technical Information of China (English)

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

    2004-01-01

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

  3. Multi-data reservoir history matching for enhanced reservoir forecasting and uncertainty quantification

    KAUST Repository

    Katterbauer, Klemens

    2015-04-01

    Reservoir simulations and history matching are critical for fine-tuning reservoir production strategies, improving understanding of the subsurface formation, and forecasting remaining reserves. Production data have long been incorporated for adjusting reservoir parameters. However, the sparse spatial sampling of this data set has posed a significant challenge for efficiently reducing uncertainty of reservoir parameters. Seismic, electromagnetic, gravity and InSAR techniques have found widespread applications in enhancing exploration for oil and gas and monitoring reservoirs. These data have however been interpreted and analyzed mostly separately, rarely exploiting the synergy effects that could result from combining them. We present a multi-data ensemble Kalman filter-based history matching framework for the simultaneous incorporation of various reservoir data such as seismic, electromagnetics, gravimetry and InSAR for best possible characterization of the reservoir formation. We apply an ensemble-based sensitivity method to evaluate the impact of each observation on the estimated reservoir parameters. Numerical experiments for different test cases demonstrate considerable matching enhancements when integrating all data sets in the history matching process. Results from the sensitivity analysis further suggest that electromagnetic data exhibit the strongest impact on the matching enhancements due to their strong differentiation between water fronts and hydrocarbons in the test cases.

  4. Analysis of ONKALO water leakage mapping results

    Energy Technology Data Exchange (ETDEWEB)

    Ahokas, H.; Nummela, J; Turku, J. [Poeyry Finland Oy, Vantaa (Finland)

    2014-04-15

    As part of the programme for the final disposal of spent nuclear fuel, an analysis has been compiled of water leakage mapping performed in ONKALO. Leakage mapping is part of the Olkiluoto Monitoring Programme (OMO) and the field work has been carried out by Posiva Oy. The main objective of the study is to analyse differences detected between mapping campaigns carried out typically twice a year in 2005-2012. Differences were estimated to be caused by the differences in groundwater conditions caused by seasonal effects or by differences between the years. The effect of technical changes like shotcreting, postgrouting, ventilation etc. on the results was also studied. The development of the visualisation of mapping results was also an objective of this work. Leakage mapping results have been reported yearly in the monitoring reports of Hydrology with some brief comments on the detected differences. In this study, the development of the total area and the number of different leakages as well as the correlation of changes with shotcreting and grouting operations were studied. In addition, traces of fractures on tunnel surfaces, and the location of rock bolts and drain pipes were illustrated together with leakage mapping. In water leakage mapping, the tunnel surfaces are visually mapped to five categories: dry, damp, wet, dripping and flowing. Major changes were detected in the total area of damp leakages. It is likely that the increase has been caused by the condensation of warm ventilation air on the tunnel surfaces and the corresponding decrease by the evaporation of moisture into the dry ventilation air. Shotcreting deep in ONKALO may also have decreased the total area of damp leakages. Changes in the total area and number of wet leakages correlate at least near the surface with differences in yearly precipitation. It is possible that strong rains have also caused a temporary increase in wet leakages. Dripping and wet leakages have been observed on average more

  5. Crude-oil biodegradation via methanogenesis in subsurface petroleum reservoirs.

    Science.gov (United States)

    Jones, D M; Head, I M; Gray, N D; Adams, J J; Rowan, A K; Aitken, C M; Bennett, B; Huang, H; Brown, A; Bowler, B F J; Oldenburg, T; Erdmann, M; Larter, S R

    2008-01-10

    Biodegradation of crude oil in subsurface petroleum reservoirs has adversely affected the majority of the world's oil, making recovery and refining of that oil more costly. The prevalent occurrence of biodegradation in shallow subsurface petroleum reservoirs has been attributed to aerobic bacterial hydrocarbon degradation stimulated by surface recharge of oxygen-bearing meteoric waters. This hypothesis is empirically supported by the likelihood of encountering biodegraded oils at higher levels of degradation in reservoirs near the surface. More recent findings, however, suggest that anaerobic degradation processes dominate subsurface sedimentary environments, despite slow reaction kinetics and uncertainty as to the actual degradation pathways occurring in oil reservoirs. Here we use laboratory experiments in microcosms monitoring the hydrocarbon composition of degraded oils and generated gases, together with the carbon isotopic compositions of gas and oil samples taken at wellheads and a Rayleigh isotope fractionation box model, to elucidate the probable mechanisms of hydrocarbon degradation in reservoirs. We find that crude-oil hydrocarbon degradation under methanogenic conditions in the laboratory mimics the characteristic sequential removal of compound classes seen in reservoir-degraded petroleum. The initial preferential removal of n-alkanes generates close to stoichiometric amounts of methane, principally by hydrogenotrophic methanogenesis. Our data imply a common methanogenic biodegradation mechanism in subsurface degraded oil reservoirs, resulting in consistent patterns of hydrocarbon alteration, and the common association of dry gas with severely degraded oils observed worldwide. Energy recovery from oilfields in the form of methane, based on accelerating natural methanogenic biodegradation, may offer a route to economic production of difficult-to-recover energy from oilfields.

  6. Classification of Complex Reservoirs in Superimposed Basins of Western China

    Institute of Scientific and Technical Information of China (English)

    PANG Xiongqi; ZHOU Xinyuan; LIN Changsong; HUO Zhipeng; LUO Xiaorong; PANG Hong

    2010-01-01

    Many of the sedimentary basins in western China were formed through the superposition and compounding of at least two previously developed sedimentary basins and in general they can be termed as complex superimposed basins.The distinct differences between these basins and monotype basins are their discontinuous stratigraphic sedimentation,stratigraphic structure and stratigraphic stress-strain action over geological history.Based on the correlation of chronological age on structural sections,superimposed basins can be divided into five types in this study:(1)continuous sedimentation type superimposed basins,(2)middle and late stratigraphic superimposed basins,(3)early and late stratigraphic superimposed basins,(4)early and middle stratigraphic superimposed basins,and(5)long-term exposed superimposed basins.Multiple source-reservoir-caprock assemblages have developed in such basins.In addition,multi-stage hydrocarbon generation and expulsion,multiple sources,polycyclic hydrocarbon accumulation and multiple-type hydrocarbon reservoirs adjustment,reformation and destruction have occurred in these basins.The complex reservoirs that have been discovered widely in the superimposed basins to date have remarkably different geologic features from primary reservoirs,and the root causes of this are folding,denudation and the fracture effect caused by multiphase tectonic events in the superimposed basins as well as associated seepage,diffusion,spilling,oxidation,degradation and cracking.Based on their genesis characteristics,complex reservoirs are divided into five categories:(1)primary reservoirs,(2)trap adjustment type reservoirs,(3)component variant reservoirs,(4)phase conversion type reservoirs and(5)scale-reformed reservoirs.

  7. The Effects of Subsurface Heterogeneity on Detectability of CO2 Leakage to Shallow Groundwater Aquifers

    Science.gov (United States)

    Wolaver, B. D.; Sun, A. Y.; Nicot, J.; Hovorka, S. D.; Nuñez-Lopez, V.; Young, M.

    2011-12-01

    Numerical simulations of CO2 storage reservoir leakage can be used to assess risks of shallow groundwater aquifer contamination during monitoring network design. Improperly plugged and abandoned wells are well known to represent one of the greatest risks to successful containment at geologic carbon sequestration sites. Casing and cement seal failure of wells penetrating the confining layer may create fast-flow pathways for CO2 and brine migration from the storage reservoir into the shallow subsurface. To protect drinking water aquifers from possible leaks, injection permits require identification of artificial penetrations and evaluation that wells are adequately plugged and abandoned. However, assumptions made during well evaluation may overlook the likelihood of well failure leading to a leak into an aquifer. We present a monitoring approach that provides quick and accurate detection in the event of a leak to an aquifer. Sand and shale facies are classified to simulate aquifer heterogeneity using representative borehole geophysical data from Texas, U.S.A. Gulf Coast Aquifer System wells. Numerical models simulate pressure perturbations in response to a leak to an aquifer overlying a storage reservoir. Candidate monitoring well locations for a possible leak of randomly selected location are chosen from a suite of possible wells based on the detectability of CO2 leakage from the groundwater model. We first show that the locations and magnitudes of leakage can be identified for homogeneous aquifers by using an inversion procedure and pressure observations. We then consider the effects of conceptual model uncertainty, pressure measurement error, and background noise on detectability of leaky wells. While substantial previous work quantified pressure perturbations caused by leaky wells using analytical solutions or simple numerical model configurations, the effects of formation heterogeneity on pressure perturbation and other uncertain factors are not well examined

  8. A harmonic pulse testing method for leakage detection in deep subsurface storage formations

    Science.gov (United States)

    Sun, Alexander Y.; Lu, Jiemin; Hovorka, Susan

    2015-06-01

    Detection of leakage in deep geologic storage formations (e.g., carbon sequestration sites) is a challenging problem. This study investigates an easy-to-implement frequency domain leakage detection technology based on harmonic pulse testing (HPT). Unlike conventional constant-rate pressure interference tests, HPT stimulates a reservoir using periodic injection rates. The fundamental principle underlying HPT-based leakage detection is that leakage modifies a storage system's frequency response function, thus providing clues of system malfunction. During operations, routine HPTs can be conducted at multiple pulsing frequencies to obtain experimental frequency response functions, using which the possible time-lapse changes are examined. In this work, a set of analytical frequency response solutions is derived for predicting system responses with and without leaks for single-phase flow systems. Sensitivity studies show that HPT can effectively reveal the presence of leaks. A search procedure is then prescribed for locating the actual leaks using amplitude and phase information obtained from HPT, and the resulting optimization problem is solved using the genetic algorithm. For multiphase flows, the applicability of HPT-based leakage detection procedure is exemplified numerically using a carbon sequestration problem. Results show that the detection procedure is applicable if the average reservoir conditions in the testing zone stay relatively constant during the tests, which is a working assumption under many other interpretation methods for pressure interference tests. HPT is a cost-effective tool that only requires periodic modification of the nominal injection rate. Thus it can be incorporated into existing monitoring plans with little additional investment.

  9. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  10. Main Controls on Hydrocarbon Accumulation in the Paleozoic in Central Saudi Arabia

    Institute of Scientific and Technical Information of China (English)

    Bai Guoping

    2007-01-01

    Saudi Arabia is renown for its rich oil and gas resources with the bulk of the reserves reservoired in the Mesozoic.However,the discovery of Paleozoic fields in the late 1980s has encouraged further exploration in the Paleozoic.This paper reviews the salient features of the Paleozoic petroleum geology in central Saudi Arabia and discusses the main factors controlling hydrocarbon accumulation in the Paleozoic.The Lower Silurian Qusaiba hot shale is the principal source rock for the hydrocarbons discovered in the Ordovician to Permian reservoirs.Of them,the Permo-Carboniferous Unayzah and Upper Ordovician Sarah Formations have the best exploration potential.The key factors controlling hydrocarbon accumulation in the Unayzah Formation are migration pathways and reservoir petrophysics.The key factors controlling hydrocarbon accumulation in the Sarah Formation are reservoir petrophysics and the development of structural traps.

  11. Multi Data Reservoir History Matching using the Ensemble Kalman Filter

    KAUST Repository

    Katterbauer, Klemens

    2015-05-01

    Reservoir history matching is becoming increasingly important with the growing demand for higher quality formation characterization and forecasting and the increased complexity and expenses for modern hydrocarbon exploration projects. History matching has long been dominated by adjusting reservoir parameters based solely on well data whose spatial sparse sampling has been a challenge for characterizing the flow properties in areas away from the wells. Geophysical data are widely collected nowadays for reservoir monitoring purposes, but has not yet been fully integrated into history matching and forecasting fluid flow. In this thesis, I present a pioneering approach towards incorporating different time-lapse geophysical data together for enhancing reservoir history matching and uncertainty quantification. The thesis provides several approaches to efficiently integrate multiple geophysical data, analyze the sensitivity of the history matches to observation noise, and examine the framework’s performance in several settings, such as the Norne field in Norway. The results demonstrate the significant improvements in reservoir forecasting and characterization and the synergy effects encountered between the different geophysical data. In particular, the joint use of electromagnetic and seismic data improves the accuracy of forecasting fluid properties, and the usage of electromagnetic data has led to considerably better estimates of hydrocarbon fluid components. For volatile oil and gas reservoirs the joint integration of gravimetric and InSAR data has shown to be beneficial in detecting the influx of water and thereby improving the recovery rate. Summarizing, this thesis makes an important contribution towards integrated reservoir management and multiphysics integration for reservoir history matching.

  12. HYDROCARBONS RESERVES IN VENEZUELA

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Cruz, D.J.

    2007-07-01

    Venezuela is an important player in the energy world, because of its hydrocarbons reserves. The process for calculating oil and associated gas reserves is described bearing in mind that 90% of the gas reserves of Venezuela are associated to oil. Likewise, an analysis is made of the oil reserves figures from 1975 to 2003. Reference is also made to inconsistencies found by international experts and the explanations offered in this respect by the Ministry of Energy and Petroleum (MENPET) and Petroleos de Venezuela (PDVSA) regarding the changes that took place in the 1980s. In turn, Hubbert's Law is explained to determine peak production of conventional oil that a reservoir or field will reach, as well as its relationship with remaining reserves. Emphasis is placed on the interest of the United Nations on this topic. The reserves of associated gas are presented along with their relationship with the different crude oils that are produced and with injected gas, as well as with respect to the possible changes that would take place in the latter if oil reserves are revised. Some recommendations are submitted so that the MENPET starts preparing the pertinent policies ruling reserves. (auth)

  13. Reservoir Engineering Studies of Geopressured Geothermal Energy Resource

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kun Sang [Kyonggi University, Suwon (Korea)

    1998-04-30

    Transient pressure analysis techniques were used to evaluate the performance of the Gladys McCall geopressured-geothermal reservoir which has been monitored and tested under U.S. Department of Energy geopressured -geothermal research program. Analysis of transient pressure data furnished a reservoir description such as the formation parameters, pore volume and shape of the reservoir, and average reservoir pressure. Results of pressure tests suggest that the Gladys McCall reservoir probably has a long narrow shape with the well located off-center. During both production and shut-in periods, pressure buildup tests indicated some degree of external pressure support. Aquifer recharging was believed to be the main source. An aquifer influx model was derived from a conceptual model of water leakage through a partially sealing fault into the reservoir under steady-state conditions. Moreover, a match of the pressure history required that the conductivity of the fault be a function of the pressure difference between the supporting aquifer and the reservoir. Results of analyses provided a quantitative evaluation of the reservoir and a better understanding of the reservoir energy drive mechanism. (author). 14 refs., 1 tab., 4 figs.

  14. Raman characteristics of hydrocarbon and hydrocarbon inclusions

    Institute of Scientific and Technical Information of China (English)

    ZHANG Nai; TIAN ZuoJi; LENG YingYing; WANG HuiTong; SONG FuQing; MENG JianHua

    2007-01-01

    The Raman spectrograms of hydrocarbon standard samples show that: (1) the Raman spectrogram of normal paraffin has very strong peaks of methyl and methylene (from 2700 cm-1 to 2970 cm-1); (2)branch methyl has the particular peak of 748 cm-1±; (3) six cyclic has the particular peak of 804 cm-1±; (4)phenyl has two particular peaks of 988 cm-1± and 3058 cm-1± and the 988 cm-1± peak is stronger than the 3058 cm-1± peak; and (5) hexene has three alkenyl spectrum peaks of 1294 cm-1±, 1635 cm-1± and 2996 cm-1±, with the 1635 cm-1± peak being the strongest, showing that the number of carbon in hydrocarbon does not affect its Raman spectrogram, and the hydrocarbon molecular structure and base groups affect its Raman spectrogram, the same hydrocarbons (such as normal paraffin) have the same Raman spectrogram; the types (such as CH4, C2H6, C3H8) and the content of hydrocarbon in oil inclusions are not estimated by their characteristic Raman peaks. According to the Raman spectrograms of hydrocarbon compositions, the Raman spectrogram of hydrocarbon inclusion can be divided into five types: saturated hydrocarbon Raman spectrogram, fluoresce Raman spectrogram, saturated hydrocarbon bitumen Raman spectrogram, bitumen Raman spectrogram, and ethane Raman spectrogram.And according to the characteristics of Raman spectrogram, hydrocarbon inclusions can be divided into five types: saturated hydrocarbon inclusion, less saturated hydrocarbon (oil or gas) inclusion,saturated hydrocarbon bitumen inclusion, bitumen inclusion, and methane water inclusion.

  15. Raman characteristics of hydrocarbon and hydrocarbon inclusions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Raman spectrograms of hydrocarbon standard samples show that: (1) the Raman spectrogram of normal paraffin has very strong peaks of methyl and methylene (from 2700 cm-1 to 2970 cm-1); (2) branch methyl has the particular peak of 748 cm-1±; (3) six cyclic has the particular peak of 804 cm-1±; (4) phenyl has two particular peaks of 988 cm-1± and 3058 cm-1± and the 988 cm-1± peak is stronger than the 3058 cm-1± peak; and (5) hexene has three alkenyl spectrum peaks of 1294 cm-1±, 1635 cm-1± and 2996 cm-1±, with the 1635 cm-1± peak being the strongest, showing that the number of carbon in hy-drocarbon does not affect its Raman spectrogram, and the hydrocarbon molecular structure and base groups affect its Raman spectrogram, the same hydrocarbons (such as normal paraffin) have the same Raman spectrogram; the types (such as CH4, C2H6, C3H8) and the content of hydrocarbon in oil inclu-sions are not estimated by their characteristic Raman peaks. According to the Raman spectrograms of hydrocarbon compositions, the Raman spectrogram of hydrocarbon inclusion can be divided into five types: saturated hydrocarbon Raman spectrogram, fluoresce Raman spectrogram, saturated hydro-carbon bitumen Raman spectrogram, bitumen Raman spectrogram, and ethane Raman spectrogram. And according to the characteristics of Raman spectrogram, hydrocarbon inclusions can be divided into five types: saturated hydrocarbon inclusion, less saturated hydrocarbon (oil or gas) inclusion, saturated hydrocarbon bitumen inclusion, bitumen inclusion, and methane water inclusion.

  16. Oil and reservoir core extracts compositional variations in the Kerkennah Ouest fields, Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Ghenma, R. [ETAP, Belvedere (Tunisia); LaFargue, E. [IFP, Malmaison (France)

    1995-08-01

    A suite of oils and reservoir core extracts from the Kerkennah oil fields in Tunisia has been analyzed by various geochemical techniques to elucidate the geological processes which cause variations in oil and extracts composition and their resulting fingerprinting in the different reservoirs of the field. The results obtained greatly helped in the understanding of filling directions which is valuable for future exploration of satellite fields. The oil pools studied are parts of a large geologic province ({open_quotes}the pelagienne plateforme{close_quotes}) where the main oil fields are limited by NW-SE major faults. The two main reservoirs we encountered in the carbonate series of Turonian and Eocene ages and the best reservoir qualities are found in the packstone and grainstone Nummulites facies. Numerous fractures we observed through the fields and we could demonstrate their influence on the filling history of the different fields as well as on the present oil production. Detailed analysis of the light hydrocarbons (C{sub 20-}) as well as the complete study of the C{sub 15+} hydrocarbons indicate compositional variations between the hydrocarbons stored in the Eocene and Turonian reservoirs. The core extracts from the two reservoirs also shows some variations with in particular maturity differences. Apparently the only possible source rock in the area is represented by the Bahloul formation of Turonian age. Within this scenario, we proposed the hypothesis of different behaviours of the main faults over geological time: a first period where the faults acted as conduits for hydrocarbon migration towards both Turonian and Eocene reservoirs and a second period where the faults became impervious to the hydrocarbons moving towards the Eocene reservoirs thus resulting in the storage of more mature hydrocarbons in the Turonian reservoirs only. Also of interest is the observation of different levels of homogenization in the Turonian reservoirs from one field to another.

  17. Detection of carbon dioxide leakage during injection in deep saline formations by pressure tomography

    Science.gov (United States)

    Hu, Linwei; Bayer, Peter; Brauchler, Ralf

    2016-07-01

    CO2 injected into storage formations may escape to the overlying permeable layers. Mixed-phase diffusivity, namely the ratio of hydraulic conductivity and specific storage of the phase mixture, declines with increasing CO2 saturation. Thus, it can be an indicator of CO2 leakage. In this study, we perform interference brine or CO2 injection tests in a synthetic model, including a storage reservoir, an above aquifer, and a caprock. Pressure transients derived from an observation well are utilized for a travel-time based inversion technique. Variations of diffusivity are resolved by inverting early travel time diagnostics, providing an insight of plume development. Results demonstrate that the evolution of CO2 leakage in the above aquifer can be inferred by interpreting and comparing the pressure observations, travel times, and diffusivity tomograms from different times. The extent of the plume in reservoir and upper aquifer are reconstructed by clustering the time-lapse data sets of the mixed-phase diffusivity, as the diffusivity cannot be exactly reproduced by the inversion. Furthermore, this approach can be used to address different leaky cases, especially for leakage occurring during the injection.

  18. Geochemical Implications of CO2 Leakage Associated with Geologic Storage: A Review

    Energy Technology Data Exchange (ETDEWEB)

    Harvey, Omar R.; Qafoku, Nikolla; Cantrell, Kirk J.; Brown, Christopher F.

    2012-07-09

    Leakage from deep storage reservoirs is a major risk factor associated with geologic sequestration of carbon dioxide (CO2). Different scientific theories exist concerning the potential implications of such leakage for near-surface environments. The authors of this report reviewed the current literature on how CO2 leakage (from storage reservoirs) would likely impact the geochemistry of near surface environments such as potable water aquifers and the vadose zone. Experimental and modeling studies highlighted the potential for both beneficial (e.g., CO2 re sequestration or contaminant immobilization) and deleterious (e.g., contaminant mobilization) consequences of CO2 intrusion in these systems. Current knowledge gaps, including the role of CO2-induced changes in redox conditions, the influence of CO2 influx rate, gas composition, organic matter content and microorganisms are discussed in terms of their potential influence on pertinent geochemical processes and the potential for beneficial or deleterious outcomes. Geochemical modeling was used to systematically highlight why closing these knowledge gaps are pivotal. A framework for studying and assessing consequences associated with each factor is also presented in Section 5.6.

  19. Determination of leakage areas in nuclear piping

    Energy Technology Data Exchange (ETDEWEB)

    Keim, E. [Siemens/KWU, Erlangen (Germany)

    1997-04-01

    For the design and operation of nuclear power plants the Leak-Before-Break (LBB) behavior of a piping component has to be shown. This means that the length of a crack resulting in a leak is smaller than the critical crack length and that the leak is safely detectable by a suitable monitoring system. The LBB-concept of Siemens/KWU is based on computer codes for the evaluation of critical crack lengths, crack openings, leakage areas and leakage rates, developed by Siemens/KWU. In the experience with the leak rate program is described while this paper deals with the computation of crack openings and leakage areas of longitudinal and circumferential cracks by means of fracture mechanics. The leakage areas are determined by the integration of the crack openings along the crack front, considering plasticity and geometrical effects. They are evaluated with respect to minimum values for the design of leak detection systems, and maximum values for controlling jet and reaction forces. By means of fracture mechanics LBB for subcritical cracks has to be shown and the calculation of leakage areas is the basis for quantitatively determining the discharge rate of leaking subcritical through-wall cracks. The analytical approach and its validation will be presented for two examples of complex structures. The first one is a pipe branch containing a circumferential crack and the second one is a pipe bend with a longitudinal crack.

  20. Reservoir characteristics and genesis of high-porosity and high-permeability reservoirs in Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Based on detailed studies, this paper proposes that in the Tarim Basin, hydrocarbon reservoirs widespread either in vertical sequences or in plane and high-porosity and high-permeability reservoirs are developed all over the basin. However, obvious difference and heterogeneity exist among different kinds of reservoirs. The lithologic characteristics, reservoir space types and reservoir properties in various strata have been probed. The result indicates that although the Paleozoic carbonates have been deeply buried for a long period, high-quality reservoirs with the porosity of up to 5%-8% (12% as the maximum) and the permeability of 10×10?3-100×10?3 ?m2 (1000×10?3 ?m2 as the maximum) can be found in certain areas. These include the area with the development of reefs and carbonate beaches, the weathered-crust buried-hill belts that have undergone the long-term exposure, weathering and leaching, the area with the development of dolomitization, and those areas that have experienced the resolution of carbonic acid and organic acid generated by the maturity of the organic matter. Finally, the genesis of the high-porosity and high-permeability reservoirs in deep-buried conditions (with the depth more than 3500 m) have been investigated thoroughly.

  1. Analysis of Leakages and Leakage Reduction Methods in UDSM CMOS VLSI Circuits.

    Directory of Open Access Journals (Sweden)

    Sagar Ekade

    2014-04-01

    Full Text Available This is the era of portable devices which need to be powered by battery. Due to scarcity of space and leakages in chips, battery life is a serious concern. As technology advances, scaling of transistor feature size and supply voltage has improved the performance, increased the transistor density and reduced the power required by the chip. The maximum power consumed by the chip is the function of its technology along with its implementation. As technology is scaling down and CMOS circuits are supplied with lower supply voltages, the static power i.e. standby leakage current becomes very crucial. In Ultra Deep-submicron regime scaling has reduced the threshold voltage and that has led to increase in leakage current in sub-threshold region and hence rise in static power dissipation. This paper presents a critical analysis of leakages and leakage reduction techniques.

  2. Risk factors of pancreatic leakage after pancreaticoduodenectomy

    Institute of Scientific and Technical Information of China (English)

    Yin-Mo Yang; Xiao-Dong Tian; Yan Zhuang; Wei-Min Wang; Yuan-Lian Wan; Yan-Ting Huang

    2005-01-01

    AIM: To analyze the risk factors for pancreatic leakage after pancreaticoduodenectomy (PD) and to evaluate whether duct-to-mucosa pancreaticojejunostomy could reduce the risk of pancreatic leakage.METHODS: Sixty-two patients who underwent PD at our hospital between January 2000 and November 2003 were reviewed retrospectively. The primary diseases of the patients included pancreas cancer, ampullary cancer, bile duct cancer, islet cell cancer, duodenal cancer, chronic pancreatitis, pancreatic cystadenoma, and gastric cancer.Standard PD was performed for 25 cases, PD with extended lymphadenectomy for 27 cases, pylorus-preserving PD for 10 cases. A duct-to-mucosa pancreaticojejunostomy was performed for patients with a hard pancreas and a dilated pancreatic duct, and a traditional end-to-end invagination pancreaticojejunostomy for patients with a soft pancreas and a non-dilated duct. Patients were divided into two groups according to the incidence of postoperative pancreaticojejunal anastomotic leakage: 10 cases with leakage and 52 cases without leakage. Seven preoperative and six intraoperative risk factors with the potential to affect the incidence of pancreatic leakage were analyzed with SPSS10.0 software. Logistic regression was then used to determine the effect of multiple factors on pancreatic leakage.RESULTS: Of the 62 patients, 10 (16.13%) were identified as having pancreatic leakage after operation. Other major postoperative complications included delayed gastric emptying (eight patients), abdominal bleeding (four patients), abdominal abscess (three patients) and wound infection (two patients). The overall surgical morbidity was 43.5% (27/62). The hospital mortality in this series was 4.84% (3/62), and the mortality associated with pancreatic fistula was 10% (1/10). Sixteen cases underwent duct-to-mucosa pancreaticojejunostomy and 1 case (1/16, 6.25%) devel-oped postoperative pancreatic leakage, 46 cases underwent invagination pancreaticojejunostomy and 9

  3. A study of hydrocarbons associated with brines from DOE geopressured wells. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Keeley, D.F.

    1993-07-01

    Accomplishments are summarized on the following tasks: distribution coefficients and solubilities, DOE design well sampling, analysis of well samples, review of theoretical models of geopressured reservoir hydrocarbons, monitor for aliphatic hydrocarbons, development of a ph meter probe, DOE design well scrubber analysis, removal and disposition of gas scrubber equipment at Pleasant Bayou Well, and disposition of archived brines.

  4. A study of hydrocarbons associated with brines from DOE geopressured wells

    Energy Technology Data Exchange (ETDEWEB)

    Keeley, D.F.

    1993-01-01

    Accomplishments are summarized on the following tasks: distribution coefficients and solubilities, DOE design well sampling, analysis of well samples, review of theoretical models of geopressured reservoir hydrocarbons, monitor for aliphatic hydrocarbons, development of a ph meter probe, DOE design well scrubber analysis, removal and disposition of gas scrubber equipment at Pleasant Bayou Well, and disposition of archived brines.

  5. Air leakage in residential solar heating systems

    Science.gov (United States)

    Shingleton, J. G.; Cassel, D. E.; Overton, R. L.

    1981-02-01

    A series of computer simulations was performed to evaluate the effects of component air leakage on system thermal performance for a typical residential solar heating system, located in Madison, Wisconsin. Auxiliary energy required to supplement solar energy for space heating was determined using the TRNSYS computer program, for a range of air leakage rates at the solar collector and pebble bed storage unit. The effects of heat transfer and mass transfer between the solar equipment room and the heated building were investigated. The effect of reduced air infiltration into the building due to pressurized by the solar air heating system were determined. A simple method of estimating the effect of collector array air leakage on system thermal performance was evaluated, using the f CHART method.

  6. Leakage current measurement in transformerless PV inverters

    DEFF Research Database (Denmark)

    Kerekes, Tamas; Sera, Dezso; Mathe, Laszlo

    2012-01-01

    to be used in commercial PV inverters for the measurement of leakage and fault ground currents. The German VDE0126–1–1 standard gives the limit for fault and leakage ground currents and all grid connected PV inverters have to comply with these limits and disconnect from the grid in case of a fault.......Photovoltaic (PV) installations have seen a huge increase during the last couple of years. Transformerless PV inverters are gaining more share of the total inverter market, due to their high conversion efficiency, small weight and size. Nevertheless safety should have an important role in case...... of these tranformerless systems, due to the missing galvanic isolation. Leakage and fault current measurement is a key issue for these inverter topologies to be able to comply with the required safety standards. This article presents the test results of two different current measurement sensors that were suggested...

  7. Survey on Techniques for Detecting Data Leakage

    Directory of Open Access Journals (Sweden)

    Bhosale Pranjali A

    2016-06-01

    Full Text Available In current business scenario, critical data is to be shared and transferred by organizations to many stake holders in order to complete particular task. The critical data include intellectual copyright, patient information etc. The activities like sharing and transferring of such critical data includes threats like leakage of information, misuse of data, illegal access to data and/or alteration of data. It is necessary to deal with such problem efficiently and effectively, popular solutions to this problem are use of firewalls, data loss prevention tools and watermarking. But sometimes culprit succeeds in overcoming such security measures hence, if organizations becomes able to find out the guilty client responsible for leakage of particular data then risk of data leakage is reduced. For this many systems are proposed, this paper includes information about techniques discussed in some of such methodologies.

  8. Non-parametric Bayesian networks for parameter estimation in reservoir engineering

    NARCIS (Netherlands)

    Zilko, A.A.; Hanea, A.M.; Hanea, R.G.

    2013-01-01

    The ultimate goal in reservoir engineering is to optimize hydrocarbon recovery from a reservoir. To achieve the goal, good knowledge of the subsurface properties is crucial. One of these properties is the permeability. Ensemble Kalman Filter (EnKF) is the most common tool used to deal with this

  9. Feasibility of Gas Drive in Fang-48 Fault Block Oil Reservoir

    Institute of Scientific and Technical Information of China (English)

    Cui Lining; Hou Jirui; Yin Xiangwen

    2007-01-01

    The Fang-48 fault block oil reservoir is an extremely low permeability reservoir, and it is difficult to produce such a reservoir by waterflooding. Laboratory analysis of reservoir oil shows that the minimum miscibility pressure for CO2 drive in Fang-48 fault block oil reservoir is 29 MPa, lower than the formation fracture pressure of 34 MPa, so the displacement mechanism is miscible drive. The threshold pressure gradient for gas injection is less than that for waterflooding, and the recovery by gas drive is higher than waterflooding. Furthermore, the threshold pressure gradient for carbon dioxide injection is smaller than that for hydrocarbon gas, and the oil recovery by carbon dioxide drive is higher than that by hydrocarbon gas displacement, so carbon dioxide drive is recommended for the development of the Fang-48 fault block oil reservoir.

  10. Inward Leakage in Tight-Fitting PAPRs

    Directory of Open Access Journals (Sweden)

    Frank C. Koh

    2011-01-01

    Full Text Available A combination of local flow measurement techniques and fog flow visualization was used to determine the inward leakage for two tight-fitting powered air-purifying respirators (PAPRs, the 3M Breathe-Easy PAPR and the SE 400 breathing demand PAPR. The PAPRs were mounted on a breathing machine head form, and flows were measured from the blower and into the breathing machine. Both respirators leaked a little at the beginning of inhalation, probably through their exhalation valves. In both cases, the leakage was not enough for fog to appear at the mouth of the head form.

  11. Quantifying information leakage of randomized protocols

    DEFF Research Database (Denmark)

    Biondi, Fabrizio; Legay, Axel; Malacaria, Pasquale;

    2015-01-01

    capable to observe the internal behavior of the system, and quantify the information leakage of such systems. We also use our method to obtain an algorithm for the computation of channel capacity from our Markovian models. Finally, we show how to use the method to analyze timed and non-timed attacks......The quantification of information leakage provides a quantitative evaluation of the security of a system. We propose the usage of Markovian processes to model deterministic and probabilistic systems. By using a methodology generalizing the lattice of information approach we model refined attackers...

  12. Quantifying information leakage of randomized protocols

    DEFF Research Database (Denmark)

    Biondi, Fabrizio; Legay, Axel; Malacaria, Pasquale

    2015-01-01

    The quantification of information leakage provides a quantitative evaluation of the security of a system. We propose the usage of Markovian processes to model deterministic and probabilistic systems. By using a methodology generalizing the lattice of information approach we model refined attackers...... capable to observe the internal behavior of the system, and quantify the information leakage of such systems. We also use our method to obtain an algorithm for the computation of channel capacity from our Markovian models. Finally, we show how to use the method to analyze timed and non-timed attacks...

  13. Effects of hydrocarbon physical properties on caprock’s capillary sealing ability

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    A new mechanics formula of caprock’s capillary sealing ability has been established in this paper, in which the boundary layer resistance was considered and characterized by starting pressure gradient. The formula shows that capillary sealing ability of caprock is determined not only by the capillary force of rock and the buoyancy of hydrocarbon column, but also by the starting pressure gradient of hydrocarbons and the thickness of caprock. The buoyancy of hydrocarbon column, the starting pressure gradient of hydrocarbon, and the capillary force of caprock are affected by hydrocarbon density, hydrocarbon viscosity, and hydrocarbon-water interface tension respectively. Based on hydrocarbon property data of reservoirs of Jiyang Depression and equations from literature, the effects of hydrocarbon density, hydrocarbon viscosity, and hydrocarbon-water interface tension on the sealing ability of caprock are analyzed. Under formational conditions, the sealing ability of oil caprock can vary up to dozens times because of the variations of the oil density, oil viscosity, and oil-water interface tension. Thus, the physical characters of hydrocarbon should be considered when evaluating the capillary sealing ability of caprocks. Study of the effects of physical characters on sealing ability of caprock can provide guidance to exploring special physical property hydrocarbon resources, such as viscous oils, and hydrocarbon resources in special pressure-temperature environments.

  14. Reservoir geochemistry. A reservoir engineering perspective

    Energy Technology Data Exchange (ETDEWEB)

    England, W.A. [BP Exploration, Chertsey Road, Sunbury-on-Thames, Middlesex, TW16 7LN (United Kingdom)

    2007-09-15

    This paper reviews the applications of reservoir geochemistry from a reservoir engineering point of view. Some of the main tasks of reservoir engineering are discussed with an emphasis on the importance of appraising reservoirs in the pre-development stage. A brief review of the principal methods and applications of reservoir geochemistry are given, in the context of applications to reservoir engineering problems. The importance of compositional differences in fluid samples from different depths or spatial locations is discussed in connection with the identification of internal flow barriers. The importance of understanding the magnitude and origin of vertical compositional gradients is emphasised because of possible confusion with purely lateral changes. The geochemical origin and rate of dissipation of compositional differences over geological time is discussed. Geochemical techniques suitable for bulk petroleum fluid samples include GC fingerprinting, GCMS, isotopic and PVT measurements. Core sample petroleum extracts may also be studied by standard geochemical methods but with the added complication of possible contamination by drilling mud. Aqueous phase residual salt extracts can be studied by strontium isotope analysis from core samples. Petroleum fluid inclusions allow the possibility of establishing the composition of paleo-accumulations. The problems in predicting flow barriers from geochemical measurements are discussed in terms of 'false positives' and 'false negatives'. Suggestions are made for areas that need further development in order to encourage the wider acceptance and application of reservoir geochemistry by the reservoir engineering community. The importance of integrating all available data is emphasised. Reservoir geochemistry may be applied to a range of practical engineering problems including production allocation, reservoir compartmentalisation, and the prediction of gravitational gradients. In this review

  15. Petroleum geochemical proxies for reservoir engineering parameters

    Energy Technology Data Exchange (ETDEWEB)

    Bennett, B. [Petroleum Reservoir Group (PRG), Department of Geology and Geophysics, University of Calgary, 2500 University Drive NW, Calgary, Alberta (Canada); Lager, A. [NRG: School of Civil Engineering and Geosciences, Drummond Building, The University, Newcastle upon Tyne, NE1 7RU (United Kingdom); Potter, D.K.; Buckman, J.O. [Institute of Petroleum Engineering, Heriot-Watt University, Riccarton, Edinburgh, EH14 4AS (United Kingdom); Larter, S.R. [Petroleum Reservoir Group (PRG), Department of Geology and Geophysics, University of Calgary, 2500 University Drive NW, Calgary, Alberta (Canada); NRG: School of Civil Engineering and Geosciences, Drummond Building, The University, Newcastle upon Tyne, NE1 7RU (United Kingdom)

    2007-09-15

    The prediction of fluid flow behaviour in petroleum reservoirs is influenced by the physical and chemical processes active in interacting crude oil/brine/rock systems. It is usually not possible to assess these complex systems directly so proxies for molecular scale behaviour are needed. By their very nature, polar non-hydrocarbons are sensitive to fluid-rock interactions, and if properly exploited they may be utilised as proxies for describing reservoir engineering properties (e.g. wettability) that are also sensitive to fluid-rock interactions. We have identified a group of aromatic oxygen (alkylphenols and alkylfluorenones) and aromatic nitrogen (alkylcarbazoles) compounds present in petroleum that appear to respond to variations in fluid-rock properties. Here we describe the chemical and physical changes in a series of core samples obtained from North Sea reservoirs. A number of petrophysical parameters displayed strong correlations with polar non-hydrocarbon occurrence. For example, deflections in gamma ray logs in response to clay content in a coarsening upwards sandstone unit also showed similar deflections from a number of geochemical logs. A core-flood experiment was designed to monitor the chemical and physical changes during oil migration in a siltstone core. Following completion of the core-flood experiment, Environmental Scanning Electron Microscopy (ESEM) analysis of core samples indicated hydrophilic and hydrophobic surface tendencies grading throughout the core. The distributions of polar non-hydrocarbons (e.g. C{sub 0}-C{sub 3}-phenols) appear to correspond closely to the observed wettability alteration. The results confirm the potential for developing proxies for fluid-rock interactions through monitoring the surface active compounds present in the polar non-hydrocarbon fraction of petroleum. (author)

  16. Noise-Produced Patterns in Images Constructed from Magnetic Flux Leakage Data

    CERN Document Server

    Pimenova, Anastasiya V; Levesley, Jeremy; Elkington, Peter; Bacciarelli, Mark

    2015-01-01

    Magnetic flux leakage measurements help identify the position, size and shape of corrosion-related defects in steel casings used to protect boreholes drilled into oil and gas reservoirs. Images constructed from magnetic flux leakage data contain patterns related to noise inherent in the method. We investigate the patterns and their scaling properties for the case of delta-correlated input noise, and consider the implications for the method's ability to resolve defects. The analytical evaluation of the noise-produced patterns is made possible by model reduction facilitated by large-scale approximation. With appropriate modification, the approach can be employed to analyze noise-produced patterns in other situations where the data of interest are not measured directly, but are related to the measured data by a complex linear transform involving integrations with respect to spatial coordinates.

  17. Watertightness of chiew larn reservoir, suratthani, Southern Thailand

    Science.gov (United States)

    Chittrakarn, P.

    Chiew Larn reservoir is formed by damming the Khlong Saeng valley which is located in Suratthani, Southern Thailand. The maximum water level and the limestone perviousness are the main problems of this project. At the southern reservoir rim, there is a limestone area that runs from Khlong Saeng to the Khlong Sok valley giving rise to concern about reservoir leakage. To cope with this problem, the hydrogeology of this basin was studied in order to confirm that the underground water table is higher than the reservoir level. Hydrogeological observations, such as the water inventory of the surface creeks and ponds, flourescence test of the underground water including underground water measurement in rotary drill-holes, demonstrated that the underground water table in this area is high enough to prevent the leakage of reservoir water. This conclusion is supported by the high water level recorded in DH-1, at the ground elevation of 176 mMSL, depth 80 m showing that the elevation of the ground water table is at 173 mMSL in April 1973, at the end of the dry season.

  18. Large reservoirs: Chapter 17

    Science.gov (United States)

    Miranda, Leandro E.; Bettoli, Phillip William

    2010-01-01

    Large impoundments, defined as those with surface area of 200 ha or greater, are relatively new aquatic ecosystems in the global landscape. They represent important economic and environmental resources that provide benefits such as flood control, hydropower generation, navigation, water supply, commercial and recreational fisheries, and various other recreational and esthetic values. Construction of large impoundments was initially driven by economic needs, and ecological consequences received little consideration. However, in recent decades environmental issues have come to the forefront. In the closing decades of the 20th century societal values began to shift, especially in the developed world. Society is no longer willing to accept environmental damage as an inevitable consequence of human development, and it is now recognized that continued environmental degradation is unsustainable. Consequently, construction of large reservoirs has virtually stopped in North America. Nevertheless, in other parts of the world construction of large reservoirs continues. The emergence of systematic reservoir management in the early 20th century was guided by concepts developed for natural lakes (Miranda 1996). However, we now recognize that reservoirs are different and that reservoirs are not independent aquatic systems inasmuch as they are connected to upstream rivers and streams, the downstream river, other reservoirs in the basin, and the watershed. Reservoir systems exhibit longitudinal patterns both within and among reservoirs. Reservoirs are typically arranged sequentially as elements of an interacting network, filter water collected throughout their watersheds, and form a mosaic of predictable patterns. Traditional approaches to fisheries management such as stocking, regulating harvest, and in-lake habitat management do not always produce desired effects in reservoirs. As a result, managers may expend resources with little benefit to either fish or fishing. Some locally

  19. Adsorption of polar aromatic hydrocarbons on synthetic calcite

    DEFF Research Database (Denmark)

    Madsen, Lene; Grahl-Madsen, Laila; Grøn, Christian

    1996-01-01

    The wettability of hydrocarbon reservoirs depends on how and to what extent the organic compounds are adsorbed onto the surfaces of calcite, quartz and clay. A model system of synthetic call cite, cyclohexane and the three probe molecules: benzoic acid, benzyl alcohol and benzylamine, have been...

  20. Potentials and Exploration Prospect of China's Hydrocarbon Resources

    Institute of Scientific and Technical Information of China (English)

    ZhangYiwei

    2004-01-01

    The potentials of China's hydrocarbon resources has risen as an important factor influencing the current policies of the country. China's oil industry is a developing industry. Gas reservoirs can be classified in light of their accumulation mechanisms into six types: water-sealed gas, hydrate, dissolved gas, conventional entrapped gas, capillary gas and adsorbed gas.

  1. Radiation induced inter-device leakage degradation

    Institute of Scientific and Technical Information of China (English)

    胡志远; 刘张李; 邵华; 张正选; 宁冰旭; 陈明; 毕大炜; 邹世昌

    2011-01-01

    The evolution of inter-device leakage generation technologies is studied with an N-type current with total ionizing dose in transistors in 180 nm poly-gate field device (PFD) that uses the shallow trench isolation as an effective gate oxide. The overall r

  2. Protection of window glass from acoustic leakage

    OpenAIRE

    Lych, Sergij; Rakobovchuk, Volodymyr

    2013-01-01

    In a survey was presented an analysis of the most common glass samples on the Ukrainian market on their protection level against leakage of acoustic information. The glass samples were studied by means of roentgen analysis, and the impact of elemental composition of glass according to a laser beam reflection factor was defined.

  3. Geological and Geochemical Studies of Heavy Oil Reservoirs in China

    Institute of Scientific and Technical Information of China (English)

    胡见义; 徐树宝; 等

    1989-01-01

    Thickened heavy oils in China are genetically characteristic of continenta .As to their physico-chemical properties,these oils are very high in viscosity and low in sulphur and trace element con-tents.In the group constituents,the concentrations of non-hydrocarbons and asphaltene are very high but those of saturated hydrocarbons and aromatics are very low.The gas chromatograms of alkanes show that these heavy oils have high abundances of iso-alkanes and cyclic hydrocarbons.In all the steroids and terpenoids ,bicyclic sesquiterpenoids,tricyclic diterpenoids,re-arranged steranes and gammacerane are strongly bildegradation-resistent.The formation of heavy oil reservoirs is controlled mainly by late basin ascendance,biodegradation,flushing by meteoric water and oxidation in the oil-bearing formations.Ac-cording to their formation mechanisms,heavy oil reservoirs can be classified as four categories:weathering and denudation,marginal oxidation,secondary migration and thickening of bottom water .Spacially,heavy thick oil reservoirs are distributed regularly:they usually show some paragenetic relationships with normal oil reservoirs.Heavy oil reservoirs often occur in structural highs or in overlying younger strata.Their burial depth is about 200m.Horizontally,most of them are distributed on the margins of basins or depressions.

  4. Improved reservoir exploitation

    Energy Technology Data Exchange (ETDEWEB)

    Thomassen, P.R. [IKU Petroleumsforskning A/S, Trondheim (Norway)

    1996-12-31

    This paper deals with reservoir exploitation and it highlights some ideas on how to improve exploitive skills to optimise the recovery of a field. The author looks closer at what needs to be done to optimise the reservoir data and the exploitation tools, and what are the needs of the reservoir production management. 2 refs., 3 figs.

  5. Volatile hydrocarbons inhibit methanogenic crude oil degradation

    Directory of Open Access Journals (Sweden)

    Angela eSherry

    2014-04-01

    Full Text Available Methanogenic degradation of crude oil in subsurface sediments occurs slowly, but without the need for exogenous electron acceptors, is sustained for long periods and has enormous economic and environmental consequences. Here we show that volatile hydrocarbons are inhibitory to methanogenic oil biodegradation by comparing degradation of an artificially weathered crude oil with volatile hydrocarbons removed, with the same oil that was not weathered. Volatile hydrocarbons (nC5-nC10, methylcyclohexane, benzene, toluene and xylenes were quantified in the headspace of microcosms. Aliphatic (n-alkanes nC12-nC34 and aromatic hydrocarbons (4-methylbiphenyl, 3-methylbiphenyl, 2-methylnaphthalene, 1-methylnaphthalene were quantified in the total hydrocarbon fraction extracted from the microcosms. 16S rRNA genes from key microorganisms known to play an important role in methanogenic alkane degradation (Smithella and Methanomicrobiales were quantified by quantitative PCR. Methane production from degradation of weathered oil in microcosms was rapid (1.1 ± 0.1 µmol CH4/g sediment/day with stoichiometric yields consistent with degradation of heavier n-alkanes (nC12-nC34. For non-weathered oil, degradation rates in microcosms were significantly lower (0.4 ± 0.3 µmol CH4/g sediment/day. This indicated that volatile hydrocarbons present in the non-weathered oil inhibit, but do not completely halt, methanogenic alkane biodegradation. These findings are significant with respect to rates of biodegradation of crude oils with abundant volatile hydrocarbons in anoxic, sulphate-depleted subsurface environments, such as contaminated marine sediments which have been entrained below the sulfate-reduction zone, as well as crude oil biodegradation in petroleum reservoirs and contaminated aquifers.

  6. Gas condensate reservoir characterisation for CO2 geological storage

    Science.gov (United States)

    Ivakhnenko, A. P.

    2012-04-01

    During oil and gas production hydrocarbon recovery efficiency is significantly increased by injecting miscible CO2 gas in order to displace hydrocarbons towards producing wells. This process of enhanced oil recovery (EOR) might be used for the total CO2 storage after complete hydrocarbon reservoir depletion. This kind of potential storage sites was selected for detailed studies, including generalised development study to investigate the applicability of CO2 for storages. The study is focused on compositional modelling to predict the miscibility pressures. We consider depleted gas condensate field in Kazakhstan as important target for CO2 storage and EOR. This reservoir being depleted below the dew point leads to retrograde condensate formed in the pore system. CO2 injection in the depleted gas condensate reservoirs may allow enhanced gas recovery by reservoir pressurisation and liquid re-vaporisation. In addition a number of geological and petrophysical parameters should satisfy storage requirements. Studied carbonate gas condensate and oil field has strong seal, good petrophysical parameters and already proven successful containment CO2 and sour gas in high pressure and high temperature (HPHT) conditions. The reservoir is isolated Lower Permian and Carboniferous carbonate platform covering an area of about 30 km. The reservoir contains a gas column about 1.5 km thick. Importantly, the strong massive sealing consists of the salt and shale seal. Sour gas that filled in the oil-saturated shale had an active role to form strong sealing. Two-stage hydrocarbon saturation of oil and later gas within the seal frame were accompanied by bitumen precipitation in shales forming a perfect additional seal. Field hydrocarbon production began three decades ago maintaining a strategy in full replacement of gas in order to maintain pressure of the reservoir above the dew point. This was partially due to the sour nature of the gas with CO2 content over 5%. Our models and

  7. Reservoir assessment of the Nubian sandstone reservoir in South Central Gulf of Suez, Egypt

    Science.gov (United States)

    El-Gendy, Nader; Barakat, Moataz; Abdallah, Hamed

    2017-05-01

    The Gulf of Suez is considered as one of the most important petroleum provinces in Egypt and contains the Saqqara and Edfu oil fields located in the South Central portion of the Gulf of Suez. The Nubian sandstone reservoir in the Gulf of Suez basin is well known for its great capability to store and produce large volumes of hydrocarbons. The Nubian sandstone overlies basement rocks throughout most of the Gulf of Suez region. It consists of a sequence of sandstones and shales of Paleozoic to Cretaceous age. The Nubian sandstone intersected in most wells has excellent reservoir characteristics. Its porosity is controlled by sedimentation style and diagenesis. The cementation materials are mainly kaolinite and quartz overgrowths. The permeability of the Nubian sandstone is mainly controlled by grain size, sorting, porosity and clay content especially kaolinite and decreases with increase of kaolinite. The permeability of the Nubian Sandstone is evaluated using the Nuclear Magnetic Resonance (NMR technology) and formation pressure data in addition to the conventional logs and the results were calibrated using core data. In this work, the Nubian sandstone was investigated and evaluated using complete suites of conventional and advanced logging techniques to understand its reservoir characteristics which have impact on economics of oil recovery. The Nubian reservoir has a complicated wettability nature which affects the petrophysical evaluation and reservoir productivity. So, understanding the reservoir wettability is very important for managing well performance, productivity and oil recovery.

  8. Status of Wheeler Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This is one in a series of status reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Wheeler Reservoir summarizes reservoir purposes and operation, reservoir and watershed characteristics, reservoir uses and use impairments, and water quality and aquatic biological conditions. The information presented here is from the most recent reports, publications, and original data available. If no recent data were available, historical data were summarized. If data were completely lacking, environmental professionals with special knowledge of the resource were interviewed. 12 refs., 2 figs.

  9. Status of Cherokee Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    This is the first in a series of reports prepared by Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overviews of Cherokee Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports, publications, and data available, and interviews with water resource professionals in various Federal, state, and local agencies and in public and private water supply and wastewater treatment facilities. 11 refs., 4 figs., 1 tab.

  10. Status of Cherokee Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-08-01

    This is the first in a series of reports prepared by Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overviews of Cherokee Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports, publications, and data available, and interviews with water resource professionals in various Federal, state, and local agencies and in public and private water supply and wastewater treatment facilities. 11 refs., 4 figs., 1 tab.

  11. Hydrocarbon Accumulation Conditions of Ordovician Carbonate in Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    LI Qiming; WU Guanghui; PANG Xiongqi; PAN Wenqin; LUO Chunshu; WANG Chenglin; LI Xinsheng; ZHOU Bo

    2010-01-01

    Based on comprehensive analysis of reservoir-forming conditions,the diversity of reservoir and the difference of multistage hydrocarbon charge are the key factors for the carbonate hydrocarbon accumulation of the Ordovician in the Tarim Basin.Undergone four major deposition-tectonic cycles,the Ordovician carbonate formed a stable structural framework with huge uplifts,in which are developed reservoirs of the reef-bank type and unconformity type,and resulted in multistage hydrocarbon charge and accumulation during the Caledonian,Late Hercynian and Late Himalayan.With low matrix porosity and permeability of the Ordovician carbonate,the secondary solution pores and caverns serve as the main reservoir space.The polyphase tectonic movements formed unconformity reservoirs widely distributed around the paleo-uplifts; and the reef-bank reservoir is controlled by two kinds of sedimentary facies belts,namely the steep slope and gentle slope.The unconventional carbonate pool is characterized by extensive distribution,no obvious edge water or bottom water,complicated oil/gas/water relations and severe heterogeneity controlled by reservoirs.The low porosity and low permeability reservoir together with multi-period hydrocarbon accumulation resulted in the difference and complex of the distribution and production of oil/gas/water.The distribution of hydrocarbon is controlled by the temporal-spatial relation between revolution of source rocks and paleo-uplifts.The heterogenetic carbonate reservoir and late-stage gas charge are the main factors making the oil/gas phase complicated.The slope areas of the paleo-uplifts formed in the Paleozoic are the main carbonate exploration directions based on comprehensive evaluation.The Ordovician of the northern slope of the Tazhong uplift,Lunnan and its periphery areas are practical exploration fields.The Yengimahalla-Hanikatam and Markit slopes are the important replacement targets for carbonate exploration.Gucheng,Tadong,the deep layers of

  12. Platelet function alterations in dengue are associated with plasma leakage

    NARCIS (Netherlands)

    Michels, M.; Alisjahbana, B.; Groot, P.G. de; Indrati, A.R.; Fijnheer, R.; Puspita, M.; Dewi, I.M.; Wijer, L. van de; Boer, E.M. de; Roest, M.; Ven, A.J. van der; Mast, Q. de

    2014-01-01

    Severe dengue is characterised by thrombocytopenia, plasma leakage and bleeding. Platelets are important for preservation of endothelial integrity. We hypothesised that platelet activation with secondary platelet dysfunction contribute to plasma leakage. In adult Indonesian patients with acute dengu

  13. Nonlinear Acoustics Used To Reduce Leakage Flow

    Science.gov (United States)

    Daniels, Christopher C.; Steinetz, Bruce M.

    2004-01-01

    Leakage and wear are two fundamental problems in all traditional turbine seals that contribute to an engine's inefficiency. The solutions to seal leakage and wear conflict in the conventional design space. Reducing the clearance between the seal and rotating shaft reduces leakage but increases wear because of increased contact incidents. Increasing the clearance to reduce the contact between parts reduces wear but increases parasitic leakage. The goal of this effort is to develop a seal that restricts leakage flow using acoustic pressure while operating in a noncontacting manner, thereby increasing life. In 1996, Dr. Timothy Lucas announced his discovery of a method to produce shock-free high-amplitude pressure waves. For the first time, the formation of large acoustic pressures was possible using dissonant resonators. A pre-prototype acoustic seal developed at the NASA Glenn Research Center exploits this fundamental acoustic discovery: a specially shaped cavity oscillated at the contained fluid's resonant frequency produces high-amplitude acoustic pressure waves of a magnitude approaching those required of today's seals. While the original researchers are continuing their development of acoustic pumps, refrigeration compressors, and electronic thermal management systems using this technology, the goal of researchers at Glenn is to apply these acoustic principles to a revolutionary sealing device. When the acoustic resonator shape is optimized for the sealing device, the flow from a high-pressure cavity to a low-pressure cavity will be restricted by a series of high-amplitude standing pressure waves of higher pressure than the pressure to be sealed. Since the sealing resonator cavity will not touch the adjacent sealing structures, seal wear will be eliminated, improving system life. Under a cooperative agreement between Glenn and the Ohio Aerospace Institute (OAI), an acoustic-based pre-prototype seal was demonstrated for the first time. A pressurized cavity was

  14. THE FINITE ELEMENT MODEL OF LEAKAGE PHENOMENA UNDER THE SOIL DAMS

    Directory of Open Access Journals (Sweden)

    Mahmud GÜNGÖR

    1995-01-01

    Full Text Available Dams can store billions and billions m3 of water in their reservoirs. So leakage phenomenon which threats the stabilitiy of building sould be well examined. In this paper, flow that occurs in the dam's body and at the bottom of dam as a result of leaking water from the earth filled dam's reservoir is examined numericaly. For this purpose, the finite elements model of the phenomenon has been set up with the help of a computer program, the mathematical equation for whole area was calculated, velocity and potential distribution of the flow in the dam's body and at the bottom were obtained. The values of pore water and leak pressure which were previously calculated by graphical method and hand drown flow net can be obtained more precisely by the use of velocity and potential valves obtained by finite element method which is used in this study.

  15. Modelling of Seismic and Resistivity Responses during the Injection of CO2 in Sandstone Reservoir

    Science.gov (United States)

    Omar, Muhamad Nizarul Idhafi Bin; Almanna Lubis, Luluan; Nur Arif Zanuri, Muhammad; Ghosh, Deva P.; Irawan, Sonny; Regassa Jufar, Shiferaw

    2016-07-01

    Enhanced oil recovery plays vital role in production phase in a producing oil field. Initially, in many cases hydrocarbon will naturally flow to the well as respect to the reservoir pressure. But over time, hydrocarbon flow to the well will decrease as the pressure decrease and require recovery method so called enhanced oil recovery (EOR) to recover the hydrocarbon flow. Generally, EOR works by injecting substances, such as carbon dioxide (CO2) to form a pressure difference to establish a constant productive flow of hydrocarbon to production well. Monitoring CO2 performance is crucial in ensuring the right trajectory and pressure differences are established to make sure the technique works in recovering hydrocarbon flow. In this paper, we work on computer simulation method in monitoring CO2 performance by seismic and resistivity model, enabling geoscientists and reservoir engineers to monitor production behaviour as respect to CO2 injection.

  16. 49 CFR 192.706 - Transmission lines: Leakage surveys.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Transmission lines: Leakage surveys. 192.706... Transmission lines: Leakage surveys. Leakage surveys of a transmission line must be conducted at intervals not exceeding 15 months, but at least once each calendar year. However, in the case of a transmission line...

  17. Junction leakage measurements with micro four-point probes

    DEFF Research Database (Denmark)

    Lin, Rong; Petersen, Dirch Hjorth; Wang, Fei

    2012-01-01

    We present a new, preparation-free method for measuring the leakage current density on ultra-shallow junctions. The junction leakage is found by making a series of four-point sheet resistance measurements on blanket wafers with variable electrode spacings. The leakage current density is calculate...

  18. Leakage Current Estimation of CMOS Circuit with Stack Effect

    Institute of Scientific and Technical Information of China (English)

    Yong-Jun Xu; Zu-Ying Luo; Xiao-Wei Li; Li-Jian Li; Xian-Long Hong

    2004-01-01

    Leakage current of CMOS circuit increases dramatically with the technology scaling down and has become a critical issue of high performance system. Subthreshold, gate and reverse biased junction band-to-band tunneling (BTBT) leakages are considered three main determinants of total leakage current. Up to now, how to accurately estimate leakage current of large-scale circuits within endurable time remains unsolved, even though accurate leakage models have been widely discussed. In this paper, the authors first dip into the stack effect of CMOS technology and propose a new simple gate-level leakage current model. Then, a table-lookup based total leakage current simulator is built up according to the model. To validate the simulator, accurate leakage current is simulated at circuit level using popular simulator HSPICE for comparison. Some further studies such as maximum leakage current estimation, minimum leakage current generation and a high-level average leakage current macromodel are introduced in detail. Experiments on ISCAS85 and ISCAS89 benchmarks demonstrate that the two proposed leakage current estimation methods are very accurate and efficient.

  19. Techniques for Leakage Power Reduction in Nanoscale Circuits: A Survey

    DEFF Research Database (Denmark)

    Liu, Wei

    This report surveys progress in the field of designing low power especially low leakage CMOS circuits in deep submicron era. The leakage mechanism and various recently proposed run time leakage reduction techniques are presented. Two designs from Cadence and Sony respectively, which can represent...... current industrial application of these techniques, are also illustrated....

  20. Measurement Methods to Determine Air Leakage Between Adjacent Zones

    Energy Technology Data Exchange (ETDEWEB)

    Hult, Erin L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dickerhoff, Darryl J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Phillip N. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-09-01

    Air leakage between adjacent zones of a building can lead to indoor air quality and energy efficiency concerns, however there is no existing standard for measuring inter-zonal leakage. In this study, synthesized data and field measurements are analyzed in order to explore the uncertainty associated with different methods for collecting and analyzing fan pressurization measurements to calculate interzone leakage.

  1. 3DHZETRN: Neutron leakage in finite objects.

    Science.gov (United States)

    Wilson, John W; Slaba, Tony C; Badavi, Francis F; Reddell, Brandon D; Bahadori, Amir A

    2015-11-01

    The 3DHZETRN formalism was recently developed as an extension to HZETRN with an emphasis on 3D corrections for neutrons and light ions. Comparisons to Monte Carlo (MC) simulations were used to verify the 3DHZETRN methodology in slab and spherical geometry, and it was shown that 3DHZETRN agrees with MC codes to the degree that various MC codes agree among themselves. One limitation of such comparisons is that all of the codes (3DHZETRN and three MC codes) utilize different nuclear models/databases; additionally, using a common nuclear model is impractical due to the complexity of the software. It is therefore difficult to ascertain if observed discrepancies are caused by transport code approximations or nuclear model differences. In particular, an important simplification in the 3DHZETRN formalism assumes that neutron production cross sections can be represented as the sum of forward and isotropic components, where the forward component is subsequently solved within the straight-ahead approximation. In the present report, previous transport model results in specific geometries are combined with additional results in related geometries to study neutron leakage using the Webber 1956 solar particle event as a source boundary condition. A ratio is defined to quantify the fractional neutron leakage at a point in a finite object relative to a semi-infinite slab geometry. Using the leakage ratio removes some of the dependence on the magnitude of the neutron production and clarifies the effects of angular scattering and absorption with regard to differences between the models. Discussion is given regarding observed differences between the MC codes and conclusions drawn about the need for further code development. Although the current version of 3DHZETRN is reasonably accurate compared to MC simulations, this study shows that improved leakage estimates can be obtained by replacing the isotropic/straight-ahead approximation with more detailed descriptions. Published by

  2. 3DHZETRN: Neutron leakage in finite objects

    Science.gov (United States)

    Wilson, John W.; Slaba, Tony C.; Badavi, Francis F.; Reddell, Brandon D.; Bahadori, Amir A.

    2015-11-01

    The 3DHZETRN formalism was recently developed as an extension to HZETRN with an emphasis on 3D corrections for neutrons and light ions. Comparisons to Monte Carlo (MC) simulations were used to verify the 3DHZETRN methodology in slab and spherical geometry, and it was shown that 3DHZETRN agrees with MC codes to the degree that various MC codes agree among themselves. One limitation of such comparisons is that all of the codes (3DHZETRN and three MC codes) utilize different nuclear models/databases; additionally, using a common nuclear model is impractical due to the complexity of the software. It is therefore difficult to ascertain if observed discrepancies are caused by transport code approximations or nuclear model differences. In particular, an important simplification in the 3DHZETRN formalism assumes that neutron production cross sections can be represented as the sum of forward and isotropic components, where the forward component is subsequently solved within the straight-ahead approximation. In the present report, previous transport model results in specific geometries are combined with additional results in related geometries to study neutron leakage using the Webber 1956 solar particle event as a source boundary condition. A ratio is defined to quantify the fractional neutron leakage at a point in a finite object relative to a semi-infinite slab geometry. Using the leakage ratio removes some of the dependence on the magnitude of the neutron production and clarifies the effects of angular scattering and absorption with regard to differences between the models. Discussion is given regarding observed differences between the MC codes and conclusions drawn about the need for further code development. Although the current version of 3DHZETRN is reasonably accurate compared to MC simulations, this study shows that improved leakage estimates can be obtained by replacing the isotropic/straight-ahead approximation with more detailed descriptions.

  3. DEVELOPMENT OF RESERVOIR CHARACTERIZATION TECHNIQUES AND PRODUCTION MODELS FOR EXPLOITING NATURALLY FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Wiggins; Raymon L. Brown; Faruk Civan; Richard G. Hughes

    2002-12-31

    For many years, geoscientists and engineers have undertaken research to characterize naturally fractured reservoirs. Geoscientists have focused on understanding the process of fracturing and the subsequent measurement and description of fracture characteristics. Engineers have concentrated on the fluid flow behavior in the fracture-porous media system and the development of models to predict the hydrocarbon production from these complex systems. This research attempts to integrate these two complementary views to develop a quantitative reservoir characterization methodology and flow performance model for naturally fractured reservoirs. The research has focused on estimating naturally fractured reservoir properties from seismic data, predicting fracture characteristics from well logs, and developing a naturally fractured reservoir simulator. It is important to develop techniques that can be applied to estimate the important parameters in predicting the performance of naturally fractured reservoirs. This project proposes a method to relate seismic properties to the elastic compliance and permeability of the reservoir based upon a sugar cube model. In addition, methods are presented to use conventional well logs to estimate localized fracture information for reservoir characterization purposes. The ability to estimate fracture information from conventional well logs is very important in older wells where data are often limited. Finally, a desktop naturally fractured reservoir simulator has been developed for the purpose of predicting the performance of these complex reservoirs. The simulator incorporates vertical and horizontal wellbore models, methods to handle matrix to fracture fluid transfer, and fracture permeability tensors. This research project has developed methods to characterize and study the performance of naturally fractured reservoirs that integrate geoscience and engineering data. This is an important step in developing exploitation strategies for

  4. Hydrocarbon Reserves: Abundance or Scarcity

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    impact on the growth of reserves and resources (H. Le Leuch); Additional reserves: the role of new technologies - A global perspective on EORIOR (G. Fries); - Updating reservoir models with dynamic data and uncertainty quantification: an integrated approach (F. Roggero); Seismic technology for the OAPEC countries (P. Canal); Exploration knowledge and technologies: impact of progress - Statistical results (N. Alazard); Stratigraphic modelling as a key to find new potentialities in exploration (D. Granjeon); Modelling hydrocarbon migration as a tool for reserve estimation (J-L. Rudkiewicz); The contribution of surface and near surface geology to hydrocarbon discoveries (S.M. Kumati); Contribution of the exploration activity in renewing reserves - The case of Algeria (R. Lounissi); Egypt's petroleum hydrocarbon potential (H. Hataba); Future of hydrocarbon reserves in Syria (T. Hemsh); Natural gas, the fuel of choice for decades to com (M.F. Chabrelie); The role and importance of Arab natural gas in world market (M. Al-Lababidi); LNG and GTL: two pathways for natural gas utilization (C. Cameron); Yet to find hydrocarbon potential (S. Al Menhali); Libyan context of hydrocarbon reserves: abundance or scarcity? (M. Elazi)

  5. Alopecia associated with unexpected leakage from electron cone

    Energy Technology Data Exchange (ETDEWEB)

    Wen, B.C.; Pennington, E.C.; Hussey, D.H.; Jani, S.K.

    1989-06-01

    Excessive irradiation due to unexpected leakage was found on a patient receiving electron beam therapy. The cause of this leakage was analyzed and the amount of leakage was measured for different electron beam energies. The highest leakage occurred with a 6 x 6 cm cone using a 12 MeV electron beam. The leakage dose measured along the side of the cone could be as great as 40%. Until the cones are modified or redesigned, it is advised that all patient setups be carefully reviewed to assure that no significant patient areas are in the side scatter region.

  6. Hydrocarbon potential of the Trinidad area - 1977

    Energy Technology Data Exchange (ETDEWEB)

    Persad, K.M.

    1978-06-01

    It is recognized that deltaic and associated sands, together with porous marine limestones, form the vast majority of the reservoirs in the major accumulations of hydrocarbons throughout the world. The source of the hydrocarbons is now thought to be kerogen which is generated from the organic content of principally marine shales which are formed in or near the continental shelves. The Trinidad area contains several sedimentary subbasins, most of which consist largely of deltaic and associated sediments. These sediments, like most of the ancient deltas of the world, contain major reserves of oil and gas. Other less important reserves should occur in sporadic (time-wise) porous limestones. The total proven and probable reserves of the Trinidad area are around 5 billion bbl of oil, of which 1.6 billion bbl already have been produced, and over 47 TCF of gas.

  7. Transport of reservoir fines

    DEFF Research Database (Denmark)

    Yuan, Hao; Shapiro, Alexander; Stenby, Erling Halfdan

    Modeling transport of reservoir fines is of great importance for evaluating the damage of production wells and infectivity decline. The conventional methodology accounts for neither the formation heterogeneity around the wells nor the reservoir fines’ heterogeneity. We have developed an integral...... dispersion equation in modeling the transport and the deposition of reservoir fines. It successfully predicts the unsymmetrical concentration profiles and the hyperexponential deposition in experiments....

  8. Integrated reservoir interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Caamano, Ed; Dickerman, Ken; Thornton, Mick (Conoco Indonesia Inc., Jakarta (Indonesia)); Corbett, Chip; Douglas, David; Schultz, Phil (GeoQuest, Houston, TX (United States)); Gir, Roopa; Nicholson, Barry (GeoQuest, Jakarta (Indonesia)); Martono, Dwi; Padmono, Joko; Novias; Kiagus; Suroso, Sigit (Pertamina Sumbagut, Brandan, North Sumatra (Indonesia)); Mathieu, Gilles (Etudes et Productions Schlumberger, Clamart (France)); Yan, Zhao (China National Petroleum Company, Beijing (China))

    1994-07-01

    Improved reservoir management often relies on linking a variety of application software that helps geoscientists handle, visualize and interpret massive amounts of diverse data. The goal is to obtain the best possible reservoir model so its behavior can be understood and optimized. But diverse application software creates specialty niches and discourages integrated interpretation. A description is given of a new reservoir management package that covers all required functionalities and encourages the geologist, geophysicist, petrophysicist and reservoir engineer to embrace the integrated approach. Case studies are included in the article. 21 figs., 13 refs.

  9. Project Boundary Setting and Leakage Treatment in CDM Project

    Institute of Scientific and Technical Information of China (English)

    ZOU Chen; WANG Shujuan; DUAN Maosheng; CHEN Changhe

    2005-01-01

    Project boundary setting and leakage treatment are two important issues to be considered when a clean development mechanism (CDM) project is being designed. There are still many uncertainties concerning these two issues. This paper reviews the concepts of project boundary setting and leakage in CDM projects, cites the types and sources of leakage, discusses the principles for determining leakage, and gives some proposed methods for dealing with leakage. A case study, using several steps to solve the boundary and leakage problems,shows how the analyzed principles and treatments can be implemented in a real project. Based on the result of the case study, the methods discussed are shown to be appropriate for settling leakage issues.

  10. Rationale for Measuring Duct Leakage Flows in Large Commercial Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Wray, Craig P.; Diamond, Richard C.; Sherman, Max H.

    2005-07-01

    Industry-wide methods of assessing duct leakage are based on duct pressurization tests, and focus on ''high pressure'' ducts. Even though ''low pressure'' ducts can be a large fraction of the system and tend to be leaky, few guidelines or construction specifications require testing these ducts. We report here on the measured leakage flows from ten large commercial duct systems at operating conditions: three had low leakage (less than 5% of duct inlet flow), and seven had substantial leakage (9 to 26%). By comparing these flows with leakage flows estimated using the industry method, we show that the latter method by itself is not a reliable indicator of whole-system leakage flow, and that leakage flows need to be measured.

  11. Characteristics of remaining oil viscosity in water-and polymer-flooding reservoirs in Daqing Oilfield

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The experimental analysis of 21 crude oil samples shows a good correlation between high molecular-weight hydrocarbon components (C 40+) and viscosity.Forty-four remaining oil samples extracted from oil sands of oilfield development coring wells were analyzed by high-temperature gas chromatography (HTGC),for the relative abundance of C 21-,C 21-C 40 and C 40+ hydrocarbons.The relationship between viscosity of crude oil and C 40+ (%) hydrocarbons abundance is used to expect the viscosity of remaining oil.The mobility characteristics of remaining oil,the properties of remaining oil,and the next displacement methods in reservoirs either water-flooded or polymer-flooded are studied with rock permeability,oil saturation of coring wells,etc.The experimental results show that the hydrocarbons composition,viscosity,and mobility of remaining oil from both polymer-flooding and water-flooding reservoirs are heterogeneous,especially the former.Relative abundance of C 21- and C 21-C 40 hydrocarbons in polymer-flooding reservoirs is lower than that of water-flooding,but with more abundance of C 40+ hydrocarbons.It is then suggested that polymer flooding must have driven more C 40- hydrocarbons out of reservoir,which resulted in relatively enriched C 40+,more viscous oils,and poorer mobility.Remaining oil in water-flooding reservoirs is dominated by moderate viscosity oil with some low viscosity oil,while polymer-flooding mainly contained moderate viscosity oil with some high viscosity oil.In each oilfield and reservoir,displacement methods of remaining oil,viscosity,and concentration by polymer-solution can be adjusted by current viscosity of remaining oil and mobility ratio in a favorable range.A new basis and methods are suggested for the further development and enhanced oil recovery of remaining oil.

  12. Angiographic leakage of polypoidal choroidal vasculopathy on indocyanine angiography

    Institute of Scientific and Technical Information of China (English)

    ZUO Cheng-guo; WEN Feng; HUANG Shi-zhou; LUO Guang-wei; YAN Hong; WU Wei-ju; WU De-zheng

    2010-01-01

    Background There is no detailed report about the angiographic leakage of polypoidal choroidal vasculopathy (PCV)lesions on indocyanine green (ICG) angiography. This study aimed to investigate the angiographic leakage of polypoidal lesions in PCV on ICG angiography.Methods One hundred and forty-four eyes of 137 patients diagnosed as PCV were prospectively observed. Fundus examination, fluorescein angiography, and ICG angiography were performed. Leakage of polypoidal lesions and clinical features were recorded according to the angiograms.Results In all 144 eyes, 110 eyes showed angiographic leakage (leakage group) on ICG angiography and three subtypes of leakage group were noted, which were polypoidal dilations leakage (47 eyes, 42.7%), branching vascular networks leakage (14 eyes, 12.7%) and leakage of both (49 eyes, 44.5%). The other 34 eyes showed regression of polypoidal lesions (regression group). In leakage group, the rates of pigment epithelial detachment (PED), best corrected visual acuity (BCVA) <0.1 and old subretinal hemorrhages were 56.4% (62 eyes), 19.1% (21 eyes), and 4.6% (5 eyes)respectively, compared with 8.8% (3 eyes), 50% (17 eyes) and 38.2% (13 eyes) of regression group (P <0.001). The history of regression group was significantly longer (P <0.001).Conclusions Angiographic leakage and regression can be observed in PCV lesions. Leakage of both polypoidal dilations and branching vascular networks is the most common subtype in leakage group. PCV in leakage group is more likely to be related to PED, better BCVA and shorter history, while PCV regression group tends to relevant to old subretinal hemorrhage, worse BCVA and longer history. This may reflect that the former is active or in the early course while the later is resting or in the late phase of PCV.

  13. A Numerical Study of Gas Injection and Caprock Leakage from Yort-e-Shah Aquifer in Iran

    Directory of Open Access Journals (Sweden)

    H. S. Rad

    2017-08-01

    Full Text Available In order to mitigate the adverse effects of global warming due to anthropogenic CO2 emission into the atmosphere, geological sequestration of CO2 into subsurface formations has been investigated by many studies over the last decade. However, selection of formations and sites for any field application is still open to debate. The most important properties of a formation suitable for carbon sequestration are those which impact the fluid flow processes. The injection or extraction of gas can change the pore pressure within the reservoir, which in turn results in redistribution of the stress field. These events may cause considerably leakage of the fluid into the surrounding geological formations or ground surface. The main objective of this paper is to evaluate the potential of Yort-e-Shah aquifer for CO2 storage, through a series of analyses with a simplified numerical model. The numerical results suggest that the optimum injection pressure in Yort-e-Shah aquifer is about 15.51 MPa with a safety factor of about 1.7. The results of the fluid pressure and gas plume expansion are presented. Also, an analysis was carried out for a case with leak through cap rock. When there is no leak, the pressure within the aquifer is stable, while on the other hand, the pressure in case of leakage is slightly smaller. In case of leakage, the pressure is lowest in the middle of the reservoir, mainly because the nodes at the middle of the aquifer are influenced by all the leakage points, while around the wellbore or near the end of gas plume, are affected less due to their longer distance to leakage points.

  14. Integrating gravimetric and interferometric synthetic aperture radar data for enhancing reservoir history matching of carbonate gas and volatile oil reservoirs

    KAUST Repository

    Katterbauer, Klemens

    2016-08-25

    Reservoir history matching is assuming a critical role in understanding reservoir characteristics, tracking water fronts, and forecasting production. While production data have been incorporated for matching reservoir production levels and estimating critical reservoir parameters, the sparse spatial nature of this dataset limits the efficiency of the history matching process. Recently, gravimetry techniques have significantly advanced to the point of providing measurement accuracy in the microgal range and consequently can be used for the tracking of gas displacement caused by water influx. While gravity measurements provide information on subsurface density changes, i.e., the composition of the reservoir, these data do only yield marginal information about temporal displacements of oil and inflowing water. We propose to complement gravimetric data with interferometric synthetic aperture radar surface deformation data to exploit the strong pressure deformation relationship for enhancing fluid flow direction forecasts. We have developed an ensemble Kalman-filter-based history matching framework for gas, gas condensate, and volatile oil reservoirs, which synergizes time-lapse gravity and interferometric synthetic aperture radar data for improved reservoir management and reservoir forecasts. Based on a dual state-parameter estimation algorithm separating the estimation of static reservoir parameters from the dynamic reservoir parameters, our numerical experiments demonstrate that history matching gravity measurements allow monitoring the density changes caused by oil-gas phase transition and water influx to determine the saturation levels, whereas the interferometric synthetic aperture radar measurements help to improve the forecasts of hydrocarbon production and water displacement directions. The reservoir estimates resulting from the dual filtering scheme are on average 20%-40% better than those from the joint estimation scheme, but require about a 30% increase in

  15. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    With the advancement in oil exploration,producible oil and gas are being found in low resistivity reservoirs,which may otherwise be erroneously thought as water zones from their resistivity.However,the evaluation of low resistivity reservoirs remains difficult from log interpretation.Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay,laminated shale,conductive matrix grains,microscopic capillary pores and high saline water,a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations.Herein,a generalized effective medium resistivity model has been proposed for low resistivity reservoirs,based on experimental measurements on artificial low resistivity shaly sand samples,symmetrical anisotropic effective medium theory for resistivity interpretations,and geneses and conductance mechanisms of low resistivity reservoirs.By analyzing effects of some factors on the proposed model,we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses.Also,shale distribution largely affects water saturation predicted by the model.Resistivity index decreases as fraction and conductivity of laminated shale,or fraction of dispersed clay,or conductivity of rock matrix grains increases.Resistivity index decreases as matrix percolation exponent,or percolation rate of capillary bound water increases,and as percolation exponent of capillary bound water,or matrix percolation rate,or free water percolation rate decreases.Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water,dispersed clay,microscopic capillary pores,laminated shale and conductive matrix grains,and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  16. Generalized effective medium resistivity model for low resistivity reservoir

    Institute of Scientific and Technical Information of China (English)

    SONG YanJie; TANG XiaoMin

    2008-01-01

    With the advancement in oil exploration, producible oil and gas are being found in low resistivity reservoirs, which may otherwise be erroneously thought as water zones from their resistivity. However,the evaluation of low resistivity reservoirs remains difficult from log interpretation. Since low resistivity in hydrocarbon bearing sands can be caused by dispersed clay, laminated shale, conductive matrix grains, microscopic capillary pores and high saline water, a new resistivity model is required for more accurate hydrocarbon saturation prediction for low resistivity formations. Herein, a generalized effective medium resistivity model has been proposed for low resistivity reservoirs, based on experimental measurements on artificial low resistivity shaly sand samples, symmetrical anisotropic effective medium theory for resistivity interpretations, and geneses and conductance mechanisms of low resistivity reservoirs. By analyzing effects of some factors on the proposed model, we show theoretically the model can describe conductance mechanisms of low resistivity reservoirs with five geneses. Also,shale distribution largely affects water saturation predicted by the model. Resistivity index decreases as fraction and conductivity of laminated shale, or fraction of dispersed clay, or conductivity of rock matrix grains increases. Resistivity index decreases as matrix percolation exponent, or percolation rate of capillary bound water increases, and as percolation exponent of capillary bound water, or matrix percolation rate, or free water percolation rate decreases. Rock sample data from low resistivity reservoirs with different geneses and interpretation results for log data show that the proposed model can be applied in low resistivity reservoirs containing high salinity water, dispersed clay, microscopic capillary pores, laminated shale and conductive matrix grains, and thus is considered as a generalized resistivity model for low resistivity reservoir evaluation.

  17. Pyritization effect on well logging parameters in Jurassic reservoirs within S-E Western Siberian oil fields

    Science.gov (United States)

    Janishevskii, A.; Ten, T.; Ezhova, A.

    2016-09-01

    Authigenic sulfide mineralization in hydrocarbon-saturated reservoirs distorts the electrical and density properties of rocks. The correlation between volumetric density, electro-conductive minerals and open porosity in 300 samples were determined. This fact made it possible to develop a nomograph in evaluating oil saturated reservoirs and could be applied in well geophysical survey data interpretation.

  18. Dynamic bayesian networks as a possible alternative to the ensemble kalman filter for parameter estimation in reservoir engineering

    NARCIS (Netherlands)

    Hanea, A.; Hanea, R.; Zilko, A.

    2012-01-01

    The objective of reservoir engineering is to optimize hydrocarbon recovery. One of the most common and efficient recovery processes is water injection. The water is pumped into the reservoir in injection wells in order to push the oil trapped in the porous media towards the production wells. The

  19. Dynamic bayesian networks as a possible alternative to the ensemble kalman filter for parameter estimation in reservoir engineering

    NARCIS (Netherlands)

    Hanea, A.; Hanea, R.; Zilko, A.

    2012-01-01

    The objective of reservoir engineering is to optimize hydrocarbon recovery. One of the most common and efficient recovery processes is water injection. The water is pumped into the reservoir in injection wells in order to push the oil trapped in the porous media towards the production wells. The mov

  20. Determination of Lateral Extension of Hydrocarbon Concentration Sealing Caprocks by AVO Analysis

    Institute of Scientific and Technical Information of China (English)

    Li Weilian

    2007-01-01

    The caprock is one of the key factors for a reservoir, especially for a gas reservoir. Whether the caprocks can block off the gas is of significance for the accumulation and preservation of the gas reservoir. In this paper, we use the Amplitude versus offset (AVO) seismic technique to determine the lateral extension of the hydrocarbon concentration sealing caprocks. The essence of this technique is to detect the variations of the reservoir bed physical properties by monitoring the variations of the reflection coefficient of seismic waves upon the interfaces between different lithologies.Generally it is used to indicate hydrocarbon directly. For the hydrocarbon concentration sealing caprocks, the change of hydrocarbon concentration may cause the change of physical properties of the caprocks. Therefore it is possible to evaluate the hydrocarbon concentration sealing ability of the caprocks by AVO. This paper presents a case study using AVO to determine the lateral extension of the hydrocarbon concentration sealing caprocks. The result shows that this method is helpful for the exploration of the region.

  1. Preliminary Geospatial Analysis of Arctic Ocean Hydrocarbon Resources

    Energy Technology Data Exchange (ETDEWEB)

    Long, Philip E.; Wurstner, Signe K.; Sullivan, E. C.; Schaef, Herbert T.; Bradley, Donald J.

    2008-10-01

    Ice coverage of the Arctic Ocean is predicted to become thinner and to cover less area with time. The combination of more ice-free waters for exploration and navigation, along with increasing demand for hydrocarbons and improvements in technologies for the discovery and exploitation of new hydrocarbon resources have focused attention on the hydrocarbon potential of the Arctic Basin and its margins. The purpose of this document is to 1) summarize results of a review of published hydrocarbon resources in the Arctic, including both conventional oil and gas and methane hydrates and 2) develop a set of digital maps of the hydrocarbon potential of the Arctic Ocean. These maps can be combined with predictions of ice-free areas to enable estimates of the likely regions and sequence of hydrocarbon production development in the Arctic. In this report, conventional oil and gas resources are explicitly linked with potential gas hydrate resources. This has not been attempted previously and is particularly powerful as the likelihood of gas production from marine gas hydrates increases. Available or planned infrastructure, such as pipelines, combined with the geospatial distribution of hydrocarbons is a very strong determinant of the temporal-spatial development of Arctic hydrocarbon resources. Significant unknowns decrease the certainty of predictions for development of hydrocarbon resources. These include: 1) Areas in the Russian Arctic that are poorly mapped, 2) Disputed ownership: primarily the Lomonosov Ridge, 3) Lack of detailed information on gas hydrate distribution, and 4) Technical risk associated with the ability to extract methane gas from gas hydrates. Logistics may control areas of exploration more than hydrocarbon potential. Accessibility, established ownership, and leasing of exploration blocks may trump quality of source rock, reservoir, and size of target. With this in mind, the main areas that are likely to be explored first are the Bering Strait and Chukchi

  2. Research Advances and Exploration Significance of Large-area Accumulation of Low and Medium Abundance Lithologic Reservoirs

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wenzhi; WANG Zecheng; WANG Hongjun; CHEN Mengjin

    2008-01-01

    In recent years, a series of large low and medium abundance oil and gas fields are discovered through exploration activities onshore China, which are commonly characterized by low porosity-permeability reservoirs, low oil/gas column height, multiple thin hydrocarbon layers, and distribution in overlapping and connection, and so on. The advantageous conditions for large-area accumulation of low-medium abundance hydrocarbon reservoirs include: (1) large (fan) delta sandbodies are developed in the hinterland of large flow-uncontrolled lake basins and they are alternated with source rocks extensively in a structure like "sandwiches"; (2) effective hydrocarbon source kitchens are extensively distributed, offering maximum contact chances with various sandbodies and hydrocarbon source rocks; (3) oil and gas columns are low in height, hydrocarbon layers are mainly of normal-low pressure, and requirements for seal rock are low; (4) reservoirs have strong inheterogeneity and gas reservoirs are badly connected; (5) the hydrocarbon desorption and expulsion under uplifting and unloading environments cause widely distributed hydrocarbon source rocks of coal measures to form large-area reservoirs; (6) deep basin areas and synclinal areas possess reservoir-forming dynamics. The areas with great exploration potential include the Paleozoic and Mesozoic in the Ordos Basin, the Xujiahe Formation in Dachuanzhong in the Sichuan basin, deep basin areas in the Songliao basin etc. The core techniques of improving exploration efficiency consist of the sweetspot prediction technique that focuses on fine characterization of reservoirs, the hydrocarbon layer protecting and high-speed drilling technique, and the rework technique for enhancing productivity.

  3. Stratigraphy and reservoir quality of the turbidite deposits, western sag, Bohai bay, China P.R.

    Science.gov (United States)

    Rotimi, Oluwatosin J.; Ako, Bankole D.; Zhenli, Wang

    2014-11-01

    Stratigraphic and subtle reservoirs such as pinchouts, sand lenses and unconformities have been discovered in Bohai basin. These reservoirs occur in sub-basins and sag structures called depressions. A prolific depression is the Liaohe depression that has been filled with rapidly changing mixed alluvial fan deposit of the Cenozoic age. Attempts made at recovering residual hydrocarbon from the subtle reservoir have necessitated the re-evaluation of available data to characterize and model the prolific Shahejie Formation turbidite deposit occurring as pinchouts and sand lenses for hydrocarbon assessment, reservoir quality and possible recovery through enhanced methods. Methods employed covered well logs analysis, clustering analysis for electrofacies and fuzzy logic analysis to predict missing log sections. Stratigraphic and structural analysis was done on SEGY 3D seismic volume after seismic to well tie. Stochastic simulation was done on both discrete and continuous upscaled data. This made it possible to correctly locate and laterally track identified reservoir formation on seismic data. Petrophysical parameters such as porosity and permeability were modeled with result of clustering analysis. Result shows that electrofacies converged on 2 rock classes. The area is characterized by the presence of interbeded sand-shale blanket formations serving as reservoir and seal bodies. The reservoir quality of the formations as seen on the petrophysical analysis done is replicated in simulation volume results. Reservoir rocks have porosity between 0.1 and 0.25, permeability between 1 and 2mD and hydrocarbon saturation as high as 89%. Lithofacies are observed to be laterally inconsistent, sub-parallel to dipping and occurring as porous and permeable continuous beds or pinchouts hosting hydrocarbon. The stochastic stratigraphic model depicts rock units in associations that are synsedimentary. The prevalent configuration gotten from the model gave an insight into exploring and

  4. Indian Ocean sources of Agulhas leakage

    Science.gov (United States)

    Durgadoo, Jonathan V.; Rühs, Siren; Biastoch, Arne; Böning, Claus W. B.

    2017-04-01

    We examine the mean pathways, transit timescales, and transformation of waters flowing from the Pacific and the marginal seas through the Indian Ocean (IO) on their way toward the South Atlantic within a high-resolution ocean/sea-ice model. The model fields are analyzed from a Lagrangian perspective where water volumes are tracked as they enter the IO. The IO contributes 12.6 Sv to Agulhas leakage, which within the model is 14.1 ± 2.2 Sv, the rest originates from the South Atlantic. The Indonesian Through-flow constitutes about half of the IO contribution, is surface bound, cools and salinificates as it leaves the basin within 10-30 years. Waters entering the IO south of Australia are at intermediate depths and maintain their temperature-salinity properties as they exit the basin within 15-35 years. Of these waters, the contribution from Tasman leakage is 1.4 Sv. The rest stem from recirculation from the frontal regions of the Southern Ocean. The marginal seas export 1.0 Sv into the Atlantic within 15-40 years, and the waters cool and freshen on-route. However, the model's simulation of waters from the Gulfs of Aden and Oman are too light and hence overly influenced by upper ocean circulations. In the Cape Basin, Agulhas leakage is well mixed. On-route, temperature-salinity transformations occur predominantly in the Arabian Sea and within the greater Agulhas Current region. Overall, the IO exports at least 7.9 Sv from the Pacific to the Atlantic, thereby quantifying the strength of the upper cell of the global conveyor belt.

  5. Oxygenated Derivatives of Hydrocarbons

    Science.gov (United States)

    For the book entitled “Insect Hydrocarbons: Biology, Biochemistry and Chemical Ecology”, this chapter presents a comprehensive review of the occurrence, structure and function of oxygenated derivatives of hydrocarbons. The book chapter focuses on the occurrence, structural identification and functi...

  6. Hydrocarbon Spectral Database

    Science.gov (United States)

    SRD 115 Hydrocarbon Spectral Database (Web, free access)   All of the rotational spectral lines observed and reported in the open literature for 91 hydrocarbon molecules have been tabulated. The isotopic molecular species, assigned quantum numbers, observed frequency, estimated measurement uncertainty and reference are given for each transition reported.

  7. EVA Suit Microbial Leakage Investigation Project

    Science.gov (United States)

    Falker, Jay; Baker, Christopher; Clayton, Ronald; Rucker, Michelle

    2016-01-01

    The objective of this project is to collect microbial samples from various EVA suits to determine how much microbial contamination is typically released during simulated planetary exploration activities. Data will be released to the planetary protection and science communities, and advanced EVA system designers. In the best case scenario, we will discover that very little microbial contamination leaks from our current or prototype suit designs, in the worst case scenario, we will identify leak paths, learn more about what affects leakage--and we'll have a new, flight-certified swab tool for our EVA toolbox.

  8. Diagenesis and Restructuring Mechanism of Oil and Gas Reservoir in the Marine Carbonate Formation, Northeastern Sichuan: A Case Study of the Puguang Gas Reservoir

    Institute of Scientific and Technical Information of China (English)

    DU Chunguo; WANG Jianjun; ZOU Huayao; ZHU Yangming; WANG Cunwu

    2009-01-01

    Based on the technology of balanced cross-section and physical simulation experiments associated with natural gas geochemical characteristic analyses, core and thin section observations, it has been proven that the Puguang gas reservoir has experienced two periods of diagenesis and restructuring since the Late lndo-Chinese epoch. One is the fluid transfer controlled by the tectonic movement and the other is geochemical reconstruction controlled by thermochemical sulfate reduction (TSR). The middle Yanshan epoch was the main period that the Puguang gas reservoir experienced the geochemical reaction of TSR. TSR can recreate the fluid in the gas reservoir, which makes the gas drying index higher and carbon isotope heavier because C_(2+) (ethane and heavy hydrocarbon) and ~(12)C (carbon 12 isotope) is first consumed relative to CH_4 and ~(13)C (carbon 13 isotope). However, the reciprocity between fluid regarding TSR (hydrocarbon, sulfureted hydrogen (H_2S), and water) and reservoir rock results in reservoir rock erosion and anhydrite alteration, which increases porosity in reservoir, thereby improving the petrophysical properties. Superimposed by later tectonic movement, the fluid in Puguang reservoir has twice experienced adjustment, one in the late Yanshan epoch to the early Himalayan epoch and the other time in late Himalayan epoch, after which Puguang gas reservoir is finally developed.

  9. Degradation of hydrocarbons under methanogenic conditions in different geosystems

    Science.gov (United States)

    Straaten, Nontje; Jiménez García, Núria; Richnow, Hans-Hermann; Krueger, Martin

    2014-05-01

    With increasing energy demand the search for new resources is becoming increasingly important for the future energy supply. Therefore the knowledge about fossil fuels like oil or natural gas and their extraction should be expanded. Biodegraded oil is found in many reservoirs worldwide. Consequently, it is very important to get insight in the microbial communities and metabolic processes involved in hydrocarbon degradation. Due to the lack of alternative electron acceptors in hydrocarbon-rich geosystems, degradation often takes place under methanogenic conditions. The aim of the present study is to identify the microorganisms and mechanisms involved in the degradation of complex hydrocarbons, like BTEX and polycyclic aromatic hydrocarbons, using culture dependent and independent techniques. For this purpose enrichment cultures from marine sediments, shales, coal and oil reservoirs are monitored for their capability to degrade alkanes and aromatic compounds. Moreover the environmental samples of these different geosystems analysed for evidence for the in situ occurrence of methanogenic oil degradation. The gas geochemical data provided in several cases hints for a recent biological origin of the methane present. First results of the microbial community analysis showed in environmental samples and enrichment cultures the existence of Bacteria known to degrade hydrocarbons. Also a diverse community of methanogenic Archaea could be found in the clone libraries. Additionally, in oil and coal reservoir samples the degradation of model hydrocarbons, e.g. methylnaphthalene, hexadecane and BTEX, to CH4 was confirmed by 13C-labeling. To explore the mechanisms involved in biodegradation, the enrichments as well as the original environmental samples are further analysed for the presence of respective functional genes.

  10. Reservoir Engineering Management Program

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J.H.; Schwarz, W.J.

    1977-12-14

    The Reservoir Engineering Management Program being conducted at Lawrence Berkeley Laboratory includes two major tasks: 1) the continuation of support to geothermal reservoir engineering related work, started under the NSF-RANN program and transferred to ERDA at the time of its formation; 2) the development and subsequent implementation of a broad plan for support of research in topics related to the exploitation of geothermal reservoirs. This plan is now known as the GREMP plan. Both the NSF-RANN legacies and GREMP are in direct support of the DOE/DGE mission in general and the goals of the Resource and Technology/Resource Exploitation and Assessment Branch in particular. These goals are to determine the magnitude and distribution of geothermal resources and reduce risk in their exploitation through improved understanding of generically different reservoir types. These goals are to be accomplished by: 1) the creation of a large data base about geothermal reservoirs, 2) improved tools and methods for gathering data on geothermal reservoirs, and 3) modeling of reservoirs and utilization options. The NSF legacies are more research and training oriented, and the GREMP is geared primarily to the practical development of the geothermal reservoirs. 2 tabs., 3 figs.

  11. Dynamic reservoir well interaction

    NARCIS (Netherlands)

    Sturm, W.L.; Belfroid, S.P.C.; Wolfswinkel, O. van; Peters, M.C.A.M.; Verhelst, F.J.P.C.M.

    2004-01-01

    In order to develop smart well control systems for unstable oil wells, realistic modeling of the dynamics of the well is essential. Most dynamic well models use a semi-steady state inflow model to describe the inflow of oil and gas from the reservoir. On the other hand, reservoir models use steady s

  12. Plasma devices for hydrocarbon reformation

    KAUST Repository

    Cha, Min Suk

    2017-02-16

    Plasma devices for hydrocarbon reformation are provided. Methods of using the devices for hydrocarbon reformation are also provided. The devices can include a liquid container to receive a hydrocarbon source, and a plasma torch configured to be submerged in the liquid. The plasma plume from the plasma torch can cause reformation of the hydrocarbon. The device can use a variety of plasma torches that can be arranged in a variety of positions in the liquid container. The devices can be used for the reformation of gaseous hydrocarbons and/or liquid hydrocarbons. The reformation can produce methane, lower hydrocarbons, higher hydrocarbons, hydrogen gas, water, carbon dioxide, carbon monoxide, or a combination thereof.

  13. Plant hydrocarbon recovery process

    Energy Technology Data Exchange (ETDEWEB)

    Dzadzic, P.M.; Price, M.C.; Shih, C.J.; Weil, T.A.

    1982-01-26

    A process for production and recovery of hydrocarbons from hydrocarbon-containing whole plants in a form suitable for use as chemical feedstocks or as hydrocarbon energy sources which process comprises: (A) pulverizing by grinding or chopping hydrocarbon-containing whole plants selected from the group consisting of euphorbiaceae, apocynaceae, asclepiadaceae, compositae, cactaceae and pinaceae families to a suitable particle size, (B) drying and preheating said particles in a reducing atmosphere under positive pressure (C) passing said particles through a thermal conversion zone containing a reducing atmosphere and with a residence time of 1 second to about 30 minutes at a temperature within the range of from about 200* C. To about 1000* C., (D) separately recovering the condensable vapors as liquids and the noncondensable gases in a condition suitable for use as chemical feedstocks or as hydrocarbon fuels.

  14. Geothermal reservoir engineering research

    Science.gov (United States)

    Ramey, H. J., Jr.; Kruger, P.; Brigham, W. E.; London, A. L.

    1974-01-01

    The Stanford University research program on the study of stimulation and reservoir engineering of geothermal resources commenced as an interdisciplinary program in September, 1972. The broad objectives of this program have been: (1) the development of experimental and computational data to evaluate the optimum performance of fracture-stimulated geothermal reservoirs; (2) the development of a geothermal reservoir model to evaluate important thermophysical, hydrodynamic, and chemical parameters based on fluid-energy-volume balances as part of standard reservoir engineering practice; and (3) the construction of a laboratory model of an explosion-produced chimney to obtain experimental data on the processes of in-place boiling, moving flash fronts, and two-phase flow in porous and fractured hydrothermal reservoirs.

  15. Leakage assessment in adjustable laparoscopic gastric banding: radiography versus {sup 99m}Tc-pertechnetate scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Van Den Bossche, B.; Goethals, I.; Dierckx, R.A.; Van de Wiele, C. [Division of Nuclear Medicine, Ghent University Hospital, De Pintelaan 185, 9000 Ghent (Belgium); Villeirs, G. [Department of Radiology, Ghent University Hospital, Ghent (Belgium); Pattyn, P. [Department of Surgery, Ghent University Hospital, Ghent (Belgium)

    2002-09-01

    The least invasive of all surgical weight-lowering procedures is the adjustable laparoscopic gastric banding (ALGB) technique. A rare complication (0.9%-1.8% of patients) but one that may require surgical revision is leakage of the gastric banding device. This paper reports on the usefulness of technetium-99m scintigraphy for the assessment of gastric band leaks as compared with radiography. Between March 1997 and October 2001, 23 obese patients (20 women and 3 men; mean age 35 years; range 23-60 years; mean body mass index before gastric banding procedure, 39.2 kg/m{sup 2}; range 29.3-52.1 kg/m{sup 2}) were referred for exclusion of gastric banding leakage by means of radiography and {sup 99m}Tc-pertechnetate scintigraphy. Both procedures were performed on the same day in all patients. Two patients underwent both procedures, respectively two and three times. A total of 27 radiographic and scintigraphic examinations were performed. Radiographs were judged positive for leakage when escape of contrast agent through a defect in the gastric banding device was visualised or when indirect criteria, e.g. smooth passage of barium suspension through the stoma after injection of contrast agent, were present. Scintigraphic images were judged positive when tracer disappearance out of the banding device and uptake in the thyroid gland as well as enhancement of the gastric mucosa were observed 30 min and/or 3 h post injection. Overall sensitivity, specificity and accuracy for radiography and {sup 99m}Tc scintigraphy were 81.8% vs 81.8%, 75% vs 100% and 77.7% vs 92.6%. Leakage from the reservoir or the connecting tube is a late complication of ALGB. The presented data suggest that {sup 99m}Tc-pertechnetate scintigraphy is more efficient than radiography in determining the presence of such leaks. (orig.)

  16. Modeling vapor dominated geothermal reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Marconcini, R.; McEdwards, D.; Neri, G.; Ruffilli, C.; Schroeder, R.; Weres, O.; Witherspoon, P.

    1977-09-12

    The unresolved questions with regard to vapor-dominated reservoir production and longevity are reviewed. The simulation of reservoir behavior and the LBL computer program are discussed. The geology of Serrazzano geothermal field and its reservoir simulation are described. (MHR)

  17. Integration of Seismic and Petrophysics to Characterize Reservoirs in “ALA” Oil Field, Niger Delta

    Directory of Open Access Journals (Sweden)

    P. A. Alao

    2013-01-01

    Full Text Available In the exploration and production business, by far the largest component of geophysical spending is driven by the need to characterize (potential reservoirs. The simple reason is that better reservoir characterization means higher success rates and fewer wells for reservoir exploitation. In this research work, seismic and well log data were integrated in characterizing the reservoirs on “ALA” field in Niger Delta. Three-dimensional seismic data was used to identify the faults and map the horizons. Petrophysical parameters and time-depth structure maps were obtained. Seismic attributes was also employed in characterizing the reservoirs. Seven hydrocarbon-bearing reservoirs with thickness ranging from 9.9 to 71.6 m were delineated. Structural maps of horizons in six wells containing hydrocarbon-bearing zones with tops and bottoms at range of −2,453 to −3,950 m were generated; this portrayed the trapping mechanism to be mainly fault-assisted anticlinal closures. The identified prospective zones have good porosity, permeability, and hydrocarbon saturation. The environments of deposition were identified from log shapes which indicate a transitional-to-deltaic depositional environment. In this research work, new prospects have been recommended for drilling and further research work. Geochemical and biostratigraphic studies should be done to better characterize the reservoirs and reliably interpret the depositional environments.

  18. CSF Leakage "Radiology, Neuroradiology and Head and Neck, ENT"

    Directory of Open Access Journals (Sweden)

    Jalal Jalal Shokouhi

    2009-01-01

    Full Text Available Introduction: Leak of CSF is a relatively common complication in skull base fractures and it is rarely seen during skull base tumors and pituitary gland pathologies "Adenomas and empty sellae syndrome"."nThe common site of CSF leakage is related to the site of fracture but it is more common in cribriform plate fractures. Other sites are frontal sinus fractures and rarely sphenoid sinus lesions related to pituitary gland site pathology. Evaluation of the cribriform plate and the posterior wall of the frontal sinus is an imaging key point."nOther rare conditions of CSF leak are related to temporal bone fractures leading to otorrhea and in a paradoxical feature with rhinorrhea "intact tympanic membrane with temporal bone fracture and eustachian tube transmission of fluid"."nEthiology "nTrauma and skull base fractures epecially in the cribriform plate."nParanasal sinus fractures specially in the frontal and sphenoidal sinuses."nTemporal bone fractures."nEmpty sellae and intrasellar tumors."nPost-op stage in the skull base tumors."nDiagnosis"nNasal CSF leakage laboratory."nRadioneucleid imaging: This way is sensitive but non-specific."nMethylen blue injection into CSF via lumbar puncture "non-specific" and rarely used."nHigh resolution axial, coronal and sagittal reconstructed images of skull base as a modality of choice"nIn case of positive CSF leak but negative spiral ultra-high resolution CT in PNS, ethmoidal region and cribriform plate also temporal bone cuts we need linear and pleuridirectional X-ray tomography."nIn case of positive CSF leakage and negative radiology and imaging it needs exploration surgery to direct vision of anterior fossa floor bones for fracture."n-Companion complication could be recurrent meningitis."n- No 3D-CT or MRI is necessary for bone fractures but MRI could be"nnecessary for related brain contusion or soft tissue lesions and tumor."nX-ray CT-cisternography"nAlthough more than 90% of fractures could be detected by

  19. Theoretical modeling of sliding vane compressor with leakage

    Energy Technology Data Exchange (ETDEWEB)

    Al-Hawaj, Osama [Department of Mechanical Engineering, University of Kuwait, P.O. Box 5969, Safat 13060 (Kuwait)

    2009-11-15

    Performance of a sliding vane compressor is significantly influenced by the leakage effect occurring between adjacent cells during the compression phase of the cycle. In this paper, thermodynamic and dynamical mathematical models were formulated for a double action sliding vane compressor including leakage effect modeling. The leakage modeling is incorporated through an analytic pressure model with a single tunable parameter to be adjusted to correspond with specific compressor leakage characteristics. The effect of leakage on the cell pressure, temperature, mass, and work, and total vane torque variations were qualitatively investigated. The study illustrated the significant effect of leakage on power input requirement, discharge pressure and mass delivery, and less significant effect on mechanical efficiency and specific mass delivery. The validity of the simulation results is made by comparing the pressure work calculated from both the thermodynamic and the dynamic models. (author)

  20. Residential Forced Air System Cabinet Leakage and Blower Performance

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain S.; Dickerhoff, Darryl J.; Delp, William W.

    2010-03-01

    This project evaluated the air leakage and electric power consumption of Residential HVAC components, with a particular focus on air leakage of furnace cabinets. Laboratory testing of HVAC components indicated that air leakage can be significant and highly variable from unit to unit ? indicating the need for a standard test method and specifying maximum allowable air leakage in California State energy codes. To further this effort, this project provided technical assistance for the development of a national standard for Residential HVAC equipment air leakage. This standard is being developed by ASHRAE and is called"ASHRAE Standard 193P - Method of test for Determining the Air Leakage Rate of HVAC Equipment". The final part of this project evaluated techniques for measurement of furnace blower power consumption. A draft test procedure for power consumption was developed in collaboration with the Canadian General Standards Board: CSA 823"Performance Standard for air handlers in residential space conditioning systems".

  1. Effects of water-supply reservoirs on streamflow in Massachusetts

    Science.gov (United States)

    Levin, Sara B.

    2016-10-06

    spillage under average pumping conditions from 2000 to 2004.For sites with insufficient data to simulate daily water balances, a proxy method to estimate the three spillage metrics was developed. A series of 4,000 Monte Carlo simulations of the reservoir water balance were run. In each simulation, streamflow, physical reservoir characteristics, and daily climate inputs were randomly varied. Tobit regression equations that quantify the relation between streamflow alteration and physical and operational characteristics of reservoirs were developed from the results of the Monte Carlo simulations and can be used to estimate each of the three spillage metrics using only the withdrawal ratio and the ratio of the surface area to the drainage area, which are available statewide for all reservoirs.A graphical user-interface for the Massachusetts Reservoir Simulation Tool was developed in a Microsoft Access environment. The simulation tool contains information for 70 reservoirs in Massachusetts and allows for simulation of additional scenarios than the ones considered in this report, including controlled releases, dam seepage and leakage, demand management plans, and alternative water withdrawal and transfer rules.

  2. Transanal stent in anterior resection does not prevent anastomotic leakage

    DEFF Research Database (Denmark)

    Bülow, Steffen; Bulut, O; Christensen, Ib Jarle;

    2006-01-01

    OBJECTIVE: A defunctioning transanal stent may theoretically reduce the leakage rate after anterior rectal resection. We present a randomized open study with the aim of comparing the leakage rate after anterior resection with a loop ileostomy, a transanal stent, both or neither. PATIENTS....... On this basis it was decided to discontinue the study prematurely for ethical reasons. CONCLUSION: Decompression of the anastomosis with a transanal stent does not reduce the risk of anastomotic leakage after anterior resection....

  3. Detection of Spectral Features of Anomalous Vegetation From Reflectance Spectroscopy Related to Pipeline Leakages

    Science.gov (United States)

    van der Meijde, M.; van der Werff, H. M.; Kooistra, J. F.

    2004-12-01

    Underground pipeline leakage inspection is an open problem with large economical and environmental impact. Traditional methods for investigating leakage and pollution, like drilling, are time consuming, destructive and expensive. A non-destructive and more economic exploration method would be a valuable complement to sub-surface investigative methods. Reflectance spectroscopy (or hyperspectral remote sensing) proved to be a tool that offers a non-destructive investigative method to identify anomalous spectral features in vegetation. One of the major environmental problems related to pipelines is the leakage of hydrocarbons into the environment. Hydrocarbons can establish locally anomalous zones that favor the development of a diverse array of chemical and mineralogical changes. Any vegetation present in these zones is likely to be influenced by the hostile and polluted environment. Geobotanical anomalies occur as a result of the effect of hydrocarbons on the growth of vegetation. The most likely changes in the vegetation are expected to occur in the chlorophyll concentrations which are an indicator of the health state. This is the main conclusion after an extensive field campaign in May 2004 in Holland investigating a 1 km trajectory of a 21 km long pipeline. The pipeline is `sweating' benzene condensates at approximately 50% of the connection points between the 9 meter segments of the pipeline. Spectral measurements were conducted at four different test locations in the 1 km trajectory. The test locations were covered by long grass, one of the fields was recently mown. Using different survey designs we can confirm the presence of geobotanical anomalies in different locations using various spectral interpretation techniques like linear red edge shifts, Carter stress indices, normalized difference vegetation index en yellowness index. After the interpretation of the geobotanical anomalies, derived from hyperspectral measurements, we compared the findings with

  4. Influence of Slot Defect Length on Magnetic Flux Leakage

    Institute of Scientific and Technical Information of China (English)

    Songling HUANG; Luming LI; Haiqing YANG; Keren SHI

    2004-01-01

    A key issue, which influences the applications of magnetic flux leakage testing, is defect quantification. There have been many research on the relationship between width, depth and magnetic flux leakage of slot defect. However, the length factor is often ignored. The relationship between characteristics of defect leakage field and defect length was investigated. The magnetic flux leakages of a series of plate specimens with the same width, same depth and different length slot defects were tested under the same magnetizing conditions. Testing results show that defect length is an important parameter needed to consider in quantifying defects.

  5. Hydrocarbon Development from Shale: A Set of Important, Unsolved Problems

    Science.gov (United States)

    Ingraffea, A. R.; Burchell, A.; Howarth, R.; Wilson, A.; Doe, P.; Colborn, T.; Wood, M. C.

    2013-12-01

    Hydraulic fracturing has become synonymous with the new technologies and processes used to develop oil and methane from shale formations. We will address the following important set of problems associated with such development and the role scientists are playing in communicating these to the public. Human Health Consequences: The health consequences of the wide-range of fugitive hydrocarbon emissions associated with methane and oil are not adequately addressed. New evidence about exposure to, and the known and possible health effects of, these toxic hitch hikers will be presented. Methane Emissions: Methane is a more powerful greenhouse gas than carbon dioxide, though atmospheric residence is shorter. Methane is emitted through-out the development life-cycle, albeit there is uncertainty over the rate, and short-term effect on global warming. Leakage from Faulty Wells: Multiple industry studies show that about 5 percent of oil and gas wells immediately leak methane and other fluids into the atmosphere and water wells due to integrity issues and increasing rates of leakage over time. With millions of wells drilled worldwide, and millions more expected, this problem is neither negligible nor preventable with current technology. Federal Exemptions and Home Rule: 'Fracking' currently slips through federal environmental statutory law because of an industry-friendly exemption. However, trusts are established in US law and the Public Trust Doctrine provides a basis for courts to enjoin 'fracking' due to the potential impact on beneficiaries of the trust --present and future generations. The public trust designates government as a trustee of crucial resources and imposes a fiduciary obligation on agencies to prevent "substantial impairment" of- and protect access to- clean air, clean water and other natural resources vital for public welfare and survival. Already applied to the realm of ecology, the doctrine is reviewed as a legal and policy toot to protect communities

  6. Facies-controlled volcanic reservoirs of northern Songliao Basin, NE China

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Volcanic rocks of the late Mesozoic are very important reservoirs for the commercial natural gases including hydrocarbon, carbon dioxide and rare gases in the northern Songliao Basin. The reservoir volcanic rocks include rhyolite,andesite, trachyte, basalt and tuff. Facies of the volcanic rocks can be classified into 5 categories and 15 special types.Porosity and permeability of the volcanic reservoirs are facies-controlled. Commercial reservoirs were commonly found among the following volcanic subfacies: volcanic neck (Ⅰ1), underground-explosive breccia (Ⅰ3), pyroclastic-bearing lava flow (Ⅱ3), upper effusive (Ⅲ3) and inner extrusive ones (Ⅳ1). The best volcanic reservoirs are generally evolved in the interbedded explosive and effusive volcanics. Rhyolites show in general better reservoir features than other types of rocks do.

  7. Metagenomics of hydrocarbon resource environments indicates aerobic taxa and genes to be unexpectedly common.

    Science.gov (United States)

    An, Dongshan; Caffrey, Sean M; Soh, Jung; Agrawal, Akhil; Brown, Damon; Budwill, Karen; Dong, Xiaoli; Dunfield, Peter F; Foght, Julia; Gieg, Lisa M; Hallam, Steven J; Hanson, Niels W; He, Zhiguo; Jack, Thomas R; Klassen, Jonathan; Konwar, Kishori M; Kuatsjah, Eugene; Li, Carmen; Larter, Steve; Leopatra, Verlyn; Nesbø, Camilla L; Oldenburg, Thomas; Pagé, Antoine P; Ramos-Padron, Esther; Rochman, Fauziah F; Saidi-Mehrabad, Alireeza; Sensen, Christoph W; Sipahimalani, Payal; Song, Young C; Wilson, Sandra; Wolbring, Gregor; Wong, Man-Ling; Voordouw, Gerrit

    2013-09-17

    Oil in subsurface reservoirs is biodegraded by resident microbial communities. Water-mediated, anaerobic conversion of hydrocarbons to methane and CO2, catalyzed by syntrophic bacteria and methanogenic archaea, is thought to be one of the dominant processes. We compared 160 microbial community compositions in ten hydrocarbon resource environments (HREs) and sequenced twelve metagenomes to characterize their metabolic potential. Although anaerobic communities were common, cores from oil sands and coal beds had unexpectedly high proportions of aerobic hydrocarbon-degrading bacteria. Likewise, most metagenomes had high proportions of genes for enzymes involved in aerobic hydrocarbon metabolism. Hence, although HREs may have been strictly anaerobic and typically methanogenic for much of their history, this may not hold today for coal beds and for the Alberta oil sands, one of the largest remaining oil reservoirs in the world. This finding may influence strategies to recover energy or chemicals from these HREs by in situ microbial processes.

  8. Second workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, P.; Ramey, H.J. Jr. (eds.)

    1976-12-03

    The Arab oil embargo of 1973 focused national attention on energy problems. A national focus on development of energy sources alternative to consumption of hydrocarbons led to the initiation of research studies of reservoir engineering of geothermal systems, funded by the National Science Foundation. At that time it appeared that only two significant reservoir engineering studies of geothermal reservoirs had been completed. Many meetings concerning development of geothermal resources were held from 1973 through the date of the first Stanford Geothermal Reservoir Engineering workshop December 15-17, 1975. These meetings were similar in that many reports dealt with the objectives of planned research projects rather than with results. The first reservoir engineering workshop held under the Stanford Geothermal Program was singular in that for the first time most participants were reporting on progress inactive research programs rather than on work planned. This was true for both laboratory experimental studies and for field experiments in producing geothermal systems. The Proceedings of the December 1975 workshop (SGP-TR-12) is a remarkable document in that results of both field operations and laboratory studies were freely presented and exchanged by all participants. With this in mind the second reservoir engineering workshop was planned for December 1976. The objectives were again two-fold. First, the workshop was designed as a forum to bring together researchers active in various physical and mathematical branches of the developing field of geothermal reservoir engineering, to give participants a current and updated view of progress being made in the field. The second purpose was to prepare this Proceedings of Summaries documenting the state of the art as of December 1976. The proceedings will be distributed to all interested members of the geothermal community involved in the development and utilization of the geothermal resources in the world. Many notable

  9. Perchlorate reduction by microbes inhabiting oil reservoirs

    Science.gov (United States)

    Liebensteiner, Martin; Stams, Alfons; Lomans, Bart

    2014-05-01

    Microbial perchlorate and chlorate reduction is a unique type of anaerobic respiration as during reduction of (per)chlorate chlorite is formed, which is then split into chloride and molecular oxygen. In recent years it was demonstrated that (per)chlorate-reducing bacteria may employ oxygenase-dependent pathways for the degradation of aromatic and aliphatic hydrocarbons. These findings suggested that (per)chlorate may be used as oxygen-releasing compound in anoxic environments that contain hydrocarbons, such as polluted soil sites and oil reservoirs. We started to study perchlorate reduction by microbes possibly inhabiting oil reservoirs. One of the organisms studied was Archaeoglobus fulgidus. This extremely thermophilic archaeon is known as a major contributor to souring in hot oil reservoirs. A. fulgidus turned out to be able to use perchlorate as terminal electron acceptor for growth with lactate (Liebensteiner et al 2013). Genome based physiological experiments indicated that A. fulgidus possesses a novel perchlorate reduction pathway. Perchlorate is first reduced to chlorite, but chlorite is not split into chloride and molecular oxygen as occurs in bacteria. Rather, chlorite reacts chemically with sulfide, forming oxidized sulfur compounds, which are reduced to sulfide in the electron transport chain by the archaeon. The dependence of perchlorate reduction on sulfur compounds could be shown. The implications of our findings as novel strategy for microbiological enhanced oil recovery and for souring mitigation are discussed. Liebensteiner MG, Pinkse MWH, Schaap PJ, Stams AJM and Lomans BP (2013) Archaeal (per)chlorate reduction at high temperature, a matter of abiotic-biotic reactions. Science 340: 85-87

  10. Appraisal of transport and deformation in shale reservoirs using natural noble gas tracers

    Energy Technology Data Exchange (ETDEWEB)

    Heath, Jason E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kuhlman, Kristopher L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Robinson, David G. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bauer, Stephen J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gardner, William Payton [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Univ. of Montana, Missoula, MT (United States)

    2015-09-01

    This report presents efforts to develop the use of in situ naturally-occurring noble gas tracers to evaluate transport mechanisms and deformation in shale hydrocarbon reservoirs. Noble gases are promising as shale reservoir diagnostic tools due to their sensitivity of transport to: shale pore structure; phase partitioning between groundwater, liquid, and gaseous hydrocarbons; and deformation from hydraulic fracturing. Approximately 1.5-year time-series of wellhead fluid samples were collected from two hydraulically-fractured wells. The noble gas compositions and isotopes suggest a strong signature of atmospheric contribution to the noble gases that mix with deep, old reservoir fluids. Complex mixing and transport of fracturing fluid and reservoir fluids occurs during production. Real-time laboratory measurements were performed on triaxially-deforming shale samples to link deformation behavior, transport, and gas tracer signatures. Finally, we present improved methods for production forecasts that borrow statistical strength from production data of nearby wells to reduce uncertainty in the forecasts.

  11. Reservoir characterization of Pennsylvanian sandstone reservoirs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.

    1995-02-01

    This final report summarizes the progress during the three years of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description; (ii) scale-up procedures; (iii) outcrop investigation. The first section describes the methods by which a reservoir can be described in three dimensions. The next step in reservoir description is to scale up reservoir properties for flow simulation. The second section addresses the issue of scale-up of reservoir properties once the spatial descriptions of properties are created. The last section describes the investigation of an outcrop.

  12. Development of leakage monitoring system using radioisotopes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. C.; Lee, D. S. [Seoil College, Seoul (Korea); Cho, Y. S. [Konyang University, Nonsan (Korea); Shin, S. K. [Sungkyunkwan Univ., Seoul (Korea)

    2000-04-01

    This study is to development the potable neutron back-scattering gauge for leakage and detecting liquid interface of an oil and liquid tank, using a radioisotopes. For this purpose, small sized, light weight potable gauge is to be designed as to develope neutron shielding mechanism, low power supply circuit, high voltage circuit, measurement circuit, and operating handle etc. The user will be able to set the duration of the time interval, the scale, the high voltage, the threshold, the channel window, the selection whether the data storage or not, the selection whether the scale, high voltage, threshold and window fix or not at any time. The counted pulse will be displayed with the numerical value and the line bar. The gauge will be able to connect to an IBM compatible PC via a serial port, power will be supplied by internal battery. 9 refs., 28 figs., 10 tabs. (Author)

  13. Leakages and pressure relation: an experimental research

    Directory of Open Access Journals (Sweden)

    F. De Paola

    2012-11-01

    Full Text Available Leaks in water systems are presently a frequent and increasing event that involves cost increase and poor service, not compliant to quality standards and modern management criteria. The most recent data available in Italy, resumed into the report issued by Control Committee for Water Resources Use (CONVIRI, shows leakages with an average value of 37%. It is therefore important, for maintenance perspective, to investigate occurrence and evolution of water leaks and the analytical link between leaks Qp and network pressure P, for a reliable calibration of water networks quali-quantitative simulation models. The present work reports the first results of an experimental campaign started at Laboratory of Hydraulics of Department of Hydraulics, Geotechnical and Environmental Engineering of University of Naples Federico II in order to analyze the features of Qp(P relation, which are compared with other results issued in literature.

  14. Leakage Resilient Secure Two-Party Computation

    DEFF Research Database (Denmark)

    Damgård, Ivan Bjerre; Hazay, Carmit; Patra, Arpita

    2012-01-01

    Definitions.} We formalize the notion of secure two-party computation in the presence of leakage and introduce security definitions in the {\\em ideal/real framework}. Our formalization induces two types of adversarial attacks. We further study the feasibility of our definitions in the computational setting......In the traditional {\\em secure function evaluation} setting, some set of distrusting parties jointly compute a function of their respective inputs {\\em securely} as if the computation is executed in an ideal setting where the parties send inputs to a trusted party that performs the computation...... and explore some of the conditions under which these definitions are met. \\item {\\em Composition Theorems.} We provide compositions theorems for our new modelings. Our results provide compositions theorems for the case where the inputs of the parties are sampled from a min-entropy source distribution. \\item...

  15. Leakages and pressure relations: an experimental research

    Directory of Open Access Journals (Sweden)

    F. De Paola

    2012-07-01

    Full Text Available Leaks in water systems are presently a frequent and increasing event that involves cost increase and poor service, not compliant to quality standards and modern management criteria. The most recent data available in Italy, resumed into the report issued by Control Committee for Water Resources Use (CONVIRI, shows leakages with an average value of 37%. It is important, for maintenance perspective, to investigate occurrence and evolution of water leaks and the analytical links between leaks Qp and network pressure P, for a reliable calibration of water networks quali-quantitative simulation models. The present work reports the results of an experimental campaign started at Laboratory of Hydraulic of Department of Hydraulic, Geotechnical and Environmental Engineering of University of Naples Federico II in order to analyze the features of Qp (P relation, which are compared with principal results issued in literature.

  16. Fluid leakage near the percolation threshold

    Science.gov (United States)

    Dapp, Wolf B.; Müser, Martin H.

    2016-02-01

    Percolation is a concept widely used in many fields of research and refers to the propagation of substances through porous media (e.g., coffee filtering), or the behaviour of complex networks (e.g., spreading of diseases). Percolation theory asserts that most percolative processes are universal, that is, the emergent powerlaws only depend on the general, statistical features of the macroscopic system, but not on specific details of the random realisation. In contrast, our computer simulations of the leakage through a seal—applying common assumptions of elasticity, contact mechanics, and fluid dynamics—show that the critical behaviour (how the flow ceases near the sealing point) solely depends on the microscopic details of the last constriction. It appears fundamentally impossible to accurately predict from statistical properties of the surfaces alone how strongly we have to tighten a water tap to make it stop dripping and also how it starts dripping once we loosen it again.

  17. Thraustochytrid protists degrade hydrocarbons

    Digital Repository Service at National Institute of Oceanography (India)

    Raikar, M.T.; Raghukumar, S.; Vani, V.; David, J.J.; Chandramohan, D.

    Although thraustochytrid protists are known to be of widespread occurrence in the sea, their hydrocarbon-degrading abilities have never been investigated. We isolated thraustochytrids from coastal waters and sediments of Goa coast by enriching MPN...

  18. Earthquakes and depleted gas reservoirs: which comes first?

    Directory of Open Access Journals (Sweden)

    M. Mucciarelli

    2014-12-01

    Full Text Available While scientists are paying increasing attention to the seismicity potentially induced by hydrocarbon exploitation, little is known about the reverse problem, i.e. the impact of active faulting and earthquakes on hydrocarbon reservoirs. The recent 2012 earthquakes in Emilia, Italy, raised concerns among the public for being possibly human-induced, but also shed light on the possible use of gas wells as a marker of the seismogenic potential of an active fold-and-thrust belt. Based on the analysis of over 400 borehole datasets from wells drilled along the Ferrara-Romagna Arc, a large oil and gas reserve in the southeastern Po Plain, we found that the 2012 earthquakes occurred within a cluster of sterile wells surrounded by productive ones. Since the geology of the productive and sterile areas is quite similar, we suggest that past earthquakes caused the loss of all natural gas from the potential reservoirs lying above their causative faults. Our findings have two important practical implications: (1 they may allow major seismogenic zones to be identified in areas of sparse seismicity, and (2 suggest that gas should be stored in exploited reservoirs rather than in sterile hydrocarbon traps or aquifers as this is likely to reduce the hazard of triggering significant earthquakes.

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

    Institute of Scientific and Technical Information of China (English)

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

    2008-01-01

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

  20. 构造因素对岩性油气藏形成的影响%INFLUENCE OF STRUCTURAL FACTORS ON FORMATION OF LITHOLOGIC RESERVOIRS

    Institute of Scientific and Technical Information of China (English)

    陈萍

    2011-01-01

    总结油气藏发现的历史及油气藏分类方法发现,经典油气藏概念是定义构造油藏的充分必要条件,缺少定义复杂油藏和岩性油气藏的充分条件.因此,采用油气藏的聚集原理对岩性油气藏研究中的理论问题进行了探讨,认为油气成藏的构造因素是浮力因素,岩性因素是储层孔隙结构因素;油气藏的形成过程是圈闭储集层中含油饱和度不断增加的过程;任何岩性油气藏的形成都不同程度地受到构造因素的影响,油气藏基本是随着构造的定型而定型.%Through the summary of discover history and classification methods of hydrocarbon reservoirs, it is found that the classic concept of hydrocarbon reservoirs is the necessary and sufficient condition to define the structural reservoirs, but it lacks the sufficient condition to define the complex and lithologic reservoirs. Therefore, this paper discusses the theoretical problems about the study of lithologic reservoirs through the application of hydrocarbon reservoir accumulation principle. It is considered that the structural factor of reservoir-forming is the buoyancy factor.The lithology factor is the one that influences reservoir pore structures. The forming process of hydrocarbon reservoirs is a continuous process of oil saturation increase in the volumetric reservoirs. The formation of any lithologic reservoirs is influenced by the structural factors to different extent. Hydrocarbon reservoirs are basically decided by the final formation of structures.

  1. Reservoir Characterization of the Lower Green River Formation, Southwest Uinta Basin, Utah

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Craig D.; Chidsey, Jr., Thomas C.; McClure, Kevin P.; Bereskin, S. Robert; Deo, Milind D.

    2002-12-02

    The objectives of the study were to increase both primary and secondary hydrocarbon recovery through improved characterization (at the regional, unit, interwell, well, and microscopic scale) of fluvial-deltaic lacustrine reservoirs, thereby preventing premature abandonment of producing wells. The study will encourage exploration and establishment of additional water-flood units throughout the southwest region of the Uinta Basin, and other areas with production from fluvial-deltaic reservoirs.

  2. Hydrocarbon migration characteristics of the Lower Cretaceous in the Erlian Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The paper systematically analyzes the hydrocarbon migration characteristics of the Lower Cretaceous in the Erlian Basin, based on the geochemical data of mudstone and sandstone in the main hydrocarbon-generating sags. (1) The source rocks in K1ba and K1bt1 are estimated to be the mature ones, their hydrocarbon expulsion ratio can reach 32%-72%. The Type-I sags in oil windows possess good hydrocarbon generation and expulsion conditions, where commercial reservoirs can be formed. (2) According to the curves of the mudstone compaction and evolution of clay minerals, the rapid compaction stage of mudstones is the right time of hydrocarbon expulsion, i.e., primary migration. (3) The timing between hydrocarbon generation and expulsion is mainly related to the accordance of the oil window and the rapid compaction stage of mudstones in the hydrocarbon generation sags of Type-I. That forms the most matching relation between hydrocarbon generation and migration. (4) The faults and unconformities are the important paths for the secondary hydrocarbon migration. Especially, the unconformity between K1ba and K1bt1 has a favorable condition for oil accumulation, where the traps of all types are the main exploration targets. (5) Hydrocarbon migration effect, in the Uliastai sag, is most significant; that in the Saihan Tal and Anan sags comes next, and that in the Bayandanan and Jargalangt sags is worst.

  3. Theory and Practice of a Leakage Resilient Masking Scheme

    DEFF Research Database (Denmark)

    Balasch, Josep; Faust, Sebastian; Gierlichs, Benedikt

    2012-01-01

    A recent trend in cryptography is to formally prove the leakage resilience of cryptographic implementations – that is, one formally shows that a scheme remains provably secure even in the presence of side channel leakage. Although many of the proposed schemes are secure in a surprisingly strong m...

  4. 75 FR 20546 - Total Inward Leakage Requirements for Respirators

    Science.gov (United States)

    2010-04-20

    ... HUMAN SERVICES 42 CFR Part 84 RIN 0920-AA33 Total Inward Leakage Requirements for Respirators AGENCY... Respirators,'' published in the Federal Register on October 30, 2009 (74 FR 56141). The comment period on this... total inward leakage (TIL) requirements for half-mask air-purifying particulate respirators approved...

  5. Mathematical approaches in deriving hydrocarbons expressions from seismic data

    Science.gov (United States)

    Farfour, Mohammed; Yoon, Wang Jung; Yoon-Geun, Lee, Jeong-Hwan

    2016-06-01

    Defining and understanding hydrocarbon expressions in seismic expression is main concern of geoscientists in oil and gas exploration and production. Over the last decades several mathematical approaches have been developed in this regard. Most of approaches have addressed information in amplitude of seismic data. Recently, more attention has been drawn towards frequency related information in order to extract frequency behaviors of hydrocarbons bearing sediments. Spectrally decomposing seismic data into individual frequencies found to be an excellent tool for investigating geological formations and their pore fluids. To accomplish this, several mathematical approaches have been invoked. Continuous wavelet transform and Short Time Window Fourier transform are widely used techniques for this purpose. This paper gives an overview of some widely used mathematical technique in hydrocarbon reservoir detection and mapping. This is followed by an application on real data from Boonsville field.

  6. Leakage-Aware Modulo Scheduling for Embedded VLIW Processors

    Institute of Scientific and Technical Information of China (English)

    Yong Guan; Jingling Xue

    2011-01-01

    As semi-conductor technologies move down to the nanometer scale, leakage power has become a significant component of the total power consumption. In this paper, we present a leakage-aware modulo scheduling algorithm to achieve leakage energy saving for applications with loops on Very Long Instruction Word (VLIW) architectures. The proposed algorithm is designed to maximize the idleness of function units integrated with the dual-threshold domino logic, and reduce the number of transitions between the active and sleep modes. We have implemented our technique in the Trimaran compiler and conducted experiments using a set of embedded benchmarks from DSPstone and Mibench on the cycle-accurate VLIW simulator of Trimaran. The results show that our technique achieves significant leakage energy saving compared with a previously published DAG-based (Directed Acyclic Graph) leakage-aware scheduling algorithm.

  7. Zigbee Technology in Intelligent Electric Leakage Protection System Applied Research

    Directory of Open Access Journals (Sweden)

    Deng Lei-lei

    2013-08-01

    Full Text Available Aiming at inconvenient wiring and low flexibility of current wired sensor network,An implementation method for real-time monitoring system based on ZigBee wireless network is proposed in this paper. in view of existing selective earth leakage protection device of low sensitivity, poor reliability problems, proposed one kind based on the zero sequence current feature selectionSelective leakage protection and line selection method; analysis of power supply system leakage fault branch of zero-sequence current logical relations, introduced based on the zero sequence current featuresVolume selective leakage protection principle and the realization method of fault line selection.As a Zigbee wireless sensor technology, Its application to the grid. Analyze leakage protection system in relation to the past system of superior performance and favorable conditions, And its features and system design of a simple program to explain the analysis and application of specific measures.  

  8. Reservoir characterization of hydraulic flow units in heavy-oil reservoirs at Petromonagas, eastern Orinoco belt, Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Merletti, G.D.; Hewitt, N.; Barrios, F.; Vega, V.; Carias, J. [BP Exploration, Houston, TX (United States); Bueno, J.C.; Lopez, L. [PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of)

    2009-07-01

    An accurate integrated reservoir description is necessary in extra-heavy oil prospects where pore throat geometries are the ultimate control on hydrocarbon primary recovery. The key element in producing accurate oil reservoir descriptions and improving productivity is to determine relationships between core-derived pore-throat parameters and log-derived macroscopic attributes. This paper described the use of the flow zone indicator technique (FZI) to identify hydraulic units within depositional facies. It focused on a petrophysical analysis aimed at improving the description of reservoir sandstones containing heavy or extra heavy oil in the eastern Orinoco belt in Venezuela. The Petromonagas license area contains large volumes of crude oil in-place with an API gravity of 8. Production comes primarily from the lowermost stratigraphic unit of the Oficina Formation, the Miocene Morichal Member. Facies analysis has revealed various depositional settings and core measurements depict a wide range in reservoir quality within specific depositional facies. The reservoir is divided into 4 different rock qualities and 5 associated non-reservoir rocks. The use of the FZI technique provides a better understanding of the relationship between petrophysical rock types and depositional facies. 4 refs., 4 tabs., 8 figs.

  9. The Attribute for Hydrocarbon Prediction Based on Attenuation

    Science.gov (United States)

    Hermana, Maman; Harith, Z. Z. T.; Sum, C. W.; Ghosh, D. P.

    2014-03-01

    Hydrocarbon prediction is a crucial issue in the oil and gas industry. Currently, the prediction of pore fluid and lithology are based on amplitude interpretation which has the potential to produce pitfalls in certain conditions of reservoir. Motivated by this fact, this work is directed to find out other attributes that can be used to reduce the pitfalls in the amplitude interpretation. Some seismic attributes were examined and studies showed that the attenuation attribute is a better attribute for hydrocarbon prediction. Theoretically, the attenuation mechanism of wave propagation is associated with the movement of fluid in the pore; hence the existence of hydrocarbon in the pore will be represented by attenuation attribute directly. In this paper we evaluated the feasibility of the quality factor ratio of P-wave and S-wave (Qp/Qs) as hydrocarbon indicator using well data and also we developed a new attribute based on attenuation for hydrocarbon prediction -- Normalized Energy Reduction Stack (NERS). To achieve these goals, this work was divided into 3 main parts; estimating the Qp/Qs on well log data, testing the new attribute in the synthetic data and applying the new attribute on real data in Malay Basin data. The result show that the Qp/Qs is better than Poisson's ratio and Lamda over Mu as hydrocarbon indicator. The curve, trend analysis and contrast of Qp/Qs is more powerful at distinguishing pore fluid than Poisson ratio and Lamda over Mu. The NERS attribute was successful in distinguishing the hydrocarbon from brine on synthetic data. Applying this attribute on real data on Malay basin, the NERS attribute is qualitatively conformable with the structure and location where the gas is predicted. The quantitative interpretation of this attribute for hydrocarbon prediction needs to be investigated further.

  10. Sedimentary charateristics and hydrocarbon accumulation in Northeast Sichuan basin

    Institute of Scientific and Technical Information of China (English)

    Jianming LI; Xiling WU; Rufeng LI; Liangjie TANG; Lei LI

    2008-01-01

    Northeast Sichuan basin is a Mesozoic-Cenozoic basin in the northern margin of the Yangtze plate which has a complex tectonic background and hydrocarbon accumulation history.By means of the analysis method of wave processes,major cycles of sedimentary wave process in this basin have been studied.The results show that there are five-order cycles corresponding to 760,220,100,35 and 20 Ma respectively,two first-order sedimentary cycles (220 Ma) and four secondorder sedimentary cycles (100 Ma).The authors find that the second-order sedimentary cycles are well matched with reservoir formation cycles through studying the relationship between second-order sedimentary cycles and reservoir formation cycles,and divide three reservoir formation cycles in this basin.

  11. Information Leakage Prevention Using Virtual Disk Drive

    Directory of Open Access Journals (Sweden)

    Tarek S. Sobh

    2013-06-01

    Full Text Available The worst news for information technology people are computer has been stolen or lost. The actual problem is the loss of the data stored on the hard drive that can fall into the wrong hands. However, users of information system and laptops computers are facing real problems with due to intruders using attack techniques when they are connected to the network and lost or stolen computers. In order to protect your organization against information leakage you should encrypt this data by only allowing the user with access to the encryption key to view the data, authorized application usage, and control who gets access to specific types of data. This work focuses on confidentiality of secure information storage. In addition, it presents the model to create of a Virtual Disk Drive (VDD on MS Windows, that appear to the user (after the mounting process as hard disks, but that are really stored as ciphered files on a file system. The proposed VDD prevents dictionary attacks and brute force attacks by incorporating a CAPTCHA (Completely Automated Public Turing test to tell Computers and Humans Apart in the login mechanism. The authentication method for the VDD login is based upon a 3-D image CAPTCHA. All components of this work are integrated in one security VDD tool called "SecDisk".

  12. Structural algorithm to reservoir reconstruction using passive seismic data (synthetic example)

    Energy Technology Data Exchange (ETDEWEB)

    Smaglichenko, Tatyana A.; Volodin, Igor A.; Lukyanitsa, Andrei A.; Smaglichenko, Alexander V.; Sayankina, Maria K. [Oil and Gas Research Institute, Russian Academy of Science, Gubkina str.3, 119333, Moscow (Russian Federation); Faculty of Computational Mathematics and Cybernetics, M.V. Lomonosov Moscow State University, Leninskie gory, 1, str.52,Second Teaching Building.119991 Moscow (Russian Federation); Shmidt' s Institute of Physics of the Earth, Russian Academy of Science, Bolshaya Gruzinskaya str. 10, str.1, 123995 Moscow (Russian Federation); Oil and Gas Research Institute, Russian Academy of Science, Gubkina str.3, 119333, Moscow (Russian Federation)

    2012-09-26

    Using of passive seismic observations to detect a reservoir is a new direction of prospecting and exploration of hydrocarbons. In order to identify thin reservoir model we applied the modification of Gaussian elimination method in conditions of incomplete synthetic data. Because of the singularity of a matrix conventional method does not work. Therefore structural algorithm has been developed by analyzing the given model as a complex model. Numerical results demonstrate of its advantage compared with usual way of solution. We conclude that the gas reservoir is reconstructed by retrieving of the image of encasing shale beneath it.

  13. Hydrocarbon-Derived Carbonate Cements of Subsurface Origin in the Vulcan Sub-Basin, Timor Sea

    Directory of Open Access Journals (Sweden)

    Shou-Yeh Gong

    2010-01-01

    Full Text Available Localized carbonate cementation occurs in the Eocene Grebe Sandstone of the Vulcan Sub-basin, Timor Sea, Australia. The cements have been previously interpreted as originating from microbial methane oxidation and sulfate reduction in a shallow subsurface environment and were related to hydrocarbon leakage. Here we reassess these localized carbonate cements in the Grebe Sandstone, and reported new findings. Petrography shows that there are two facies of sands in the Grebe Sandstone: (1 cemented, mostly fine-grained sands; and (2 loose, often coarse-grained sands. In addition, two types of carbonate matrix occur in the Grebe Sandstone: (1 spars to microspars in calcareous, fine-grained sandstones; and (2 micritic to microsparry matrix associated with limestone grains. Stable carbon isotopic values reveal that only the cements associated with sandstones were probably hydrocarbon-derived, and the resultant mineral is mainly calcite. Petrographic attributes and Mn+2 and Co+2 compositions of these cements differ significantly from those of modern cold-seep carbonates at or near the sea floor. Moreover, the hydrocarbon-derived carbonate mineralization only occurs in the fine-grained sands, not in the coarse-grained sands. In other word, the cementation was not only dependent on hydrocarbon leakage but also on the lithofacies of the host rock. We propose that the extent of hydrocarbon-related cementation alone cannot be used to evaluate the trap integrity as has been previously suggested.

  14. Geologic Characteristics of Gas Reservoirs in West Sichuan Foreland Basin

    Institute of Scientific and Technical Information of China (English)

    YANG Keming

    2008-01-01

    The foreland basin in West Sichuan is a tectonic unit that has undergone multi-periods tectonic movements of Indosinian-Yanshanian-Himalayan. Since late Triassic, it has been in a passive subsidence environment controlled by basin margin mountain systems and by the compression with abundant sediment sources. With the complex geologic setting, the main geologic characteristics of natural gas reservoir are listed as following:(1)Source rocks are coal-bearing mud and shale series with high to over maturity, and long and progressive hydrocarbon generation-displacement period. The key accumulation period is middle-late Yanshanian epoch.(2)There are three gas-bearing systems vertically, each of which has different reservoir mechanism, main-controlled factors and distribution law, so the exploration thoughts and techniques are also different.(3)Undergoing multi-period generation-migration-accumulation, oil and gas have encountered multi-period modification or destruction, and gas accumulation overpass multiple tectonic periods. So the trap type is complicated and dominated by combination traps. Because the main accumulation period of natural gas is early and the reservoir encountered the modification of strong Himalayan movement, there is great difference in the fullness degree of gas reservoirs and complicated gas-water relation. (4) Reservoir is tight to very tight, but reservoirs of relatively high quality developed under the super tight setting. (5) The key techniques for oil and gas exploration in west Sichuan foreland basin are the prediction of relatively favorable reservoirs, fractures and gas bearing; and the key techniques for oil and gas development are how to improve the penetration rate, reservoir protection and modification.

  15. Effect of retrograde gas condensate in low permeability natural gas reservoir; Efeito da condensacao retrograda em reservatorios de gas natural com baixa permeabilidade

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Paulo Lee K.C. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica; Ligero, Eliana L.; Schiozer, Denis J. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Engenharia de Petroleo

    2008-07-01

    Most of Brazilian gas fields are low-permeability or tight sandstone reservoirs and some of them should be gas condensate reservoir. In this type of natural gas reservoir, part of the gaseous hydrocarbon mixture is condensate and the liquid hydrocarbon accumulates near the well bore that causes the loss of productivity. The liquid hydrocarbon formation inside the reservoir should be well understood such as the knowledge of the variables that causes the condensate formation and its importance in the natural gas production. This work had as goal to better understanding the effect of condensate accumulation near a producer well. The influence of the porosity and the absolute permeability in the gas production was studied in three distinct gas reservoirs: a dry gas reservoir and two gas condensate reservoirs. The refinement of the simulation grid near the producer well was also investigated. The choice of simulation model was shown to be very important in the simulation of gas condensate reservoirs. The porosity was the little relevance in the gas production and in the liquid hydrocarbon formation; otherwise the permeability was very relevant. (author)

  16. Hydrocarbon Accumulation and Distribution Characteristics of the Silurian in the Tazhong Uplift of Tarim Basin

    Science.gov (United States)

    LÜ, Xiuxiang; BAI, Zhongkai; ZHAO, Fengyun

    Hydrocarbon accumulation of the Silurian in the Tazhong uplift of Tarim basin is characterized by "two sources and three stages". "Two sources" means that the hydrocarbons are derived from two source rocks of the Cambrian and Middle-Upper Ordovician. "Three stages" means that asphalt and movable oil undergoes three hydrocarbon accumulation stages, i.e., Late Caledonian, Late Hercynian, and Yanshanian-Himalayan. The formation of asphalt resulted from the destruction of the hydrocarbons accumulated and migrated in the early stages. The present movable oil, mostly derived from Middle-Upper Ordovician source rock, resulted from the hydrocarbons accumulated in the late stage. There are three types of reservoirs, i.e., anticline structural, stratigraphic lithological, and lava shield reservoirs in the Tazhong uplift. Hydrocarbon accumulation of the Silurian in the Tazhong uplift is controlled by the three factors. (1) The background of uplift structure. Around the ancient uplift, the compounding of many types makes up the composite hydrocarbon accumulation areas. (2) Effective cover. The show of oil gas including asphalt, heavy crude oil, and normal oil is quite active in the Silurian. Asphalt and heavy crude oil are distributed under the red mudstone member and movable oil is distributed under the gray mudstone member. (3) High quality reservoir bed. Sandstone is distributed widely in the Tazhong area. Reservoir pore space can be divided into three types: a) secondary origin-primary origin pore space; b) primary origin-secondary origin pore space, and c) micropore space. Porosity is 3.3-17.4%, and permeability is (0.1-667.97) × 10 -3 μm 2.

  17. Long-term monitoring of marine gas leakage

    Science.gov (United States)

    Spickenbom, Kai; Faber, Eckhard; Poggenburg, Jürgen; Seeger, Christian; Furche, Markus

    2010-05-01

    The sequestration of CO2 in sub-seabed geological formations is one of the Carbon Capture and Storage (CCS) strategies currently under study. Although offshore operations are significantly more expensive than comparable onshore operations, the growing public resistance against onshore CCS projects makes sub-seabed storage a promising option. Even after a thorough review of the geological setting, there is always the possibility of leakage from the reservoir. As part of the EU-financed project CO2ReMoVe (Research, Monitoring, Verification), which aims to develop innovative research and technologies for monitoring and verification of carbon dioxide geological storage, we are working on the development of submarine long-term gas flow monitoring systems. The basic design of the monitoring system builds on our experience in volcano monitoring. Early prototypes were composed of a raft floating on the surface of a mud volcano, carrying sensors for CO2 flux and concentration, data storage and transmission, and power supply by battery-buffered solar panels. The system was modified for installation in open sea by using a buoy instead of a raft and a funnel on the seafloor to collect the gas, connected by a flexible tube. This setup provides a cost-effective solution for shallow waters. However, a buoy interferes with ship traffic, and it is also difficult to adapt this design to greater water depths. These requirements can best be complied by a completely submersed system. A system for unattended long-term monitoring in a marine environment has to be extremely durable. Therefore, we focussed on developing a mechanically and electrically as simple setup as possible, which has the additional advantage of low cost. The system consists of a funnel-shaped gas collector, a sensor head and pressure housings for electronics and power supply. Since this setup is inexpensive, it can be deployed in numbers to cover larger areas. By addition of multi-channel data loggers, data

  18. Developement of leakage localization technique by using acoustic signal

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Y. H.; Jeon, J. H.; Seo, D. H.; Kim, K. W. [KAIST, Daejeon (Korea, Republic of)

    2010-07-15

    The objective of this research is to develop a leakage monitoring system for pipelines or valves in the secondary water system of a nuclear power plant. The system aims to detect the existence of leakage and to estimate the leak location, especially by utilizing the noise generated from the leak. It is safe, precise real-time alert system compared with the previous monitoring methods and tools such as the visual test and the thermal imaging camera. When there exists leakage in the pipeline or valves of nuclear power plant, the noise due to gas flow is radiated through leak region. That is, the secondary water system with leakage generates different noise from the system without leakage. This motivates us to measure and analyze the noise generated from the secondary water system, so as firstly to detect the existence of leakage, and secondly to estimate the leak location by using the noise source identification technique such as beamforming and acoustic holography. Especially the beamforming method models the signal from the noise source to estimate the location of source. Therefore, it is necessary to model the noise due to leakage which is dependent upon parameters. In the process of leak localization, the reflected wave due to interior walls and the measurement noise should be removed for the precise estimation. Therefore, we attempt to characterize the reflected wave and the measurement noise by modeling the interior sound field, thus to remove them and to localize the leak location with high precision

  19. Novel Sleep Transistor Techniques for Low Leakage Power Peripheral Circuits

    Directory of Open Access Journals (Sweden)

    Rajani H.P

    2012-09-01

    Full Text Available Static power consumption is a major concern in nanometre technologies. Along with technology scaling down and higher operating speeds of CMOS VLSI circuits, the leakage power is getting enhanced. As process geometries are becoming smaller, device density increases and threshold voltage as well as oxide thickness decrease to keep pace with performance. Two novel circuit techniques for leakage current reduction in inverters with and without state retention property are presented in this work. The powerdissipation during inactive (standby mode of operation can be significantly reduced compared to traditional power gating methods by these circuit techniques. The proposed circuit techniques are applied to inverters and the results are compared with earlier inverter leakage minimization techniques. Inverter buffer chains are designed using new state retention low leakage technique and found to be dissipatinglower power with state retention. All low leakage inverters are designed and simulated in cadence design environment using 90 nm technology files. The leakage power during sleep mode is found to be better by X 63 times for novel method. The total power dissipation has also reduced by a factor of X 3.5, compared to earlier sleepy keeper technique. The state retention feature is also good compared to earlier leakage power reduction methodologies.

  20. Novel Sleep Transistor Techniques for Low Leakage Power Peripheral Circuits

    Directory of Open Access Journals (Sweden)

    Rajani H.P

    2012-08-01

    Full Text Available Static power consumption is a major concern in nanometre technologies. Along with technology scaling down and higher operating speeds of CMOS VLSI circuits, the leakage power is getting enhanced. As process geometries are becoming smaller, device density increases and threshold voltage as well as oxide thickness decrease to keep pace with performance. Two novel circuit techniques for leakage current reduction in inverters with and without state retention property are presented in this work. The power dissipation during inactive (standby mode of operation can be significantly reduced compared to traditional power gating methods by these circuit techniques. The proposed circuit techniques are applied to inverters and the results are compared with earlier inverter leakage minimization techniques. Inverter buffer chains are designed using new state retention low leakage technique and found to be dissipating lower power with state retention. All low leakage inverters are designed and simulated in cadence design environment using 90 nm technology files. The leakage power during sleep mode is found to be better by X 63 times for novel method. The total power dissipation has also reduced by a factor of X 3.5, compared to earlier sleepy keeper technique. The state retention feature is also good compared to earlier leakage power reduction methodologies.

  1. Session: Reservoir Technology

    Energy Technology Data Exchange (ETDEWEB)

    Renner, Joel L.; Bodvarsson, Gudmundur S.; Wannamaker, Philip E.; Horne, Roland N.; Shook, G. Michael

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five papers: ''Reservoir Technology'' by Joel L. Renner; ''LBL Research on the Geysers: Conceptual Models, Simulation and Monitoring Studies'' by Gudmundur S. Bodvarsson; ''Geothermal Geophysical Research in Electrical Methods at UURI'' by Philip E. Wannamaker; ''Optimizing Reinjection Strategy at Palinpinon, Philippines Based on Chloride Data'' by Roland N. Horne; ''TETRAD Reservoir Simulation'' by G. Michael Shook

  2. Geothermal reservoir engineering

    CERN Document Server

    Grant, Malcolm Alister

    2011-01-01

    As nations alike struggle to diversify and secure their power portfolios, geothermal energy, the essentially limitless heat emanating from the earth itself, is being harnessed at an unprecedented rate.  For the last 25 years, engineers around the world tasked with taming this raw power have used Geothermal Reservoir Engineering as both a training manual and a professional reference.  This long-awaited second edition of Geothermal Reservoir Engineering is a practical guide to the issues and tasks geothermal engineers encounter in the course of their daily jobs. The bo

  3. Quantitative Hydrocarbon Surface Analysis

    Science.gov (United States)

    Douglas, Vonnie M.

    2000-01-01

    The elimination of ozone depleting substances, such as carbon tetrachloride, has resulted in the use of new analytical techniques for cleanliness verification and contamination sampling. The last remaining application at Rocketdyne which required a replacement technique was the quantitative analysis of hydrocarbons by infrared spectrometry. This application, which previously utilized carbon tetrachloride, was successfully modified using the SOC-400, a compact portable FTIR manufactured by Surface Optics Corporation. This instrument can quantitatively measure and identify hydrocarbons from solvent flush of hardware as well as directly analyze the surface of metallic components without the use of ozone depleting chemicals. Several sampling accessories are utilized to perform analysis for various applications.

  4. Miscellaneous hydrocarbon solvents.

    Science.gov (United States)

    Bebarta, Vikhyat; DeWitt, Christopher

    2004-08-01

    The solvents discussed in this article are common solvents not categorized as halogenated, aromatic, or botanical. The solvents discussed are categorized into two groups: hydrocarbon mixtures and single agents. The hydrocarbon mixtures discussed are Stoddard solvent, naphtha, and kerosene. The remaining solvents described are n-hexane, methyl n-butyl ketone, dimethylformamide, dimethyl sulfoxide, and butyl mercaptans. Effects common to this group of agents and their unique effects are characterized. Treatment of exposures and toxic effects of these solvents is described, and physiochemical properties and occupational exposure levels are listed.

  5. Seismic Evaluation of Hydorcarbon Saturation in Deep-Water Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Michael Batzle; D-h Han; R. Gibson; Huw James

    2005-10-31

    During this last quarter of the ''Seismic Evaluation of Hydrocarbon Saturation in Deep-Water Reservoirs'' project (Grant/Cooperative Agreement DE-FC26-02NT15342), we have moved forward on several fronts, including data acquisition as well as analysis and application. During this quarter we have: (1) Completed our site selection (finally); (2) Measured fluid effects in Troika deep water sand sample; (3) Applied the result to Ursa ''fizz gas'' zone; (4) Compared thin layer property averaging on AVO response; (5) Developed target oriented NMO stretch correction; (6) Examined thin bed effects on A-B crossplots; and (7) Begun incorporating outcrop descriptive models in seismic forward models. Several factors can contribute to limit our ability to extract accurate hydrocarbon saturations in deep water environments. Rock and fluid properties are one factor, since, for example, hydrocarbon properties will be considerably different with great depths (high pressure) when compared to shallow properties. Significant over pressure, on the other hand will make the rocks behave as if they were shallower. In addition to the physical properties, the scale and tuning will alter our hydrocarbon indicators. Reservoirs composed of thin bed effects will broaden the reflection amplitude distribution with incident angle. Normal move out (NMO) stretch corrections based on frequency shifts can be applied to offset this effect. Tuning will also disturb the location of extracted amplitudes on AVO intercept and gradient (A-B) plots. Many deep water reservoirs fall this tuning thickness range. Our goal for the remaining project period is to systematically combine and document these various effects for use in deep water exploration.

  6. Junction leakage measurements with micro four-point probes

    DEFF Research Database (Denmark)

    Lin, Rong; Petersen, Dirch Hjorth; Wang, Fei;

    2012-01-01

    We present a new, preparation-free method for measuring the leakage current density on ultra-shallow junctions. The junction leakage is found by making a series of four-point sheet resistance measurements on blanket wafers with variable electrode spacings. The leakage current density is calculated...... using a fit of the measured four-point resistances to an analytical two-sheet model. The validity of the approximation involved in the two-sheet model is verified by a comparison to finite element model calculations....

  7. Influence of nanomirelal phases on development processes of oil reservoirs in Volga-Ural region

    Science.gov (United States)

    Izotov, Victor; Sitdikova, Lyalya

    2010-05-01

    The optimisation of oil-field development by enhancing oil recovery is the most important target in further improvement of oil production processes. The resulting economic benefits often exceed those from discoveries of new fields, especially in hard-to-reach regions. Despite the wide use of enhanced oil recovery methods, their efficiency is in many cases not as high as expected. For instance, in terrigenous reservoirs of the Volga-Ural region oil recovery rarely exceeds 0.4, and in carbonate reservoirs with the complex structure, variability and high oil viscosity it can be as low as 0.15-0.20. In natural bitumen fields, the recovery factor is even lower. Analysis of the conducted EOR optimisation operations indicates that EOR methods mainly aim to change the hydrodynamic conditions in the reservoir under development or the physicochemical properties of oil, - for instance, to decrease its viscosity or to change its lyophilic behaviour. The impact of EOR methods on the reservoir's mineral component remains largely unstudied. It is generally believed that the mineral component of the reservoir, its matrix, is inert and remains unaffected by EOR methods. However, the analysis of oil-field development processes and the available studies allow the conclusion that natural hydrocarbon reservoirs are sensitive to any impact on both the near-wellbore zone and the whole reservoir. The authors' research in the reservoir's mineral phase dynamics has permitted the conclusion that the reservoir's fluid phases (including hydrocarbons) and the reservoir itself form a lithogeochemical system that remains in unstable equilibrium. Any external impact, such as the reservoir penetration or the use of EOR methods, disturbs this equilibrium and changes the filtration characteristics of the reservoir, the fluid chemistry and the reaction of the reservoir's mineral component to the impact. In order to characterise the processes in the reservoir in the course of its development, the

  8. A Percolation Study of Wettability Effect on the Electrical Properties of Reservoir Rocks

    DEFF Research Database (Denmark)

    Zhou, Dengen; Arbabi, Sepehr; Stenby, Erling Halfdan

    1997-01-01

    Measurements of the electrical resistivity of oil reservoirs are commonly used to estimate other properties of reservoirs, such as porosity and hydrocarbon reserves. However, the interpretation of the measurements is based on empirical correlations, because the underlying mechanisms that control...... the electrical properties of oil bearing rocks have not been well understood. In this paper, we employ percolation concepts to investigate the effect of wettability on the electrical conductivity of a reservoir formation. A three-dimensional simple cubic network is used to represent an ideal reservoir formation...... behavior of reservoir resistivities of different wettabilities. It demonstrates that the resistivity index depends on saturation history and wettability. For strongly oil-wet systems, significant hysteresis is expected, while there is little hysteresis for strongly water-wet systems, and some hysteresis...

  9. Iron speciation and mineral characterization of upper Jurassic reservoir rocks in the Minhe Basin, NW China

    Science.gov (United States)

    Ma, Xiangxian; Zheng, Guodong; Xu, Wang; Liang, Minliang; Fan, Qiaohui; Wu, Yingzhong; Ye, Conglin; Shozugawa, Katsumi; Matsuo, Motoyuki

    2016-12-01

    Six samples from a natural outcrop of reservoir rocks with oil seepage and two control samples from surrounding area in the Minhe Basin, northwestern China were selectively collected and analyzed for mineralogical composition as well as iron speciation using X-ray powder diffraction (XRD) and Mössbauer spectroscopy, respectively. Iron species revealed that: (1) the oil-bearing reservoir rocks were changed by water-rock-oil interactions; (2) even in the same site, there was a different performance between sandstone and mudstone during the oil and gas infusion to the reservoirs; and (3) this was evidence indicating the selective channels of hydrocarbon migration. In addition, these studies showed that the iron speciation by Mössbauer spectroscopy could be useful for the study of oil and gas reservoirs, especially the processes of the water-rock interactions within petroleum reservoirs.

  10. Iron speciation and mineral characterization of upper Jurassic reservoir rocks in the Minhe Basin, NW China

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xiangxian; Zheng, Guodong, E-mail: gdzhbj@mail.iggcas.ac.cn; Xu, Wang [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Liang, Minliang [Chinese Academy of Geological Sciences, Institute of Geomechanics, Key Lab of Shale Oil and Gas Geological Survey (China); Fan, Qiaohui; Wu, Yingzhong; Ye, Conglin [Chinese Academy of Sciences, Key Laboratory of Petroleum Resources, Gansu Province / Key Laboratory of Petroleum Resources Research, Institute of Geology and Geophysics (China); Shozugawa, Katsumi; Matsuo, Motoyuki [The University of Tokyo, Graduate School of Arts and Sciences (Japan)

    2016-12-15

    Six samples from a natural outcrop of reservoir rocks with oil seepage and two control samples from surrounding area in the Minhe Basin, northwestern China were selectively collected and analyzed for mineralogical composition as well as iron speciation using X-ray powder diffraction (XRD) and Mössbauer spectroscopy, respectively. Iron species revealed that: (1) the oil-bearing reservoir rocks were changed by water-rock-oil interactions; (2) even in the same site, there was a different performance between sandstone and mudstone during the oil and gas infusion to the reservoirs; and (3) this was evidence indicating the selective channels of hydrocarbon migration. In addition, these studies showed that the iron speciation by Mössbauer spectroscopy could be useful for the study of oil and gas reservoirs, especially the processes of the water-rock interactions within petroleum reservoirs.

  11. A new array system for multiphysics (MT, LOTEM, and microseismics) with focus on reservoir monitoring

    Science.gov (United States)

    Strack, K.; Davydycheva, S.; Hanstein, T.; Smirnov, M.

    2017-07-01

    Over the last 6 years we developed an array system for electromagnetic acquisition (magnetotelluric & long offset transient electromagnetics [LOTEM]) that includes microseismic acquisition. While predominantly used for magnetotellurics, we focus on the autonomous operation as reservoir monitoring system including a shallow borehole receiver and 100/150 KVA transmitter. A marine extension is also under development. For Enhanced Oil recovery (EOR), in addition to reservoir flood front movements, reservoir seal integrity has become an issue [1]. Seal integrity is best addressed with microseismics while the water flood front is best addressed with electromagnetics. Since the flooded reservoir is conductive and the hydrocarbon saturated part is resistive, you need both magnetic and electric fields. The fluid imaging is addressed using electromagnetics. To overcome the volume-focus inherent to electromagnetics a new methodology to focus the sensitivity under the receiver is proposed. Field data and 3D modeling confirm this could increase the efficiency of LOTEM to reservoir monitoring.

  12. 4D seismic reservoir characterization, integrated with geo-mechanical modelling

    NARCIS (Netherlands)

    Angelov, P. V.

    2009-01-01

    Hydrocarbon production induces time-lapse changes in the seismic attributes (travel time and amplitude) both at the level of the producing reservoir and in the surrounding rock. The detected time-lapse changes in the seismic are induced from the changes in the petrophysical properties of the rock,

  13. 4D seismic reservoir characterization, integrated with geo-mechanical modelling

    NARCIS (Netherlands)

    Angelov, P. V.

    2009-01-01

    Hydrocarbon production induces time-lapse changes in the seismic attributes (travel time and amplitude) both at the level of the producing reservoir and in the surrounding rock. The detected time-lapse changes in the seismic are induced from the changes in the petrophysical properties of the rock, i

  14. Exploiting the airwave for time-lapse reservoir monitoring with CSEM on land

    NARCIS (Netherlands)

    Wirianto, M.; Mulder, W.A.; Slob, E.C.

    2011-01-01

    In the application of controlled source electromagnetics for reservoir monitoring on land, repeatability errors in the source will mask the time-lapse signal due to hydrocarbon production when recording surface data close to the source. We demonstrate that at larger distances, the airwave will still

  15. Diagenesis and application of LiDAR in reservoir analogue studies: karstification in the Cretaceous Apulia carbonate platform dolomitization in the Triassic Latemar carbonate buildup

    OpenAIRE

    Jacquemyn, Carl

    2013-01-01

    The ever-increasing demand for energy and hydrocarbons coincides with gradual depletion of currently producing conventional oil and gas reservoirs. Therefore new exploration plays are extended to more complex oil and gas plays, such as karstified limestones and hydrothermal dolomites. Furthermore production from currently producing reservoirs is optimized by revisiting or improving the geological knowledge of these reservoirs. These two perspectives are covered in this study on dolomitization...

  16. Hydrocarbon accumulation in deep fluid modified carbonate rock in the Tarim Basin

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The activities of deep fluid are regionalized in the Tarim Basin. By analyzing the REE in core samples and crude oil, carbon isotope of carbon dioxide and inclusion temperature measurement in the west of the Tazhong Uplift in the western Tarim Basin, all the evidence confirms the existence of deep fluid. The deep fluid below the basin floor moved up into the basin through discordogenic fauit and volcanicity to cause corrosion and metaaomatosis of carbonate rock by exchange of matter and energy. The pore structure and permeability of the carbonate reservoirs were improved, making the carbonate reservoirs an excellent type of deeply buried modification. The fluorite ore belts discovered along the large fault and the volcanic area in the west of the Tazhong Uplift are the outcome of deep fluid action. Such carbonate reservoirs are the main type of reservoirs in the Tazhong 45 oilfield. The carbonate reservoirs in well YM 7 are improved obviously by thermal fluid dolomitization. The origin and territory of deep fluid are associated with the discordogenic fault and volcanicity in the basin. The discordogenic fault and volcanic area may be the pointer of looking for the deep fluid modified reservoirs. The primary characteristics of hydrocarbon accumulation in deep fluid reconstructed carbonate rock are summarized as accumulation near the large fault and volcano passage, late-period hydrocarbon accumulation after volcanic activity, and subtle trap reservoirs controlled by lithology.

  17. SILTATION IN RESERVOIRS

    African Journals Online (AJOL)

    human resources. It is also intended to make known to the general public that ... port processes were not properly taken into account. ... Studies carried out on 19 reservoirs in Cen- tral Europe with storage capacity ranging be- tween 1.48 x ...

  18. Impactos de la explotación de reservorios no convencionales de hidrocarburos sobre la actividad industrial y de servicios en el sistema de ciudades. El caso de la Cuenca Neuquina en la Patagonia Argentina / Impacts of the exploitation of unconventional hydrocarbon reservoirs on industrial activity and services in the city system: the case of the Neuquen Basin in Patagonia Argentina

    Directory of Open Access Journals (Sweden)

    Susana Graciela Landriscini

    2016-12-01

    un conjunto de centros menores lo hacen como proveedores locales. Se aborda asimismo el rol de los parques industriales en el ordenamiento territorial y en el desenvolvimiento de la cadena hidrocarburífera. Abstract This paper presents advances in knowledge about the impact of exploration and exploitation of hydrocarbons from unconventional reservoirs in Argentina Neuquen Basin. Recent changes focus on the system of cities Confluence Neuquen and frames companies that make up the value chain. Such impact also extends to settled rionegrinas localities in Cuenca, extended to the south of the province of Mendoza and western provinces of La Pampa and Rio Black. theoretical debates about the functions of cities, the weight of the trajectory and agglomeration phenomena, the changes that are generated as part of networks and flows in times of globalization are taken up again; and issues of knowledge management and innovation capabilities of small and medium enterprises that make up the territorial productive and institutional system. Documents, plans and programs on the region and the supplier / customer relationships in the upstream are reviewed, and reflects on the tensions generated by these processes, and the prospects for transforming the regional urban system in its current stage of development. The assessment of urban changes related activities upstream and a broad range of services of different technological intensity, involving regional and local factors in different cities, according to their location, functions, regional historical trajectory and localities, and its potential for integration and economic diversification. In such a system of organization, Neuquén capital is a center provider public and private, social, personal and business, of varying degrees of complexity and scope regional services. It bases the larger companies are based. Other cities operate as centers of medium importance and attract small and medium-sized firms; and a set of smaller

  19. Apparatus and methods for hydrocarbon extraction

    Science.gov (United States)

    Bohnert, George W.; Verhulst, Galen G.

    2016-04-26

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  20. Hydrocarbon-stapled lipopeptides exhibit selective antimicrobial activity.

    Science.gov (United States)

    Jenner, Zachary B; Crittenden, Christopher M; Gonzalez, Martín; Brodbelt, Jennifer S; Bruns, Kerry A

    2017-01-10

    Antimicrobial peptides (AMPs) occur widely in nature and have been studied for their therapeutic potential. AMPs are of interest due to the large number of possible chemical structural combinations using natural and unnatural amino acids, with varying effects on their biological activities. Using physicochemical properties from known naturally occurring amphipathic cationic AMPs, several hydrocarbon-stapled lipopeptides (HSLPs) were designed, synthesized, and tested for antimicrobial properties. Peptides were chemically modified by N-terminal acylation, C-terminal amidation, and some were hydrocarbon stapled by intramolecular olefin metathesis. The effects of peptide length, amphipathic character, and stapling on antimicrobial activity were tested against Escherichia coli, three species of Gram-positive bacteria (Staphylococcus aureus, Bacillus megaterium, and Enterococcus faecalis), and two strains of Candida albicans. Peptides were shown to disrupt liposomes of different phospholipid composition, as measured by leakage of a fluorescent compound from vesicles. Peptides with (S)-2-(4'-pentenyl)-alanine substituted for L-alanine in a reference peptide showed a marked increase in antimicrobial activity, hemolysis, and membrane disruption. Stapled peptides exhibited slightly higher antimicrobial potency; those with greatest hydrophobic character showed the greatest hemolysis and liposome leakage, but lower antimicrobial activity. The results support a model of HSLPs as membrane-disruptive AMPs with potent antimicrobial activity and relatively low hemolytic potential at biologically active peptide concentrations. This article is protected by copyright. All rights reserved.

  1. Structural Evolution of Interstellar Polycyclic Aromatic Hydrocarbons

    Science.gov (United States)

    Hammonds, Mark; Candian, Alessandra; Mori, Tamami; Usui, Fumihiko; Onaka, Takashi

    2015-08-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are an important reservoir for molecular carbon in the interstellar medium (ISM), and investigations into their chemistry and behaviour may be important to the understanding of how carbon is processed from simple forms into complex prebiotic molecules such as those detected in chondritic meteorites. In this study, infrared astronomical data from AKARI and other observatories are used together with laboratory and theoretical data to study variations in the structure of emitting PAHs in interstellar environments using spectroscopic decomposition techniques and bands arising from carbon-hydrogen bond vibrations at wavelengths from 3 - 14 microns. Results and inferences are discussed in terms of the processing of large carbonaceous molecules in astrophysical environments.

  2. Microbial hydrocarbons: back to the future

    Energy Technology Data Exchange (ETDEWEB)

    Work, Victoria H.; Beliaev, Alex S.; Konopka, Allan; Posewitz, Matthew C.

    2012-03-01

    The defining challenge of energy research in the 21st century is the development and deployment of technologies for large-scale reconfiguration of global energy infrastructure. Modern society is built upon a concentrated yet finite reservoir of diverse hydrocarbons formed through the photosynthetic transformation of several hundred million years of solar energy. In human history, the fossil energy era will be short lived and never repeated. Although the timing of peak oil is extensively debated, it is an eventuality. It is, therefore, imperative that projections for both when it will occur and the degree to which supply will fall short of demand be taken into serious consideration, especially in the sectors of energy technology development, political and economic decision making, and societal energy usage. The requirement for renewable energy systems is no longer a point for discussion, and swift advances on many fronts are vital to counteract current and impending crises in both energy and the environment.

  3. Transanal stent in anterior resection does not prevent anastomotic leakage

    DEFF Research Database (Denmark)

    Bülow, Steffen; Bulut, O; Christensen, Ib Jarle;

    2006-01-01

    OBJECTIVE: A defunctioning transanal stent may theoretically reduce the leakage rate after anterior rectal resection. We present a randomized open study with the aim of comparing the leakage rate after anterior resection with a loop ileostomy, a transanal stent, both or neither. PATIENTS...... completion of the operation the patients were randomized in two groups with and without a transanal stent. RESULTS: A clinically significant leakage was diagnosed in 25 patients (13%). No significant difference was found 17 of 98 patients with a stent and 8 of 96 without (P = 0.09), or in 9 of 44 ileostomy...... patients with a stent and in 3 of 45 without (P = 0.07). Several leaks over a short time led to an interim analysis after inclusion of 194 of 448 planned patients. The analysis showed no significant protective effect of the stent, and more leakages in the stent group, although not statistically significant...

  4. Natural and industrial analogues for leakage of CO2 from storagereservoirs: identification of features, events, and processes and lessonslearned

    Energy Technology Data Exchange (ETDEWEB)

    Lewicki, Jennifer L.; Birkholzer, Jens; Tsang, Chin-Fu

    2006-02-28

    for CO2 flow from depth to the surface. Risk assessment shouldtherefore emphasize determining the potential for and nature of CO2migration along these structures. Fourth, wells that are structurallyunsound have the potential to rapidly release large quantities of CO2 tothe atmosphere. Risk assessment should therefore be focused on thepotential for both active and abandoned wells at storage sites totransport CO2 to the surface, particularly at sites with depleted oil orgas reservoirs where wellsare abundant. Fifth, the style of CO2 releaseat the surface varies widely between and within different leakage sites.In rare circumstances, the release of CO2 can be a self-enhancing and/oreruptive process; this possibility should be assessed in the case of CO2leakage from storage reservoirs. Sixth, the hazard to human health hasbeen small in most cases of large surface releases of CO2. This could bedue to implementation of public education and CO2 monitoring programs;these programs should therefore be employed to minimize potential health,safety, and environmental effects associated with CO2 leakage. Finally,while changes in groundwater chemistry were related to CO2 leakage due toacidification and interaction with host rocks along flow paths, watersremained potable in most cases. Groundwaters should be monitored forchanges that may be associated with storage reservoirleakage.

  5. Reservoir geochemistry: A link between reservoir geology and engineering?

    Energy Technology Data Exchange (ETDEWEB)

    Larter, S.R.; Aplin, A.C. [Univ. of Newcastle upon Tyne (United Kingdom); Corbett, P.; Ementon, N. [Heriot-Watt Univ., Edinburgh (United Kingdom)

    1994-12-31

    Geochemistry provides a natural but poorly exploited link between reservoir geology and engineering. The authors summarize some current applications of geochemistry to reservoir description and stress that because of their strong interactions with mineral surfaces and water, nitrogen and oxygen compounds in petroleum may exert an important influence on the PVT properties of petroleum, viscosity and wettability. The distribution of these compounds in reservoirs is heterogeneous on a sub-meter scale and is partly controlled by variations in reservoir quality. The implied variations in petroleum properties and wettability may account for some of the errors in reservoir simulations.

  6. Reservoir geochemistry: A link between reservoir geology and engineering?

    Energy Technology Data Exchange (ETDEWEB)

    Larter, S.R.; Aplin, A.C.; Chen, M.; Taylor, P.N. [Univ. of Newcastle (Australia); Corbett, P.W.M.; Ementon, N. [Heriot-Watt Univ., Edinburgh (United Kingdom)

    1997-02-01

    Geochemistry provides a natural, but poorly exploited, link between reservoir geology and engineering. The authors summarize some current applications of geochemistry to reservoir description and stress that, because of their strong interactions with mineral surfaces and water, nitrogen and oxygen compounds in petroleum may exert an important influence on the pressure/volume/temperature (PVT) properties of petroleum, viscosity and wettability. The distribution of these compounds in reservoirs is heterogeneous on a submeter scale and is partly controlled by variations in reservoir quality. The implied variations in petroleum properties and wettability may account for some of the errors in reservoir simulations.

  7. Mantle hydrocarbons: abiotic or biotic?

    Science.gov (United States)

    Sugisaki, R; Mimura, K

    1994-06-01

    Analyses of 227 rocks from fifty localities throughout the world showed that mantle derived rocks such as tectonized peridotites in ophiolite sequences (tectonites) arid peridotite xenoliths in alkali basalts contain heavier hydrocarbons (n-alkanes), whereas igneous rocks produced by magmas such as gabbro arid granite lack them. The occurrence of hydrocarbons indicates that they were not derived either from laboratory contamination or from held contamination; these compounds found in the mantle-derived rocks are called here "mantle hydrocarbons." The existence of hydrocarbons correlates with petrogenesis. For example, peridotite cumulates produced by magmatic differentiation lack hydrocarbons whereas peridotite xenoliths derived from the mantle contain them. Gas chromatographic-mass spectrometric records of the mantle hydrocarbons resemble those of aliphatics in meteorites and in petroleum. Features of the hydrocarbons are that (a) the mantle hydrocarbons reside mainly along grain boundaries and in fluid inclusions of minerals; (b) heavier isoprenoids such as pristane and phytane are present; and (c) delta 13C of the mantle hydrocarbons is uniform (about -27%). Possible origins for the mantle hydrocarbons are as follows. (1) They were in organically synthesized by Fischer-Tropsch type reaction in the mantle. (2) They were delivered by meteorites and comets to the early Earth. (3) They were recycled by subduction. The mantle hydrocarbons in the cases of (1) and (2) are abiogenic and those in (3) are mainly biogenic. It appears that hydrocarbons may survive high pressures and temperatures in the mantle, but they are decomposed into lighter hydrocarbon gases such as CH4 at lower pressures when magmas intrude into the crust; consequently, peridotite cumulates do not contain heavier hydrocarbons but possess hydrocarbon gases up to C4H10.

  8. On the feasibility of inducing oil mobilization in existing reservoirs via wellbore harmonic fluid action

    KAUST Repository

    Jeong, Chanseok

    2011-03-01

    Although vibration-based mobilization of oil remaining in mature reservoirs is a promising low-cost method of enhanced oil recovery (EOR), research on its applicability at the reservoir scale is still at an early stage. In this paper, we use simplified models to study the potential for oil mobilization in homogeneous and fractured reservoirs, when harmonically oscillating fluids are injected/produced within a well. To this end, we investigate first whether waves, induced by fluid pressure oscillations at the well site, and propagating radially and away from the source in a homogeneous reservoir, could lead to oil droplet mobilization in the reservoir pore-space. We discuss both the fluid pore-pressure wave and the matrix elastic wave cases, as potential agents for increasing oil mobility. We then discuss the more realistic case of a fractured reservoir, where we study the fluid pore-pressure wave motion, while taking into account the leakage effect on the fracture wall. Numerical results show that, in homogeneous reservoirs, the rock-stress wave is a better energy-delivery agent than the fluid pore-pressure wave. However, neither the rock-stress wave nor the pore-pressure wave is likely to result in any significant residual oil mobilization at the reservoir scale. On the other hand, enhanced oil production from the fractured reservoir\\'s matrix zone, induced by cross-flow vibrations, appears to be feasible. In the fractured reservoir, the fluid pore-pressure wave is only weakly attenuated through the fractures, and thus could induce fluid exchange between the rock formation and the fracture space. The vibration-induced cross-flow is likely to improve the imbibition of water into the matrix zone and the expulsion of oil from it. © 2011 Elsevier B.V.

  9. Comparative analysis of metagenomes from three methanogenic hydrocarbon-degrading enrichment cultures with 41 environmental samples

    Science.gov (United States)

    Tan, Boonfei; Jane Fowler, S; Laban, Nidal Abu; Dong, Xiaoli; Sensen, Christoph W; Foght, Julia; Gieg, Lisa M

    2015-01-01

    Methanogenic hydrocarbon metabolism is a key process in subsurface oil reservoirs and hydrocarbon-contaminated environments and thus warrants greater understanding to improve current technologies for fossil fuel extraction and bioremediation. In this study, three hydrocarbon-degrading methanogenic cultures established from two geographically distinct environments and incubated with different hydrocarbon substrates (added as single hydrocarbons or as mixtures) were subjected to metagenomic and 16S rRNA gene pyrosequencing to test whether these differences affect the genetic potential and composition of the communities. Enrichment of different putative hydrocarbon-degrading bacteria in each culture appeared to be substrate dependent, though all cultures contained both acetate- and H2-utilizing methanogens. Despite differing hydrocarbon substrates and inoculum sources, all three cultures harbored genes for hydrocarbon activation by fumarate addition (bssA, assA, nmsA) and carboxylation (abcA, ancA), along with those for associated downstream pathways (bbs, bcr, bam), though the cultures incubated with hydrocarbon mixtures contained a broader diversity of fumarate addition genes. A comparative metagenomic analysis of the three cultures showed that they were functionally redundant despite their enrichment backgrounds, sharing multiple features associated with syntrophic hydrocarbon conversion to methane. In addition, a comparative analysis of the culture metagenomes with those of 41 environmental samples (containing varying proportions of methanogens) showed that the three cultures were functionally most similar to each other but distinct from other environments, including hydrocarbon-impacted environments (for example, oil sands tailings ponds and oil-affected marine sediments). This study provides a basis for understanding key functions and environmental selection in methanogenic hydrocarbon-associated communities. PMID:25734684

  10. Comparative analysis of metagenomes from three methanogenic hydrocarbon-degrading enrichment cultures with 41 environmental samples.

    Science.gov (United States)

    Tan, Boonfei; Fowler, S Jane; Abu Laban, Nidal; Dong, Xiaoli; Sensen, Christoph W; Foght, Julia; Gieg, Lisa M

    2015-09-01

    Methanogenic hydrocarbon metabolism is a key process in subsurface oil reservoirs and hydrocarbon-contaminated environments and thus warrants greater understanding to improve current technologies for fossil fuel extraction and bioremediation. In this study, three hydrocarbon-degrading methanogenic cultures established from two geographically distinct environments and incubated with different hydrocarbon substrates (added as single hydrocarbons or as mixtures) were subjected to metagenomic and 16S rRNA gene pyrosequencing to test whether these differences affect the genetic potential and composition of the communities. Enrichment of different putative hydrocarbon-degrading bacteria in each culture appeared to be substrate dependent, though all cultures contained both acetate- and H2-utilizing methanogens. Despite differing hydrocarbon substrates and inoculum sources, all three cultures harbored genes for hydrocarbon activation by fumarate addition (bssA, assA, nmsA) and carboxylation (abcA, ancA), along with those for associated downstream pathways (bbs, bcr, bam), though the cultures incubated with hydrocarbon mixtures contained a broader diversity of fumarate addition genes. A comparative metagenomic analysis of the three cultures showed that they were functionally redundant despite their enrichment backgrounds, sharing multiple features associated with syntrophic hydrocarbon conversion to methane. In addition, a comparative analysis of the culture metagenomes with those of 41 environmental samples (containing varying proportions of methanogens) showed that the three cultures were functionally most similar to each other but distinct from other environments, including hydrocarbon-impacted environments (for example, oil sands tailings ponds and oil-affected marine sediments). This study provides a basis for understanding key functions and environmental selection in methanogenic hydrocarbon-associated communities.

  11. Reservoir description of Endicott Field, Prudhoe Bay, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Behrman, P.G.; Woidneck, R.K.; Soule, C.H.; Wu, J.L.

    1985-04-01

    Located about 2 mi offshore and several miles east of Prudhoe Bay, the Endicott field contains about 1.4 billion reservoir bbl of oil and 0.5 billion reservoir bbl of gas. Hydrocarbons occur within Mississippian fluvial sandstones of the Kekiktuk formation, which unconformably overlies the Neruokpuk Formation and grades upward into the Kayak and Itkilyariak formations. Stratigraphy is subdivided into three lithofacies that, from the base upward, reflect deposition in a swamp/lacustrine/flood plain environment (zone I), a braided stream system (zone 2), and a meandering stream system (zone 3). Sediment dispersal was from a northerly source. Endicott field structure defines a southwesterly plunging antiform that is bounded to the north, northeast, and southwest by major normal faults and is truncated to the northeast by the Lower Cretaceous Unconformity (LCU). Shales overlying the LCU and shales of the Kayak and Itkilyariak formations from the reservoir cap. Reservoir properties with the hydrocarbon column vary by zone with zones 3 and 2 typified by an average net/gross-porosity-water saturation-permeability of 37%-18%-22%-500 md and 88%-22%-13%-1100 md, respectively. In contrast, zone 1 quality is very poor. Reservoir sands are compositionally very mature and exhibit an enhanced pore network. Diagenetic minerals include quartz along with lesser kaolinite and carbonate. Gas is present from about 9500 ft (2850 m) to 9855 ft (2958 m), oil is down to 10,180-10,200 ft (3054-3060 m), and tar accumulations are down to 10,400 ft (3120 m) subsea. Average oil gravity is 23/sup 0/ API. Geochemical data indicate that the tar accumulations originated through a physical deasphaltine process. Cenozoic imbibition resulted in water overriding tar.

  12. Reducing the leakage of body-worn incontinence pads.

    Science.gov (United States)

    Clancy, B; Malone-Lee, J

    1991-02-01

    The aim of this research was to evaluate the effect of various absorbent materials (fluff pulp and superabsorbent) on the leakage performance of incontinence pads. A shaped pad-and-pant system was used as the basic design and four pad types made to different specifications were compared using a double-blind technique. Forty-five elderly hospital residents who were incontinent of urine used all four pad types in a randomly allocated order. Data were recorded on more than 5000 pads over a 2-month period. Leakage was reduced by adding a second layer of fluff pulp and, whilst the addition of a superabsorbent material tended to reduce leakage further, we found no clear relationship between the amount of superabsorbent and the reduction of leakage. Other data indicated the importance of securing the pad in place with the appropriate net pants and the leakage rates of pads in relation to the amount of urine they contained. This research suggests that superabsorbent materials have great potential for reducing the leakage rate of incontinence pads but that the way in which they are incorporated into the pad, the amount of fluff pulp and the design of the pad also play an important part.

  13. Development of a new duct leakage test: DeltaQ

    Energy Technology Data Exchange (ETDEWEB)

    Walker,I.S.; Sherman,M.H.; Wempen, J.; Wang, D.; McWilliams, J.A.; Dickerhoff, D.J.

    2001-08-01

    Duct leakage is a key factor in determining energy losses from forced air heating and cooling systems. Several studies (Francisco and Palmiter 1997 and 1999, Andrews et al. 1998, and Siegel et al. 2001) have shown that the duct system efficiency cannot be reliably determined without good estimates of duct leakage. Specifically, for energy calculations, it is the duct leakage air flow to outside at operating conditions that is required. Existing test methods either precisely measure the size of leaks (but not the flow through them at operating conditions), or measure these flows with insufficient accuracy. The DeltaQ duct leakage test method was developed to provide improved estimates of duct leakage during system operation. In this study we developed the analytical calculation methods and the test procedures used in the DeltaQ test. As part of the development process, we have estimated uncertainties in the test method (both analytically and based on field data) and designed automated test procedures to increase accuracy and reduce the contributions of operator errors in performing field tests. In addition, the test has been evaluated in over 100 houses by several research teams to show that it can be used in a wide range of houses and to aid in finding limits or problems in field applications. The test procedure is currently being considered by ASTM as an update of an existing duct leakage standard.

  14. Leakage Power Reduction and Analysis of CMOS Sequential Circuits

    Directory of Open Access Journals (Sweden)

    M. Janaki Rani

    2012-02-01

    Full Text Available A significant portion of the total power consumption in high performance digital circuits in deep sub micron regime is mainly due to leakage power. Leakage is the only source of power consumption in an idle circuit. Therefore it is important to reduce leakage power in portable systems. In this paper two techniques such as transistor stacking and self-adjustable voltage level circuit for reducing leakage power in sequential circuits are proposed. This work analyses the power and delay of three different types of D flip-flops using pass transistors, transmission gates and gate diffusion input gates. . All the circuits are simulated with and without the application of leakage reduction techniques. Simulation results show that the proposed pass transistor based D flip-flop using self-adjustable voltage level circuit has the least leakage power dissipation of 9.13nW with a delay of 77 nS. The circuits are simulated with MOSFET models of level 54 using HSPICE in 90 nm process technology.

  15. Bacterial sources for phenylalkane hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, L.; Winans, R.E. [Argonne National Lab., IL (United States); Langworthy, T. [Univ. of South Dakota, Vermillion, SD (United States)

    1996-10-01

    The presence of phenylalkane hydrocarbons in geochemical samples has been the source of much controversy. Although an anthropogenic input from detergent sources always appears likely, the distribution of phenylalkane hydrocarbons in some cases far exceeding that attributed to detergent input has led to a reappraisal of this view. Indeed, recent work involving analysis of the lipid hydrocarbon extracts from extant Thermoplasma bacteria has revealed the presence of phenylalkane hydrocarbons. The presence of phenylalkane hydrocarbons in sedimentary organic matter may therefore represent potential biological markers for thermophilic bacteria.

  16. Copper Ion as a New Leakage Tracer

    Directory of Open Access Journals (Sweden)

    Modaresi J.

    2013-12-01

    Full Text Available Statement of Problem: Most failures of root canal treatments are caused by bacteria. Studies showed that the most common cause of endodontic failures were the incomplete obturation of the root canal and the lack of adequate apical seal. Some in-vitro methods are used to estimate sealing quality, generally by measuring microleakage that allows the tracer agent to penetrate the filled canal.Purpose: Conventional methods of evaluating the seal of endodontically treated teeth are complicated and have some drawbacks. We used copper ion diffusion method to assess the leakage and the results were compared to dye penetration method.Materials and Method: The crowns of 21 extracted teeth were cut off at the CEJ level. After preparing the canals, the teeth were placed in tubes containing saline. They were divided randomly into 15 experimental cases; 3 positive and 3 negative controls. Positive controls were filled by single cone without sealer while the experimental and the negative control groups were filled by lateral technique. The coronal portion of gutta was removed and 9mm was left. The external surface of each tooth was coated with nail polish. Two millimeters of apical portion was immersed into 9ml of distilled water and 0.3ml of CuSO4 solution was injected into the coronal portion. After 2 days, copper sulfate was measured by an atomic absorption spectrophotometer. The teeth were then immersed in 2% methylene blue for 24 hours, sectioned and the extent of dye penetration was measured by a stereomicroscope.Results: The maximum and minimum recorded copper ion concentrations for the experimental group were 18.37 and 2.87ppm respectively. The maximum and minimum recorded dye penetrations for the experimental group were 8.5 and 3.5mm respectively. The statistical analysis, adopting paired samples test, showed poor correlation between average recorded results of two methods.Conclusion: Based on our results, there was no significant correlation between

  17. Fluid typing and tortuosity analysis with NMR-DE techniques in volcaniclastic reservoirs, Patagonia/Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Bustos, Ulises Daniel [Schlumberger Argentina S.A., Buenos Aires (Argentina); Breda, Eduardo Walter [Repsol YPF Comodoro Rivadavia, Chubut (Argentina)

    2004-07-01

    Alternative hydrocarbon-detection techniques are used to differentiate water from hydrocarbon where resistivity-based methods are difficult to apply, such as freshwater reservoirs and complex lithologies. One of these areas is represented by the complex volcaniclastic freshwater reservoirs in the Golfo San Jorge basin, Patagonia Argentina, where water and oil have often identical response on conventional logs. Some advances in hydrocarbon identification based on nuclear magnetic resonance (NMR) techniques were achieved in long T1 environments (very light oils, gas) in the Golfo San Jorge basin by previous NMR fluid typing methods. However, since medium to heavy oils are commonly present in these intervals, hydrocarbon detection by such techniques cannot be properly achieved. In addition, restricted diffusion phenomena recognized in these intervals, constitute further complications in fluid typing since its presence have similar response than native oil. To address this problem, a fluid characterization method using NMR Diffusion-Editing techniques and processing/interpretation with D-T2 maps in a suite of NMR measurements was applied. The technique allowed the detection and evaluation of restricted diffusion in these reservoirs, enabling better hydrocarbon characterization in a broad viscosity range (from light to heavy). The method also improved the petrophysical evaluation because restricted diffusion is related to tortuosity in the reservoir. Since the application of this innovative reservoir evaluation method, fluid prognosis vs well completion results was increased from around 68% to around 88% in Golfo San Jorge basin. Moreover, in some of these areas rates above 95% were recently achieved in 2004. (author)

  18. Coupling of Multiphase Flow and Geomechanics in Fractured Porous Media: Application to CO2 Leakages from Natural and Stimulated Fractures

    Science.gov (United States)

    Ezzedine, S. M.

    2015-12-01

    Leakage to the atmosphere of a significant fraction of injected CO2 would constitute a failure of a geological CO2 storage project from a greenhouse gas mitigation perspective. We present a numerical model that simulates flow and transport of CO2 into heterogeneous subsurface systems. The model, StoTran, is a flexible numerical environment that uses state-of-the-art finite element and finite volume methods and unstructured adaptive mesh refinement scheme implemented using MPI and OpenMP protocols. Multiphase flow equations and the geomechanical equations are implicitly solved and either fully or sequentially coupled. StoTran can address inverse and forward problems under deterministic or stochastic conditions. For the current study, StoTran has been used to simulate several scenarios spanning from a homogeneous single layered reservoir to heterogeneous multi-layered systems, which including cap-rock with embedded fractures, have been simulated under different operations of CO2 injection and CO2 leakages conditions. Results show the impact of the injection and leakage rates on the time evolution of the spread of the CO2 plume, its interception of the fractured cap-rock and the risk associated with the contamination of the overlaying aquifer. Spatial and temporal moments have been calculated for different, deterministic of stochastic, subsurface physical and chemical properties. Spatial moments enable assessing the extent of the region of investigation under conditions of uncertainty. Furthermore, several leakage scenarios show the intermittence behavior and development of the CO2 plume in the subsurface; its first interception with the fractures located further far from the injection well then, at a second stage, its interception with the fracture within the immediate vicinity of the injection well. We will present a remedy to CO2 leakages from the reservoir in order to enhance a long term containment of the injected CO2. This work performed under the auspices of

  19. Synergizing Crosswell Seismic and Electromagnetic Techniques for Enhancing Reservoir Characterization

    KAUST Repository

    Katterbauer, Klemens

    2015-11-18

    Increasing complexity of hydrocarbon projects and the request for higher recovery rates have driven the oil-and-gas industry to look for a more-detailed understanding of the subsurface formation to optimize recovery of oil and profitability. Despite the significant successes of geophysical techniques in determining changes within the reservoir, the benefits from individually mapping the information are limited. Although seismic techniques have been the main approach for imaging the subsurface, the weak density contrast between water and oil has made electromagnetic (EM) technology an attractive complement to improve fluid distinction, especially for high-saline water. This crosswell technology assumes greater importance for obtaining higher-resolution images of the interwell regions to more accurately characterize the reservoir and track fluid-front developments. In this study, an ensemble-Kalman-based history-matching framework is proposed for directly incorporating crosswell time-lapse seismic and EM data into the history-matching process. The direct incorporation of the time-lapse seismic and EM data into the history-matching process exploits the complementarity of these data to enhance subsurface characterization, to incorporate interwell information, and to avoid biases that may be incurred from separate inversions of the geophysical data for attributes. An extensive analysis with 2D and realistic 3D reservoirs illustrates the robustness and enhanced forecastability of critical reservoir variables. The 2D reservoir provides a better understanding of the connection between fluid discrimination and enhanced history matches, and the 3D reservoir demonstrates its applicability to a realistic reservoir. History-matching enhancements (in terms of reduction in the history-matching error) when incorporating both seismic and EM data averaged approximately 50% for the 2D case, and approximately 30% for the 3D case, and permeability estimates were approximately 25

  20. Microbial degradation of petroleum hydrocarbons.

    Science.gov (United States)

    Varjani, Sunita J

    2017-01-01

    Petroleum hydrocarbon pollutants are recalcitrant compounds and are classified as priority pollutants. Cleaning up of these pollutants from environment is a real world problem. Bioremediation has become a major method employed in restoration of petroleum hydrocarbon polluted environments that makes use of natural microbial biodegradation activity. Petroleum hydrocarbons utilizing microorganisms are ubiquitously distributed in environment. They naturally biodegrade pollutants and thereby remove them from the environment. Removal of petroleum hydrocarbon pollutants from environment by applying oleophilic microorganisms (individual isolate/consortium of microorganisms) is ecofriendly and economic. Microbial biodegradation of petroleum hydrocarbon pollutants employs the enzyme catalytic activities of microorganisms to enhance the rate of pollutants degradation. This article provides an overview about bioremediation for petroleum hydrocarbon pollutants. It also includes explanation about hydrocarbon metabolism in microorganisms with a special focus on new insights obtained during past couple of years. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. New insights into late Neogene glacial dynamics, tectonics, and hydrocarbon migrations in the Atlantic-Arctic gateway region.

    Science.gov (United States)

    Knies, J.; Baranwal, S.; Fabian, K.; Grøsfjeld, K.; Andreassen, K.; Husum, K.; Mattingsdal, R.; Gaina, C.; De Schepper, S.; Vogt, C.; Andersen, N.

    2012-04-01

    Notwithstanding the recent IODP drilling on the Lomonosov Ridge, the Late Cenozoic history of the Arctic Ocean still remains elusive. The tectonic processes leading to the development of the only deep-water connection to the Arctic Ocean via the Fram Strait are still poorly understood. Also, the influence of the gateway region on changes in Arctic-Atlantic ocean circulation, uplift/erosion on the adjacent hinterland, as well as glacial initiation and its consequences for the petroleum systems in the regions, remain unclear. By revisiting Ocean Drilling Program (ODP) Leg 151, holes 911A and 910C and interpreting new multi-channel seismic data, we have now established a new comprehensive chronological framework for the Yermak Plateau and revealed important paleoenvironmental changes for the Atlantic-Arctic gateway during the late Neogene. The improved chronostratigraphic framework is established through continuous paleomagnetic and biostratigraphic data as well as selected intervals with stable ?18O and ?13C data derived from benthic foraminifera Cassidulina teretis. Supported by acoustic profiling, the new data indicate a continuous late Miocene/early Pliocene age (~5-6 Ma) for the base of both holes. The depositional regime north (Yermak Plateau) and south of the Fram Strait (Hovgaard Ridge) was rather shallow during the late Miocene and water mass exchange between the Arctic and Atlantic was restricted. Ice sheets on the Svalbard Platform evolved during the late Miocene, however did not reach the coastline before 3.3 Ma. Migration of gaseous hydrocarbons occurred prior to the intensification of the Northern Hemisphere Glaciations (~2.7 Ma) as indicated by high-amplitude reflections, corroborating the occurrence of greigite mineralization and stable carbon isotope excursions in planktic/benthic foraminifera. The data indicate that Pleistocene erosion and uplift in the Barents Sea region had probably only minor effects on reservoir leakages than previously thought.

  2. Superconductivity in aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Kubozono, Yoshihiro, E-mail: kubozono@cc.okayama-u.ac.jp [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Research Center of New Functional Materials for Energy Production, Storage and Transport, Okayama University, Okayama 700-8530 (Japan); Japan Science and Technology Agency, ACT-C, Kawaguchi 332-0012 (Japan); Goto, Hidenori; Jabuchi, Taihei [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Yokoya, Takayoshi [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Research Center of New Functional Materials for Energy Production, Storage and Transport, Okayama University, Okayama 700-8530 (Japan); Kambe, Takashi [Department of Physics, Okayama University, Okayama 700-8530 (Japan); Sakai, Yusuke; Izumi, Masanari; Zheng, Lu; Hamao, Shino; Nguyen, Huyen L.T. [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Sakata, Masafumi; Kagayama, Tomoko; Shimizu, Katsuya [Center of Science and Technology under Extreme Conditions, Osaka University, Osaka 560-8531 (Japan)

    2015-07-15

    Highlights: • Aromatic superconductor is one of core research subjects in superconductivity. Superconductivity is observed in certain metal-doped aromatic hydrocarbons. Some serious problems to be solved exist for future advancement of the research. This article shows the present status of aromatic superconductors. - Abstract: ‘Aromatic hydrocarbon’ implies an organic molecule that satisfies the (4n + 2) π-electron rule and consists of benzene rings. Doping solid aromatic hydrocarbons with metals provides the superconductivity. The first discovery of such superconductivity was made for K-doped picene (K{sub x}picene, five benzene rings). Its superconducting transition temperatures (T{sub c}’s) were 7 and 18 K. Recently, we found a new superconducting K{sub x}picene phase with a T{sub c} as high as 14 K, so we now know that K{sub x}picene possesses multiple superconducting phases. Besides K{sub x}picene, we discovered new superconductors such as Rb{sub x}picene and Ca{sub x}picene. A most serious problem is that the shielding fraction is ⩽15% for K{sub x}picene and Rb{sub x}picene, and it is often ∼1% for other superconductors. Such low shielding fractions have made it difficult to determine the crystal structures of superconducting phases. Nevertheless, many research groups have expended a great deal of effort to make high quality hydrocarbon superconductors in the five years since the discovery of hydrocarbon superconductivity. At the present stage, superconductivity is observed in certain metal-doped aromatic hydrocarbons (picene, phenanthrene and dibenzopentacene), but the shielding fraction remains stubbornly low. The highest priority research area is to prepare aromatic superconductors with a high superconducting volume-fraction. Despite these difficulties, aromatic superconductivity is still a core research target and presents interesting and potentially breakthrough challenges, such as the positive pressure dependence of T{sub c} that is clearly

  3. Mechanisms of abnormal overpressure generation in Kuqa foreland thrust belt and their impacts on oil and gas reservoir formation

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Based on overview for mechanism of abnormal overpressure generation in sedimentary basins, an insight discussion is made by the authors for the distribution, features and generation mechanisms of abnormal overpressure in the Kuqa foreland thrust belt. The abnormal overpressure in the Kelasu structure zone west to the Kuqa foreland thrust belt was primarily distributed in Eogene to lower Cretaceous formations; structural compression and structural emplacement as well as the containment of Eogene gyps-salt formation constituted the main mechanisms for the generation of abnormal overpressure. The abnormal overpressure zone in the eastern Yiqikelike structure zone was distributed primarily in lower Jurassic Ahe Group, resulting from hydrocarbon generation as well as structural stress other than from under-compaction. Various distributions and generating mechanisms have different impacts upon the formation of oil and gas reservoirs. K-E reservoir in the Kelasu zone is an allochthonous abnormal overpressure system. One of the conditions for reservoir accumulation is the migration of hydrocarbon (T-J hydrocarbon source rock) along the fault up to K-E reservoir and accumulated into reservoir. And this migration process was controlled by the abnormal overpressure system in K-E reservoir. The confined abnormal overpressure system in the Yiqikelike structure zone constituted the main cause for the poor developing of dissolved porosity in T-J reservoir, resulting in poor physical property of reservoir. The poor physical property of T-J reservoir of Yinan 2 structure was the main cause for the absence of oil accumulation, but the presence of natural gas reservoir in the structure.

  4. Status of Blue Ridge Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-09-01

    This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Blue Ridge Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports and data available, as well as interview with water resource professionals in various federal, state, and local agencies. Blue Ridge Reservoir is a single-purpose hydropower generating project. When consistent with this primary objective, the reservoir is also operated to benefit secondary objectives including water quality, recreation, fish and aquatic habitat, development of shoreline, aesthetic quality, and other public and private uses that support overall regional economic growth and development. 8 refs., 1 fig.

  5. Exploration Potential of Marine Source Rocks Oil-Gas Reservoirs in China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    So far, more than 150 marine oil-gas fields have been found onshore and offshore about 350.The marine source rocks are mainly Paleozoic and Mesozoic onshore whereas Tertiary offshore. Three genetic categories of oil-gas reservoirs have been defined for the marine reservoirs in China: primary reservoirs, secondary reservoirs and hydrocarbon-regeneration reservoirs. And three exploration prospects have also been suggested: (1) Primary reservoirs prospects, which are chiefly distributed in many Tertiary basins of the South China Sea (SCS), the Tertiary shelf basins of the East China Sea (ECS) and the Paleozoic of Tarim basin, Sichuan basin and Ordos basin. To explore large-middle-scale even giant oil-gas fields should chiefly be considered in this category reservoirs. These basins are the most hopeful areas to explore marine oil-gas fields in China, among which especially many Tertiary basins of the SCS should be strengthened to explore. (2) Secondary reservoirs prospects, which are mainly distributed in the Paleozoic and Mesozoic of the Tarim basin, Sichuan basin, Qiangtang basin and Chuxiong basin in western China, of which exploration potential is less than that of the primary reservoirs. (3) Hydrocarbon-regeneration reservoirs prospects, which are chiefly distributed in the Bohai Bay basin, North Jiangsu-South Yellow Sea basin, southern North China basin, Jianghan basin,South Poyang basin in eastern China and the Tarim basin in western China, of which source rocks are generally the Paleozoic. And the reservoirs formed by late-stage (always Cenozoic) secondary hydrocarbon generation of the Paleozoic source rocks should mainly be considered to explore, among which middle-small and small oil-gas fields are the chief exploration targets. As a result of higher thermal evolution of Paleozoic and Mesozoic source rocks, the marine reservoirs onshore are mainly gas fields, and so far marine oil fields have only been found in the Tarim basin. No other than establishing

  6. Squared exponential covariance function for prediction of hydrocarbon in seabed logging application

    Science.gov (United States)

    Mukhtar, Siti Mariam; Daud, Hanita; Dass, Sarat Chandra

    2016-11-01

    Seabed Logging technology (SBL) has progressively emerged as one of the demanding technologies in Exploration and Production (E&P) industry. Hydrocarbon prediction in deep water areas is crucial task for a driller in any oil and gas company as drilling cost is very expensive. Simulation data generated by Computer Software Technology (CST) is used to predict the presence of hydrocarbon where the models replicate real SBL environment. These models indicate that the hydrocarbon filled reservoirs are more resistive than surrounding water filled sediments. Then, as hydrocarbon depth is increased, it is more challenging to differentiate data with and without hydrocarbon. MATLAB is used for data extractions for curve fitting process using Gaussian process (GP). GP can be classified into regression and classification problems, where this work only focuses on Gaussian process regression (GPR) problem. Most popular choice to supervise GPR is squared exponential (SE), as it provides stability and probabilistic prediction in huge amounts of data. Hence, SE is used to predict the presence or absence of hydrocarbon in the reservoir from the data generated.

  7. Multi-technique monitoring of CO2 leakage from an engineered CO2 leakage experiment

    Science.gov (United States)

    Zhou, X.; Apple, M. E.; Dobeck, L.; Cunningham, A. B.; Spangler, L.

    2012-12-01

    Monitoring of canopy and soil geophysical and geochemical properties in vadose zone by multiple techniques were carried out from 1999 to 2012 using an engineered CO2 release to simulate the CO2 leakage from CO2 storage at an agricultural plot at Bozeman, MT. The CO2 release was based on a horizontally-drilled well of 100 m at a depth of about 2.0-2.3m (Fig.1). Techniques utilized include hyperspectral and infrared radiation of various vegetations, electric conductivity in soil, magnetic field at the ground surface, and soil gas composition and dynamics using various gas sensors and soil moisture sensors. Measurements were made at several sites along a transect perpendicular to the releasing well, along which the soil CO2 concentration attenuated from high to normal condition at control site. The response of the canopy hyperspectral reflectance, infrared radiation, soil geophysical properties such as soil electric conductivity, top soil magnetic susceptibility and magnetic field, soil gas composition such as CO2 and O2 concentration to CO2 release at different rates were quantified and will be shown at this presentation. Fig.2 shows some examples of the results. The different responses at the impact and control sites are used to assess the effectiveness for CO2 surface and near-surface detection when a possible CO2 leakage occurs.ig.1. A schematic showing the injection and release of CO2 at an agricultral plot in Bozeman, MT. ig.2. Some examples of results showing the response of vegetation, hyperspectral reflectance, soil electric conductivity, soil O2 concentration to the release of CO2.

  8. Membrane separation of hydrocarbons

    Science.gov (United States)

    Chang, Y. Alice; Kulkarni, Sudhir S.; Funk, Edward W.

    1986-01-01

    Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture through a polymeric membrane. The membrane which is utilized to effect the separation comprises a polymer which is capable of maintaining its integrity in the presence of hydrocarbon compounds and which has been modified by being subjected to the action of a sulfonating agent. Sulfonating agents which may be employed will include fuming sulfuric acid, chlorosulfonic acid, sulfur trioxide, etc., the surface or bulk modified polymer will contain a degree of sulfonation ranging from about 15 to about 50%. The separation process is effected at temperatures ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psig.

  9. Mapping 3D thin shale and permeability pathway within a reservoir system: Case study from the Sleipner Field

    Science.gov (United States)

    Ponfa Bitrus, Roy; Iacopini, David; Bond, Clare

    2016-04-01

    Reservoir architecture plays an integral part of seismic reservoir characterization. The characteristics of a reservoir which includes its external and internal geometry are important as they influence the production and development strategy employed in the oil and gas sector. Reservoir architecture is defined by the interpretation of seismic data, thus identifying the basic structural and stratigraphic geometrical framework of a trapping and flow system for hydrocarbon and fluids. One major issue though is the interpretation of thin shales and identification of permeability pathways within the reservoir system. This paper employs a method using attributes to map thin shales and identify permeability pathways or transmissitives that exist within a reservoir taking into consideration the seismic resolution and available data. Case study is the Utsira Formation in the Sleipner field, Norwegian North sea. The Utsira formation presents a classic case of thin beds within a sandstone formation and transmissitives that exist as chimneys within the formation. A total of 10 intra reservoir horizon units of shales where interpreted using complex trace seismic attributes. These interpreted horizons where further analysed through spectral decomposition to reveal possible facies distribution and unit thickness within the horizon. Reservoir transmissitives identified as vertical curvilinear structures were also analysed using unique seismic attributes in other to delineate their extent and characterise their occurrence These interpreted shales and pathway transmissitives illuminate the geometry of the formation, the reservoir heterogeneities on a finer-scale and, in the long term, constrain the migration prediction of reservoir fluids, hydrocarbons and injected CO2 when matched across a 4D seismic data survey. As such, useful insights into the key elements operating within the reservoir can be provided, giving a good indication of the long and short term reservoir performance.

  10. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  11. Air-leakage effects on stone cladding panels

    Science.gov (United States)

    Colantonio, Antonio

    1995-03-01

    This paper looks at the effects of air leakage on insulated stone clad precast panels used in present day construction of large commercial buildings. The building investigated was a newly built twenty story office building in a high density urban setting. Air leakage was suspected as a possible cause for thermal comfort complaints at isolated locations within the perimeter zones of the building. During the warrantee period the building owner asked for a quality control inspection of the air barrier assembly of the building envelope. Infrared thermography was used to locate areas of suspected air leakage within the building envelope. In order to differentiate thermal patterns produced by air leakage, conduction and convection as well as radiation from external sources, the building was inspected from the exterior; (1) after being pressurized for three hours, (2) one hour after the building was depressurized and (3) two and a half hours after total building depressurization was maintained by the building mechanical systems. Thermal images from similar locations were correlated for each time and pressure setting to verify air leakage locations within the building envelope. Areas exhibiting air leakage were identified and contractors were requested to carry out the necessary repairs. The pressure differential across the building envelope needs to be known in order to properly carry out an inspection to identify all locations of air leakage within a building envelope. As well the direction of the air movement and the density of the cladding material need to be accounted for in the proper inspection of these types of wall assemblies.

  12. THERMOCHEMISTRY OF HYDROCARBON RADICALS

    Energy Technology Data Exchange (ETDEWEB)

    Kent M. Ervin, Principal Investigator

    2004-08-17

    Gas phase negative ion chemistry methods are employed to determine enthalpies of formation of hydrocarbon radicals that are important in combustion processes and to investigate the dynamics of ion-molecule reactions. Using guided ion beam tandem mass spectrometry, we measure collisional threshold energies of endoergic proton transfer and hydrogen atom transfer reactions of hydrocarbon molecules with negative reagent ions. The measured reaction threshold energies for proton transfer yield the relative gas phase acidities. In an alternative methodology, competitive collision-induced dissociation of proton-bound ion-molecule complexes provides accurate gas phase acidities relative to a reference acid. Combined with the electron affinity of the R {center_dot} radical, the gas phase acidity yields the RH bond dissociation energy of the corresponding neutral molecule, or equivalently the enthalpy of formation of the R{center_dot} organic radical, using equation: D(R-H) = {Delta}{sub acid}H(RH) + EA(R) - IE(H). The threshold energy for hydrogen abstraction from a hydrocarbon molecule yields its hydrogen atom affinity relative to the reagent anion, providing the RH bond dissociation energy directly. Electronic structure calculations are used to evaluate the possibility of potential energy barriers or dynamical constrictions along the reaction path, and as input for RRKM and phase space theory calculations. In newer experiments, we have measured the product velocity distributions to obtain additional information on the energetics and dynamics of the reactions.

  13. Asphalt features and gas accumulation mechanism of Sinian reservoirs in the Tongwan Palaeo-uplift, Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Wei Li

    2015-10-01

    Full Text Available Breakthroughs have been made in natural gas exploration in Sinian reservoirs in the Tongwan Palaeo-uplift, Sichuan Basin, recently. However, there are disputes with regard to the genetic mechanisms of natural gas reservoirs. The development law of asphalts in the Sinian reservoirs may play an extremely important role in the study of the relationships between palaeo oil and gas reservoirs. Accordingly, researches were conducted on the features and development patterns of asphalts in the Sinian reservoirs in this area. The following research results were obtained. (1 Asphalts in the Sinian reservoirs were developed after the important hydrothermal event in the Sichuan Basin, namely the well-known Emei Taphrogeny in the mid-late Permian Period. (2 Distribution of asphalts is related to palaeo oil reservoirs under the control of palaeo-structures of Indosinian-Yanshanian Period, when the palaeo-structures contained high content of asphalts in the high positions of the palaeo-uplift. (3 Large-scale oil and gas accumulations in the Sinian reservoirs occurred in the Indosinian-Yanshanian Period to generate the Leshan-Ziyang and Gaoshiti-Moxi-Guang'an palaeo oil reservoirs. Cracking of crude oil in the major parts of these palaeo oil reservoirs controlled the development of the present natural gas reservoirs. (4 The development of asphalts in the Sinian reservoirs indicates that hydrocarbons in the Dengying Formation originated from Cambrian source rocks and natural gas accumulated in the Sinian reservoirs are products of late-stage cracking of the Sinian reservoirs. (5 The Sinian palaeo-structures of Indosinian-Yanshanian Period in the Sichuan Basin are favorable regions for the development of the Sinian reservoirs, where discoveries and exploration practices will play an important role in the era of Sinian natural gas development in China.

  14. Effects of Geometry on Leakage Flow Characteristics of Brush Seal

    Institute of Scientific and Technical Information of China (English)

    Yuan Wei; Zhaobo Chen∗; Yinghou Jiao

    2015-01-01

    In order to better application of brush seal in rotating machinery, the leakage flow characteristics of the brush seal considering geometry effects are numerically analyzed using Reynolds⁃Averaged Navier⁃Stokes ( RANS) model coupling with a non⁃Darcian porous medium model. The reliability of the present numerical method is proved, which is in agreement with the experimental and numerical results from literatures. Three different bristle pack thicknesses, fence heights and initial clearances under different pressure ratios, rotational velocities and other operating conditions are utilized to investigate the effects of geometry modification on the brush seal leakage flow behaviors. It discusses the effectiveness of various geometry configurations outlining important flow features. The results indicate that the increase of fence height and clearance would lead to the increase of leakage rate. But the leakage is not linearly with respect to the bristle pack thickness, and the effect of rotational velocity is not obvious. Moreover, the detailed leakage flow fields and pressure distributions along the rotor surface, free bristle height, and fence height of the brush seals are also presented. The static pressure drop amplitude through the bristle pack and the pressure rise amplitude through the cavity would increase while the pressure differential increases. And the axial pressure is the main reason of bristle blow down. The results provide theoretical support for the brush seal structure optimal design.

  15. Report on the water leakage from instrumentation pipe in JMTR

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-03-01

    On December 10, 2002, the leakage was found at the pressure instrumentation pipe attached to the exit pipe of No.1 charging pump of the purification system of a primary cooling system at JMTR in the Oarai Research establishment, JAERI. The Investigation Committee for Water Leakage from Instrumentation Pipe in JMTR was established and organized by specialists from inside and outside JAERI on December 16 and its meeting was held in public 3 times by 6th January, 2003. They found out the cause and countermeasures of cracks, and also investigated enhancement of safety management. As the result, it was considered that the leakage started around the 6th of December 2002 and the cause of the cracks was due to fatigue by vibration of the charging pump during operation. The committee discovered following incorrect actions in the safety management. First, operation of JMTR was continued without keeping careful watch in spite of occurrence of leakage detector alarm. Second, every time when the alarm range for the reasons other than the leakage, appropriate investigation and countermeasure were not taken. Third, the manager in charge didn't have a fair understanding of the situation and didn't give an appropriate direction. This is the report on the cause and countermeasures of cracks and enhancement of safety management. (author)

  16. Radio frequency leakage current from unipolar laparoscopic electrocoagulators.

    Science.gov (United States)

    DiNovo, J A

    1983-09-01

    Radio frequency (RF) leakage current has been suspected of causing accidental tissue burns associated with laparoscopic electrocoagulation used for tubal sterilization. A study was done to determine the levels of capacitively coupled RF leakage current from six unipolar laparoscopes manufactured by five companies. Leakage current values ranging from less than 100 mA to over 550 mA were measured at electrosurgical unit power settings of up to 150 w into 1,000 ohms. These levels represent 24-62% of the total electrosurgical current generated by the electrosurgical units. Using a criterion for tissue injury of 100 mA/sq cm applied for ten seconds, leakage current levels exceeding 400 mA are capable of producing burns either at the abdominal wall or to internal organs that accidentally come into contact with the body of the laparoscope. One of the six devices tested had leakage current levels higher than 400 mA at power settings lower than 100 w. Capacitance measurements between the unipolar laparoscope body and the forceps ranged from 53 to 140 picofarads.

  17. Suppression and control of leakage field in electromagnetic helical microwiggler

    Energy Technology Data Exchange (ETDEWEB)

    Ohigashi, N. [Kansai Univ., Osaka (Japan); Tsunawaki, Y. [Osaka Sangyo Univ. (Japan); Imasaki, K. [Institute for Laser Technology, Osaka (Japan)] [and others

    1995-12-31

    Shortening the period of electromagnetic wiggler introduces both the radical increase of the leakage field and the decrease of the field in the gap region. The leakage field is severer problem in planar electromagnetic wiggler than in helical wiggler. Hence, in order to develop a short period electromagnetic wiggler, we have adopted {open_quotes}three poles per period{close_quotes} type electromagnetic helical microwiggler. In this work, we inserted the permanent magnet (PM) blocks with specific magnetized directions in the space between magnetic poles, for suppressing the leakage field flowing out from a pole face to the neighboring pole face. These PM-blocks must have higher intrinsic coersive force than saturation field of pole material. The gap field due to each pole is adjustable by controlling the leakage fields, that is, controlling the position of each iron screw set in each retainer fixing the PM-blocks. At present time, a test wiggler with period 7.8mm, periodical number 10 and gap length 4.6mm has been manufactured. Because the ratio of PM-block aperture to gap length is important parameter to suppress the leakage field, the parameter has been surveyed experimentally for PM-blocks with several dimensions of aperture. The field strength of 3-5kG (K=0.2-0.4) would be expected in the wiggler.

  18. Reservoir geomechanics: new approach to reservoir engineering analysis

    Energy Technology Data Exchange (ETDEWEB)

    Settari, A.; Walters, D.A.; Behie, G.A. [Duke Engineering and Services Inc., Calgary, AB (Canada)

    1999-07-01

    The rock mechanics aspects of reservoir behavior are reviewed, and a description is included of some recent trends in coupled reservoir and strata mechanics modelling. Case histories are summarized which are field applications of these new trends and tools. These case histories include: (1) high rate injection into an oil sand reservoir; (2) compaction modelling of a North Sea reservoir; and (3) brine disposal at a fracturing pressure. Coupled geomechanical modelling is feasible on a full field scale, and it provides flexibility in the degree of coupling and calculational efficiency. The scope of interest in data gathering and characterization must be extended beyond reservoir boundaries because of the coupled modelling approach. This modelling provides results that can be employed in integrated reservoir management that includes reservoir engineering, drilling and completions. Considering the three case histories, coupled modelling can be used for predicting fracture initiation and re-orientation, reservoir compaction and deformations, and enhancement of injectivity due to stress dependent formation properties. Coupled modelling has brought reservoir modelling to a new realistic level and produces significant economic gains. 15 refs., 8 figs.

  19. Formation mechanisms and distribution of high quality reservoirs in deep strata in Palaeogene in northern steep slope zone of Bonan sag, Jiyang depression, China

    Institute of Scientific and Technical Information of China (English)

    马奔奔; 操应长; 贾艳聪; 王艳忠

    2015-01-01

    Petrographic analysis combined with various techniques, such as thin section identification, petro-physical property testing, mercury penetration, oil testing results, was used to assess basic reservoir characteristics of deep strata in Palaeogene in the northern steep slope zone of the Bonan sag, China. The formation mechanisms of high quality reservoirs in deep strata were discussed according to evolution characteristics of paleopressures and paleofluids in geological period. The deep reservoirs have poor physical properties and mainly develop extra-low porosity, extra-low and ultra-low permeability reservoirs. Reservoir spaces mainly consist of secondary pores and overpressure fractures. Early overpressure, early hydrocarbon filling and dissolution by early organic acids are the major formation mechanisms of high quality reservoirs. The conglomerate in inner fan which had a poor primary physical property mainly experienced strong compaction and calcareous matrix recrystallization. The physical properties of the inner fan were poor with weak dissolution because of poor mobility of fluid. The reservoirs mainly are type IV reservoirs and the distribution extends with the burial depth. The braided channel reservoirs in the middle fan had relative good primary physical properties and strong ability to resist compaction which favored the preservation of primary pores. Large amounts of the secondary porosities were created due to dissolution by early organic acids. A series of micro-fractures generated by early overpressures would be important migration pathways for hydrocarbon and organic acids. Furthermore, early overpressures had retarded maturation of organic matters and organic acids which had flowed into reservoirs already and could keep in acid environment for a long time. This process would contribute significantly to reinforcing the dissolution and enhancing the reservoir quality. The braided channel reservoirs were charged with high oil saturation

  20. Fingerprinting aliphatic hydrocarbon pollutants over agricultural lands surrounding Tehran oil refinery.

    Science.gov (United States)

    Bayat, Javad; Hashemi, Seyed Hossein; Khoshbakht, Korros; Deihimfard, Reza

    2016-11-01

    The analysis of aliphatic hydrocarbons, which are composed of n-alkanes as well as branched and cyclic alkanes, can be used to distinguish between the sources of hydrocarbon contamination. In this study, the concentration of aliphatic hydrocarbons, soil pH, and organic matter in agricultural soils located south of Tehran were monitored. Eighty-three soil samples were taken from two depth ranges of 0-30 and 30-60 cm. The results showed that aliphatic compounds ranged from 0.22-68.11 mg kg(-1) at the top to 0.33-53.18 mg kg(-1) at subsoil. The amount of hydrocarbons increases from the northern parts toward the south, and hydrocarbon pollutants originated from both petroleum and non-petroleum sources. Higher concentrations of aliphatic compounds in the southern parts indicated that, aside from the practice of irrigating with untreated wastewater, leakage from oil refinery storage tanks possibly contributed to soil pollution. The results also showed that several sources have polluted the agricultural soils. It is necessary to develop a new local pollution criterion as a diagnostic index that includes not only hydrocarbons but also other parameters such as heavy metal content in both soil and untreated wastewater, surface runoff, and other irrigation water resources to determine the exact origin of pollution.

  1. Geothermal reservoir management

    Energy Technology Data Exchange (ETDEWEB)

    Scherer, C.R.; Golabi, K.

    1978-02-01

    The optimal management of a hot water geothermal reservoir was considered. The physical system investigated includes a three-dimensional aquifer from which hot water is pumped and circulated through a heat exchanger. Heat removed from the geothermal fluid is transferred to a building complex or other facility for space heating. After passing through the heat exchanger, the (now cooled) geothermal fluid is reinjected into the aquifer. This cools the reservoir at a rate predicted by an expression relating pumping rate, time, and production hole temperature. The economic model proposed in the study maximizes discounted value of energy transferred across the heat exchanger minus the discounted cost of wells, equipment, and pumping energy. The real value of energy is assumed to increase at r percent per year. A major decision variable is the production or pumping rate (which is constant over the project life). Other decision variables in this optimization are production timing, reinjection temperature, and the economic life of the reservoir at the selected pumping rate. Results show that waiting time to production and production life increases as r increases and decreases as the discount rate increases. Production rate decreases as r increases and increases as the discount rate increases. The optimal injection temperature is very close to the temperature of the steam produced on the other side of the heat exchanger, and is virtually independent of r and the discount rate. Sensitivity of the decision variables to geohydrological parameters was also investigated. Initial aquifer temperature and permeability have a major influence on these variables, although aquifer porosity is of less importance. A penalty was considered for production delay after the lease is granted.

  2. Geology and hydrocarbon potential of the Oued Mya basin, Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Benamrane, O.; Messaoudi, M.; Messelles, H. (Sonatrach Division Exploration, Algiers (Algeria))

    1993-09-01

    The Oued Mya hydrocarbon system is located in the Sahara basin. It is one of the best producing basins in Algeria, along with the Ghadames and Illizi basins. The stratigraphic section consists of Paleozoic and Mesozoic, and is about 5000 m thick. This intracratonic basin is limited to the north by the Toughourt saddle, and to the west and east it is flanked by regional arches, Allal-Tilghemt and Amguid-Hassi Messaoud, which culminate in the super giant Hassi Messaoud and Hassi R'mel hydrocarbon accumulations, respectively, producing oil from the Cambrian sands and gas from the Trissic sands. The primary source rock in this basin is lower Silurian shale, with an average thickness of 50 m and a total organic carbon of 6% (14% in some cases). Results of maturation modeling indicate that the lower Silurian source is in the oil window. The Ordovician shales are also source rocks, but in a second order. Clastic reservoirs are in the Trissic sequence, which is mainly fluvial deposits with complex alluvial channels, and the main target in the basin. Clastic reservoirs in the lower Devonian section have a good hydrocarbon potential east of the basin through a southwest-northwest orientation. The Late Trissic-Early Jurassic evaporites that overlie the Triassic clastic interval and extend over the entire Oued Mya basin, are considered to be a super-seal evaporite package, which consists predominantly of anhydrite and halite. For paleozoic targets, a large number of potential seals exist within the stratigraphic column. This super seal does not present oil dismigration possibilities. We can infer that a large amount of the oil generated by the Silurian source rock from the beginning of Cretaceous until now still is not discovered and significantly greater volumes could be trapped within structure closures and mixed or stratigraphic traps related to the fluvial Triassic sandstones, marine Devonian sands, and Cambrian-Ordovician reservoirs.

  3. Impact of the Indonesian throughflow on Agulhas leakage

    Directory of Open Access Journals (Sweden)

    D. Le Bars

    2013-02-01

    Full Text Available Using ocean models of different complexity we show that opening the Indonesian Passage between the Pacific and the Indian Ocean increases the input of Indian Ocean water into the South Atlantic via the Agulhas leakage. In a strongly eddying global ocean model this response results from an increased Agulhas Current transport and a constant proportion of Agulhas retroflection south of Africa. The leakage increases through an increased frequency of ring shedding events. In an idealized two-layer and flat-bottom eddy resolving model, the proportion of the Agulhas Current transport that retroflects is (for a wide range of wind stress forcing not affected by an opening of the Indonesian Passage. A linear ocean model is not able to explain this behavior which reveals the importance of mixed barotropic/baroclinic instabilities in controlling the Agulhas leakage.

  4. An Investigation of Tendon Corrosion-Inhibitor Leakage into Concrete

    Energy Technology Data Exchange (ETDEWEB)

    Costello, J.F.; Naus, D.J.; Oland, C.B.

    1999-07-05

    During inspections performed at US nuclear power plants several years ago, some of the prestressed concrete containment had experienced leakage of the tendon sheathing filler. A study was conducted to indicate the extent of the leakage into the concrete and its potential effects on concrete properties. Concrete core samples were obtained from the Trojan Nuclear Plant. Examination and testing of the core samples indicated that the appearance of tendon sheathing filler on the surface was due to leakage of the filler from the conduits and its subsequent migration to the concrete surface through cracks that were present. Migration of the tendon sheathing filler was confined to the cracks with no perceptible movement into the concrete. Results of compressive strength tests indicated that the concrete quality was consistent in the containment and that the strength had increased relative to the strength at 28 days age.

  5. Leakage radiation microscope for observation of non-transparent samples.

    Science.gov (United States)

    Merlo, Juan M; Ye, Fan; Burns, Michael J; Naughton, Michael J

    2014-09-22

    We describe a leakage radiation microscope technique that can be used to extend the leakage radiation microscopy to optically non-transparent samples. In particular, two experiments are presented, first to demonstrate that acquired images with our configuration correspond to the leakage radiation phenomenon and second, to show possible applications by directly imaging a plasmonic structure that previously could only be imaged with a near-field scanning optical microscope. It is shown that the measured surface plasmon wavelength and propagation length agree with theoretically-calculated values. This configuration opens the possibility to study important effects where samples are optically non-transparent, as in plasmonic cavities and single hole plasmonic excitation, without the use of time-consuming near-field scanning optical microscopy.

  6. Reducing water leakage into underground coal mines by aquifer dewatering

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, J. P.

    1978-01-01

    Based on stratigraphic, structural, hydrogeologic, and mining data collected during a study in central Pennsylvania, a two-dimensional, finite-difference computer model was used to simulate groundwater flow in a sandstone unit (0.3 to 11 m thick) overlying an underground mine, and to evaluate the responses of the flow system and leakage rate into the mine when hypothetical dewatering wells are introduced into the system. Simulation of well dewatering, using 25 wells, showed that negligible reduction in leakage would occur if sandstone permeability was less than 0.30 m/day. When sandstone permeability equalled 3.0 m/day, 25 wells reduced leakage by 2.4 percent.

  7. Air Leakage Rates in Typical Air Barrier Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Hun, Diana E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Atchley, Jerald Allen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Childs, Phillip W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-11-01

    Estimates for 2010 indicate that infiltration in residential buildings was responsible for 2.85 quads of energy (DOE 2014), which is about 3% of the total energy consumed in the US. One of the mechanisms being implemented to reduce this energy penalty is the use of air barriers as part of the building envelope. These technologies decrease airflow through major leakage sites such as oriented strand board (OSB) joints, and gaps around penetrations (e.g., windows, doors, pipes, electrical outlets) as indicated by Hun et al. (2014). However, most air barrier materials do not properly address leakage spots such as wall-to-roof joints and wall-to-foundation joints because these are difficult to seal, and because air barrier manufacturers usually do not provide adequate instructions for these locations. The present study focuses on characterizing typical air leakage sites in wall assemblies with air barrier materials.

  8. Understanding Instrumental Stokes Leakage in Murchison Widefield Array Polarimetry

    CERN Document Server

    Sutinjo, Adrian; Lenc, Emil; Wayth, Randall B; Padhi, Shantanu; Hall, Peter; Tingay, Steven J

    2014-01-01

    This paper offers an electromagnetic, more specifically array theory, perspective on understanding strong instrumental polarization effects for planar low-frequency "aperture arrays" with the Murchison Widefield Array (MWA) as an example. A long-standing issue that has been seen here is significant instrumental Stokes leakage after calibration, particularly in Stokes Q at high frequencies. A simple model that accounts for inter-element mutual coupling is presented which explains the prominence of Q leakage seen when the array is scanned away from zenith in the principal planes. On these planes, the model predicts current imbalance in the X (E-W) and Y (N-S) dipoles and hence the Q leakage. Although helpful in concept, we find that this model is inadequate to explain the full details of the observation data. This finding motivates further experimentation with more rigorous models that account for both mutual coupling and embedded element patterns. Two more rigorous models are discussed: the "full" and "average...

  9. Functions and requirements for single-shell tank leakage mitigation

    Energy Technology Data Exchange (ETDEWEB)

    Cruse, J.M.

    1994-09-22

    This document provides the initial functions and requirements for the leakage mitigation mission applicable to past and potential future leakage from the Hanford Site`s 149 single-shell high-level waste tanks. This mission is a part of the overall mission of the Westinghouse Hanford Company Tank Waste Remediation System division to remediate the tank waste in a safe and acceptable manner. Systems engineering principles are being applied to this effort. A Mission Analysis has been completed, this document reflects the next step in the systems engineering approach to decompose the mission into primary functions and requirements. The functions and requirements in this document apply to mitigative actions to be taken regarding below ground leaks from SST containment boundaries and the resulting soil contamination. Leakage mitigation is invoked in the TWRS Program in three fourth level functions: (1) Store Waste, (2) Retrieve Waste, and (3) Disposition Excess Facilities.

  10. Power Beaming Leakage Radiation as a SETI Observable

    CERN Document Server

    Benford, James N

    2016-01-01

    The most observable leakage radiation from an advanced civilization may well be from the use of power beaming to transfer energy and accelerate spacecraft. Applications suggested for power beaming involve Earth-to-space applications such as launching spacecraft to orbit, raising satellites to a higher orbit, and interplanetary concepts involving space-to-space transfers of cargo or passengers. We also quantify beam-driven launch to the outer solar system, interstellar precursors and ultimately starships. We estimate the principal observable parameters of power beaming leakage. Extraterrestrial civilizations would know their power beams could be observed, and so could put a message on the power beam and broadcast it for our receipt at little additional energy or cost. By observing leakage from power beams we may find a message embedded on the beam. Recent observations of the anomalous star KIC 8462852 by the Allen Telescope Array (ATA) set some limits on extraterrestrial power beaming in that system. We show t...

  11. Geochemistry of hydrocarbons of the Terek-Caspian trough

    Directory of Open Access Journals (Sweden)

    N.Sh. Yandarbiev

    2017-05-01

    Full Text Available Within the Terek-Caspian oil and gas bearing basin of the Eastern Ciscaucasia, oil deposits occur in a wide stratigraphic range of rocks of the Mesozoic-Cenozoic section, from the Jurassic, at depths from 5800 to 200 m. In the sedimentary section, carbonate and terrigenous Middle Jurassic, Lower Cretaceous, Oligocene-Lower Miocene and Miocene oil-mother rocks are distinguished. Organic matter from them have different geochemical characteristics and different maturity to realize the generation potential. The article presents the results of a comprehensive study of potential petroleum-bearing rocks and hydrocarbon fluids from the Terek-Sunzha folded zone of the Terek-Caspian Trough, including lithological, chemical-bituminological, pyrolytic, chromatographic and chromatographic-mass spectrometry investigations. A detailed description of hydrocarbon fluids at the molecular level and genetic correlations of oil-oil and oil-organic matter are given. Specific features of the oil deposits of the Mesozoic-Cenozoic section are noted. Among the studied bitumens, the chromatographic characteristics of the extractable organic matter from the Khadum carbonate-clayey deposits and oils from the Cretaceous and Neogene reservoirs are most similar. The composition of a complex natural mixture of hydrocarbons from various sources, with different maturation during the geological history of the region, does not allow making unambiguous conclusions about the source or sources of hydrocarbons for the deposits of the Terek-Caspian Trough.

  12. Characterization of the Qishn sandstone reservoir, Masila Basin-Yemen, using an integrated petrophysical and seismic structural approach

    Science.gov (United States)

    Lashin, Aref; Marta, Ebrahim Bin; Khamis, Mohamed

    2016-03-01

    This study presents an integrated petrophysical and seismic structural analysis that is carried out to evaluate the reservoir properties of Qishn sandstone as well as the entrapment style of the hydrocarbons at Sharyoof field, Sayun-Masila Basin that is located at the east central of Yemen. The reservoir rocks are dominated by clean porous and permeable sandstones zones usually intercalated with some clay stone interbeds. As identified from well logs, Qishn sandstone is classified into subunits (S1A, S1B, S1C and S2) with different reservoir characteristics and hydrocarbon potentiality. A number of qualitative and quantitative well logging analyses are used to characterize the different subunits of the Qishn reservoir and identify its hydrocarbon potentiality. Dia-porosity, M-N, Pickett, Buckles plots, petrophysical analogs and lateral distribution maps are used in the analysis. Shale volume, lithology, porosity, and fluid saturation are among the most important deduced parameters. The analysis revealed that S1A and S1C are the main hydrocarbon-bearing units. More specifically, S1A unit is the best, as it attains the most prolific hydrocarbon saturations (oil saturation "SH″ up to 65) and reservoir characteristics. An average petrophysical ranges of 4-21%, 16-23%, 11-19%, 0-65%, are detected for S1A unit, regarding shale volume, total and effective porosity, and hydrocarbon saturation, respectively. Meanwhile, S1B unit exhibits less reservoir characteristics (Vsh>30%, ϕEff<15% and SH< 15%). The lateral distribution maps revealed that most of the hydrocarbons (for S1A and S1C units) are indicated at the middle of the study area as NE-SW oriented closures. The analysis and interpretation of seismic data had clarified that the structure of study area is represented by a big middle horst bounded by a group of step-like normal faults at the extreme boundaries (faulted anticlinal-structure). In conclusion, the entrapment of the encountered hydrocarbon at Sharyoof oil

  13. The controlling factors and distribution prediction of H2S formation in marine carbonate gas reservoir, China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Generally, there are some anhydrites in carbonate reservoir, as H2S is also familiar in carbonate oil and gas reservoirs. Nowadays, natural gas with high H2S concentration is usually considered as TSR origin,so there is close relationship between H2S and anhydrite. On the contrary, some carbonate rocks with anhydrite do not contain H2S. Recently, researches show that H2S isonly a necessary condition of H2S formation. The reservoir porosity, sulfate ion content within formation water, reservoir temperature,oil/gas and water interface, hydrocarbon and some elements of reservoir rock have great controlling effects on the TSR occurrence. TSR deoxidizes hydrocarbon into the acidic gas such as H2S and CO2,and the H2S formation is controlled by TSR occurrence, so the relationship among reaction room, the contact chance of sulfate ion and hydrocarbon, the reservoir temperature has great influence on the TSR reaction. H2S has relatively active chemical quality, so it is still controlled by the content of heavy metal ion. Good conditions of TSR reaction and H2S preservation are the prerequisite of H2S distribution prediction. This paper builds a predictive model based on the characteristic of natural gas reservoir with high H2S-bearing. In the porosity reservoir with anhydrite, the formation water is rich in sulfate and poor in heavy metal ion. Oil and gas fill and accumulate in the gas reservoir with good preservation conditions, and they suffered high temperature later, which indicates the profitable area of natural gas with high H2S-bearing.

  14. Some open issues in the analysis of the storage and migration properties of fractured carbonate reservoirs

    Science.gov (United States)

    Agosta, Fabrizio

    2017-04-01

    Underground CO2 storage in depleted hydrocarbon reservoirs may become a common practice in the future to lower the concentration of greenhouse gases in the atmosphere. Results from the first experiments conducted in carbonate rocks, for instance the Lacq integrated CCS Pilot site, SW France, are quite exciting. All monitored parameters, such as the CO2 concentration at well sites, well pressures, cap rock integrity and environmental indicators show the long-term integrity of this type of geological reservoirs. Other positive news arise from the OXY-CFB-300 Compostilla Project, NW Spain, where most of the injected CO2 dissolved into the formation brines, suggesting the long-term security of this method. However, in both cases, the CO2- rich fluids partially dissolved the carbonate minerals during their migration through the fractured reservoir, modifying the overall pore volume and pressure regimes. These results support the growing need for a better understanding of the mechanical behavior of carbonate rocks over geological time of scales. In fact, it is well known that carbonates exhibit a variety of deformation mechanisms depending upon many intrinsic factors such as composition, texture, connected pore volume, and nature of the primary heterogeneities. Commonly, tight carbonates are prone to opening-mode and/or pressure solution deformation. The interplay between these two mechanisms likely affects the petrophysical properties of the fault damage zones, which form potential sites for CO2 storage due to their high values of both connected porosity and permeability. On the contrary, cataclastic deformation produces fault rocks that often form localized fluid barriers for cross-fault fluid flow. Nowadays, questions on the conditions of sealing/leakage of carbonate fault rocks are still open. In particular, the relative role played by bulk crushing, chipping, cementation, and pressure solution on connected porosity of carbonate fault rocks during structural

  15. First field example of remediation of unwanted migration from a natural CO2 reservoir: The Bečej Field, Serbia

    NARCIS (Netherlands)

    Karas, D.; Demić, I.; Kultysheva, K.; Antropov, A.; Blagojević, M.; Neele, F.; Pluymaekers, M.; Orlić, B.

    2016-01-01

    The Bečej field, discovered in 1951 by the Petroleum Industry of Serbia (NIS), is one of the largest natural CO2 fields in Europe. Uncontrolled migration of CO2 out of the main reservoir, leading to subsurface seepage and surface leakage, was caused by the Bč-5 well blowout in 1968. Remediation meas

  16. First field example of remediation of unwanted migration from a natural CO2 reservoir: The Bečej Field, Serbia

    NARCIS (Netherlands)

    Karas, D.; Demić, I.; Kultysheva, K.; Antropov, A.; Blagojević, M.; Neele, F.; Pluymaekers, M.; Orlić, B.

    2016-01-01

    The Bečej field, discovered in 1951 by the Petroleum Industry of Serbia (NIS), is one of the largest natural CO2 fields in Europe. Uncontrolled migration of CO2 out of the main reservoir, leading to subsurface seepage and surface leakage, was caused by the Bč-5 well blowout in 1968. Remediation meas

  17. Encapsulated microsensors for reservoir interrogation

    Energy Technology Data Exchange (ETDEWEB)

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.

    2016-03-08

    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  18. Reservoir management cost-cutting

    Energy Technology Data Exchange (ETDEWEB)

    Gulati, M.S.

    1996-12-31

    This article by Mohinder S. Gulati, Chief Engineer, Unocal Geothermal Operations, discusses cost cutting in geothermal reservoir management. The reservoir engineer or geoscientist can make a big difference in the economical outcome of a project by improving well performance and thus making geothermal energy more competitive in the energy marketplace. Bringing plants online in less time and proving resources to reduce the cycle time are some of the ways to reduce reservoir management costs discussed in this article.

  19. Encapsulated microsensors for reservoir interrogation

    Science.gov (United States)

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.

    2016-03-08

    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  20. Cuffed Endotracheal Tube Size and Leakage in Pediatric Tracheal Models

    Directory of Open Access Journals (Sweden)

    Jun Hyun Kim

    2014-04-01

    Full Text Available Object: Cuffed endotracheal tubes are increasingly used in pediatric patients in the hope that they can reduce air leakage and tube size mismatch by just inflating the cuff. Authors compared influence of various tube sizes and different levels of cuff pressures to air leakage around the cuff, in artificial tracheal models. Methods: Six PVC cylinders of different internal diameters (ID: 8.15, 8.50, 9.70, 12.05, 14.50, and 20.00 mm were prepared. An artificial lung connected with cylinder was ventilated with an anesthesia machine. Cuffed endotracheal tubes of different sizes (ID 3.0~8.0 were located in the cylinders and the cuff was inflated with various pressures (15, 20, 25, 30 and 35 cm H2O. Expiratory tidal volume was measured with more than 25% loss of baseline expiratory tidal volume was considered significant air leakage. Results: Tube sizes same as, or larger than ID 5.0 didn’t show significant air leakage for any trachea model, only if the inflated cuff size is larger than the cylinder ID, except ID 5.5 tube at cuff pressure 15 cm H2O and 20 cm H2O, in 12.05 mm cylinder. Tubes sizes same as or smaller than ID 4.5, which have short cuff lengths and sizes than tubes larger than, or same as ID 5.0, leaked significantly at any tracheal models, except ID 4.5 tube at cuff pressure 35 cm H2O, in 8.50 mm cylinder. Conclusion: In PVC pediatric tracheal models, tubes same as, or smaller than ID 4.5 are inferior to tubes same as, or larger than ID 5.0 in preventing air leakage, and may need a higher cuff pressure to reduce air leakage. Further clinical studies could be designed based on our results.

  1. On camera-based smoke and gas leakage detection

    Energy Technology Data Exchange (ETDEWEB)

    Nyboe, Hans Olav

    1999-07-01

    Gas detectors are found in almost every part of industry and in many homes as well. An offshore oil or gas platform may host several hundred gas detectors. The ability of the common point and open path gas detectors to detect leakages depends on their location relative to the location of a gas cloud. This thesis describes the development of a passive volume gas detector, that is, one than will detect a leakage anywhere in the area monitored. After the consideration of several detection techniques it was decided to use an ordinary monochrome camera as sensor. Because a gas leakage may perturb the index of refraction, parts of the background appear to be displaced from their true positions, and it is necessary to develop algorithms that can deal with small differences between images. The thesis develops two such algorithms. Many image regions can be defined and several feature values can be computed for each region. The value of the features depends on the pattern in the image regions. The classes studied in this work are: reference, gas, smoke and human activity. Test show that observation belonging to these classes can be classified fairly high accuracy. The features in the feature set were chosen and developed for this particular application. Basically, the features measure the magnitude of pixel differences, size of detected phenomena and image distortion. Interesting results from many experiments are presented. Most important, the experiments show that apparent motion caused by a gas leakage or heat convection can be detected by means of a monochrome camera. Small leakages of methane can be detected at a range of about four metres. Other gases, such as butane, where the densities differ more from the density of air than the density of methane does, can be detected further from the camera. Gas leakages large enough to cause condensation have been detected at a camera distance of 20 metres. 59 refs., 42 figs., 13 tabs.

  2. EXPLOITATION AND OPTIMIZATION OF RESERVOIR PERFORMANCE IN HUNTON FORMATION, OKLAHOMA

    Energy Technology Data Exchange (ETDEWEB)

    Mohan Kelkar

    2005-02-01

    Hunton formation in Oklahoma has displayed some unique production characteristics. These include high initial water-oil and gas-oil ratios, decline in those ratios over time and temporary increase in gas-oil ratio during pressure build up. The formation also displays highly complex geology, but surprising hydrodynamic continuity. This report addresses three key issues related specifically to West Carney Hunton field and, in general, to any other Hunton formation exhibiting similar behavior: (1) What is the primary mechanism by which oil and gas is produced from the field? (2) How can the knowledge gained from studying the existing fields can be extended to other fields which have the potential to produce? (3) What can be done to improve the performance of this reservoir? We have developed a comprehensive model to explain the behavior of the reservoir. By using available production, geological, core and log data, we are able to develop a reservoir model which explains the production behavior in the reservoir. Using easily available information, such as log data, we have established the parameters needed for a field to be economically successful. We provide guidelines in terms of what to look for in a new field and how to develop it. Finally, through laboratory experiments, we show that surfactants can be used to improve the hydrocarbons recovery from the field. In addition, injection of CO{sub 2} or natural gas also will help us recover additional oil from the field.

  3. Advanced Reservoir Imaging Using Frequency-Dependent Seismic Attributes

    Energy Technology Data Exchange (ETDEWEB)

    Fred Hilterman; Tad Patzek; Gennady Goloshubin; Dmitriy Silin; Charlotte Sullivan; Valeri Korneev

    2007-12-31

    Our report concerning advanced imaging and interpretation technology includes the development of theory, the implementation of laboratory experiments and the verification of results using field data. We investigated a reflectivity model for porous fluid-saturated reservoirs and demonstrated that the frequency-dependent component of the reflection coefficient is asymptotically proportional to the reservoir fluid mobility. We also analyzed seismic data using different azimuths and offsets over physical models of fractures filled with air and water. By comparing our physical model synthetics to numerical data we have identified several diagnostic indicators for quantifying the fractures. Finally, we developed reflectivity transforms for predicting pore fluid and lithology using rock-property statistics from 500 reservoirs in both the shelf and deep-water Gulf of Mexico. With these transforms and seismic AVO gathers across the prospect and its down-dip water-equivalent reservoir, fluid saturation can be estimated without a calibration well that ties the seismic. Our research provides the important additional mechanisms to recognize, delineate, and validate new hydrocarbon reserves and assist in the development of producing fields.

  4. Preliminary Rock Physics Characterization of Mississippian Carbonate Reservoir in Canada

    Science.gov (United States)

    Lee, M.; Keehm, Y.; Kim, H.

    2011-12-01

    The Mississippian formations in the Western Canada Sedimentary Basin are known to have large hydrocarbon resources. The Lodgepole formation is the most important reservoir for oil production in Daly and Virden fields. In this study, we performed preliminary reservoir characterization using rock physics modeling. We first delineated the Lodgepole formation by geological information, well-logs and core analysis data. Then, we conducted rock physics analyses such as GR-AI, DEM modeling, porosity-Vp, density-Vp, and porosity-permeability. We identified the Lodgepole formation has different porosity types, volume of shale, and the degree of fractures in difference intervals. In the upper part of the formation, we found that vuggy pores are well developed. Inter-particular porosity and fractures become significant as the depth increases. We found that the lower part can be divided into two groups by acoustic impedance. The prospective reservoir interval, one of the two groups, has higher fracture density, which can be identified by lower acoustic impedance. This result also implies that we could also use AVO analyses to delineate good reservoir intervals. In conclusion, rock physics modeling can be effectively applied to characterize the Lodgepole formation quantitatively with well-log and core analysis data. Acknowledgement: This work was supported by the Energy Resources R&D program of the Korea Institute of Energy Technology Evaluation and Planning (KETEP) grant funded by the Korea government Ministry of Knowledge Economy (No. 2009201030001A).

  5. EXPLOITATION AND OPTIMIZATION OF RESERVOIR PERFORMANCE IN HUNTON FORMATION, OKLAHOMA

    Energy Technology Data Exchange (ETDEWEB)

    Mohan Kelkar

    2005-02-01

    Hunton formation in Oklahoma has displayed some unique production characteristics. These include high initial water-oil and gas-oil ratios, decline in those ratios over time and temporary increase in gas-oil ratio during pressure build up. The formation also displays highly complex geology, but surprising hydrodynamic continuity. This report addresses three key issues related specifically to West Carney Hunton field and, in general, to any other Hunton formation exhibiting similar behavior: (1) What is the primary mechanism by which oil and gas is produced from the field? (2) How can the knowledge gained from studying the existing fields can be extended to other fields which have the potential to produce? (3) What can be done to improve the performance of this reservoir? We have developed a comprehensive model to explain the behavior of the reservoir. By using available production, geological, core and log data, we are able to develop a reservoir model which explains the production behavior in the reservoir. Using easily available information, such as log data, we have established the parameters needed for a field to be economically successful. We provide guidelines in terms of what to look for in a new field and how to develop it. Finally, through laboratory experiments, we show that surfactants can be used to improve the hydrocarbons recovery from the field. In addition, injection of CO{sub 2} or natural gas also will help us recover additional oil from the field.

  6. Reservoir Operation to Minimize Sedimentation

    Directory of Open Access Journals (Sweden)

    Dyah Ari Wulandari

    2013-10-01

    Full Text Available The Wonogiri Reservoir capacity decreases rapidly, caused by serious sedimentation problems. In 2007, JICA was proposed a sediment storage reservoir with a new spillway for the purpose of sediment flushing / sluicing from The Keduang River. Due to the change of reservoir storage and change of reservoir system, it requires a sustainable reservoir operation technique. This technique is aimed to minimize the deviation between the input and output of sediments. The main objective of this study is to explore the optimal Wonogiri reservoir operation by minimizing the sediment trap. The CSUDP incremental dynamic programming procedure is used for the model optimization.  This new operating rules will also simulate a five years operation period, to show the effect of the implemented techniques. The result of the study are the newly developed reservoir operation system has many advantages when compared to the actual operation system and the disadvantage of this developed system is that the use is mainly designed for a wet hydrologic year, since its performance for the water supply is lower than the actual reservoir operations.Doi: 10.12777/ijse.6.1.16-23 [How to cite this article:  Wulandari, D.A., Legono, D., and Darsono, S., 2014. Reservoir Operation to Minimize Sedimentation. International Journal of Science and Engineering, 5(2,61-65. Doi: 10.12777/ijse.6.1.16-23] Normal 0 false false false EN-US X-NONE X-NONE

  7. All-optical reservoir computing.

    Science.gov (United States)

    Duport, François; Schneider, Bendix; Smerieri, Anteo; Haelterman, Marc; Massar, Serge

    2012-09-24

    Reservoir Computing is a novel computing paradigm that uses a nonlinear recurrent dynamical system to carry out information processing. Recent electronic and optoelectronic Reservoir Computers based on an architecture with a single nonlinear node and a delay loop have shown performance on standardized tasks comparable to state-of-the-art digital implementations. Here we report an all-optical implementation of a Reservoir Computer, made of off-the-shelf components for optical telecommunications. It uses the saturation of a semiconductor optical amplifier as nonlinearity. The present work shows that, within the Reservoir Computing paradigm, all-optical computing with state-of-the-art performance is possible.

  8. Reservoir geochemistry; Geoquimica de reservatorios

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Joelma Pimentel; Rangel, Mario Duncan; Morais, Erica Tavares de [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas (CENPES)], Emails: joelma.lopes@petrobras.com.br, mduncan@petrobras.com.br, ericat@petrobras.com.br; Aguiar, Helen G.M. de [Fundacao GORCEIX, Ouro Preto, MG (Brazil)], E-mail: helenaguiar.GORCEIX@petrobras.com.br

    2008-03-15

    Reservoir Geochemistry has many important practical applications during petroleum exploration, appraisal and development of oil fields. The most important uses are related to providing or disproving connectivity between reservoirs of a particular well or horizon. During exploration, reservoir geochemistry can indicate the direction of oil filling, suggesting the most appropriate places for drilling new wells. During production, studies of variations in composition with time and determination of proportions of commingled production from multiple zones, may also be carried out. The chemical constituents of petroleum in natural reservoirs frequently show measurable compositional variations, laterally and vertically. Due to the physical and chemical nature of petroleum changes with increasing maturity (or contribution of a second source during the filling process), lateral and vertical compositional variations exist in petroleum columns as reservoir filling is complete. Compositional variation can also be introduced by biodegradation or water washing. Once the reservoir is filled, density driven mixing and molecular diffusion tend to eliminate inherited compositional variations in an attempt to establish mechanical and chemical equilibrium in the petroleum column (England, 1990). Based on organic geochemical analysis it is possible to define these compositional variations among reservoirs, and use these data for developing of petroleum fields and for reservoir appraisal. Reservoir geochemistry offers rapid and low cost evaluation tools to aid in understanding development and production problems. Moreover, the applied methodology is relatively simple and gives reliable results, and can be performed routinely in any good geochemical laboratory at a relatively low cost. (author)

  9. Microvascular leakage of plasma proteins after PUVA and UVA

    Energy Technology Data Exchange (ETDEWEB)

    Staberg, B.; Worm, A.M.; Rossing, N.; Brodthagen, H.

    1982-04-01

    The transcapillary escape rate of albumin (TERalb), is a parameter of the leakage of macromolecules from the total microvasculature. In patients with psoriasis short-term PUVA treatment induces an increase in TERalb. In this study TERalb was measured in 3 groups of normal humans treated with PUVA, UVA and 8-methoxypsoralen. Treatment with PUVA and UVA caused a statistically significant increase in TERalb, whereas treatment with 8-methoxypsoralen did not induce any measurable changes. It is concluded that the UVA irradiation causes the abnormal leakage of macromolecules, whereas psoralen is not the responsible component. Furthermore the phenomenon can be elicited in normals and is not based on a preexisting psoriasis.

  10. Properties of Leakage Corrosion of Concrete and Its Durability

    Institute of Scientific and Technical Information of China (English)

    GE Xueliang; FANG Kunhe; ZENG Li; CHEN Xia

    2008-01-01

    The properties and mechanism of concrete under water leakage corrosion were studied in terms of the dissolution of calcium oxide and silicon oxide from concrete and the variation of pH value of permeate water.The experimental results show that the amount of calcium oxide and silicon oxide dissolved from per cubic meter of concrete gradually decrease with penetration time and ultimately stabilize at a certain value.The pH value of permeate water descend along with penetration time.The durability of concrete under leakage corrosion was analyzed by a formula fitted on the dissolved amount of calcium oxide.

  11. Second workshop geothermal reservoir engineering: Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Kruger, P.; Ramey, H.J. Jr. (eds.)

    1976-12-03

    The Arab oil embargo of 1973 focused national attention on energy problems. A national focus on development of energy sources alternative to consumption of hydrocarbons led to the initiation of research studies of reservoir engineering of geothermal systems, funded by the National Science Foundation. At that time it appeared that only two significant reservoir engineering studies of geothermal reservoirs had been completed. Many meetings concerning development of geothermal resources were held from 1973 through the date of the first Stanford Geothermal Reservoir Engineering workshop December 15-17, 1975. These meetings were similar in that many reports dealt with the objectives of planned research projects rather than with results. The first reservoir engineering workshop held under the Stanfo