WorldWideScience

Sample records for modeling reservoir characterization

  1. Spatial Stochastic Point Models for Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Syversveen, Anne Randi

    1997-12-31

    The main part of this thesis discusses stochastic modelling of geology in petroleum reservoirs. A marked point model is defined for objects against a background in a two-dimensional vertical cross section of the reservoir. The model handles conditioning on observations from more than one well for each object and contains interaction between objects, and the objects have the correct length distribution when penetrated by wells. The model is developed in a Bayesian setting. The model and the simulation algorithm are demonstrated by means of an example with simulated data. The thesis also deals with object recognition in image analysis, in a Bayesian framework, and with a special type of spatial Cox processes called log-Gaussian Cox processes. In these processes, the logarithm of the intensity function is a Gaussian process. The class of log-Gaussian Cox processes provides flexible models for clustering. The distribution of such a process is completely characterized by the intensity and the pair correlation function of the Cox process. 170 refs., 37 figs., 5 tabs.

  2. Development of Reservoir Characterization Techniques and Production Models for Exploiting Naturally Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Wiggins, M.L.; Evans, R.D.; Brown, R.L.; Gupta, A.

    2001-03-28

    This report focuses on integrating geoscience and engineering data to develop a consistent characterization of the naturally fractured reservoirs. During this reporting period, effort was focused on relating seismic data to reservoir properties of naturally fractured reservoirs, scaling well log data to generate interwell descriptors of these reservoirs, enhancing and debugging a naturally fractured reservoir simulator, and developing a horizontal wellbore model for use in the simulator.

  3. Development of Reservoir Characterization Techniques and Production Models for Exploiting Naturally Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Wiggins, Michael L.; Brown, Raymon L.; Civan, Frauk; Hughes, Richard G.

    2001-08-15

    Research continues on characterizing and modeling the behavior of naturally fractured reservoir systems. Work has progressed on developing techniques for estimating fracture properties from seismic and well log data, developing naturally fractured wellbore models, and developing a model to characterize the transfer of fluid from the matrix to the fracture system for use in the naturally fractured reservoir simulator.

  4. 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

  5. General approach to characterizing reservoir fluids for EoS models using a large PVT database

    DEFF Research Database (Denmark)

    Varzandeh, Farhad; Stenby, Erling Halfdan; Yan, Wei

    2017-01-01

    Fluid characterization is needed when applying any EoS model to reservoir fluids. It is important especially for non-cubic models such as PC-SAFT where fluid characterization is less mature. Furthermore, there is a great interest to apply non-cubic models to high pressure high temperature reservoir...

  6. Geological modeling for methane hydrate reservoir characterization in the eastern Nankai Trough, offshore Japan

    Science.gov (United States)

    Tamaki, M.; Komatsu, Y.; Suzuki, K.; Takayama, T.; Fujii, T.

    2012-12-01

    The eastern Nankai trough, which is located offshore of central Japan, is considered as an attractive potential resource field of methane hydrates. Japan Oil, Gas and Metals National Corporation is planning to conduct a production test in early 2013 at the AT1 site in the north slope of Daini-Atsumi Knoll in the eastern Nankai Trough. The depositional environment of methane hydrate-bearing sediments around the production test site is a deep submarine-fan turbidite system, and it is considered that the reservoir properties should show lateral as well as vertical heterogeneity. Since the variations in the reservoir heterogeneity have an impact on the methane hydrate dissociation and gas production performance, precise geological models describing reservoir heterogeneity would be required for the evaluation of reservoir potentials. In preparation for the production test, 3 wells; two monitoring boreholes (AT1-MC and AT1-MT1) and a coring well (AT1-C), were newly acquired in 2012. In addition to a geotechnical hole drilling survey in 2011 (AT1-GT), totally log data from 2 wells and core data from 2 wells were obtained around the production test site. In this study, we conducted well correlations between AT1 and A1 wells drilled in 2003 and then, 3D geological models were updated including AT1 well data in order to refine hydrate reservoir characterization around the production test site. The results of the well correlations show that turbidite sand layers are characterized by good lateral continuity, and give significant information for the distribution morphology of sand-rich channel fills. We also reviewed previously conducted 3D geological models which consist of facies distributions and petrophysical properties distributions constructed from integration of 3D seismic data and a well data (A1 site) adopting a geostatistical approach. In order to test the practical validity of the previously generated models, cross-validation was conducted using AT1 well data. The

  7. APPLICATION OF INTEGRATED RESERVOIR MANAGEMENT AND RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Jack Bergeron; Tom Blasingame; Louis Doublet; Mohan Kelkar; George Freeman; Jeff Callard; David Moore; David Davies; Richard Vessell; Brian Pregger; Bill Dixon; Bryce Bezant

    2000-03-01

    Reservoir performance and characterization are vital parameters during the development phase of a project. Infill drilling of wells on a uniform spacing, without regard to characterization does not optimize development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, especially carbonate reservoirs. These reservoirs are typically characterized by: (1) large, discontinuous pay intervals; (2) vertical and lateral changes in reservoir properties; (3) low reservoir energy; (4) high residual oil saturation; and (5) low recovery efficiency. The operational problems they encounter in these types of reservoirs include: (1) poor or inadequate completions and stimulations; (2) early water breakthrough; (3) poor reservoir sweep efficiency in contacting oil throughout the reservoir as well as in the nearby well regions; (4) channeling of injected fluids due to preferential fracturing caused by excessive injection rates; and (5) limited data availability and poor data quality. Infill drilling operations only need target areas of the reservoir which will be economically successful. If the most productive areas of a reservoir can be accurately identified by combining the results of geological, petrophysical, reservoir performance, and pressure transient analyses, then this ''integrated'' approach can be used to optimize reservoir performance during secondary and tertiary recovery operations without resorting to ''blanket'' infill drilling methods. New and emerging technologies such as geostatistical modeling, rock typing, and rigorous decline type curve analysis can be used to quantify reservoir quality and the degree of interwell communication. These results can then be used to develop a 3-D simulation model for prediction of infill locations. The application of reservoir surveillance techniques to identify additional reservoir ''pay'' zones

  8. 4. International reservoir characterization technical conference

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    This volume contains the Proceedings of the Fourth International Reservoir Characterization Technical Conference held March 2-4, 1997 in Houston, Texas. The theme for the conference was Advances in Reservoir Characterization for Effective Reservoir Management. On March 2, 1997, the DOE Class Workshop kicked off with tutorials by Dr. Steve Begg (BP Exploration) and Dr. Ganesh Thakur (Chevron). Tutorial presentations are not included in these Proceedings but may be available from the authors. The conference consisted of the following topics: data acquisition; reservoir modeling; scaling reservoir properties; and managing uncertainty. Selected papers have been processed separately for inclusion in the Energy Science and Technology database.

  9. Reservoir architecture modeling: Nonstationary models for quantitative geological characterization. Final report, April 30, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, D.; Epili, D.; Kelkar, M.; Redner, R.; Reynolds, A.

    1998-12-01

    The study was comprised of four investigations: facies architecture; seismic modeling and interpretation; Markov random field and Boolean models for geologic modeling of facies distribution; and estimation of geological architecture using the Bayesian/maximum entropy approach. This report discusses results from all four investigations. Investigations were performed using data from the E and F units of the Middle Frio Formation, Stratton Field, one of the major reservoir intervals in the Gulf Coast Basin.

  10. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    Energy Technology Data Exchange (ETDEWEB)

    None

    1998-01-01

    Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations.

  11. Characterization and modeling of turbidity density plume induced into stratified reservoir by flood runoffs.

    Science.gov (United States)

    Chung, S W; Lee, H S

    2009-01-01

    In monsoon climate area, turbidity flows typically induced by flood runoffs cause numerous environmental impacts such as impairment of fish habitat and river attraction, and degradation of water supply efficiency. This study was aimed to characterize the physical dynamics of turbidity plume induced into a stratified reservoir using field monitoring and numerical simulations, and to assess the effect of different withdrawal scenarios on the control of downstream water quality. Three different turbidity models (RUN1, RUN2, RUN3) were developed based on a two-dimensional laterally averaged hydrodynamic and transport model, and validated against field data. RUN1 assumed constant settling velocity of suspended sediment, while RUN2 estimated the settling velocity as a function of particle size, density, and water temperature to consider vertical stratification. RUN3 included a lumped first-order turbidity attenuation rate taking into account the effects of particles aggregation and degradable organic particles. RUN3 showed best performance in replicating the observed variations of in-reservoir and release turbidity. Numerical experiments implemented to assess the effectiveness of different withdrawal depths showed that the alterations of withdrawal depth can modify the pathway and flow regimes of the turbidity plume, but its effect on the control of release water quality could be trivial.

  12. Integrated reservoir characterization: Improvement in heterogeneities stochastic modelling by integration of additional external constraints

    Energy Technology Data Exchange (ETDEWEB)

    Doligez, B.; Eschard, R. [Institut Francais du Petrole, Rueil Malmaison (France); Geffroy, F. [Centre de Geostatistique, Fontainebleau (France)] [and others

    1997-08-01

    The classical approach to construct reservoir models is to start with a fine scale geological model which is informed with petrophysical properties. Then scaling-up techniques allow to obtain a reservoir model which is compatible with the fluid flow simulators. Geostatistical modelling techniques are widely used to build the geological models before scaling-up. These methods provide equiprobable images of the area under investigation, which honor the well data, and which variability is the same than the variability computed from the data. At an appraisal phase, when few data are available, or when the wells are insufficient to describe all the heterogeneities and the behavior of the field, additional constraints are needed to obtain a more realistic geological model. For example, seismic data or stratigraphic models can provide average reservoir information with an excellent areal coverage, but with a poor vertical resolution. New advances in modelisation techniques allow now to integrate this type of additional external information in order to constrain the simulations. In particular, 2D or 3D seismic derived information grids, or sand-shale ratios maps coming from stratigraphic models can be used as external drifts to compute the geological image of the reservoir at the fine scale. Examples are presented to illustrate the use of these new tools, their impact on the final reservoir model, and their sensitivity to some key parameters.

  13. Stochastic Reservoir Characterization Constrained by Seismic Data

    Energy Technology Data Exchange (ETDEWEB)

    Eide, Alfhild Lien

    1999-07-01

    In order to predict future production of oil and gas from a petroleum reservoir, it is important to have a good description of the reservoir in terms of geometry and physical parameters. This description is used as input to large numerical models for the fluid flow in the reservoir. With increased quality of seismic data, it is becoming possible to extend their use from the study of large geologic structures such as seismic horizons to characterization of the properties of the reservoir between the horizons. Uncertainties because of the low resolution of seismic data can be successfully handled by means of stochastic modeling, and spatial statistics can provide tools for interpolation and simulation of reservoir properties not completely resolved by seismic data. This thesis deals with stochastic reservoir modeling conditioned to seismic data and well data. Part I presents a new model for stochastic reservoir characterization conditioned to seismic traces. Part II deals with stochastic simulation of high resolution impedance conditioned to measured impedance. Part III develops a new stochastic model for calcite cemented objects in a sandstone background; it is a superposition of a marked point model for the calcites and a continuous model for the background.

  14. 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.

  15. A novel methodology improves reservoir characterization models using geologic fuzzy variables

    Energy Technology Data Exchange (ETDEWEB)

    Soto B, Rodolfo [DIGITOIL, Maracaibo (Venezuela); Soto O, David A. [Texas A and M University, College Station, TX (United States)

    2004-07-01

    One of the research projects carried out in Cusiana field to explain its rapid decline during the last years was to get better permeability models. The reservoir of this field has a complex layered system that it is not easy to model using conventional methods. The new technique included the development of porosity and permeability maps from cored wells following the same trend of the sand depositions for each facie or layer according to the sedimentary facie and the depositional system models. Then, we used fuzzy logic to reproduce those maps in three dimensions as geologic fuzzy variables. After multivariate statistical and factor analyses, we found independence and a good correlation coefficient between the geologic fuzzy variables and core permeability and porosity. This means, the geologic fuzzy variable could explain the fabric, the grain size and the pore geometry of the reservoir rock trough the field. Finally, we developed a neural network permeability model using porosity, gamma ray and the geologic fuzzy variable as input variables. This model has a cross-correlation coefficient of 0.873 and average absolute error of 33% compared with the actual model with a correlation coefficient of 0.511 and absolute error greater than 250%. We tested different methodologies, but this new one showed dramatically be a promiser way to get better permeability models. The use of the models have had a high impact in the explanation of well performance and workovers, and reservoir simulation models. (author)

  16. Reservoir management under geological uncertainty using fast model update

    NARCIS (Netherlands)

    Hanea, R.; Evensen, G.; Hustoft, L.; Ek, T.; Chitu, A.; Wilschut, F.

    2015-01-01

    Statoil is implementing "Fast Model Update (FMU)," an integrated and automated workflow for reservoir modeling and characterization. FMU connects all steps and disciplines from seismic depth conversion to prediction and reservoir management taking into account relevant reservoir uncertainty. FMU

  17. Characterization of oil and gas reservoir heterogeneity

    Energy Technology Data Exchange (ETDEWEB)

    1991-01-01

    The objective of the cooperative research program is to characterize Alaskan reservoirs in terms of their reserves, physical and chemical properties, geologic configuration and structure, and the development potential. The tasks completed during this period include: (1) geologic reservoir description of Endicott Field; (2) petrographic characterization of core samples taken from selected stratigraphic horizons of the West Sak and Ugnu (Brookian) wells; (3) development of a polydispersed thermodynamic model for predicting asphaltene equilibria and asphaltene precipitation from crude oil-solvent mixtures, and (4) preliminary geologic description of the Milne Point Unit.

  18. The role of reservoir characterization in the reservoir management process (as reflected in the Department of Energy`s reservoir management demonstration program)

    Energy Technology Data Exchange (ETDEWEB)

    Fowler, M.L. [BDM-Petroleum Technologies, Bartlesville, OK (United States); Young, M.A.; Madden, M.P. [BDM-Oklahoma, Bartlesville, OK (United States)] [and others

    1997-08-01

    Optimum reservoir recovery and profitability result from guidance of reservoir practices provided by an effective reservoir management plan. Success in developing the best, most appropriate reservoir management plan requires knowledge and consideration of (1) the reservoir system including rocks, and rock-fluid interactions (i.e., a characterization of the reservoir) as well as wellbores and associated equipment and surface facilities; (2) the technologies available to describe, analyze, and exploit the reservoir; and (3) the business environment under which the plan will be developed and implemented. Reservoir characterization is the essential to gain needed knowledge of the reservoir for reservoir management plan building. Reservoir characterization efforts can be appropriately scaled by considering the reservoir management context under which the plan is being built. Reservoir management plans de-optimize with time as technology and the business environment change or as new reservoir information indicates the reservoir characterization models on which the current plan is based are inadequate. BDM-Oklahoma and the Department of Energy have implemented a program of reservoir management demonstrations to encourage operators with limited resources and experience to learn, implement, and disperse sound reservoir management techniques through cooperative research and development projects whose objectives are to develop reservoir management plans. In each of the three projects currently underway, careful attention to reservoir management context assures a reservoir characterization approach that is sufficient, but not in excess of what is necessary, to devise and implement an effective reservoir management plan.

  19. Reservoir characterization and enhanced oil recovery research

    Energy Technology Data Exchange (ETDEWEB)

    Lake, L.W.; Pope, G.A.; Schechter, R.S.

    1992-03-01

    The research in this annual report falls into three tasks each dealing with a different aspect of enhanced oil recovery. The first task strives to develop procedures for accurately modeling reservoirs for use as input to numerical simulation flow models. This action describes how we have used a detail characterization of an outcrop to provide insights into what features are important to fluid flow modeling. The second task deals with scaling-up and modeling chemical and solvent EOR processes. In a sense this task is the natural extension of task 1 and, in fact, one of the subtasks uses many of the same statistical procedures for insight into the effects of viscous fingering and heterogeneity. The final task involves surfactants and their interactions with carbon dioxide and reservoir minerals. This research deals primarily with phenomena observed when aqueous surfactant solutions are injected into oil reservoirs.

  20. Geothermal Project Den Haag - 3-D models for temperature prediction and reservoir characterization

    Science.gov (United States)

    Mottaghy, D.; Pechnig, R.; Willemsen, G.; Simmelink, H. J.; Vandeweijer, V.

    2009-04-01

    In the framework of the "Den Haag Zuidwest" geothermal district heating system a deep geothermal installation is projected. The target horizon of the planned doublet is the "Delft sandstone" which has been extensively explored for oil- and gas reservoirs in the last century. In the target area, this upper Jurassic sandstone layer is found at a depth of about 2300 m with an average thickness of about 50 m. The study presented here focuses on the prediction of reservoir temperatures and production behavior which is crucial for planning a deep geothermal installation. In the first phase, the main objective was to find out whether there is a significant influence of the 3-dimensional structures of anticlines and synclines on the temperature field, which could cause formation temperatures deviating from the predicted extrapolated temperature data from oil and gas exploration wells. To this end a regional model was set up as a basis for steady state numerical simulations. Since representative input parameters are decisive for reliable model results, all available information was compiled: a) the subsurface geometry, depth and thickness of the stratigraphic layers known from seismic data sets 2) borehole geophysical data and c) geological and petrographical information from exploration wells. In addition 50 cuttings samples were taken from two selected key wells in order to provide direct information on thermal properties of the underlying strata. Thermal conductivity and rock matrix density were measured in the laboratory. These data were combined with a petrophysical log analysis (Gamma Ray, Sonic, Density and Resistivity), which resulted in continuous profiles of porosity, effective thermal conductivity and radiogenetic heat production. These profiles allowed to asses in detail the variability of the petrophysical properties with depth and to check for lateral changes between the wells. All this data entered the numerical simulations which were performed by a 3-D

  1. 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

  2. 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.

  3. Reservoir resistivity characterization incorporating flow dynamics

    KAUST Repository

    Arango, Santiago

    2016-04-07

    Systems and methods for reservoir resistivity characterization are provided, in various aspects, an integrated framework for the estimation of Archie\\'s parameters for a strongly heterogeneous reservoir utilizing the dynamics of the reservoir are provided. The framework can encompass a Bayesian estimation/inversion method for estimating the reservoir parameters, integrating production and time lapse formation conductivity data to achieve a better understanding of the subsurface rock conductivity properties and hence improve water saturation imaging.

  4. An Intelligent Systems Approach to Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Shahab D. Mohaghegh; Jaime Toro; Thomas H. Wilson; Emre Artun; Alejandro Sanchez; Sandeep Pyakurel

    2005-08-01

    Today, the major challenge in reservoir characterization is integrating data coming from different sources in varying scales, in order to obtain an accurate and high-resolution reservoir model. The role of seismic data in this integration is often limited to providing a structural model for the reservoir. Its relatively low resolution usually limits its further use. However, its areal coverage and availability suggest that it has the potential of providing valuable data for more detailed reservoir characterization studies through the process of seismic inversion. In this paper, a novel intelligent seismic inversion methodology is presented to achieve a desirable correlation between relatively low-frequency seismic signals, and the much higher frequency wireline-log data. Vertical seismic profile (VSP) is used as an intermediate step between the well logs and the surface seismic. A synthetic seismic model is developed by using real data and seismic interpretation. In the example presented here, the model represents the Atoka and Morrow formations, and the overlying Pennsylvanian sequence of the Buffalo Valley Field in New Mexico. Generalized regression neural network (GRNN) is used to build two independent correlation models between; (1) Surface seismic and VSP, (2) VSP and well logs. After generating virtual VSP's from the surface seismic, well logs are predicted by using the correlation between VSP and well logs. The values of the density log, which is a surrogate for reservoir porosity, are predicted for each seismic trace through the seismic line with a classification approach having a correlation coefficient of 0.81. The same methodology is then applied to real data taken from the Buffalo Valley Field, to predict inter-well gamma ray and neutron porosity logs through the seismic line of interest. The same procedure can be applied to a complete 3D seismic block to obtain 3D distributions of reservoir properties with less uncertainty than the geostatistical

  5. 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,

  6. Reservoir characterization of Pennsylvanian Sandstone Reservoirs. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, M.

    1992-09-01

    This annual report describes the progress during the second year of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description and scale-up procedures; (ii) outcrop investigation; (iii) in-fill drilling potential. The first section describes the methods by which a reservoir can be characterized, can be described in three dimensions, and can be scaled up with respect to its properties, appropriate for simulation purposes. The second section describes the progress on investigation of an outcrop. The outcrop is an analog of Bartlesville Sandstone. We have drilled ten wells behind the outcrop and collected extensive log and core data. The cores have been slabbed, photographed and the several plugs have been taken. In addition, minipermeameter is used to measure permeabilities on the core surface at six inch intervals. The plugs have been analyzed for the permeability and porosity values. The variations in property values will be tied to the geological descriptions as well as the subsurface data collected from the Glen Pool field. The third section discusses the application of geostatistical techniques to infer in-fill well locations. The geostatistical technique used is the simulated annealing technique because of its flexibility. One of the important reservoir data is the production data. Use of production data will allow us to define the reservoir continuities, which may in turn, determine the in-fill well locations. The proposed technique allows us to incorporate some of the production data as constraints in the reservoir descriptions. The technique has been validated by comparing the results with numerical simulations.

  7. SEISMIC DETERMINATION OF RESERVOIR HETEROGENEITY; APPLICATION TO THE CHARACTERIZATION OF HEAVY OIL RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Matthias G. Imhof; James W. Castle

    2003-11-01

    The objective of the project is to examine how seismic and geologic data can be used to improve characterization of small-scale heterogeneity and their parameterization in reservoir models. The study is performed at West Coalinga Field in California. We continued our investigation on the nature of seismic reactions from heterogeneous reservoirs. We began testing our algorithm to infer parameters of object-based reservoir models from seismic data. We began integration of seismic and geologic data to determine the deterministic limits of conventional seismic data interpretation. Lastly, we began integration of seismic and geologic heterogeneity using stochastic models conditioned both on wireline and seismic data.

  8. Characterization of the infectious reservoir of malaria with an agent-based model calibrated to age-stratified parasite densities and infectiousness.

    Science.gov (United States)

    Gerardin, Jaline; Ouédraogo, André Lin; McCarthy, Kevin A; Eckhoff, Philip A; Wenger, Edward A

    2015-06-03

    Elimination of malaria can only be achieved through removal of all vectors or complete depletion of the infectious reservoir in humans. Mechanistic models can be built to synthesize diverse observations from the field collected under a variety of conditions and subsequently used to query the infectious reservoir in great detail. The EMOD model of malaria transmission was calibrated to prevalence, incidence, asexual parasite density, gametocyte density, infection duration, and infectiousness data from nine study sites. The infectious reservoir was characterized by age and parasite detectability with diagnostics of varying sensitivity over a range of transmission intensities with and without case management and vector control. Mass screen-and-treat drug campaigns were tested for likelihood of achieving elimination. The composition of the infectious reservoir is similar over a range of transmission intensities, and higher intensity settings are biased towards infections in children. Recent ramp-ups in case management and use of insecticide-treated bed nets (ITNs) reduce the infectious reservoir and shift the composition towards sub-microscopic infections. Mass campaigns with anti-malarial drugs are highly effective at interrupting transmission if deployed shortly after ITN campaigns. Low-density infections comprise a substantial portion of the infectious reservoir. Proper timing of vector control, seasonal variation in transmission intensity and mass drug campaigns allows lingering population immunity to help drive a region towards elimination.

  9. Characterization and 3D reservoir modelling of fluvial sandstones of the Williams Fork Formation, Rulison Field, Piceance Basin, Colorado, USA

    International Nuclear Information System (INIS)

    Pranter, Matthew J; Vargas, Marielis F; Davis, Thomas L

    2008-01-01

    This study describes the stratigraphic characteristics and distribution of fluvial deposits of the Upper Cretaceous Williams Fork Formation in a portion of Rulison Field and addresses 3D geologic modelling of reservoir sand bodies and their associated connectivity. Fluvial deposits include isolated and stacked point-bar deposits, crevasse splays and overbank (floodplain) mudrock. Within the Williams Fork Formation, the distribution and connectivity of fluvial sandstones significantly impact reservoir productivity and ultimate recovery. The reservoir sandstones are primarily fluvial point-bar deposits interbedded with shales and coals. Because of the lenticular geometry and limited lateral extent of the reservoir sandstones (common apparent widths of ∼500–1000 ft; ∼150–300 m), relatively high well densities (e.g. 10 acre (660 ft; 200 m) spacing) are often required to deplete the reservoir. Heterogeneity of these fluvial deposits includes larger scale stratigraphic variability associated with vertical stacking patterns and structural heterogeneities associated with faults that exhibit lateral and reverse offsets. The discontinuous character of the fluvial sandstones and lack of distinct marker beds in the middle and upper parts of the Williams Fork Formation make correlation between wells tenuous, even at a 10 acre well spacing. Some intervals of thicker and amalgamated sandstones within the middle and upper Williams Fork Formation can be correlated across greater distances. To aid correlation and for 3D reservoir modelling, vertical lithology proportion curves were used to estimate stratigraphic trends and define the stratigraphic zonation within the reservoir interval. Object-based and indicator-based modelling methods have been applied to the same data and results from the models were compared. Results from the 3D modelling indicate that sandstone connectivity increases with net-to-gross ratio and, at lower net-to-gross ratios (<30%), differences exist in

  10. Modeling infiltration process of regulating reservoir built for flood-control based on site-characterization using GPR

    Science.gov (United States)

    Kuroda, S.; Tatsuya, S.; Sudani, G.; Ikeda, S.; Satoshi, T.; Kenichi, W.; Tagashira, H.; Masukawa, S.

    2013-12-01

    The regulating reservoir built for flood-control in the Shougawa alluvial fan of Toyama prefecture, Japan, was designed to have a high permeable bottom to maintain smooth infiltration of flood water pouring from a river. The infiltration process in the permeable ground was surveyed by sensors, such as piezometers set inside the observation boreholes installed in the reservoir. The observation showed that not only the temperature of the water but also the existence of pore air and heterogeneity in the ground essentially effects on the infiltration behavior beneath the reservoir. To clarify this infiltration process, we conducted 3D-Ground penetrating radar (GPR) survey and time-lapsed cross-borehole radar profiling. 3D-GPR was applicable to detecte less permeable zone with rich clay in sand gravel basement, which control infiltration of reservoir. Time-lapsed cross-borehole radar profiling could estimate infiltration rate in vadose zone. Based on these results we built unsaturated-saturated water flow model considering subsurface heterogeneity and its effect. This model will contribute the management to maintain its permeability and help understanding the effect of reservoir on surrounding water environment. This work was supported by JSPS KAKENHI Grant Numbers 25294117 and 30343768.

  11. INCREASING WATERFLOOD RESERVES IN THE WILMINGTON OIL FIELD THROUGH IMPROVED RESERVOIR CHARACTERIZATION AND RESERVOIR MANAGEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Scott Walker; Chris Phillips; Roy Koerner; Don Clarke; Dan Moos; Kwasi Tagbor

    2002-02-28

    This project increased recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs. Transferring technology so that it can be applied in other sections of the Wilmington Field and by operators in other slope and basin reservoirs is a primary component of the project. This project used advanced reservoir characterization tools, including the pulsed acoustic cased-hole logging tool, geologic three-dimensional (3-D) modeling software, and commercially available reservoir management software to identify sands with remaining high oil saturation following waterflood. Production from the identified high oil saturated sands was stimulated by recompleting existing production and injection wells in these sands using conventional means as well as a short radius redrill candidate. Although these reservoirs have been waterflooded over 40 years, researchers have found areas of remaining oil saturation. Areas such as the top sand in the Upper Terminal Zone Fault Block V, the western fault slivers of Upper Terminal Zone Fault Block V, the bottom sands of the Tar Zone Fault Block V, and the eastern edge of Fault Block IV in both the Upper Terminal and Lower Terminal Zones all show significant remaining oil saturation. Each area of interest was uncovered emphasizing a different type of reservoir characterization technique or practice. This was not the original strategy but was necessitated by the different levels of progress in each of the project activities.

  12. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    Energy Technology Data Exchange (ETDEWEB)

    P. K. Pande

    1998-10-29

    Initial drilling of wells on a uniform spacing, without regard to reservoir performance and characterization, must become a process of the past. Such efforts do not optimize reservoir development as they fail to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. These reservoirs are typically characterized by: o Large, discontinuous pay intervals o Vertical and lateral changes in reservoir properties o Low reservoir energy o High residual oil saturation o Low recovery efficiency

  13. Reservoir Identification: Parameter Characterization or Feature Classification

    Science.gov (United States)

    Cao, J.

    2017-12-01

    The ultimate goal of oil and gas exploration is to find the oil or gas reservoirs with industrial mining value. Therefore, the core task of modern oil and gas exploration is to identify oil or gas reservoirs on the seismic profiles. Traditionally, the reservoir is identify by seismic inversion of a series of physical parameters such as porosity, saturation, permeability, formation pressure, and so on. Due to the heterogeneity of the geological medium, the approximation of the inversion model and the incompleteness and noisy of the data, the inversion results are highly uncertain and must be calibrated or corrected with well data. In areas where there are few wells or no well, reservoir identification based on seismic inversion is high-risk. Reservoir identification is essentially a classification issue. In the identification process, the underground rocks are divided into reservoirs with industrial mining value and host rocks with non-industrial mining value. In addition to the traditional physical parameters classification, the classification may be achieved using one or a few comprehensive features. By introducing the concept of seismic-print, we have developed a new reservoir identification method based on seismic-print analysis. Furthermore, we explore the possibility to use deep leaning to discover the seismic-print characteristics of oil and gas reservoirs. Preliminary experiments have shown that the deep learning of seismic data could distinguish gas reservoirs from host rocks. The combination of both seismic-print analysis and seismic deep learning is expected to be a more robust reservoir identification method. The work was supported by NSFC under grant No. 41430323 and No. U1562219, and the National Key Research and Development Program under Grant No. 2016YFC0601

  14. Multi-Objective History Matching with a Proxy Model for the Characterization of Production Performances at the Shale Gas Reservoir

    Directory of Open Access Journals (Sweden)

    Jaejun Kim

    2017-04-01

    Full Text Available This paper presents a fast, reliable multi-objective history-matching method based on proxy modeling to forecast the production performances of shale gas reservoirs for which all available post-hydraulic-fracturing production data, i.e., the daily gas rate and cumulative-production volume until the given date, are honored. The developed workflow consists of distance-based generalized sensitivity analysis (DGSA to determine the spatiotemporal-parameter significance, fast marching method (FMM as a proxy model, and a multi-objective evolutionary algorithm to integrate the dynamic data. The model validation confirms that the FMM is a sound surrogate model working within an error of approximately 2% for the estimated ultimate recovery (EUR, and it is 11 times faster than a full-reservoir simulation. The predictive accuracy on future production after matching 1.5-year production histories is assessed to examine the applicability of the proposed method. The DGSA determines the effective parameters with respect to the gas rate and the cumulative volume, including fracture permeability, fracture half-length, enhanced permeability in the stimulated reservoir volume, and average post-fracturing porosity. A comparison of the prediction accuracy for single-objective optimization shows that the proposed method accurately estimates the recoverable volume as well as the production profiles to within an error of 0.5%, while the single-objective consideration reveals the scale-dependency problem with lesser accuracy. The results of this study are useful to overcome the time-consuming effort of using a multi-objective evolutionary algorithm and full-scale reservoir simulation as well as to conduct a more-realistic prediction of the shale gas reserves and the corresponding production performances.

  15. Fracture characterization in a deep geothermal reservoir

    Science.gov (United States)

    Rühaak, Wolfram; Hehn, Vera; Hassanzadegan, Alireza; Tischner, Torsten

    2017-04-01

    At the geothermal research drilling Horstberg in North West Germany studies for the characterization of a vertical fracture are performed. The fracture was created by a massive hydraulic stimulation in 2003 in approx. 3700 m depth within rocks of the middle Buntsandstein. The fracture surface is in the order of 100,000 m2, depending on the flow rate at which water is injected. Besides hydraulic characterization, multiple tracer tests are planned. At the depth of interest the reservoir temperature is around 150 °C, pressure is around 600 bar (60 MPa) and due to salinity the water density is around 1200 kg/m3. Knowledge of tracer stability and behavior at these reservoir conditions is limited. Additionally, the planned tracer tests will be performed within one single borehole. In a closed cycle water is injected into the inner pipe of the well (tubing), which is separated by a permanent packer from the outer pipe (annulus). The water is produced back from the annulus approximately 150 m above the injection point. Thus, the circulation of thermal water between two sandstone layers via an artificial fracture can be achieved. Tests will be carried out with different flow rates and accordingly with different pressures, resulting in different fracture areas. Due to this test setup tracer signals will be stacked and will remain for a longer time in the fracture - which is the reason why different tracers are required. For an optimal characterization both conservative and reactive tracers will be used and different injection methods (continuous, instantaneous and pulsed) will be applied. For a proper setup of the tracer test numerical modelling studies are performed in advance. The relevant thermal, hydraulic and chemical processes (mainly adsorption and degredation) are coupled, resulting in a THC model; additionally the dependence of fracture aperture and area on fluid pressure has to be considered. Instead of applying a mechanically coupled model (THMC) a simplified

  16. An Effective Reservoir Parameter for Seismic Characterization of Organic Shale Reservoir

    Science.gov (United States)

    Zhao, Luanxiao; Qin, Xuan; Zhang, Jinqiang; Liu, Xiwu; Han, De-hua; Geng, Jianhua; Xiong, Yineng

    2017-12-01

    Sweet spots identification for unconventional shale reservoirs involves detection of organic-rich zones with abundant porosity. However, commonly used elastic attributes, such as P- and S-impedances, often show poor correlations with porosity and organic matter content separately and thus make the seismic characterization of sweet spots challenging. Based on an extensive analysis of worldwide laboratory database of core measurements, we find that P- and S-impedances exhibit much improved linear correlations with the sum of volume fraction of organic matter and porosity than the single parameter of organic matter volume fraction or porosity. Importantly, from the geological perspective, porosity in conjunction with organic matter content is also directly indicative of the total hydrocarbon content of shale resources plays. Consequently, we propose an effective reservoir parameter (ERP), the sum of volume fraction of organic matter and porosity, to bridge the gap between hydrocarbon accumulation and seismic measurements in organic shale reservoirs. ERP acts as the first-order factor in controlling the elastic properties as well as characterizing the hydrocarbon storage capacity of organic shale reservoirs. We also use rock physics modeling to demonstrate why there exists an improved linear correlation between elastic impedances and ERP. A case study in a shale gas reservoir illustrates that seismic-derived ERP can be effectively used to characterize the total gas content in place, which is also confirmed by the production well.

  17. SEISMIC DETERMINATION OF RESERVOIR HETEROGENEITY: APPLICATION TO THE CHARACTERIZATION OF HEAVY OIL RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Matthias G. Imhof; James W. Castle

    2005-02-01

    The objective of the project was to examine how seismic and geologic data can be used to improve characterization of small-scale heterogeneity and their parameterization in reservoir models. The study focused on West Coalinga Field in California. The project initially attempted to build reservoir models based on different geologic and geophysical data independently using different tools, then to compare the results, and ultimately to integrate them all. We learned, however, that this strategy was impractical. The different data and tools need to be integrated from the beginning because they are all interrelated. This report describes a new approach to geostatistical modeling and presents an integration of geology and geophysics to explain the formation of the complex Coalinga reservoir.

  18. Multiscale Fractal Characterization of Hierarchical Heterogeneity in Sandstone Reservoirs

    Science.gov (United States)

    Liu, Yanfeng; Liu, Yuetian; Sun, Lu; Liu, Jian

    2016-07-01

    Heterogeneities affecting reservoirs often develop at different scales. Previous studies have described these heterogeneities using different parameters depending on their size, and there is no one comprehensive method of reservoir evaluation that considers every scale. This paper introduces a multiscale fractal approach to quantify consistently the hierarchical heterogeneities of sandstone reservoirs. Materials taken from typical depositional pattern and aerial photography are used to represent three main types of sandstone reservoir: turbidite, braided, and meandering river system. Subsequent multiscale fractal dimension analysis using the Bouligand-Minkowski method characterizes well the hierarchical heterogeneity of the sandstone reservoirs. The multiscale fractal dimension provides a curve function that describes the heterogeneity at different scales. The heterogeneity of a reservoir’s internal structure decreases as the observational scale increases. The shape of a deposit’s facies is vital for quantitative determination of the sedimentation type, and thus enhanced oil recovery. Characterization of hierarchical heterogeneity by multiscale fractal dimension can assist reservoir evaluation, geological modeling, and even the design of well patterns.

  19. Advantageous Reservoir Characterization Technology in Extra Low Permeability Oil Reservoirs

    Directory of Open Access Journals (Sweden)

    Yutian Luo

    2017-01-01

    Full Text Available This paper took extra low permeability reservoirs in Dagang Liujianfang Oilfield as an example and analyzed different types of microscopic pore structures by SEM, casting thin sections fluorescence microscope, and so on. With adoption of rate-controlled mercury penetration, NMR, and some other advanced techniques, based on evaluation parameters, namely, throat radius, volume percentage of mobile fluid, start-up pressure gradient, and clay content, the classification and assessment method of extra low permeability reservoirs was improved and the parameter boundaries of the advantageous reservoirs were established. The physical properties of reservoirs with different depth are different. Clay mineral variation range is 7.0%, and throat radius variation range is 1.81 μm, and start pressure gradient range is 0.23 MPa/m, and movable fluid percentage change range is 17.4%. The class IV reservoirs account for 9.56%, class II reservoirs account for 12.16%, and class III reservoirs account for 78.29%. According to the comparison of different development methods, class II reservoir is most suitable for waterflooding development, and class IV reservoir is most suitable for gas injection development. Taking into account the gas injection in the upper section of the reservoir, the next section of water injection development will achieve the best results.

  20. Petroleum reservoir data for testing simulation models

    Energy Technology Data Exchange (ETDEWEB)

    Lloyd, J.M.; Harrison, W.

    1980-09-01

    This report consists of reservoir pressure and production data for 25 petroleum reservoirs. Included are 5 data sets for single-phase (liquid) reservoirs, 1 data set for a single-phase (liquid) reservoir with pressure maintenance, 13 data sets for two-phase (liquid/gas) reservoirs and 6 for two-phase reservoirs with pressure maintenance. Also given are ancillary data for each reservoir that could be of value in the development and validation of simulation models. A bibliography is included that lists the publications from which the data were obtained.

  1. Exploration and reservoir characterization; Technology Target Areas; TTA2 - Exploration and reservoir characterisation

    Energy Technology Data Exchange (ETDEWEB)

    2008-07-01

    In future, research within exploration and reservoir characterization will play an even more important role for Norway since resources are decreasing and new challenges like deep sea, harsh environment and last but not least environmental issues have to be considered. There are two major fields which have to be addressed within exploration and reservoir characterization: First, replacement of reserves by new discoveries and ultimate field recoveries in mature basins at the Norwegian Continental shelf, e.g. at the Halten Terrace has to be addressed. A wealth of data exists in the more mature areas. Interdisciplinary integration is a key feature of reservoir characterization, where available data and specialist knowledge need to be combined into a consistent reservoir description. A systematic approach for handling both uncertainties in data sources and uncertainties in basic models is needed. Fast simulation techniques are necessary to generate models spanning the event space, covering both underground based and model-based uncertainties. Second, exploration in frontier areas like the Barents Sea region and the deeper Voering Basin has to be addressed. The scarcity of wells in these frontier areas leads to uncertainties in the geological understanding. Basin- and depositional modelling are essential for predicting where source rocks and reservoir rocks are deposited, and if, when and which hydrocarbons are generated and trapped. Predictive models and improved process understanding is therefore crucial to meet these issues. Especially the challenges related to the salt deposits e.g. sub-salt/sub-basalt reservoir definitions in the Nordkapp Basin demands up-front research and technology developments. TTA2 stresses the need to focus on the development of new talents. We also see a strong need to push cooperation as far as possible in the present competitive environment. Projects that may require a substantial financial commitment have been identified. The following

  2. Unconventional Tight Reservoirs Characterization with Nuclear Magnetic Resonance

    Science.gov (United States)

    Santiago, C. J. S.; Solatpour, R.; Kantzas, A.

    2017-12-01

    The increase in tight reservoir exploitation projects causes producing many papers each year on new, modern, and modified methods and techniques on estimating characteristics of these reservoirs. The most ambiguous of all basic reservoir property estimations deals with permeability. One of the logging methods that is advertised to predict permeability but is always met by skepticism is Nuclear Magnetic Resonance (NMR). The ability of NMR to differentiate between bound and movable fluids and providing porosity increased the capability of NMR as a permeability prediction technique. This leads to a multitude of publications and the motivation of a review paper on this subject by Babadagli et al. (2002). The first part of this presentation is dedicated to an extensive review of the existing correlation models for NMR based estimates of tight reservoir permeability to update this topic. On the second part, the collected literature information is used to analyze new experimental data. The data are collected from tight reservoirs from Canada, the Middle East, and China. A case study is created to apply NMR measurement in the prediction of reservoir characterization parameters such as porosity, permeability, cut-offs, irreducible saturations etc. Moreover, permeability correlations are utilized to predict permeability. NMR experiments were conducted on water saturated cores. NMR T2 relaxation times were measured. NMR porosity, the geometric mean relaxation time (T2gm), Irreducible Bulk Volume (BVI), and Movable Bulk Volume (BVM) were calculated. The correlation coefficients were computed based on multiple regression analysis. Results are cross plots of NMR permeability versus the independently measured Klinkenberg corrected permeability. More complicated equations are discussed. Error analysis of models is presented and compared. This presentation is beneficial in understanding existing tight reservoir permeability models. The results can be used as a guide for choosing

  3. A reservoir simulation approach for modeling of naturally fractured reservoirs

    Directory of Open Access Journals (Sweden)

    H. Mohammadi

    2012-12-01

    Full Text Available In this investigation, the Warren and Root model proposed for the simulation of naturally fractured reservoir was improved. A reservoir simulation approach was used to develop a 2D model of a synthetic oil reservoir. Main rock properties of each gridblock were defined for two different types of gridblocks called matrix and fracture gridblocks. These two gridblocks were different in porosity and permeability values which were higher for fracture gridblocks compared to the matrix gridblocks. This model was solved using the implicit finite difference method. Results showed an improvement in the Warren and Root model especially in region 2 of the semilog plot of pressure drop versus time, which indicated a linear transition zone with no inflection point as predicted by other investigators. Effects of fracture spacing, fracture permeability, fracture porosity, matrix permeability and matrix porosity on the behavior of a typical naturally fractured reservoir were also presented.

  4. Full Waveform Inversion for Reservoir Characterization - A Synthetic Study

    KAUST Repository

    Zabihi Naeini, E.

    2017-05-26

    Most current reservoir-characterization workflows are based on classic amplitude-variation-with-offset (AVO) inversion techniques. Although these methods have generally served us well over the years, here we examine full-waveform inversion (FWI) as an alternative tool for higher-resolution reservoir characterization. An important step in developing reservoir-oriented FWI is the implementation of facies-based rock physics constraints adapted from the classic methods. We show that such constraints can be incorporated into FWI by adding appropriately designed regularization terms to the objective function. The advantages of the proposed algorithm are demonstrated on both isotropic and VTI (transversely isotropic with a vertical symmetry axis) models with pronounced lateral and vertical heterogeneity. The inversion results are explained using the theoretical radiation patterns produced by perturbations in the medium parameters.

  5. Reservoir Model Information System: REMIS

    Science.gov (United States)

    Lee, Sang Yun; Lee, Kwang-Wu; Rhee, Taehyun; Neumann, Ulrich

    2009-01-01

    We describe a novel data visualization framework named Reservoir Model Information System (REMIS) for the display of complex and multi-dimensional data sets in oil reservoirs. It is aimed at facilitating visual exploration and analysis of data sets as well as user collaboration in an easier way. Our framework consists of two main modules: the data access point module and the data visualization module. For the data access point module, the Phrase-Driven Grammar System (PDGS) is adopted for helping users facilitate the visualization of data. It integrates data source applications and external visualization tools and allows users to formulate data query and visualization descriptions by selecting graphical icons in a menu or on a map with step-by-step visual guidance. For the data visualization module, we implemented our first prototype of an interactive volume viewer named REMVR to classify and to visualize geo-spatial specific data sets. By combining PDGS and REMVR, REMIS assists users better in describing visualizations and exploring data so that they can easily find desired data and explore interesting or meaningful relationships including trends and exceptions in oil reservoir model data.

  6. An Intelligent Systems Approach to Reservoir Characterization. Final Report

    International Nuclear Information System (INIS)

    Shahab D. Mohaghegh; Jaime Toro; Thomas H. Wilson; Emre Artun; Alejandro Sanchez; Sandeep Pyakurel

    2005-01-01

    Today, the major challenge in reservoir characterization is integrating data coming from different sources in varying scales, in order to obtain an accurate and high-resolution reservoir model. The role of seismic data in this integration is often limited to providing a structural model for the reservoir. Its relatively low resolution usually limits its further use. However, its areal coverage and availability suggest that it has the potential of providing valuable data for more detailed reservoir characterization studies through the process of seismic inversion. In this paper, a novel intelligent seismic inversion methodology is presented to achieve a desirable correlation between relatively low-frequency seismic signals, and the much higher frequency wireline-log data. Vertical seismic profile (VSP) is used as an intermediate step between the well logs and the surface seismic. A synthetic seismic model is developed by using real data and seismic interpretation. In the example presented here, the model represents the Atoka and Morrow formations, and the overlying Pennsylvanian sequence of the Buffalo Valley Field in New Mexico. Generalized regression neural network (GRNN) is used to build two independent correlation models between; (1) Surface seismic and VSP, (2) VSP and well logs. After generating virtual VSP's from the surface seismic, well logs are predicted by using the correlation between VSP and well logs. The values of the density log, which is a surrogate for reservoir porosity, are predicted for each seismic trace through the seismic line with a classification approach having a correlation coefficient of 0.81. The same methodology is then applied to real data taken from the Buffalo Valley Field, to predict inter-well gamma ray and neutron porosity logs through the seismic line of interest. The same procedure can be applied to a complete 3D seismic block to obtain 3D distributions of reservoir properties with less uncertainty than the geostatistical

  7. Increasing Waterflooding Reservoirs in the Wilmington Oil Field through Improved Reservoir Characterization and Reservoir Management, Class III

    Energy Technology Data Exchange (ETDEWEB)

    Koerner, Roy; Clarke, Don; Walker, Scott; Phillips, Chris; Nguyen, John; Moos, Dan; Tagbor, Kwasi

    2001-08-07

    This project was intended to increase recoverable waterflood reserves in slope and basin reservoirs through improved reservoir characterization and reservoir management. The particular application of this project is in portions of Fault Blocks IV and V of the Wilmington Oil Field, in Long Beach, California, but the approach is widely applicable in slope and basin reservoirs, transferring technology so that it can be applied in other sections of the Wilmington field and by operators in other slope and basin reservoirs is a primary component of the project.

  8. Gypsy Field project in reservoir characterization

    Energy Technology Data Exchange (ETDEWEB)

    Castagna, John P.; Jr., O' Meara, Daniel J.

    2000-01-12

    The overall objective of this project was to use extensive Gypsy Field Laboratory and data as a focus for developing and testing reservoir characterization methods that are targeted at improved recovery of conventional oil. This report describes progress since project report DOE/BC/14970-7 and covers the period June 1997-September 1998 and represents one year of funding originally allocated for the year 1996. During the course of the work previously performed, high resolution geophysical and outcrop data revealed the importance of fractures at the Gypsy site. In addition, personnel changes and alternative funding (OCAST and oil company support of various kinds) allowed the authors to leverage DOE contributions and focus more on geophysical characterization.

  9. A hybrid framework for reservoir characterization using fuzzy ranking and an artificial neural network

    Science.gov (United States)

    Wang, Baijie; Wang, Xin; Chen, Zhangxin

    2013-08-01

    Reservoir characterization refers to the process of quantitatively assigning reservoir properties using all available field data. Artificial neural networks (ANN) have recently been introduced to solve reservoir characterization problems dealing with the complex underlying relationships inherent in well log data. Despite the utility of ANNs, the current limitation is that most existing applications simply focus on directly implementing existing ANN models instead of improving/customizing them to fit the specific reservoir characterization tasks at hand. In this paper, we propose a novel intelligent framework that integrates fuzzy ranking (FR) and multilayer perceptron (MLP) neural networks for reservoir characterization. FR can automatically identify a minimum subset of well log data as neural inputs, and the MLP is trained to learn the complex correlations from the selected well log data to a target reservoir property. FR guarantees the selection of the optimal subset of representative data from the overall well log data set for the characterization of a specific reservoir property; and, this implicitly improves the modeling and predication accuracy of the MLP. In addition, a growing number of industrial agencies are implementing geographic information systems (GIS) in field data management; and, we have designed the GFAR solution (GIS-based FR ANN Reservoir characterization solution) system, which integrates the proposed framework into a GIS system that provides an efficient characterization solution. Three separate petroleum wells from southwestern Alberta, Canada, were used in the presented case study of reservoir porosity characterization. Our experiments demonstrate that our method can generate reliable results.

  10. 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

  11. Flow-based dissimilarity measures for reservoir models : a spatial-temporal tensor approach

    NARCIS (Netherlands)

    Insuasty, Edwin; van den Hof, P.M.J.; Weiland, Siep; Jansen, J.D.

    2017-01-01

    In reservoir engineering, it is attractive to characterize the difference between reservoir models in metrics that relate to the economic performance of the reservoir as well as to the underlying geological structure. In this paper, we develop a dissimilarity measure that is based on reservoir

  12. Integrated reservoir assessment and characterization: Final report, October 1, 1985--September 30, 1988

    Energy Technology Data Exchange (ETDEWEB)

    Honarpour, M.; Szpakiewicz, M.; Sharma, B.; Chang, Ming-Ming; Schatzinger, R.; Jackson, S.; Tomutsa, L.; Maerefat, N.

    1989-05-01

    This report covers the development of a generic approach to reservoir characterization, the preliminary studies leading to the selection of an appropriate depositional system for detailed study, the application of outcrop studies to quantified reservoir characterization, and the construction of a quantified geological/engineering model used to screen the effects and scales of various geological heterogeneities within a reservoir. These heterogeneities result in large production/residual oil saturation contrasts over small distances. 36 refs., 124 figs., 38 tabs.

  13. Applying a probabilistic seismic-petrophysical inversion and two different rock-physics models for reservoir characterization in offshore Nile Delta

    Science.gov (United States)

    Aleardi, Mattia

    2018-01-01

    We apply a two-step probabilistic seismic-petrophysical inversion for the characterization of a clastic, gas-saturated, reservoir located in offshore Nile Delta. In particular, we discuss and compare the results obtained when two different rock-physics models (RPMs) are employed in the inversion. The first RPM is an empirical, linear model directly derived from the available well log data by means of an optimization procedure. The second RPM is a theoretical, non-linear model based on the Hertz-Mindlin contact theory. The first step of the inversion procedure is a Bayesian linearized amplitude versus angle (AVA) inversion in which the elastic properties, and the associated uncertainties, are inferred from pre-stack seismic data. The estimated elastic properties constitute the input to the second step that is a probabilistic petrophysical inversion in which we account for the noise contaminating the recorded seismic data and the uncertainties affecting both the derived rock-physics models and the estimated elastic parameters. In particular, a Gaussian mixture a-priori distribution is used to properly take into account the facies-dependent behavior of petrophysical properties, related to the different fluid and rock properties of the different litho-fluid classes. In the synthetic and in the field data tests, the very minor differences between the results obtained by employing the two RPMs, and the good match between the estimated properties and well log information, confirm the applicability of the inversion approach and the suitability of the two different RPMs for reservoir characterization in the investigated area.

  14. Reservoir characterization of the Snorre Field

    OpenAIRE

    Gjestvang, Jørgen

    2016-01-01

    Master's thesis in Petroleum engineering The fluvial sandstone in the Snorre field consists of braided to meander streams deposited in arid and in humid climate that show a clear differences in the sedimentology and reservoir properties, especially the silt content in large part of the reservoir which decrease the reservoir properties and water saturation. The heterogeneity of these fluvial formations combined with the faulting history makes this reservoir highly complex with many local an...

  15. Reactive Tracers for Characterizing Fractured Geothermal Reservoirs

    Science.gov (United States)

    Hawkins, Adam J.

    Multi-component tracer tests were conducted at a 10 x 10 m well field located in the Altona Flat Rocks of northern New York. Temperature advancement between two wells separated by 14 m was monitored throughout the well field during progressive heating of the reservoir over 6 d. Multiple approaches to predicting heat transport were applied to field data and compared to temperature rise recorded during reservoir heat-up. Tracer analysis incorporated both an analytical one-dimensional model and a two-dimensional numerical model for non-uniform fractures experiencing "flow-channeling." Modeling efforts demonstrated that estimating heat transfer surface area using a combined inert/adsorbing tracer (cesium-iodide) could provide accurate forecasting of premature thermal breakthrough. In addition, thermally degrading tracer tests were used to monitor inter-well temperature during progressive reservoir heating. Inert tracers alone were, in general, inadequate in forecasting thermal performance. In fact, moment analysis shows that, mathematically, thermal breakthrough is independent of parameters that primarily influence inert tracers. The most accurate prediction of thermal breakthrough using inert tracer alone was produced by treating hydrodynamic dispersion as a truly Fickian process with known and accurate mathematical models. Under this assumption, inert tracer data was matched by solving an inverse problem for non-uniform fracture aperture. Early arrival of the thermal front was predicted at the production, but was less accurate than using a combined inert/adsorbing tracer test. The spatial distribution of fluid flow paths in the plane of the fracture were identified using computational models, Fiber-Optic Distributed Temperature Sensing (FO-DTS), and Ground Penetrating Radar (GPR) imaging of saline tracer flow paths in the target fracture. Without exception, fluid flow was found to be concentrated in a roughly 1 m wide flow channel directly between the two wells. The

  16. Application of integrated reservoir management and reservoir characterization to optimize infill drilling, Class II

    Energy Technology Data Exchange (ETDEWEB)

    Bergeron, Jack; Blasingame, Tom; Doublet, Louis; Kelkar, Mohan; Freeman, George; Callard, Jeff; Moore, David; Davies, David; Vessell, Richard; Pregger, Brian; Dixon, Bill; Bezant, Bryce

    2000-03-16

    The major purpose of this project was to demonstrate the use of cost effective reservoir characterization and management tools that will be helpful to both independent and major operators for the optimal development of heterogeneous, low permeability carbonate reservoirs such as the North Robertson (Clearfork) Unit.

  17. Calibration of Seismic Attributes for Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Wayne D. Pennington

    2002-09-29

    The project, "Calibration of Seismic Attributes for Reservoir Characterization," is now complete. Our original proposed scope of work included detailed analysis of seismic and other data from two to three hydrocarbon fields; we have analyzed data from four fields at this level of detail, two additional fields with less detail, and one other 2D seismic line used for experimentation. We also included time-lapse seismic data with ocean-bottom cable recordings in addition to the originally proposed static field data. A large number of publications and presentations have resulted from this work, inlcuding several that are in final stages of preparation or printing; one of these is a chapter on "Reservoir Geophysics" for the new Petroleum Engineering Handbook from the Society of Petroleum Engineers. Major results from this project include a new approach to evaluating seismic attributes in time-lapse monitoring studies, evaluation of pitfalls in the use of point-based measurements and facies classifications, novel applications of inversion results, improved methods of tying seismic data to the wellbore, and a comparison of methods used to detect pressure compartments. Some of the data sets used are in the public domain, allowing other investigators to test our techniques or to improve upon them using the same data. From the public-domain Stratton data set we have demonstrated that an apparent correlation between attributes derived along 'phantom' horizons are artifacts of isopach changes; only if the interpreter understands that the interpretation is based on this correlation with bed thickening or thinning, can reliable interpretations of channel horizons and facies be made. From the public-domain Boonsville data set we developed techniques to use conventional seismic attributes, including seismic facies generated under various neural network procedures, to subdivide regional facies determined from logs into productive and non-productive subfacies, and we

  18. A Statistical Graphical Model of the California Reservoir System

    Science.gov (United States)

    Taeb, A.; Reager, J. T.; Turmon, M.; Chandrasekaran, V.

    2017-11-01

    The recent California drought has highlighted the potential vulnerability of the state's water management infrastructure to multiyear dry intervals. Due to the high complexity of the network, dynamic storage changes in California reservoirs on a state-wide scale have previously been difficult to model using either traditional statistical or physical approaches. Indeed, although there is a significant line of research on exploring models for single (or a small number of) reservoirs, these approaches are not amenable to a system-wide modeling of the California reservoir network due to the spatial and hydrological heterogeneities of the system. In this work, we develop a state-wide statistical graphical model to characterize the dependencies among a collection of 55 major California reservoirs across the state; this model is defined with respect to a graph in which the nodes index reservoirs and the edges specify the relationships or dependencies between reservoirs. We obtain and validate this model in a data-driven manner based on reservoir volumes over the period 2003-2016. A key feature of our framework is a quantification of the effects of external phenomena that influence the entire reservoir network. We further characterize the degree to which physical factors (e.g., state-wide Palmer Drought Severity Index (PDSI), average temperature, snow pack) and economic factors (e.g., consumer price index, number of agricultural workers) explain these external influences. As a consequence of this analysis, we obtain a system-wide health diagnosis of the reservoir network as a function of PDSI.

  19. Advancing reservoir operation description in physically based hydrological models

    Science.gov (United States)

    Anghileri, Daniela; Giudici, Federico; Castelletti, Andrea; Burlando, Paolo

    2016-04-01

    Last decades have seen significant advances in our capacity of characterizing and reproducing hydrological processes within physically based models. Yet, when the human component is considered (e.g. reservoirs, water distribution systems), the associated decisions are generally modeled with very simplistic rules, which might underperform in reproducing the actual operators' behaviour on a daily or sub-daily basis. For example, reservoir operations are usually described by a target-level rule curve, which represents the level that the reservoir should track during normal operating conditions. The associated release decision is determined by the current state of the reservoir relative to the rule curve. This modeling approach can reasonably reproduce the seasonal water volume shift due to reservoir operation. Still, it cannot capture more complex decision making processes in response, e.g., to the fluctuations of energy prices and demands, the temporal unavailability of power plants or varying amount of snow accumulated in the basin. In this work, we link a physically explicit hydrological model with detailed hydropower behavioural models describing the decision making process by the dam operator. In particular, we consider two categories of behavioural models: explicit or rule-based behavioural models, where reservoir operating rules are empirically inferred from observational data, and implicit or optimization based behavioural models, where, following a normative economic approach, the decision maker is represented as a rational agent maximising a utility function. We compare these two alternate modelling approaches on the real-world water system of Lake Como catchment in the Italian Alps. The water system is characterized by the presence of 18 artificial hydropower reservoirs generating almost 13% of the Italian hydropower production. Results show to which extent the hydrological regime in the catchment is affected by different behavioural models and reservoir

  20. Application of integrated reservoir management and reservoir characterization to optimize infill drilling

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-04-01

    This project has used a multi-disciplinary approach employing geology, geophysics, and engineering to conduct advanced reservoir characterization and management activities to design and implement an optimized infill drilling program at the North Robertson (Clearfork) Unit in Gaines County, Texas. The activities during the first Budget Period consisted of developing an integrated reservoir description from geological, engineering, and geostatistical studies, and using this description for reservoir flow simulation. Specific reservoir management activities were identified and tested. The geologically targeted infill drilling program currently being implemented is a result of this work. A significant contribution of this project is to demonstrate the use of cost-effective reservoir characterization and management tools that will be helpful to both independent and major operators for the optimal development of heterogeneous, low permeability shallow-shelf carbonate (SSC) reservoirs. The techniques that are outlined for the formulation of an integrated reservoir description apply to all oil and gas reservoirs, but are specifically tailored for use in the heterogeneous, low permeability carbonate reservoirs of West Texas.

  1. Top-Down, Intelligent Reservoir Model

    Science.gov (United States)

    Mohaghegh, Shahab

    2010-05-01

    Conventional reservoir simulation and modeling is a bottom-up approach. It starts with building a geological model of the reservoir that is populated with the best available petrophysical and geophysical information at the time of development. Engineering fluid flow principles are added and solved numerically so as to arrive at a dynamic reservoir model. The dynamic reservoir model is calibrated using the production history of multiple wells and the history matched model is used to strategize field development in order to improve recovery. Top-Down, Intelligent Reservoir Modeling approaches the reservoir simulation and modeling from an opposite angle by attempting to build a realization of the reservoir starting with the measured well production behavior (history). The production history is augmented by core, log, well test and seismic data in order to increase the accuracy of the Top-Down modeling technique. Although not intended as a substitute for the conventional reservoir simulation of large, complex fields, this novel approach to reservoir modeling can be used as an alternative (at a fraction of the cost) to conventional reservoir simulation and modeling in cases where performing conventional modeling is cost (and man-power) prohibitive. In cases where a conventional model of a reservoir already exists, Top-Down modeling should be considered as a compliment to, rather than a competition for the conventional technique, to provide an independent look at the data coming from the reservoir/wells for optimum development strategy and recovery enhancement. Top-Down, Intelligent Reservoir Modeling starts with well-known reservoir engineering techniques such as Decline Curve Analysis, Type Curve Matching, History Matching using single well numerical reservoir simulation, Volumetric Reserve Estimation and calculation of Recovery Factors for all the wells (individually) in the field. Using statistical techniques multiple Production Indicators (3, 6, and 9 months cum

  2. HIV Reservoir Characterization Symposium: 19 September 2016, Ghent, Belgium.

    Science.gov (United States)

    Malatinkova, Eva; De Spiegelaere, Ward; Vandekerckhove, Linos; Sips, Magdalena

    2017-01-01

    The HIV Cure Research Center (HCRC) in Ghent organised the first HIV Reservoir Characterization Symposium, and brought together virologists, molecular biologists, immunologists and clinicians to discuss the most recent developments in HIV reservoir characterisation with a view to achieving an HIV cure. The one-day symposium covered new developments in the field of HIV reservoir and HIV cure research, with the latest news on the European HIV cure trials. This report summarises the major themes discussed during the symposium.

  3. Modeling Study of High Pressure and High Temperature Reservoir Fluids

    DEFF Research Database (Denmark)

    Varzandeh, Farhad

    S-characterization combinations and 260 reservoir fluids. PC-SAFT with the new general characterization method is shown to give the lowest AAD% and maximum deviation in calculation of saturation pressure, density and STO density, among all the tested characterization methods for PC-SAFT. Application of the new characterization...... be highly rewarding if successfully produced. This PhD project is part of the NextOil (New Extreme Oil and Gas in the Danish North Sea) project which is intended to reduce the uncertainties in HPHT field development. The main focus of this PhD is on accurate description of the reservoir fluid behavior under...... HPHT conditions to minimize the production risks from these types of reservoirs. In particular, the study has thoroughly evaluated several non-cubic Equations of State (EoSs) which are considered promising for HPHT fluid modeling, showing their advantages and short comings based on an extensive...

  4. Volume 4: Characterization of representative reservoirs -- Gulf of Mexico field, U-8 reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Koperna, G.J. Jr.; Johnson, H.R. [BDM Federal, Inc., McLean, VA (United States); Salamy, S.P.; Reeves, T.K. [BDM-Oklahoma, Inc., Bartlesville, OK (United States); Sawyer, W.K. [Mathematical and Computer Services, Inc., Danville, VA (United States); Kimbrell, W.C.; Schenewerk, P.A. [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Petroleum Engineering

    1998-07-01

    A reservoir study was performed using a publicly available black oil simulator to history match and predict the performance of a Gulf of Mexico reservoir. The first objective of this simulation study was to validate the Black Oil Applied Simulation Tool version three for personal computers (BOAST3-PC) model to ensure the integrity of the simulation runs. Once validation was completed, a field history match for the Gulf of Mexico U-8 oil reservoir was attempted. A verbal agreement was reached with the operator of this reservoir to blindcode the name and location of the reservoir. In return, the operator supplied data and assistance in regards to the technical aspects of the research. On the basis of the best history match, different secondary recovery techniques were simulated as a predictive study for enhancing the reservoir productivity.

  5. Potosi Reservoir Modeling; History and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Valerie; Leetaru, Hannes

    2014-09-30

    from using data from a single well in 2010 to the inclusion of data from three wells in 2013 which largely leverage the porosity and permeability logs plus knowledge of lost circulation zones. The first Potosi model (Potosi Geobody Model 2010) attempted to use the available seismic inversion data to inform the geomodel and predict vugular zones in advance of drilling VW1. Lost circulation zones in VW1 came in as the geologists predicted. The model was not implemented in subsequent simulation work. To date, reservoir models used for flow simulation work have relied predominately on Gaussian distributed properties (porosity and permeability) and have employed a single injection well. Potosi Model 2013b incorporated the new VW2 logs, and exhibited an extra level of sophistication by delineating the vugular intervals. This method added further realism that likely represents the best reservoir approximation to date. Where the 2010 reservoir models were 10 by 10 mi (16 by 16 km) in area, the 2013 models were expanded in size to 30 by 30 mi (48 by 48 km). The latest reservoir simulations show that a minimum of four injectors might be required to meet target injection rates. Still, there is data that requires further scrutiny and modeling methodologies that require testing for the Potosi Formation. This work is currently ongoing, and the next phase of the reservoir modeling intends to implement valuable data like porosity derived from seismic inversion, seismically derived geobodies, or a combination of both to further define vugular zones and the porosity distribution within the Potosi Formation. Understanding the dual porosity, dual permeability character of the Potosi remains the greatest challenge in representing this formation. Further analysis of the FMI* fullbore formation microimager data may aid in assessing this uncertainty. The Potosi Formation is indeed an interesting formation, and recommendations to further characterize it are included in the following list

  6. Reservoir Characterization, Production Characteristics, and Research Needs for Fluvial/Alluvial Reservoirs in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Cole, E.L.; Fowler, M.L.; Jackson, S.R.; Madden, M.P.; Raw-Schatzinger, V.; Salamy, S.P.; Sarathi, P.; Young, M.A.

    1999-04-28

    The Department of Energy's (DOE's) Oil Recovery Field Demonstration Program was initiated in 1992 to maximize the economically and environmentally sound recovery of oil from known domestic reservoirs and to preserve access to this resource. Cost-shared field demonstration projects are being initiated in geology defined reservoir classes which have been prioritized by their potential for incremental recovery and their risk of abandonment. This document defines the characteristics of the fifth geological reservoir class in the series, fluvial/alluvial reservoirs. The reservoirs of Class 5 include deposits of alluvial fans, braided streams, and meandering streams. Deposit morphologies vary as a complex function of climate and tectonics and are characterized by a high degree of heterogeneity to fluid flow as a result of extreme variations in water energy as the deposits formed.

  7. Characterization and modelling of a naturally fractured reservoir-caprock unit targeted for CO2 storage in arctic Norway

    NARCIS (Netherlands)

    Senger, K.; Mulrooney, M.; Schaaf, N.; Tveranger, J.; Braathen, A.; Ogata, K.; Olaussen, S.

    2017-01-01

    Successfully storing CO2 underground requires a good understanding of the subsurface at the storage site, and its robust representation in geological models. Geological models, and related simulations, provide important quantitative information on critical parameters for the optimal utilisation of

  8. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drillings. Annual technical progress report, June 13, 1996 to June 12, 1998

    Energy Technology Data Exchange (ETDEWEB)

    Nevans, Jerry W.; Blasingame, Tom; Doublet, Louis; Kelkar, Mohan; Freeman, George; Callard, Jeff; Moore, David; Davies, David; Vessell, Richard; Pregger, Brian; Dixon, Bill

    1999-04-27

    Infill drilling of wells on a uniform spacing, without regard to reservoir performance and characterization, does not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations. Other technologies, such as inter-well injection tracers and magnetic flow conditioners, can also aid in the efficient evaluation and operation of both injection and producing wells. The purpose of this project was to demonstrate useful and cost effective methods of exploitation of the shallow shelf carbonate reservoirs of the Permian Basin located in West Texas.

  9. Putting integrated reservoir characterization into practice - in house training

    Energy Technology Data Exchange (ETDEWEB)

    Wright, F.M. Jr.; Best, D.A.; Clarke, R.T. [Mobile Exploration and Producing Technical Center, Dallas, TX (United States)

    1997-08-01

    The need for even more efficient reservoir characterization and management has forced a change in the way Mobil Oil provides technical support to its production operations. We`ve learned that to be successful, a good understanding of the reservoir is essential. This includes an understanding of the technical and business significance of reservoir heterogeneities at different stages of field development. A multi-disciplinary understanding of the business of integrated reservoir characterization is essential and to facilitate this understanding, Mobil has developed a highly successful {open_quotes}Reservoir Characterization Field Seminar{close_quotes}. Through specific team based case studies that incorporate outcrop examples and data the program provides participants the opportunity to explore historic and alternative approaches to reservoir description, characterization and management. We explore appropriate levels and timing of data gathering, technology applications, risk assessment and management practices at different stages of field development. The case studies presented throughout the course are a unique element of the program which combine real life and hypothetical problem sets that explore how different technical disciplines interact, the approaches to a problem solving they use, the assumptions and uncertainties contained in their contributions and the impact those conclusions may have on other disciplines involved in the overall reservoir management process. The team building aspect of the course was an added bonus.

  10. Characterization of oil and gas reservoir heterogeneity

    Energy Technology Data Exchange (ETDEWEB)

    Tyler, N.; Barton, M.D.; Bebout, D.G.; Fisher, R.S.; Grigsby, J.D.; Guevara, E.; Holtz, M.; Kerans, C.; Nance, H.S.; Levey, R.A.

    1992-10-01

    Research described In this report addresses the internal architecture of two specific reservoir types: restricted-platform carbonates and fluvial-deltaic sandstones. Together, these two reservoir types contain more than two-thirds of the unrecovered mobile oil remaining ill Texas. The approach followed in this study was to develop a strong understanding of the styles of heterogeneity of these reservoir types based on a detailed outcrop description and a translation of these findings into optimized recovery strategies in select subsurface analogs. Research targeted Grayburg Formation restricted-platform carbonate outcrops along the Algerita Escarpment and In Stone Canyon In southeastern New Mexico and Ferron deltaic sandstones in central Utah as analogs for the North Foster (Grayburg) and Lake Creek (Wilcox) units, respectively. In both settings, sequence-stratigraphic style profoundly influenced between-well architectural fabric and permeability structure. It is concluded that reservoirs of different depositional origins can therefore be categorized Into a heterogeneity matrix'' based on varying intensity of vertical and lateral heterogeneity. The utility of the matrix is that it allows prediction of the nature and location of remaining mobile oil. Highly stratified reservoirs such as the Grayburg, for example, will contain a large proportion of vertically bypassed oil; thus, an appropriate recovery strategy will be waterflood optimization and profile modification. Laterally heterogeneous reservoirs such as deltaic distributary systems would benefit from targeted infill drilling (possibly with horizontal wells) and improved areal sweep efficiency. Potential for advanced recovery of remaining mobile oil through heterogeneity-based advanced secondary recovery strategies In Texas is projected to be an Incremental 16 Bbbl. In the Lower 48 States this target may be as much as 45 Bbbl at low to moderate oil prices over the near- to mid-term.

  11. Reservoir structural model updating using the Ensemble Kalman Filter

    Energy Technology Data Exchange (ETDEWEB)

    Seiler, Alexandra

    2010-09-15

    In reservoir characterization, a large emphasis is placed on risk management and uncertainty assessment, and the dangers of basing decisions on a single base-case reservoir model are widely recognized. In the last years, statistical methods for assisted history matching have gained popularity for providing integrated models with quantified uncertainty, conditioned on all available data. Structural modeling is the first step in a reservoir modeling work flow and consists in defining the geometrical framework of the reservoir, based on the information from seismic surveys and well data. Large uncertainties are typically associated with the processing and interpretation of seismic data. However, the structural model is often fixed to a single interpretation in history-matching work flows due to the complexity of updating the structural model and related reservoir grid. This thesis present a method that allows to account for the uncertainties in the structural model and continuously update the model and related uncertainties by assimilation of production data using the Ensemble Kalman Filter (EnKF). We consider uncertainties in the depth of the reservoir horizons and in the fault geometry, and assimilate production data, such as oil production rate, gas-oil ratio and water-cut. In the EnKF model-updating work flow, an ensemble of reservoir models, expressing explicitly the model uncertainty, is created. We present a parameterization that allows to generate different realizations of the structural model to account for the uncertainties in faults and horizons and that maintains the consistency throughout the reservoir characterization project, from the structural model to the prediction of production profiles. The uncertainty in the depth of the horizons is parameterized as simulated depth surfaces, the fault position as a displacement vector and the fault throw as a throw-scaling factor. In the EnKF, the model parameters and state variables are updated sequentially in

  12. Model based management of a reservoir system

    Energy Technology Data Exchange (ETDEWEB)

    Scharaw, B.; Westerhoff, T. [Fraunhofer IITB, Ilmenau (Germany). Anwendungszentrum Systemtechnik; Puta, H.; Wernstedt, J. [Technische Univ. Ilmenau (Germany)

    2000-07-01

    The main goals of reservoir management systems consist of prevention against flood water damages, the catchment of raw water and keeping all of the quality parameters within their limits besides controlling the water flows. In consideration of these goals a system model of the complete reservoir system Ohra-Schmalwasser-Tambach Dietharz was developed. This model has been used to develop optimized strategies for minimization of raw water production cost, for maximization of electrical energy production and to cover flood situations, as well. Therefore a proper forecast of the inflow to the reservoir from the catchment areas (especially flooding rivers) and the biological processes in the reservoir is important. The forecast model for the inflow to the reservoir is based on the catchment area model of Lorent and Gevers. It uses area precipitation, water supply from the snow cover, evapotranspiration and soil wetness data to calculate the amount of flow in rivers. The other aim of the project is to ensure the raw water quality using quality models, as well. Then a quality driven raw water supply will be possible. (orig.)

  13. Physical modelling of the Akkajaure reservoir

    Directory of Open Access Journals (Sweden)

    J. Sahlberg

    2003-01-01

    Full Text Available This paper describes the seasonal temperature development in the Akkajaure reservoir, one of the largest Swedish reservoirs. It lies in the headwaters of the river Lulealven in northern Sweden; it is 60 km long and 5 km wide with a maximum depth of 92 m. The maximum allowed variation in surface water level is 30 m. The temperature field in the reservoir is important for many biochemical processes. A one-dimensional lake model of the Akkajaure reservoir is developed from a lake model by Sahlberg (1983 and 1988. The dynamic eddy viscosity is calculated by a two equation turbulence model, a k–ε model and the hypolimnic eddy diffusivity formulation which is a function of the stability frequency (Hondzo et al., 1993. A comparison between calculated and measured temperature profiles showed a maximum discrepancy of 0.5–1.0°C over the period 1999-2002. Except for a few days in summer, the water temperature is vertically homogeneous. Over that period of years, a weak stratification of temperature occurred on only one to two weeks a year on different dates in July and August. This will have biological consequences. Keywords: temperature profile,reservoir, 1-D lake model, stratification, Sweden

  14. Application of integrated reservoir management and reservoir characterization to optimize infill drilling. Quarterly progress report, June 13, 1995--September 12, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Pande, P.K.

    1995-09-12

    At this stage of the reservoir characterization research, the main emphasis is on the geostatistics and reservoir simulation. Progress is reported on geological analysis, reservoir simulation, and reservoir management.

  15. Integration of dynamical data in a geostatistical model of reservoir; Integration des donnees dynamiques dans un modele geostatistique de reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Costa Reis, L.

    2001-01-01

    We have developed in this thesis a methodology of integrated characterization of heterogeneous reservoirs, from geologic modeling to history matching. This methodology is applied to the reservoir PBR, situated in Campos Basin, offshore Brazil, which has been producing since June 1979. This work is an extension of two other thesis concerning geologic and geostatistical modeling of the reservoir PBR from well data and seismic information. We extended the geostatistical litho-type model to the whole reservoir by using a particular approach of the non-stationary truncated Gaussian simulation method. This approach facilitated the application of the gradual deformation method to history matching. The main stages of the methodology for dynamic data integration in a geostatistical reservoir model are presented. We constructed a reservoir model and the initial difficulties in the history matching led us to modify some choices in the geological, geostatistical and flow models. These difficulties show the importance of dynamic data integration in reservoir modeling. The petrophysical property assignment within the litho-types was done by using well test data. We used an inversion procedure to evaluate the petrophysical parameters of the litho-types. The up-scaling is a necessary stage to reduce the flow simulation time. We compared several up-scaling methods and we show that the passage from the fine geostatistical model to the coarse flow model should be done very carefully. The choice of the fitting parameter depends on the objective of the study. In the case of the reservoir PBR, where water is injected in order to improve the oil recovery, the water rate of the producing wells is directly related to the reservoir heterogeneity. Thus, the water rate was chosen as the fitting parameter. We obtained significant improvements in the history matching of the reservoir PBR. First, by using a method we have proposed, called patchwork. This method allows us to built a coherent

  16. Seismic reservoir characterization: how can multicomponent data help?

    International Nuclear Information System (INIS)

    Li, Xiang-Yang; Zhang, Yong-Gang

    2011-01-01

    This paper discusses the concepts of multicomponent seismology and how it can be applied to characterize hydrocarbon reservoirs, illustrated using a 3D three-component real-data example from southwest China. Hydrocarbon reservoirs formed from subtle lithological changes, such as stratigraphic traps, may be delineated from changes in P- and S-wave velocities and impedances, whilst hydrocarbon reservoirs containing aligned fractures are anisotropic. Examination of the resultant split shear waves can give us a better definition of their internal structures. Furthermore, frequency-dependent variations in seismic attributes derived from multicomponent data can provide us with vital information about fluid type and distribution. Current practice and various examples have demonstrated the undoubted potential of multicomponent seismic in reservoir characterization. Despite all this, there are still substantial challenges ahead. In particular, the improvement and interpretation of converted-wave imaging are major hurdles that need to be overcome before multicomponent seismic becomes a mainstream technology

  17. Seismic reservoir characterization: how can multicomponent data help?

    Science.gov (United States)

    Li, Xiang-Yang; Zhang, Yong-Gang

    2011-06-01

    This paper discusses the concepts of multicomponent seismology and how it can be applied to characterize hydrocarbon reservoirs, illustrated using a 3D three-component real-data example from southwest China. Hydrocarbon reservoirs formed from subtle lithological changes, such as stratigraphic traps, may be delineated from changes in P- and S-wave velocities and impedances, whilst hydrocarbon reservoirs containing aligned fractures are anisotropic. Examination of the resultant split shear waves can give us a better definition of their internal structures. Furthermore, frequency-dependent variations in seismic attributes derived from multicomponent data can provide us with vital information about fluid type and distribution. Current practice and various examples have demonstrated the undoubted potential of multicomponent seismic in reservoir characterization. Despite all this, there are still substantial challenges ahead. In particular, the improvement and interpretation of converted-wave imaging are major hurdles that need to be overcome before multicomponent seismic becomes a mainstream technology.

  18. Reservoir characterization of the Mt. Simon Sandstone, Illinois Basin, USA

    Science.gov (United States)

    Frailey, S.M.; Damico, J.; Leetaru, H.E.

    2011-01-01

    The integration of open hole well log analyses, core analyses and pressure transient analyses was used for reservoir characterization of the Mt. Simon sandstone. Characterization of the injection interval provides the basis for a geologic model to support the baseline MVA model, specify pressure design requirements of surface equipment, develop completion strategies, estimate injection rates, and project the CO2 plume distribution.The Cambrian-age Mt. Simon Sandstone overlies the Precambrian granite basement of the Illinois Basin. The Mt. Simon is relatively thick formation exceeding 800 meters in some areas of the Illinois Basin. In the deeper part of the basin where sequestration is likely to occur at depths exceeding 1000 m, horizontal core permeability ranges from less than 1 ?? 10-12 cm 2 to greater than 1 ?? 10-8 cm2. Well log and core porosity can be up to 30% in the basal Mt. Simon reservoir. For modeling purposes, reservoir characterization includes absolute horizontal and vertical permeability, effective porosity, net and gross thickness, and depth. For horizontal permeability, log porosity was correlated with core. The core porosity-permeability correlation was improved by using grain size as an indication of pore throat size. After numerous attempts to identify an appropriate log signature, the calculated cementation exponent from Archie's porosity and resistivity relationships was used to identify which porosity-permeability correlation to apply and a permeability log was made. Due to the relatively large thickness of the Mt. Simon, vertical permeability is an important attribute to understand the distribution of CO2 when the injection interval is in the lower part of the unit. Only core analyses and specifically designed pressure transient tests can yield vertical permeability. Many reservoir flow models show that 500-800 m from the injection well most of the CO2 migrates upward depending on the magnitude of the vertical permeability and CO2 injection

  19. Improved characterization of reservoir behavior by integration of reservoir performances data and rock type distributions

    Energy Technology Data Exchange (ETDEWEB)

    Davies, D.K.; Vessell, R.K. [David K. Davies & Associates, Kingwood, TX (United States); Doublet, L.E. [Texas A& M Univ., College Station, TX (United States)] [and others

    1997-08-01

    An integrated geological/petrophysical and reservoir engineering study was performed for a large, mature waterflood project (>250 wells, {approximately}80% water cut) at the North Robertson (Clear Fork) Unit, Gaines County, Texas. The primary goal of the study was to develop an integrated reservoir description for {open_quotes}targeted{close_quotes} (economic) 10-acre (4-hectare) infill drilling and future recovery operations in a low permeability, carbonate (dolomite) reservoir. Integration of the results from geological/petrophysical studies and reservoir performance analyses provide a rapid and effective method for developing a comprehensive reservoir description. This reservoir description can be used for reservoir flow simulation, performance prediction, infill targeting, waterflood management, and for optimizing well developments (patterns, completions, and stimulations). The following analyses were performed as part of this study: (1) Geological/petrophysical analyses: (core and well log data) - {open_quotes}Rock typing{close_quotes} based on qualitative and quantitative visualization of pore-scale features. Reservoir layering based on {open_quotes}rock typing {close_quotes} and hydraulic flow units. Development of a {open_quotes}core-log{close_quotes} model to estimate permeability using porosity and other properties derived from well logs. The core-log model is based on {open_quotes}rock types.{close_quotes} (2) Engineering analyses: (production and injection history, well tests) Material balance decline type curve analyses to estimate total reservoir volume, formation flow characteristics (flow capacity, skin factor, and fracture half-length), and indications of well/boundary interference. Estimated ultimate recovery analyses to yield movable oil (or injectable water) volumes, as well as indications of well and boundary interference.

  20. Integration of rock typing methods for carbonate reservoir characterization

    International Nuclear Information System (INIS)

    Aliakbardoust, E; Rahimpour-Bonab, H

    2013-01-01

    Reservoir rock typing is the most important part of all reservoir modelling. For integrated reservoir rock typing, static and dynamic properties need to be combined, but sometimes these two are incompatible. The failure is due to the misunderstanding of the crucial parameters that control the dynamic behaviour of the reservoir rock and thus selecting inappropriate methods for defining static rock types. In this study, rock types were defined by combining the SCAL data with the rock properties, particularly rock fabric and pore types. First, air-displacing-water capillary pressure curues were classified because they are representative of fluid saturation and behaviour under capillary forces. Next the most important rock properties which control the fluid flow and saturation behaviour (rock fabric and pore types) were combined with defined classes. Corresponding petrophysical properties were also attributed to reservoir rock types and eventually, defined rock types were compared with relative permeability curves. This study focused on representing the importance of the pore system, specifically pore types in fluid saturation and entrapment in the reservoir rock. The most common tests in static rock typing, such as electrofacies analysis and porosity–permeability correlation, were carried out and the results indicate that these are not appropriate approaches for reservoir rock typing in carbonate reservoirs with a complicated pore system. (paper)

  1. Data Integration for the Generation of High Resolution Reservoir Models

    Energy Technology Data Exchange (ETDEWEB)

    Albert Reynolds; Dean Oliver; Gaoming Li; Yong Zhao; Chaohui Che; Kai Zhang; Yannong Dong; Chinedu Abgalaka; Mei Han

    2009-01-07

    The goal of this three-year project was to develop a theoretical basis and practical technology for the integration of geologic, production and time-lapse seismic data in a way that makes best use of the information for reservoir description and reservoir performance predictions. The methodology and practical tools for data integration that were developed in this research project have been incorporated into computational algorithms that are feasible for large scale reservoir simulation models. As the integration of production and seismic data require calibrating geological/geostatistical models to these data sets, the main computational tool is an automatic history matching algorithm. The following specific goals were accomplished during this research. (1) We developed algorithms for calibrating the location of the boundaries of geologic facies and the distribution of rock properties so that production and time-lapse seismic data are honored. (2) We developed and implemented specific procedures for conditioning reservoir models to time-lapse seismic data. (3) We developed and implemented algorithms for the characterization of measurement errors which are needed to determine the relative weights of data when conditioning reservoir models to production and time-lapse seismic data by automatic history matching. (4) We developed and implemented algorithms for the adjustment of relative permeability curves during the history matching process. (5) We developed algorithms for production optimization which accounts for geological uncertainty within the context of closed-loop reservoir management. (6) To ensure the research results will lead to practical public tools for independent oil companies, as part of the project we built a graphical user interface for the reservoir simulator and history matching software using Visual Basic.

  2. Carbonate reservoir characterization with lithofacies clustering and porosity prediction

    International Nuclear Information System (INIS)

    Al Moqbel, Abdulrahman; Wang, Yanghua

    2011-01-01

    One of the objectives in reservoir characterization is to quantitatively or semi-quantitatively map the spatial distribution of its heterogeneity and related properties. With the availability of 3D seismic data, artificial neural networks are capable of discovering the nonlinear relationship between seismic attributes and reservoir parameters. For a target carbonate reservoir, we adopt a two-stage approach to conduct characterization. First, we use an unsupervised neural network, the self-organizing map method, to classify the reservoir lithofacies. Then we apply a supervised neural network, the back-propagation algorithm, to quantitatively predict the porosity of the carbonate reservoir. Based on porosity maps at different time levels, we interpret the target reservoir vertically related to three depositional phases corresponding to, respectively, a lowstand system tract before sea water immersion, a highstand system tract when water covers organic deposits and a transition zone for the sea level falling. The highstand system is the most prospective zone, given the organic content deposited during this stage. The transition zone is also another prospective feature in the carbonate depositional system due to local build-ups

  3. Evaluation of Gaussian approximations for data assimilation in reservoir models

    KAUST Repository

    Iglesias, Marco A.

    2013-07-14

    The Bayesian framework is the standard approach for data assimilation in reservoir modeling. This framework involves characterizing the posterior distribution of geological parameters in terms of a given prior distribution and data from the reservoir dynamics, together with a forward model connecting the space of geological parameters to the data space. Since the posterior distribution quantifies the uncertainty in the geologic parameters of the reservoir, the characterization of the posterior is fundamental for the optimal management of reservoirs. Unfortunately, due to the large-scale highly nonlinear properties of standard reservoir models, characterizing the posterior is computationally prohibitive. Instead, more affordable ad hoc techniques, based on Gaussian approximations, are often used for characterizing the posterior distribution. Evaluating the performance of those Gaussian approximations is typically conducted by assessing their ability at reproducing the truth within the confidence interval provided by the ad hoc technique under consideration. This has the disadvantage of mixing up the approximation properties of the history matching algorithm employed with the information content of the particular observations used, making it hard to evaluate the effect of the ad hoc approximations alone. In this paper, we avoid this disadvantage by comparing the ad hoc techniques with a fully resolved state-of-the-art probing of the Bayesian posterior distribution. The ad hoc techniques whose performance we assess are based on (1) linearization around the maximum a posteriori estimate, (2) randomized maximum likelihood, and (3) ensemble Kalman filter-type methods. In order to fully resolve the posterior distribution, we implement a state-of-the art Markov chain Monte Carlo (MCMC) method that scales well with respect to the dimension of the parameter space, enabling us to study realistic forward models, in two space dimensions, at a high level of grid refinement. Our

  4. CALIBRATION OF SEISMIC ATTRIBUTES FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Wayne D. Pennington; Horacio Acevedo; Aaron Green; Joshua Haataja; Shawn Len; Anastasia Minaeva; Deyi Xie

    2002-10-01

    The project, ''Calibration of Seismic Attributes for Reservoir Calibration,'' is now complete. Our original proposed scope of work included detailed analysis of seismic and other data from two to three hydrocarbon fields; we have analyzed data from four fields at this level of detail, two additional fields with less detail, and one other 2D seismic line used for experimentation. We also included time-lapse seismic data with ocean-bottom cable recordings in addition to the originally proposed static field data. A large number of publications and presentations have resulted from this work, including several that are in final stages of preparation or printing; one of these is a chapter on ''Reservoir Geophysics'' for the new Petroleum Engineering Handbook from the Society of Petroleum Engineers. Major results from this project include a new approach to evaluating seismic attributes in time-lapse monitoring studies, evaluation of pitfalls in the use of point-based measurements and facies classifications, novel applications of inversion results, improved methods of tying seismic data to the wellbore, and a comparison of methods used to detect pressure compartments. Some of the data sets used are in the public domain, allowing other investigators to test our techniques or to improve upon them using the same data. From the public-domain Stratton data set we have demonstrated that an apparent correlation between attributes derived along ''phantom'' horizons are artifacts of isopach changes; only if the interpreter understands that the interpretation is based on this correlation with bed thickening or thinning, can reliable interpretations of channel horizons and facies be made. From the public-domain Boonsville data set we developed techniques to use conventional seismic attributes, including seismic facies generated under various neural network procedures, to subdivide regional facies determined from logs into

  5. Geological model of supercritical geothermal reservoir related to subduction system

    Science.gov (United States)

    Tsuchiya, Noriyoshi

    2017-04-01

    Following the Great East Japan Earthquake and the accident at the Fukushima Daiichi Nuclear power station on 3.11 (11th March) 2011, geothermal energy came to be considered one of the most promising sources of renewable energy for the future in Japan. The temperatures of geothermal fields operating in Japan range from 200 to 300 °C (average 250 °C), and the depths range from 1000 to 2000 m (average 1500 m). In conventional geothermal reservoirs, the mechanical behavior of the rocks is presumed to be brittle, and convection of the hydrothermal fluid through existing network is the main method of circulation in the reservoir. In order to minimize induced seismicity, a rock mass that is "beyond brittle" is one possible candidate, because the rock mechanics of "beyond brittle" material is one of plastic deformation rather than brittle failure. Supercritical geothermal resources could be evaluated in terms of present volcanic activities, thermal structure, dimension of hydrothermal circulation, properties of fracture system, depth of heat source, depth of brittle factures zone, dimension of geothermal reservoir. On the basis of the GIS, potential of supercritical geothermal resources could be characterized into the following four categories. 1. Promising: surface manifestation d shallow high temperature, 2 Probability: high geothermal gradient, 3 Possibility: Aseismic zone which indicates an existence of melt, 4 Potential : low velocity zone which indicates magma input. Base on geophysical data for geothermal reservoirs, we have propose adequate tectonic model of development of the supercritical geothermal reservoirs. To understand the geological model of a supercritical geothermal reservoir, granite-porphyry system, which had been formed in subduction zone, was investigated as a natural analog of the supercritical geothermal energy system. Quartz veins, hydrothermal breccia veins, and glassy veins are observed in a granitic body. The glassy veins formed at 500-550

  6. Ensemble-Based Data Assimilation in Reservoir Characterization: A Review

    Directory of Open Access Journals (Sweden)

    Seungpil Jung

    2018-02-01

    Full Text Available This paper presents a review of ensemble-based data assimilation for strongly nonlinear problems on the characterization of heterogeneous reservoirs with different production histories. It concentrates on ensemble Kalman filter (EnKF and ensemble smoother (ES as representative frameworks, discusses their pros and cons, and investigates recent progress to overcome their drawbacks. The typical weaknesses of ensemble-based methods are non-Gaussian parameters, improper prior ensembles and finite population size. Three categorized approaches, to mitigate these limitations, are reviewed with recent accomplishments; improvement of Kalman gains, add-on of transformation functions, and independent evaluation of observed data. The data assimilation in heterogeneous reservoirs, applying the improved ensemble methods, is discussed on predicting unknown dynamic data in reservoir characterization.

  7. 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

  8. Quantum Bayesian perspective for intelligence reservoir characterization, monitoring and management

    Science.gov (United States)

    Lozada Aguilar, Miguel Ángel; Khrennikov, Andrei; Oleschko, Klaudia; de Jesús Correa, María

    2017-10-01

    The paper starts with a brief review of the literature about uncertainty in geological, geophysical and petrophysical data. In particular, we present the viewpoints of experts in geophysics on the application of Bayesian inference and subjective probability. Then we present arguments that the use of classical probability theory (CP) does not match completely the structure of geophysical data. We emphasize that such data are characterized by contextuality and non-Kolmogorovness (the impossibility to use the CP model), incompleteness as well as incompatibility of some geophysical measurements. These characteristics of geophysical data are similar to the characteristics of quantum physical data. Notwithstanding all this, contextuality can be seen as a major deviation of quantum theory from classical physics. In particular, the contextual probability viewpoint is the essence of the Växjö interpretation of quantum mechanics. We propose to use quantum probability (QP) for decision-making during the characterization, modelling, exploring and management of the intelligent hydrocarbon reservoir. Quantum Bayesianism (QBism), one of the recently developed information interpretations of quantum theory, can be used as the interpretational basis for such QP decision-making in geology, geophysics and petroleum projects design and management. This article is part of the themed issue `Second quantum revolution: foundational questions'.

  9. Quantum Bayesian perspective for intelligence reservoir characterization, monitoring and management.

    Science.gov (United States)

    Lozada Aguilar, Miguel Ángel; Khrennikov, Andrei; Oleschko, Klaudia; de Jesús Correa, María

    2017-11-13

    The paper starts with a brief review of the literature about uncertainty in geological, geophysical and petrophysical data. In particular, we present the viewpoints of experts in geophysics on the application of Bayesian inference and subjective probability. Then we present arguments that the use of classical probability theory (CP) does not match completely the structure of geophysical data. We emphasize that such data are characterized by contextuality and non-Kolmogorovness (the impossibility to use the CP model), incompleteness as well as incompatibility of some geophysical measurements. These characteristics of geophysical data are similar to the characteristics of quantum physical data. Notwithstanding all this, contextuality can be seen as a major deviation of quantum theory from classical physics. In particular, the contextual probability viewpoint is the essence of the Växjö interpretation of quantum mechanics. We propose to use quantum probability (QP) for decision-making during the characterization, modelling, exploring and management of the intelligent hydrocarbon reservoir Quantum Bayesianism (QBism), one of the recently developed information interpretations of quantum theory, can be used as the interpretational basis for such QP decision-making in geology, geophysics and petroleum projects design and management.This article is part of the themed issue 'Second quantum revolution: foundational questions'. © 2017 The Author(s).

  10. Reservoir Characterization and CO2 Plume Migration Modeling Based on Bottom-hole Pressure Data: An Example from the AEP Mountaineer Geological Storage Project

    Science.gov (United States)

    Mishra, Srikanta; Kelley, Mark; Oruganti, YagnaDeepika; Bhattacharya, Indra; Spitznogle, Gary

    2014-05-01

    We present an integrated approach for formation permeability estimation, front tracking, reservoir model calibration, and plume migration modeling based on injection rate and down-hole pressure data from CO2 geologic sequestration projects. The data are taken from the 20 MW CO2 capture and storage project at American Electric Power's Mountaineer Plant in West Virginia, USA. The Mountaineer CO2 injection system consists of two injection wells - one in the Copper Ridge Dolomite formation and one in the Rose Run sandstone formation, and three deep observation wells that were operational between October 2009 and May 2011. Approximately 27000 MT and 10000 MT were injected into the Copper Ridge dolomite formation and Rose Run sandstone formation, respectively. A wealth of pressure and rate data from injection and observation wells is available covering a series of injection and pressure falloff events. The methodology developed and applied for interpreting and integrating the data during reservoir analysis and modeling from the Rose Run formation is the subject of this paper. For the analysis of transient pressure data at the injection and observation wells, the CO2 storage reservoir is conceptualized as a radial composite system, where the inner (invaded) zone consists of both supercritical CO2 and brine, and the outer (uninvaded) zone consists of undisturbed brine. Using established analytical solutions for analyzing fluid injection problems in the petroleum reservoir engineering literature, we show how the late-time pressure derivative response from both injection and observation wells will be identical - reflecting the permeability-thickness product of the undisturbed brine-filled formation. We also show how the expanding CO2 plume affects the "effective" compressibility that can be estimated by history matching injection-falloff data and how this can be used to develop a relationship between the plume radius and "effective" compressibility. This provides a novel non

  11. RESERVOIR CHARACTERIZATION USING SEISMIC AND WELL ...

    African Journals Online (AJOL)

    Osondu

    2012-06-19

    Jun 19, 2012 ... analysis of the entire pay zone is impractical. A typical seismic section of Niger Delta will reveal number of synsedimentary structures resulting from the deltaic tectonic. The structures include growth faults; which are normal faults characterization by a concave fault plane resulting from the decrease of dip at ...

  12. Characterization of fractured reservoirs joint inversion of seismic and production data

    Energy Technology Data Exchange (ETDEWEB)

    Shahraini, Ali

    2011-03-15

    Significant amounts of oil and gas reserves are trapped in fractured reservoirs. A proper characterization of fractured reservoirs can contribute to better reservoir management, including optimum well placement, planning of enhanced oil recovery (EOR) methods, well completion and so on. Characterization of fractured (and faulted) reservoirs has been a challenging and complicated task due to the high degree of heterogeneity and anisotropy that exists in this kind of reservoirs. In this thesis I look at the problem of fractured reservoir characterization as an inverse problem, and try to estimate the uncertain fracture parameters by joint inversion (or history matching) of seismic and production data. Updating a reservoir model to behave as closely as possible to the real reservoir is called history matching, which generally has a non-unique solution. History matching is a time consuming problem. Using both production and seismic data can help to narrow the solution space. This work aims to propose and develop work flows and methodologies for improved characterization of fractured reservoirs. It is based on an integrated approach using both seismic and production data in the characterization process. The fluid flow- seismic wave system for fractured reservoir characterization consists of a reservoir simulator coupled to consistent rock physics models and forward seismic modeling tools. A consistent (computationally inexpensive) rock physics model is used to calculate the effective permeability and stiffness tensors of fractured porous media from a limited number of uncertain fracture parameters. Based on the calculated effective permeability tensors, the reservoir simulator calculates production data such as well oil production, well bottom hole pressure, well water cut, saturation and pressure for all grid blocks at specific time steps. Similarly, using the effective stiffness tensors (calculated from saturation maps and assumed fracture parameters), seismic

  13. Reservoir pressure evolution model during exploration drilling

    Directory of Open Access Journals (Sweden)

    Korotaev B. A.

    2017-03-01

    Full Text Available Based on the analysis of laboratory studies and literature data the method for estimating reservoir pressure in exploratory drilling has been proposed, it allows identify zones of abnormal reservoir pressure in the presence of seismic data on reservoir location depths. This method of assessment is based on developed at the end of the XX century methods using d- and σ-exponentials taking into account the mechanical drilling speed, rotor speed, bit load and its diameter, lithological constant and degree of rocks' compaction, mud density and "regional density". It is known that in exploratory drilling pulsation of pressure at the wellhead is observed. Such pulsation is a consequence of transferring reservoir pressure through clay. In the paper the mechanism for transferring pressure to the bottomhole as well as the behaviour of the clay layer during transmission of excess pressure has been described. A laboratory installation has been built, it has been used for modelling pressure propagation to the bottomhole of the well through a layer of clay. The bulge of the clay layer is established for 215.9 mm bottomhole diameter. Functional correlation of pressure propagation through the layer of clay has been determined and a reaction of the top clay layer has been shown to have bulge with a height of 25 mm. A pressure distribution scheme (balance has been developed, which takes into account the distance from layers with abnormal pressure to the bottomhole. A balance equation for reservoir pressure evaluation has been derived including well depth, distance from bottomhole to the top of the formation with abnormal pressure and density of clay.

  14. Crosswell electromagnetic imaging for geothermal reservoir characterization - a feasibility study

    Science.gov (United States)

    Samrock, Friedemann; Saar, Martin O.

    2016-04-01

    Most regions in the world do not have ready access to natural convective hydrothermal resources. To use deep geothermal heat as a viable energy resource in low-permeability formations, permeable fracture networks have to be created artificially to enable deep fluid circulation for advective heat transport to a production well. Such generation of enhanced geothermal systems (EGS) is studied in the "Deep Underground Geothermal (DUG)" laboratory at the Grimsel pass, Switzerland. Here, an underground experiment is conducted by hydraulically stimulating a pre-existing shear zone within crystalline rock. The objectives of this project are to better describe and understand the processes acting during reservoir generation. We perform a feasibility study to evaluate the capability of low-frequency crosswell electromagnetic (EM) tomography for mapping of stimulation-induced changes in electrical conductivity. First numerical results show that crosswell EM data are generally sensitive to the inter-well conductivity distribution, which is affected by properties such as interconnected porosity, permeability and the presence of fluids. It thereby provides important information for characterization of potential EGS reservoirs. We present a 3-D forward modeling and inversion study using synthetic data and under realistic conditions, these include the true borehole spacing and the observed electromagnetic noise level in the DUG laboratory. Based on these results we discuss the system requirements and the capability of crosswell EM to recover the inter-well structure and stimulation-induced changes. Besides the numerical study we report on the current status of instrumentation and realization of crosswell EM measurements at the DUG laboratory.

  15. Characterization of oil and gas reservoir heterogeneity. Annual report, November 1, 1990--October 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    The objective of the cooperative research program is to characterize Alaskan reservoirs in terms of their reserves, physical and chemical properties, geologic configuration and structure, and the development potential. The tasks completed during this period include: (1) geologic reservoir description of Endicott Field; (2) petrographic characterization of core samples taken from selected stratigraphic horizons of the West Sak and Ugnu (Brookian) wells; (3) development of a polydispersed thermodynamic model for predicting asphaltene equilibria and asphaltene precipitation from crude oil-solvent mixtures, and (4) preliminary geologic description of the Milne Point Unit.

  16. Development and application of 3-D fractal reservoir model based on collage theorem

    Energy Technology Data Exchange (ETDEWEB)

    Kim, I.K.; Kim, K.S.; Sung, W.M. [Hanyang Univ., Seoul (Korea, Republic of)

    1995-04-30

    Reservoir characterization is the essential process to accurately evaluate the reservoir and has been conducted by geostatistical method, SRA algorithm, and etc. The characterized distribution of heterogeneous property by these methods shows randomly distributed phenomena, and does not present anomalous shape of property variation at discontinued space as compared with the observed shape in nature. This study proposed a new algorithm of fractal concept based on collage theorem, which can virtually present not only geometric shape of irregular and anomalous pore structures or coastlines, but also property variation for discontinuously observed data. With a basis of fractal concept, three dimensional fractal reservoir model was developed to more accurately characterize the heterogeneous reservoir. We performed analysis of pre-predictable hypothetically observed permeability data by using the fractal reservoir model. From the results, we can recognize that permeability distributions in the areal view or the cross-sectional view were consistent with the observed data. (author). 8 refs., 1 tab., 6 figs.

  17. Reservoir characterization and enhanced oil recovery research. Annual report, September 1988--August 1989

    Energy Technology Data Exchange (ETDEWEB)

    Lake, L.W.; Pope, G.A.; Schechter, R.S.

    1992-03-01

    The research in this annual report falls into three tasks each dealing with a different aspect of enhanced oil recovery. The first task strives to develop procedures for accurately modeling reservoirs for use as input to numerical simulation flow models. This action describes how we have used a detail characterization of an outcrop to provide insights into what features are important to fluid flow modeling. The second task deals with scaling-up and modeling chemical and solvent EOR processes. In a sense this task is the natural extension of task 1 and, in fact, one of the subtasks uses many of the same statistical procedures for insight into the effects of viscous fingering and heterogeneity. The final task involves surfactants and their interactions with carbon dioxide and reservoir minerals. This research deals primarily with phenomena observed when aqueous surfactant solutions are injected into oil reservoirs.

  18. Application of reservoir characterization and advanced technology to improve recovery and economic in a lower quality shallow shelf carbonate reservoir. First quarter 1995

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, A.M.

    1995-05-04

    The focus of the project is to show that the use of advanced technology can improve the economics of CO{sub 2} projects in low permeability reservoirs. The approach involves the use of tomography, 3-D seismic and detailed petrophysical descriptions to enhance reservoir characterization. Cyclic CO{sub 2} stimulations and model designed frac treatments will be used to increase and facilitate oil recovery to improve project economics. The detailed reservoir characterization will be used to create a geological model for use in simulation to arrive at an optimum operating plan to be instituted during the second budget period. Objectives to be accomplished during the third quarter include: (1) Complete petrophysical description on cores from observation wells. (2) Apply petrophysical data to geologic model. (3) Conduct additional laboratory analysis on cores and fluids. (4) Refine 3-D seismic interpretations. (5) Complete tomography surveys. (6) Process tomography data. (7) Establish relationship between seismic and tomography interpretations. (8) Conduct preliminary simulator runs with improved geologic model. (9) Evaluate results of cyclic CO{sub 2} stimulation treatments. (10) Design frac treatment for linear flood fronts. All of the above objectives were worked on during the current quarter and the overall project is fairly well on schedule. The area of greatest concern time-wise is reservoir simulation. The simulator depends on the geologic model, which in turn depends on the petrophysical, 3-D seismic and tomography interpretations. Hence, the final geologic model won`t be available until all of the reservoir characterization work is completed.

  19. The Potosi Reservoir Model 2013c, Property Modeling Update

    Energy Technology Data Exchange (ETDEWEB)

    Adushita, Yasmin; Smith, Valerie; Leetaru, Hannes

    2014-09-30

    test and pressure interference test among the wells could be considered to evaluate the local vugs permeability, extent, and interconnectivity. Facies modeling within the Potosi has yet to be thoroughly addressed. The carbonates during the time of deposition are believed to be regionally extensive. However, it may be worth delineating the reservoir with other regional wells or modern day analogues to understand the extent of the Potosi. More specifically, the model could incorporate lateral changes or trends if deemed necessary to represent facies transition. Data acquisitions to characterize the fracture pressure gradient, the formation water properties, the relative permeability, and the capillary pressure could also be considered in order to allow a more rigorous evaluation of the Potosi storage performance. A simulation using several injectors could also be considered to determine the required number of wells and appropriate spacing to achieve the injection target while taking into account the pressure interference.

  20. Reservoir characterization by multiattribute analysis: The Orito field case

    Directory of Open Access Journals (Sweden)

    Montes Luis

    2010-12-01

    Full Text Available

    In order to characterize the Caballos formation reservoir in the Orito field in the Putumayo basin - Colombia, a multiattribute analysis was applied to a 50 km2 seismic volume along with 16 boreholes. Some properties of the reservoir were reliably estimated and very accurate when compared with well data. The porosity, permeability and volume of shale were calculated in the seismic volume by at least second order multivariate polynomial. A good correlation between porosity and acoustic impedance was observed by means of crossplot analysis performed on properties measured and estimated in cores or borehole logs as well as on properties calculated in the seismic volume. The estimated property values were well behaved according to the rocks physics analysis. With the property maps generated and the geological environments of the reservoir a new interpretation of the Caballos formation was established. High correlation coefficients and low estimated errors point out competence to calculate these three reservoir properties in places far from the influence of the wells. The multiple equation system was established through weighted hierarchical grouping of attributes and their coefficients calculated applying the inverse generalized matrix method.

  1. Seismic attributes characterization for Albian reservoirs in shallow Santos Basin

    Energy Technology Data Exchange (ETDEWEB)

    Vincentelli, Maria Gabriela C.; Barbosa, Mauro [HRT Petroleum, Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The Santos basin southwest area is characterized by gas production, but it shows an exploratory problem due to the lack of good reservoirs facies. The main reservoirs are the Albian calcarenites, which show low porosities values (about 2%) in the northwest portion of the study area. From wire log analysis, it was interpreted that the porosity values can reach 15% at the south-west portion, both in the Caravela, Cavalo Marinho and Tubarao oil/gas fields and in the neighborhood of these fields. In order to find the best places to drill exploration wells at Shallow Santos, it is recommended to apply analyses of seismic attributes including: main average amplitude, energy, RMS, main amplitude, etc. Once the application of this methodology is restricted to 3D seismic data, in this study, a pseudo-3D seismic volume was built from 9,635 km of seismic lines, and 13 wells were used for reservoir facies control. As a result, the presence of good facies reservoirs in this area of the basin is restricted to trends with a NE-SW direction, and their presence is not only associated with the structural highs, this fact explains the dry wells over rollover structures. (author)

  2. Fracture Characterization in Enhanced Geothermal Systems by Wellbore and Reservoir Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Horne, Roland N.; Li, Kewen; Alaskar, Mohammed; Ames, Morgan; Co, Carla; Juliusson, Egill; Magnusdottir, Lilja

    2012-06-30

    This report highlights the work that was done to characterize fractured geothermal reservoirs using production data. That includes methods that were developed to infer characteristic functions from production data and models that were designed to optimize reinjection scheduling into geothermal reservoirs, based on these characteristic functions. The characterization method provides a robust way of interpreting tracer and flow rate data from fractured reservoirs. The flow-rate data are used to infer the interwell connectivity, which describes how injected fluids are divided between producers in the reservoir. The tracer data are used to find the tracer kernel for each injector-producer connection. The tracer kernel describes the volume and dispersive properties of the interwell flow path. A combination of parametric and nonparametric regression methods were developed to estimate the tracer kernels for situations where data is collected at variable flow-rate or variable injected concentration conditions. The characteristic functions can be used to calibrate thermal transport models, which can in turn be used to predict the productivity of geothermal systems. This predictive model can be used to optimize injection scheduling in a geothermal reservoir, as is illustrated in this report.

  3. Facies-constrained FWI: Toward application to reservoir characterization

    KAUST Repository

    Kamath, Nishant

    2017-11-01

    The most common approach to obtaining reservoir properties from seismic data exploits the amplitude variation with offset response of reflected waves. However, structural complexity and errors in the velocity model can severely reduce the quality of the inverted results. Full-waveform inversion (FWI) has shown a lot of promise in obtaining high-resolution velocity models for depth imaging. We propose supplementing FWI with rock-physics constraints obtained from borehole data to invert for reservoir properties. The constraints are imposed by adding appropriately weighted regularization terms to the objective function. The advantages of this technique over conventional FWI algorithms are shown by conducting synthetic tests for both isotropic and VTI (transversely isotropic with a vertical symmetry axis) models. The medium parameterization for FWI is selected using radiation (scattering) patterns of perturbations in the model parameters.

  4. Real-time reservoir geological model updating using the hybrid EnKF and geostatistical technique

    Energy Technology Data Exchange (ETDEWEB)

    Li, H.; Chen, S.; Yang, D. [Regina Univ., SK (Canada). Petroleum Technology Research Centre

    2008-07-01

    Reservoir simulation plays an important role in modern reservoir management. Multiple geological models are needed in order to analyze the uncertainty of a given reservoir development scenario. Ideally, dynamic data should be incorporated into a reservoir geological model. This can be done by using history matching and tuning the model to match the past performance of reservoir history. This study proposed an assisted history matching technique to accelerate and improve the matching process. The Ensemble Kalman Filter (EnKF) technique, which is an efficient assisted history matching method, was integrated with a conditional geostatistical simulation technique to dynamically update reservoir geological models. The updated models were constrained to dynamic data, such as reservoir pressure and fluid saturations, and approaches geologically realistic at each time step by using the EnKF technique. The new technique was successfully applied in a heterogeneous synthetic reservoir. The uncertainty of the reservoir characterization was significantly reduced. More accurate forecasts were obtained from the updated models. 3 refs., 2 figs.

  5. Application of integrated reservoir management and reservoir characterization to optimize infill drilling. Annual report, June 13, 1994--June 12, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Pande, P.K.

    1996-11-01

    This project has used a multi-disciplinary approach employing geology, geophysics, and engineering to conduct advanced reservoir characterization and management activities to design and implement an optimized infill drilling program at the North Robertson (Clearfork) Unit in Gaines County, Texas. The activities during the first Budget Period have consisted of developing an integrated reservoir description from geological, engineering, and geostatistical studies, and using this description for reservoir flow simulation. Specific reservoir management activities are being identified and tested. The geologically targeted infill drilling program will be implemented using the results of this work. A significant contribution of this project is to demonstrate the use of cost-effective reservoir characterization and management tools that will be helpful to both independent and major operators for the optimal development of heterogeneous, low permeability shallow-shelf carbonate (SSC) reservoirs. The techniques that are outlined for the formulation of an integrated reservoir description apply to all oil and gas reservoirs, but are specifically tailored for use in the heterogeneous, low permeability carbonate reservoirs of West Texas.

  6. Modeling a distributed environment for a petroleum reservoir engineering application with software product line

    International Nuclear Information System (INIS)

    Scheidt, Rafael de Faria; Vilain, Patrícia; Dantas, M A R

    2014-01-01

    Petroleum reservoir engineering is a complex and interesting field that requires large amount of computational facilities to achieve successful results. Usually, software environments for this field are developed without taking care out of possible interactions and extensibilities required by reservoir engineers. In this paper, we present a research work which it is characterized by the design and implementation based on a software product line model for a real distributed reservoir engineering environment. Experimental results indicate successfully the utilization of this approach for the design of distributed software architecture. In addition, all components from the proposal provided greater visibility of the organization and processes for the reservoir engineers

  7. APPLICATION OF RESERVOIR CHARACTERIZATION AND ADVANCED TECHNOLOGY TO IMPROVE RECOVERY AND ECONOMICS IN A LOWER QUALITY SHALLOW SHELF SANANDRES RESERVOIR

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2003-01-15

    The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs. Therefore, the majority of Budget Period 1 was devoted to reservoir characterization. Technologies being demonstrated include: (1) Advanced petrophysics; (2) Three-dimensional (3-D) seismic; (3) Crosswell bore tomography; (4) Advanced reservoir simulation; (5) Carbon dioxide (CO{sub 2}) stimulation treatments; (6) Hydraulic fracturing design and monitoring; (7) Mobility control agents.

  8. Statistical modeling of geopressured geothermal reservoirs

    Science.gov (United States)

    Ansari, Esmail; Hughes, Richard; White, Christopher D.

    2017-06-01

    Identifying attractive candidate reservoirs for producing geothermal energy requires predictive models. In this work, inspectional analysis and statistical modeling are used to create simple predictive models for a line drive design. Inspectional analysis on the partial differential equations governing this design yields a minimum number of fifteen dimensionless groups required to describe the physics of the system. These dimensionless groups are explained and confirmed using models with similar dimensionless groups but different dimensional parameters. This study models dimensionless production temperature and thermal recovery factor as the responses of a numerical model. These responses are obtained by a Box-Behnken experimental design. An uncertainty plot is used to segment the dimensionless time and develop a model for each segment. The important dimensionless numbers for each segment of the dimensionless time are identified using the Boosting method. These selected numbers are used in the regression models. The developed models are reduced to have a minimum number of predictors and interactions. The reduced final models are then presented and assessed using testing runs. Finally, applications of these models are offered. The presented workflow is generic and can be used to translate the output of a numerical simulator into simple predictive models in other research areas involving numerical simulation.

  9. Integrated reservoir characterization of a Posidonia Shale outcrop analogue: From serendipity to understanding

    NARCIS (Netherlands)

    Zijp, M.H.A.A.; Veen, J.H. ten; Verreussel, R.M.C.H.; Ventra, D.

    2014-01-01

    Shale gas reservoir stimulation procedures (e.g. hydraulic fracturing) require upfront prediction and planning that should be supported by a comprehensive reservoir characterization. Therefore, understanding shale depositional processes and associated vertical and lateral sedimentological

  10. Modeling of reservoir operation in UNH global hydrological model

    Science.gov (United States)

    Shiklomanov, Alexander; Prusevich, Alexander; Frolking, Steve; Glidden, Stanley; Lammers, Richard; Wisser, Dominik

    2015-04-01

    Climate is changing and river flow is an integrated characteristic reflecting numerous environmental processes and their changes aggregated over large areas. Anthropogenic impacts on the river flow, however, can significantly exceed the changes associated with climate variability. Besides of irrigation, reservoirs and dams are one of major anthropogenic factor affecting streamflow. They distort hydrological regime of many rivers by trapping of freshwater runoff, modifying timing of river discharge and increasing the evaporation rate. Thus, reservoirs is an integral part of the global hydrological system and their impacts on rivers have to be taken into account for better quantification and understanding of hydrological changes. We developed a new technique, which was incorporated into WBM-TrANS model (Water Balance Model-Transport from Anthropogenic and Natural Systems) to simulate river routing through large reservoirs and natural lakes based on information available from freely accessible databases such as GRanD (the Global Reservoir and Dam database) or NID (National Inventory of Dams for US). Different formulations were applied for unregulated spillway dams and lakes, and for 4 types of regulated reservoirs, which were subdivided based on main purpose including generic (multipurpose), hydropower generation, irrigation and water supply, and flood control. We also incorporated rules for reservoir fill up and draining at the times of construction and decommission based on available data. The model were tested for many reservoirs of different size and types located in various climatic conditions using several gridded meteorological data sets as model input and observed daily and monthly discharge data from GRDC (Global Runoff Data Center), USGS Water Data (US Geological Survey), and UNH archives. The best results with Nash-Sutcliffe model efficiency coefficient in the range of 0.5-0.9 were obtained for temperate zone of Northern Hemisphere where most of large

  11. Technology for Increasing Geothermal Energy Productivity. Computer Models to Characterize the Chemical Interactions of Goethermal Fluids and Injectates with Reservoir Rocks, Wells, Surface Equiptment

    Energy Technology Data Exchange (ETDEWEB)

    Nancy Moller Weare

    2006-07-25

    This final report describes the results of a research program we carried out over a five-year (3/1999-9/2004) period with funding from a Department of Energy geothermal FDP grant (DE-FG07-99ID13745) and from other agencies. The goal of research projects in this program were to develop modeling technologies that can increase the understanding of geothermal reservoir chemistry and chemistry-related energy production processes. The ability of computer models to handle many chemical variables and complex interactions makes them an essential tool for building a fundamental understanding of a wide variety of complex geothermal resource and production chemistry. With careful choice of methodology and parameterization, research objectives were to show that chemical models can correctly simulate behavior for the ranges of fluid compositions, formation minerals, temperature and pressure associated with present and near future geothermal systems as well as for the very high PT chemistry of deep resources that is intractable with traditional experimental methods. Our research results successfully met these objectives. We demonstrated that advances in physical chemistry theory can be used to accurately describe the thermodynamics of solid-liquid-gas systems via their free energies for wide ranges of composition (X), temperature and pressure. Eight articles on this work were published in peer-reviewed journals and in conference proceedings. Four are in preparation. Our work has been presented at many workshops and conferences. We also considerably improved our interactive web site (geotherm.ucsd.edu), which was in preliminary form prior to the grant. This site, which includes several model codes treating different XPT conditions, is an effective means to transfer our technologies and is used by the geothermal community and other researchers worldwide. Our models have wide application to many energy related and other important problems (e.g., scaling prediction in petroleum

  12. Technology for Increasing Geothermal Energy Productivity. Computer Models to Characterize the Chemical Interactions of Geothermal Fluids and Injectates with Reservoir Rocks, Wells, Surface Equipment

    International Nuclear Information System (INIS)

    Nancy Moller Weare

    2006-01-01

    This final report describes the results of a research program we carried out over a five-year (3/1999-9/2004) period with funding from a Department of Energy geothermal FDP grant (DE-FG07-99ID13745) and from other agencies. The goal of research projects in this program were to develop modeling technologies that can increase the understanding of geothermal reservoir chemistry and chemistry-related energy production processes. The ability of computer models to handle many chemical variables and complex interactions makes them an essential tool for building a fundamental understanding of a wide variety of complex geothermal resource and production chemistry. With careful choice of methodology and parameterization, research objectives were to show that chemical models can correctly simulate behavior for the ranges of fluid compositions, formation minerals, temperature and pressure associated with present and near future geothermal systems as well as for the very high PT chemistry of deep resources that is intractable with traditional experimental methods. Our research results successfully met these objectives. We demonstrated that advances in physical chemistry theory can be used to accurately describe the thermodynamics of solid-liquid-gas systems via their free energies for wide ranges of composition (X), temperature and pressure. Eight articles on this work were published in peer-reviewed journals and in conference proceedings. Four are in preparation. Our work has been presented at many workshops and conferences. We also considerably improved our interactive web site (geotherm.ucsd.edu), which was in preliminary form prior to the grant. This site, which includes several model codes treating different XPT conditions, is an effective means to transfer our technologies and is used by the geothermal community and other researchers worldwide. Our models have wide application to many energy related and other important problems (e.g., scaling prediction in petroleum

  13. Discrete Fracture Network Characterization of Fractured Shale Reservoirs with Implications to Hydraulic Fracturing Optimization

    Science.gov (United States)

    Jin, G.

    2016-12-01

    Shales are important petroleum source rocks and reservoir seals. Recent developments in hydraulic fracturing technology have facilitated high gas production rates from shale and have had a strong impact on the U.S. gas supply and markets. Modeling of effective permeability for fractured shale reservoirs has been challenging because the presence of a fracture network significantly alters the reservoir hydrologic properties. Due to the frequent occurrence of fracture networks, it is of vital importance to characterize fracture networks and to investigate how these networks can be used to optimize the hydraulic fracturing. We have conducted basic research on 3-D fracture permeability characterization and compartmentization analyses for fractured shale formations, which takes the advantages of the discrete fracture networks (DFN). The DFN modeling is a stochastic modeling approach using the probabilistic density functions of fractures. Three common scenarios of DFN models have been studied for fracture permeability mapping using our previously proposed techniques. In DFN models with moderately to highly concentrated fractures, there exists a representative element volume (REV) for fracture permeability characterization, which indicates that the fractured reservoirs can be treated as anisotropic homogeneous media. Hydraulic fracturing will be most effective if the orientation of the hydraulic fracture is perpendicular to the mean direction of the fractures. A DFN model with randomized fracture orientations, on the other hand, lacks an REV for fracture characterization. Therefore, a fracture permeability tensor has to be computed from each element. Modeling of fracture interconnectivity indicates that there exists no preferred direction for hydraulic fracturing to be most effective oweing to the interconnected pathways of the fracture network. 3-D fracture permeability mapping has been applied to the Devonian Chattanooga Shale in Alabama and the results suggest that an

  14. High resolution reservoir geological modelling using outcrop information

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Changmin; Lin Kexiang; Liu Huaibo [Jianghan Petroleum Institute, Hubei (China)] [and others

    1997-08-01

    This is China`s first case study of high resolution reservoir geological modelling using outcrop information. The key of the modelling process is to build a prototype model and using the model as a geological knowledge bank. Outcrop information used in geological modelling including seven aspects: (1) Determining the reservoir framework pattern by sedimentary depositional system and facies analysis; (2) Horizontal correlation based on the lower and higher stand duration of the paleo-lake level; (3) Determining the model`s direction based on the paleocurrent statistics; (4) Estimating the sandbody communication by photomosaic and profiles; (6) Estimating reservoir properties distribution within sandbody by lithofacies analysis; and (7) Building the reservoir model in sandbody scale by architectural element analysis and 3-D sampling. A high resolution reservoir geological model of Youshashan oil field has been built by using this method.

  15. Modeling of Reservoir Inflow for Hydropower Dams Using Artificial ...

    African Journals Online (AJOL)

    The stream flow at the three hydropower reservoirs in Nigeria were modeled using hydro-meteorological parameters and Artificial Neural Network (ANN). The model revealed positive relationship between the observed and the modeled reservoir inflow with values of correlation coefficient of 0.57, 0.84 and 0.92 for Kainji, ...

  16. CarbonSAFE Rocky Mountain Phase I : Seismic Characterization of the Navajo Reservoir, Buzzard Bench, Utah

    Science.gov (United States)

    Haar, K. K.; Balch, R. S.; Lee, S. Y.

    2017-12-01

    The CarbonSAFE Rocky Mountain project team is in the initial phase of investigating the regulatory, financial and technical feasibility of commercial-scale CO2 capture and storage from two coal-fired power plants in the northwest region of the San Rafael Swell, Utah. The reservoir interval is the Jurassic Navajo Sandstone, an eolian dune deposit that at present serves as the salt water disposal reservoir for Ferron Sandstone coal-bed methane production in the Drunkards Wash field and Buzzard Bench area of central Utah. In the study area the Navajo sandstone is approximately 525 feet thick and is at an average depth of about 7000 feet below the surface. If sufficient porosity and permeability exist, reservoir depth and thickness would provide storage for up to 100,000 metric tonnes of CO2 per square mile, based on preliminary estimates. This reservoir has the potential to meet the DOE's requirement of having the ability to store at least 50 million metric tons of CO2 and fulfills the DOE's initiative to develop protocols for commercially sequestering carbon sourced from coal-fired power plants. A successful carbon storage project requires thorough structural and stratigraphic characterization of the reservoir, seal and faults, thereby allowing the creation of a comprehensive geologic model with subsequent simulations to evaluate CO2/brine migration and long-term effects. Target formation lithofacies and subfacies data gathered from outcrop mapping and laboratory analysis of core samples were developed into a geologic model. Synthetic seismic was modeled from this, allowing us to seismically characterize the lithofacies of the target formation. This seismic characterization data was then employed in the interpretation of 2D legacy lines which provided stratigraphic and structural control for more accurate model development of the northwest region of the San Rafael Swell. Developing baseline interpretations such as this are crucial toward long-term carbon storage

  17. Mathematical models of a liquid filtration from reservoirs

    Directory of Open Access Journals (Sweden)

    Anvarbek Meirmanov

    2014-02-01

    Full Text Available This article studies the filtration from reservoirs into porous media under gravity. We start with the exact mathematical model at the microscopic level, describing the joint motion of a liquid in reservoir and the same liquid and the elastic solid skeleton in the porous medium. Then using a homogenization procedure we derive the chain of macroscopic models from the poroelasticity equations up to the simplest Darcy's law in the porous medium and hydraulics in the reservoir.

  18. Reservoir Characterization around Geothermal Field, West Java, Indonesia Derived from 4-D Seismic Tomography

    Science.gov (United States)

    Verdhora Ry, Rexha; Nugraha, A. D.

    2016-01-01

    Observation of micro-seismic events induced by intensive geothermal exploitation in a particular geothermal field, located in West Java region, Indonesia was used to detect the fracture and permeability zone. Using local monitoring seismometer network, tomographic inversions were conducted for the three-dimensional Vp, Vs, and Vp/Vs structure of the reservoir for January - December 2007, January - December 2008, and January - December 2009. First, hypocenters location was relocated using joint hypocenter determination (JHD) method in purpose to estimate best location. Then, seismic tomographic inversions were conducted using delay time tomography for dataset of every year respectively. The travel times passing through the three-dimensional velocity model were calculated using ray tracing pseudo-bending method. Norm and gradient damping were added to constrain blocks without ray and to produce smooth solution model. The inversion algorithm was developed in Matlab environment. Our tomographic inversion results from 3-years of observations indicate the presence of low Vp, low Vs, and low Vp/Vs ratio at depths of about 1 - 3 km below sea level. These features were interpreted may be related to steam-saturated rock in the reservoir area of this geothermal field. The locations of the reservoir area were supported by the data of well- trajectory, where the zones of high Vp/Vs were observed around the injection wells and the zones of low Vp/Vs were observed around the production wells. The extensive low Vp/Vs anomaly that occupies the reservoir is getting stronger during the 3-years study period. This is probably attributed to depletion of pore liquid water in the reservoir and replacement with steam. Continuous monitoring of Vp, Vs, and Vp/Vs is an effective tool for geothermal reservoir characterization and depletion monitoring and can potentially provide information in parts of the reservoir which have not been drilled.

  19. Geological and Petrophysical Characterization of the Ferron Sandstone for 3-D Simulation of a Fluvial-Deltaic Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Chidsey, Jr, Thomas C.

    2001-10-31

    The objective of the Ferron Sandstone project was to develop a comprehensive, interdisciplinary, quantitative characterization f fluvial-deltaic reservoir to allow realistic interwell and reservoir-scale models to be developed for improved oil-field development in similar reservoirs world-wide. Quantitative geological and petrophysical information on the Cretaceous Ferron Sandstone in east-central Utah was collected. Both new and existing data was integrated into a three-dimensional model of spatial variations in porosity, storativity, and tensorial rock permeability at a scale appropriate for inter-well to regional-scale reservoir simulation. Simulation results could improve reservoir management through proper infill and extension drilling strategies, reduction of economic risks, increased recovery from existing oil fields, and more reliable reserve calculations.

  20. Sweet spot identification in underexplored shales using multidisciplinary reservoir characterization and key performance indicators: example of the Posidonia Shale Formation in the Netherlands

    NARCIS (Netherlands)

    Heege, J.H. ter; Zijp, M.H.A.A.; Nelskamp, S.; Douma, L.A.N.R.; Verreussel, R.M.C.H.; Veen, J.H. ten; Bruin, G. de; Peters, M.C.A.M.

    2015-01-01

    Sweet spot identification in underexplored shale gas basins needs to be based on a limited amount of data on shale properties in combination with upfront geological characterization and modelling, because actual production data is usually absent. Multidisciplinary reservoir characterization and

  1. Sweet spot identification in underexplored shales using multidisciplinary reservoir characterization and key performance indicators : Example of the Posidonia Shale Formation in the Netherlands

    NARCIS (Netherlands)

    Ter Heege, Jan; Zijp, Mart; Nelskamp, Susanne; Douma, Lisanne; Verreussel, Roel; Ten Veen, Johan; de Bruin, Geert; Peters, Rene

    2015-01-01

    Sweet spot identification in underexplored shale gas basins needs to be based on a limited amount of data on shale properties in combination with upfront geological characterization and modelling, because actual production data is usually absent. Multidisciplinary reservoir characterization and

  2. Dynamic modeling of surfactant flooding in low permeable argillaceous reservoirs

    Science.gov (United States)

    Kuznetsova, A. N.; Gunkin, A. S.; Rogachev, M. К

    2017-10-01

    This article reveals the current state and problems of the Russian oil production sector. Physicochemical enhanced oil recovery methods are proposed as a solution. The investigation of surfactant treatment efficiency and their integrated effect on oil and reservoir rock is conducted as well as its applicability analysis for low permeable poly-mineral reservoir. The results of dynamic modeling of oil displacement by the developed surfactant composition in a low permeable reservoir are presented.

  3. Modeling Reservoir-River Networks in Support of Optimizing Seasonal-Scale Reservoir Operations

    Science.gov (United States)

    Villa, D. L.; Lowry, T. S.; Bier, A.; Barco, J.; Sun, A.

    2011-12-01

    HydroSCOPE (Hydropower Seasonal Concurrent Optimization of Power and the Environment) is a seasonal time-scale tool for scenario analysis and optimization of reservoir-river networks. Developed in MATLAB, HydroSCOPE is an object-oriented model that simulates basin-scale dynamics with an objective of optimizing reservoir operations to maximize revenue from power generation, reliability in the water supply, environmental performance, and flood control. HydroSCOPE is part of a larger toolset that is being developed through a Department of Energy multi-laboratory project. This project's goal is to provide conventional hydropower decision makers with better information to execute their day-ahead and seasonal operations and planning activities by integrating water balance and operational dynamics across a wide range of spatial and temporal scales. This presentation details the modeling approach and functionality of HydroSCOPE. HydroSCOPE consists of a river-reservoir network model and an optimization routine. The river-reservoir network model simulates the heat and water balance of river-reservoir networks for time-scales up to one year. The optimization routine software, DAKOTA (Design Analysis Kit for Optimization and Terascale Applications - dakota.sandia.gov), is seamlessly linked to the network model and is used to optimize daily volumetric releases from the reservoirs to best meet a set of user-defined constraints, such as maximizing revenue while minimizing environmental violations. The network model uses 1-D approximations for both the reservoirs and river reaches and is able to account for surface and sediment heat exchange as well as ice dynamics for both models. The reservoir model also accounts for inflow, density, and withdrawal zone mixing, and diffusive heat exchange. Routing for the river reaches is accomplished using a modified Muskingum-Cunge approach that automatically calculates the internal timestep and sub-reach lengths to match the conditions of

  4. 3D Geostatistical Modeling and Uncertainty Analysis in a Carbonate Reservoir, SW Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Kamali

    2013-01-01

    Full Text Available The aim of geostatistical reservoir characterization is to utilize wide variety of data, in different scales and accuracies, to construct reservoir models which are able to represent geological heterogeneities and also quantifying uncertainties by producing numbers of equiprobable models. Since all geostatistical methods used in estimation of reservoir parameters are inaccurate, modeling of “estimation error” in form of uncertainty analysis is very important. In this paper, the definition of Sequential Gaussian Simulation has been reviewed and construction of stochastic models based on it has been discussed. Subsequently ranking and uncertainty quantification of those stochastically populated equiprobable models and sensitivity study of modeled properties have been presented. Consequently, the application of sensitivity analysis on stochastic models of reservoir horizons, petrophysical properties, and stochastic oil-water contacts, also their effect on reserve, clearly shows any alteration in the reservoir geometry has significant effect on the oil in place. The studied reservoir is located at carbonate sequences of Sarvak Formation, Zagros, Iran; it comprises three layers. The first one which is located beneath the cap rock contains the largest portion of the reserve and other layers just hold little oil. Simulations show that average porosity and water saturation of the reservoir is about 20% and 52%, respectively.

  5. Surrogate reservoir models for CSI well probabilistic production forecast

    Directory of Open Access Journals (Sweden)

    Saúl Buitrago

    2017-09-01

    Full Text Available The aim of this work is to present the construction and use of Surrogate Reservoir Models capable of accurately predicting cumulative oil production for every well stimulated with cyclic steam injection at any given time in a heavy oil reservoir in Mexico considering uncertain variables. The central composite experimental design technique was selected to capture the maximum amount of information from the model response with a minimum number of reservoir models simulations. Four input uncertain variables (the dead oil viscosity with temperature, the reservoir pressure, the reservoir permeability and oil sand thickness hydraulically connected to the well were selected as the ones with more impact on the initial hot oil production rate according to an analytical production prediction model. Twenty five runs were designed and performed with the STARS simulator for each well type on the reservoir model. The results show that the use of Surrogate Reservoir Models is a fast viable alternative to perform probabilistic production forecasting of the reservoir.

  6. Modeling reservoir geomechanics using discrete element method : Application to reservoir monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Alassi, Haitham Tayseer

    2008-09-15

    Understanding reservoir geomechanical behavior is becoming more and more important for the petroleum industry. Reservoir compaction, which may result in surface subsidence and fault reactivation, occurs during reservoir depletion. Stress changes and possible fracture development inside and outside a depleting reservoir can be monitored using time-lapse (so-called '4D') seismic and/or passive seismic, and this can give valuable information about the conditions of a given reservoir during production. In this study we will focus on using the (particle-based) Discrete Element Method (DEM) to model reservoir geomechanical behavior during depletion and fluid injection. We show in this study that DEM can be used in modeling reservoir geomechanical behavior by comparing results obtained from DEM to those obtained from analytical solutions. The match of the displacement field between DEM and the analytical solution is good, however there is mismatch of the stress field which is related to the way stress is measured in DEM. A good match is however obtained by measuring the stress field carefully. We also use DEM to model reservoir geomechanical behavior beyond the elasticity limit where fractures can develop and faults can reactivate. A general technique has been developed to relate DEM parameters to rock properties. This is necessary in order to use correct reservoir geomechanical properties during modeling. For any type of particle packing there is a limitation that the maximum ratio between P- and S-wave velocity Vp/Vs that can be modeled is 3 . The static behavior for a loose packing is different from the dynamic behavior. Empirical relations are needed for the static behavior based on numerical test observations. The dynamic behavior for both dense and loose packing can be given by analytical relations. Cosserat continuum theory is needed to derive relations for Vp and Vs. It is shown that by constraining the particle rotation, the S-wave velocity can be

  7. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO2 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales

    International Nuclear Information System (INIS)

    Morea, Michael F.

    1999-01-01

    The primary objective of this research is to conduct advanced reservoir characterization and modeling studies in the Antelope Shale reservoir. Characterization studies will be used to determine the technical feasibility of implementing a CO2 enhanced oil recovery project in the Antelope Shale in Buena Vista Hills Field. The Buena Vista Hills pilot CO2 project will demonstrate the economic viability and widespread applicability of CO2 flooding in fractured siliceous shale reservoirs of the San Joaquin Valley. The research consists of four primary work processes: (1) Reservoir Matrix and Fluid Characterization; (2) Fracture characterization; (3) reservoir Modeling and Simulation; and (4) CO2 Pilot Flood and Evaluation. Work done in these areas is subdivided into two phases or budget periods. The first phase of the project will focus on the application of a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work will be used to evaluate how the reservoir will respond to secondary recovery and EOR processes. The second phase of the project will include the implementation and evaluation of an advanced enhanced oil recovery (EOR) pilot in the United Anticline (West Dome) of the Buena Vista Hills Field

  8. Physical Model-Based Investigation of Reservoir Sedimentation Processes

    Directory of Open Access Journals (Sweden)

    Cheng-Chia Huang

    2018-03-01

    Full Text Available Sedimentation is a serious problem in the operations of reservoirs. In Taiwan, the situation became worse after the Chi-Chi Earthquake recorded on 21 September 1999. The sediment trap efficiency in several regional reservoirs has been sharply increased, adversely affecting the operations on water supplies. According to the field record, the average annual sediment deposition observed in several regional reservoirs in Taiwan has been increased. For instance, the typhoon event recorded in 2008 at the Wushe Reservoir, Taiwan, produced a 3 m sediment deposit upstream of the dam. The remaining storage capacity in the Wushe Reservoir was reduced to 35.9% or a volume of 53.79 million m3 for flood water detention in 2010. It is urgent that research should be conducted to understand the sediment movement in the Wushe Reservoir. In this study, a scale physical model was built to reproduce the flood flow through the reservoir, investigate the long-term depositional pattern, and evaluate sediment trap efficiency. This allows us to estimate the residual life of the reservoir by proposing a modification of Brune’s method. It can be presented to predict the lifespan of Taiwan reservoirs due to higher applicability in both the physical model and the observed data.

  9. Reservoir characterization of the Mississippian Ratcliffe, Richland County, Montana, Williston Basin. Topical report, September 1997

    Energy Technology Data Exchange (ETDEWEB)

    Sippel, M.; Luff, K.D.; Hendricks, M.L.

    1998-07-01

    This topical report is a compilation of characterizations by different disciplines of the Mississippian Ratcliffe in portions of Richland County, MT. Goals of the report are to increase understanding of the reservoir rocks, oil-in-place, heterogeneity and methods for improved recovery. The report covers investigations of geology, petrography, reservoir engineering and seismic. The Ratcliffe is a low permeability oil reservoir which appears to be developed across much of the study area and occurs across much of the Williston Basin. The reservoir has not been a primary drilling target in the study area because average reserves have been insufficient to payout the cost of drilling and completion despite the application of hydraulic fracture stimulation. Oil trapping does not appear to be structurally controlled. For the Ratcliffe to be a viable drilling objective, methods need to be developed for (1) targeting better reservoir development and (2) better completions. A geological model is presented for targeting areas with greater potential for commercial reserves in the Ratcliffe. This model can be best utilized with the aid of 3D seismic. A 3D seismic survey was acquired and is used to demonstrate a methodology for targeting the Ratcliffe. Other data obtained during the project include oriented core, special formation-imaging log, pressure transient measurements and oil PVT. Although re-entry horizontal drilling was unsuccessfully tested, this completion technology should improve the economic viability of the Ratcliffe. Reservoir simulation of horizontal completions with productivity of three times that of a vertical well suggested two or three horizontal wells in a 258-ha (640-acre) area could recover sufficient reserves for profitable drilling.

  10. Modelling of Reservoir Operations using Fuzzy Logic and ANNs

    Science.gov (United States)

    Van De Giesen, N.; Coerver, B.; Rutten, M.

    2015-12-01

    Today, almost 40.000 large reservoirs, containing approximately 6.000 km3 of water and inundating an area of almost 400.000 km2, can be found on earth. Since these reservoirs have a storage capacity of almost one-sixth of the global annual river discharge they have a large impact on the timing, volume and peaks of river discharges. Global Hydrological Models (GHM) are thus significantly influenced by these anthropogenic changes in river flows. We developed a parametrically parsimonious method to extract operational rules based on historical reservoir storage and inflow time-series. Managing a reservoir is an imprecise and vague undertaking. Operators always face uncertainties about inflows, evaporation, seepage losses and various water demands to be met. They often base their decisions on experience and on available information, like reservoir storage and the previous periods inflow. We modeled this decision-making process through a combination of fuzzy logic and artificial neural networks in an Adaptive-Network-based Fuzzy Inference System (ANFIS). In a sensitivity analysis, we compared results for reservoirs in Vietnam, Central Asia and the USA. ANFIS can indeed capture reservoirs operations adequately when fed with a historical monthly time-series of inflows and storage. It was shown that using ANFIS, operational rules of existing reservoirs can be derived without much prior knowledge about the reservoirs. Their validity was tested by comparing actual and simulated releases with each other. For the eleven reservoirs modelled, the normalised outflow, , was predicted with a MSE of 0.002 to 0.044. The rules can be incorporated into GHMs. After a network for a specific reservoir has been trained, the inflow calculated by the hydrological model can be combined with the release and initial storage to calculate the storage for the next time-step using a mass balance. Subsequently, the release can be predicted one time-step ahead using the inflow and storage.

  11. Advanced Reservoir Characterization in the Antelope Shale to Establish the Viability of CO2 Enhanced Oil Recovery in California's Monterey Formation Siliceous Shales, Class III

    Energy Technology Data Exchange (ETDEWEB)

    Perri, Pasquale R.; Cooney, John; Fong, Bill; Julander, Dale; Marasigan, Aleks; Morea, Mike; Piceno, Deborah; Stone, Bill; Emanuele, Mark; Sheffield, Jon; Wells, Jeff; Westbrook, Bill; Karnes, Karl; Pearson, Matt; Heisler, Stuart

    2000-04-24

    The primary objective of this project was to conduct advanced reservoir characterization and modeling studies in the Antelope Shale of the Bureau Vista Hills Field. Work was subdivided into two phases or budget periods. The first phase of the project focused on a variety of advanced reservoir characterization techniques to determine the production characteristics of the Antelope Shale reservoir. Reservoir models based on the results of the characterization work would then be used to evaluate how the reservoir would respond to enhanced oil recovery (EOR) processes such as of CO2 flooding. The second phase of the project would be to implement and evaluate a CO2 in the Buena Vista Hills Field. A successful project would demonstrate the economic viability and widespread applicability of CO2 flooding in siliceous shale reservoirs of the San Joaquin Valley.

  12. From eutrophic to mesotrophic: modelling watershed management scenarios to change the trophic status of a reservoir.

    Science.gov (United States)

    Mateus, Marcos; Almeida, Carina; Brito, David; Neves, Ramiro

    2014-03-12

    Management decisions related with water quality in lakes and reservoirs require a combined land-water processes study approach. This study reports on an integrated watershed-reservoir modeling methodology: the Soil and Water Assessment Tool (SWAT) model to estimate the nutrient input loads from the watershed, used afterwards as boundary conditions to the reservoir model, CE-QUAL-W2. The integrated modeling system was applied to the Torrão reservoir and drainage basin. The objective of the study was to quantify the total maximum input load that allows the reservoir to be classified as mesotrophic. Torrão reservoir is located in the Tâmega River, one of the most important tributaries of the Douro River in Portugal. The watershed is characterized by a variety of land uses and urban areas, accounting for a total Waste Water Treatment Plants (WWTP) discharge of ~100,000 p.e. According to the criteria defined by the National Water Institute (based on the WWTP Directive), the Torrão reservoir is classified as eutrophic. Model estimates show that a 10% reduction in nutrient loads will suffice to change the state to mesotrophic, and should target primarily WWTP effluents, but also act on diffuse sources. The method applied in this study should provide a basis for water environmental management decision-making.

  13. Characterization of oil and gas reservoir heterogeneity; Final report, November 1, 1989--June 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, G.D.

    1993-09-01

    The Alaskan North Slope comprises one of the Nation`s and the world`s most prolific oil province. Original oil in place (OOIP) is estimated at nearly 70 BBL (Kamath and Sharma, 1986). Generalized reservoir descriptions have been completed by the University of Alaska`s Petroleum Development Laboratory over North Slope`s major fields. These fields include West Sak (20 BBL OOIP), Ugnu (15 BBL OOIP), Prudhoe Bay (23 BBL OOIP), Kuparuk (5.5 BBL OOIP), Milne Point (3 BBL OOIP), and Endicott (1 BBL OOIP). Reservoir description has included the acquisition of open hole log data from the Alaska Oil and Gas Conservation Commission (AOGCC), computerized well log analysis using state-of-the-art computers, and integration of geologic and logging data. The studies pertaining to fluid characterization described in this report include: experimental study of asphaltene precipitation for enriched gases, CO{sup 2} and West Sak crude system, modeling of asphaltene equilibria including homogeneous as well as polydispersed thermodynamic models, effect of asphaltene deposition on rock-fluid properties, fluid properties of some Alaskan north slope reservoirs. Finally, the last chapter summarizes the reservoir heterogeneity classification system for TORIS and TORIS database.

  14. Producing Light Oil from a Frozen Reservoir: Reservoir and Fluid Characterization of Umiat Field, National Petroleum Reserve, Alaska

    Energy Technology Data Exchange (ETDEWEB)

    Hanks, Catherine

    2012-12-31

    trends. The Lower Grandstand sand consists of two coarsening-upward shoreface sands sequences while the Upper Grandstand consists of a single coarsening-upward shoreface sand. Each of the shoreface sands shows a distinctive permeability profile with high horizontal permeability at the top getting progressively poorer towards the base of the sand. In contrast, deltaic sandstones in the overlying Ninuluk are more permeable at the base of the sands, with decreasing permeability towards the sand top. These trends impart a strong permeability anisotropy to the reservoir and are being incorporated into the reservoir model. These observations also suggest that horizontal wells should target the upper part of the major sands. Natural fractures may superimpose another permeability pattern on the Umiat reservoir that need to be accounted for in both the simulation and in drilling. Examination of legacy core from Umiat field indicate that fractures are present in the subsurface, but don't provide information on their orientation and density. Nearby surface exposures of folds in similar stratigraphy indicate there are at least three possible fracture sets: an early, N/S striking set that may predate folding and two sets possibly related to folding: an EW striking set of extension fractures that are parallel to the fold axes and a set of conjugate shear fractures oriented NE and NW. Analysis of fracture spacing suggests that these natural fractures are fairly widely spaced (25-59 cm depending upon the fracture set), but could provide improved reservoir permeability in horizontal legs drilled perpendicular to the open fracture set. The phase behavior of the Umiat fluid needed to be well understood in order for the reservoir simulation to be accurate. However, only a small amount of Umiat oil was available; this oil was collected in the 1940’s and was severely weathered. The composition of this ‘dead’ Umiat fluid was characterized by gas chromatography. This analysis was

  15. Make use of dynamic data - a constraint based EnKF for SAGD reservoir characterization and production management

    Energy Technology Data Exchange (ETDEWEB)

    Gul, Ali; Nejadi, Siavash; Shah, Sirish L; Trivedi, Japan J [University of Alberta (Canada)

    2011-07-01

    Steam assisted gravity drainage (SAGD) is a thermal recovery process widely used in the Athabasca oil sands, the largest bitumen reservoir in the world. In order to optimize the process, an accurate characterization of the reservoir heterogeneity and identification of the potential steam barriers is necessary. The aim of this paper was to assess the potential of constraint based ensemble Kalman filter (EnKF) approach with localization to address these issues. Data records from observation, production and injection wells were used and the method was tested on a twin well SAGD process and a single well SAGD model with hybrid grids. Results showed a better characterization of the reservoir's heterogeneity and a reduction of uncertainty in the prediction of steam chamber growth. The technique developed herein provides accurate information about the steam chamber and the reservoir heterogeneity and can be used for planning and decision making of other field development strategies.

  16. 3-D Reservoir and Stochastic Fracture Network Modeling for Enhanced Oil Recovery, Circle Ridge Phosphoria/Tensleep Reservoir, and River Reservation, Arapaho and Shoshone Tribes, Wyoming

    Energy Technology Data Exchange (ETDEWEB)

    La Pointe; Paul; Parney, Robert; Eiben, Thorsten; Dunleavy, Mike; Whitney, John

    2002-09-09

    The goal of this project is to improve the recovery of oil from the Circle Ridge Oilfield, located on the Wind River Reservation in Wyoming, through an innovative integration of matrix characterization, structural reconstruction, and the characterization of the fracturing in the reservoir through the use of discrete fracture network models.

  17. Reservoir characterization of the Tertiary Balder field in the Norwegian North Sea

    OpenAIRE

    Ashraf, Fahad

    2013-01-01

    Abstract Reservoir characterization is one of the most important step in exploration and development phases of any prospect. It combines the results of different analyses to reduce the risk and uncertainties and to enhance understanding of reservoirs. In this study an integrated approach; petrophysical analysis, compaction study and rock physics diagnostics is applied to characterize the reservoirs of the Balder field using log data from nine exploration and sixteen appraisal wells. T...

  18. An integrated workflow to characterize and evaluate low resistivity pay and its phenomenon in a sandstone reservoir

    Science.gov (United States)

    Pratama, Edo; Suhaili Ismail, Mohd; Ridha, Syahrir

    2017-06-01

    The identification, characterization and evaluation of low resistivity pay is very challenging and important for the development of oil and gas fields. Proper identification and characterization of these reservoirs is essential for recovering their reserves. There are many reasons for low resistivity pay zones. It is crucial to identify the origin of this phenomenon. This paper deals with the identification, characterization and evaluation of low resistivity hydrocarbon-bearing sand reservoirs in order to understand the low resistivity phenomenon in a sandstone reservoir, the characterization of the rock types and how to conduct petrophysical analysis to accurately obtain petrophysical properties. An integrated workflow based on petrographical, rock typing and petrophysical methods is conducted and applied. From the integrated analysis that was performed, the presence of illite and a mixed layer of illite-smectite clay minerals in sandstone formation and pyrite-siderite conductive minerals was identified as one of the main reasons for low resistivity occurence in sandstone reservoirs. These clay minerals are distributed as a laminated-dispersed shale distribution model in sandstone reservoirs. The dual water method is recommended to calculate water saturation in low resistivity hydrocarbon-bearing sand reservoirs as this method is more accurate and does not result in an over estimation in water saturation calculation.

  19. T-R Cycle Characterization and Imaging: Advanced Diagnostic Methodology for Petroleum Reservoir and Trap Detection and Delineation

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2006-08-30

    Characterization of stratigraphic sequences (T-R cycles or sequences) included outcrop studies, well log analysis and seismic reflection interpretation. These studies were performed by researchers at the University of Alabama, Wichita State University and McGill University. The outcrop, well log and seismic characterization studies were used to develop a depositional sequence model, a T-R cycle (sequence) model, and a sequence stratigraphy predictive model. The sequence stratigraphy predictive model developed in this study is based primarily on the modified T-R cycle (sequence) model. The T-R cycle (sequence) model using transgressive and regressive systems tracts and aggrading, backstepping, and infilling intervals or sections was found to be the most appropriate sequence stratigraphy model for the strata in the onshore interior salt basins of the Gulf of Mexico to improve petroleum stratigraphic trap and specific reservoir facies imaging, detection and delineation. The known petroleum reservoirs of the Mississippi Interior and North Louisiana Salt Basins were classified using T-R cycle (sequence) terminology. The transgressive backstepping reservoirs have been the most productive of oil, and the transgressive backstepping and regressive infilling reservoirs have been the most productive of gas. Exploration strategies were formulated using the sequence stratigraphy predictive model and the classification of the known petroleum reservoirs utilizing T-R cycle (sequence) terminology. The well log signatures and seismic reflector patterns were determined to be distinctive for the aggrading, backstepping and infilling sections of the T-R cycle (sequence) and as such, well log and seismic data are useful for recognizing and defining potential reservoir facies. The use of the sequence stratigraphy predictive model, in combination with the knowledge of how the distinctive characteristics of the T-R system tracts and their subdivisions are expressed in well log patterns

  20. Depositional sequence analysis and sedimentologic modeling for improved prediction of Pennsylvanian reservoirs (Annex 1)

    Energy Technology Data Exchange (ETDEWEB)

    Watney, W.L.

    1992-01-01

    Interdisciplinary studies of the Upper Pennsylvanian Lansing and Kansas City groups have been undertaken in order to improve the geologic characterization of petroleum reservoirs and to develop a quantitative understanding of the processes responsible for formation of associated depositional sequences. To this end, concepts and methods of sequence stratigraphy are being used to define and interpret the three-dimensional depositional framework of the Kansas City Group. The investigation includes characterization of reservoir rocks in oil fields in western Kansas, description of analog equivalents in near-surface and surface sites in southeastern Kansas, and construction of regional structural and stratigraphic framework to link the site specific studies. Geologic inverse and simulation models are being developed to integrate quantitative estimates of controls on sedimentation to produce reconstructions of reservoir-bearing strata in an attempt to enhance our ability to predict reservoir characteristics.

  1. Methodologies for Reservoir Characterization Using Fluid Inclusion Gas Chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Dilley, Lorie M. [Hattenburg Dilley & Linnell, LLC, Anchorage, AL (United States)

    2015-04-13

    The purpose of this project was to: 1) evaluate the relationship between geothermal fluid processes and the compositions of the fluid inclusion gases trapped in the reservoir rocks; and 2) develop methodologies for interpreting fluid inclusion gas data in terms of the chemical, thermal and hydrological properties of geothermal reservoirs. Phase 1 of this project was designed to conduct the following: 1) model the effects of boiling, condensation, conductive cooling and mixing on selected gaseous species; using fluid compositions obtained from geothermal wells, 2) evaluate, using quantitative analyses provided by New Mexico Tech (NMT), how these processes are recorded by fluid inclusions trapped in individual crystals; and 3) determine if the results obtained on individual crystals can be applied to the bulk fluid inclusion analyses determined by Fluid Inclusion Technology (FIT). Our initial studies however, suggested that numerical modeling of the data would be premature. We observed that the gas compositions, determined on bulk and individual samples were not the same as those discharged by the geothermal wells. Gases discharged from geothermal wells are CO2-rich and contain low concentrations of light gases (i.e. H2, He, N, Ar, CH4). In contrast many of our samples displayed enrichments in these light gases. Efforts were initiated to evaluate the reasons for the observed gas distributions. As a first step, we examined the potential importance of different reservoir processes using a variety of commonly employed gas ratios (e.g. Giggenbach plots). The second technical target was the development of interpretational methodologies. We have develop methodologies for the interpretation of fluid inclusion gas data, based on the results of Phase 1, geologic interpretation of fluid inclusion data, and integration of the data. These methodologies can be used in conjunction with the relevant geological and hydrological information on the system to

  2. INCREASING HEAVY OIL RESERVES IN THE WILMINGTON OIL FIELD THROUGH ADVANCED RESERVOIR CHARACTERIZATION AND THERMAL PRODUCTION TECHNOLOGIES

    Energy Technology Data Exchange (ETDEWEB)

    Unknown

    2001-08-08

    The objective of this project is to increase the recoverable heavy oil reserves within sections of the Wilmington Oil Field, near Long Beach, California, through the testing and application of advanced reservoir characterization and thermal production technologies. The hope is that successful application of these technologies will result in their implementation throughout the Wilmington Field and, through technology transfer, will be extended to increase the recoverable oil reserves in other slope and basin clastic (SBC) reservoirs. The existing steamflood in the Tar zone of Fault Block II-A (Tar II-A) has been relatively inefficient because of several producibility problems which are common in SBC reservoirs: inadequate characterization of the heterogeneous turbidite sands, high permeability thief zones, low gravity oil and non-uniform distribution of the remaining oil. This has resulted in poor sweep efficiency, high steam-oil ratios, and early steam breakthrough. Operational problems related to steam breakthrough, high reservoir pressure, and unconsolidated sands have caused premature well and downhole equipment failures. In aggregate, these reservoir and operational constraints have resulted in increased operating costs and decreased recoverable reserves. A suite of advanced reservoir characterization and thermal production technologies are being applied during the project to improve oil recovery and reduce operating costs, including: (1) Development of three-dimensional (3-D) deterministic and stochastic reservoir simulation models--thermal or otherwise--to aid in reservoir management of the steamflood and post-steamflood phases and subsequent development work. (2) Development of computerized 3-D visualizations of the geologic and reservoir simulation models to aid reservoir surveillance and operations. (3) Perform detailed studies of the geochemical interactions between the steam and the formation rock and fluids. (4) Testing and proposed application of a

  3. RESERVOIR CHARACTERIZATION OF UPPER DEVONIAN GORDON SANDSTONE, JACKSONBURG STRINGTOWN OIL FIELD, NORTHWESTERN WEST VIRGINIA

    Energy Technology Data Exchange (ETDEWEB)

    S. Ameri; K. Aminian; K.L. Avary; H.I. Bilgesu; M.E. Hohn; R.R. McDowell; D.L. Matchen

    2001-07-01

    The Jacksonburg-Stringtown oil field contained an estimated 88,500,000 barrels of oil in place, of which approximately 20,000,000 barrels were produced during primary recovery operations. A gas injection project, initiated in 1934, and a pilot waterflood, begun in 1981, yielded additional production from limited portions of the field. The pilot was successful enough to warrant development of a full-scale waterflood in 1990, involving approximately 8,900 acres in three units, with a target of 1,500 barrels of oil per acre recovery. Historical patterns of drilling and development within the field suggests that the Gordon reservoir is heterogeneous, and that detailed reservoir characterization is necessary for understanding well performance and addressing problems observed by the operators. The purpose of this work is to establish relationships among permeability, geophysical and other data by integrating geologic, geophysical and engineering data into an interdisciplinary quantification of reservoir heterogeneity as it relates to production. Conventional stratigraphic correlation and core description shows that the Gordon sandstone is composed of three parasequences, formed along the Late Devonian shoreline of the Appalachian Basin. The parasequences comprise five lithofacies, of which one includes reservoir sandstones. Pay sandstones were found to have permeabilities in core ranging from 10 to 200 mD, whereas non-pay sandstones have permeabilities ranging from below the level of instrumental detection to 5 mD; Conglomeratic zones could take on the permeability characteristics of enclosing materials, or could exhibit extremely low values in pay sandstone and high values in non-pay or low permeability pay sandstone. Four electrofacies based on a linear combination of density and scaled gamma ray best matched correlations made independently based on visual comparison of geophysical logs. Electrofacies 4 with relatively high permeability (mean value > 45 mD) was

  4. Reservoir characterization using core, well log, and seismic data and intelligent software

    Science.gov (United States)

    Soto Becerra, Rodolfo

    We have developed intelligent software, Oilfield Intelligence (OI), as an engineering tool to improve the characterization of oil and gas reservoirs. OI integrates neural networks and multivariate statistical analysis. It is composed of five main subsystems: data input, preprocessing, architecture design, graphics design, and inference engine modules. More than 1,200 lines of programming code as M-files using the language MATLAB been written. The degree of success of many oil and gas drilling, completion, and production activities depends upon the accuracy of the models used in a reservoir description. Neural networks have been applied for identification of nonlinear systems in almost all scientific fields of humankind. Solving reservoir characterization problems is no exception. Neural networks have a number of attractive features that can help to extract and recognize underlying patterns, structures, and relationships among data. However, before developing a neural network model, we must solve the problem of dimensionality such as determining dominant and irrelevant variables. We can apply principal components and factor analysis to reduce the dimensionality and help the neural networks formulate more realistic models. We validated OI by obtaining confident models in three different oil field problems: (1) A neural network in-situ stress model using lithology and gamma ray logs for the Travis Peak formation of east Texas, (2) A neural network permeability model using porosity and gamma ray and a neural network pseudo-gamma ray log model using 3D seismic attributes for the reservoir VLE 196 Lamar field located in Block V of south-central Lake Maracaibo (Venezuela), and (3) Neural network primary ultimate oil recovery (PRUR), initial waterflooding ultimate oil recovery (IWUR), and infill drilling ultimate oil recovery (IDUR) models using reservoir parameters for San Andres and Clearfork carbonate formations in west Texas. In all cases, we compared the results from

  5. Volume 3: Characterization of representative reservoirs -- South Marsh Island 73, B35K and B65G Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Young, M.A.; Salamy, S.P.; Reeves, T.K. [BDM-Oklahoma, Inc., Bartlesville, OK (United States); Kimbrell, W.C. [Louisiana State Univ., Baton Rouge, LA (United States). Dept. of Petroleum Engineering; Sawyer, W.K. [Mathematical and Computer Services, Inc., Danville, VA (United States)

    1998-07-01

    This report documents the results of a detailed study of two Gulf of Mexico salt dome related reservoirs and the application of a publicly available PC-based black oil simulator to model the performances of gas injection processes to recover attic oil. The overall objective of the research project is to assess the oil reserve potential that could result from the application of proven technologies to recover bypassed oil from reservoirs surrounding piercement salt domes in the Gulf of Mexico. The specific study objective was to simulate the primary recovery and attic gas injection performance of the two subject reservoirs to: (1) validate the BOAST model; (2) quantify the attic volume; and (3) predict the attic oil recovery potential that could result from additional updip gas injection. The simulation studies were performed on the B-35K Reservoir and the B-65G Reservoir in the South Marsh Island Block 73 Field using data provided by one of the field operators. A modified PC-version of the BOAST II model was used to match the production and injection performances of these reservoirs in which numerous gas injection cycles had been conducted to recover attic oil. The historical performances of the gas injection cycles performed on both the B-35K Reservoir and B-65G Reservoir were accurately matched, and numerous predictive runs were made to define additional potential for attic oil recovery using gas injection. Predictive sensitivities were conducted to examine the impact of gas injection rate, injection volume, post-injection shut-in time, and the staging of gas injection cycles on oil recovery.

  6. Borehole radar modeling for reservoir monitoring applications

    NARCIS (Netherlands)

    Miorali, M.; Slob, E.C.; Arts, R.J.

    2010-01-01

    The use of down-hole sensors and remotely controlled valves in wells provide enormous benefits to reservoir management and oil production. We suggest borehole radar measurements as a promising technique capable of monitoring the arrival of undesired fluids in the proximity of production wells. The

  7. Application of advanced reservoir characterization, simulation and production optimization strategies to maximize recovery in slope and basin clastic reservoirs, West Texas (Delaware Basin). Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, S.P.; Asquith, G.B.; Barton, M.D.; Cole, A.G.; Gogas, J.; Malik, M.A.; Clift, S.J.; Guzman, J.I.

    1997-11-01

    The objective of this project is to demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost-effective way to recover a higher percentage of the original oil in place through strategic placement of infill wells and geologically based field development. This project involves reservoir characterization of two Late Permian slope and basin clastic reservoirs in the Delaware Basin, West Texas, followed by a field demonstration in one of the fields. The fields being investigated are Geraldine Ford and Ford West fields in Reeves and Culberson Counties, Texas. Project objectives are divided into two major phases, reservoir characterization and implementation. The objectives of the reservoir characterization phase of the project were to provide a detailed understanding of the architecture and heterogeneity of the two fields, the Ford Geraldine unit and Ford West field. Reservoir characterization utilized 3-D seismic data, high-resolution sequence stratigraphy, subsurface field studies, outcrop characterization, and other techniques. Once reservoir characterized was completed, a pilot area of approximately 1 mi{sup 2} at the northern end of the Ford Geraldine unit was chosen for reservoir simulation. This report summarizes the results of the second year of reservoir characterization.

  8. Reservoir Modeling Combining Geostatistics with Markov Chain Monte Carlo Inversion

    DEFF Research Database (Denmark)

    Zunino, Andrea; Lange, Katrine; Melnikova, Yulia

    2014-01-01

    We present a study on the inversion of seismic reflection data generated from a synthetic reservoir model. Our aim is to invert directly for rock facies and porosity of the target reservoir zone. We solve this inverse problem using a Markov chain Monte Carlo (McMC) method to handle the nonlinear,...... constitute samples of the posterior distribution.......We present a study on the inversion of seismic reflection data generated from a synthetic reservoir model. Our aim is to invert directly for rock facies and porosity of the target reservoir zone. We solve this inverse problem using a Markov chain Monte Carlo (McMC) method to handle the nonlinear......, multi-step forward model (rock physics and seismology) and to provide realistic estimates of uncertainties. To generate realistic models which represent samples of the prior distribution, and to overcome the high computational demand, we reduce the search space utilizing an algorithm drawn from...

  9. More Novel Hantaviruses and Diversifying Reservoir Hosts — Time for Development of Reservoir-Derived Cell Culture Models?

    Directory of Open Access Journals (Sweden)

    Isabella Eckerle

    2014-02-01

    Full Text Available Due to novel, improved and high-throughput detection methods, there is a plethora of newly identified viruses within the genus Hantavirus. Furthermore, reservoir host species are increasingly recognized besides representatives of the order Rodentia, now including members of the mammalian orders Soricomorpha/Eulipotyphla and Chiroptera. Despite the great interest created by emerging zoonotic viruses, there is still a gross lack of in vitro models, which reflect the exclusive host adaptation of most zoonotic viruses. The usually narrow host range and genetic diversity of hantaviruses make them an exciting candidate for studying virus-host interactions on a cellular level. To do so, well-characterized reservoir cell lines covering a wide range of bat, insectivore and rodent species are essential. Most currently available cell culture models display a heterologous virus-host relationship and are therefore only of limited value. Here, we review the recently established approaches to generate reservoir-derived cell culture models for the in vitro study of virus-host interactions. These successfully used model systems almost exclusively originate from bats and bat-borne viruses other than hantaviruses. Therefore we propose a parallel approach for research on rodent- and insectivore-borne hantaviruses, taking the generation of novel rodent and insectivore cell lines from wildlife species into account. These cell lines would be also valuable for studies on further rodent-borne viruses, such as orthopox- and arenaviruses.

  10. Three dimensional heat transport modeling in Vossoroca reservoir

    Science.gov (United States)

    Arcie Polli, Bruna; Yoshioka Bernardo, Julio Werner; Hilgert, Stephan; Bleninger, Tobias

    2017-04-01

    Freshwater reservoirs are used for many purposes as hydropower generation, water supply and irrigation. In Brazil, according to the National Energy Balance of 2013, hydropower energy corresponds to 70.1% of the Brazilian demand. Superficial waters (which include rivers, lakes and reservoirs) are the most used source for drinking water supply - 56% of the municipalities use superficial waters as a source of water. The last two years have shown that the Brazilian water and electricity supply is highly vulnerable and that improved management is urgently needed. The construction of reservoirs affects physical, chemical and biological characteristics of the water body, e.g. stratification, temperature, residence time and turbulence reduction. Some water quality issues related to reservoirs are eutrophication, greenhouse gas emission to the atmosphere and dissolved oxygen depletion in the hypolimnion. The understanding of the physical processes in the water body is fundamental to reservoir management. Lakes and reservoirs may present a seasonal behavior and stratify due to hydrological and meteorological conditions, and especially its vertical distribution may be related to water quality. Stratification can control heat and dissolved substances transport. It has been also reported the importance of horizontal temperature gradients, e.g. inflows and its density and processes of mass transfer from shallow to deeper regions of the reservoir, that also may impact water quality. Three dimensional modeling of the heat transport in lakes and reservoirs is an important tool to the understanding and management of these systems. It is possible to estimate periods of large vertical temperature gradients, inhibiting vertical transport and horizontal gradients, which could be responsible for horizontal transport of heat and substances (e.g. differential cooling or inflows). Vossoroca reservoir was constructed in 1949 by the impoundment of São João River and is located near to

  11. Permeability Variation Models for Unsaturated Coalbed Methane Reservoirs

    Directory of Open Access Journals (Sweden)

    Lv Yumin

    2016-05-01

    Full Text Available A large number of models have been established to describe permeability variation with the depletion of reservoir pressure to date. However, no attempt has been made to draw enough attention to the difference in the effect of various factors on permeability variation in different production stages of unsaturated CoalBed Methane (CBM reservoirs. This paper summarizes the existing and common permeability models, determines the relationship between various effects (effective stress effect, matrix shrinkage effect and Klinkenberg effect and desorption characteristics of the recovery of unsaturated CBM reservoirs, then establishes two improved models to quantificationally describe permeability variation, and finally discusses the effects of various factors (gas saturation, cleat porosity, Poisson’s ratio and shrinkage coefficient on permeability variation. The results show that permeability variation during the recovery of unsaturated CBM reservoirs can be divided into two stages: the first one is that permeability variation is only affected by the effective stress effect, and the second is that permeability variation is affected by the combination of the effective stress effect, matrix shrinkage effect and Klinkenberg effect. In the second stage, matrix shrinkage effect and Klinkenberg effect play much more significant role than the effective stress effect, which leads to an increase in permeability with depletion of reservoir pressure. Sensitivity analysis of parameters in the improved models reveals that those parameters associated with gas saturation, such as gas content, reservoir pressure, Langmuir volume and Langmuir pressure, have a significant impact on permeability variation in the first stage, and the important parameters in the second stage are the gas content, reservoir pressure, Langmuir volume, Langmuir pressure, Poisson’s ratio, Young’s modulus and shrinkage coefficient during the depletion of reservoir pressure. A comparative

  12. Outcrop-based reservoir modeling of a naturally fractured siliciclastic CO 2 sequestration site, Svalbard, Arctic Norway

    NARCIS (Netherlands)

    Senger, K.; Ogata, K.; Tveranger, J.; Braathen, A.; Olaussen, S.

    2013-01-01

    We present a geological model of an unconventional siliciclastic reservoir projected for CO2 sequestration near Longyearbyen, Svalbard. The reservoir is characterized by a substantial sub-hydrostatic pressure regime, very low matrix porosity and -permeability values, extensive natural fracturing and

  13. Outcrop-based reservoir modeling of a naturally fractured siliciclastic CO2 sequestration site, Svalbard, Arctic Norway

    NARCIS (Netherlands)

    Senger, K.; Ogata, K.; Tveranger, J.; Braathen, A.; Olaussen, S.

    2013-01-01

    We present a geological model of an unconventional siliciclastic reservoir projected for CO2 sequestration near Longyearbyen, Svalbard. The reservoir is characterized by a substantial sub-hydrostatic pressure regime, very low matrix porosity and -permeability values, extensive natural fracturing and

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

    Energy Technology Data Exchange (ETDEWEB)

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

    1997-08-01

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

  15. Modelling phosphorus retention in lakes and reservoirs

    Czech Academy of Sciences Publication Activity Database

    Hejzlar, Josef; Šámalová, K.; Boers, P.; Kronvang, B.

    2006-01-01

    Roč. 6, 5-6 (2006), s. 487-494 ISSN 1567-7230 R&D Projects: GA AV ČR IAA3017301; GA AV ČR 1QS600170504 Grant - others:EU(XE) EVK1-CT-2001-00096; MSM(CZ) 6007665801 Institutional research plan: CEZ:AV0Z60170517 Keywords : phosphorus * retention * reservoir Subject RIV: DA - Hydrology ; Limnology

  16. Stochastic modeling applied to characterization of Namorado field reservoir (Bacia de Campos - RJ, Brasil); Modelagem estocastica aplicada a caracterizacao do reservatorio de campo de Namorado (Bacia de Campos - RJ, Brasil)

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Caio Graco Pereira; Clennell, Bennedict [Bahia Univ., Salvador, BA (Brazil). Curso de Pos-graduacao em Geofisica]. E-mail: cgps@cpgg.ufba.br; clennell@cpgg.ufba.br; Mato, Luiz Ferradans [PETROBRAS, Salvador, BA (Brazil). Exploracao e Producao]. E-mail: ferradans@petrobras.com.br

    2003-07-01

    The Namorado field is in the centre of the Campos Basin, 70 km from shore, between the 150 and 250 m isobaths. This field is divided into four blocks separated by faults. The main blocks have several levels of turbiditic sands interfingering with shale. The external geometry of the sand bodies is lenticular aligned in the direction NW/SE. The media thickness of the genetic units is 160 m, the thickness of porous sandstones varies from 5 to 105 m. The main faciologic types that occurs in the Namorado field do not have internal structure, leading to poor discrimination of internal characteristics. For application of stochastic modeling to the Namorado reservoir log data and core data, were grouped into reservoir and non-reservoir according to the facies, in addition to the application of the binary discriminant function. The method of simulation used was the Sequential Indicator Simulation. The anisotropy defined was 100:1 in the horizontal direction, the structure has transverse isotropy with a range of 40 m (obtained from the experimental variogram). After several model realizations were averaged, the predicted pattern of reservoir facies distribution (probability of reservoir a quality) were combined, and to correlate well with published sections and other quality indicators. (author)

  17. Sampling from stochastic reservoir models constrained by production data

    Energy Technology Data Exchange (ETDEWEB)

    Hegstad, Bjoern Kaare

    1997-12-31

    When a petroleum reservoir is evaluated, it is important to forecast future production of oil and gas and to assess forecast uncertainty. This is done by defining a stochastic model for the reservoir characteristics, generating realizations from this model and applying a fluid flow simulator to the realizations. The reservoir characteristics define the geometry of the reservoir, initial saturation, petrophysical properties etc. This thesis discusses how to generate realizations constrained by production data, that is to say, the realizations should reproduce the observed production history of the petroleum reservoir within the uncertainty of these data. The topics discussed are: (1) Theoretical framework, (2) History matching, forecasting and forecasting uncertainty, (3) A three-dimensional test case, (4) Modelling transmissibility multipliers by Markov random fields, (5) Up scaling, (6) The link between model parameters, well observations and production history in a simple test case, (7) Sampling the posterior using optimization in a hierarchical model, (8) A comparison of Rejection Sampling and Metropolis-Hastings algorithm, (9) Stochastic simulation and conditioning by annealing in reservoir description, and (10) Uncertainty assessment in history matching and forecasting. 139 refs., 85 figs., 1 tab.

  18. A Study of the Optimal Planning Model for Reservoir Sustainable Management- A Case Study of Shihmen Reservoir

    Science.gov (United States)

    Chen, Y. Y.; Ho, C. C.; Chang, L. C.

    2017-12-01

    The reservoir management in Taiwan faces lots of challenge. Massive sediment caused by landslide were flushed into reservoir, which will decrease capacity, rise the turbidity, and increase supply risk. Sediment usually accompanies nutrition that will cause eutrophication problem. Moreover, the unevenly distribution of rainfall cause water supply instability. Hence, how to ensure sustainable use of reservoirs has become an important task in reservoir management. The purpose of the study is developing an optimal planning model for reservoir sustainable management to find out an optimal operation rules of reservoir flood control and sediment sluicing. The model applies Genetic Algorithms to combine with the artificial neural network of hydraulic analysis and reservoir sediment movement. The main objective of operation rules in this study is to prevent reservoir outflow caused downstream overflow, minimum the gap between initial and last water level of reservoir, and maximum sluicing sediment efficiency. A case of Shihmen reservoir was used to explore the different between optimal operating rule and the current operation of the reservoir. The results indicate optimal operating rules tended to open desilting tunnel early and extend open duration during flood discharge period. The results also show the sluicing sediment efficiency of optimal operating rule is 36%, 44%, 54% during Typhoon Jangmi, Typhoon Fung-Wong, and Typhoon Sinlaku respectively. The results demonstrate the optimal operation rules do play a role in extending the service life of Shihmen reservoir and protecting the safety of downstream. The study introduces a low cost strategy, alteration of operation reservoir rules, into reservoir sustainable management instead of pump dredger in order to improve the problem of elimination of reservoir sediment and high cost.

  19. QUANTITATIVE METHODS FOR RESERVOIR CHARACTERIZATION AND IMPROVED RECOVERY: APPLICATION TO HEAVY OIL SANDS

    Energy Technology Data Exchange (ETDEWEB)

    James W. Castle; Fred J. Molz; Ronald W. Falta; Cynthia L. Dinwiddie; Scott E. Brame; Robert A. Bridges

    2002-10-30

    Improved prediction of interwell reservoir heterogeneity has the potential to increase productivity and to reduce recovery cost for California's heavy oil sands, which contain approximately 2.3 billion barrels of remaining reserves in the Temblor Formation and in other formations of the San Joaquin Valley. This investigation involves application of advanced analytical property-distribution methods conditioned to continuous outcrop control for improved reservoir characterization and simulation, particularly in heavy oil sands. The investigation was performed in collaboration with Chevron Production Company U.S.A. as an industrial partner, and incorporates data from the Temblor Formation in Chevron's West Coalinga Field. Observations of lateral variability and vertical sequences observed in Temblor Formation outcrops has led to a better understanding of reservoir geology in West Coalinga Field. Based on the characteristics of stratigraphic bounding surfaces in the outcrops, these surfaces were identified in the subsurface using cores and logs. The bounding surfaces were mapped and then used as reference horizons in the reservoir modeling. Facies groups and facies tracts were recognized from outcrops and cores of the Temblor Formation and were applied to defining the stratigraphic framework and facies architecture for building 3D geological models. The following facies tracts were recognized: incised valley, estuarine, tide- to wave-dominated shoreline, diatomite, and subtidal. A new minipermeameter probe, which has important advantages over previous methods of measuring outcrop permeability, was developed during this project. The device, which measures permeability at the distal end of a small drillhole, avoids surface weathering effects and provides a superior seal compared with previous methods for measuring outcrop permeability. The new probe was used successfully for obtaining a high-quality permeability data set from an outcrop in southern Utah

  20. Reservoir Modeling Combining Geostatistics with Markov Chain Monte Carlo Inversion

    DEFF Research Database (Denmark)

    Zunino, Andrea; Lange, Katrine; Melnikova, Yulia

    2014-01-01

    We present a study on the inversion of seismic reflection data generated from a synthetic reservoir model. Our aim is to invert directly for rock facies and porosity of the target reservoir zone. We solve this inverse problem using a Markov chain Monte Carlo (McMC) method to handle the nonlinear......, multi-step forward model (rock physics and seismology) and to provide realistic estimates of uncertainties. To generate realistic models which represent samples of the prior distribution, and to overcome the high computational demand, we reduce the search space utilizing an algorithm drawn from...... geostatistics. The geostatistical algorithm learns the multiple-point statistics from prototype models, then generates proposal models which are tested by a Metropolis sampler. The solution of the inverse problem is finally represented by a collection of reservoir models in terms of facies and porosity, which...

  1. Integrating geologic and engineering data into 3-D reservoir models: an example from norman wells field, NWT, Canada

    International Nuclear Information System (INIS)

    Yose, L.A.

    2004-01-01

    A case study of the Norman Wells field will be presented to highlight the work-flow and data integration steps associated with characterization and modeling of a complex hydrocarbon reservoir. Norman Wells is a Devonian-age carbonate bank ('reef') located in the Northwest Territories of Canada, 60 kilometers south of the Arctic Circle. The reservoir reaches a maximum thickness of 130 meters in the reef interior and thins toward the basin due to depositional pinch outs. Norman Wells is an oil reservoir and is currently under a 5-spot water injection scheme for enhanced oil recovery (EOR). EOR strategies require a detailed understanding of how reservoir flow units, flow barriers and flow baffles are distributed to optimize hydrocarbon sweep and recovery and to minimize water handling. Reservoir models are routinely used by industry to characterize the 3-D distribution of reservoir architecture (stratigraphic layers, depositional facies, faults) and rock properties (porosity. permeability). Reservoir models are validated by matching historical performance data (e.g., reservoir pressures, well production or injection rates). Geologic models are adjusted until they produce a history match, and model adjustments are focused on inputs that have the greatest geologic uncertainty. Flow simulation models are then used to optimize field development strategies and to forecast field performance under different development scenarios. (author)

  2. MULTI-ATTRIBUTE SEISMIC/ROCK PHYSICS APPROACH TO CHARACTERIZING FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mavko

    2000-10-01

    This project consists of three key interrelated Phases, each focusing on the central issue of imaging and quantifying fractured reservoirs, through improved integration of the principles of rock physics, geology, and seismic wave propagation. This report summarizes the results of Phase I of the project. The key to successful development of low permeability reservoirs lies in reliably characterizing fractures. Fractures play a crucial role in controlling almost all of the fluid transport in tight reservoirs. Current seismic methods to characterize fractures depend on various anisotropic wave propagation signatures that can arise from aligned fractures. We are pursuing an integrated study that relates to high-resolution seismic images of natural fractures to the rock parameters that control the storage and mobility of fluids. Our goal is to go beyond the current state-of-the art to develop and demonstrate next generation methodologies for detecting and quantitatively characterizing fracture zones using seismic measurements. Our study incorporates 3 key elements: (1) Theoretical rock physics studies of the anisotropic viscoelastic signatures of fractured rocks, including up scaling analysis and rock-fluid interactions to define the factors relating fractures in the lab and in the field. (2) Modeling of optimal seismic attributes, including offset and azimuth dependence of travel time, amplitude, impedance and spectral signatures of anisotropic fractured rocks. We will quantify the information content of combinations of seismic attributes, and the impact of multi-attribute analyses in reducing uncertainty in fracture interpretations. (3) Integration and interpretation of seismic, well log, and laboratory data, incorporating field geologic fracture characterization and the theoretical results of items 1 and 2 above. The focal point for this project is the demonstration of these methodologies in the Marathon Oil Company Yates Field in West Texas.

  3. Optimal Complexity in Reservoir Modeling of an Eolian Sandstone for Carbon Sequestration Simulation

    Science.gov (United States)

    Li, S.; Zhang, Y.; Zhang, X.

    2011-12-01

    Geologic Carbon Sequestration (GCS) is a proposed means to reduce atmospheric concentrations of carbon dioxide (CO2). Given the type, abundance, and accessibility of geologic characterization data, different reservoir modeling techniques can be utilized to build a site model. However, petrophysical properties of a formation can be modeled with simplifying assumptions or with greater detail, the later requiring sophisticated modeling techniques supported by additional data. In GCS where cost of data collection needs to be minimized, will detailed (expensive) reservoir modeling efforts lead to much improved model predictive capability? Is there an optimal level of detail in the reservoir model sufficient for prediction purposes? In Wyoming, GCS into the Nugget Sandstone is proposed. This formation is a deep (>13,000 ft) saline aquifer deposited in eolian environments, exhibiting permeability heterogeneity at multiple scales. Based on a set of characterization data, this study utilizes multiple, increasingly complex reservoir modeling techniques to create a suite of reservoir models including a multiscale, non-stationary heterogeneous model conditioned to a soft depositional model (i.e., training image), a geostatistical (stationary) facies model without conditioning, a geostatistical (stationary) petrophysical model ignoring facies, and finally, a homogeneous model ignoring all aspects of sub-aquifer heterogeneity. All models are built at regional scale with a high-resolution grid (245,133,140 cells) from which a set of local simulation models (448,000 grid cells) are extracted. These are considered alternative conceptual models with which pilot-scale CO2 injection is simulated (50 year duration at 1/10 Mt per year). A computationally efficient sensitivity analysis (SA) is conducted for all models based on a Plackett-Burman Design of Experiment metric. The SA systematically varies key parameters of the models (e.g., variogram structure and principal axes of intrinsic

  4. Depositional sequence analysis and sedimentologic modeling for improved prediction of Pennsylvanian reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Watney, W.L.

    1994-12-01

    Reservoirs in the Lansing-Kansas City limestone result from complex interactions among paleotopography (deposition, concurrent structural deformation), sea level, and diagenesis. Analysis of reservoirs and surface and near-surface analogs has led to developing a {open_quotes}strandline grainstone model{close_quotes} in which relative sea-level stabilized during regressions, resulting in accumulation of multiple grainstone buildups along depositional strike. Resulting stratigraphy in these carbonate units are generally predictable correlating to inferred topographic elevation along the shelf. This model is a valuable predictive tool for (1) locating favorable reservoirs for exploration, and (2) anticipating internal properties of the reservoir for field development. Reservoirs in the Lansing-Kansas City limestones are developed in both oolitic and bioclastic grainstones, however, re-analysis of oomoldic reservoirs provides the greatest opportunity for developing bypassed oil. A new technique, the {open_quotes}Super{close_quotes} Pickett crossplot (formation resistivity vs. porosity) and its use in an integrated petrophysical characterization, has been developed to evaluate extractable oil remaining in these reservoirs. The manual method in combination with 3-D visualization and modeling can help to target production limiting heterogeneities in these complex reservoirs and moreover compute critical parameters for the field such as bulk volume water. Application of this technique indicates that from 6-9 million barrels of Lansing-Kansas City oil remain behind pipe in the Victory-Northeast Lemon Fields. Petroleum geologists are challenged to quantify inferred processes to aid in developing rationale geologically consistent models of sedimentation so that acceptable levels of prediction can be obtained.

  5. Reservoir characterization and final pre-test analysis in support of the compressed-air-energy-storage Pittsfield aquifer field test in Pike County, Illinois

    Energy Technology Data Exchange (ETDEWEB)

    Wiles, L.E.; McCann, R.A.

    1983-06-01

    The work reported is part of a field experimental program to demonstrate and evaluate compressed air energy storage in a porous media aquifer reservoir near Pittsfield, Illinois. The reservoir is described. Numerical modeling of the reservoir was performed concurrently with site development. The numerical models were applied to predict the thermohydraulic performance of the porous media reservoir. This reservoir characterization and pre-test analysis made use of evaluation of bubble development, water coning, thermal development, and near-wellbore desaturation. The work was undertaken to define the time required to develop an air storage bubble of adequate size, to assess the specification of instrumentation and above-ground equipment, and to develop and evaluate operational strategies for air cycling. A parametric analysis was performed for the field test reservoir. (LEW)

  6. 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.

  7. Advanced reservoir characterization and evaluation of CO2 gravity drainage in the naturally fractured Spraberry Trend Area. Annual report, September 1, 1996--August 31, 1997

    Energy Technology Data Exchange (ETDEWEB)

    McDonald, P.

    1998-06-01

    The objective of the Spraberry CO{sub 2} pilot project is to determine the technical and economic feasibility of continuous CO{sub 2} injection in the naturally fractured reservoirs of the Spraberry Trend. In order to describe, understand, and model CO{sub 2} flooding in the naturally fractured Spraberry reservoirs, characterization of the fracture system is a must. Additional reservoir characterization was based on horizontal coring in the second year of the project. In addition to characterization of natural fractures, horizontal coring has confirmed a previously developed rock model for describing the Spraberry Trend shaly sands. A better method for identifying Spraberry pay zones has been verified. The authors have completed the reservoir characterization, which includes matrix description and detection (from core-log integration) and fracture characterization. This information is found in Section 1. The authors have completed extensive imbibition experiments that strongly indicate that the weakly water-wet behavior of the reservoir rock may be responsible for poor waterflood response observed in many Spraberry fields. The authors have also made significant progress in analytical and numerical simulation of performance in Spraberry reservoirs as seen in Section 3. They have completed several suites of CO{sub 2} gravity drainage in Spraberry and Berea whole cores at reservoir conditions and reported in Section 4. The results of these experiments have been useful in developing a model for free-fall gravity drainage and have validated the premise that CO{sub 2} will recover oil from tight, unconfined Spraberry matrix.

  8. Artificial neural network modeling of dissolved oxygen in reservoir.

    Science.gov (United States)

    Chen, Wei-Bo; Liu, Wen-Cheng

    2014-02-01

    The water quality of reservoirs is one of the key factors in the operation and water quality management of reservoirs. Dissolved oxygen (DO) in water column is essential for microorganisms and a significant indicator of the state of aquatic ecosystems. In this study, two artificial neural network (ANN) models including back propagation neural network (BPNN) and adaptive neural-based fuzzy inference system (ANFIS) approaches and multilinear regression (MLR) model were developed to estimate the DO concentration in the Feitsui Reservoir of northern Taiwan. The input variables of the neural network are determined as water temperature, pH, conductivity, turbidity, suspended solids, total hardness, total alkalinity, and ammonium nitrogen. The performance of the ANN models and MLR model was assessed through the mean absolute error, root mean square error, and correlation coefficient computed from the measured and model-simulated DO values. The results reveal that ANN estimation performances were superior to those of MLR. Comparing to the BPNN and ANFIS models through the performance criteria, the ANFIS model is better than the BPNN model for predicting the DO values. Study results show that the neural network particularly using ANFIS model is able to predict the DO concentrations with reasonable accuracy, suggesting that the neural network is a valuable tool for reservoir management in Taiwan.

  9. Model Structure Analysis of Model-based Operation of Petroleum Reservoirs

    NARCIS (Netherlands)

    Van Doren, J.F.M.

    2010-01-01

    The demand for petroleum is expected to increase in the coming decades, while the production of petroleum from subsurface reservoirs is becoming increasingly complex. To meet the demand petroleum reservoirs should be operated more efficiently. Physics-based petroleum reservoir models that describe

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

    Science.gov (United States)

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

    2018-02-01

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

  11. New Heat Flow Models in Fractured Geothermal Reservoirs - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Reis, John

    2001-03-31

    This study developed new analytical models for predicting the temperature distribution within a geothermal reservoir following reinjection of water having a temperature different from that of the reservoir. The study consisted of two parts: developing new analytical models for the heat conduction rate into multi-dimensional, parallelepiped matrix blocks and developing new analytical models for the advance of the thermal front through the geothermal reservoir. In the first part of the study, a number of semi-empirical models for the multi-dimensional heat conduction were developed to overcome the limitations to the exact solutions. The exact solution based on a similarity solution to the heat diffusion equation is the best model for the early-time period, but fails when thermal conduction fronts from opposing sides of the matrix block merge. The exact solution based on an infinite series solution was found not to be useful because it required tens of thousands of terms to be include d for accuracy. The best overall model for the entire conduction time was a semi-empirical model based on an exponential conduction rate. In the second part of the study, the early-time period exact solution based on similarity methods and the semi-empirical exponential model were used to develop new analytical models for the location of the thermal front within the reservoir during injection. These equations were based on an energy balance on the water in the fractured network. These convective models allowed for both dual and triple porosity reservoirs, i.e., one or two independent matrix domains. A method for incorporating measured fracture spacing distributions into these convective models was developed. It was found that there were only minor differences in the predicted areal extent of the heated zone between the dual and triple porosity models. Because of its simplicity, the dual porosity model is recommended. These new models can be used for preliminary reservoir studies

  12. Reservoir characterization of the Smackover Formation in southwest Alabama

    Energy Technology Data Exchange (ETDEWEB)

    Kopaska-Merkel, D.C.; Hall, D.R.; Mann, S.D.; Tew, B.H.

    1993-02-01

    The Upper Jurassic Smackover Formation is found in an arcuate belt in the subsurface from south Texas to panhandle Florida. The Smackover is the most prolific hydrocarbon-producing formation in Alabama and is an important hydrocarbon reservoir from Florida to Texas. In this report Smackover hydrocarbon reservoirs in southwest Alabama are described. Also, the nine enhanced- and improved-recovery projects that have been undertaken in the Smackover of Alabama are evaluated. The report concludes with recommendations about potential future enhanced- and improved-recovery projects in Smackover reservoirs in Alabama and an estimate of the potential volume of liquid hydrocarbons recoverable by enhanced- and improved-recovery methods from the Smackover of Alabama.

  13. Characterization of oil and gas reservoir heterogeneity. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tyler, N.; Barton, M.D.; Bebout, D.G.; Fisher, R.S.; Grigsby, J.D.; Guevara, E.; Holtz, M.; Kerans, C.; Nance, H.S.; Levey, R.A.

    1992-10-01

    Research described In this report addresses the internal architecture of two specific reservoir types: restricted-platform carbonates and fluvial-deltaic sandstones. Together, these two reservoir types contain more than two-thirds of the unrecovered mobile oil remaining ill Texas. The approach followed in this study was to develop a strong understanding of the styles of heterogeneity of these reservoir types based on a detailed outcrop description and a translation of these findings into optimized recovery strategies in select subsurface analogs. Research targeted Grayburg Formation restricted-platform carbonate outcrops along the Algerita Escarpment and In Stone Canyon In southeastern New Mexico and Ferron deltaic sandstones in central Utah as analogs for the North Foster (Grayburg) and Lake Creek (Wilcox) units, respectively. In both settings, sequence-stratigraphic style profoundly influenced between-well architectural fabric and permeability structure. It is concluded that reservoirs of different depositional origins can therefore be categorized Into a ``heterogeneity matrix`` based on varying intensity of vertical and lateral heterogeneity. The utility of the matrix is that it allows prediction of the nature and location of remaining mobile oil. Highly stratified reservoirs such as the Grayburg, for example, will contain a large proportion of vertically bypassed oil; thus, an appropriate recovery strategy will be waterflood optimization and profile modification. Laterally heterogeneous reservoirs such as deltaic distributary systems would benefit from targeted infill drilling (possibly with horizontal wells) and improved areal sweep efficiency. Potential for advanced recovery of remaining mobile oil through heterogeneity-based advanced secondary recovery strategies In Texas is projected to be an Incremental 16 Bbbl. In the Lower 48 States this target may be as much as 45 Bbbl at low to moderate oil prices over the near- to mid-term.

  14. Use of ``rock-typing`` to characterize carbonate reservoir heterogeneity. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ikwuakor, K.C.

    1994-03-01

    The objective of the project was to apply techniques of ``rock-typing`` and quantitative formation evaluation to borehole measurements in order to identify reservoir and non-reservoir rock-types and their properties within the ``C`` zone of the Ordovician Red River carbonates in the northeast Montana and northwest North Dakota areas of the Williston Basin. Rock-typing discriminates rock units according to their pore-size distribution. Formation evaluation estimates porosities and pore fluid saturation. Rock-types were discriminated using crossplots involving three rock-typing criteria: (1) linear relationship between bulk density and porosity, (2) linear relationship between acoustic interval transit-time and porosity, and (3) linear relationship between acoustic interval transit-time and bulk density. Each rock-type was quantitatively characterized by the slopes and intercepts established for different crossplots involving the above variables, as well as porosities and fluid saturations associated with the rock-types. All the existing production was confirmed through quantitative formation evaluation. Highly porous dolomites and anhydritic dolomites contribute most of the production, and constitute the best reservoir rock-types. The results of this study can be applied in field development and in-fill drilling. Potential targets would be areas of porosity pinchouts and those areas where highly porous zones are downdip from non-porous and tight dolomites. Such areas are abundant. In order to model reservoirs for enhanced oil recovery (EOR) operations, a more localized (e.g. field scale) study, expanded to involve other rock-typing criteria, is necessary.

  15. Application of the ensemble Kalman filter for characterization and history matching of unconventional oil reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Chitralekha, S.B.; Trivedi, J.J.; Shah, S.L. [Alberta Univ., Edmonton, AB (Canada)

    2010-07-01

    The ensemble Kalman filter (EnKF) was used to continuously update and history match the petroleum reservoir characteristics of 2 unconventional oil reservoir models, notably (1) a highly heterogenous black oil reservoir model, and (2) a heterogenous steam assisted gravity drainage (SAGD) reservoir model. The method was used to sequentially update the spatial properties of the reservoir models through the integration of dynamic production data. Monte Carlo simulations of the model ensembles were used. The method considered production uncertainty by using error covariance matrices for measurement and state vectors. Results of the study demonstrated the advantages of using a localized EnKF for effective history matching. Significant computational time was saved by running the ensemble simulations on independent processors in a parallel mode. 28 refs., 16 figs.

  16. Generation of reservoir models on flexible meshes; Generation de modeles de reservoir sur maillage flexible

    Energy Technology Data Exchange (ETDEWEB)

    Ricard, L.

    2005-12-15

    The high level geo-statistic description of the subsurface are often far too detailed for use in routine flow simulators. To make flow simulations tractable, the number of grid blocks has to be reduced: an approximation, still relevant with flow description, is necessary. In this work, we place the emphasis on the scaling procedure from the fine scale model to the multi-scale reservoir model. Two main problems appear: Near wells, faults and channels, the volume of flexible cells may be less than fine ones, so we need to solve a down-scaling problem; Far from these regions, the volume of cells are bigger than fine ones so we need to solve an up-scaling problem. In this work, research has been done on each of these three areas: down-scaling, up-scaling and fluid flow simulation. For each of these subjects, a review, some news improvements and comparative study are proposed. The proposed down-scaling method is build to be compatible with existing data integration methods. The comparative study shows that empirical methods are not enough accurate to solve the problem. Concerning the up-scaling step, the proposed approach is based on an existing method: the perturbed boundary conditions. An extension to unstructured mesh is developed for the inter-cell permeability tensor. The comparative study shows that numerical methods are not always as accurate as expected and the empirical model can be sufficient in lot of cases. A new approach to single-phase fluid flow simulation is developed. This approach can handle with full tensorial permeability fields with source or sink terms.(author)

  17. Open System Models of Isotopic Evolution in Earth's Silicate Reservoirs

    Science.gov (United States)

    Kumari, S.; Paul, D.; Stracke, A.

    2016-12-01

    The present-day elemental and isotopic composition of Earth's terrestrial reservoirs can be used as geochemical constraints to study evolution of the crust-mantle system. A flexible open system evolutionary model of the Earth, comprising continental crust (CC), upper depleted mantle (UM) -source of mid-ocean ridge basalts (MORB), and lower mantle (LM) reservoir with an isolated reservoir-source of ocean island basalts (OIB), and incorporating key radioactive isotope systematics (Rb-Sr, Sm-Nd, and U-Th-Pb), is solved numerically at 1 Ma time step for 4.55 Ga, the age of the Earth. The best possible model-derived solution is the one that produces the present-day concentrations as well as isotopic ratios in terrestrial reservoirs, constrained from published data. Various crustal growth scenarios (continuous versus episodic and early versus late) and its effect on the evolution of isotope systematics in the silicate reservoirs have been evaluated. Modeling results suggest that a whole mantle that is compositionally similar to the present-day MORB source is not consistent with observational constraints. However, a heterogeneous mantle model, in which the present-day UM is 60% of the total mantle mass and a lower non-chondritic mantle, reproduces the estimated isotopic ratios and abundances in Earth's silicate reservoirs. Our results shows that mode of crustal growth strongly affects isotopic evolution of silicate Earth; only an exponential crustal growth pattern satisfactorily explains the chemical and isotopic evolution of the crust-mantle system. One notable feature of successful models is an early depletion of incompatible elements (and a rapid decrease in Th/U ratio, κ, in the UM) by the initial 500 Ma, as a result of early formation of continental crust. Assuming a slightly younger age of the Earth (4.45 Ga), our model better satisfies the Pb-isotope systematics in the respective silicate reservoirs, particularly in the UM, and explains the origin of several OIBs

  18. Reservoir Characterization using Seismic and Well Logs Data (A ...

    African Journals Online (AJOL)

    During analysis, hydrocarbon saturation in relatively unconsolidated sandstone reservoirs is a pore fluid property that has been successfully mapped using seismic surveys. The presence of hydrocarbon typically lowers the seismic velocity and density of unconsolidated to moderately consolidated sandstone and this in turn ...

  19. Reservoir monitoring and characterization for heavy-oil thermal recovery

    Energy Technology Data Exchange (ETDEWEB)

    Pankaj, P.; Pathak, V. [Indian School of Mines (India)

    2005-11-01

    Cyclic steam stimulation (CSS) techniques can become uneconomical in their later cycles, as the oil to steam ratio can drop significantly. Time-lapse seismic assisted follow-up programs can improve oil to steam ratios and production rates within 1 cycle. This study presented the results of an optimized quantitative cross-calibration and cross-training stream that was developed for time-lapse seismic data analysis using data normalization as a bridge. It was anticipated that the stream would provide more consistent results than independent training for reservoir monitoring. In order to compensate for the redundancy of conventional seismic attributes, seismic attributes calculated from principal component decomposition of the seismic data were developed and used for reservoir monitoring. Time-lapse data sets were analyzed by the merging of 2 data sets. Attributes were calculated separately from individual surveys. A significant improvement was noted on time lapse data analysis. Post-stack inversion was applied to time lapse data sets, as the time lapse data normalization was no longer required because the wavelets were extracted independently from each data set. Vertical conformance revealed that sequence architecture had a significant influence on steam migration. A sequence with a high mud content limited both the vertical and horizontal migration of the steam chamber. It was determined that the functional relation of P- to S- wave velocities played an important role in extracting S-wave information from pre-stack data. The mud-rock line established from in-situ P- and S- wave velocity measurements was optimized for Cold Lake clastic rocks. It was concluded that with an optimized mud-rock line and high frequency seismic data, reservoir heterogeneity can be well defined by fluid factor. When applied to reservoir monitoring, this method defined steam channels and successfully identified lithological barriers within the reservoir. 5 refs., 7 figs.

  20. Characterization of reservoir-type microcapsules made by the solvent exchange method.

    Science.gov (United States)

    Yeo, Yoon; Park, Kinam

    2004-09-17

    The purpose of this research was to characterize and optimize the properties of microcapsules produced by the solvent exchange method, a new microencapsulation technique. Reservoir-type microcapsules containing lysozyme as a model protein were produced using a coaxial ultrasonic atomizer under various formulation and instrument settings, and characterized with respect to in vitro release kinetics and stability of the encapsulated protein. The solvent exchange method could encapsulate protein drugs with high efficiency under an optimized condition and was mild enough to preserve the integrity of the encapsulated lysozyme during the process. In vitro release studies showed that the microcapsules could release proteins in a controllable manner. The solvent exchange method is a mild and simple microencapsulation method that could encapsulate lysozyme, maintaining its functional integrity.

  1. Characterization of oil and gas reservoirs and recovery technology deployment on Texas State Lands

    Energy Technology Data Exchange (ETDEWEB)

    Tyler, R.; Major, R.P.; Holtz, M.H. [Univ. of Texas, Austin, TX (United States)] [and others

    1997-08-01

    Texas State Lands oil and gas resources are estimated at 1.6 BSTB of remaining mobile oil, 2.1 BSTB, or residual oil, and nearly 10 Tcf of remaining gas. An integrated, detailed geologic and engineering characterization of Texas State Lands has created quantitative descriptions of the oil and gas reservoirs, resulting in delineation of untapped, bypassed compartments and zones of remaining oil and gas. On Texas State Lands, the knowledge gained from such interpretative, quantitative reservoir descriptions has been the basis for designing optimized recovery strategies, including well deepening, recompletions, workovers, targeted infill drilling, injection profile modification, and waterflood optimization. The State of Texas Advanced Resource Recovery program is currently evaluating oil and gas fields along the Gulf Coast (South Copano Bay and Umbrella Point fields) and in the Permian Basin (Keystone East, Ozona, Geraldine Ford and Ford West fields). The program is grounded in advanced reservoir characterization techniques that define the residence of unrecovered oil and gas remaining in select State Land reservoirs. Integral to the program is collaboration with operators in order to deploy advanced reservoir exploitation and management plans. These plans are made on the basis of a thorough understanding of internal reservoir architecture and its controls on remaining oil and gas distribution. Continued accurate, detailed Texas State Lands reservoir description and characterization will ensure deployment of the most current and economically viable recovery technologies and strategies available.

  2. Well testing in gas hydrate reservoirs

    OpenAIRE

    Kome, Melvin Njumbe

    2015-01-01

    Reservoir testing and analysis are fundamental tools in understanding reservoir hydraulics and hence forecasting reservoir responses. The quality of the analysis is very dependent on the conceptual model used in investigating the responses under different flowing conditions. The use of reservoir testing in the characterization and derivation of reservoir parameters is widely established, especially in conventional oil and gas reservoirs. However, with depleting conventional reserves, the ...

  3. Nonlinear Model Predictive Control for Oil Reservoirs Management

    DEFF Research Database (Denmark)

    Capolei, Andrea

    . The controller consists of -A model based optimizer for maximizing some predicted financial measure of the reservoir (e.g. the net present value). -A parameter and state estimator. -Use of the moving horizon principle for data assimilation and implementation of the computed control input. The optimizer uses...... Optimization has been suggested to compensate for inherent geological uncertainties in an oil field. In robust optimization of an oil reservoir, the water injection and production borehole pressures are computed such that the predicted net present value of an ensemble of permeability field realizations...... equivalent strategy is not justified for the particular case studied in this paper. The third contribution of this thesis is a mean-variance method for risk mitigation in production optimization of oil reservoirs. We introduce a return-risk bicriterion objective function for the profit-risk tradeoff...

  4. Design and modeling of reservoir operation strategies for sediment management

    NARCIS (Netherlands)

    Sloff, C.J.; Omer, A.Y.A.; Heynert, K.V.; Mohamed, Y.A.

    2015-01-01

    Appropriate operation strategies that allow for sediment flushing and sluicing (sediment routing) can reduce rapid storage losses of (hydropower and water-supply) reservoirs. In this study we have shown, using field observations and computational models, that the efficiency of these operations

  5. Bacterial diversity characterization in petroleum samples from Brazilian reservoirs

    Science.gov (United States)

    de Oliveira, Valéria Maia; Sette, Lara Durães; Simioni, Karen Christina Marques; dos Santos Neto, Eugênio Vaz

    2008-01-01

    This study aimed at evaluating potential differences among the bacterial communities from formation water and oil samples originated from biodegraded and non-biodegraded Brazilian petroleum reservoirs by using a PCR-DGGE based approach. Environmental DNA was isolated and used in PCR reactions with bacterial primers, followed by separation of 16S rDNA fragments in the DGGE. PCR products were also cloned and sequenced, aiming at the taxonomic affiliation of the community members. The fingerprints obtained allowed the direct comparison among the bacterial communities from oil samples presenting distinct degrees of biodegradation, as well as between the communities of formation water and oil sample from the non-biodegraded reservoir. Very similar DGGE band profiles were observed for all samples, and the diversity of the predominant bacterial phylotypes was shown to be low. Cloning and sequencing results revealed major differences between formation water and oil samples from the non-biodegraded reservoir. Bacillus sp. and Halanaerobium sp. were shown to be the predominant components of the bacterial community from the formation water sample, whereas the oil sample also included Alicyclobacillus acidoterrestris, Rhodococcus sp., Streptomyces sp. and Acidithiobacillus ferrooxidans. The PCR-DGGE technique, combined with cloning and sequencing of PCR products, revealed the presence of taxonomic groups not found previously in these samples when using cultivation-based methods and 16S rRNA gene library assembly, confirming the need of a polyphasic study in order to improve the knowledge of the extent of microbial diversity in such extreme environments. PMID:24031244

  6. Reservoir characterization based on tracer response and rank analysis of production and injection rates

    Energy Technology Data Exchange (ETDEWEB)

    Refunjol, B.T. [Lagoven, S.A., Pdvsa (Venezuela); Lake, L.W. [Univ. of Texas, Austin, TX (United States)

    1997-08-01

    Quantification of the spatial distribution of properties is important for many reservoir-engineering applications. But, before applying any reservoir-characterization technique, the type of problem to be tackled and the information available should be analyzed. This is important because difficulties arise in reservoirs where production records are the only information for analysis. This paper presents the results of a practical technique to determine preferential flow trends in a reservoir. The technique is a combination of reservoir geology, tracer data, and Spearman rank correlation coefficient analysis. The Spearman analysis, in particular, will prove to be important because it appears to be insightful and uses injection/production data that are prevalent in circumstances where other data are nonexistent. The technique is applied to the North Buck Draw field, Campbell County, Wyoming. This work provides guidelines to assess information about reservoir continuity in interwell regions from widely available measurements of production and injection rates at existing wells. The information gained from the application of this technique can contribute to both the daily reservoir management and the future design, control, and interpretation of subsequent projects in the reservoir, without the need for additional data.

  7. Selecting an Appropriate Upscaled Reservoir Model Based on Connectivity Analysis

    Directory of Open Access Journals (Sweden)

    Preux Christophe

    2016-09-01

    Full Text Available Reservoir engineers aim to build reservoir models to investigate fluid flows within hydrocarbon reservoirs. These models consist of three-dimensional grids populated by petrophysical properties. In this paper, we focus on permeability that is known to significantly influence fluid flow. Reservoir models usually encompass a very large number of fine grid blocks to better represent heterogeneities. However, performing fluid flow simulations for such fine models is extensively CPU-time consuming. A common practice consists in converting the fine models into coarse models with less grid blocks: this is the upscaling process. Many upscaling methods have been proposed in the literature that all lead to distinct coarse models. The problem is how to choose the appropriate upscaling method. Various criteria have been established to evaluate the information loss due to upscaling, but none of them investigate connectivity. In this paper, we propose to first perform a connectivity analysis for the fine and candidate coarse models. This makes it possible to identify shortest paths connecting wells. Then, we introduce two indicators to quantify the length and trajectory mismatch between the paths for the fine and the coarse models. The upscaling technique to be recommended is the one that provides the coarse model for which the shortest paths are the closest to the shortest paths determined for the fine model, both in terms of length and trajectory. Last, the potential of this methodology is investigated from two test cases. We show that the two indicators help select suitable upscaling techniques as long as gravity is not a prominent factor that drives fluid flows.

  8. Integrated reservoir characterization and oil in place estimation for Ayacucho area, Orinoco oil belt, Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, E.; Bauza, I.; Cadena, A. [Petroleos de Venezuela S.A. (Venezuela)

    2008-07-01

    This paper presented the results of a study that investigated the reservoir rock and fluid properties of the main formations in the Orinoco Oil Belt. The four major areas of the basin include the Boyaca, Junin, Ayacucho and Carabobo. An integrated reservoir model based on geological analysis, petrophysics, 2D seismic, fluid analysis, 3D Geocellular modeling was developed to characterize the Ayacucho area, in which oil traps are mainly stratigraphic in the lowermost sand-bodies of Oficina Formation. The main oil bearing intervals are sand beds of the basal part of the formation. Five major geological zones have been identified in the Oficina Formation based on sequence stratigraphy, lithology and facies change, core description, and log-derived properties. The uppermost part of the Oficina Formation (zone A) has the most extensive indications of marine influence in its strata succession. The sandstone beds of the middle part (zone B) are massive to cross bedded and have been deposited in shoreline. Zones C and D are composed of shale, siltstone, mudstone, coaly beds, and sand-bodies, and are the depositional product of tide-dominated coastal plain settings. The main reservoir is located in the lowermost sand-bodies of the formation. The main oil bearing intervals are sand beds of the basal part of the formation, namely zones E. These sand-bodies were deposited in a braided fluvial setting. The oil bearing zones thicknesses are variable and most of the faults are normal and oriented east-west. It was concluded that the Oficina Formation in Ayacucho contains 166 MMMSTB of original oil in place. The average viscosity value for Ayacucho is estimated at 5000 cp. decreasing from south to north. 14 refs., 2 tabs., 18 figs.

  9. A location-based multiple point statistics method: modelling the reservoir with non-stationary characteristics

    Science.gov (United States)

    Yin, Yanshu; Feng, Wenjie

    2017-12-01

    In this paper, a location-based multiple point statistics method is developed to model a non-stationary reservoir. The proposed method characterizes the relationship between the sedimentary pattern and the deposit location using the relative central position distance function, which alleviates the requirement that the training image and the simulated grids have the same dimension. The weights in every direction of the distance function can be changed to characterize the reservoir heterogeneity in various directions. The local integral replacements of data events, structured random path, distance tolerance and multi-grid strategy are applied to reproduce the sedimentary patterns and obtain a more realistic result. This method is compared with the traditional Snesim method using a synthesized 3-D training image of Poyang Lake and a reservoir model of Shengli Oilfield in China. The results indicate that the new method can reproduce the non-stationary characteristics better than the traditional method and is more suitable for simulation of delta-front deposits. These results show that the new method is a powerful tool for modelling a reservoir with non-stationary characteristics.

  10. 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.

  11. Local Refinement of the Super Element Model of Oil Reservoir

    Directory of Open Access Journals (Sweden)

    A.B. Mazo

    2017-12-01

    Full Text Available In this paper, we propose a two-stage method for petroleum reservoir simulation. The method uses two models with different degrees of detailing to describe hydrodynamic processes of different space-time scales. At the first stage, the global dynamics of the energy state of the deposit and reserves is modeled (characteristic scale of such changes is km / year. The two-phase flow equations in the model of global dynamics operate with smooth averaged pressure and saturation fields, and they are solved numerically on a large computational grid of super-elements with a characteristic cell size of 200-500 m. The tensor coefficients of the super-element model are calculated using special procedures of upscaling of absolute and relative phase permeabilities. At the second stage, a local refinement of the super-element model is constructed for calculating small-scale processes (with a scale of m / day, which take place, for example, during various geological and technical measures aimed at increasing the oil recovery of a reservoir. Then we solve the two-phase flow problem in the selected area of the measure exposure on a detailed three-dimensional grid, which resolves the geological structure of the reservoir, and with a time step sufficient for describing fast-flowing processes. The initial and boundary conditions of the local problem are formulated on the basis of the super-element solution. This approach allows us to reduce the computational costs in order to solve the problems of designing and monitoring the oil reservoir. To demonstrate the proposed approach, we give an example of the two-stage modeling of the development of a layered reservoir with a local refinement of the model during the isolation of a water-saturated high-permeability interlayer. We show a good compliance between the locally refined solution of the super-element model in the area of measure exposure and the results of numerical modeling of the whole history of reservoir

  12. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2002-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 2 of the project has been reservoir characterization, 3-D modeling and technology transfer. This effort has included six tasks: (1) the study of rockfluid interactions, (2) petrophysical and engineering characterization, (3) data integration, (4) 3-D geologic modeling, (5) 3-D reservoir simulation and (6) technology transfer. This work was scheduled for completion in Year 2. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions is near completion. Observations regarding the diagenetic processes influencing pore system development and

  13. APPLICATION OF RESERVOIR CHARACTERIZATION AND ADVANCED TECHNOLOGY TO IMPROVE RECOVERY AND ECONOMICS IN A LOWER QUALITY SHALLOW SHELF SAN ANDRES RESERVOIR

    International Nuclear Information System (INIS)

    Kumar, Raj; Keith Brown; Hickman, Scott T.; Justice, James J.

    2000-01-01

    The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs. Therefore, the majority of Budget Period 1 was devoted to reservoir characterization. Technologies being demonstrated include: (1) Advanced petrophysics; (2) Three-dimensional (3-D) seismic; (3) Crosswell bore tomography; (4) Advanced reservoir simulation; (5) Carbon dioxide (CO 2 ) stimulation treatments; (6) Hydraulic fracturing design and monitoring; and (7) Mobility control agents

  14. APPLICATION OF RESERVOIR CHARACTERIZATION AND ADVANCED TECHNOLOGY TO IMPROVE RECOVERY AND ECONOMICS IN A LOWER QUALITY SHALLOW SHELF SAN ANDRES RESERVOIR

    Energy Technology Data Exchange (ETDEWEB)

    T. Scott Hickman; James J. Justice

    2001-06-16

    The Class 2 Project at West Welch was designed to demonstrate the use of advanced technologies to enhance the economics of improved oil recovery (IOR) projects in lower quality Shallow Shelf Carbonate (SSC) reservoirs, resulting in recovery of additional oil that would otherwise be left in the reservoir at project abandonment. Accurate reservoir description is critical to the effective evaluation and efficient design of IOR projects in the heterogeneous SSC reservoirs. Therefore, the majority of Budget Period 1 was devoted to reservoir characterization. Technologies being demonstrated include: (1) Advanced petrophysics; (2) Three-dimensional (3-D) seismic; (3) Crosswell bore tomography; (4) Advanced reservoir simulation; (5) Carbon dioxide (CO{sub 2}) stimulation treatments; (6) Hydraulic fracturing design and monitoring; and (7) Mobility control agents.

  15. Evaluation of field development plans using 3-D reservoir modelling

    Energy Technology Data Exchange (ETDEWEB)

    Seifert, D.; Lewis, J.J.M. [Heriot-Watt Univ., Edinburgh (United Kingdom); Newbery, J.D.H. [Conoco, UK Ltd., Aberdeen (United Kingdom)] [and others

    1997-08-01

    Three-dimensional reservoir modelling has become an accepted tool in reservoir description and is used for various purposes, such as reservoir performance prediction or integration and visualisation of data. In this case study, a small Northern North Sea turbiditic reservoir was to be developed with a line drive strategy utilising a series of horizontal producer and injector pairs, oriented north-south. This development plan was to be evaluated and the expected outcome of the wells was to be assessed and risked. Detailed analyses of core, well log and analogue data has led to the development of two geological {open_quotes}end member{close_quotes} scenarios. Both scenarios have been stochastically modelled using the Sequential Indicator Simulation method. The resulting equiprobable realisations have been subjected to detailed statistical well placement optimisation techniques. Based upon bivariate statistical evaluation of more than 1000 numerical well trajectories for each of the two scenarios, it was found that the wells inclinations and lengths had a great impact on the wells success, whereas the azimuth was found to have only a minor impact. After integration of the above results, the actual well paths were redesigned to meet external drilling constraints, resulting in substantial reductions in drilling time and costs.

  16. 3D architecture modeling of reservoir compartments in a Shingled Turbidite Reservoir using high-resolution seismic data and sparse well control, example from Mars {open_quotes}Pink{close_quotes} reservoir, Mississippi Canyon Area, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Chapin, M.A.; Mahaffie, M.J.; Tiller, G.M. [Shell Exploration and Production Technology Co., Houston, TX (United States)

    1996-12-31

    Economics of most deep-water development projects require large reservoir volumes to be drained with relatively few wells. The presence of reservoir compartments must therefore be detected and planned for in a pre-development stage. We have used 3-D seismic data to constrain large-scale, deterministic reservoir bodies in a 3-D architecture model of Pliocene-turbidite sands of the {open_quotes}E{close_quotes} or {open_quotes}Pink{close_quotes} reservoir, Prospect Mars, Mississippi Canyon Areas 763 and 807, Gulf of Mexico. Reservoir compartmentalization is influenced by stratigraphic shingling, which in turn is caused by low accommodation space predentin the upper portion of a ponded seismic sequence within a salt withdrawal mini-basin. The accumulation is limited by updip onlap onto a condensed section marl, and by lateral truncation by a large scale submarine erosion surface. Compartments were suggested by RFT pressure variations and by geochemical analysis of RFT fluid samples. A geological interpretation derived from high-resolution 3-D seismic and three wells was linked to 3-D architecture models through seismic inversion, resulting in a reservoir all available data. Distinguishing subtle stratigraphical shingles from faults was accomplished by detailed, loop-level mapping, and was important to characterize the different types of reservoir compartments. Seismic inversion was used to detune the seismic amplitude, adjust sandbody thickness, and update the rock properties. Recent development wells confirm the architectural style identified. This modeling project illustrates how high-quality seismic data and architecture models can be combined in a pre-development phase of a prospect, in order to optimize well placement.

  17. 3D architecture modeling of reservoir compartments in a Shingled Turbidite Reservoir using high-resolution seismic data and sparse well control, example from Mars [open quotes]Pink[close quotes] reservoir, Mississippi Canyon Area, Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Chapin, M.A.; Mahaffie, M.J.; Tiller, G.M. (Shell Exploration and Production Technology Co., Houston, TX (United States))

    1996-01-01

    Economics of most deep-water development projects require large reservoir volumes to be drained with relatively few wells. The presence of reservoir compartments must therefore be detected and planned for in a pre-development stage. We have used 3-D seismic data to constrain large-scale, deterministic reservoir bodies in a 3-D architecture model of Pliocene-turbidite sands of the [open quotes]E[close quotes] or [open quotes]Pink[close quotes] reservoir, Prospect Mars, Mississippi Canyon Areas 763 and 807, Gulf of Mexico. Reservoir compartmentalization is influenced by stratigraphic shingling, which in turn is caused by low accommodation space predentin the upper portion of a ponded seismic sequence within a salt withdrawal mini-basin. The accumulation is limited by updip onlap onto a condensed section marl, and by lateral truncation by a large scale submarine erosion surface. Compartments were suggested by RFT pressure variations and by geochemical analysis of RFT fluid samples. A geological interpretation derived from high-resolution 3-D seismic and three wells was linked to 3-D architecture models through seismic inversion, resulting in a reservoir all available data. Distinguishing subtle stratigraphical shingles from faults was accomplished by detailed, loop-level mapping, and was important to characterize the different types of reservoir compartments. Seismic inversion was used to detune the seismic amplitude, adjust sandbody thickness, and update the rock properties. Recent development wells confirm the architectural style identified. This modeling project illustrates how high-quality seismic data and architecture models can be combined in a pre-development phase of a prospect, in order to optimize well placement.

  18. A simple multistage closed-(box+reservoir model of chemical evolution

    Directory of Open Access Journals (Sweden)

    Caimmi R.

    2011-01-01

    Full Text Available Simple closed-box (CB models of chemical evolution are extended on two respects, namely (i simple closed-(box+reservoir (CBR models allowing gas outflow from the box into the reservoir (Hartwick 1976 or gas inflow into the box from the reservoir (Caimmi 2007 with rate proportional to the star formation rate, and (ii simple multistage closed-(box+reservoir (MCBR models allowing different stages of evolution characterized by different inflow or outflow rates. The theoretical differential oxygen abundance distribution (TDOD predicted by the model maintains close to a continuous broken straight line. An application is made where a fictitious sample is built up from two distinct samples of halo stars and taken as representative of the inner Galactic halo. The related empirical differential oxygen abundance distribution (EDOD is represented, to an acceptable extent, as a continuous broken line for two viable [O/H]-[Fe/H] empirical relations. The slopes and the intercepts of the regression lines are determined, and then used as input parameters to MCBR models. Within the errors (-+σ, regression line slopes correspond to a large inflow during the earlier stage of evolution and to low or moderate outflow during the subsequent stages. A possible inner halo - outer (metal-poor bulge connection is also briefly discussed. Quantitative results cannot be considered for applications to the inner Galactic halo, unless selection effects and disk contamination are removed from halo samples, and discrepancies between different oxygen abundance determination methods are explained.

  19. Geology and petrophysical characterization of the Ferron Sandstone for 3-D simulation of a fluvial-deltaic reservoir. Annual report, October 1, 1996--September 30, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Chidsey, T.C. Jr.; Anderson, P.B.; Morris, T.H.; Dewey, J.A. Jr.; Mattson, A.; Foster, C.B.; Snelgrove, S.H.; Ryer, T.A.

    1998-05-01

    The objective of the Ferron Sandstone (Utah) project is to develop a comprehensive, interdisciplinary, quantitative characterization of a fluvial-deltaic reservoir to allow realistic interwell and reservoir-scale models to be developed for improved oil-field development in similar reservoirs world-wide. Both new and existing data is being integrated into a 3-D model of spatial variations in porosity, storativity, and tensorial rock permeability at a scale appropriate for inter-well to regional-scale reservoir simulation. Simulation results could improve reservoir management through proper infill and extension drilling strategies, reduction of economic risks, increased recovery from existing oil fields, and more reliable reserve calculations. The project is divided into four tasks: (1) regional stratigraphic analysis, (2) case studies, (3) reservoirs models, and (4) field-scale evaluation of exploration strategies. The primary objective of the regional stratigraphic analysis is to provide a more detailed interpretation of the stratigraphy and gross reservoir characteristics of the Ferron Sandstone as exposed in outcrop. The primary objective of the case-studies work is to develop a detailed geological and petrophysical characterization, at well-sweep scale or smaller, of the primary reservoir lithofacies typically found in a fluvial-dominated deltaic reservoir. Work on tasks 3 and 4 consisted of developing two- and three-dimensional reservoir models at various scales. The bulk of the work on these tasks is being completed primarily during the last year of the project, and is incorporating the data and results of the regional stratigraphic analysis and case-studies tasks.

  20. Three-Dimensional Modeling of Fracture Clusters in Geothermal Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Ghassemi, Ahmad [Univ. of Oklahoma, Norman, OK (United States)

    2017-08-11

    The objective of this is to develop a 3-D numerical model for simulating mode I, II, and III (tensile, shear, and out-of-plane) propagation of multiple fractures and fracture clusters to accurately predict geothermal reservoir stimulation using the virtual multi-dimensional internal bond (VMIB). Effective development of enhanced geothermal systems can significantly benefit from improved modeling of hydraulic fracturing. In geothermal reservoirs, where the temperature can reach or exceed 350oC, thermal and poro-mechanical processes play an important role in fracture initiation and propagation. In this project hydraulic fracturing of hot subsurface rock mass will be numerically modeled by extending the virtual multiple internal bond theory and implementing it in a finite element code, WARP3D, a three-dimensional finite element code for solid mechanics. The new constitutive model along with the poro-thermoelastic computational algorithms will allow modeling the initiation and propagation of clusters of fractures, and extension of pre-existing fractures. The work will enable the industry to realistically model stimulation of geothermal reservoirs. The project addresses the Geothermal Technologies Office objective of accurately predicting geothermal reservoir stimulation (GTO technology priority item). The project goal will be attained by: (i) development of the VMIB method for application to 3D analysis of fracture clusters; (ii) development of poro- and thermoelastic material sub-routines for use in 3D finite element code WARP3D; (iii) implementation of VMIB and the new material routines in WARP3D to enable simulation of clusters of fractures while accounting for the effects of the pore pressure, thermal stress and inelastic deformation; (iv) simulation of 3D fracture propagation and coalescence and formation of clusters, and comparison with laboratory compression tests; and (v) application of the model to interpretation of injection experiments (planned by our

  1. Experiments with Interaction between the National Water Model and the Reservoir System Simulation Model: A Case Study of Russian River Basin

    Science.gov (United States)

    Kim, J.; Johnson, L.; Cifelli, R.; Chandra, C. V.; Gochis, D.; McCreight, J. L.; Yates, D. N.; Read, L.; Flowers, T.; Cosgrove, B.

    2017-12-01

    NOAA National Water Center (NWC) in partnership with the National Centers for Environmental Prediction (NCEP), the National Center for Atmospheric Research (NCAR) and other academic partners have produced operational hydrologic predictions for the nation using a new National Water Model (NWM) that is based on the community WRF-Hydro modeling system since the summer of 2016 (Gochis et al., 2015). The NWM produces a variety of hydrologic analysis and prediction products, including gridded fields of soil moisture, snowpack, shallow groundwater levels, inundated area depths, evapotranspiration as well as estimates of river flow and velocity for approximately 2.7 million river reaches. Also included in the NWM are representations for more than 1,200 reservoirs which are linked into the national channel network defined by the USGS NHDPlusv2.0 hydrography dataset. Despite the unprecedented spatial and temporal coverage of the NWM, many known deficiencies exist, including the representation of lakes and reservoirs. This study addresses the implementation of a reservoir assimilation scheme through coupling of a reservoir simulation model to represent the influence of managed flows. We examine the use of the reservoir operations to dynamically update lake/reservoir storage volume states, characterize flow characteristics of river reaches flowing into and out of lakes and reservoirs, and incorporate enhanced reservoir operating rules for the reservoir model options within the NWM. Model experiments focus on a pilot reservoir domain-Lake Mendocino, CA, and its contributing watershed, the East Fork Russian River. This reservoir is modeled using United States Army Corps of Engineers (USACE) HEC-ResSim developed for application to examine forecast informed reservoir operations (FIRO) in the Russian River basin.

  2. Calibration of Seismic Attributes for Reservoir Characterization; ANNUAL

    International Nuclear Information System (INIS)

    Pennington, Wayne D.; Acevedo, Horacio; Green, Aaron; Len, Shawn; Minavea, Anastasia; Wood, James; Xie, Deyi

    2002-01-01

    This project has completed the initially scheduled third year of the contract, and is beginning a fourth year, designed to expand upon the tech transfer aspects of the project. From the Stratton data set, demonstrated that an apparent correlation between attributes derived along 'phantom' horizons are artifacts of isopach changes; only if the interpreter understands that the interpretation is based on this correlation with bed thickening or thinning, can reliable interpretations of channel horizons and facies be made. From the Boonsville data set , developed techniques to use conventional seismic attributes, including seismic facies generated under various neural network procedures, to subdivide regional facies determined from logs into productive and non-productive subfacies, and developed a method involving cross-correlation of seismic waveforms to provide a reliable map of the various facies present in the area. The Teal South data set provided a surprising set of data, leading us to develop a pressure-dependent velocity relationship and to conclude that nearby reservoirs are undergoing a pressure drop in response to the production of the main reservoir, implying that oil is being lost through their spill points, never to be produced. The Wamsutter data set led to the use of unconventional attributes including lateral incoherence and horizon-dependent impedance variations to indicate regions of former sand bars and current high pressure, respectively, and to evaluation of various upscaling routines

  3. Daily reservoir inflow forecasting combining QPF into ANNs model

    Science.gov (United States)

    Zhang, Jun; Cheng, Chun-Tian; Liao, Sheng-Li; Wu, Xin-Yu; Shen, Jian-Jian

    2009-01-01

    Daily reservoir inflow predictions with lead-times of several days are essential to the operational planning and scheduling of hydroelectric power system. The demand for quantitative precipitation forecasting (QPF) is increasing in hydropower operation with the dramatic advances in the numerical weather prediction (NWP) models. This paper presents a simple and an effective algorithm for daily reservoir inflow predictions which solicits the observed precipitation, forecasted precipitation from QPF as predictors and discharges in following 1 to 6 days as predicted targets for multilayer perceptron artificial neural networks (MLP-ANNs) modeling. An improved error back-propagation algorithm with self-adaptive learning rate and self-adaptive momentum coefficient is used to make the supervised training procedure more efficient in both time saving and search optimization. Several commonly used error measures are employed to evaluate the performance of the proposed model and the results, compared with that of ARIMA model, show that the proposed model is capable of obtaining satisfactory forecasting not only in goodness of fit but also in generalization. Furthermore, the presented algorithm is integrated into a practical software system which has been severed for daily inflow predictions with lead-times varying from 1 to 6 days of more than twenty reservoirs operated by the Fujian Province Grid Company, China.

  4. Advanced reservoir characterization for improved oil recovery in a New Mexico Delaware basin project

    Energy Technology Data Exchange (ETDEWEB)

    Martin, F.D.; Kendall, R.P.; Whitney, E.M. [Dave Martin and Associates, Inc., Socorro, NM (United States)] [and others

    1997-08-01

    The Nash Draw Brushy Canyon Pool in Eddy County, New Mexico is a field demonstration site in the Department of Energy Class III program. The basic problem at the Nash Draw Pool is the low recovery typically observed in similar Delaware fields. By comparing a control area using standard infill drilling techniques to a pilot area developed using advanced reservoir characterization methods, the goal of the project is to demonstrate that advanced technology can significantly improve oil recovery. During the first year of the project, four new producing wells were drilled, serving as data acquisition wells. Vertical seismic profiles and a 3-D seismic survey were acquired to assist in interwell correlations and facies prediction. Limited surface access at the Nash Draw Pool, caused by proximity of underground potash mining and surface playa lakes, limits development with conventional drilling. Combinations of vertical and horizontal wells combined with selective completions are being evaluated to optimize production performance. Based on the production response of similar Delaware fields, pressure maintenance is a likely requirement at the Nash Draw Pool. A detailed reservoir model of pilot area was developed, and enhanced recovery options, including waterflooding, lean gas, and carbon dioxide injection, are being evaluated.

  5. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin), Class III

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, Shirley P.; Flanders, William A.

    2001-11-04

    The objective of this Class III project was demonstrate that reservoir characterization and enhanced oil recovery (EOR) by CO2 flood can increase production from slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico. Phase 1 of the project, reservoir characterization, focused on Geraldine Ford and East Ford fields, which are Delaware Mountain Group fields that produce from the upper Bell Canyon Formation (Ramsey sandstone). The demonstration phase of the project was a CO2 flood conducted in East Ford field, which is operated by Orla Petco, Inc., as the East Ford unit.

  6. Risk Decision Making Model for Reservoir Floodwater resources Utilization

    Science.gov (United States)

    Huang, X.

    2017-12-01

    Floodwater resources utilization(FRU) can alleviate the shortage of water resources, but there are risks. In order to safely and efficiently utilize the floodwater resources, it is necessary to study the risk of reservoir FRU. In this paper, the risk rate of exceeding the design flood water level and the risk rate of exceeding safety discharge are estimated. Based on the principle of the minimum risk and the maximum benefit of FRU, a multi-objective risk decision making model for FRU is constructed. Probability theory and mathematical statistics method is selected to calculate the risk rate; C-D production function method and emergy analysis method is selected to calculate the risk benefit; the risk loss is related to flood inundation area and unit area loss; the multi-objective decision making problem of the model is solved by the constraint method. Taking the Shilianghe reservoir in Jiangsu Province as an example, the optimal equilibrium solution of FRU of the Shilianghe reservoir is found by using the risk decision making model, and the validity and applicability of the model are verified.

  7. Application of Artificial Intelligence to Reservoir Characterization - An Interdisciplinary Approach

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, B.G.; Gamble, R.F.; Kerr, D.R.; Thompson, L.G.; Shenoi, S.

    2000-01-12

    The primary goal of this project is to develop a user-friendly computer program to integrate geological and engineering information using Artificial Intelligence (AI) methodology. The project is restricted to fluvially dominated deltaic environments. The static information used in constructing the reservoir description includes well core and log data. Using the well core and the log data, the program identifies the marker beds, and the type of sand facies, and in turn, develops correlation's between wells. Using the correlation's and sand facies, the program is able to generate multiple realizations of sand facies and petrophysical properties at interwell locations using geostatistical techniques. The generated petrophysical properties are used as input in the next step where the production data are honored. By adjusting the petrophysical properties, the match between the simulated and the observed production rates is obtained.

  8. Geological and petrophysical characterization of the Ferron Sandstone for 3-D simulation of a fluvial-deltaic reservoir. Technical progress report, January 1, 1995--March 31, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Allison, M.L.

    1995-05-02

    The objective of this project is to develop a comprehensive, interdisciplinary, and quantitative characterization of a fluvial-deltaic reservoir which will allow realistic inter-well and reservoir-scale modeling to be developed for improved oil-field development in similar reservoirs world-wide. The geological and petrophysical properties of the Cretaceous Ferron Sandstone in east-central Utah will be quantitatively determined. Both new and existing data will be integrated into a three-dimensional representation of spatial variations in porosity, storativity, and tensorial rock permeability at a scale appropriate for inter-well to regional-scale reservoir simulation. Results could improve reservoir management through proper infill and extension drilling strategies, reduction of economic risks, increased recovery from existing oil fields, and more reliable reserve calculations. Transfer of the project results to the petroleum industry is an integral component of the project.

  9. Petrofacies analysis - the petrophysical tool for geologic/engineering reservoir characterization

    Energy Technology Data Exchange (ETDEWEB)

    Watney, W.L.; Guy, W.J.; Gerlach, P.M. [Kansas Geological Survey, Lawrence, KS (United States)] [and others

    1997-08-01

    Petrofacies analysis is defined as the characterization and classification of pore types and fluid saturations as revealed by petrophysical measures of a reservoir. The word {open_quotes}petrofacies{close_quotes} makes an explicit link between petroleum engineers concerns with pore characteristics as arbiters of production performance, and the facies paradigm of geologists as a methodology for genetic understanding and prediction. In petrofacies analysis, the porosity and resistivity axes of the classical Pickett plot are used to map water saturation, bulk volume water, and estimated permeability, as well as capillary pressure information, where it is available. When data points are connected in order of depth within a reservoir, the characteristic patterns reflect reservoir rock character and its interplay with the hydrocarbon column. A third variable can be presented at each point on the crossplot by assigning a color scale that is based on other well logs, often gamma ray or photoelectric effect, or other derived variables. Contrasts between reservoir pore types and fluid saturations will be reflected in changing patterns on the crossplot and can help discriminate and characterize reservoir heterogeneity. Many hundreds of analyses of well logs facilitated by spreadsheet and object-oriented programming have provided the means to distinguish patterns typical of certain complex pore types for sandstones and carbonate reservoirs, occurrences of irreducible water saturation, and presence of transition zones. The result has been an improved means to evaluate potential production such as bypassed pay behind pipe and in old exploration holes, or to assess zonation and continuity of the reservoir. Petrofacies analysis is applied in this example to distinguishing flow units including discrimination of pore type as assessment of reservoir conformance and continuity. The analysis is facilitated through the use of color cross sections and cluster analysis.

  10. Scalable and Robust BDDC Preconditioners for Reservoir and Electromagnetics Modeling

    KAUST Repository

    Zampini, S.

    2015-09-13

    The purpose of the study is to show the effectiveness of recent algorithmic advances in Balancing Domain Decomposition by Constraints (BDDC) preconditioners for the solution of elliptic PDEs with highly heterogeneous coefficients, and discretized by means of the finite element method. Applications to large linear systems generated by div- and curl- conforming finite elements discretizations commonly arising in the contexts of modelling reservoirs and electromagnetics will be presented.

  11. Geostatistical modeling of a fluviodeltaic reservoir in the Huyapari Field, Hamaca area, in the Faja Petrolifera del Orinoco, Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    De Ascencao, Erika M.; Munckton, Toni; Digregorio, Ricardo [Petropiar (Venezuela)

    2011-07-01

    The Huyapari field, situated within the Faja Petrolifera del Orinoco (FPO) of Venezuela presents unique problems in terms of modeling. This field is spread over a wide area and is therefore subject to variable oil quality and complex fluvial facies architecture. Ameriven and PDVSA have been working on characterizing the ld's reservoirs in this field since 2000 and the aim of this paper is to present these efforts. Among others, a 3-D seismic survey completed in 1998 and a stratigraphic framework built from 149 vertical wells were used for reservoir characterization. Geostatistical techniques such as sequential Gaussian simulation with locally varying mean and cloud transform were also used. Results showed that these geostatistical methods accurately represented the architecture and properties of the reservoir and its fluid distribution. This paper showed that the application of numerous different techniques in the Hamasca area permitted reservoir complexity to be captured.

  12. A new approach to integrate seismic and production data in reservoir models

    Energy Technology Data Exchange (ETDEWEB)

    Ouenes, A.; Chawathe, A.; Weiss, W. [New Mexico Tech, Socorro, NM (United States)] [and others

    1997-08-01

    A great deal of effort is devoted to reducing the uncertainties in reservoir modeling. For example, seismic properties are used to improve the characterization of interwell properties by providing porosity maps constrained to seismic impedance. Another means to reduce uncertainties is to constrain the reservoir model to production data. This paper describes a new approach where the production and seismic data are simultaneously used to reduce the uncertainties. In this new approach, the primary geologic parameter that controls reservoir properties is identified. Next, the geophysical parameter that is sensitive to the dominant geologic parameter is determined. Then the geology and geophysics are linked using analytic correlations. Unfortunately, the initial guess resulted in a reservoir model that did not match the production history. Since the time required for trial and error matching of production history is exorbitant, an automatic history matching method based on a fast optimization method was used to find the correlating parameters. This new approach was illustrated with an actual field in the Williston Basin. Upscalling problems do not arise since the scale is imposed by the size of the seismic bin (66m, 219 ft) which is the size of the simulator gridblocks.

  13. Analysis of structural heterogeneities on drilled cores: a reservoir modeling oriented methodology; Analyse des heterogeneites structurales sur carottes: une methodologie axee vers la modelisation des reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Cortes, P.; Petit, J.P. [Montpellier-2 Univ., Lab. de Geophysique, Tectonique et Sedimentologie, UMR CNRS 5573, 34 (France); Guy, L. [ELF Aquitaine Production, 64 - Pau (France); Thiry-Bastien, Ph. [Lyon-1 Univ., 69 (France)

    1999-07-01

    The characterization of structural heterogeneities of reservoirs is of prime importance for hydrocarbons recovery. A methodology is presented which allows to compare the dynamic behaviour of fractured reservoirs and the observation of microstructures on drilled cores or surface reservoir analogues. (J.S.)

  14. Applications of resistivity modeling in reservoir development: examples from Balder Field, Norwegian North Sea

    Science.gov (United States)

    Paillet, Frederick L.; Haynes, F.M.; Buretz, O.M.

    2001-01-01

    The massive Paleocene oil sands of the Balder Field are overlain by several thinly bedded Eocene sand-prone packages of variable facies and reservoir quality. Although these sands have been penetrated by numerous exploration and development wells, uncertainty remains as to their extent, distribution, and ultimate effect on reservoir performance. The section is geologically complex (thin beds, injected sands, shale clasts and laminae, and faulting), and also contains a field-wide primary gas cap. With a depletion plan involving both gas and water injection, geologic/reservoir characterization of the Eocene is critical for prudent resource management during depletion. With this goal, resistivity modeling and core-based thin bed reservoir description from the first phase of development drilling have been integrated with seismic attribute mapping. Detailed core description, core permeability and grain size distribution data delineate six facies and help in distinguishing laterally continuous massive and laminated sands from potentially non-connected injection sands and non-reservoir quality siltstones and tuffs. Volumetric assessment of the thin sand resource has been enhanced by I-D forward modeling of induction log response using a commercial resistivity modeling program, R,BAN. After defining beds and facies with core and high resolution log data, the AHF60 array induction curve response was approximated using the 6FF40 response. Because many of the beds were thinner than 6FF40 resolution, the modeling is considered to provide a lower bound on R,. However, for most beds this model-based R, is significantly higher than that provided by one-foot vertical resolution shallow resistivity data, and is thought to be the best available estimate of true formation resistivity. Sensitivities in STOOIP were assessed with multiple R, earth models which can later be tested against production results. In addition, water saturation height functions, developed in vertical wells and

  15. Contribution to the tectonic characterization of fractured reservoirs, I: photo-elasticimetric modelling of the stress perturbations near faults and the associated fracture network: application to oil reserves, II mechanisms for the 3D joint organization in a natural reservoir analogue (flat-lying Devonian Old Red Sandstones of Caitness in North Scotland); Contribution a la caracterisation tectonique des reservoirs fractures, I: modelisation photoelecticimetrique des perturbations de contrainte au voisinage des failles et de la fracturation associee: application petroliere, II: mecanismes de developpement en 3D des diaclases dans un analogue de reservoir, le Devonien tabulaire du caithness (Ecosse)

    Energy Technology Data Exchange (ETDEWEB)

    Auzias, V.

    1995-10-27

    In order to understand joint network organisation in oil reservoirs, as a first step we have adapted to technique (the photo-elasticimetry) to study stress fields in 2D. This method allows to determine the principal stress trajectories near faults, as well as the associated joint network organisation. Natural joint networks perturbed near faults are modeled and the parameters that control stress perturbation are proposed. With the aim of extrapolating joint data from a well to the entire reservoir our modelling is based on both 3 D seismic data and local joint data. The second part of our research was dedicated to studying joint propagation mechanisms in a natural reservoir analogue (flat-lying Devonian Old Red Sandstones of Caitness in North Scotland). Several exposure observation at different scales and in 3D (horizontal and cliff sections) allow to reconstitute the fracturing geometry from centimeter to kilometer scale and to link these to the regional tectonic history. This study shows that it is possible to differentiate three types of joints major joints, `classic` joints and micro-joints, each with different vertical persistence. New concepts on the 3D joint organisation have been deduced from field quantitative data, which can be applied to reservoir fracture modeling. In particular the non-coexistence phenomenon in a single bed of two regional joint sets with close strikes. Some joint development mechanisms are discussed: interaction between joints and sedimentary interfaces, joint distribution near faults, origin of en echelon arrays associated with joints. (author) 142 refs.

  16. Microstructural characterization of reservoir rocks by X-ray microtomography

    International Nuclear Information System (INIS)

    Fernandes, Jaquiel Salvi; Appoloni, Carlos Roberto

    2007-01-01

    The evaluation of microstructural parameters from reservoir rocks is of great importance for petroleum industries. This work presents measurements of total porosity and pore size distribution of a sandstone sample from Tumblagooda geological formation, extracted from the Kalbari National Park in Australia. X-ray microtomography technique was used for determining porosity and pore size distribution. Other techniques, such as mercury intrusion porosimetry and Archimedes method have also been applied for those determinations but since they are regarded destructive techniques, samples cannot usually be used for further analyses. X-ray microtomography, besides allowing future analyses of a sample already evaluated, also provides tridimensional images of the sample. The experimental configuration included a SkysCan 1172 from CENPES-PETROBRAS, Rio de Janeiro, Brazil. The spatial resolution of this equipment is 2.9 μm. Images have been reconstructed using NRecon software and analysed with the IMAGO software developed by the Laboratory of Porous Materials and Thermophysical Properties of the Department of Mechanical Engineering / Federal University of Santa Catarina, Florianopolis, Brazil

  17. Hydrological, geochemical, and ecological characterization of Kesterson Reservoir

    Energy Technology Data Exchange (ETDEWEB)

    1990-06-01

    This report describes Kesterson Reservoir related research activities carried out under a cooperative program between Lawrence Berkeley Laboratory and the Division of Agriculture and Natural Resources at the University of California during FY89. The primary objectives of these investigations are: Predict the extent, probability of the occurrence, and selenium concentrations in surface water of temporary wetland habitat at Kesterson; assess rates and direction of migration of the drainage water plume that seeped into the aquifer under Kesterson; monitor and predict changes in quantity and speciation of selenium in surface soils and vadose zone pore-waters; and develop a comprehensive strategy through soil, water, and vegetation management to safely dissipate the high concentrations of selenium accumulated in Kesterson soils. This report provides an up-date on progress made in each of these areas. Chapter 2 describes results of recent investigations of water table fluctuations and plume migration. Chapter 3 describes results of ongoing monitoring of soil water selenium concentrations and evaporative accumulation of selenium at the soil surface. Chapter 4 describes early results from the soil, water, and vegetation management field trials as well as supporting laboratory and theoretical studies. In Chapter 5, new analytical methods for selenium speciation are described and quality assurance/quality control statistics for selenium and boron are provided. 110 refs., 138 figs., 62 tabs.

  18. Characterization of microbial community and the alkylscccinate synthase genes in petroleum reservoir fluids of China

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Lei; Mu, Bo-Zhong [University of Science and Technology (China)], email: bzmu@ecust.edu.cn; Gu, Ji-Dong [The University of Hong Kong (China)], email: jdgu@hkucc.hku.hk

    2011-07-01

    Petroleum reservoirs represent a special ecosystem consisting of specific temperature, pressure, salt concentration, oil, gas, water, microorganisms and, enzymes among others. This paper presents the characterization of microbial community and the alkyl succinate synthase genes in petroleum reservoir fluids in China. A few samples were analyzed and the physical and chemical characteristics are given in a tabular form. A flow chart shows the methods and procedures for microbial activities. Six petroleum reservoirs were studied using an archaeal 16S rRNA gene-based approach to establish the presence of archaea and the results are given. The correlation of archaeal and bacterial communities with reservoir conditions and diversity of the arachaeal community in water-flooding petroleum reservoirs at different temperatures is also shown. From the study, it can be summarized that, among methane producers, CO2-reducing methanogens are mostly found in oil reservoir ecosystems and as more assA sequences are revealed, more comprehensive molecular probes can be designed to track the activity of anaerobic alkane-degrading organisms in the environment.

  19. Model design for predicting extreme precipitation event impacts on water quality in a water supply reservoir

    Science.gov (United States)

    Hagemann, M.; Jeznach, L. C.; Park, M. H.; Tobiason, J. E.

    2016-12-01

    Extreme precipitation events such as tropical storms and hurricanes are by their nature rare, yet have disproportionate and adverse effects on surface water quality. In the context of drinking water reservoirs, common concerns of such events include increased erosion and sediment transport and influx of natural organic matter and nutrients. As part of an effort to model the effects of an extreme precipitation event on water quality at the reservoir intake of a major municipal water system, this study sought to estimate extreme-event watershed responses including streamflow and exports of nutrients and organic matter for use as inputs to a 2-D hydrodynamic and water quality reservoir model. Since extreme-event watershed exports are highly uncertain, we characterized and propagated predictive uncertainty using a quasi-Monte Carlo approach to generate reservoir model inputs. Three storm precipitation depths—corresponding to recurrence intervals of 5, 50, and 100 years—were converted to streamflow in each of 9 tributaries by volumetrically scaling 2 storm hydrographs from the historical record. Rating-curve models for concentratoin, calibrated using 10 years of data for each of 5 constituents, were then used to estimate the parameters of a multivariate lognormal probability model of constituent concentrations, conditional on each scenario's storm date and streamflow. A quasi-random Halton sequence (n = 100) was drawn from the conditional distribution for each event scenario, and used to generate input files to a calibrated CE-QUAL-W2 reservoir model. The resulting simulated concentrations at the reservoir's drinking water intake constitute a low-discrepancy sample from the estimated uncertainty space of extreme-event source water-quality. Limiting factors to the suitability of this approach include poorly constrained relationships between hydrology and constituent concentrations, a high-dimensional space from which to generate inputs, and relatively long run

  20. Modelling of Hydropower Reservoir Variables for Energy Generation ...

    African Journals Online (AJOL)

    Efficient management of hydropower reservoir can only be realized when there is sufficient understanding of interactions existing between reservoir variables and energy generation. Reservoir inflow, storage, reservoir elevation, turbine release, net generating had, plant use coefficient, tail race level and evaporation losses ...

  1. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2001-09-14

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 1 of the project has been reservoir description and characterization. This effort has included four tasks: (1) geoscientific reservoir characterization, (2) the study of rock-fluid interactions, (3) petrophysical and engineering characterization and (4) data integration. This work was scheduled for completion in Year 1. Overall, the project work is on schedule. Geoscientific reservoir characterization is essentially completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been initiated. Observations regarding the diagenetic processes influencing pore system development and heterogeneity in these reef and shoal reservoirs have been

  2. Application of artificial intelligence to reservoir characterization: An interdisciplinary approach. Annual report, October 1994--October 1995

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, D.; Thompson, L.; Shenoi, S.

    1996-01-01

    The basis of this research is to apply novel techniques from Artificial Intelligence and Expert Systems in capturing, integrating and articulating key knowledge from geology, geostatistics, and petroleum engineering to develop accurate descriptions of petroleum reservoirs. The ultimate goal is to design and implement a single powerful expert system for use by small producers and independents to efficiently exploit reservoirs. The main challenge of the proposed research is to automate the generation of detailed reservoir descriptions honoring all the available soft and hard data that ranges from qualitative and semi-quantitative geological interpretations to numeric data obtained from cores, well tests, well logs and production statistics. Additional challenges are the verification and validation of the expert system, since much of the interpretation of the experts is based on extended experience in reservoir characterization. The overall project plan to design the system to create integrated reservoir descriptions begins by initially developing an AI-based methodology for producing large-scale reservoir descriptions generated interactively from geology and well test data. Parallel to this task is a second task that develops an AI-based methodology that uses facies-biased information to generate small-scale descriptions of reservoir properties such as permeability and porosity. The third task involves consolidation and integration of the large-scale and small-scale methodologies to produce reservoir descriptions honoring all the available data. The final task will be technology transfer. With this plan, the authors have carefully allocated and sequenced the activities involved in each of the tasks to promote concurrent progress towards the research objectives. Moreover, the project duties are divided among the faculty member participants. Graduate students will work in terms with faculty members.

  3. Integrated Reflection Seismic Monitoring and Reservoir Modeling for Geologic CO2 Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    John Rogers

    2011-12-31

    The US DOE/NETL CCS MVA program funded a project with Fusion Petroleum Technologies Inc. (now SIGMA) to model the proof of concept of using sparse seismic data in the monitoring of CO{sub 2} injected into saline aquifers. The goal of the project was to develop and demonstrate an active source reflection seismic imaging strategy based on deployment of spatially sparse surface seismic arrays. The primary objective was to test the feasibility of sparse seismic array systems to monitor the CO{sub 2} plume migration injected into deep saline aquifers. The USDOE/RMOTC Teapot Dome (Wyoming) 3D seismic and reservoir data targeting the Crow Mountain formation was used as a realistic proxy to evaluate the feasibility of the proposed methodology. Though the RMOTC field has been well studied, the Crow Mountain as a saline aquifer has not been studied previously as a CO{sub 2} sequestration (storage) candidate reservoir. A full reprocessing of the seismic data from field tapes that included prestack time migration (PSTM) followed by prestack depth migration (PSDM) was performed. A baseline reservoir model was generated from the new imaging results that characterized the faults and horizon surfaces of the Crow Mountain reservoir. The 3D interpretation was integrated with the petrophysical data from available wells and incorporated into a geocellular model. The reservoir structure used in the geocellular model was developed using advanced inversion technologies including Fusion's ThinMAN{trademark} broadband spectral inversion. Seal failure risk was assessed using Fusion's proprietary GEOPRESS{trademark} pore pressure and fracture pressure prediction technology. CO{sub 2} injection was simulated into the Crow Mountain with a commercial reservoir simulator. Approximately 1.2MM tons of CO{sub 2} was simulated to be injected into the Crow Mountain reservoir over 30 years and subsequently let 'soak' in the reservoir for 970 years. The relatively small plume

  4. Characterization of facies and permeability patterns in carbonate reservoirs based on outcrop analogs. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kerans, C.; Lucia, F.J.; Senger, R.K.; Fogg, G.E.; Nance, H.S.; Hovorka, S.D.

    1993-07-01

    The primary objective of this research is to develop methods for better describing the three-dimensional geometry of carbonate reservoir flow units as related to conventional or enhanced recovery of oil. San Andres and Grayburg reservoirs were selected for study because of the 13 Bbbl of remaining mobile oil and 17 Bbbl of residual oil in these reservoirs. The key data base is provided by detailed characterization of geologic facies and rock permeability in reservior-scale outcrops of the Permian San Andres Formation in the Guadalupe Mountains of New Mexico. Emphasis is placed on developing an outcrop analog for San Andres strata that can be used as (1) a guide to interpreting the regional and local geologic framework of the subsurface reservoirs (2) a data source illustrating the scales and patterns of variability of rock-fabric facies and petrophysical properties, particularly in lateral dimension, and on scales that cannot be studied during subsurface reservoir characterization. The research approach taken to achieve these objectives utilizes the integration of geologic description, geostatistical techniques, and reservoir flow simulation experiments. Results from this research show that the spatial distribution of facies relative to the waterflood direction can significantly affect how the reservoir produces. Bypassing of unswept oil occurs due to cross flow of injected water from high permeability zones into lower permeability zones were high permeability zones terminate. An area of unswept oil develops because of the slower advance of the water-injection front in the lower permeability zones. When the injection pattern is reversed, the cross-flow effect changes due to the different arrangements of rock-fabric flow units relative to the flow of injected water, and the sweep efficiency is significantly different. Flow across low-permeability mudstones occurs showing that these layers do not necessarily represent flow barriers.

  5. Characterization of reservoir fractures using conventional geophysical logging

    Directory of Open Access Journals (Sweden)

    Paitoon Laongsakul

    2011-04-01

    Full Text Available In hydrocarbon exploration fractures play an important role as possible pathways for the hydrocarbon flow and bythis enhancing the overall formation’s permeability. Advanced logging methods for fracture analysis, like the boreholeacoustic televiewer and Formation Microscanner (FMS are available, but these are additional and expensive tools. However,open and with water or hydrocarbon filled fractures are also sensitive to electrical and other conventional logging methods.For this study conventional logging data (electric, seismic, etc were available plus additional fracture information from FMS.Taking into account the borehole environment the results show that the micro-spherically focused log indicates fractures byshowing low resistivity spikes opposite open fractures, and high resistivity spikes opposite sealed ones. Compressional andshear wave velocities are reduced when passing trough the fracture zone, which are assumed to be more or less perpendicularto borehole axis. The photoelectric absorption curve exhibit a very sharp peak in front of a fracture filled with bariteloaded mud cake. The density log shows low density spikes that are not seen by the neutron log, usually where fractures,large vugs, or caverns exist. Borehole breakouts can cause a similar effect on the logging response than fractures, but fracturesare often present when this occurs. The fracture index calculation by using threshold and input weight was calculatedand there was in general a good agreement with the fracture data from FMS especially in fracture zones, which mainlycontribute to the hydraulic system of the reservoir. Finally, the overall results from this study using one well are promising,however further research in the combination of different tools for fracture identification is recommended as well as the useof core for further validation.

  6. Ensemble-based reservoir characterization using time-lapse seismic waveform data

    NARCIS (Netherlands)

    Leeuwenburgh, O.; Brouwer, J.; Trani, M.

    2010-01-01

    Assisted history matching methods are beginning to offer the possibility to use 4D seismic data in quantitative ways for reservoir characterization. We use the waveform data without any explicit inversion or interpretation step directly in an ensemble-based assisted history matching scheme with a 3D

  7. Optimal model of radiocarbon residence time in exchange reservoir

    International Nuclear Information System (INIS)

    Dergachev, V.A.

    1977-01-01

    Radiocarbon content variations in the earth atmosphere were studied using a mathematical model. The so-called exchange reservoir was considered consisting of layers, and the radiocarbon exchange rate at the interfaces between these layers was supposed to be constant. The process of 14 C mixing and exchange in a dynamic system is described by a system of nonhomogeneous 1st order differential equations. The model also accounts for the change in rate of radiocarbon formation in the earth atmosphere due to cosmic and geophysical effects (solar activity, solar cycle, etc.). (J.P.)

  8. Modelling sediment export, retention and reservoir sedimentation in drylands with the WASA-SED model

    Directory of Open Access Journals (Sweden)

    E. N. Mueller

    2010-04-01

    Full Text Available Current soil erosion and reservoir sedimentation modelling at the meso-scale is still faced with intrinsic problems with regard to open scaling questions, data demand, computational efficiency and deficient implementations of retention and re-mobilisation processes for the river and reservoir networks. To overcome some limitations of current modelling approaches, the semi-process-based, spatially semi-distributed modelling framework WASA-SED (Vers. 1 was developed for water and sediment transport in large dryland catchments. The WASA-SED model simulates the runoff and erosion processes at the hillslope scale, the transport and retention processes of suspended and bedload fluxes in the river reaches and the retention and remobilisation processes of sediments in reservoirs. The modelling tool enables the evaluation of management options both for sustainable land-use change scenarios to reduce erosion in the headwater catchments as well as adequate reservoir management options to lessen sedimentation in large reservoirs and reservoir networks. The model concept, its spatial discretisation scheme and the numerical components of the hillslope, river and reservoir processes are described and a model application for the meso-scale dryland catchment Isábena in the Spanish Pre-Pyrenees (445 km2 is presented to demonstrate the capabilities, strengths and limits of the model framework. The example application showed that the model was able to reproduce runoff and sediment transport dynamics of highly erodible headwater badlands, the transient storage of sediments in the dryland river system, the bed elevation changes of the 93 hm3 Barasona reservoir due to sedimentation as well as the life expectancy of the reservoir under different management options.

  9. 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

  10. On the effects of adaptive reservoir operating rules in hydrological physically-based models

    Science.gov (United States)

    Giudici, Federico; Anghileri, Daniela; Castelletti, Andrea; Burlando, Paolo

    2017-04-01

    Recent years have seen a significant increase of the human influence on the natural systems both at the global and local scale. Accurately modeling the human component and its interaction with the natural environment is key to characterize the real system dynamics and anticipate future potential changes to the hydrological regimes. Modern distributed, physically-based hydrological models are able to describe hydrological processes with high level of detail and high spatiotemporal resolution. Yet, they lack in sophistication for the behavior component and human decisions are usually described by very simplistic rules, which might underperform in reproducing the catchment dynamics. In the case of water reservoir operators, these simplistic rules usually consist of target-level rule curves, which represent the average historical level trajectory. Whilst these rules can reasonably reproduce the average seasonal water volume shifts due to the reservoirs' operation, they cannot properly represent peculiar conditions, which influence the actual reservoirs' operation, e.g., variations in energy price or water demand, dry or wet meteorological conditions. Moreover, target-level rule curves are not suitable to explore the water system response to climate and socio economic changing contexts, because they assume a business-as-usual operation. In this work, we quantitatively assess how the inclusion of adaptive reservoirs' operating rules into physically-based hydrological models contribute to the proper representation of the hydrological regime at the catchment scale. In particular, we contrast target-level rule curves and detailed optimization-based behavioral models. We, first, perform the comparison on past observational records, showing that target-level rule curves underperform in representing the hydrological regime over multiple time scales (e.g., weekly, seasonal, inter-annual). Then, we compare how future hydrological changes are affected by the two modeling

  11. THMC Modeling of EGS Reservoirs -- Continuum through Discontinuum Representations. Capturing Reservoir Stimulation, Evolution and Induced Seismicity

    Energy Technology Data Exchange (ETDEWEB)

    Elsworth, Derek [Pennsylvania State Univ., State College, PA (United States); Izadi, Ghazal [Pennsylvania State Univ., State College, PA (United States); Gan, Quan [Pennsylvania State Univ., State College, PA (United States); Fang, Yi [Pennsylvania State Univ., State College, PA (United States); Taron, Josh [US Geological Survey, Menlo Park, CA (United States); Sonnenthal, Eric [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-07-28

    This work has investigated the roles of effective stress induced by changes in fluid pressure, temperature and chemistry in contributing to the evolution of permeability and induced seismicity in geothermal reservoirs. This work has developed continuum models [1] to represent the progress or seismicity during both stimulation [2] and production [3]. These methods have been used to resolve anomalous observations of induced seismicity at the Newberry Volcano demonstration project [4] through the application of modeling and experimentation. Later work then focuses on the occurrence of late stage seismicity induced by thermal stresses [5] including the codifying of the timing and severity of such responses [6]. Furthermore, mechanistic linkages between observed seismicity and the evolution of permeability have been developed using data from the Newberry project [7] and benchmarked against field injection experiments. Finally, discontinuum models [8] incorporating the roles of discrete fracture networks have been applied to represent stimulation and then thermal recovery for new arrangements of geothermal wells incorporating the development of flow manifolds [9] in order to increase thermal output and longevity in EGS systems.

  12. Time-lapse seismic waveform modelling and attribute analysis using hydromechanical models for a deep reservoir undergoing depletion

    Science.gov (United States)

    He, Y.-X.; Angus, D. A.; Blanchard, T. D.; Wang, G.-L.; Yuan, S.-Y.; Garcia, A.

    2016-04-01

    Extraction of fluids from subsurface reservoirs induces changes in pore pressure, leading not only to geomechanical changes, but also perturbations in seismic velocities and hence observable seismic attributes. Time-lapse seismic analysis can be used to estimate changes in subsurface hydromechanical properties and thus act as a monitoring tool for geological reservoirs. The ability to observe and quantify changes in fluid, stress and strain using seismic techniques has important implications for monitoring risk not only for petroleum applications but also for geological storage of CO2 and nuclear waste scenarios. In this paper, we integrate hydromechanical simulation results with rock physics models and full-waveform seismic modelling to assess time-lapse seismic attribute resolution for dynamic reservoir characterization and hydromechanical model calibration. The time-lapse seismic simulations use a dynamic elastic reservoir model based on a North Sea deep reservoir undergoing large pressure changes. The time-lapse seismic traveltime shifts and time strains calculated from the modelled and processed synthetic data sets (i.e. pre-stack and post-stack data) are in a reasonable agreement with the true earth models, indicating the feasibility of using 1-D strain rock physics transform and time-lapse seismic processing methodology. Estimated vertical traveltime shifts for the overburden and the majority of the reservoir are within ±1 ms of the true earth model values, indicating that the time-lapse technique is sufficiently accurate for predicting overburden velocity changes and hence geomechanical effects. Characterization of deeper structure below the overburden becomes less accurate, where more advanced time-lapse seismic processing and migration is needed to handle the complex geometry and strong lateral induced velocity changes. Nevertheless, both migrated full-offset pre-stack and near-offset post-stack data image the general features of both the overburden and

  13. Pilon field : characterization of heavy crude oil reservoir with gas cap

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, J.; Rodriguez, R.; Urdaneta, R.; Sanchez, J. [PDVSA Petroleos de Venezuela SA, Caracas (Venezuela, Bolivarian Republic of); Bague, O. [Beicip-Franlab, Rueil-Malmaison (France)

    2009-07-01

    The Pilon mature oilfield covers a surface area of 100 square kilometres in the region of the Orinoco oil belt in eastern Venezuela. A study was undertaken regarding 3 reservoirs, of which 2 show a gas cap, contrary to previous studies which established that only 1 reservoir had a gas cap. This paper presented a 3D structural model that was created by defining fault planes and stratigraphic horizons. Stratigraphy, sedimentology, petrophysics, and geostatistics were also discussed. The geostatistic model was developed using the following techniques: facies simulation bias; rock type modeling; and petrophysical inputs. Production analysis and reservoir pressure analysis were also presented. Fluids distribution was discussed in terms of oil water contact and gas oil contact. Material balance was also addressed in the paper. It was concluded that the stratigraphic model underlines the existence of 6 distinct geological units spanning the whole field. 5 refs., 5 tabs., 27 figs.

  14. Reconstruction of rocks petrophysical properties as input data for reservoir modeling

    Science.gov (United States)

    Cantucci, B.; Montegrossi, G.; Lucci, F.; Quattrocchi, F.

    2016-11-01

    The worldwide increasing energy demand triggered studies focused on defining the underground energy potential even in areas previously discharged or neglected. Nowadays, geological gas storage (CO2 and/or CH4) and geothermal energy are considered strategic for low-carbon energy development. A widespread and safe application of these technologies needs an accurate characterization of the underground, in terms of geology, hydrogeology, geochemistry, and geomechanics. However, during prefeasibility study-stage, the limited number of available direct measurements of reservoirs, and the high costs of reopening closed deep wells must be taken into account. The aim of this work is to overcome these limits, proposing a new methodology to reconstruct vertical profiles, from surface to reservoir base, of: (i) thermal capacity, (ii) thermal conductivity, (iii) porosity, and (iv) permeability, through integration of well-log information, petrographic observations on inland outcropping samples, and flow and heat transport modeling. As case study to test our procedure we selected a deep structure, located in the medium Tyrrhenian Sea (Italy). Obtained results are consistent with measured data, confirming the validity of the proposed model. Notwithstanding intrinsic limitations due to manual calibration of the model with measured data, this methodology represents an useful tool for reservoir and geochemical modelers that need to define petrophysical input data for underground modeling before the well reopening.

  15. Simulating migrated and inverted seismic data for enhanced reservoir characterization

    NARCIS (Netherlands)

    Toxopeus, G.

    2006-01-01

    An optimal use of shared-earth modeling is hampered by the fact that simulating a migrated image that can be compared directly to the real migrated image is time-consuming. The key to enable iterative testing of different geological scenarios is to filter a shared-earth model by a spatial resolution

  16. 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

  17. Towards an integrated workflow for structural reservoir model updating and history matching

    NARCIS (Netherlands)

    Leeuwenburgh, O.; Peters, E.; Wilschut, F.

    2011-01-01

    A history matching workflow, as typically used for updating of petrophysical reservoir model properties, is modified to include structural parameters including the top reservoir and several fault properties: position, slope, throw and transmissibility. A simple 2D synthetic oil reservoir produced by

  18. AN INTEGRATED APPROACH TO CHARACTERIZING BYPASSED OIL IN HETEROGENEOUS AND FRACTURED RESERVOIRS USING PARTITIONING TRACERS

    Energy Technology Data Exchange (ETDEWEB)

    Akhil Datta-Gupta

    2003-08-01

    We explore the use of efficient streamline-based simulation approaches for modeling partitioning interwell tracer tests in hydrocarbon reservoirs. Specifically, we utilize the unique features of streamline models to develop an efficient approach for interpretation and history matching of field tracer response. A critical aspect here is the underdetermined and highly ill-posed nature of the associated inverse problems. We have adopted an integrated approach whereby we combine data from multiple sources to minimize the uncertainty and non-uniqueness in the interpreted results. For partitioning interwell tracer tests, these are primarily the distribution of reservoir permeability and oil saturation distribution. A novel approach to multiscale data integration using Markov Random Fields (MRF) has been developed to integrate static data sources from the reservoir such as core, well log and 3-D seismic data. We have also explored the use of a finite difference reservoir simulator, UTCHEM, for field-scale design and optimization of partitioning interwell tracer tests. The finite-difference model allows us to include detailed physics associated with reactive tracer transport, particularly those related with transverse and cross-streamline mechanisms. We have investigated the potential use of downhole tracer samplers and also the use of natural tracers for the design of partitioning tracer tests. Finally, the behavior of partitioning tracer tests in fractured reservoirs is investigated using a dual-porosity finite-difference model.

  19. Wellbore Microannulus Characterization and Modeling.

    Energy Technology Data Exchange (ETDEWEB)

    Matteo, Edward N; Sobolik, Steven R.; Stormont, John C.; Taha, Mahmoud Reda; Gomez, Steven Paul

    2016-05-01

    Subsurface geologic formations used for extracting resources such as oil and gas can subsequently be used as a storage reservoir for the common greenhouse gas CO2, a concept known as Carbon Capture and Storage (CCS). Pre-existing wellbores penetrate the reservoirs where supercritical CO2 is to be injected. These wellbores can potentially be a pathway for contamination if CO2 leaks through wellbore flaws to an overlying aquifer or the atmosphere. Characterizing wellbore integrity and providing zonal isolation by repairing these wellbore flaws is of critical importance to the long-term isolation of CO2 and success of CCS. This research aims to characterize the microannulus region of the cement sheath-steel casing interface in terms of its compressibility and permeability. A mock-up of a wellbore system was used for lab-scale testing. Specimens, consisting of a cement sheath cast on a steel casing with microannuli, were subjected to confining pressures and casing pressures in a pressure vessel that allows simultaneous measurement of gas flow along the axis of the specimen. The flow was interpreted as the hydraulic aperture of the microannuli. Numerical models are used to analyze stress and displacement conditions along the casing-cement interface. These numerical results provide good agreement with closed-form elastic solutions. Numerical models incorporating flaws of varying dimensions along the casing-cement interface were then developed to describe the microannulus region. A joint model is used to describe the hydraulic aperture of the microannulus region, whose mechanical stiffness is altered in response to the imposed stress state across the joint interface. The aperture-stress behavior is based upon laboratory measurements of hydraulic aperture as a function of imposed stress conditions. This investigation found that microannulus permeability can satisfactorily be described by a joint model and that the constitutive

  20. An analytical thermohydraulic model for discretely fractured geothermal reservoirs

    Science.gov (United States)

    Fox, Don B.; Koch, Donald L.; Tester, Jefferson W.

    2016-09-01

    In discretely fractured reservoirs such as those found in Enhanced/Engineered Geothermal Systems (EGS), knowledge of the fracture network is important in understanding the thermal hydraulics, i.e., how the fluid flows and the resulting temporal evolution of the subsurface temperature. The purpose of this study was to develop an analytical model of the fluid flow and heat transport in a discretely fractured network that can be used for a wide range of modeling applications and serve as an alternative analysis tool to more computationally intensive numerical codes. Given the connectivity and structure of a fracture network, the flow in the system was solved using a linear system of algebraic equations for the pressure at the nodes of the network. With the flow determined, the temperature in the fracture was solved by coupling convective heat transport in the fracture with one-dimensional heat conduction perpendicular to the fracture, employing the Green's function derived solution for a single discrete fracture. The predicted temperatures along the fracture surfaces from the analytical solution were compared to numerical simulations using the TOUGH2 reservoir code. Through two case studies, we showed the capabilities of the analytical model and explored the effect of uncertainty in the fracture apertures and network structure on thermal performance. While both sources of uncertainty independently produce large variations in production temperature, uncertainty in the network structure, whenever present, had a predominant influence on thermal performance.

  1. Dispersion measurement as a method of quantifying geologic characterization and defining reservoir heterogeneity. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Menzie, D.E.

    1995-05-01

    The main objective of this research project is to investigate dispersion as a method of quantifying geological characterization and defining reservoir heterogeneity in order to enhance crude oil recovery. The dispersion of flow of a reservoir rock (dispersion coefficient and dispersivity) was identified as one of the physical properties of a reservoir rock by measuring the mixing of two miscible fluids, one displacing the other in a porous medium. A rock was 100% saturated with a resident fluid and displaced by a miscible fluid of equal viscosity and equal density. Some specific experiments were performed with unequal densities. Produced fluid was analyzed by refractometer, nuclear reaction, electrical conductivity and X-ray scan. Several physical and flow characteristics were measured on the sand rock sample in order to establish correlations with the measured dispersion property. Absolute permeability, effective porosity, relative permeability, capillary pressure, the heterogeneity factor and electrical conductivity were used to better understand the flow system. Linear, transverse, 2-D and 3-D dispersions were measured and used to characterize the rock heterogeneity of the flow system. A new system of measuring dispersion was developed using a gas displacing gas system in a porous medium. An attempt was also made to determine the dispersion property of an actual reservoir from present day well log data on a producing well. 275 refs., 102 figs., 17 tabs.

  2. Class III Mid-Term Project, "Increasing Heavy Oil Reserves in the Wilmington Oil Field Through Advanced Reservoir Characterization and Thermal Production Technologies"

    Energy Technology Data Exchange (ETDEWEB)

    Scott Hara

    2007-03-31

    The overall objective of this project was to increase heavy oil reserves in slope and basin clastic (SBC) reservoirs through the application of advanced reservoir characterization and thermal production technologies. The project involved improving thermal recovery techniques in the Tar Zone of Fault Blocks II-A and V (Tar II-A and Tar V) of the Wilmington Field in Los Angeles County, near Long Beach, California. A primary objective has been to transfer technology that can be applied in other heavy oil formations of the Wilmington Field and other SBC reservoirs, including those under waterflood. The first budget period addressed several producibility problems in the Tar II-A and Tar V thermal recovery operations that are common in SBC reservoirs. A few of the advanced technologies developed include a three-dimensional (3-D) deterministic geologic model, a 3-D deterministic thermal reservoir simulation model to aid in reservoir management and subsequent post-steamflood development work, and a detailed study on the geochemical interactions between the steam and the formation rocks and fluids. State of the art operational work included drilling and performing a pilot steam injection and production project via four new horizontal wells (2 producers and 2 injectors), implementing a hot water alternating steam (WAS) drive pilot in the existing steamflood area to improve thermal efficiency, installing a 2400-foot insulated, subsurface harbor channel crossing to supply steam to an island location, testing a novel alkaline steam completion technique to control well sanding problems, and starting on an advanced reservoir management system through computer-aided access to production and geologic data to integrate reservoir characterization, engineering, monitoring, and evaluation. The second budget period phase (BP2) continued to implement state-of-the-art operational work to optimize thermal recovery processes, improve well drilling and completion practices, and evaluate the

  3. Advanced Reservoir Characterization and Evaluation of C02 Gravity Drainage in the Naturally Fractured Sprayberry Trend Area

    Energy Technology Data Exchange (ETDEWEB)

    David S. Schechter

    1998-04-30

    The objective is to assess the economic feasibility of CO2 flooding of the naturally fractured Straberry Trend Area in west Texas. Research is being conducted in the extensive characterization of the reservoirs, the experimental studies of crude oil/brine/rock (COBR) interaction in the reservoirs, the analytical and numerical simulation of Spraberry reservoirs, and the experimental investigations on CO2 gravity drainage in Spraberry whole cores.

  4. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin)

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, S.P.; Flanders, W.A.; Guzman, J.I.; Zirczy, H.

    1999-06-08

    The objective of this Class III project is to demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost-effective way to recover a higher percentage of the original oil in place through geologically based field development. This year the project focused on reservoir characterization of the East Ford unit, a representative Delaware Mountain Group field that produces from the upper Bell Canyon Formation (Ramsey Sandstone). The field, discovered in 1960, is operated by Orla Petco, Inc., as the East Ford unit; it contained an estimated 19.8 million barrels (MMbbl) of original oil in place. Petrophysical characterization of the East Ford unit was accomplished by integrating core and log data and quantifying petrophysical properties from wireline logs. Most methods of petrophysical analysis that had been developed during an earlier study of the Ford Geraldine unit were successfully transferred to the East Ford unit. The approach that was used to interpret water saturation from resistivity logs, however, had to be modified because in some East Ford wells the log-calculated water saturation was too high and inconsistent with observations made during the actual production. Log-porosity to core-porosity transforms and core-porosity to core-permeability transforms were derived from the East Ford reservoir. The petrophysical data were used to map porosity, permeability, net pay, water saturation, mobil-oil saturation, and other reservoir properties.

  5. APPLICATION OF RESERVOIR CHARACTERIZATION AND ADVANCED TECHNOLOGY TO IMPROVE RECOVERY AND ECONOMICS IN A LOWER QUALITY SHALLOW SHELF SAN ANDRES RESERVOIR

    Energy Technology Data Exchange (ETDEWEB)

    Tom Beebe

    2003-05-05

    The OXY-operated Class 2 Project at West Welch is designed to demonstrate how the use of advanced technology can improve the economics of miscible CO{sub 2} injection projects in lower quality Shallow Shelf Carbonate reservoirs. The research and design phase (Budget Period 1) primarily involved advanced reservoir characterization. The current demonstration phase (Budget Period 2) is the implementation of the reservoir management plan for an optimum miscible CO{sub 2} flood design based on the reservoir characterization. Although Budget Period 1 for the Project officially ended 12/31/96, reservoir characterization and simulation work continued during the Budget Period 2. During the seventh annual reporting period (8/3/00-8/2/01) covered by this report, work continued on interpretation of the interwell seismic data to create porosity and permeability profiles which were distributed into the reservoir geostatistically. The initial interwell seismic CO{sub 2} monitor survey was conducted and the acquired data processed and interpretation started. Only limited well work and facility construction were conducted in the project area. The CO{sub 2} injection initiated in October 1997 was continued, although the operator had to modify the operating plan in response to low injection rates, well performance and changes in CO{sub 2} supply. CO{sub 2} injection was focused in a smaller area to increase the reservoir processing rate. By the end of the reporting period three producers had shown sustained oil rate increases and six wells had experienced gas (CO{sub 2}) breakthrough.

  6. Investigation of seasonal thermal flow in a real dam reservoir using 3-D numerical modeling

    Directory of Open Access Journals (Sweden)

    Üneş Fatih

    2015-03-01

    Full Text Available Investigations indicate that correct estimation of seasonal thermal stratification in a dam reservoir is very important for the dam reservoir water quality modeling and water management problems. The main aim of this study is to develop a hydrodynamics model of an actual dam reservoir in three dimensions for simulating a real dam reservoir flows for different seasons. The model is developed using nonlinear and unsteady continuity, momentum, energy and k-ε turbulence model equations. In order to include the Coriolis force effect on the flow in a dam reservoir, Coriolis force parameter is also added the model equations. Those equations are constructed using actual dimensions, shape, boundary and initial conditions of the dam and reservoir. Temperature profiles and flow visualizations are used to evaluate flow conditions in the reservoir. Reservoir flow’s process and parameters are determined all over the reservoir. The mathematical model developed is capable of simulating the flow and thermal characteristics of the reservoir system for seasonal heat exchanges. Model simulations results obtained are compared with field measurements obtained from gauging stations for flows in different seasons. The results show a good agreement with the field measurements.

  7. Characterization of fractures in a carbonate reservoir using walkaway VSP reverse time migration

    Science.gov (United States)

    Takam Takougang, E. M.; Bouzidi, Y.

    2017-12-01

    We present a case study of fracture characterization in a carbonate reservoir from an Abu Dhabi oil field, using reverse time migration of walkaway VSP data. The data were acquired offshore, in a deviated borehole, with an angle of deviation varying between 0 and 24 degree from the vertical direction. The line had a total length of 9 km with the receivers in the borehole located half-way down. Reverse time migration of the up-going wavefield was used to form a high resolution seismic image for interpretation. The reverse time migration scheme was based on a high-order finite-difference solution to the two-way acoustic wave equation. The seismic depth images of the subsurface were formed by the correlation of the forward propagation and the backward propagation of the acoustic wavefields. The velocity model for reverse time migration was derived by full waveform tomography, using the frequencies 4 to 50 Hz. Fractures were extracted from the seismic image using a workflow based on advance seismic attributes (deep steered attribute, similarity attribute) and the Hough's transform. After filtering the data to minimize any frequency related noise, dip-steered sections that contain seismic dips were computed. Similarity attribute were obtained using the previously computed deep steered attribute, and enabled us to extract features such as subtle faults and fractures. The Hough transform was then used to characterize the linear features (fractures and faults) from the similarity attribute. Based on the rose diagram of the orientation of fractures, it appears that the azimuth of the most characteristic strike direction is approximately 5 degree i.e. roughly north-south while that of the second most characteristic strike direction is approximately 20 degree. A few lines are strongly separated from the previous strike directions and are characterize with an azimuth of approximately 95 degree i.e. almost perpendicular. This implies that the development of fractures in the

  8. Characterization of cyanophyte biomass in a Bureau of Reclamation reservoir

    Science.gov (United States)

    Simon, Nancy S.; Ali, Ahmad Abdul; Samperton, Kyle Michael; Korson, Charles S.; Fischer, Kris; Hughes, Michael L.

    2013-01-01

    The purpose of this study was to characterize the cyanophyte Aphanizomenon flos-aquae (AFA) from Upper Klamath Lake, Oregon, (UKL) and, based on this description, explore uses for AFA, which would have commercial value. AFA collected from UKL in 2010 from eight sites during a period of approximately 2 weeks were similar in composition spatially and temporally. 31P nuclear magnetic resonance analysis of the samples indicated that the AFA samples contained a broad range of phosphorus-containing compounds. The largest variation in organic phosphorus compounds was found in a sample collected from Howard Bay compared with samples collected the sites at Pelican Marina, North Buck Island, Eagle Ridge, Eagle Ridge South, Shoalwater Bay, and Agency Lake South. 31P Nuclear Magnetic Resonance data indicated that the average ratio of inorganic phosphorus (orthophosphate) to organic phosphorus in the AFA samples was approximately 60:40 in extraction solutions of either water or a more rigorous solution of sodium hydroxide plus ethylenediaminetetraacetic acid. This indicates that when AFA cells senesce, die and lyse, cell contents added to the water column contain a broad spectrum of phosphorus-containing compounds approximately 50 percent of which are organic phosphorus compounds. The organic phosphorus content of AFA is directly and significantly related to the total carbon content of AFA. Total concentrations of the elements Al, Ca, Fe, Mg, Ti and Zn were similar in all samples with the exception of elevated iron in the July 27, 2010, sample from Pelican Marina. Iron concentration in the July 27, 2010, Pelican Marina sample was elevated; the concentration of iron in the August 9, 2010, sample from Pelican Marina was indistinguishable from iron in the other AFA samples that were collected. The carbon to nitrogen ratio in all AFA samples that were analyzed was 5.4 plus or minus 0.04 as compared with the Redfield ratio of carbon to nitrogen ratio of 6.6, which could be

  9. Characterization of Suspended-Sediment Loading to and from John Redmond Reservoir, East-Central Kansas, 2007-2008

    Science.gov (United States)

    Lee, Casey J.; Rasmussen, Patrick P.; Ziegler, Andrew C.

    2008-01-01

    Storage capacity in John Redmond Reservoir is being lost to sedimentation more rapidly than in other federal impoundments in Kansas. The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, initiated a study to characterize suspended-sediment loading to and from John Redmond Reservoir from February 21, 2007, through February 21, 2008. Turbidity sensors were installed at two U.S. Geological Survey stream gages upstream (Neosho River near Americus and the Cottonwood River near Plymouth) and one stream gage downstream (Neosho River at Burlington) from the reservoir to compute continuous, real-time (15-minute) measurements of suspended-sediment concentration and loading. About 1,120,000 tons of suspended-sediment were transported to, and 100,700 tons were transported from John Redmond Reservoir during the study period. Dependent on the bulk density of sediment stored in the reservoir, 5.0 to 1.4 percent of the storage in the John Redmond conservation pool was lost during the study period, with an average deposition of 3.4 to 1.0 inches. Nearly all (98-99 percent) of the incoming sediment load was transported during 9 storms which occurred 25 to 27 percent of the time. The largest storm during the study period (peak-flow recurrence interval of about 4.6-4.9 years) transported about 37 percent of the sediment load to the reservoir. Suspended-sediment yield from the unregulated drainage area upstream from the Neosho River near Americus was 530 tons per square mile, compared to 400 tons per square mile upstream from the Cottonwood River near Plymouth. Comparison of historical (1964-78) to current (2007) sediment loading estimates indicate statistically insignificant (99 percent) decrease in sediment loading at the Neosho River at Burlington. Ninety-percent confidence intervals of streamflow-derived estimates of total sediment load were 7 to 21 times larger than turbidity-derived estimates. Results from this study can be used by natural resource

  10. Out of the Reservoir: Phenotypic and Genotypic Characterization of a Novel Cowpox Virus Isolated from a Common Vole.

    Science.gov (United States)

    Hoffmann, Donata; Franke, Annika; Jenckel, Maria; Tamošiūnaitė, Aistė; Schluckebier, Julia; Granzow, Harald; Hoffmann, Bernd; Fischer, Stefan; Ulrich, Rainer G; Höper, Dirk; Goller, Katja; Osterrieder, Nikolaus; Beer, Martin

    2015-11-01

    The incidence of human cowpox virus (CPXV) infections has increased significantly in recent years. Serological surveys have suggested wild rodents as the main CPXV reservoir. We characterized a CPXV isolated during a large-scale screening from a feral common vole. A comparison of the full-length DNA sequence of this CPXV strain with a highly virulent pet rat CPXV isolate showed a sequence identity of 96%, including a large additional open reading frame (ORF) of about 6,000 nucleotides which is absent in the reference CPXV strain Brighton Red. Electron microscopy analysis demonstrated that the vole isolate, in contrast to the rat strain, forms A-type inclusion (ATI) bodies with incorporated virions, consistent with the presence of complete ati and p4c genes. Experimental infections showed that the vole CPXV strain caused only mild clinical symptoms in its natural host, while all rats developed severe respiratory symptoms followed by a systemic rash. In contrast, common voles infected with a high dose of the rat CPXV showed severe signs of respiratory disease but no skin lesions, whereas infection with a low dose led to virus excretion with only mild clinical signs. We concluded that the common vole is susceptible to infection with different CPXV strains. The spectrum ranges from well-adapted viruses causing limited clinical symptoms to highly virulent strains causing severe respiratory symptoms. In addition, the low pathogenicity of the vole isolate in its eponymous host suggests a role of common voles as a major CPXV reservoir, and future research will focus on the correlation between viral genotype and phenotype/pathotype in accidental and reservoir species. We report on the first detection and isolation of CPXV from a putative reservoir host, which enables comparative analyses to understand the infection cycle of these zoonotic orthopox viruses and the relevant genes involved. In vitro studies, including whole-genome sequencing as well as in vivo experiments

  11. Challenges of reservoir properties and production history matching in a CHOPS reservoir study

    Energy Technology Data Exchange (ETDEWEB)

    Alam, Mahbub [Department of Geoscience, University of Calgary (Canada)

    2011-07-01

    In order to meet increasing world energy demand, wells have to be drilled within very thin reservoir beds. This paper, we present one of the solutions for optimizing the reservoir characterization. Reservoir characterization is the process between the discovery of a property and the reservoir management phase. Principal data for reservoir modeling are: 4D Seismic interpretation, wireline log interpretation, core analysis, and petrophysical analysis. Reservoir conditions, perforation and completion technology are the key issues to the production rate of cold production. Reservoir modeling intends to minimize the risk factor, maximize production, and help determine the location for infill drillings. Cold heavy oil production with sand (CHOPS) is a method for enhancing primary production from heavy oil reservoirs. Gravitational forces, natural fluid pressure gradients and foamy oil flow phenomena are the major driving forces of the CHOPS mechanism. Finally, Reservoir characterization allows better understanding of permeability and porosity prediction.

  12. Evaluation of optimal reservoir prospectivity using acoustic-impedance model inversion: A case study of an offshore field, western Niger Delta, Nigeria

    Directory of Open Access Journals (Sweden)

    Kehinde D. Oyeyemi

    2017-12-01

    Full Text Available The evaluation of economic potential of any hydrocarbon field involves the understanding of the reservoir lithofacies and porosity variations. This in turns contributes immensely towards subsequent reservoir management and field development. In this study, integrated 3D seismic data and well log data were employed to assess the quality and prospectivity of the delineated reservoirs (H1–H5 within the OPO field, western Niger Delta using a model-based seismic inversion technique. The model inversion results revealed four distinct sedimentary packages based on the subsurface acoustic impedance properties and shale contents. Low acoustic impedance model values were associated with the delineated hydrocarbon bearing units, denoting their high porosity and good quality. Application of model-based inverted velocity, density and acoustic impedance properties on the generated time slices of reservoirs also revealed a regional fault and prospects within the field. Keywords: Acoustic impedance, Reservoir characterization, Seismic inversion, Hydrocarbon exploration, Niger Delta

  13. Application of advanced reservoir characterization, simulation, and production optimization strategies to maximize recovery in slope and basin clastic reservoirs, West Texas (Delaware Basin), Class III

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, Shirley P.; Flanders, William A.; Zirczy, Helena H.

    2000-05-24

    The objective of this Class 3 project was to demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost effective way to recover a higher percentage of the original oil in place through strategic placement of infill wells and geologically based field development. Phase 1 of the project, reservoir characterization, was completed this year, and Phase 2 began. The project is focused on East Ford field, a representative Delaware Mountain Group field that produces from the upper Bell Canyon Formation (Ramsey sandstone). The field, discovered in 1960, is operated by Oral Petco, Inc., as the East Ford unit. A CO{sub 2} flood is being conducted in the unit, and this flood is the Phase 2 demonstration for the project.

  14. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin)

    International Nuclear Information System (INIS)

    Dutton, Shirley P.

    1999-01-01

    The objective of this Class 3 project was demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost effective way to recover a higher percentage of the original oil in place through strategic placement of infill wells and geologically based field development. Project objectives are divided into two main phases. The original objectives of the reservoir-characterization phase of the project were (1) to provide a detailed understanding of the architecture and heterogeneity of two representative fields of the Delaware Mountain Group, Geraldine Ford and Ford West, which produce from the Bell Canyon and Cherry Canyon Formations, respectively, (2) to chose a demonstration area in one of the fields, and (3) to simulate a CO 2 flood in the demonstration area

  15. A Methodology to Integrate Magnetic Resonance and Acoustic Measurements for Reservoir Characterization

    Energy Technology Data Exchange (ETDEWEB)

    Parra, J.O.

    2001-01-26

    The objective of this project was to develop an advanced imaging method, including pore scale imaging, to integrate magnetic resonance (MR) techniques and acoustic measurements to improve predictability of the pay zone in two hydrocarbon reservoirs. This was accomplished by extracting the fluid property parameters using MR laboratory measurements and the elastic parameters of the rock matrix from acoustic measurements to create poroelastic models of different parts of the reservoir. Laboratory measurements were compared with petrographic analysis results to determine the relative roles of petrographic elements such as porosity type, mineralogy, texture, and distribution of clay and cement in creating permeability heterogeneity.

  16. Application of Simultaneous Inversion Characterizing Reservoir Properties in X Field, Sabah Basin

    Science.gov (United States)

    Xiang, Lee Ming; Almanna Lubis, Luluan

    2017-10-01

    X field located between the East Baram Delta and Southern Inboard Belt, which is elongated northwest to southeast direction in Middle Miocene Sabah Basin. Previous studies were unable to differentiate the lithology and fluid distribution in the field by using conventional reservoir characterization approaches for example amplitude versus offset (AVO) analysis and post-stack deterministic inversion due to the low contrast in P-impedance between gas sand and shale. Thus, the goal of this approach is to obtain a reliable estimation of P wave velocity (VP). S-wave velocity (Vs), and density (ƿ). From these parameters, we predict the fluid and lithology properties for better reservoir characterization. A feasibility analysis was conducted and the results show that prediction of the hydrocarbon reservoir in X field is feasible using P-impedance and Vp/Vs. Consequently, the simultaneous inversion is carried out to derive the rock properties such as density, P-impedance, S-impedance, Lambda-rho (λƿ) (Incompressibility), and Mu-rho (µƿ) (Rigidity). The results from this study demonstrate the effectiveness of simultaneous inversion and the best parameters for enhancing the resolution and characterizing the hydrocarbon sand layer of the prospect.

  17. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2003-09-25

    The University of Alabama in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company are undertaking an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling that utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary objective of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. The principal research effort for Year 3 of the project has been reservoir characterization, 3-D modeling, testing of the geologic-engineering model, and technology transfer. This effort has included six tasks: (1) the study of seismic attributes, (2) petrophysical characterization, (3) data integration, (4) the building of the geologic-engineering model, (5) the testing of the geologic-engineering model and (6) technology transfer. This work was scheduled for completion in Year 3. Progress on the project is as follows: geoscientific reservoir characterization is completed. The architecture, porosity types and heterogeneity of the reef and shoal reservoirs at Appleton and Vocation Fields have been characterized using geological and geophysical data. The study of rock-fluid interactions has been completed. Observations regarding the diagenetic

  18. Multi-Attribute Seismic/Rock Physics Approach to Characterizing Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Gary Mavko

    2004-11-30

    Most current seismic methods to seismically characterize fractures in tight reservoirs depend on a few anisotropic wave propagation signatures that can arise from aligned fractures. While seismic anisotropy can be a powerful fracture diagnostic, a number of situations can lessen its usefulness or introduce interpretation ambiguities. Fortunately, laboratory and theoretical work in rock physics indicates that a much broader spectrum of fracture seismic signatures can occur, including a decrease in P- and S-wave velocities, a change in Poisson's ratio, an increase in velocity dispersion and wave attenuation, as well as well as indirect images of structural features that can control fracture occurrence. The goal of this project was to demonstrate a practical interpretation and integration strategy for detecting and characterizing natural fractures in rocks. The approach was to exploit as many sources of information as possible, and to use the principles of rock physics as the link among seismic, geologic, and log data. Since no single seismic attribute is a reliable fracture indicator in all situations, the focus was to develop a quantitative scheme for integrating the diverse sources of information. The integrated study incorporated three key elements: The first element was establishing prior constraints on fracture occurrence, based on laboratory data, previous field observations, and geologic patterns of fracturing. The geologic aspects include analysis of the stratigraphic, structural, and tectonic environments of the field sites. Field observations and geomechanical analysis indicates that fractures tend to occur in the more brittle facies, for example, in tight sands and carbonates. In contrast, strain in shale is more likely to be accommodated by ductile flow. Hence, prior knowledge of bed thickness and facies architecture, calibrated to outcrops, are powerful constraints on the interpreted fracture distribution. Another important constraint is that

  19. Silurian "Clinton" Sandstone Reservoir Characterization for Evaluation of CO2-EOR Potential in the East Canton Oil Field, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Ronald; Wicks, John; Perry, Christopher

    2009-12-30

    The purpose of this study was to evaluate the efficacy of using CO2-enhanced oil recovery (EOR) in the East Canton oil field (ECOF). Discovered in 1947, the ECOF in northeastern Ohio has produced approximately 95 million barrels (MMbbl) of oil from the Silurian “Clinton” sandstone. The original oil-in-place (OOIP) for this field was approximately 1.5 billion bbl and this study estimates by modeling known reservoir parameters, that between 76 and 279 MMbbl of additional oil could be produced through secondary recovery in this field, depending on the fluid and formation response to CO2 injection. A CO2 cyclic test (“Huff-n-Puff”) was conducted on a well in Stark County to test the injectivity in a “Clinton”-producing oil well in the ECOF and estimate the dispersion or potential breakthrough of the CO2 to surrounding wells. Eighty-one tons of CO2 (1.39 MMCF) were injected over a 20-hour period, after which the well was shut in for a 32-day “soak” period before production was resumed. Results demonstrated injection rates of 1.67 MMCF of gas per day, which was much higher than anticipated and no CO2 was detected in gas samples taken from eight immediately offsetting observation wells. All data collected during this test was analyzed, interpreted, and incorporated into the reservoir characterization study and used to develop the geologic model. The geologic model was used as input into a reservoir simulation performed by Fekete Associates, Inc., to estimate the behavior of reservoir fluids when large quantities of CO2 are injected into the “Clinton” sandstone. Results strongly suggest that the majority of the injected CO2 entered the matrix porosity of the reservoir pay zones, where it diffused into the oil. Evidence includes: (A) the volume of injected CO2 greatly exceeded the estimated capacity of the hydraulic fracture and natural fractures; (B) there was a gradual injection and pressure rate build-up during the test; (C) there was a subsequent

  20. Silurian "Clinton" Sandstone Reservoir Characterization for Evaluation of CO2-EOR Potential in the East Canton Oil Field, Ohio

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Riley; John Wicks; Christopher Perry

    2009-12-30

    The purpose of this study was to evaluate the efficacy of using CO2-enhanced oil recovery (EOR) in the East Canton oil field (ECOF). Discovered in 1947, the ECOF in northeastern Ohio has produced approximately 95 million barrels (MMbbl) of oil from the Silurian 'Clinton' sandstone. The original oil-in-place (OOIP) for this field was approximately 1.5 billion bbl and this study estimates by modeling known reservoir parameters, that between 76 and 279 MMbbl of additional oil could be produced through secondary recovery in this field, depending on the fluid and formation response to CO2 injection. A CO2 cyclic test ('Huff-n-Puff') was conducted on a well in Stark County to test the injectivity in a 'Clinton'-producing oil well in the ECOF and estimate the dispersion or potential breakthrough of the CO2 to surrounding wells. Eighty-one tons of CO2 (1.39 MMCF) were injected over a 20-hour period, after which the well was shut in for a 32-day 'soak' period before production was resumed. Results demonstrated injection rates of 1.67 MMCF of gas per day, which was much higher than anticipated and no CO2 was detected in gas samples taken from eight immediately offsetting observation wells. All data collected during this test was analyzed, interpreted, and incorporated into the reservoir characterization study and used to develop the geologic model. The geologic model was used as input into a reservoir simulation performed by Fekete Associates, Inc., to estimate the behavior of reservoir fluids when large quantities of CO2 are injected into the 'Clinton' sandstone. Results strongly suggest that the majority of the injected CO2 entered the matrix porosity of the reservoir pay zones, where it diffused into the oil. Evidence includes: (A) the volume of injected CO2 greatly exceeded the estimated capacity of the hydraulic fracture and natural fractures; (B) there was a gradual injection and pressure rate build-up during the test

  1. Application of advanced reservoir characterization, simulation, and production optimization strategies to maximize recovery in slope and basin clastic reservoirs, west Texas (Delaware Basin). Annual progress report, March 31, 1995--March 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, S.P.; Hovorka, S.D.; Cole, A.G.

    1996-08-01

    The objective of this Class III project is to demonstrate that detailed reservoir characterization of clastic reservoirs in basinal sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost-effective way to recover more of the original oil in place by strategic infill-well placement and geologically based field development. Reservoirs in the Delaware Mountain Group have low producibility (average recovery <14 percent of the original oil in place) because of a high degree of vertical and lateral heterogeneity caused by depositional processes and post-depositional diagenetic modification. Detailed correlations of the Ramsey sandstone reservoirs in Geraldine Ford field suggest that lateral sandstone continuity is less than interpreted by previous studies. The degree of lateral heterogeneity in the reservoir sandstones suggests that they were deposited by eolian-derived turbidites. According to the eolian-derived turbidite model, sand dunes migrated across the exposed shelf to the shelf break during sea-level lowstands and provided well sorted sand for turbidity currents or grain flows into the deep basin.

  2. Hydrologic characterization of Bushy Park Reservoir, South Carolina, 2013–15

    Science.gov (United States)

    Conrads, Paul; Petkewich, Matthew D.; Falls, W. Fred; Lanier, Timothy H.

    2017-06-14

    The Bushy Park Reservoir is a relatively shallow impoundment in a semi-tropical climate and is the principal water supply for the 400,000 people of the city of Charleston, South Carolina, and the surrounding areas including the Bushy Park Industrial Complex. Although there is an adequate supply of freshwater in the reservoir, taste-and-odor water-quality issues are a concern. The U.S. Geological Survey conducted an investigation in cooperation with the Charleston Water System to study the hydrology and hydrodynamics of the Bushy Park Reservoir to identify factors affecting water-quality conditions. Specifically, five areas for monitoring and (or) analysis were addressed: (1) hydrologic monitoring of the reservoir to establish a water budget, (2) flow monitoring in the tunnels to compute flow from Bushy Park Reservoir and at critical distribution junctions, (3) water-quality sampling, profiling, and continuous monitoring to identify the causes of taste-and-odor occurrence, (4) technical evaluation of appropriate hydrodynamic and water-quality simulation models for the reservoir, and (5) preliminary evaluation of alternative reservoir operations scenarios.This report describes the hydrodynamic and hydrologic data collected from 2013 to 2015 to support the application and calibration of a three-dimensional hydrodynamic model and the water-quality monitoring and analysis to gain insight into the principal causes of the Bushy Park Reservoir taste-and-odor episodes. The existing U.S. Geological Survey real-time network on the West Branch of the Cooper River was augmented with a tidal flow gage on Durham Canal Back River, and Foster Creek. The Charleston Water System intake structure was instrumented to collect water-level, water temperature (top and bottom probes), specific conductance (top and bottom probes), wind speed and direction, and photosynthetically active radiation data. In addition to the gages attached to fixed structures, four bottom-mounted velocity

  3. Modelling of fractured reservoirs. Case of multi-scale media; Modelisation des reservoirs fractures. Cas des milieux multi-echelles

    Energy Technology Data Exchange (ETDEWEB)

    Henn, N.

    2000-12-13

    Some of the most productive oil and gas reservoirs are found in formations crossed by multi-scale fractures/faults. Among them, conductive faults may closely control reservoir performance. However, their modelling encounters numerical and physical difficulties linked with (a) the necessity to keep an explicit representation of faults through small-size grid blocks, (b) the modelling of multiphase flow exchanges between the fault and the neighbouring medium. In this thesis, we propose a physically-representative and numerically efficient modelling approach in order to incorporate sub-vertical conductive faults in single and dual-porosity simulators. To validate our approach and demonstrate its efficiency, simulation results of multiphase displacements in representative field sector models are presented. (author)

  4. 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.

  5. Effect of coherence of nonthermal reservoirs on heat transport in a microscopic collision model

    Science.gov (United States)

    Li, Lei; Zou, Jian; Li, Hai; Xu, Bao-Ming; Wang, Yuan-Mei; Shao, Bin

    2018-02-01

    We investigate the heat transport between two nonthermal reservoirs based on a microscopic collision model. We consider a bipartite system consisting of two identical subsystems, and each subsystem interacts with its own local reservoir, which consists of a large collection of initially uncorrelated ancillas. Then a heat transport is formed between two reservoirs by a sequence of pairwise collisions (intersubsystem and subsystem-local reservoir). In this paper we consider two kinds of the reservoir's initial states: the thermal state and the state with coherence whose diagonal elements are the same as that of the thermal state and the off-diagonal elements are nonzero. In this way, we define the effective temperature of the reservoir with coherence according to its diagonal elements. We find that for two reservoirs having coherence the direction of the steady current of heat is different for different phase differences between the two initial states of two reservoirs, especially the heat can transfer from the "cold reservoir" to the "hot reservoir" in the steady regime for particular phase difference. In the limit of the effective temperature difference between the two reservoirs Δ T →0 , for most of the phase differences, the steady heat current increases with the increase of effective temperature until it reaches the high effective temperature limit, while for the thermal state or particular phase difference the steady heat current decreases with the increase of temperature at high temperatures, and in this case the conductance can be obtained.

  6. Strontium isotopic signatures of oil-field waters: Applications for reservoir characterization

    Science.gov (United States)

    Barnaby, R.J.; Oetting, G.C.; Gao, G.

    2004-01-01

    The 87Sr/86Sr compositions of formation waters that were collected from 71 wells producing from a Pennsylvanian carbonate reservoir in New Mexico display a well-defined distribution, with radiogenic waters (up to 0.710129) at the updip western part of the reservoir, grading downdip to less radiogenic waters (as low as 0.708903 to the east. Salinity (2800-50,000 mg/L) displays a parallel trend; saline waters to the west pass downdip to brackish waters. Elemental and isotopic data indicate that the waters originated as meteoric precipitation and acquired their salinity and radiogenic 87Sr through dissolution of Upper Permian evaporites. These meteoric-derived waters descended, perhaps along deeply penetrating faults, driven by gravity and density, to depths of more than 7000 ft (2100 m). The 87 Sr/86Sr and salinity trends record influx of these waters along the western field margin and downdip flow across the field, consistent with the strong water drive, potentiometric gradient, and tilted gas-oil-water contacts. The formation water 87Sr/86Sr composition can be useful to evaluate subsurface flow and reservoir behavior, especially in immature fields with scarce pressure and production data. In mature reservoirs, Sr Sr isotopes can be used to differentiate original formation water from injected water for waterflood surveillance. Strontium isotopes thus provide a valuable tool for both static and dynamic reservoir characterization in conjunction with conventional studies using seismic, log, core, engineering, and production data. Copyright ??2004. The American Association of Petroleum Geologist. All rights reserved.

  7. Markov random fields simulation: an introduction to the stochastic modelling of petroleum reservoirs; Simulacao de campos aleatorios markovianos: uma introducao voltada a modelagem estocastica de reservatorios de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Saldanha Filho, Paulo Carlos

    1998-02-01

    Stochastic simulation has been employed in petroleum reservoir characterization as a modeling tool able to reconcile information from several different sources. It has the ability to preserve the variability of the modeled phenomena and permits transference of geological knowledge to numerical models of flux, whose predictions on reservoir constitute the main basis for reservoir management decisions. Several stochastic models have been used and/or suggested, depending on the nature of the phenomena to be described. Markov Random Fields (MRFs) appear as an alternative for the modeling of discrete variables, mainly reservoirs with mosaic architecture of facies. In this dissertation, the reader is introduced to the stochastic modeling by MRFs in a generic sense. The main aspects of the technique are reviewed. MRF Conceptual Background is described: its characterization through the Markovian property and the equivalence to Gibbs distributions. The framework for generic modeling of MRFs is described. The classical models of Ising and Potts-Strauss are specific in this context and are related to models of Ising and Potts-Strauss are specific in this context and are related to models used in petroleum reservoir characterization. The problem of parameter estimation is discussed. The maximum pseudolikelihood estimators for some models are presented. Estimators for two models useful for reservoir characterization are developed, and represent a new contribution to the subject. Five algorithms for the Conditional Simulation of MRFs are described: the Metropolis algorithm, the algorithm of German and German (Gibbs sampler), the algorithm of Swendsen-Wang, the algorithm of Wolff, and the algorithm of Flinn. Finally, examples of simulation for some of the models discussed are presented, along with their implications on the modelling of petroleum reservoirs. (author)

  8. Characterization of water quality in Bushy Park Reservoir, South Carolina, 2013–15

    Science.gov (United States)

    Conrads, Paul A.; Journey, Celeste A.; Petkewich, Matthew D.; Lanier, Timothy H.; Clark, Jimmy M.

    2018-04-25

    The Bushy Park Reservoir is the principal water supply for 400,000 people in the greater Charleston, South Carolina, area, which includes homes as well as businesses and industries in the Bushy Park Industrial Complex. Charleston Water System and the U.S. Geological Survey conducted a cooperative study during 2013–15 to assess the circulation of Bushy Park Reservoir and its effects on water-quality conditions, specifically, recurring taste-and-odor episodes. This report describes the water-quality data collected for the study that included a combination of discrete water-column sampling at seven locations in the reservoir and longitudinal water-quality profiling surveys of the reservoir and tributaries to characterize the temporal and spatial water-quality dynamics of Bushy Park Reservoir. Water-quality profiling surveys were conducted with an autonomous underwater vehicle equipped with a multiparameter water-quality-sonde bulkhead. Data collected by the autonomous underwater vehicle included water temperature, dissolved oxygen, pH, specific conductance, turbidity, total chlorophyll as fluorescence (estimate of algal biomass), and phycocyanin as fluorescence (estimate of cyanobacteria biomass) data.Characterization of the water-quality conditions in the reservoir included comparison to established State nutrient guidelines, identification of any spatial and seasonal variation in water-quality conditions and phytoplankton community structures, and assessment of the degree of influence of water-quality conditions related to Foster Creek and Durham Canal inflows, especially during periods of elevated taste-and-odor concentrations. Depth-profile and autonomous underwater vehicle survey data were used to identify areas within the reservoir where greater phytoplankton and cyanobacteria densities were most likely occurring.Water-quality survey results indicated that Bushy Park Reservoir tended to stratify thermally at a depth of about 20 feet from June to early October

  9. Modeling Tools for Drilling, Reservoir Navigation, and Formation Evaluation

    Directory of Open Access Journals (Sweden)

    Sushant Dutta

    2012-06-01

    successfully explains the unusual curve separations of an array laterolog tool in a shale-gas formation. The third example uses two-dimensional (2-D and 3-D modeling to prove the efficacy of a new borehole technology for reservoir monitoring.

  10. [Application of data fusion of microscopic spectral imaging in reservoir characterization].

    Science.gov (United States)

    Li, Jing; Zha, Ming; Guo, Yuan-Ling; Chen, Yong

    2011-10-01

    In recent years, spectral imaging technique has been applied widely in mineralogy and petrology. The technique combines the spectral technique with imaging technique. The samples can be analyzed and recognized both in spectra and space by using the technique. However, the problem is how to acquire the needful information from a large number of data of spectral imaging, and how to enhance the needful information. In the present paper, the experimental data were processed by using the technique of data fusion of microscopic spectral imaging. The space distribution map of chemical composition and physical parameters of samples were obtained. The result showed that the distribution of different hydrocarbon in the reservoirs, pore connectivity, etc. were revealed well. The technique of data fusion of microscopic spectral imaging provided a new method for reservoir characterization.

  11. Integrated reservoir characterization of a heterogeneous channel sandstone : the Duchess Lower Manville X pool

    Energy Technology Data Exchange (ETDEWEB)

    Potocki, D.; Raychaudhuri, I.; Thorburn, L. [PanCanadian Petroleum Ltd. (Canada); Galas, C.; King, H.

    1999-01-01

    The Basal Quartz formation of the Duchess Lower Mannville X pool located in southern Alberta was characterized to determine if the reservoir was a good candidate for waterflooding. Twenty performance predictions were run. The Basal Quartz reservoir sandstones have large unanticipated intrawell and interwell variations in log derived porosity and resistivity. An extensive gas cap was also found in most of the wells. Most wells were producing with a high GOR despite the thick oil zone. It was concluded that conversion of selected wells to injection and horizontal infill wells would increase the oil recovery, but due to geological heterogeneity, the gas cap and a high in situ oil viscosity, the pool could not be considered to be a good candidate for waterflooding. 3 refs., 12 figs.

  12. Characterizing hydraulic fractures in shale gas reservoirs using transient pressure tests

    Directory of Open Access Journals (Sweden)

    Cong Wang

    2015-06-01

    This work presents an unconventional gas reservoir simulator and its application to quantify hydraulic fractures in shale gas reservoirs using transient pressure data. The numerical model incorporates most known physical processes for gas production from unconventional reservoirs, including two-phase flow of liquid and gas, Klinkenberg effect, non-Darcy flow, and nonlinear adsorption. In addition, the model is able to handle various types and scales of fractures or heterogeneity using continuum, discrete or hybrid modeling approaches under different well production conditions of varying rate or pressure. Our modeling studies indicate that the most sensitive parameter of hydraulic fractures to early transient gas flow through extremely low permeability rock is actually the fracture-matrix contacting area, generated by fracturing stimulation. Based on this observation, it is possible to use transient pressure testing data to estimate the area of fractures generated from fracturing operations. We will conduct a series of modeling studies and present a methodology using typical transient pressure responses, simulated by the numerical model, to estimate fracture areas created or to quantity hydraulic fractures with traditional well testing technology. The type curves of pressure transients from this study can be used to quantify hydraulic fractures in field application.

  13. FRACTURED RESERVOIR E&P IN ROCKY MOUNTAIN BASINS: A 3-D RTM MODELING APPROACH

    Energy Technology Data Exchange (ETDEWEB)

    P. Ortoleva; J. Comer; A. Park; D. Payne; W. Sibo; K. Tuncay

    2001-11-26

    Key natural gas reserves in Rocky Mountain and other U.S. basins are in reservoirs with economic producibility due to natural fractures. In this project, we evaluate a unique technology for predicting fractured reservoir location and characteristics ahead of drilling based on a 3-D basin/field simulator, Basin RTM. Recommendations are made for making Basin RTM a key element of a practical E&P strategy. A myriad of reaction, transport, and mechanical (RTM) processes underlie the creation, cementation and preservation of fractured reservoirs. These processes are often so strongly coupled that they cannot be understood individually. Furthermore, sedimentary nonuniformity, overall tectonics and basement heat flux histories make a basin a fundamentally 3-D object. Basin RTM is the only 3-D, comprehensive, fully coupled RTM basin simulator available for the exploration of fractured reservoirs. Results of Basin RTM simulations are presented, that demonstrate its capabilities and limitations. Furthermore, it is shown how Basin RTM is a basis for a revolutionary automated methodology for simultaneously using a range of remote and other basin datasets to locate reservoirs and to assess risk. Characteristics predicted by our model include reserves and composition, matrix and fracture permeability, reservoir rock strength, porosity, in situ stress and the statistics of fracture aperture, length and orientation. Our model integrates its input data (overall sedimentation, tectonic and basement heat flux histories) via the laws of physics and chemistry that describe the RTM processes to predict reservoir location and characteristics. Basin RTM uses 3-D, finite element solutions of the equations of rock mechanics, organic and inorganic diagenesis and multi-phase hydrology to make its predictions. As our model predicts reservoir characteristics, it can be used to optimize production approaches (e.g., assess the stability of horizontal wells or vulnerability of fractures to

  14. Modelling of sedimentation processes inside Roseires Reservoir (Sudan) (abstract)

    NARCIS (Netherlands)

    Ali, Y.S.A.; Omer, A.Y.A.; Crosato, A.

    2013-01-01

    Roseires Reservoir is located on the Blue Nile River, in Sudan (figure 1). It is the first trap to the sediments coming from the upper catchment in Ethiopia, which suffers from high erosion and desertification problems. The reservoir lost already more than one third of its storage capacity due to

  15. Modelling of sedimentation processes inside Roseires Reservoir (Sudan) (discussion)

    NARCIS (Netherlands)

    Omer, A.Y.A.; Ali, Y.S.A.; Roelvink, J.A.; Dastgheib, A.; Paron, P.; Crosato, A.

    2014-01-01

    Discussion paper. Roseires Reservoir, located on the Blue Nile River, in Sudan, is the first trap to the sediments coming from the upper catchment in Ethiopia, which suffers from high erosion and desertification problems. The reservoir lost already more than one third of its 5 storage capacity due

  16. Modelling of sedimentation processes inside Roseires Reservoir (Sudan)

    NARCIS (Netherlands)

    Omer, A.Y.A.; Ali, Y.S.A.; Roelvink, J.A.; Dastgheib, A.; Paron, P.; Crosato, A.

    2015-01-01

    Roseires Reservoir, located on the Blue Nile River in Sudan, is the first trap to the sediments coming from the vast upper river catchment in Ethiopia, which suffers from high erosion and desertification problems. The reservoir has already lost more than one-third of its storage capacity due to

  17. BEKWAAM, a model fit for reservoir design and management

    NARCIS (Netherlands)

    Benoist, A.P.; Brinkman, A.G.; Diepenbeek, van P.M.J.A.; Waals, J.M.J.

    1998-01-01

    In the Province of Limburg in the Netherlands a new reservoir will be used for the drinking water production of 20 million m3 per annum from the year 2002. With the use of this reservoir the WML is shifting towards the use of surface water (River Meuse) as primary source instead of ground water.

  18. 3-D RESERVOIR AND STOCHASTIC FRACTURE NETWORK MODELING FOR ENHANCED OIL RECOVERY, CIRCLE RIDGE PHOSPHORIA/TENSLEEP RESERVOIR, WIND RIVER RESERVATION, ARAPAHO AND SHOSHONE TRIBES, WYOMING

    Energy Technology Data Exchange (ETDEWEB)

    Paul La Pointe; Jan Hermanson; Robert Parney; Thorsten Eiben; Mike Dunleavy; Ken Steele; John Whitney; Darrell Eubanks; Roger Straub

    2002-11-18

    This report describes the results made in fulfillment of contract DE-FG26-00BC15190, ''3-D Reservoir and Stochastic Fracture Network Modeling for Enhanced Oil Recovery, Circle Ridge Phosphoria/Tensleep Reservoir, Wind River Reservation, Arapaho and Shoshone Tribes, Wyoming''. The goal of this project is to improve the recovery of oil from the Tensleep and Phosphoria Formations in Circle Ridge Oilfield, located on the Wind River Reservation in Wyoming, through an innovative integration of matrix characterization, structural reconstruction, and the characterization of the fracturing in the reservoir through the use of discrete fracture network models. Fields in which natural fractures dominate reservoir permeability, such as the Circle Ridge Field, often experience sub-optimal recovery when recovery processes are designed and implemented that do not take advantage of the fracture systems. For example, a conventional waterflood in a main structural block of the Field was implemented and later suspended due to unattractive results. It is estimated that somewhere less than 20% of the OOIP in the Circle Ridge Field have been recovered after more than 50 years' production. Marathon Oil Company identified the Circle Ridge Field as an attractive candidate for several advanced IOR processes that explicitly take advantage of the natural fracture system. These processes require knowledge of the distribution of matrix porosity, permeability and oil saturations; and understanding of where fracturing is likely to be well-developed or poorly developed; how the fracturing may compartmentalize the reservoir; and how smaller, relatively untested subthrust fault blocks may be connected to the main overthrust block. For this reason, the project focused on improving knowledge of the matrix properties, the fault block architecture and to develop a model that could be used to predict fracture intensity, orientation and fluid flow/connectivity properties. Knowledge

  19. CHARACTERIZATION OF IN-SITU STRESS AND PERMEABILITY IN FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Daniel R. Burns; M. Nafi Toksoz

    2005-02-04

    Numerical modeling and field data tests are presented on the Transfer Function/Scattering Index Method for estimating fracture orientation and density in subsurface reservoirs from the ''coda'' or scattered energy in the seismic trace. Azimuthal stacks indicate that scattered energy is enhanced along the fracture strike direction. A transfer function method is used to more effectively indicate fracture orientation. The transfer function method, which involves a comparison of the seismic signature above and below a reservoir interval, effectively eliminates overburden effects and acquisition imprints in the analysis. The transfer function signature is simplified into a scattering index attribute value that gives fracture orientation and spatial variations of the fracture density within a field. The method is applied to two field data sets, a 3-D Ocean Bottom Cable (OBC) seismic data set from an offshore fractured carbonate reservoir in the Adriatic Sea and a 3-D seismic data set from an onshore fractured carbonate field in the Middle East. Scattering index values are computed in both fields at the reservoir level, and the results are compared to borehole breakout data and Formation MicroImager (FMI) logs in nearby wells. In both cases the scattering index results are in very good agreement with the well data. Field data tests and well validation will continue. In the area of technology transfer, we have made presentations of our results to industry groups at MIT technical review meetings, international technical conferences, industry workshops, and numerous exploration and production company visits.

  20. Fast Multiscale Reservoir Simulations using POD-DEIM Model Reduction

    KAUST Repository

    Ghasemi, Mohammadreza

    2015-02-23

    In this paper, we present a global-local model reduction for fast multiscale reservoir simulations in highly heterogeneous porous media with applications to optimization and history matching. Our proposed approach identifies a low dimensional structure of the solution space. We introduce an auxiliary variable (the velocity field) in our model reduction that allows achieving a high degree of model reduction. The latter is due to the fact that the velocity field is conservative for any low-order reduced model in our framework. Because a typical global model reduction based on POD is a Galerkin finite element method, and thus it can not guarantee local mass conservation. This can be observed in numerical simulations that use finite volume based approaches. Discrete Empirical Interpolation Method (DEIM) is used to approximate the nonlinear functions of fine-grid functions in Newton iterations. This approach allows achieving the computational cost that is independent of the fine grid dimension. POD snapshots are inexpensively computed using local model reduction techniques based on Generalized Multiscale Finite Element Method (GMsFEM) which provides (1) a hierarchical approximation of snapshot vectors (2) adaptive computations by using coarse grids (3) inexpensive global POD operations in a small dimensional spaces on a coarse grid. By balancing the errors of the global and local reduced-order models, our new methodology can provide an error bound in simulations. Our numerical results, utilizing a two-phase immiscible flow, show a substantial speed-up and we compare our results to the standard POD-DEIM in finite volume setup.

  1. Modeling of CO2 migration injected in Weyburn oil reservoir

    International Nuclear Information System (INIS)

    Zhou Wei; Stenhouse, M.J.; Arthur, R.

    2008-01-01

    Injecting CO 2 into oil and gas field is a way to enhance oil recovery (EOR) as well as mitigate global warming effect by permanently storing the greenhouse gas into underground. This paper details the models and results of simulating the long-term migration of CO 2 injected into the Weyburn field for both Enhanced Oil Recovery operations and CO 2 sequestration. A System Model was established to define the spatial and temporal extents of the analysis. The Base Scenario was developed to identify key processes, features, and events (FEPs) for the expected evolution of the storage system. A compositional reservoir simulator with equations-of-states (EOS) was used as the modeling tool in order to simulate multiphase, multi-component flow and transport coupled with CO 2 mass partitioning into oil, gas, and water phases. We apply a deterministic treatment to CO 2 migration in the geosphere (natural pathways), whereas the variability of abandoned wells (man-made pathways) necessitates a stochastic treatment. The simulation result was then used to carry out consequence analysis to the local environment. (authors)

  2. Application of artificial intelligence to reservoir characterization: An interdisciplinary approach. [Quarterly progress report], January 1--March 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Kelkar, B.G.; Gamble, R.F.; Kerr, D.R.; Thompson, L.G.; Shenoi, S.

    1994-06-01

    The basis of this research is to apply novel techniques from Artificial Intelligence and Expert Systems in capturing, integrating and articulating key knowledge from geology, geostatistics, and petroleum engineering to develop accurate descriptions of petroleum reservoirs. The ultimate goal is to design and implement a single powerful expert system for use by small producers and independents to efficiently exploit reservoirs. The overall project plan to design the system to create integrated reservoir descriptions begins by initially developing an Al-based methodology for producing large-scale reservoir descriptions generated interactively from geology and well test data. Parallel to this task is a second task that develops an Al-based methodology that uses facies-biased information to generate small-scale descriptions of reservoir properties such as permeability and porosity. The third task involves consolidation and integration of the large-scale and small-scale methodologies to produce reservoir descriptions honoring all the available data. The final task will be technology transfer. With this plan, we have carefully allocated and sequenced the activities involved in each of the tasks to promote concurrent progress towards the research objectives. Moreover, the project duties are divided among the faculty member participants. Graduate students will work in teams with faculty members. The results of the integration are not merely limited to obtaining better characterizations of individual reservoirs. They have the potential to significantly impact and advance the discipline of reservoir characterization itself.

  3. Reactive Transport Modeling and Geophysical Monitoring of Bioclogging at Reservoir Scale

    Science.gov (United States)

    Surasani, V.; Commer, M.; Ajo Franklin, J. B.; Li, L.; Hubbard, S. S.

    2012-12-01

    In Microbial-Enhanced-Hydrocarbon-Recovery (MEHR), preferential bioclogging targets the growth of the biofilms (def. immobilized biopolymers with active cells embodied in it) in highly permeable thief zones to enhance sweep efficiency in oil reservoirs. During MEHR, understanding and controlling bioclogging is hindered by the lack of advanced modeling and monitoring tools; these deficiencies contribute to suboptimal performance. Our focus in this study was on developing a systematic approach to understand and monitor bioclogging at the reservoir scale using a combination of reactive transport modeling and geophysical imaging tools (EM & seismic). In this study, we created a realistic reservoir model from a heterogeneous gas reservoir in the Southern Sacramento basin, California; the model well (Citizen Green #1) was characterized using sonic, electrical, nuclear, and NMR logs for hydrologic and geophysical properties. From the simplified 2D log data model, a strip of size 150m x75m with several high permeability streaks is identified for bioclogging simulation experiments. From the NMR log data it is observed that a good linear correlation exist between logarithmic permeability (0.55- 3.34 log (mD)) versus porosity (0.041-0.28). L. mesenteroides was chosen as the model bacteria. In the presence of sucrose, it enzymatically catalyzes the production of dextran, a useful bioclogging agent. Using microbial kinetics from our laboratory experiment and reservoir heterogeneity, a reactive transport model (RTM) is established for two kinds of bioclogging treatments based on whether microbes are present in situ or are supplied externally. In both cases, sucrose media (1.5 M) is injected at the rate of 1 liter/s for 20 days into the center of high permeable strip to stimulate microbes. Simulations show that the high dextran production was deep into the formation from the injection well. This phenomenon can be explained precisely with bacterial kinetics and injection rate. In

  4. Sweet spot identification and smart development -An integrated reservoir characterization study of a posidonia shale of a posidonia shale outcrop analogue

    NARCIS (Netherlands)

    Veen, J.H. ten; Verreussel, R.M.C.H.; Ventra, D.; Zijp, M.H.A.A.

    2014-01-01

    Shale gas reservoir stimulation procedures (e.g. hydraulic fracturing) require upfront prediction and planning that should be supported by a comprehensive reservoir characterization. Therefore, understanding shale depositional processes and associated vertical and lateral sedimentological

  5. Simulation of Gas Transport in Tight/Shale Gas Reservoirs by a Multicomponent Model Based on PEBI Grid

    Directory of Open Access Journals (Sweden)

    Longjun Zhang

    2015-01-01

    Full Text Available The ultra-low permeability and nanosize pores of tight/shale gas reservoir would lead to non-Darcy flow including slip flow, transition flow, and free molecular flow, which cannot be described by traditional Darcy’s law. The organic content often adsorbs some gas content, while the adsorbed amount for different gas species is different. Based on these facts, we develop a new compositional model based on unstructured PEBI (perpendicular bisection grid, which is able to characterize non-Darcy flow including slip flow, transition flow, and free molecular flow and the multicomponent adsorption in tight/shale gas reservoirs. With the proposed model, we study the effect of non-Darcy flow, length of the hydraulic fracture, and initial gas composition on gas production. The results show both non-Darcy flow and fracture length have significant influence on gas production. Ignoring non-Darcy flow would underestimate 67% cumulative gas production in lower permeable gas reservoirs. Gas production increases with fracture length. In lower permeable reservoirs, gas production increases almost linearly with the hydraulic fracture length. However, in higher permeable reservoirs, the increment of the former gradually decreases with the increase in the latter. The results also show that the presence of CO2 in the formation would lower down gas production.

  6. Characterization of heterogeneous reservoirs: sentinels method and quantification of uncertainties; Caracterisation des reservoirs heterogenes: methode des sentinelles et quantification des incertitudes

    Energy Technology Data Exchange (ETDEWEB)

    Mezghani, M.

    1999-02-11

    The aim of this thesis is to propose a new inversion method to allow both an improved reservoir characterization and a management of uncertainties. In this approach, the identification of the permeability distribution is conducted using the sentinel method in order to match the pressure data. This approach, based on optimal control theory, can be seen as an alternative of least-squares method. Here, we prove the existence of exact sentinels under regularity hypothesis. From a numerical point of view, we consider regularized sentinels. We suggest a novel approach to update the penalization coefficient in order to improve numerical robustness. Moreover, the flexibility of the sentinel method enables to develop a way to treat noisy pressure data. To deal with geostatistical modelling of permeability distribution, we propose to link the pilot point method with sentinels to reach the identification of permeability. We particularly focus on the optimal location of pilot points. Finally, we present an original method, based on adjoint state computations, to quantify the dynamic data contribution to the characterisation of a calibrated geostatistical model. (author) 67 refs.

  7. Methane hydrate reservoir model around the eastern Nankai trough area offshore Japan

    Energy Technology Data Exchange (ETDEWEB)

    Inamori, T.; Hayashi, M.; Kobayashi, T.; Shimoda, N.; Takano, O.; Takayama, T.; Fujii, T.; Saeki, T. [Japan Oil, Gas and Metals National Corp., Chiba (Japan). Dept. of Technology Research and Development

    2008-07-01

    This paper described a modelling study conducted to characterize gas hydrates in the eastern Nankai trough region near the coast of Japan. Two drilling campaigns were conducted in the region, and a total of 39 boreholes were drilled to obtain logging data. Data from exploratory wells drilled in the region were also presented. Methane hydrate-concentrated zones were delineated using seismic sequence analysis and 3-D seismic surveys. Methane hydrate-bearing sediments corresponded with turbidite sands using logging and coring data. A rock physics model was developed using data obtained from the analyses. The study showed that methane hydrate bearing-sediments near the eastern Nankai trough area are heterogenous and both vertically and horizontally complex, as the sediments were composed of turbidite sands with channel-levee and lobe systems. Sandy intervals had higher levels of methane hydrates than silty or muddy intervals. The reservoirs were divided into 3 distinct types: (1) low-saturation; (2) discontinuous high-saturation; and (3) continuous high-saturation. The reservoirs were delineated by selecting the bottom simulating reflector (BSM) as the top of the hydrate-bearing sediments for the turbidite channel-levee or lobe systems. The hydrate rock physics model was used to develop the matrix support model from the relationship between P and S wave velocities and methane hydrate saturation. 9 refs., 11 figs.

  8. Application of Stochastic Partial Differential Equations to Reservoir Property Modelling

    KAUST Repository

    Potsepaev, R.

    2010-09-06

    Existing algorithms of geostatistics for stochastic modelling of reservoir parameters require a mapping (the \\'uvt-transform\\') into the parametric space and reconstruction of a stratigraphic co-ordinate system. The parametric space can be considered to represent a pre-deformed and pre-faulted depositional environment. Existing approximations of this mapping in many cases cause significant distortions to the correlation distances. In this work we propose a coordinate free approach for modelling stochastic textures through the application of stochastic partial differential equations. By avoiding the construction of a uvt-transform and stratigraphic coordinates, one can generate realizations directly in the physical space in the presence of deformations and faults. In particular the solution of the modified Helmholtz equation driven by Gaussian white noise is a zero mean Gaussian stationary random field with exponential correlation function (in 3-D). This equation can be used to generate realizations in parametric space. In order to sample in physical space we introduce a stochastic elliptic PDE with tensor coefficients, where the tensor is related to correlation anisotropy and its variation is physical space.

  9. Deep microbial life in the Altmark natural gas reservoir: baseline characterization prior CO2 injection

    Science.gov (United States)

    Morozova, Daria; Shaheed, Mina; Vieth, Andrea; Krüger, Martin; Kock, Dagmar; Würdemann, Hilke

    2010-05-01

    Within the framework of the CLEAN project (CO2 Largescale Enhanced gas recovery in the Altmark Natural gas field) technical basics with special emphasis on process monitoring are explored by injecting CO2 into a gas reservoir. Our study focuses on the investigation of the in-situ microbial community of the Rotliegend natural gas reservoir in the Altmark, located south of the city Salzwedel, Germany. In order to characterize the microbial life in the extreme habitat we aim to localize and identify microbes including their metabolism influencing the creation and dissolution of minerals. The ability of microorganisms to speed up dissolution and formation of minerals might result in changes of the local permeability and the long-term safety of CO2 storage. However, geology, structure and chemistry of the reservoir rock and the cap rock as well as interaction with saline formation water and natural gases and the injected CO2 affect the microbial community composition and activity. The reservoir located at the depth of about 3500m, is characterised by high salinity fluid and temperatures up to 127° C. It represents an extreme environment for microbial life and therefore the main focus is on hyperthermophilic, halophilic anaerobic microorganisms. In consequence of the injection of large amounts of CO2 in the course of a commercial EGR (Enhanced Gas Recovery) the environmental conditions (e.g. pH, temperature, pressure and solubility of minerals) for the autochthonous microorganisms will change. Genetic profiling of amplified 16S rRNA genes are applied for detecting structural changes in the community by using PCR- SSCP (PCR-Single-Strand-Conformation Polymorphism) and DGGE (Denaturing Gradient Gel Electrophoresis). First results of the baseline survey indicate the presence of microorganisms similar to representatives from other saline, hot, anoxic, deep environments. However, due to the hypersaline and hyperthermophilic reservoir conditions, cell numbers are low, so that

  10. Characterization of the Campylobacter jejuni population in the barnacle geese reservoir.

    Science.gov (United States)

    Llarena, A-K; Skarp-de Haan, C P A; Rossi, M; Hänninen, M-L

    2015-05-01

    Campylobacter spp. are the most common cause of bacterial gastroenteritis worldwide and have been isolated from a wide number of different hosts and environmental sources. Waterfowl is considered a natural reservoir for this zoonotic bacterium and may act as a potential infection source for human campylobacteriosis. In this study, faecal samples from 924 barnacle geese were tested for the presence of C. jejuni and C. coli. The resulting C. jejuni and C. coli populations were characterized by multilocus sequence typing (MLST), structure analysis by BAPS and phylogenetic analysis based on full genome sequences. The prevalences of C. jejuni in barnacle geese faeces were 11.5% and 23.1% in 2011 and 2012, respectively, and only 0.2% of the samples were positive for C. coli in both years. Furthermore, a possible adaption of the clonal complexes (CCs) ST-702 and ST-1034 to the barnacle geese reservoir was found, as these two CCs represented the majority of the typed isolates and were repeatedly isolated from different flocks at several time-points. Further core genome phylogenetic analysis using ClonalFrame revealed a formation of a distinct monophyletic lineage by these two CCs, suggesting a certain degree of clonality of the C. jejuni population adapted to barnacle geese. Therefore, although STs also commonly found in humans patients (e.g. ST-45) were among the barnacle geese C. jejuni isolates, this reservoir is probably an infrequent source for human campylobacteriosis. © 2014 Blackwell Verlag GmbH.

  11. Extraction and characterization of organic matter from surface waters (reservoir of Keddara in Algeria).

    Science.gov (United States)

    Aouabed, A; Ben Aim, R; Hadj-Boussaad, D E

    2001-05-01

    The combined XAD-8 and XAD-4 resin procedure for isolating dissolved organic solutes from Keddara reservoir in Algeria was found to isolate 65% of total organic carbon (TOC). Of the 45% of solute adsorbed onto XAD-8 resin, 34% was in the form of fulvic acids, and 11% humic acids. Approximately 19% of the hydrophilic solutes were adsorbed onto XAD-4 resin. Characterization experiments have shown that the three isolated fractions have a low apparent molecular weight investigated by ultrafiltration and fluorescence and low aromaticity as shown by the results of UV-absorbance, the formation potential of total organic halogens (reactivity with chlorine) and the polyhydroxyaromatic (PHA) determined by pyrolysis gas chromatography/mass spectrometry (GC/MS) which show that the isolated fractions are aliphatic as well as aromatic. The low molecular weight and the low aromaticity compared with literature data are due to coagulation and sedimentation of NOM with high molecular weight, which occur naturally in the reservoir. The Keddara reservoir, with low hydraulic loading area and long detention times receiving water with low NOM and high in hardness can be expected to be very effective coagulation and sedimentation basins.

  12. Modeling of Turbidity Variation in Two Reservoirs Connected by a Water Transfer Tunnel in South Korea

    Directory of Open Access Journals (Sweden)

    Jae Chung Park

    2017-06-01

    Full Text Available The Andong and Imha reservoirs in South Korea are connected by a water transfer tunnel. The turbidity of the Imha reservoir is much higher than that of the Andong reservoir. Thus, it is necessary to examine the movement of turbidity between the two reservoirs via the water transfer tunnel. The aim of this study was to investigate the effect of the water transfer tunnel on the turbidity behavior of the two connecting reservoirs and to further understand the effect of reservoir turbidity distribution as a function of the selective withdrawal depth. This study applied the CE-QUAL-W2, a water quality and 2-dimensional hydrodynamic model, for simulating the hydrodynamic processes of the two reservoirs. Results indicate that, in the Andong reservoir, the turbidity of the released water with the water transfer tunnel was similar to that without the tunnel. However, in the Imha reservoir, the turbidity of the released water with the water transfer tunnel was lower than that without the tunnel. This can be attributed to the higher capacity of the Andong reservoir, which has double the storage of the Imha reservoir. Withdrawal turbidity in the Imha reservoir was investigated using the water transfer tunnel. This study applied three withdrawal selections as elevation (EL. 141.0 m, 146.5 m, and 152.0 m. The highest withdrawal turbidity resulted in EL. 141.0 m, which indicates that the high turbidity current is located at a vertical depth of about 20–30 m because of the density difference. These results will be helpful for understanding the release and selective withdrawal turbidity behaviors for a water transfer tunnel between two reservoirs.

  13. Reservoir Characterization of Bridgeport and Cypress Sandstones in Lawrence Field Illinois to Improve Petroleum Recovery by Alkaline-Surfactant-Polymer Flood

    Energy Technology Data Exchange (ETDEWEB)

    Seyler, Beverly; Grube, John; Huff, Bryan; Webb, Nathan; Damico, James; Blakley, Curt; Madhavan, Vineeth; Johanek, Philip; Frailey, Scott

    2012-12-21

    Within the Illinois Basin, most of the oilfields are mature and have been extensively waterflooded with water cuts that range up to 99% in many of the larger fields. In order to maximize production of significant remaining mobile oil from these fields, new recovery techniques need to be researched and applied. The purpose of this project was to conduct reservoir characterization studies supporting Alkaline-Surfactant-Polymer Floods in two distinct sandstone reservoirs in Lawrence Field, Lawrence County, Illinois. A project using alkaline-surfactantpolymer (ASP) has been established in the century old Lawrence Field in southeastern Illinois where original oil in place (OOIP) is estimated at over a billion barrels and 400 million barrels have been recovered leaving more than 600 million barrels as an EOR target. Radial core flood analysis using core from the field demonstrated recoveries greater than 20% of OOIP. While the lab results are likely optimistic to actual field performance, the ASP tests indicate that substantial reserves could be recovered even if the field results are 5 to 10% of OOIP. Reservoir characterization is a key factor in the success of any EOR application. Reservoirs within the Illinois Basin are frequently characterized as being highly compartmentalized resulting in multiple flow unit configurations. The research conducted on Lawrence Field focused on characteristics that define reservoir compartmentalization in order to delineate preferred target areas so that the chemical flood can be designed and implemented for the greatest recovery potential. Along with traditional facies mapping, core analyses and petrographic analyses, conceptual geological models were constructed and used to develop 3D geocellular models, a valuable tool for visualizing reservoir architecture and also a prerequisite for reservoir simulation modeling. Cores were described and potential permeability barriers were correlated using geophysical logs. Petrographic analyses

  14. Functional characterization of the antibiotic resistance reservoir in the human microflora.

    Science.gov (United States)

    Sommer, Morten O A; Dantas, Gautam; Church, George M

    2009-08-28

    To understand the process by which antibiotic resistance genes are acquired by human pathogens, we functionally characterized the resistance reservoir in the microbial flora of healthy individuals. Most of the resistance genes we identified using culture-independent sampling have not been previously identified and are evolutionarily distant from known resistance genes. By contrast, nearly half of the resistance genes we identified in cultured aerobic gut isolates (a small subset of the gut microbiome) are identical to resistance genes harbored by major pathogens. The immense diversity of resistance genes in the human microbiome could contribute to future emergence of antibiotic resistance in human pathogens.

  15. Numerical modeling of shear stimulation in naturally fractured geothermal reservoirs

    OpenAIRE

    Ucar, Eren

    2018-01-01

    Shear-dilation-based hydraulic stimulations are conducted to create enhanced geothermal systems (EGS) from low permeable geothermal reservoirs, which are initially not amenable to energy production. Reservoir stimulations are done by injecting low-pressurized fluid into the naturally fractured formations. The injection aims to activate critically stressed fractures by decreasing frictional strength and ultimately cause a shear failure. The shear failure leads to a permanent ...

  16. A METHODOLOGY TO INTEGRATE MAGNETIC RESONANCE AND ACOUSTIC MEASUREMENTS FOR RESERVOIR CHARACTERIZATION

    Energy Technology Data Exchange (ETDEWEB)

    Jorge O. Parra; Chris L. Hackert; Lorna L. Wilson

    2002-09-20

    The work reported herein represents the third year of development efforts on a methodology to interpret magnetic resonance and acoustic measurements for reservoir characterization. In this last phase of the project we characterize a vuggy carbonate aquifer in the Hillsboro Basin, Palm Beach County, South Florida, using two data sets--the first generated by velocity tomography and the second generated by reflection tomography. First, we integrate optical macroscopic (OM), scanning electron microscope (SEM) and x-ray computed tomography (CT) images, as well as petrography, as a first step in characterizing the aquifer pore system. This pore scale integration provides information with which to evaluate nuclear magnetic resonance (NMR) well log signatures for NMR well log calibration, interpret ultrasonic data, and characterize flow units at the field scale between two wells in the aquifer. Saturated and desaturated NMR core measurements estimate the irreducible water in the rock and the variable T{sub 2} cut-offs for the NMR well log calibration. These measurements establish empirical equations to extract permeability from NMR well logs. Velocity and NMR-derived permeability and porosity relationships integrated with velocity tomography (based on crosswell seismic measurements recorded between two wells 100 m apart) capture two flow units that are supported with pore scale integration results. Next, we establish a more detailed picture of the complex aquifer pore structures and the critical role they play in water movement, which aids in our ability to characterize not only carbonate aquifers, but reservoirs in general. We analyze petrography and cores to reveal relationships between the rock physical properties that control the compressional and shear wave velocities of the formation. A digital thin section analysis provides the pore size distributions of the rock matrix, which allows us to relate pore structure to permeability and to characterize flow units at the

  17. Field Demonstration of Horizontal Infill Drilling Using Cost-effective Integrated Reservoir Modeling--Mississippian Carbonates, Central Kansas

    Energy Technology Data Exchange (ETDEWEB)

    Saibal Bhattacharya

    2005-08-31

    data constraints afflicting mature Mississippian fields. A publicly accessible databank of representative petrophysical properties and relationships was developed to overcome the paucity of such data that is critical to modeling the storage and flow in these reservoirs. Studies in 3 Mississippian fields demonstrated that traditional reservoir models built by integrating log, core, DST, and production data from existing wells on 40-acre spacings are unable to delineate karst-induced compartments, thus making 3D-seismic data critical to characterize these fields. Special attribute analyses on 3D data were shown to delineate reservoir compartments and predict those with pay porosities. Further testing of these techniques is required to validate their applicability in other Mississippian reservoirs. This study shows that detailed reservoir characterization and simulation on geomodels developed by integrating wireline log, core, petrophysical, production and pressure, and 3D-seismic data enables better evaluation of a candidate field for horizontal infill applications. In addition to reservoir compartmentalization, two factors were found to control the economic viability of a horizontal infill well in a mature Mississippian field: (a) adequate reservoir pressure support, and (b) an average well spacing greater than 40-acres.

  18. Model Studies on the Effectiveness of MBBR Reactors for the Restoration of Small Water Reservoirs

    Science.gov (United States)

    Nowak, Agata; Mazur, Robert; Panek, Ewa; Chmist, Joanna

    2018-02-01

    The authors present the Moving Bed Biofilm Reactor (MBBR) model with a quasi-continuous flow for small water reservoir restoration, characterized by high concentrations of organic pollutants. To determine the efficiency of wastewater treatment the laboratory analysis of physic-chemical parameters were conducted for the model on a semi-technical scale of 1:3. Wastewater treatment process was carried out in 24 h for 1 m3 for raw sewage. The startup period was 2 weeks for all biofilters (biological beds). Approximately 50% reduction in COD and BOD5 was obtained on average for the studied bioreactors. Significant improvements were achieved in theclarity of the treated wastewater, with the reduction of suspension by 60%. The oxygen profile has improved significantly in 7 to 9 hours of the process, and a diametric reduction in the oxidative reduction potential was recorded. A preliminary model of biological treatment effectiveness was determined based on the conducted studies. In final stages, the operation mode was set in real conditions of polluted water reservoirs.

  19. Reservoir characterization and performance predictions for the E.N. Woods lease

    Energy Technology Data Exchange (ETDEWEB)

    Aka-Milan, Francis A.

    2000-07-07

    The task of this work was to evaluate the past performance of the E.N. WOODS Unit and to forecast its future economic performance by taking into consideration the geology, petrophysics and production history of the reservoir. The Decline Curve Analysis feature of the Appraisal of Petroleum Properties including Taxation Systems (EDAPT) software along with the Production Management Systems (PMS) software were used to evaluate the original volume of hydrocarbon in place and estimate the reserve. The Black Oil Simulator (BOAST II) was then used to model the waterflooding operation and estimate the incremental oil production attributable to the water injection. BOAST II was also used to predict future performance of the reservoir.

  20. Surface Reservoir Characterization and Stratigraphic Studies Using Rock Magnetism and EPR in Venezuela: A Review

    Science.gov (United States)

    Aldana, M.; Diaz, M.; Costanzo-Alvarez, V.

    2007-05-01

    During the last years, the Paleomagnetic and Rock Magnetic Laboratory at the Simon Bolivar University has incorporated studies of rock magnetism and non conventional techniques in geophysics (as Electronic Paramagnetic Resonance or EPR) to solve diverse problems at the Venezuelan oil industry. Particularly, surface reservoir characterization and EPR-Magnetostratigraphic studies have been performed. At some Venezuelan oil fields (Guafita, La Victoria and Furrial) rock magnetic properties studies (e.g. Magnetic Susceptibility (MS)), extractable organic matter (EOM) and organic matter free radical concentration (OMFRC obtained via EPR) analysis have been applied trying to identified, at shallow levels, the "oil magnetic signature" of subjacent reservoirs. The results obtained in non consolidated samples from the first 1500 m of producers and non producers wells, show the existence of MS, EOM and OMFRC anomalies at shallow levels that are associated with an underlying reservoir and/or oil migration. Authigenic spherical aggregates of submicronic FE-rich magnetic crystals, observed by Scanning Electron Microscopy (SEM), are responsible for the detected MS anomalies. These studies allowed to establish a set of criteria (i.e. EPR, EOM and SEM) in order to link, with a minimum uncertainty, near-surface MS anomalies with the underlying reservoir. We have also explored the application of EPR, combined with petrographic, MS analysis, Qn and S-ratios, to characterize stratigraphic facies and identifying depositional environments at various sections in southwestern Venezuela. The different paramagnetic species that have been identified (e.g. manganese, free radicals and different Fe forms) together with the rock magnetic parameters, seem to give valuable information regarding the lithological characteristics of the studied sections. According to our results, as manganese content is related with the redox conditions, it can be used as a paleoenvironmental change index in

  1. Advanced Reservoir Characterization and Evaluation of CO2 Gravity Drainage in the Naturally Fractured Spraberry Trend Area, Class III

    Energy Technology Data Exchange (ETDEWEB)

    Knight, Bill; Schechter, David S.

    2002-07-26

    The goal of this project was to assess the economic feasibility of CO2 flooding the naturally fractured Spraberry Trend Area in west Texas. This objective was accomplished through research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interactions in the reservoirs, (3) reservoir performance analysis, and (4) experimental investigations on CO2 gravity drainage in Spraberry whole cores. This provides results of the final year of the six-year project for each of the four areas.

  2. Advanced Reservoir Characterization and Evaluation of CO{sub 2} Gravity Drainage in the Naturally Fractured Spraberry Trend Area

    Energy Technology Data Exchange (ETDEWEB)

    Schechter, D.S.

    1999-02-03

    The overall goal of this project is to assess the economic feasibility of CO{sub 2} flooding the naturally fractured Spraberry Trend Area in West Texas. This objective is being accomplished by conducting research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interactions in the reservoirs, (3) reservoir performance analysis, and, (4) experimental investigations on CO2 gravity drainage in Spraberry whole cores. This report provides results of the third year of the five-year project for each of the four areas including a status report of field activities leading up to injection of CO2.

  3. Increasing Heavy Oil Reserves in the Wilmington Oil Field Through Advanced Reservoir Characterization and Thermal Production Technologies, Class III

    Energy Technology Data Exchange (ETDEWEB)

    City of Long Beach; Tidelands Oil Production Company; University of Southern California; David K. Davies and Associates

    2002-09-30

    The objective of this project was to increase the recoverable heavy oil reserves within sections of the Wilmington Oil Field, near Long Beach, California through the testing and application of advanced reservoir characterization and thermal production technologies. It was hoped that the successful application of these technologies would result in their implementation throughout the Wilmington Field and, through technology transfer, will be extended to increase the recoverable oil reserves in other slope and basin clastic (SBC) reservoirs.

  4. Simulation of Gas Transport in Tight/Shale Gas Reservoirs by a Multicomponent Model Based on PEBI Grid

    OpenAIRE

    Zhang, Longjun; Li, Daolun; Wang, Lei; Lu, Detang

    2015-01-01

    The ultra-low permeability and nanosize pores of tight/shale gas reservoir would lead to non-Darcy flow including slip flow, transition flow, and free molecular flow, which cannot be described by traditional Darcy’s law. The organic content often adsorbs some gas content, while the adsorbed amount for different gas species is different. Based on these facts, we develop a new compositional model based on unstructured PEBI (perpendicular bisection) grid, which is able to characterize non-Darcy ...

  5. Structural characterization of rhamnolipid produced by Pseudomonas aeruginosa strain FIN2 isolated from oil reservoir water.

    Science.gov (United States)

    Liu, Jin-Feng; Wu, Gang; Yang, Shi-Zhong; Mu, Bo-Zhong

    2014-05-01

    Biosurfactant-producing microorganisms inhabiting oil reservoirs are of great potential in industrial applications. Yet, till now, the knowledge about the structure and physicochemical property of their metabolites are still limited. The aim of this study was to purify and structurally characterize the biosurfactant from Pseudomonas aeruginosa strain FIN2, a newly isolated strain from an oil reservoir. The purification was conducted by silica gel column chromatography followed by pre-RP HPLC and the structural characterization was carried out by GC-MS combined with MS/MS. The results show that the biosurfactant produced by FIN2 is rhamnolipid in nature and its four main fractions were identified to be Rha-C10-C10(46.1 %), Rha-Rha-C10-C10(20.1 %), Rha-C8-C10 (7.5 %) and Rha-C10-C12:1(5.5 %), respectively. Meanwhile, the rarely reported rhamnolipid congeners containing β-hydroxy fatty acids of C6, C9, C10:1 and C11 were also proved to be present in the rhamnolipid mixture produced. The rhamnolipid mixture exhibited a strong surface activity by lowering the surface tension of distilled water to 28.6 mN/m with a CMC value of 195 mg/l.

  6. Statistical analysis of surface lineaments and fractures for characterizing naturally fractured reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Genliang; George, S.A.; Lindsey, R.P.

    1997-08-01

    Thirty-six sets of surface lineaments and fractures mapped from satellite images and/or aerial photos from parts of the Mid-continent and Colorado Plateau regions were collected, digitized, and statistically analyzed in order to obtain the probability distribution functions of natural fractures for characterizing naturally fractured reservoirs. The orientations and lengths of the surface linear features were calculated using the digitized coordinates of the two end points of each individual linear feature. The spacing data of the surface linear features within an individual set were, obtained using a new analytical sampling technique. Statistical analyses were then performed to find the best-fit probability distribution functions for the orientation, length, and spacing of each data set. Twenty-five hypothesized probability distribution functions were used to fit each data set. A chi-square goodness-of-fit test was used to rank the significance of each fit. A distribution which provides the lowest chi-square goodness-of-fit value was considered the best-fit distribution. The orientations of surface linear features were best-fitted by triangular, normal, or logistic distributions; the lengths were best-fitted by PearsonVI, PearsonV, lognormal2, or extreme-value distributions; and the spacing data were best-fitted by lognormal2, PearsonVI, or lognormal distributions. These probability functions can be used to stochastically characterize naturally fractured reservoirs.

  7. Modeling flow in nanoporous, membrane reservoirs and interpretation of coupled fluxes

    Science.gov (United States)

    Geren, Filiz

    The average pore size in unconventional, tight-oil reservoirs is estimated to be less than 100 nm. At this pore size, Darcy flow is no longer the dominating flow mechanism and a combination of diffusive flows determines the flow characteristics. Concentration driven self-diffusion has been well known and included in the flow and transport models in porous media. However, when the sizes of the pores and pore-throats decrease down to the size of the hydrocarbon molecules, the porous medium acts like a semi-permeable membrane, and the size of the pore openings dictates the direction of transport between adjacent pores. Accordingly, characterization of flow and transport in tight unconventional plays requires understanding of their membrane properties. This Master of Science thesis first highlights the membrane properties of nanoporous, unconventional reservoirs and then discusses how filtration effects can be incorporated into the models of transport in nanoporous media within the coupled flux concept. The effect of filtration on fluid composition and its impact on black-oil fluid properties like bubble point pressure is also demonstrated. To define filtration and filtration pressure in unconventional, tight-oil reservoirs, analogy to chemical osmosis is applied two pore systems connected with a pore throat, which shows membrane properties. Because the pore throat selectivity permits the passage of fluid molecules by their sizes, given a filtration pressure difference between the two pore systems, the concentration difference between the systems is determined by flash calculations. The results are expressed in the form of filtration (membrane) efficiency, which is essential parameter to define coupled fluxes for porous media flow.

  8. Integrating a reservoir regulation scheme into a spatially distributed hydrological model

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Gang; Gao, Huilin; Naz, Bibi S.; Kao, Shih-Chieh; Voisin, Nathalie

    2016-12-01

    During the past several decades, numerous reservoirs have been built across the world for a variety of purposes such as flood control, irrigation, municipal/industrial water supplies, and hydropower generation. Consequently, natural streamflow timing and magnitude have been altered significantly by reservoir operations. In addition, the hydrological cycle can be modified by land use/land cover and climate changes. To understand the fine scale feedback between hydrological processes and water management decisions, a distributed hydrological model embedded with a reservoir component is of desire. In this study, a multi-purpose reservoir module with predefined complex operational rules was integrated into the Distributed Hydrology Soil Vegetation Model (DHSVM). Conditional operating rules, which are designed to reduce flood risk and enhance water supply reliability, were adopted in this module. The performance of the integrated model was tested over the upper Brazos River Basin in Texas, where two U.S. Army Corps of Engineers reservoirs, Lake Whitney and Aquilla Lake, are located. The integrated DHSVM model was calibrated and validated using observed reservoir inflow, outflow, and storage data. The error statistics were summarized for both reservoirs on a daily, weekly, and monthly basis. Using the weekly reservoir storage for Lake Whitney as an example, the coefficients of determination (R2) and the Nash-Sutcliff Efficiency (NSE) are 0.85 and 0.75, respectively. These results suggest that this reservoir module has promise for use in sub-monthly hydrological simulations. Enabled with the new reservoir component, the DHSVM model provides a platform to support adaptive water resources management under the impacts of evolving anthropogenic activities and substantial environmental changes.

  9. Modeling the hydrological behavior of a karst spring using a nonlinear reservoir-pipe model

    Science.gov (United States)

    Chang, Yong; Wu, Jichun; Jiang, Guanghui

    2015-08-01

    Karst aquifers are commonly simulated based on conceptual models. However, most karst conceptual models hardly consider the function of turbulent conduits. The conduit network acts as the main draining passage of the karst aquifer and may also have a strong influence on the hydrological processes, especially during storm events. A conceptual model with a nonlinear reservoir and a turbulent pipe (representing the conduit system) in series is proposed according to the basic structure of a typical karst aquifer, to simulate the karst spring. The model indicates whether the spring discharge is influenced by the turbulent pipe; this not only depends on the parameters of the nonlinear reservoir and turbulent pipe, but also depends on the volume of spring discharge itself. Even though the spring discharge is strongly influenced by the turbulent pipe during the storm, this influence decreases with the rainfall intensity and volume of spring discharge. In addition, an `evapotranspiration store' is used to consider the moisture loss through evapotranspiration and to calculate the effective rainfall on the proposed model. Then, this simple conceptual model is used to simulate a karst spring (named S31) near Guilin city, China, with satisfactory results, especially with respect to discharge peaks and recession curves of the spring under storm conditions. The proposed model is also compared with the Vensim model of similar complexity, which has been applied to the same spring catchment. The comparison shows the superiority and better performance of the nonlinear reservoir-pipe model.

  10. Application of advanced reservoir characterization, simulation, and production optimization strategies to maximize recovery in slope and basin clastic reservoirs, West Texas (Delaware Basin). Quarterly report, October 1 - December 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, S.P.

    1997-01-01

    The objective of this project is to demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost effective way to recover a higher percentage of the original oil in place through strategic placement of infill wells and geologically based field development. Project objectives are divided into two major phases. The objectives of the reservoir characterization phase of the project are to provide a detailed understanding of the architecture and heterogeneity of two fields, the Ford Geraldine unit and Ford West field, which produce from the Bell Canyon and Cherry Canyon Formations, respectively, of the Delaware Mountain Group and to compare Bell Canyon and Cherry Canyon reservoirs. Reservoir characterization will utilize 3-D seismic data, high-resolution sequence stratigraphy, subsurface field studies, outcrop characterization, and other techniques. Once the reservoir-characterization study of both fields is completed, a pilot area of approximately 1 mi{sup 2} in one of the fields will be chosen for reservoir simulation. The objectives of the implementation phase of the project are to (1) apply the knowledge gained from reservoir characterization and simulation studies to increase recovery from the pilot area, (2) demonstrate that economically significant unrecovered oil remains in geologically resolvable untapped compartments, and (3) test the accuracy of reservoir characterization and flow simulation as predictive tools in resource preservation of mature fields. A geologically designed, enhanced-recovery program (CO{sub 2} flood, waterflood, or polymer flood) and well-completion program will be developed, and one to three infill wells will be drilled and cored. Technical progress is summarized for: geophysical characterization; reservoir characterization; outcrop characterization; and recovery technology identification and analysis.

  11. Determination of heterogeneity by high-resolution seismic reservoir characterization in the heavy oil Temblor reservoir of Coalinga Field, California

    Science.gov (United States)

    Mahapatra, Sailendra Nath

    The research focuses on analysis and subsurface imaging of siliciclastics rocks on steam-affected 3D poststack seismic data, merged from different vintages, from the Temblor Formation in the Coalinga heavy oil reservoir in the San Joaquin basin, California. The objective was identification, delineation, and demarcation of reservoir heterogeneities by seismostratigraphic and seismogeomorphic analysis. The proximity of the San Andreas Transforms greatly controlled basin evolution and caused substantial reservoir heterogeneity by changing the depositional environment from shallow marine to near-shore fluvial. Moreover, two unconformities dissect the reservoir interval. The seismic dataset exhibits erratic, distorted reflection strengths and amplitudes caused by steam-injection-aided production. A petrophysical analysis based on Gassmann fluid substitution suggests a 27% P-wave velocity decrease in steam-saturated intervals. Seismic to well log ties were problematic and vexing due to the resulting statics, wavelet changes, and line mismatches. Mapping and flattening on a deeper horizon, however, allowed mapping of the internal unconformities and well ties which were crucial for seismostratigraphic sequence identification. Visualization of seismic attributes brought out stratification patterns and two distinct, laterally and vertically extensive, porous, and interconnected facies tracts interpreted as incised valley fills and tidal-to-subtidal deposits as evidenced by bright, steam related amplitudes. Seismic attribute analysis, Geobody Visualization and Interpretation, and structure and isochron maps brought out two prominent channel-systems, recut and restacked in the central part of the area. These deposits were identified on seismic data and correlated to high-gamma coarsening-upward sands on logs and cores. The deeper one, shifting towards SSE with depth, lies between the Base Temblor and Buttonbed unconformities both in the southwestern and northwestern parts of

  12. Depositional sequence analysis and sedimentologic modeling for improved prediction of Pennsylvanian reservoirs (Annex 1). Annual report, February 1, 1991--January 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Watney, W.L.

    1992-08-01

    Interdisciplinary studies of the Upper Pennsylvanian Lansing and Kansas City groups have been undertaken in order to improve the geologic characterization of petroleum reservoirs and to develop a quantitative understanding of the processes responsible for formation of associated depositional sequences. To this end, concepts and methods of sequence stratigraphy are being used to define and interpret the three-dimensional depositional framework of the Kansas City Group. The investigation includes characterization of reservoir rocks in oil fields in western Kansas, description of analog equivalents in near-surface and surface sites in southeastern Kansas, and construction of regional structural and stratigraphic framework to link the site specific studies. Geologic inverse and simulation models are being developed to integrate quantitative estimates of controls on sedimentation to produce reconstructions of reservoir-bearing strata in an attempt to enhance our ability to predict reservoir characteristics.

  13. Physical property characterization of a damage zone in granitic rock - Implications for geothermal reservoir properties

    Science.gov (United States)

    Wenning, Quinn; Madonna, Claudio; Amann, Florian; Gischig, Valentin; Burg, Jean-Pierre

    2016-04-01

    Geothermal energy offers a viable alternative to mitigate greenhouse gas emitting energy production. A tradeoff between less expensive drilling costs and increased permeability at shallow depths versus increased heat production at deeper depths stipulates the economic energy potential of a given reservoir. From a geological perspective, successful retrieval of geothermal energy from the subsurface requires sufficient knowledge of the structural and stratigraphic relationship of the target formations, which govern the thermal conditions, physical properties, and fluid flow properties of reservoir rocks. In Switzerland, deep basement rocks (~5 km) with fluid conducting damage zones and enhanced fractured systems stimulated by hydraulic shearing are seen as a potential geothermal reservoir system. Damage zones, both natural and induced, provide permeability enhancement that is especially important for creating fluid conductivity where the matrix permeability is low. This study concentrates on characterizing the elastic and transport properties entering into a natural damage zone penetrated by a borehole at the Grimsel underground research laboratory. The borehole drilled from a cavern at 480 m below ground surface penetrates approximately 20 m of mostly intact Grimsel granodiorite before entering the first phyllosilicate-rich shear zone (~0.2 m thick). The borehole intersects a second shear zone at approximately 23.8m. Between the two shear zones the Grimsel granodiorite is heavily fractured. The minimum principle stress magnitude from in-situ measurements decreases along the borehole into the first shear zone. Two mutually perpendicular core samples of Grimsel granodiorite were taken every 0.1 m from 19.5 to 20.1 m to characterize the physical properties and anisotropy changes as a gradient away from the damage zone. Measurements of ultrasonic compressional (Vp) and shear (Vs) velocities at 1 MHz frequency are conducted at room temperature and hydrostatic pressures

  14. Development of infill drilling recovery models for carbonates reservoirs using neural networks and multivariate statistical as a novel method

    International Nuclear Information System (INIS)

    Soto, R; Wu, Ch. H; Bubela, A M

    1999-01-01

    This work introduces a novel methodology to improve reservoir characterization models. In this methodology we integrated multivariate statistical analyses, and neural network models for forecasting the infill drilling ultimate oil recovery from reservoirs in San Andres and Clearfork carbonate formations in west Texas. Development of the oil recovery forecast models help us to understand the relative importance of dominant reservoir characteristics and operational variables, reproduce recoveries for units included in the database, forecast recoveries for possible new units in similar geological setting, and make operational (infill drilling) decisions. The variety of applications demands the creation of multiple recovery forecast models. We have developed intelligent software (Soto, 1998), oilfield intelligence (01), as an engineering tool to improve the characterization of oil and gas reservoirs. 01 integrates neural networks and multivariate statistical analysis. It is composed of five main subsystems: data input, preprocessing, architecture design, graphic design, and inference engine modules. One of the challenges in this research was to identify the dominant and the optimum number of independent variables. The variables include porosity, permeability, water saturation, depth, area, net thickness, gross thickness, formation volume factor, pressure, viscosity, API gravity, number of wells in initial water flooding, number of wells for primary recovery, number of infill wells over the initial water flooding, PRUR, IWUR, and IDUR. Multivariate principal component analysis is used to identify the dominant and the optimum number of independent variables. We compared the results from neural network models with the non-parametric approach. The advantage of the non-parametric regression is that it is easy to use. The disadvantage is that it retains a large variance of forecast results for a particular data set. We also used neural network concepts to develop recovery

  15. Multi-scale reservoir modeling as an integrated assessment tool for geo-sequestration in the San Juan Basin

    Science.gov (United States)

    Young, G.; Haerer, D.; Bromhal, G.; Reeves, S.

    2007-01-01

    The Southwestern Regional Partnership on CO2 Sequestration conducted an Enhanced Coalbed Methane (ECBM)/Carbon Storage Pilot in the San Juan Basin as part of the ongoing DOE/NETL Carbon Capture and Storage Program. The primary goal of this pilot is to demonstrate the efficacy of using CO2 to enhance coalbed methane recovery particularly near reservoir abandonment pressure while also evaluating the suitability of coal seams for longer-term carbon storage. Basic geologic models of the coal seams were developed from well logs in the area. Production histories from several surrounding CBM wells were shown. To monitor the injection of up to 75,000 ton of CO2 beginning September 2007, seismic surveys and tiltmeter arrays were utilized. Larger-scale geo-hydrodynamic simulations were used to develop a regional model for the fluid dynamics of the northern San Juan Basin. Smaller-scale reservoir simulations, incorporating available laboratory and field data, were used to develop an improved understanding of reservoir dynamics within the specific 640-acre pilot area. Both modeling scales were critical to assessing the suitability of deploying commercial carbon storage programs throughout the basin. Reservoir characterization results on the optimization of total CO2 injection volume, injection rate over time, and how CO2 is expected to disperse after injection are presented. This is an abstract of a paper presented at the 2007 AIChE Annual Meeting (Salt Lake City, UT 11/4-9/2007).

  16. Amplitude various angles (AVA) phenomena in thin layer reservoir: Case study of various reservoirs

    International Nuclear Information System (INIS)

    thfloor, Physics Dept., FMIPA, Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Bandung (Indonesia))" data-affiliation=" (Wave Inversion and Subsurface Fluid Imaging Research Laboratory (WISFIR), Basic Science Center A 4thfloor, Physics Dept., FMIPA, Institut Teknologi Bandung (Indonesia); Rock Fluid Imaging Lab., Bandung (Indonesia))" >Nurhandoko, Bagus Endar B.; Susilowati

    2015-01-01

    Amplitude various offset is widely used in petroleum exploration as well as in petroleum development field. Generally, phenomenon of amplitude in various angles assumes reservoir’s layer is quite thick. It also means that the wave is assumed as a very high frequency. But, in natural condition, the seismic wave is band limited and has quite low frequency. Therefore, topic about amplitude various angles in thin layer reservoir as well as low frequency assumption is important to be considered. Thin layer reservoir means the thickness of reservoir is about or less than quarter of wavelength. In this paper, I studied about the reflection phenomena in elastic wave which considering interference from thin layer reservoir and transmission wave. I applied Zoeppritz equation for modeling reflected wave of top reservoir, reflected wave of bottom reservoir, and also transmission elastic wave of reservoir. Results show that the phenomena of AVA in thin layer reservoir are frequency dependent. Thin layer reservoir causes interference between reflected wave of top reservoir and reflected wave of bottom reservoir. These phenomena are frequently neglected, however, in real practices. Even though, the impact of inattention in interference phenomena caused by thin layer in AVA may cause inaccurate reservoir characterization. The relation between classes of AVA reservoir and reservoir’s character are different when effect of ones in thin reservoir and ones in thick reservoir are compared. In this paper, I present some AVA phenomena including its cross plot in various thin reservoir types based on some rock physics data of Indonesia

  17. Review on applications of artificial intelligence methods for dam and reservoir-hydro-environment models.

    Science.gov (United States)

    Allawi, Mohammed Falah; Jaafar, Othman; Mohamad Hamzah, Firdaus; Abdullah, Sharifah Mastura Syed; El-Shafie, Ahmed

    2018-04-03

    Efficacious operation for dam and reservoir system could guarantee not only a defenselessness policy against natural hazard but also identify rule to meet the water demand. Successful operation of dam and reservoir systems to ensure optimal use of water resources could be unattainable without accurate and reliable simulation models. According to the highly stochastic nature of hydrologic parameters, developing accurate predictive model that efficiently mimic such a complex pattern is an increasing domain of research. During the last two decades, artificial intelligence (AI) techniques have been significantly utilized for attaining a robust modeling to handle different stochastic hydrological parameters. AI techniques have also shown considerable progress in finding optimal rules for reservoir operation. This review research explores the history of developing AI in reservoir inflow forecasting and prediction of evaporation from a reservoir as the major components of the reservoir simulation. In addition, critical assessment of the advantages and disadvantages of integrated AI simulation methods with optimization methods has been reported. Future research on the potential of utilizing new innovative methods based AI techniques for reservoir simulation and optimization models have also been discussed. Finally, proposal for the new mathematical procedure to accomplish the realistic evaluation of the whole optimization model performance (reliability, resilience, and vulnerability indices) has been recommended.

  18. Molecular Simulation towards Efficient and Representative Subsurface Reservoirs Modeling

    KAUST Repository

    Kadoura, Ahmad

    2016-09-01

    This dissertation focuses on the application of Monte Carlo (MC) molecular simulation and Molecular Dynamics (MD) in modeling thermodynamics and flow of subsurface reservoir fluids. At first, MC molecular simulation is proposed as a promising method to replace correlations and equations of state in subsurface flow simulators. In order to accelerate MC simulations, a set of early rejection schemes (conservative, hybrid, and non-conservative) in addition to extrapolation methods through reweighting and reconstruction of pre-generated MC Markov chains were developed. Furthermore, an extensive study was conducted to investigate sorption and transport processes of methane, carbon dioxide, water, and their mixtures in the inorganic part of shale using both MC and MD simulations. These simulations covered a wide range of thermodynamic conditions, pore sizes, and fluid compositions shedding light on several interesting findings. For example, the possibility to have more carbon dioxide adsorbed with more preadsorbed water concentrations at relatively large basal spaces. The dissertation is divided into four chapters. The first chapter corresponds to the introductory part where a brief background about molecular simulation and motivations are given. The second chapter is devoted to discuss the theoretical aspects and methodology of the proposed MC speeding up techniques in addition to the corresponding results leading to the successful multi-scale simulation of the compressible single-phase flow scenario. In chapter 3, the results regarding our extensive study on shale gas at laboratory conditions are reported. At the fourth and last chapter, we end the dissertation with few concluding remarks highlighting the key findings and summarizing the future directions.

  19. Modeling of Salinity Effects on Waterflooding of Petroleum Reservoirs

    OpenAIRE

    Alexeev, Artem; Shapiro, Alexander; Thomsen, Kaj

    2015-01-01

    ”Smart water flooding” er en forbedret olieindvindings (EOR) teknik, der er baseret på injektion af vand med kemisk optimeret saltindhold i olie reservoirer. Omfattende forskning, der er udført i løbet af de seneste to årtier har tydeligt vist, at smart water flooding kan forbedre den ultimative olieindvindingsgrad både i carbonat- og i sandstens- reservoirer. Der er blevet foreslået en række forskellige fysisk-kemiske mekanismer til at forklare smart water effekten, men ingen af dem har være...

  20. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin)

    Energy Technology Data Exchange (ETDEWEB)

    Andrew G. Cole; George B. Asquith; Jose I. Guzman; Mark D. Barton; Mohammad A. Malik; Shirley P. Dutton; Sigrid J. Clift

    1998-04-01

    The objective of this Class III project is to demonstrate that detailed reservoir characterization of clastic reservoirs in basinal sandstones of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost-effective way to recover more of the original oil in place by strategic infill-well placement and geologically based enhanced oil recovery. The study focused on the Ford Geraldine unit, which produces from the upper Bell Canyon Formation (Ramsey sandstone). Reservoirs in this and other Delaware Mountain Group fields have low producibility (average recovery <14 percent of the original oil in place) because of a high degree of vertical and lateral heterogeneity caused by depositional processes and post-depositional diagenetic modification. Outcrop analogs were studied to better interpret the depositional processes that formed the reservoirs at the Ford Geraldine unit and to determine the dimensions of reservoir sandstone bodies. Facies relationships and bedding architecture within a single genetic unit exposed in outcrop in Culberson County, Texas, suggest that the sandstones were deposited in a system of channels and levees with attached lobes that initially prograded basinward, aggraded, and then turned around and stepped back toward the shelf. Channel sandstones are 10 to 60 ft thick and 300 to 3,000 ft wide. The flanking levees have a wedge-shaped geometry and are composed of interbedded sandstone and siltstone; thickness varies from 3 to 20 ft and length from several hundred to several thousands of feet. The lobe sandstones are broad lens-shaped bodies; thicknesses range up to 30 ft with aspect ratios (width/thickness) of 100 to 10,000. Lobe sandstones may be interstratified with laminated siltstones.

  1. Assessing spatial uncertainty in reservoir characterization for carbon sequestration planning using public well-log data: A case study

    Science.gov (United States)

    Venteris, E.R.; Carter, K.M.

    2009-01-01

    Mapping and characterization of potential geologic reservoirs are key components in planning carbon dioxide (CO2) injection projects. The geometry of target and confining layers is vital to ensure that the injected CO2 remains in a supercritical state and is confined to the target layer. Also, maps of injection volume (porosity) are necessary to estimate sequestration capacity at undrilled locations. Our study uses publicly filed geophysical logs and geostatistical modeling methods to investigate the reliability of spatial prediction for oil and gas plays in the Medina Group (sandstone and shale facies) in northwestern Pennsylvania. Specifically, the modeling focused on two targets: the Grimsby Formation and Whirlpool Sandstone. For each layer, thousands of data points were available to model structure and thickness but only hundreds were available to support volumetric modeling because of the rarity of density-porosity logs in the public records. Geostatistical analysis based on this data resulted in accurate structure models, less accurate isopach models, and inconsistent models of pore volume. Of the two layers studied, only the Whirlpool Sandstone data provided for a useful spatial model of pore volume. Where reliable models for spatial prediction are absent, the best predictor available for unsampled locations is the mean value of the data, and potential sequestration sites should be planned as close as possible to existing wells with volumetric data. ?? 2009. The American Association of Petroleum Geologists/Division of Environmental Geosciences. All rights reserved.

  2. 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.

  3. A systematic procedure for reservoir characterization: Annual report for the period October 1, 1985-September 30, 1986

    Energy Technology Data Exchange (ETDEWEB)

    Lake, L.W.; Kocurek, G.A.; Miller, M.A.

    1987-12-01

    This report deals with a variety of topics all centered around the main goal of making numerical reservoir simulation results conform more closely with geologic descriptions. The first part of the report discusses results on conditional simulations of miscible displacements in randomly heterogeneous permeable media. The focus here is on local or macroscopic dispersion, the dispersion experienced at a fixed point in the medium. Macroscopic dispersivity has many of the same dependencies on reservoir properties as does megascopic dispersivity, but it seems to be less time dependent and is always smaller. We have not discovered a mathematical model to describe its behavior. A major portion of the report deals with statistical descriptions. We investigate the bias and precision of standard measures of heterogeneity, the Lorenz and Dykstra-Parsons coefficient. After this, the work explores the benefits of using a distribution type characterization parameter in exploring heterogeneity. The final major protion of the report describes our mapping efforts on the Page sandstone outcrop in northern Arizona. The mapping is to be used in generating both deterministic descriptions and in calibrating the stochastic descriptions discussed above. 128 refs., 95 figs., 10 tabs.

  4. Application of Advanced Reservoir Characterization, Simulation, and Production Optimization Strategies to Maximize Recovery in Slope and Basin Clastic Reservoirs, West Texas (Delaware Basin), Class III

    Energy Technology Data Exchange (ETDEWEB)

    Dutton, Shirley P.; Flanders, William A.; Mendez, Daniel L.

    2001-05-08

    The objective of this Class 3 project was demonstrate that detailed reservoir characterization of slope and basin clastic reservoirs in sandstone's of the Delaware Mountain Group in the Delaware Basin of West Texas and New Mexico is a cost effective way to recover oil more economically through geologically based field development. This project was focused on East Ford field, a Delaware Mountain Group field that produced from the upper Bell Canyon Formation (Ramsey sandstone). The field, discovered in 9160, is operated by Oral Petco, Inc., as the East Ford unit. A CO2 flood was being conducted in the unit, and this flood is the Phase 2 demonstration for the project.

  5. 2-D Water Quality Modelling of a Drinking Water Reservoir

    Czech Academy of Sciences Publication Activity Database

    Růžička, Martin; Hejzlar, J.; Mikešová, P.; Cole, T. M.

    2002-01-01

    Roč. 50, č. 3 (2002), s. 258-272 ISSN 0042-790X R&D Projects: GA ČR GA103/98/0281; GA AV ČR IAA3042903 Grant - others:USARGD-UK(USA) N68171-99-M-6754 Keywords : CE-QUAL-W2 * Dimictic stratified reservoir * Sensitivity analysis Subject RIV: DA - Hydrology ; Limnology

  6. Modeling of Salinity Effects on Waterflooding of Petroleum Reservoirs

    DEFF Research Database (Denmark)

    Alexeev, Artem

    Smart Water flooding is an enhanced oil recovery (EOR) technique that is based on the injection of chemistry-optimized water with changed ionic composition and salinity into petroleum reservoirs. Extensive research that has been carried out over the past two decades has clearly demonstrated...

  7. Prediction of tectonic stresses and fracture networks with geomechanical reservoir models

    Energy Technology Data Exchange (ETDEWEB)

    Henk, A.; Fischer, K. [TU Darmstadt (Germany). Inst. fuer Angewandte Geowissenschaften

    2014-09-15

    This project evaluates the potential of geomechanical Finite Element (FE) models for the prediction of in situ stresses and fracture networks in faulted reservoirs. Modeling focuses on spatial variations of the in situ stress distribution resulting from faults and contrasts in mechanical rock properties. In a first methodological part, a workflow is developed for building such geomechanical reservoir models and calibrating them to field data. In the second part, this workflow was applied successfully to an intensively faulted gas reservoir in the North German Basin. A truly field-scale geomechanical model covering more than 400km{sup 2} was built and calibrated. It includes a mechanical stratigraphy as well as a network of 86 faults. The latter are implemented as distinct planes of weakness and allow the fault-specific evaluation of shear and normal stresses. A so-called static model describes the recent state of the reservoir and, thus, after calibration its results reveal the present-day in situ stress distribution. Further geodynamic modeling work considers the major stages in the tectonic history of the reservoir and provides insights in the paleo stress distribution. These results are compared to fracture data and hydraulic fault behavior observed today. The outcome of this project confirms the potential of geomechanical FE models for robust stress and fracture predictions. The workflow is generally applicable and can be used for modeling of any stress-sensitive reservoir.

  8. Prediction of tectonic stresses and fracture networks with geomechanical reservoir models

    International Nuclear Information System (INIS)

    Henk, A.; Fischer, K.

    2014-09-01

    This project evaluates the potential of geomechanical Finite Element (FE) models for the prediction of in situ stresses and fracture networks in faulted reservoirs. Modeling focuses on spatial variations of the in situ stress distribution resulting from faults and contrasts in mechanical rock properties. In a first methodological part, a workflow is developed for building such geomechanical reservoir models and calibrating them to field data. In the second part, this workflow was applied successfully to an intensively faulted gas reservoir in the North German Basin. A truly field-scale geomechanical model covering more than 400km 2 was built and calibrated. It includes a mechanical stratigraphy as well as a network of 86 faults. The latter are implemented as distinct planes of weakness and allow the fault-specific evaluation of shear and normal stresses. A so-called static model describes the recent state of the reservoir and, thus, after calibration its results reveal the present-day in situ stress distribution. Further geodynamic modeling work considers the major stages in the tectonic history of the reservoir and provides insights in the paleo stress distribution. These results are compared to fracture data and hydraulic fault behavior observed today. The outcome of this project confirms the potential of geomechanical FE models for robust stress and fracture predictions. The workflow is generally applicable and can be used for modeling of any stress-sensitive reservoir.

  9. A new approach to improve reservoir characterization using intelligent systems - a case study: Toldado field in Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Soto B, Rodolfo; Bernal, Maria C.; Silva, Bernardo; Bejarano, Aristobulo; Cobaleda, Gloria [Ecopetrol S.A., Bogota (Colombia)]|[Instituto Colombiano del Petroleo, Bogota (Colombia); Arango, Sandro; Torres, Freddy

    2000-07-01

    This paper presents a new technique to improve reservoir characterization. We integrated concepts of multivariate statistical analysis and soft computing to get better petrophysical models. We applied the proposed technique to model permeability for the highly heterogeneous cretaceous Caballos formation in Toldado field, Colombia. First, we evaluated the permeability model developed by D. K. Davies in this field. His method is based fundamentally on the identification of rock types (intervals of rock with unique pore geometry). We think this a good approach to improve the prediction of permeability. However, Davies gets traditional models (Log permeability vs. porosity) for each rock type. We found a 78% of average absolute error in his model for Toldado field. Using of multivariate statistical analysis, we found that the dominant independent variables to predict the permeability for Toldado field were porosity, index of the effective photo-electric absorption cross section of the formation, and gamma ray logs. Our neural network permeability model has an average absolute error less than 8%. Finally, we validated the neural network permeability model by applying the concept of the hydraulic interwell connectivity index (HICI). These models helped us to improve the history match and make recommendations to increase the oil production by about 500 bopd. (author)

  10. Simulation and optimisation modelling approach for operation of the Hoa Binh Reservoir, Vietnam

    DEFF Research Database (Denmark)

    Ngo, Long le; Madsen, Henrik; Rosbjerg, Dan

    2007-01-01

    . This paper proposes to optimise the control strategies for the Hoa Binh reservoir operation by applying a combination of simulation and optimisation models. The control strategies are set up in the MIKE 11 simulation model to guide the releases of the reservoir system according to the current storage level......, the hydro-meteorological conditions, and the time of the year. A heuristic global optimisation tool, the shuffled complex evolution (SCE) algorithm, is adopted for optimising the reservoir operation. The optimisation puts focus on the trade-off between flood control and hydropower generation for the Hoa...

  11. Modelling CO2 emissions from water surface of a boreal hydroelectric reservoir.

    Science.gov (United States)

    Wang, Weifeng; Roulet, Nigel T; Kim, Youngil; Strachan, Ian B; Del Giorgio, Paul; Prairie, Yves T; Tremblay, Alain

    2018-01-15

    To quantify CO 2 emissions from water surface of a reservoir that was shaped by flooding the boreal landscape, we developed a daily time-step reservoir biogeochemistry model. We calibrated the model using the measured concentrations of dissolved organic and inorganic carbon (C) in a young boreal hydroelectric reservoir, Eastmain-1 (EM-1), in northern Quebec, Canada. We validated the model against observed CO 2 fluxes from an eddy covariance tower in the middle of EM-1. The model predicted the variability of CO 2 emissions reasonably well compared to the observations (root mean square error: 0.4-1.3gCm -2 day -1 , revised Willmott index: 0.16-0.55). In particular, we demonstrated that the annual reservoir surface effluxes were initially high, steeply declined in the first three years, and then steadily decreased to ~115gCm -2 yr -1 with increasing reservoir age over the estimated "engineering" reservoir lifetime (i.e., 100years). Sensitivity analyses revealed that increasing air temperature stimulated CO 2 emissions by enhancing CO 2 production in the water column and sediment, and extending the duration of open water period over which emissions occur. Increasing the amount of terrestrial organic C flooded can enhance benthic CO 2 fluxes and CO 2 emissions from the reservoir water surface, but the effects were not significant over the simulation period. The model is useful for the understanding of the mechanism of C dynamics in reservoirs and could be used to assist the hydro-power industry and others interested in the role of boreal hydroelectric reservoirs as sources of greenhouse gas emissions. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Hydrocarbon origin and reservoir forming model research of Longwangmiao Formation, Moxi-Gaoshiti area, Sichuan Basin

    Directory of Open Access Journals (Sweden)

    Mindong Jin

    2016-06-01

    Full Text Available This paper focuses on the Longwangmiao gas reservoir in Moxi-Gaoshiti area, Sichuan Basin. Starting from the tectonic evolution perspective, though comparing biological marker compound and analyzing fluid inclusions, the oil & gas origin and accumulation evolution of Longwangmiao Formation are systematic studied with reference to the burial-thermal evolution of single well geological history in the study area. It is suggested that the oil & gas reservoir is generally characterized by early accumulation, multi-stage filling, late cracking and later adjustment. The oil and gas were mainly sourced from lower Cambrian Qiongzhusi Formation, partly from the Permian source rock. During the geological period, 3 major oil & gas fillings occurred in the Longwangmiao Formation, namely Caledonian-Hercynian filling that was small in scale and produced the first phase of paleo-oil reservoir that soon destroyed by Caledonian movement uplift, large-scale Permian filling that gave rise to the second-phase of paleo-oil reservoir and the Triassic-Jurassic filling that enriched the second phase of paleo-oil reservoir. Finally, the paleo-oil reservoir experienced an in-situ cracking during the cretaceous period that gave rise to a natural gas reservoir and left behind carbonaceous bitumen and oily bitumen in the holes of the Longwangmiao Formation.

  13. Deduction of reservoir operating rules for application in global hydrological models

    Directory of Open Access Journals (Sweden)

    H. M. Coerver

    2018-01-01

    Full Text Available A big challenge in constructing global hydrological models is the inclusion of anthropogenic impacts on the water cycle, such as caused by dams. Dam operators make decisions based on experience and often uncertain information. In this study information generally available to dam operators, like inflow into the reservoir and storage levels, was used to derive fuzzy rules describing the way a reservoir is operated. Using an artificial neural network capable of mimicking fuzzy logic, called the ANFIS adaptive-network-based fuzzy inference system, fuzzy rules linking inflow and storage with reservoir release were determined for 11 reservoirs in central Asia, the US and Vietnam. By varying the input variables of the neural network, different configurations of fuzzy rules were created and tested. It was found that the release from relatively large reservoirs was significantly dependent on information concerning recent storage levels, while release from smaller reservoirs was more dependent on reservoir inflows. Subsequently, the derived rules were used to simulate reservoir release with an average Nash–Sutcliffe coefficient of 0.81.

  14. Deduction of reservoir operating rules for application in global hydrological models

    Science.gov (United States)

    Coerver, Hubertus M.; Rutten, Martine M.; van de Giesen, Nick C.

    2018-01-01

    A big challenge in constructing global hydrological models is the inclusion of anthropogenic impacts on the water cycle, such as caused by dams. Dam operators make decisions based on experience and often uncertain information. In this study information generally available to dam operators, like inflow into the reservoir and storage levels, was used to derive fuzzy rules describing the way a reservoir is operated. Using an artificial neural network capable of mimicking fuzzy logic, called the ANFIS adaptive-network-based fuzzy inference system, fuzzy rules linking inflow and storage with reservoir release were determined for 11 reservoirs in central Asia, the US and Vietnam. By varying the input variables of the neural network, different configurations of fuzzy rules were created and tested. It was found that the release from relatively large reservoirs was significantly dependent on information concerning recent storage levels, while release from smaller reservoirs was more dependent on reservoir inflows. Subsequently, the derived rules were used to simulate reservoir release with an average Nash-Sutcliffe coefficient of 0.81.

  15. Towards an Improved Represenation of Reservoirs and Water Management in a Land Surface-Hydrology Model

    Science.gov (United States)

    Yassin, F.; Anis, M. R.; Razavi, S.; Wheater, H. S.

    2017-12-01

    Water management through reservoirs, diversions, and irrigation have significantly changed river flow regimes and basin-wide energy and water balance cycles. Failure to represent these effects limits the performance of land surface-hydrology models not only for streamflow prediction but also for the estimation of soil moisture, evapotranspiration, and feedbacks to the atmosphere. Despite recent research to improve the representation of water management in land surface models, there remains a need to develop improved modeling approaches that work in complex and highly regulated basins such as the 406,000 km2 Saskatchewan River Basin (SaskRB). A particular challenge for regional and global application is a lack of local information on reservoir operational management. To this end, we implemented a reservoir operation, water abstraction, and irrigation algorithm in the MESH land surface-hydrology model and tested it over the SaskRB. MESH is Environment Canada's Land Surface-hydrology modeling system that couples Canadian Land Surface Scheme (CLASS) with hydrological routing model. The implemented reservoir algorithm uses an inflow-outflow relationship that accounts for the physical characteristics of reservoirs (e.g., storage-area-elevation relationships) and includes simplified operational characteristics based on local information (e.g., monthly target volume and release under limited, normal, and flood storage zone). The irrigation algorithm uses the difference between actual and potential evapotranspiration to estimate irrigation water demand. This irrigation demand is supplied from the neighboring reservoirs/diversion in the river system. We calibrated the model enabled with the new reservoir and irrigation modules in a multi-objective optimization setting. Results showed that the reservoir and irrigation modules significantly improved the MESH model performance in generating streamflow and evapotranspiration across the SaskRB and that this our approach provides

  16. Characterization of pediatric microtia cartilage: a reservoir of chondrocytes for auricular reconstruction using tissue engineering strategies.

    Science.gov (United States)

    Melgarejo-Ramírez, Y; Sánchez-Sánchez, R; García-López, J; Brena-Molina, A M; Gutiérrez-Gómez, C; Ibarra, C; Velasquillo, C

    2016-09-01

    The external ear is composed of elastic cartilage. Microtia is a congenital malformation of the external ear that involves a small reduction in size or a complete absence. The aim of tissue engineering is to regenerate tissues and organs clinically implantable based on the utilization of cells and biomaterials. Remnants from microtia represent a source of cells for auricular reconstruction using tissue engineering. To examine the macromolecular architecture of microtia cartilage and behavior of chondrocytes, in order to enrich the knowledge of this type of cartilage as a cell reservoir. Auricular cartilage remnants were obtained from pediatric patients with microtia undergoing reconstructive procedures. Extracellular matrix composition was characterized using immunofluorescence and histological staining methods. Chondrocytes were isolated and expanded in vitro using a mechanical-enzymatic protocol. Chondrocyte phenotype was analyzed using qualitative PCR. Microtia cartilage preserves structural organization similar to healthy elastic cartilage. Extracellular matrix is composed of typical cartilage proteins such as type II collagen, elastin and proteoglycans. Chondrocytes displayed morphological features similar to chondrocytes derived from healthy cartilage, expressing SOX9, COL2 and ELN, thus preserving chondral phenotype. Cell viability was 94.6 % during in vitro expansion. Elastic cartilage from microtia has similar characteristics, both architectural and biochemical to healthy cartilage. We confirmed the suitability of microtia remnant as a reservoir of chondrocytes with potential to be expanded in vitro, maintaining phenotypical features and viability. Microtia remnants are an accessible source of autologous cells for auricular reconstruction using tissue engineering strategies.

  17. Integrated petrophysical and reservoir characterization workflow to enhance permeability and water saturation prediction

    Science.gov (United States)

    Al-Amri, Meshal; Mahmoud, Mohamed; Elkatatny, Salaheldin; Al-Yousef, Hasan; Al-Ghamdi, Tariq

    2017-07-01

    Accurate estimation of permeability is essential in reservoir characterization and in determining fluid flow in porous media which greatly assists optimize the production of a field. Some of the permeability prediction techniques such as Porosity-Permeability transforms and recently artificial intelligence and neural networks are encouraging but still show moderate to good match to core data. This could be due to limitation to homogenous media while the knowledge about geology and heterogeneity is indirectly related or absent. The use of geological information from core description as in Lithofacies which includes digenetic information show a link to permeability when categorized into rock types exposed to similar depositional environment. The objective of this paper is to develop a robust combined workflow integrating geology and petrophysics and wireline logs in an extremely heterogeneous carbonate reservoir to accurately predict permeability. Permeability prediction is carried out using pattern recognition algorithm called multi-resolution graph-based clustering (MRGC). We will bench mark the prediction results with hard data from core and well test analysis. As a result, we showed how much better improvements are achieved in the permeability prediction when geology is integrated within the analysis. Finally, we use the predicted permeability as an input parameter in J-function and correct for uncertainties in saturation calculation produced by wireline logs using the classical Archie equation. Eventually, high level of confidence in hydrocarbon volumes estimation is reached when robust permeability and saturation height functions are estimated in presence of important geological details that are petrophysically meaningful.

  18. 2D X-ray scanner and its uses in laboratory reservoir characterization measurements

    Energy Technology Data Exchange (ETDEWEB)

    Maloney, D.; Doggett, K.

    1997-08-01

    X-ray techniques are used in petroleum laboratories for a variety of reservoir characterization measurements. This paper describes the configuration of a 2D X-ray scanner and many of the ways in which it simplifies and improves accuracy`s of laboratory measurements. Linear X-ray scanners are most often used to provide descriptions of fluid saturations within core plugs during flow tests. We configured our linear scanner for both horizontal and vertical movement. Samples can be scanned horizontally, vertically, or according to horizontal and vertical grids. X-ray measurements are fast, allowing measurements of two- and three-phase fluid saturations during both steady- and unsteady-state flow processes. Rock samples can be scanned while they are subjected to stress, pore pressure, and temperature conditions simulating those of a petroleum reservoir. Many types of measurements are possible by selecting appropriate X-ray power settings, dopes, filters, and collimator configurations. The scanner has been used for a variety of applications besides fluid saturation measurements. It is useful for measuring porosity distributions in rocks, concentrations of X-ray dopes within flow streams during tracer tests, gap widths in fracture flow cells, fluid interface levels in PVT cells and fluid separators, and other features and phenomena.

  19. Sedimentological Characterization of a Deepwater Methane Hydrate Reservoir in Green Canyon 955, Northern Gulf of Mexico

    Science.gov (United States)

    Meazell, K.; Flemings, P. B.

    2017-12-01

    Grain size is a controlling factor of hydrate saturation within a Pleistocene channel-levee system investigated by the UT-GOM2-1 expedition within the deepwater northern Gulf of Mexico. Laser diffraction and settling experiments conducted on sediments from 413-440 meters below the seafloor reveal the presence of two interbedded lithologic units, identified as a silty sand and a clayey silt, according Shepard's classification system. The sand-rich lithofacies has low density and high p-wave velocity, suggesting a high degree of hydrate saturation. Conversely, the clay and silt dominated lithofacies is characterized by a higher density and low p-wave velocity, suggesting low hydrate saturation. The sand-rich lithofacies is well-sorted and displays abundant ripple lamination, indicative of deposition within a high-energy environment. The clayey-silt is poorly-sorted and lacks sedimentary structures. The two lithofacies are interbedded throughout the reservoir unit; however, the relative abundance of the sand-rich lithofacies increases with depth, suggesting a potential decrease in flow energy or sediment flux over time, resulting in the most favorable reservoir properties near the base of the unit.

  20. Reservoir management

    International Nuclear Information System (INIS)

    Satter, A.; Varnon, J.E.; Hoang, M.T.

    1992-01-01

    A reservoir's life begins with exploration leading to discovery followed by delineation of the reservoir, development of the field, production by primary, secondary and tertiary means, and finally to abandonment. Sound reservoir management is the key to maximizing economic operation of the reservoir throughout its entire life. Technological advances and rapidly increasing computer power are providing tools to better manage reservoirs and are increasing the gap between good and neutral reservoir management. The modern reservoir management process involves goal setting, planning, implementing, monitoring, evaluating, and revising plans. Setting a reservoir management strategy requires knowledge of the reservoir, availability of technology, and knowledge of the business, political, and environmental climate. Formulating a comprehensive management plan involves depletion and development strategies, data acquisition and analyses, geological and numerical model studies, production and reserves forecasts, facilities requirements, economic optimization, and management approval. This paper provides management, engineers geologists, geophysicists, and field operations staff with a better understanding of the practical approach to reservoir management using a multidisciplinary, integrated team approach

  1. Characterization of the deep microbial life in the Altmark natural gas reservoir

    Science.gov (United States)

    Morozova, D.; Alawi, M.; Vieth-Hillebrand, A.; Kock, D.; Krüger, M.; Wuerdemann, H.; Shaheed, M.

    2010-12-01

    Within the framework of the CLEAN project (CO2 Largescale Enhanced gas recovery in the Altmark Natural gas field) technical basics with special emphasis on process monitoring are explored by injecting CO2 into a gas reservoir. Our study focuses on the investigation of the in-situ microbial community of the Rotliegend natural gas reservoir in the Altmark, located south of the city Salzwedel, Germany. In order to characterize the microbial life in the extreme habitat we aim to localize and identify microbes including their metabolism influencing the creation and dissolution of minerals. The ability of microorganisms to speed up dissolution and formation of minerals might result in changes of the local permeability and the long-term safety of CO2 storage. However, geology, structure and chemistry of the reservoir rock and the cap rock as well as interaction with saline formation water and natural gases and the injected CO2 affect the microbial community composition and activity. The reservoir located at the depth of approximately 3500 m, is characterised by high salinity (420 g/l) and temperatures up to 127°C. It represents an extreme environment for microbial life and therefore the main focus is on hyperthermophilic, halophilic anaerobic microorganisms. In consequence of the injection of large amounts of CO2 in the course of a commercial EGR (Enhanced Gas Recovery), the environmental conditions (e.g. pH, temperature, pressure and solubility of minerals) for the autochthonous microorganisms will change. Genetic profiling of amplified 16S rRNA genes are applied for detecting structural changes in the community by using PCR- SSCP (PCR-Single-Strand-Conformation Polymorphism), DGGE (Denaturing Gradient Gel Electrophoresis) and 16S rRNA cloning. First results of the baseline survey indicate the presence of microorganisms similar to representatives from other deep environments. The sequence analyses revealed the presence of several H2-oxidising bacteria (Hydrogenophaga sp

  2. Modeling surface energy fluxes and thermal dynamics of a seasonally ice-covered hydroelectric reservoir.

    Science.gov (United States)

    Wang, Weifeng; Roulet, Nigel T; Strachan, Ian B; Tremblay, Alain

    2016-04-15

    The thermal dynamics of human created northern reservoirs (e.g., water temperatures and ice cover dynamics) influence carbon processing and air-water gas exchange. Here, we developed a process-based one-dimensional model (Snow, Ice, WAater, and Sediment: SIWAS) to simulate a full year's surface energy fluxes and thermal dynamics for a moderately large (>500km(2)) boreal hydroelectric reservoir in northern Quebec, Canada. There is a lack of climate and weather data for most of the Canadian boreal so we designed SIWAS with a minimum of inputs and with a daily time step. The modeled surface energy fluxes were consistent with six years of observations from eddy covariance measurements taken in the middle of the reservoir. The simulated water temperature profiles agreed well with observations from over 100 sites across the reservoir. The model successfully captured the observed annual trend of ice cover timing, although the model overestimated the length of ice cover period (15days). Sensitivity analysis revealed that air temperature significantly affects the ice cover duration, water and sediment temperatures, but that dissolved organic carbon concentrations have little effect on the heat fluxes, and water and sediment temperatures. We conclude that the SIWAS model is capable of simulating surface energy fluxes and thermal dynamics for boreal reservoirs in regions where high temporal resolution climate data are not available. SIWAS is suitable for integration into biogeochemical models for simulating a reservoir's carbon cycle. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Deep-water Reservoir Modelling Using a volume-based approach on Full-Offset Seismic Data: Etim Field, Offshore Nigeria

    International Nuclear Information System (INIS)

    Nwaeri, E.; Zimbrick, G.; Proett, B.

    2002-01-01

    Reservoir characterization of deep-water deposits is a challenging task. Major issues to address include: (1) prediction of sand distribution away from well control, (2) definition of reservoir geometry and size, and (3) spatial placement of sand bodies in the geologic model. In a typical deep-water setting, lithostratigraphic correlation using well logs has been found to be unreliable. Seismic correlation is critical, but complications from mixed-impedance reservoir, and variations in frequency/phase content of available full stack data can arise.We describe a reservoir description workflow that utilizes both volume-and map-based conditioning tools, in the absence of AVO products. A good density of interpreted horizons was used to provide stratigraphic control on the volume interpretation techniques. Map pattern analysis of horizon slices helped focus environment of deposition (EOD) interpretations on key areas of reservoir development.A seismic wedge model helped develop an interpretation strategy and assess seismic data quality. Results showed that seed detection of trough-peak pairs gave a reasonable prediction of reservoir distribution at Etim.Seismic attributes were used to calibrate and predict net sand thickness. The predictions were integrated with EOD maps and well control to provide final net sand maps. Extracted geobodies from the sculpted seismic data were used to place sands in their proper position in the geologic model.The resulting geologic model preserves spatial positioning of the seismically derived reservoir elements and provides better definition of reservoir connectivity. This workflow is appropriate for fields where multi-volume (AVO) seismic data are unavailable and 3-D positioning of reservoir elements is required

  4. An integrated petrophysical-geophysical approach for the characterization of a potential caprock-reservoir system for CO2 storage.

    Science.gov (United States)

    Fais, Silvana; Ligas, Paola; Cuccuru, Francesco; Casula, Giuseppe; Giovanna Bianchi, Maria; Maggio, Enrico; Plaisant, Alberto; Pettinau, Alberto

    2016-04-01

    The selection of a CO2 geologic storage site requires the choice of a study site suitable for the characterization in order to create a robust experimental database especially regarding the spatial petrophysical heterogeneities and elasto-mechanical properties of the rocks that make up a potential caprock-reservoir system. In our study the petrophysical and elasto-mechanical characterization began in a previously well drilled area in the northern part of the Sulcis coal basin (Nuraxi Figus area - SW Sardinia - Italy) where crucial geologic data were recovered from high-quality samples from stratigraphic wells and from mining galleries. The basin represents one of the most important Italian carbon reserves characterized by a great mining potential. In the study area, the Middle Eocene - Lower Oligocene Cixerri Fm. made up of terrigeneous continental rocks and the Upper Thanetian - Lower Ypresian Miliolitico Carbonate Complex in the Sulcis coal basin have been identified respectively as potential caprock and reservoir for CO2 storage. Petrophysical and geophysical investigations were carried out by a great number of laboratory tests on the core samples and in situ measurements on a mining gallery in order to characterize the potential caprock-reservoir system and to substantially reduce geologic uncertainty in the storage site characterization and in the geological and numerical modelling for the evaluation of CO2 storage capacity. In order to better define the spatial distribution of the petrophysical heterogeneity, the seismic responses from the caprock-reservoir system formations were also analysed and correlated with the petrophysical and elasto-mechanical properties In a second step of this work, we also analysed the tectonic stability of the study area by the integrated application of remote-sensing monitoring spatial geodetic techniques. In particular, the global positioning system (GPS) and interferometric synthetic aperture radar (inSAR) were considered

  5. Construction of a carbonate reservoir model using pressure transient data : field case study

    Energy Technology Data Exchange (ETDEWEB)

    Taheri, S. [Petro-Iran, (Iran, Islamic Republic of); Ghanizadeh, M. [Tehran Energy, (Iran, Islamic Republic of); Haghighi, M. [Tehran Univ., (Iran, Islamic Republic of)

    2004-07-01

    Pressure transient data was integrated with other reservoir information to create a geological model of a carbonate reservoir in the Salaman offshore field in Iran. The model was created using seismic and well log data as well as the interpretation of 99 well tests performed in this field. Several features such as sealing faults, aquifer, fracturing and layering systems were observed. Two faults were identified in the northern part of the reservoir. The distance between the major fault and well number 27 was less than predicted from seismic data. An active aquifer and minor fault were also identified near well number 6. A fracture system was identified around well number 22. Most well tests showed communication between different layers of the reservoirs, suggesting interconnected layers in terms of geology. All calculated permeabilities from the well tests were found to be significantly higher than those from core analysis, suggesting that discrete fractures exist throughout the reservoir. The northern region of the reservoir has the highest permeability values and the lowest values are observed in the central part of the reservoir. 18 refs., 6 figs.

  6. Application of integrated reservoir management and reservoir characterization to optimize infill drilling. Quarterly progress report, June 13, 1996--September 12, 1996

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-09-12

    At this time, eighteen (18) 10-acre infill wells have been drilled as part of the Field Demonstration phase of the project. Of the fourteen producing wells drilled to date, twelve are currently on production, and ten are pumped-off and producing at stable rates. Current Unit production is approximately 3,600-3,700 STBO/D, and approximately 850 STBO/D incremental production has been added to date. The remaining producing well and four injection wells are currently being completed. A change in the Statement of Work has been approved so that we can drill additional 10-acre infill wells during the next quarter as budget constraints allow. Production flowlines are laid for each new producing well as they are put on production. Injection lines are being laid for the injection wells as they are completed. All data required for the validation of the Budget Period I Reservoir Characterization, Reservoir Management, and Reservoir Simulation Studies are being acquired and analyzed during the Field Demonstration Period.

  7. Actualistic and Geochemical Modeling of Reservoir Rock, CO2 and Formation Fluid Interaction, Citronelle Oil Field, Alabama

    Energy Technology Data Exchange (ETDEWEB)

    Weislogel, Amy [West Virginia Univ., Morgantown, WV (United States)

    2014-01-31

    This report includes description of the Citronelle field study area and the work carried out in the project to characterize the geology and composition of reservoir rock material and to collect an analyze the geochemical composition of produced fluid waters from the Citronelle field. Reservoir rock samples collected from well bore core were made into thin-sections and assessed for textural properties, including pore types and porosity distribution. Compositional framework grain modal data were collected via point-counting, and grain and cement mineralogy was assessed using SEM-EDS. Geochemistry of fluid samples is described and modeled using PHREEQC. Composition of rock and produced fluids were used as inputs for TOUGHREACT reactive transport modeling, which determined the rock-fluid system was in disequilibrium.

  8. CHARACTERIZATION OF IN-SITU STRESS AND PERMEABILITY IN FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Daniel R. Burns; Nafi Toksoz

    2006-03-16

    Using a 3-D finite difference method with a rotated-staggered-grid (RSG) scheme we generated synthetic seismograms for a reservoir model consisting of three horizontal layers with the middle layer containing parallel, equally spaced fractures. By separating and analyzing the backscattered signals in the FK domain, we can obtain an estimate of the fracture spacing. The fracture spacing is estimated by taking one-half of the reciprocal of the dominant wavenumber of the backscattered energy in data acquired normal to the fractures. FK analysis for fracture spacing estimation was successfully applied to these model results, with particular focus on PS converted waves. The method was then tested on data from the Emilio Field. The estimated fracture spacing from the dominant wavenumber values in time windows at and below the reservoir level is 25-40m. A second approach for fracture spacing estimation is based on the observation that interference of forward and backscattered energy from fractures introduces notches in the frequency spectra of the scattered wavefield for data acquired normal to the fracture strike. The frequency of these notches is related to the spacing of the fractures. This Spectral Notch Method was also applied to the Emilio data, with the resulting range of fracture spacing estimates being 25-50m throughout the field. The dominant spacing fracture spacing estimate is about 30-40 m, which is very similar to the estimates obtained from the FK method.

  9. Increasing the predictive power of geostatistical reservoir models by integration of geological constraints from stratigraphic forward modeling

    NARCIS (Netherlands)

    Sacchi, Q.; Borello, E.S.; Weltje, G.J.; Dalman, R.

    2016-01-01

    Current static reservoir models are created by quantitative integration of interpreted well and seismic data through geostatistical tools. In these models, equiprobable realizations of structural settings and property distributions can be generated by stochastic simulation techniques. The

  10. A snow and ice melt seasonal prediction modelling system for Alpine reservoirs

    Science.gov (United States)

    Förster, Kristian; Oesterle, Felix; Hanzer, Florian; Schöber, Johannes; Huttenlau, Matthias; Strasser, Ulrich

    2016-10-01

    The timing and the volume of snow and ice melt in Alpine catchments are crucial for management operations of reservoirs and hydropower generation. Moreover, a sustainable reservoir operation through reservoir storage and flow control as part of flood risk management is important for downstream communities. Forecast systems typically provide predictions for a few days in advance. Reservoir operators would benefit if lead times could be extended in order to optimise the reservoir management. Current seasonal prediction products such as the NCEP (National Centers for Environmental Prediction) Climate Forecast System version 2 (CFSv2) enable seasonal forecasts up to nine months in advance, with of course decreasing accuracy as lead-time increases. We present a coupled seasonal prediction modelling system that runs at monthly time steps for a small catchment in the Austrian Alps (Gepatschalm). Meteorological forecasts are obtained from the CFSv2 model. Subsequently, these data are downscaled to the Alpine Water balance And Runoff Estimation model AWARE running at monthly time step. Initial conditions are obtained using the physically based, hydro-climatological snow model AMUNDSEN that predicts hourly fields of snow water equivalent and snowmelt at a regular grid with 50 m spacing. Reservoir inflow is calculated taking into account various runs of the CFSv2 model. These simulations are compared with observed inflow volumes for the melting and accumulation period 2015.

  11. Final Report to DOE EERE – Geothermal Technologies Program Project Title: Monitoring and modeling of fluid flow in a developing enhanced geothermal system (EGS) reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Fehler, Michael [Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)

    2017-04-19

    The primary objective of this project was to improve our ability to predict performance of an Enhanced Geothermal System (EGS) reservoir over time by relating, in a quantitative manner, microseismic imaging with fluid and temperature changes within the reservoir. Historically, microseismic data have been used qualitatively to place bounds on the growth of EGS reservoirs created by large hydraulic fracturing experiments. Previous investigators used an experimentally based fracture opening relationship (fracture aperture as a function of pressure), the spatial extent of microseismic events, and some assumptions about fracture frequency to determine the size of an EGS reservoir created during large pumping tests. We addressed a number of issues (1) locating microearthquakes that occur during hydraulic fracturing, (2) obtaining more information about a reservoir than the microearthquake locations from the microearthquake data, for example, information about the seismic velocity structure of the reservoir or the scattering of seismic waves within the reservoir, (3) developing an improved methodology for estimating properties of fractures that intersect wellbores in a reservoir, and (4) developing a conceptual model for explaining the downward growth of observed seismicity that accompanies some hydraulic injections into geothermal reservoirs. We used two primary microseismic datasets for our work. The work was motivated by a dataset from the Salak Geothermal Field in Indonesia where seismicity accompanying a hydraulic injection was observed to migrate downward. We also used data from the Soultz EGS site in France. We also used Vertical Seismic Profiling data from a well in the United States. The work conducted is of benefit for characterizing reservoirs that are created by hydraulic fracturing for both EGS and for petroleum recovery.

  12. INTEGRATED GEOLOGIC-ENGINEERING MODEL FOR REEF AND CARBONATE SHOAL RESERVOIRS ASSOCIATED WITH PALEOHIGHS: UPPER JURASSIC SMACKOVER FORMATION, NORTHEASTERN GULF OF MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    Ernest A. Mancini

    2004-02-25

    The University of Alabama, in cooperation with Texas A&M University, McGill University, Longleaf Energy Group, Strago Petroleum Corporation, and Paramount Petroleum Company, has undertaken an integrated, interdisciplinary geoscientific and engineering research project. The project is designed to characterize and model reservoir architecture, pore systems and rock-fluid interactions at the pore to field scale in Upper Jurassic Smackover reef and carbonate shoal reservoirs associated with varying degrees of relief on pre-Mesozoic basement paleohighs in the northeastern Gulf of Mexico. The project effort includes the prediction of fluid flow in carbonate reservoirs through reservoir simulation modeling which utilizes geologic reservoir characterization and modeling and the prediction of carbonate reservoir architecture, heterogeneity and quality through seismic imaging. The primary goal of the project is to increase the profitability, producibility and efficiency of recovery of oil from existing and undiscovered Upper Jurassic fields characterized by reef and carbonate shoals associated with pre-Mesozoic basement paleohighs. Geoscientific reservoir property, geophysical seismic attribute, petrophysical property, and engineering property characterization has shown that reef (thrombolite) and shoal reservoir lithofacies developed on the flanks of high-relief crystalline basement paleohighs (Vocation Field example) and on the crest and flanks of low-relief crystalline basement paleohighs (Appleton Field example). The reef thrombolite lithofacies have higher reservoir quality than the shoal lithofacies due to overall higher permeabilities and greater interconnectivity. Thrombolite dolostone flow units, which are dominated by dolomite intercrystalline and vuggy pores, are characterized by a pore system comprised of a higher percentage of large-sized pores and larger pore throats. Rock-fluid interactions (diagenesis) studies have shown that although the primary control on

  13. Geochemical analysis of atlantic rim water, carbon county, wyoming: New applications for characterizing coalbed natural gas reservoirs

    Science.gov (United States)

    McLaughlin, J.F.; Frost, C.D.; Sharma, Shruti

    2011-01-01

    Coalbed natural gas (CBNG) production typically requires the extraction of large volumes of water from target formations, thereby influencing any associated reservoir systems. We describe isotopic tracers that provide immediate data on the presence or absence of biogenic natural gas and the identify methane-containing reservoirs are hydrologically confined. Isotopes of dissolved inorganic carbon and strontium, along with water quality data, were used to characterize the CBNG reservoirs and hydrogeologic systems of Wyoming's Atlantic Rim. Water was analyzed from a stream, springs, and CBNG wells. Strontium isotopic composition and major ion geochemistry identify two groups of surface water samples. Muddy Creek and Mesaverde Group spring samples are Ca-Mg-S04-type water with higher 87Sr/86Sr, reflecting relatively young groundwater recharged from precipitation in the Sierra Madre. Groundwaters emitted from the Lewis Shale springs are Na-HCO3-type waters with lower 87Sr/86Sr, reflecting sulfate reduction and more extensive water-rock interaction. To distinguish coalbed waters, methanogenically enriched ??13CDIC wasused from other natural waters. Enriched ??13CDIC, between -3.6 and +13.3???, identified spring water that likely originates from Mesaverde coalbed reservoirs. Strongly positive ??13CDIC, between +12.6 and +22.8???, identified those coalbed reservoirs that are confined, whereas lower ??13CDIC, between +0.0 and +9.9???, identified wells within unconfined reservoir systems. Copyright ?? 2011. The American Association of Petroleum Geologists. All rights reserved.

  14. Biogeochemical mass balances in a turbid tropical reservoir. Field data and modelling approach

    Science.gov (United States)

    Phuong Doan, Thuy Kim; Némery, Julien; Gratiot, Nicolas; Schmid, Martin

    2014-05-01

    The turbid tropical Cointzio reservoir, located in the Trans Mexican Volcanic Belt (TMVB), behaves as a warm monomictic water body (area = 6 km2, capacity 66 Mm3, residence time ~ 1 year). It is strategic for the drinking water supply of the city of Morelia, capital of the state of Michoacán, and for downstream irrigation during the dry season. This reservoir is a perfect example of a human-impacted system since its watershed is mainly composed of degraded volcanic soils and is subjected to high erosion processes and agricultural loss. The reservoir is threatened by sediment accumulation and nutrients originating from untreated waters in the upstream watershed. The high content of very fine clay particles and the lack of water treatment plants lead to serious episodes of eutrophication (up to 70 μg chl. a L-1), high levels of turbidity (Secchi depth water vertical profiles, reservoir inflow and outflow) we determined suspended sediment (SS), carbon (C), nitrogen (N) and phosphorus (P) mass balances. Watershed SS yields were estimated at 35 t km2 y-1 of which 89-92 % were trapped in the Cointzio reservoir. As a consequence the reservoir has already lost 25 % of its initial storage capacity since its construction in 1940. Nutrient mass balances showed that 50 % and 46 % of incoming P and N were retained by sedimentation, and mainly eliminated through denitrification respectively. Removal of C by 30 % was also observed both by sedimentation and through gas emission. To complete field data analyses we examined the ability of vertical one dimensional (1DV) numerical models (Aquasim biogeochemical model coupled with k-ɛ mixing model) to reproduce the main biogeochemical cycles in the Cointzio reservoir. The model can describe all the mineralization processes both in the water column and in the sediment. The values of the entire mass balance of nutrients and of the mineralization rates (denitrification and aerobic benthic mineralization) calculated from the model

  15. Plankton diversity and limnological characterization in two shallow tropical urban reservoirs of Pernambuco State, Brazil.

    Science.gov (United States)

    Almeida, Viviane L S; Melão, Maria da Graça G; Moura, Ariadne N

    2012-06-01

    Plankton diversity, physical and chemical variables and chlorophyll a were analyzed in two shallow urban reservoirs with different trophic degrees on Pernambuco State, northeastern Brazil. High eutrophication levels were observed in Apipucos reservoir, while Prata reservoir was considered oligotrophic. Values reported for physical and chemical variables and chlorophyll a differed among the studied ecosystems. Richness and plankton diversity were higher in Apipucos reservoir especially for phytoplankton. The presence of potential toxic Cyanophyceae in both reservoirs reflects a problem mainly to Prata reservoir, which is used for public water supply. Differences were observed for some variables among sites of study in Apipucos reservoir, while the differences among strata were negligible in both reservoirs, reflecting the water column mixing by wind action. Rainfall regulated the temporal dynamics for the analyzed variables, with significant seasonal differences, mainly for the major of limnological variables in Apipucos reservoir. Plankton diversity was higher in Apipucos reservoir, especially to phytoplankton, showing that eutrophication and pollution can favor plankton diversity in tropical urban shallow reservoirs.

  16. Sediment Deposition Risk Analysis and PLSR Model Research for Cascade Reservoirs Upstream of the Yellow River

    Directory of Open Access Journals (Sweden)

    Jie Yang

    2015-01-01

    Full Text Available It is difficult to effectively identify and eliminate the multiple correlation influence among the independent factors by least-squares regression. Focusing on this insufficiency, the sediment deposition risk of cascade reservoirs and fitting model of sediment flux into the reservoir are studied. The partial least-squares regression (PLSR method is adopted for modeling analysis; the model fitting is organically combined with the non-model-style data content analysis, so as to realize the regression model, data structure simplification, and multiple correlations analysis among factors; meanwhile the accuracy of the model is ensured through cross validity check. The modeling analysis of sediment flux into the cascade reservoirs of Long-Liu section upstream of the Yellow River indicates that partial least-squares regression can effectively overcome the multiple correlation influence among factors, and the isolated factor variables have better ability to explain the physical cause of measured results.

  17. Geomechanical characterization and reservoir simulation of a carbon dioxide sequestration project in a mature oil field, Teapot Dome, WY

    Science.gov (United States)

    Chiaramonte, Laura

    In this dissertation, I present my contribution towards the understanding and prediction of the risk of CO2 leakage through natural pathways (i.e. faults and fractures). The main portion of this dissertation deals with geomechanical aspects of CO2 Sequestration in Teapot Dome, WY, a mature oil field. The last study investigates the use of induce microseismicity to enhance permeability and injectivity in tight reservoirs and to monitor carbon sequestration projects. In the first three projects, the Tensleep Formation, a Pennsylvanian age eolian fractured sandstone, is evaluated as the target horizon for a pilot CO2 EOR-carbon storage experiment, in a three-way closure trap against a bounding fault, termed the S1 fault. In the first study, a geomechanical model of the Tensleep Fm. has been developed to evaluate the potential for CO2 injection inducing slip on the S1 fault and thus threatening seal integrity. The geomechanical analysis demonstrated that CO2 sequestration will not induce slip on the reservoir-bounding fault, nor is cracking the cap rock a concern. In the second study, a 3D reservoir model and fluid flow simulation of the Tensleep Fm., under these geomechanical constraints, was developed to model the migration of the injected CO2 as well as to obtain limits on the rates and volumes of CO2 that can be injected without compromising seal integrity. The results of the numerical simulations corroborate the analytical results of the geomechanical analysis that seal integrity will not be compromised by the pilot injection. In the third study, we test an Amplitude Versus Angle and Azimuth (AVAZ) analysis to identify the presence of fractures using wide-azimuth 3D seismic data. The objective of the project was to obtain a 3D characterization of the fracture network on both the reservoir and the caprock that will allow for a more accurate assessment of the impact of these features in reservoir permeability and in the risk of CO2 leakage. The AVAZ results were

  18. An Integrated Approach to Characterizing Bypassed Oil in Heterogeneous and Fractured Reservoirs Using Partitioning Tracers

    Energy Technology Data Exchange (ETDEWEB)

    Akhil Datta-Gupta

    2006-12-31

    We explore the use of efficient streamline-based simulation approaches for modeling partitioning interwell tracer tests in hydrocarbon reservoirs. Specifically, we utilize the unique features of streamline models to develop an efficient approach for interpretation and history matching of field tracer response. A critical aspect here is the underdetermined and highly ill-posed nature of the associated inverse problems. We have investigated the relative merits of the traditional history matching ('amplitude inversion') and a novel travel time inversion in terms of robustness of the method and convergence behavior of the solution. We show that the traditional amplitude inversion is orders of magnitude more non-linear and the solution here is likely to get trapped in local minimum, leading to inadequate history match. The proposed travel time inversion is shown to be extremely efficient and robust for practical field applications. The streamline approach is generalized to model water injection in naturally fractured reservoirs through the use of a dual media approach. The fractures and matrix are treated as separate continua that are connected through a transfer function, as in conventional finite difference simulators for modeling fractured systems. A detailed comparison with a commercial finite difference simulator shows very good agreement. Furthermore, an examination of the scaling behavior of the computation time indicates that the streamline approach is likely to result in significant savings for large-scale field applications. We also propose a novel approach to history matching finite-difference models that combines the advantage of the streamline models with the versatility of finite-difference simulation. In our approach, we utilize the streamline-derived sensitivities to facilitate history matching during finite-difference simulation. The use of finite-difference model allows us to account for detailed process physics and compressibility effects

  19. Advanced reservoir characterization and evaluation of CO{sub 2} gravity drainage in the naturally fractured Spraberry Trend Area. Annual report, September 1, 1996--August 31, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Schechter, D.S.

    1998-07-01

    The overall goal of this project is to assess the economic feasibility of CO{sub 2} flooding the naturally fractured Spraberry Trend Area in West Texas. This objective is being accomplished by conducting research in four areas: (1) extensive characterization of the reservoirs, (2) experimental studies of crude oil/brine/rock (COBR) interaction in the reservoirs, (3) reservoir performance analysis, and (4) experimental investigations on CO{sub 2} gravity drainage in Spraberry whole cores. This report provides results of the second year of the five-year project for each of the four areas. In the first area, the author has completed the reservoir characterization, which includes matrix description and detection (from core-log integration) and fracture characterization. This information is found in Section 1. In the second area, the author has completed extensive inhibition experiments that strongly indicate that the weakly water-wet behavior of the reservoir rock may be responsible for poor waterflood response observed in many Spraberry fields. In the third area, the author has made significant progress in analytical and numerical simulation of performance in Spraberry reservoirs as seen in Section 3. In the fourth area, the author has completed several suites of CO{sub 2} gravity drainage in Spraberry and Berea whole cores at reservoir conditions and reported in Section 4. The results of these experiments have been useful in developing a model for free-fall gravity drainage and have validated the premise that CO{sub 2} will recover oil from tight, unconfined Spraberry matrix. The final three years of this project involves implementation of the CO{sub 2} pilot. Up to twelve new wells are planned in the pilot area; water injection wells to contain the CO{sub 2}, three production wells to monitor performance of CO{sub 2}, CO{sub 2} injection wells including one horizontal injection well and logging observation wells to monitor CO{sub 2} flood fronts. Results of drilling

  20. Development of a X-ray micro-tomograph and its application to reservoir rocks characterization

    International Nuclear Information System (INIS)

    Ferreira de Paiva, R.

    1995-10-01

    We describe the construction and application to studies in three dimensions of a laboratory micro-tomograph for the characterisation of heterogeneous solids at the scale of a few microns. The system is based on an electron microprobe and a two dimensional X-ray detector. The use of a low beam divergence for image acquisition allows use of simple and rapid reconstruction software whilst retaining reasonable acquisition times. Spatial resolutions of better than 3 microns in radiography and 10 microns in tomography are obtained. The applications of microtomography in the petroleum industry are illustrated by the study of fibre orientation in polymer composites, of the distribution of minerals and pore space in reservoir rocks, and of the interaction of salt water with a model porous medium. A correction for X-ray beam hardening is described and used to obtain improved discrimination of the phases present in the sample. In the case of a North Sea reservoir rock we show the possibility to distinguish quartz, feldspar and in certain zone kaolinite. The representativeness of the tomographic reconstruction is demonstrated by comparing the surface of the reconstructed specimen with corresponding images obtained in scanning electron microscopy. (author). 58 refs., 10 tabs., 71 photos

  1. HIV Model Parameter Estimates from Interruption Trial Data including Drug Efficacy and Reservoir Dynamics

    Science.gov (United States)

    Luo, Rutao; Piovoso, Michael J.; Martinez-Picado, Javier; Zurakowski, Ryan

    2012-01-01

    Mathematical models based on ordinary differential equations (ODE) have had significant impact on understanding HIV disease dynamics and optimizing patient treatment. A model that characterizes the essential disease dynamics can be used for prediction only if the model parameters are identifiable from clinical data. Most previous parameter identification studies for HIV have used sparsely sampled data from the decay phase following the introduction of therapy. In this paper, model parameters are identified from frequently sampled viral-load data taken from ten patients enrolled in the previously published AutoVac HAART interruption study, providing between 69 and 114 viral load measurements from 3–5 phases of viral decay and rebound for each patient. This dataset is considerably larger than those used in previously published parameter estimation studies. Furthermore, the measurements come from two separate experimental conditions, which allows for the direct estimation of drug efficacy and reservoir contribution rates, two parameters that cannot be identified from decay-phase data alone. A Markov-Chain Monte-Carlo method is used to estimate the model parameter values, with initial estimates obtained using nonlinear least-squares methods. The posterior distributions of the parameter estimates are reported and compared for all patients. PMID:22815727

  2. Application of reservoir characterization and advanced technology to improve recovery and economics in a lower quality shallow shelf carbonate reservoir. End of budget period report, August 3, 1994--December 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, A.R.; Hinterlong, G.; Watts, G.; Justice, J.; Brown, K.; Hickman, T.S.

    1997-12-01

    The Oxy West Welch project is designed to demonstrate how the use of advanced technology can improve the economics of miscible CO{sub 2} injection projects in a lower quality shallow shelf carbonate reservoir. The research and design phase primarily involves advanced reservoir characterization and accelerating the production response. The demonstration phase will implement the reservoir management plan based on an optimum miscible CO{sub 2} flood as designed in the initial phase. During Budget Period 1, work was completed on the CO{sub 2} stimulation treatments and the hydraulic fracture design. Analysis of the CO{sub 2} stimulation treatment provided a methodology for predicting results. The hydraulic fracture treatment proved up both the fracture design approach a and the use of passive seismic for mapping the fracture wing orientation. Although the 3-D seismic interpretation is still being integrated into the geologic model and interpretation of borehole seismic is still underway, the simulator has been enhanced to the point of giving good waterflood history matches. The simulator-forecasted results for an optimal designed miscible CO{sub 2} flood in the demonstration area gave sufficient economics to justify continuation of the project into Budget Period 2.

  3. In Situ Characterization of Splenic Brucella melitensis Reservoir Cells during the Chronic Phase of Infection in Susceptible Mice.

    Science.gov (United States)

    Hanot Mambres, Delphine; Machelart, Arnaud; Vanderwinden, Jean-Marie; De Trez, Carl; Ryffel, Bernhard; Letesson, Jean-Jacques; Muraille, Eric

    2015-01-01

    Brucella are facultative intracellular Gram-negative coccobacilli that chronically infect humans as well as domestic and wild-type mammals, and cause brucellosis. Alternatively activated macrophages (M2a) induced by IL-4/IL-13 via STAT6 signaling pathways have been frequently described as a favorable niche for long-term persistence of intracellular pathogens. Based on the observation that M2a-like macrophages are induced in the spleen during the chronic phase of B. abortus infection in mice and are strongly infected in vitro, it has been suggested that M2a macrophages could be a potential in vivo niche for Brucella. In order to test this hypothesis, we used a model in which infected cells can be observed directly in situ and where the differentiation of M2a macrophages is favored by the absence of an IL-12-dependent Th1 response. We performed an in situ analysis by fluorescent microscopy of the phenotype of B. melitensis infected spleen cells from intranasally infected IL-12p40-/- BALB/c mice and the impact of STAT6 deficiency on this phenotype. Most of the infected spleen cells contained high levels of lipids and expressed CD11c and CD205 dendritic cell markers and Arginase1, but were negative for the M2a markers Fizz1 or CD301. Furthermore, STAT6 deficiency had no effect on bacterial growth or the reservoir cell phenotype in vivo, leading us to conclude that, in our model, the infected cells were not Th2-induced M2a macrophages. This characterization of B. melitensis reservoir cells could provide a better understanding of Brucella persistence in the host and lead to the design of more efficient therapeutic strategies.

  4. Incorporating teleconnection information into reservoir operating policies using Stochastic Dynamic Programming and a Hidden Markov Model

    Science.gov (United States)

    Turner, Sean; Galelli, Stefano; Wilcox, Karen

    2015-04-01

    Water reservoir systems are often affected by recurring large-scale ocean-atmospheric anomalies, known as teleconnections, that cause prolonged periods of climatological drought. Accurate forecasts of these events -- at lead times in the order of weeks and months -- may enable reservoir operators to take more effective release decisions to improve the performance of their systems. In practice this might mean a more reliable water supply system, a more profitable hydropower plant or a more sustainable environmental release policy. To this end, climate indices, which represent the oscillation of the ocean-atmospheric system, might be gainfully employed within reservoir operating models that adapt the reservoir operation as a function of the climate condition. This study develops a Stochastic Dynamic Programming (SDP) approach that can incorporate climate indices using a Hidden Markov Model. The model simulates the climatic regime as a hidden state following a Markov chain, with the state transitions driven by variation in climatic indices, such as the Southern Oscillation Index. Time series analysis of recorded streamflow data reveals the parameters of separate autoregressive models that describe the inflow to the reservoir under three representative climate states ("normal", "wet", "dry"). These models then define inflow transition probabilities for use in a classic SDP approach. The key advantage of the Hidden Markov Model is that it allows conditioning the operating policy not only on the reservoir storage and the antecedent inflow, but also on the climate condition, thus potentially allowing adaptability to a broader range of climate conditions. In practice, the reservoir operator would effect a water release tailored to a specific climate state based on available teleconnection data and forecasts. The approach is demonstrated on the operation of a realistic, stylised water reservoir with carry-over capacity in South-East Australia. Here teleconnections relating

  5. Efficient Data Assimilation Tool For Real Time CO2 Reservoir Monitoring and Characterization

    Science.gov (United States)

    Li, J. Y.; Ambikasaran, S.; Kokkinaki, A.; Darve, E. F.; Kitanidis, P. K.

    2014-12-01

    Reservoir forecasting and management are increasingly relying on a data-driven approach, which involves data assimilation to calibrate and keep up to date the complex model of multi-phase flow and transport in the geologic formation and to evaluate its uncertainty using monitoring data of different types and temporal resolution. The numbers of unknowns and measurements are usually very large, which represents a major computational challenge. Kalman filter (KF), the archetypical recursive filter, provides the framework to assimilate reservoir monitoring data into a dynamic system but the cost of implementing the original algorithm to large systems is computationally prohibitive. In our work, we have developed several Kalman-filter based approaches that reduce the computational and storage cost of standard KF from O (m2) to O (m), where m is the number of unknowns, and have the potential to be applied to field-scale problems. HiKF, a linear filter based on the hierarchical matrix approach, takes advantage of the informative high-frequency data acquired quasi-continuously and uses a random-walk model in the state forecast step when the a state evolution model is unavailable. A more general-purpose nonlinear filter CSKF achieves computational efficiency by exploiting the fact that the state covariance matrix for most dynamical systems can be approximated adequately through a low-rank matrix, and it allows using a forward simulator as a black-box for nonlinear error propagation. We will demonstrate both methods using synthetic CO2 injection cases and compare with the standard ensemble Kalman filter (EnKF).

  6. Characterization of biocenosis in the storage-reservoirs of liquid radioactive wastes of 'Mayak' PA

    Energy Technology Data Exchange (ETDEWEB)

    Pryakhin, E.; Tryapitsina, G.; Andreyev, S.; Akleyev, A. [Urals Research Center for Radiation Medicine - URCRM (Russian Federation); Mokrov, Y.; Ivanov, I. [Mayak PA (Russian Federation)

    2014-07-01

    A number of storage-reservoirs of liquid radioactive wastes of 'Mayak' Production Association ('Mayak' PA) with different levels of radioactive contamination: reservoir R-17 ('Staroye Boloto'), reservoir R-9 (Lake Karachay), reservoirs of the Techa Cascade R-3 (Koksharov pond), R-4 (Metlinsky pond), R-10 and R-11 is located in Chelyabinsk Oblast (Russia). The operation of these reservoirs began in 1949-1964. Full-scale hydro-biological studies of these reservoirs were started in 2007. The research into the status of biocenosis of these storage reservoirs of liquid radioactive wastes of 'Mayak' PA was performed in 2007 - 2011. The status of biocenosis was evaluated in accordance with the status of following communities: bacterio-plankton, phytoplankton, zooplankton, zoo-benthos, macrophytes and ichthyofauna. The status of ecosystems was determined by radioactive and chemical contamination of water bodies. The results of hydro-biological investigations showed that no changes in the status of biota in reservoir R-11 were revealed as compared to the biological parameters of the water bodies of this geographical zone. In terms of biological parameters the status of the ecosystem of the reservoir R-11 is characterized by a sufficient biological diversity, and can be considered acceptable. The ecosystem of the reservoir R-10 maintains its functional integrity, although there were registered negative effects in the zoo-benthos community associated with the decrease in the parameters of the development of pelophylic mollusks that live at the bottom of the water body throughout the entire life cycle. In reservoir R-4 the parameters of the development of phytoplankton did not differ from those in Reservoirs R-11 and R-10; however, a significant reduction in the quantity of Cladocera and Copepoda was registered in the zooplankton community, while in the zoo-benthos there were no small mollusks that live aground throughout the entire life

  7. Bayesian inversion of seismic and electromagnetic data for marine gas reservoir characterization using multi-chain Markov chain Monte Carlo sampling

    Science.gov (United States)

    Ren, Huiying; Ray, Jaideep; Hou, Zhangshuan; Huang, Maoyi; Bao, Jie; Swiler, Laura

    2017-12-01

    In this study we developed an efficient Bayesian inversion framework for interpreting marine seismic Amplitude Versus Angle and Controlled-Source Electromagnetic data for marine reservoir characterization. The framework uses a multi-chain Markov-chain Monte Carlo sampler, which is a hybrid of DiffeRential Evolution Adaptive Metropolis and Adaptive Metropolis samplers. The inversion framework is tested by estimating reservoir-fluid saturations and porosity based on marine seismic and Controlled-Source Electromagnetic data. The multi-chain Markov-chain Monte Carlo is scalable in terms of the number of chains, and is useful for computationally demanding Bayesian model calibration in scientific and engineering problems. As a demonstration, the approach is used to efficiently and accurately estimate the porosity and saturations in a representative layered synthetic reservoir. The results indicate that the seismic Amplitude Versus Angle and Controlled-Source Electromagnetic joint inversion provides better estimation of reservoir saturations than the seismic Amplitude Versus Angle only inversion, especially for the parameters in deep layers. The performance of the inversion approach for various levels of noise in observational data was evaluated - reasonable estimates can be obtained with noise levels up to 25%. Sampling efficiency due to the use of multiple chains was also checked and was found to have almost linear scalability.

  8. Bayesian inversion of seismic and electromagnetic data for marine gas reservoir characterization using multi-chain Markov chain Monte Carlo sampling

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Huiying; Ray, Jaideep; Hou, Zhangshuan; Huang, Maoyi; Bao, Jie; Swiler, Laura

    2017-12-01

    In this study we developed an efficient Bayesian inversion framework for interpreting marine seismic amplitude versus angle (AVA) and controlled source electromagnetic (CSEM) data for marine reservoir characterization. The framework uses a multi-chain Markov-chain Monte Carlo (MCMC) sampler, which is a hybrid of DiffeRential Evolution Adaptive Metropolis (DREAM) and Adaptive Metropolis (AM) samplers. The inversion framework is tested by estimating reservoir-fluid saturations and porosity based on marine seismic and CSEM data. The multi-chain MCMC is scalable in terms of the number of chains, and is useful for computationally demanding Bayesian model calibration in scientific and engineering problems. As a demonstration, the approach is used to efficiently and accurately estimate the porosity and saturations in a representative layered synthetic reservoir. The results indicate that the seismic AVA and CSEM joint inversion provides better estimation of reservoir saturations than the seismic AVA-only inversion, especially for the parameters in deep layers. The performance of the inversion approach for various levels of noise in observational data was evaluated – reasonable estimates can be obtained with noise levels up to 25%. Sampling efficiency due to the use of multiple chains was also checked and was found to have almost linear scalability.

  9. A stochastic conflict resolution model for water quality management in reservoir river systems

    Science.gov (United States)

    Kerachian, Reza; Karamouz, Mohammad

    2007-04-01

    In this paper, optimal operating rules for water quality management in reservoir-river systems are developed using a methodology combining a water quality simulation model and a stochastic GA-based conflict resolution technique. As different decision-makers and stakeholders are involved in the water quality management in reservoir-river systems, a new stochastic form of the Nash bargaining theory is used to resolve the existing conflict of interests related to water supply to different demands, allocated water quality and waste load allocation in downstream river. The expected value of the Nash product is considered as the objective function of the model which can incorporate the inherent uncertainty of reservoir inflow. A water quality simulation model is also developed to simulate the thermal stratification cycle in the reservoir, the quality of releases from different outlets as well as the temporal and spatial variation of the pollutants in the downstream river. In this study, a Varying Chromosome Length Genetic Algorithm (VLGA), which has computational advantages comparing to other alternative models, is used. VLGA provides a good initial solution for Simple Genetic Algorithms and comparing to Stochastic Dynamic Programming (SDP) reduces the number of state transitions checked in each stage. The proposed model, which is called Stochastic Varying Chromosome Length Genetic Algorithm with water Quality constraints (SVLGAQ), is applied to the Ghomrud Reservoir-River system in the central part of Iran. The results show, the proposed model for reservoir operation and waste load allocation can reduce the salinity of the allocated water demands as well as the salinity build-up in the reservoir.

  10. Technical note: Cascade of submerged reservoirs as a rainfall-runoff model

    Science.gov (United States)

    Kurnatowski, Jacek

    2017-09-01

    The rainfall-runoff conceptual model as a cascade of submerged linear reservoirs with particular outflows depending on storages of adjoining reservoirs is developed. The model output contains different exponential functions with roots of Chebyshev polynomials of the first kind as exponents. The model is applied to instantaneous unit hydrograph (IUH) and recession curve problems and compared with the analogous results of the Nash cascade. A case study is performed on a basis of 46 recession periods. Obtained results show the usefulness of the model as an alternative concept to the Nash cascade.

  11. Dual permeability modeling of flow in a fractured geothermal reservoir

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.D.; Allman, D.W.

    1986-01-01

    A three dimensional fracture system synthesis and flow simulation has been developed to correlate drawdown characteristics measured in a geothermal well and to provide the basis for an analysis of tracer tests. A new dual permeability approach was developed which incorporates simulations at two levels to better represent a discrete fracture system within computer limitations. The first incorporates a discrete simulation of the largest fractures in the system plus distributed or representative element stimulation of the smaller fractures. The second determines the representative element properties by discrete simulation of the smaller fractures. The fracture system was synthesized from acoustic televiewer data on the orientation and separation of three distinct fracture sets, together with additional data from the literature. Lognormal and exponential distributions of fracture spacing and radius were studied with the exponential distribution providing more reasonable results. Hydraulic apertures were estimated as a function of distance from the model boundary to a constant head boundary. Mean values of 6.7, 101 and 46 ..mu..m were chosen as the most representative values for the three fracture sets. Recommendations are given for the additional fracture characterization needed to reduce the uncertainties in the model. 20 refs., 6 figs.

  12. Will building new reservoirs always help increase the water supply reliability? - insight from a modeling-based global study

    Science.gov (United States)

    Zhuang, Y.; Tian, F.; Yigzaw, W.; Hejazi, M. I.; Li, H. Y.; Turner, S. W. D.; Vernon, C. R.

    2017-12-01

    More and more reservoirs are being build or planned in order to help meet the increasing water demand all over the world. However, is building new reservoirs always helpful to water supply? To address this question, the river routing module of Global Change Assessment Model (GCAM) has been extended with a simple yet physical-based reservoir scheme accounting for irrigation, flood control and hydropower operations at each individual reservoir. The new GCAM river routing model has been applied over the global domain with the runoff inputs from the Variable Infiltration Capacity Model. The simulated streamflow is validated at 150 global river basins where the observed streamflow data are available. The model performance has been significantly improved at 77 basins and worsened at 35 basins. To facilitate the analysis of additional reservoir storage impacts at the basin level, a lumped version of GCAM reservoir model has been developed, representing a single lumped reservoir at each river basin which has the regulation capacity of all reservoir combined. A Sequent Peak Analysis is used to estimate how much additional reservoir storage is required to satisfy the current water demand. For basins with water deficit, the water supply reliability can be improved with additional storage. However, there is a threshold storage value at each basin beyond which the reliability stops increasing, suggesting that building new reservoirs will not help better relieve the water stress. Findings in the research can be helpful to the future planning and management of new reservoirs.

  13. Effects of gas types and models on optimized gas fuelling station reservoir's pressure

    Directory of Open Access Journals (Sweden)

    M. Farzaneh-Gord

    2013-06-01

    Full Text Available There are similar algorithms and infrastructure for storing gas fuels at CNG (Compressed Natural Gas and CHG (Compressed Hydrogen Gas fuelling stations. In these stations, the fuels are usually stored in the cascade storage system to utilize the stations more efficiently. The cascade storage system generally divides into three reservoirs, commonly termed low, medium and high-pressure reservoirs. The pressures within these reservoirs have huge effects on performance of the stations. In the current study, based on the laws of thermodynamics, conservation of mass and real/ideal gas assumptions, a theoretical analysis has been constructed to study the effects of gas types and models on performance of the stations. It is intended to determine the optimized reservoir pressures for these stations. The results reveal that the optimized pressure differs between the gas types. For ideal and real gas models in both stations (CNG and CHG, the optimized non-dimensional low pressure-reservoir pressure is found to be 0.22. The optimized non-dimensional medium-pressure reservoir pressure is the same for the stations, and equal to 0.58.

  14. Using outcrop data for geological well test modelling in fractured reservoirs

    NARCIS (Netherlands)

    Aljuboori, F.; Corbett, P.; Bisdom, K.; Bertotti, G.; Geiger, S.

    2015-01-01

    Outcrop fracture data sets can now be acquired with ever more accuracy using drone technology augmented by field observations. These models can be used to form realistic, deterministic models of fractured reservoirs. Fractured well test models are traditionally seen to be finite or infinite

  15. An Efficient Upscaling Procedure Based on Stokes-Brinkman Model and Discrete Fracture Network Method for Naturally Fractured Carbonate Karst Reservoirs

    KAUST Repository

    Qin, Guan

    2010-01-01

    Naturally-fractured carbonate karst reservoirs are characterized by various-sized solution caves that are connected via fracture networks at multiple scales. These complex geologic features can not be fully resolved in reservoir simulations due to the underlying uncertainty in geologic models and the large computational resource requirement. They also bring in multiple flow physics which adds to the modeling difficulties. It is thus necessary to develop a method to accurately represent the effect of caves, fractures and their interconnectivities in coarse-scale simulation models. In this paper, we present a procedure based on our previously proposed Stokes-Brinkman model (SPE 125593) and the discrete fracture network method for accurate and efficient upscaling of naturally fractured carbonate karst reservoirs.

  16. A Step Forward to Closing the Loop between Static and Dynamic Reservoir Modeling

    Directory of Open Access Journals (Sweden)

    Cancelliere M.

    2014-12-01

    Full Text Available The current trend for history matching is to find multiple calibrated models instead of a single set of model parameters that match the historical data. The advantage of several current workflows involving assisted history matching techniques, particularly those based on heuristic optimizers or direct search, is that they lead to a number of calibrated models that partially address the problem of the non-uniqueness of the solutions. The importance of achieving multiple solutions is that calibrated models can be used for a true quantification of the uncertainty affecting the production forecasts, which represent the basis for technical and economic risk analysis. In this paper, the importance of incorporating the geological uncertainties in a reservoir study is demonstrated. A workflow, which includes the analysis of the uncertainty associated with the facies distribution for a fluvial depositional environment in the calibration of the numerical dynamic models and, consequently, in the production forecast, is presented. The first step in the workflow was to generate a set of facies realizations starting from different conceptual models. After facies modeling, the petrophysical properties were assigned to the simulation domains. Then, each facies realization was calibrated separately by varying permeability and porosity fields. Data assimilation techniques were used to calibrate the models in a reasonable span of time. Results showed that even the adoption of a conceptual model for facies distribution clearly representative of the reservoir internal geometry might not guarantee reliable results in terms of production forecast. Furthermore, results also showed that realizations which seem fully acceptable after calibration were not representative of the true reservoir internal configuration and provided wrong production forecasts; conversely, realizations which did not show a good fit of the production data could reliably predict the reservoir

  17. Application of a statistical model for the assessment of environmental quality in neotropical semi-arid reservoirs.

    Science.gov (United States)

    de Lira Azevêdo, Evaldo; de Lucena Barbosa, José Etham; Viana, Leandro Gomes; Anacleto, Maria José Pinheiro; Callisto, Marcos; Molozzi, Joseline

    2017-02-01

    The aim of this study was to develop a statistical model to assess the environmental quality of reservoirs located in semi-arid region using metrics of anthropogenic disturbance, water quality variables, and benthic macroinvertebrate communities as indicators. The proposed model was applied to 60 sites located in three reservoirs in the Paraíba river basin, Brazilian semi-arid region. Collections were made in December 2011. In each site, we collected one sample of benthic macroinvertebrates and one water sample for the determination of physical and chemical parameters. Characterization of the landscape was made through application of 10 physical habitat protocols on each site for the collected information on disturbance and subsequent calculation of disturbance metrics. The results showed the formation of two groups: group 1, consisting of 16 minimally altered sites, and group 2, with 44 severely altered sites. The proposed statistical model was sensitive enough to detect changes. In the minimally altered group, the Chironomids Aedokritus and Fissimentum were dominant, indicating a higher environmental quality, while Coelotanypus and Chironomus were abundant in severely altered sites with lower environmental quality. The conservation and management of reservoirs in semi-arid regions should be intensified in view of the need to maintain the environmental quality of these ecosystems.

  18. Petroacoustic Modelling of Heterolithic Sandstone Reservoirs: A Novel Approach to Gassmann Modelling Incorporating Sedimentological Constraints and NMR Porosity data

    Science.gov (United States)

    Matthews, S.; Lovell, M.; Davies, S. J.; Pritchard, T.; Sirju, C.; Abdelkarim, A.

    2012-12-01

    Heterolithic or 'shaly' sandstone reservoirs constitute a significant proportion of hydrocarbon resources. Petroacoustic models (a combination of petrophysics and rock physics) enhance the ability to extract reservoir properties from seismic data, providing a connection between seismic and fine-scale rock properties. By incorporating sedimentological observations these models can be better constrained and improved. Petroacoustic modelling is complicated by the unpredictable effects of clay minerals and clay-sized particles on geophysical properties. Such effects are responsible for erroneous results when models developed for "clean" reservoirs - such as Gassmann's equation (Gassmann, 1951) - are applied to heterolithic sandstone reservoirs. Gassmann's equation is arguably the most popular petroacoustic modelling technique in the hydrocarbon industry and is used to model elastic effects of changing reservoir fluid saturations. Successful implementation of Gassmann's equation requires well-constrained drained rock frame properties, which in heterolithic sandstones are heavily influenced by reservoir sedimentology, particularly clay distribution. The prevalent approach to categorising clay distribution is based on the Thomas - Stieber model (Thomas & Stieber, 1975), this approach is inconsistent with current understanding of 'shaly sand' sedimentology and omits properties such as sorting and grain size. The novel approach presented here demonstrates that characterising reservoir sedimentology constitutes an important modelling phase. As well as incorporating sedimentological constraints, this novel approach also aims to improve drained frame moduli estimates through more careful consideration of Gassmann's model assumptions and limitations. A key assumption of Gassmann's equation is a pore space in total communication with movable fluids. This assumption is often violated by conventional applications in heterolithic sandstone reservoirs where effective porosity, which

  19. PEMODELAN DAERAH TANGKAPAN AIR WADUK KELILING DENGAN MODEL SWAT (Keliling Reservoir Catchment Area Modeling Using SWAT Model

    Directory of Open Access Journals (Sweden)

    Teuku Ferijal

    2015-05-01

    Full Text Available This study aimed to model watershed area of Keliling Reservoir using SWAT model. The reservoir is located in Aceh Besar District, Province of Aceh. The model was setup using 90m x 90m digital elevation model, land use data extracted from remote sensing data and soil characteristic obtained from laboratory analysis on soil samples. Model was calibrated using observed daily reservoir volume and the model performance was analyzed using RMSE-observations standard deviation ratio (RSR, Nash-Sutcliffe efficiency (NSE and percent bias (PBIAS. The model delineated the study area into 3,448 Ha having 13 subwatersheds and 76 land units (HRUs. The watershed is mostly covered by forest (53% and grassland (31%. The analysis revealed the 10 most sensitive parameters i.e. GW_DELAY, CN2, REVAPMN, ALPHA_BF, SOL_AWC, GW_REVAP, GWQMN, CH_K2 and ESCO. Model performances were categorized into very good for monthly reservoir volume with ENS 0.95, RSR 0.23, and PBIAS 2.97. The model performance decreased when it used to analyze daily reservoir inflow with ENS 0.55, RSR 0.67, and PBIAS 3.46. Keywords: Keliling Reservoir, SWAT, Watershed   ABSTRAK Penelitian ini bertujuan untuk untuk memodelkan daerah tangkapan air Waduk Keliling dengan menggunakan Model SWAT. Waduk Keliling terletak di Kabupaten Aceh Besar, Propinsi Aceh. Dalam penelitian ini Model SWAT dikembangkan berdasarkan data digital elevasi model resolusi 90 m x90 m, tata guna lahan yang diperoleh dari intepretasi citra satelit dan data soil dari hasil analisa sampel tanah yang diperoleh di daerah penelitian. Model dikalibrasi dengan data volume waduk dan kinerja model dianalisa menggunakan parameter rasio akar rata-rata kuadrat error dan standard deviasi observasi (RSR, efesiensi Nash-Sutcliffe (NSE dan persentase bias (PBIAS. Hasil deleniasi untuk daerah penelitian menghasilkan suatu DAS dengan luas 3,448 Ha dan memiliki 13 Sub DAS yang dikelompokkan menjadi 76 unit lahan. Sebagian besar wilayah study

  20. An Analysis Model for Water Cone Subsidence in Bottom Water Drive Reservoirs

    Science.gov (United States)

    Wang, Jianjun; Xu, Hui; Wu, Shucheng; Yang, Chao; Kong, lingxiao; Zeng, Baoquan; Xu, Haixia; Qu, Tailai

    2017-12-01

    Water coning in bottom water drive reservoirs, which will result in earlier water breakthrough, rapid increase in water cut and low recovery level, has drawn tremendous attention in petroleum engineering field. As one simple and effective method to inhibit bottom water coning, shut-in coning control is usually preferred in oilfield to control the water cone and furthermore to enhance economic performance. However, most of the water coning researchers just have been done on investigation of the coning behavior as it grows up, the reported studies for water cone subsidence are very scarce. The goal of this work is to present an analytical model for water cone subsidence to analyze the subsidence of water cone when the well shut in. Based on Dupuit critical oil production rate formula, an analytical model is developed to estimate the initial water cone shape at the point of critical drawdown. Then, with the initial water cone shape equation, we propose an analysis model for water cone subsidence in bottom water reservoir reservoirs. Model analysis and several sensitivity studies are conducted. This work presents accurate and fast analytical model to perform the water cone subsidence in bottom water drive reservoirs. To consider the recent interests in development of bottom drive reservoirs, our approach provides a promising technique for better understanding the subsidence of water cone.

  1. A Comparative Study between a Pseudo-Forward Equation (PFE and Intelligence Methods for the Characterization of the North Sea Reservoir

    Directory of Open Access Journals (Sweden)

    Saeed Mojeddifar

    2014-12-01

    Full Text Available This paper presents a comparative study between three versions of adaptive neuro-fuzzy inference system (ANFIS algorithms and a pseudo-forward equation (PFE to characterize the North Sea reservoir (F3 block based on seismic data. According to the statistical studies, four attributes (energy, envelope, spectral decomposition and similarity are known to be useful as fundamental attributes in porosity estimation. Different ANFIS models were constructed using three clustering methods of grid partitioning (GP, subtractive clustering method (SCM and fuzzy c-means clustering (FCM. An experimental equation, called PFE and based on similarity attributes, was also proposed to estimate porosity values of the reservoir. When the validation set derived from training wells was used, the R-square coefficient between two variables (actual and predicted values was obtained as 0.7935 and 0.7404 for the ANFIS algorithm and the PFE model, respectively. But when the testing set derived from testing wells was used, the same coefficients decreased to 0.252 and 0.5133 for the ANFIS algorithm and the PFE model, respectively. According to these results, and the geological characteristics observed in the F3 block, it seems that the ANFIS algorithms cannot estimate the porosity acceptably. By contrast, in the outputs of PFE, the ability to detect geological structures such as faults (gas chimney, folds (salt dome, and bright spots, alongside the porosity estimation of sandstone reservoirs, could help in determining the drilling target locations. Finally, this work proposes that the developed PFE could be a good technique for characterizing the reservoir of the F3 block.

  2. The HYDROMED model and its application to semi-arid Mediterranean catchments with hill reservoirs 3: Reservoir storage capacity and probability of failure model

    Directory of Open Access Journals (Sweden)

    R. Ragab

    2001-01-01

    Full Text Available This paper addresses the issue of "what reservoir storage capacity is required to maintain a yield with a given probability of failure?". It is an important issue in terms of construction and cost. HYDROMED offers a solution based on the modified Gould probability matrix method. This method has the advantage of sampling all years data without reference to the sequence and is therefore particularly suitable for catchments with patchy data. In the HYDROMED model, the probability of failure is calculated on a monthly basis. The model has been applied to the El-Gouazine catchment in Tunisia using a long rainfall record from Kairouan together with the estimated Hortonian runoff, class A pan evaporation data and estimated abstraction data. Generally, the probability of failure differed from winter to summer. Generally, the probability of failure approaches zero when the reservoir capacity is 500,000 m3. The 25% probability of failure (75% success is achieved with a reservoir capacity of 58,000 m3 in June and 95,000 m3 in January. The probability of failure for a 240,000 m3 capacity reservoir (closer to storage capacity of El-Gouazine 233,000 m3, is approximately 5% in November, December and January, 3% in March, and 1.1% in May and June. Consequently there is no high risk of El-Gouazine being unable to meet its requirements at a capacity of 233,000 m3. Subsequently the benefit, in terms of probability of failure, by increasing the reservoir volume of El-Gouazine to greater than the 250,000 m3 is not high. This is important for the design engineers and the funding organizations. However, the analysis is based on the existing water abstraction policy, absence of siltation rate data and on the assumption that the present climate will prevail during the lifetime of the reservoir. Should these conditions change, a new analysis should be carried out. Keywords: HYDROMED, reservoir, storage capacity, probability of failure, Mediterranean

  3. EOS simulation and GRNN modeling of the constant volume depletion behavior of gas condensate reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Elsharkawy, A.M.; Foda, S.G. [Kuwait University, Safat (Kuwait). Petroleum Engineering Dept.

    1998-03-01

    Currently, two approaches are being used to predict the changes in retrograde gas condensate composition and estimate the pressure depletion behavior of gas condensate reservoirs. The first approach uses the equation of states whereas the second uses empirical correlations. Equations of states (EOS) are poor predictive tools for complex hydrocarbon systems. The EOS needs adjustment against phase behavior data of reservoir fluid of known composition. The empirical correlation does not involve numerous numerical computations but their accuracy is limited. This study presents two general regression neural network (GRNN) models. The first model, GRNNM1, is developed to predict dew point pressure and gas compressibility at dew point using initial composition of numerous samples while the second model, GRNNM2, is developed to predict the changes in well stream effluent composition at any stages of pressure depletion. GRNNM2 can also be used to determine the initial reservoir fluid composition using dew point pressure, gas compressibility at dew point, and reservoir temperature. These models are based on analysis of 142 sample of laboratory studies of constant volume depletion (CVD) for gas condensate systems forming a total of 1082 depletion stages. The database represents a wide range of gas condensate systems obtained worldwide. The performance of the GRNN models has been compared to simulation results of the equation of state. The study shows that the proposed general regression neural network models are accurate, valid, and reliable. These models can be used to forecast CVD data needed for many reservoir engineering calculations in case laboratory data is unavailable. The GRNN models save computer time involved in EOS calculations. The study also show that once these models are properly trained they can be used to cut expenses of frequent sampling and laborious experimental CVD tests required for gas condensate reservoirs. 55 refs., 13 figs., 6 tabs.

  4. Characterization of In-Situ Stress and Permeability in Fractured Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Daniel R. Burns; M. Nafi Toksoz

    2006-06-30

    Fracture orientation and spacing are important parameters in reservoir development. This project resulted in the development and testing of a new method for estimating fracture orientation and two new methods for estimating fracture spacing from seismic data. The methods developed were successfully applied to field data from fractured carbonate reservoirs. Specific results include: the development a new method for estimating fracture orientation from scattered energy in seismic data; the development of two new methods for estimating fracture spacing from scattered energy in seismic data; the successful testing of these methods on numerical model data and field data from two fractured carbonate reservoirs; and the validation of fracture orientation results with borehole data from the two fields. Researchers developed a new method for determining the reflection and scattering characteristics of seismic energy from subsurface fractured formations. The method is based upon observations made from 3D finite difference modeling of the reflected and scattered seismic energy over discrete systems of vertical fractures. Regularly spaced, discrete vertical fractures impart a ringing coda type signature to seismic energy that is transmitted through or reflected off of them. This signature varies in amplitude and coherence as a function of several parameters including: (1) the difference in angle between the orientation of the fractures and the acquisition direction, (2) the fracture spacing, (3) the wavelength of the illuminating seismic energy, and (4) the compliance, or stiffness, of the fractures. This coda energy is the most coherent when the acquisition direction is parallel to the strike of the fractures. It has the largest amplitude when the seismic wavelengths are tuned to the fracture spacing, and when the fractures have low stiffness. The method uses surface seismic reflection traces to derive a transfer function that quantifies the change in the apparent source

  5. Thin-bed reservoir characterization using integrated three-dimensional seismic and well log data: A case study of the central Boonsville Field, Fort Worth basin, north-central Texas

    Science.gov (United States)

    Xie, Deyi

    This dissertation is designed to resolve two problems using seismic attributes to: (1) delineate thin-bed reservoirs, and (2) distinguish thin-bed sandstone reservoirs from thin-bed non-reservoir carbonates where they appear similar at seismic scale. I evaluated some widely used techniques, developed new approaches for better imaging of thin-bed reservoirs, and found optimal attributes for thin-bed reservoir characterization. These techniques were then tested on the Pennsylvanian Caddo sequence of the Boonsville Field, Texas using public domain data. The main results found through this study are: (1) A new pattern recognition model has been developed to recognize the subtle geological and geophysical features of a thin-bed sequence based on cross-correlation of seismic traces with one or more traces believed to represent specific depositional environments. This algorithm has been proven, via the case study, to be robust and promising in defining seismic facies for subtle geological features and predicting thin-bed reservoirs. (2) Examination of the conventional thin-bed tuning model reveals that it works well only if one single thin-bed is developed or multiple thin beds are widely spaced in the sequence of interest. In other words, the model does not work for multiple closely-spaced thin-beds because of significant destructive interference. (3) A statistical inversion method was developed using the generalized regression neural network (GRNN). For a comparison study, two commercial packages were applied to the Boonsville Field data set. This study shows that all three models were able to identify the thicker reservoir sandstones and non-reservoir limestones. However, the resulting details for the thin beds vary. The GRNN method predicted the thin beds at 13 out of 20 wells with less noise and can be very useful in detecting thin-bed reservoirs in existing fields where a number of wells are available.

  6. Diagenetic setting, dolomitization and reservoir characterization of Late Cretaceous Kawagarh Formation, Khanpur Dam section, Hazara, Pakistan

    Directory of Open Access Journals (Sweden)

    Maqsood Ur Rahman

    2016-12-01

    Full Text Available The Kawagarh Formation is well exposed in Hazara basin in different sections. Due to deep depositional settings, the Kawagarh Formation is least appealing to geologists to investigate it as a hydrocarbon reservoir. In the present study, the diagenetic settings of Kawagarh Formation were chronologically studied to interpret its diagenetic history and the effect of different diagenetic phases on the reservoir potential. The dolomitization is also studied in depth to use it as a key for its reservoir potential. Kawagarh Formation is sampled at Khanpur Dam Section for porosity analysis. The samples were taken from limestone and dolomite facies randomly. The dolomites are in the form of veins and well developed thick size beds. These dolomites are secondary in nature which is hosted by fractures and joints of limestone, which affect about 25% of limestone facies. At outcrop scale different types of dolomites are recognised on the basis of color and texture, yellowish fine-grained, brown blackish coarse-grained in the top portion and saddle dolomites. In petrographic study partial and complete dolomitization are observed. On the basis of crystal sizes and geometry different types of dolomites are recognized which are; (1 fine crystalline planar-euhedral dolomite, (2 medium crystalline planar-subhedral dolomite, (3 medium crystalline non-planar-anhedral dolomite, (4 coarse crystalline planar-subhedral dolomite, (5 coarse crystalline, non-planar-anhedral dolomite and (6 saddle dolomites (SD1. In petrographic study, high inclusions and disturbance are observed at the surfaces of dolomitic rhombs which indicate low Mg replacement or dedolomitization phenomena. On image J porosity analysis, the porosity is found of limestone and dolomitic samples. In limestone facies which is mostly, non-laminated mudstone has very low up to 2 to 3% in the form of vugs and fractures. In dolomitic facies, the porosity is ranging from 5% to 14%. In most of the dolomitic

  7. Facies analysis of an Upper Jurassic carbonate platform for geothermal reservoir characterization

    Science.gov (United States)

    von Hartmann, Hartwig; Buness, Hermann; Dussel, Michael

    2017-04-01

    objects, like lagoons or reefs and reef mounts. Faults within this area seem to be influenced by the facies distribution and otherwise, the deformation along the faults also depended on different lithologies. The reconstruction of the development of the carbonate platform can give hints also to erosional and karst processes. The results will be included into a numerical modelling of the geothermal reservoir to analyze the interaction of geothermal wells.

  8. Use of black oil simulator for coal bed methane reservoir model

    Energy Technology Data Exchange (ETDEWEB)

    Sonwa, R.; Enachescu, C.; Rohs, S. [Golder Associates GmbH, Celle (Germany)

    2013-08-01

    This paper starts from the work done by Seidle et al. (1990) and other authors on the topic of coal degasification and develops a more accurate representative naturally fractured CBM-reservoir by using a Discrete Fracture Network modeling approach. For this issue we firstly calibrate the reservoir simulator tNAVIGATOR by showing his ability to reproduce the work done by Seidle et al. and secondly generate a DFN model using FracMan in accordance with the distribution and orientation of the cleats. tNavigator was then used to simulate multiphase flow through the DFN- Model. (orig.)

  9. PVT characterization and viscosity modeling and prediction of crude oils

    DEFF Research Database (Denmark)

    Cisneros, Eduardo Salvador P.; Dalberg, Anders; Stenby, Erling Halfdan

    2004-01-01

    method based on an accurate description of the fluid mass distribution is presented. The characterization procedure accurately matches the fluid saturation pressure. Additionally, a Peneloux volume translation scheme, capable of accurately reproducing the fluid density above and below the saturation...... deliver accurate viscosity predictions. The modeling approach presented in this work can deliver accurate viscosity and density modeling and prediction results over wide ranges of reservoir conditions, including the compositional changes induced by recovery processes such as gas injection.......In previous works, the general, one-parameter friction theory (f-theory), models have been applied to the accurate viscosity modeling of reservoir fluids. As a base, the f-theory approach requires a compositional characterization procedure for the application of an equation of state (EOS), in most...

  10. Simulation and resistivity modeling of a geothermal reservoir with waters of different salinity

    Energy Technology Data Exchange (ETDEWEB)

    Pruess, K.; Wilt, M.; Bodvarsson, G.S.; Goldstein, N.E.

    1982-10-01

    Apparent resistivities measured by means of repetitive dipole-dipole surveys show significant changes within the Cerro Prieto reservoir. The changes are attributed to production and natural recharge. To better understand the observed geophysical phenomena a simple reservoir simulation study combined with the appropriate DC resistivity calculations to determine the expected magnitude of apparent resistivity change. We consider production from a liquid-dominated reservoir with dimensions and parameters of the Cerro Prieto A reservoir and assume lateral and vertical recharge of colder and less saline waters. Based on rather schematic one- and two-dimensional reservoir simulations, we calculate changes in formation resistivity which we then transform into changes in apparent resistivity that would be observed at the surface. Simulated changes in apparent resistivities over the production zone show increases of 10 to 20% over a 3 year period at the current rate of fluid extraction. Changes of this magnitude are not only within our ability to discern using proper field techniques, but are consistent in magnitude with some of the observed effects. However, the patterns of apparent resistivity changes in the simulated dipole-dipole pseudosection only partially resemble the observed field data. This is explained by the fact that the actual fluid recharge into the A reservoir is more complicated than assumed in our simple, schematic recharge models.

  11. Application of integrated reservoir management and reservoir characterization to optimize infill drilling. Quarterly technical progress report, September 13--December 12, 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    The eighteen 10-acre infill wells which were drilled as part of the field demonstration portion of the project are all currently in service with no operational problems. These wells consist of fourteen producing wells and four injection wells. The producing wells are currently producing a total of approximately 450 bopd, down from a peak rate of 900 bopd. Unit production is currently averaging approximately 2,700 bopd, 12,000 bwpd and 18,000 bwipd. The paper describes progress on hydraulic fracture design, reservoir surveillance, data analysis procedures, and deterministic modeling and simulation.

  12. Characterization of dynamic change of Fan-delta reservoir properties in water-drive development

    Energy Technology Data Exchange (ETDEWEB)

    Wu Shenghe; Xiong Qihua; Liu Yuhong [Univ. of Petroleum Changping, Beijing (China)

    1997-08-01

    Fan-delta reservoir in Huzhuangji oil field of east China, is a typical highly heterogeneous reservoir. The oil field has been developed by water-drive for 10 years, but the oil recovery is less than 12%, and water cut is over 90%, resulting from high heterogeneity and serious dynamic change of reservoir properties. This paper aims at the study of dynamic change of reservoir properties in water-drive development. Through quantitative imaging analysis and mercury injection analysis of cores from inspection wells, the dynamic change of reservoir pore structure in water-drive development was studied. The results show that the {open_quotes}large pore channels{close_quotes} develop in distributary channel sandstone and become larger in water-drive development, resulting in more serious pore heterogeneity. Through reservoir sensitivity experiments, the rock-fluid reaction in water-drive development is studied. The results show the permeability of some distal bar sandstone and deserted channel sandstone becomes lower due to swelling of I/S clay minerals in pore throats. OD the other hand, the permeability of distributary channel and mouth bar sandstone become larger because the authigenic Koalinites in pore throats are flushed away with the increase of flow rate of injection water. Well-logging analysis of flooded reservoirs are used to study the dynamic change of reservoir properties in various flow units. The distribution of remaining oil is closely related to the types and distribution of flow units.

  13. Continuous updating of a coupled reservoir-seismic model using an ensemble Kalman filter technique

    Energy Technology Data Exchange (ETDEWEB)

    Skjervheim, Jan-Arild

    2007-07-01

    This work presents the development of a method based on the ensemble Kalman filter (EnKF) for continuous reservoir model updating with respect to the combination of production data, 3D seismic data and time-lapse seismic data. The reservoir-seismic model system consists of a commercial reservoir simulator coupled to existing rock physics and seismic modelling software. The EnKF provides an ideal-setting for real time updating and prediction in reservoir simulation models, and has been applied to synthetic models and real field cases from the North Sea. In the EnKF method, static parameters as the porosity and permeability, and dynamic variables, as fluid saturations and pressure, are updated in the reservoir model at each step data become available. In addition, we have updated a lithology parameter (clay ratio) which is linked to the rock physics model, and the fracture density in a synthetic fractured reservoir. In the EnKF experiments we have assimilated various types of production and seismic data. Gas oil ratio (GOR), water cut (WCT) and bottom-hole pressure (BHP) are used in the data assimilation. Furthermore, inverted seismic data, such as Poisson's ratio and acoustic impedance, and seismic waveform data have been assimilated. In reservoir applications seismic data may introduce a large amount of data in the assimilation schemes, and the computational time becomes expensive. In this project efficient EnKF schemes are used to handle such large datasets, where challenging aspects such as the inversion of a large covariance matrix and potential loss of rank are considered. Time-lapse seismic data may be difficult to assimilate since they are time difference data, i.e. data which are related to the model variable at two or more time instances. Here we have presented a general sequential Bayesian formulation which incorporates time difference data, and we show that the posterior distribution includes both a filter and a smoother solution. Further, we show

  14. Characterization of dissolved and particulate natural organic matter (NOM) in Neversink Reservoir, New York

    Science.gov (United States)

    Wershaw, Robert L.; Leenheer, Jerry A.; Cox, Larry G.

    2005-01-01

    Natural organic matter (NOM) was isolated from the water of the Neversink Reservoir, part of the New York City water supply, located in the Catskill Mountains of New York. The NOM was fractionated into the following nine different fractions by the isolation procedure: (1) coarse particulates, (2) fine-particulate organics, (3) solvent-extractable organics, (4) hydrophobic neutrals (HPON fraction), (5) dissolved colloids, (6) bases, (7) hydrophobic acids (HPOA), (8) transphilic acids + neutrals (TPI-A+N), and (9) hydrophilic acids + neutrals (HPI-A+N). Each of these fractions, with exception of the first and the third which were too small for the complete series of analyses, was characterized by elemental, carbohydrate, and amino acid analyses, and by nuclear magnetic resonance and infrared spectrometry. The data obtained from these analyses indicate (1) that the fine-particulate organics and colloids are mainly composed of peptidoglycans, and lipopolysaccharides derived from algal, bacterial, and fungal cell walls, (2) that the HPO-N fraction most likely consists of a mixture of alicyclic terpenes and carbohydrates, (3) that the HPOA fraction consists mainly of lignin components conjugated to carbohydrates, (4) that the TPI-A+N and the HPI-A+N fractions most likely represent complex mixtures of relatively low molecular weight carboxylic acids derived from terpenes, carbohydrates, and peptides, and (5) that the base fraction is composed of free amino acids, browning reaction products, and peptide fragments.

  15. Characterization of the Human Pancreas Side Population as a Potential Reservoir of Adult Stem Cells.

    Science.gov (United States)

    Augstein, Petra; Loudovaris, Thomas; Bandala-Sanchez, Esther; Heinke, Peter; Naselli, Gaetano; Lee, Lily; Hawthorne, Wayne J; Góñez, L Jorge; Neale, Alana M; Vaillant, François; Thomas, Helen E; Kay, Thomas W; Banakh, Ilia; Harrison, Leonard C

    2018-01-01

    The side population (SP) contains cells with stem cell/progenitor properties. Previously, we observed that the mouse pancreas SP expanded after pancreatic injury. We aimed to characterize the SP in human pancreas as a potential source of stem cells. Human organ donor pancreata were fractionated into islets and exocrine tissue, enriched by tissue culture and dispersed into single cells. Cells were phenotyped by flow cytometry, and the SP was defined by efflux of fluorescent dye Hoechst 33342 visualized by ultraviolet excitation. Cells were flow sorted, and their colony-forming potential measured on feeder cells in culture. An SP was identified in islet and exocrine cells from human organ donors: 2 with type 1 diabetes, 3 with type 2 diabetes, and 28 without diabetes. Phenotyping revealed that exocrine SP cells had an epithelial origin, were enriched for carbohydrate antigen 19-9 ductal cells expressing stem cell markers CD133 and CD26, and had greater colony-forming potential than non-SP cells. The exocrine SP was increased in a young adult with type 1 diabetes and ongoing islet autoimmunity. The pancreatic exocrine SP is a potential reservoir of adult stem/progenitor cells, consistent with previous evidence that such cells are duct-derived and express CD133.

  16. Limnological characterization of the Itumbiara hydroelectric reservoir, Goiás, Brazil

    Directory of Open Access Journals (Sweden)

    José Luiz Stech

    2011-08-01

    Full Text Available The main objective of this work was to characterize the water properties of the Itumbaira, GO, hydroelectrically reservoir based on limnological and radiometric parameters. Two field campaigns were organized, the first during rainy (May and the second in the wet season (September. In these field campaigns, the following limnological parameters were analyzed: chlorophyll-a, dissolved organic and inorganic carbon, total suspended matter, water temperature, pH and turbidity. The radiometric data were taken using a FieldSpec Hand Held portable spectroradiometer. Also the absorption coefficient of the optically active components (OAC of the water were measured in laboratory. The limnological data was interpolated using Ordinary Kriging algorithm and the radiometric data were transformed in remote sensing reflectance. The absorption coefficient was used to build a triangular diagram designed to verify the relative contribution of the OAC in water. The results show that there was a distinct spatial variation in the limnology of the area affected by the dam and the one under the river confluences. Due to the low chlorophyll-a concentration in water, the spectral response was strongly influenced by inorganic suspended particles. The triangulation of the absorption coefficient revealed that the water is dominated by the inorganic particulate matter (from 65 to 80%. These results set the Itumbiara's water as case 2 water.

  17. Surface and Subsurface Geodesy Combined with Active Borehole Experimentation for the Advanced Characterization of EGS Reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Elsworth, Derek [Pennsylvania State Univ., University Park, PA (United States); Im, Kyungjae [Pennsylvania State Univ., University Park, PA (United States); Guglielmi, Yves [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mattioli, Glen [Univ. of Texas, Arlington, TX (United States). UNAVCO

    2016-11-14

    We explore the utility of combining active downhole experimentation with borehole and surface geodesy to determine both the characteristics and evolving state of EGS reservoirs during stimulation through production. The study is divided into two parts. We demonstrate the feasibility of determining in situ reservoir characteristics of reservoir size, strain and fracture permeability and their dependence on feedbacks of stress and temperature using surface and borehole geodetic measurements (Part I). We then define the opportunity to apply the unique hydraulic pulse protocol (HPP) borehole tool to evaluate reservoir state. This can be accomplished by monitoring and co-inverting measured reservoir characteristics (from the HPP tool) with surface geodetic measurements of deformation, tilt and strain with continuous measurements of borehole-wall strain (via optical fiber and fiber Bragg gratings) and measured flow rates (Part II).

  18. Rock Physics Modeling and Seismic Interpretation to Estimate Shally Cemented Zone in Carbonate Reservoir Rock

    Directory of Open Access Journals (Sweden)

    Handoyo Handoyo

    2016-12-01

    Full Text Available Carbonate rock are important hydrocarbon reservoir rocks with complex texture and petrophysical properties (porosity and permeability. These complexities make the prediction reservoir characteristics (e.g. porosity and permeability from their seismic properties more difficult. The goal of this paper are to understanding the relationship of physical properties and to see the signature carbonate initial rock and shally-carbonate rock from the reservoir. To understand the relationship between the seismic, petrophysical and geological properties, we used rock physics modeling from ultrasonic P- and S- wave velocity that measured from log data. The measurements obtained from carbonate reservoir field (gas production. X-ray diffraction and scanning electron microscope studies shown the reservoir rock are contain wackestone-packstone content. Effective medium theory to rock physics modeling are using Voigt, Reuss, and Hill.  It is shown the elastic moduly proposionally decrease with increasing porosity. Elastic properties and wave velocity are decreasing proporsionally with increasing porosity and shally cemented on the carbonate rock give higher elastic properties than initial carbonate non-cemented. Rock physics modeling can separated zones which rich of shale and less of shale.

  19. An Integrated Approach to Characterizing Bypassed Oil in Heterogeneous and Fractured Reservoirs Using Partitioning Tracers. Annual Report

    International Nuclear Information System (INIS)

    Akhil Datta-Gupta

    2006-01-01

    This report presents an efficient trajectory-based approach to integrate transient pressure data into high-resolution reservoir and aquifer models. The method involves alternating travel time and peak amplitude matching of pressure response using inverse modeling and is particularly well-suited for high resolution subsurface characterization using hydraulic tomography or pressure interference tests. Compared to travel time inversion only, our proposed approach results in a significantly improved match of the pressure response at the wells and also better estimates of subsurface properties. This is accomplished with very little increase in computational cost. Utilizing the concept of a ''diffusive'' time of flight derived from an asymptotic solution of the diffusivity equation, we develop analytical approaches to estimate the sensitivities for travel time and peak amplitude of pressure response to subsurface properties. The sensitivities are then used in an iterative least-squared minimization to match the pressure data. We illustrate our approach using synthetic and field examples. In the field application at a fractured limestone formation, the predominant fracture patterns emerging from the inversion are shown to be consistent with independent geophysical experiments and borehole data

  20. CHARACTERIZATION OF IN-SITU STRESS AND PERMEABILITY IN FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Daniel R. Burns; M. Nafi Toksoz

    2002-12-31

    We have extended a three-dimensional finite difference elastic wave propagation model previously developed at the Massachusetts Institute of Technology (MIT) Earth Resources Laboratory (ERL) for modeling and analyzing the effect of fractures on seismic waves. The code has been translated into C language and parallelized [using message passing interface (MPI)] to allow for larger models to be run on Linux PC computer clusters. We have also obtained another 3-D code from Lawrence Berkeley Laboratory, which we will use for verification of our ERL code results and also to run discrete fracture models. Testing of both codes is underway. We are working on a new finite difference model of borehole wave propagation for stressed formations. This code includes coordinate stretching to provide stable, variable grid sizes that will allow us to model the thin fluid annulus layers in borehole problems, especially for acoustic logging while drilling (LWD) applications. We are also extending our analysis routines for the inversion of flexural wave dispersion measurements for in situ stress estimates. Initial results on synthetic and limited field data are promising for a method to invert cross dipole data for the rotation angle and stress state simultaneously. A meeting is being scheduled between MIT and Shell Oil Company scientists to look at data from a fractured carbonate reservoir that may be made available to the project. The Focus/Disco seismic processing system from Paradigm Geophysical has been installed at ERL for field data analysis and as a platform for new analysis modules. We have begun to evaluate the flow properties of discrete fracture distributions through a simple 2D numerical model. Initial results illustrate how fluid flow pathways are very sensitive to variations in the geometry and apertures of fracture network.

  1. Stream, Lake, and Reservoir Management.

    Science.gov (United States)

    Dai, Jingjing; Mei, Ying; Chang, Chein-Chi

    2017-10-01

    This review on stream, lake, and reservoir management covers selected 2016 publications on the focus of the following sections: Stream, lake, and reservoir management • Water quality of stream, lake, and reservoirReservoir operations • Models of stream, lake, and reservoir • Remediation and restoration of stream, lake, and reservoir • Biota of stream, lake, and reservoir • Climate effect of stream, lake, and reservoir.

  2. Ground-Penetrating Radar and Dielectric Characterization of Shallow Reservoir Analogs in Central Texas Carbonates

    Science.gov (United States)

    Mukherjee, Damayanti; Heggy, Essam; Khan, Shuhab D.; Sullivan, Charlotte E.

    2007-10-01

    as a result of existing dielectric contrasts arising from a variation of moisture content and permeability. This effort characterizes shallow reservoir geometry and their dielectric heterogeneity in 3D, useful not only in hydrocarbon exploration in shallow realms but also in hydrological applications in carbonate terrains.

  3. Characterization of Tight Gas Reservoir Pore Structure Using USANS/SANS and Gas Adsorption Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Clarkson, Christopher R [ORNL; He, Lilin [ORNL; Agamalian, Michael [ORNL; Melnichenko, Yuri B [ORNL; Mastalerz, Maria [Indiana Geological Survey; Bustin, Mark [University of British Columbia, Vancouver; Radlinski, Andrzej Pawell [ORNL; Blach, Tomasz P [ORNL

    2012-01-01

    Small-angle and ultra-small-angle neutron scattering (SANS and USANS) measurements were performed on samples from the Triassic Montney tight gas reservoir in Western Canada in order to determine the applicability of these techniques for characterizing the full pore size spectrum and to gain insight into the nature of the pore structure and its control on permeability. The subject tight gas reservoir consists of a finely laminated siltstone sequence; extensive cementation and moderate clay content are the primary causes of low permeability. SANS/USANS experiments run at ambient pressure and temperature conditions on lithologically-diverse sub-samples of three core plugs demonstrated that a broad pore size distribution could be interpreted from the data. Two interpretation methods were used to evaluate total porosity, pore size distribution and surface area and the results were compared to independent estimates derived from helium porosimetry (connected porosity) and low-pressure N{sub 2} and CO{sub 2} adsorption (accessible surface area and pore size distribution). The pore structure of the three samples as interpreted from SANS/USANS is fairly uniform, with small differences in the small-pore range (< 2000 {angstrom}), possibly related to differences in degree of cementation, and mineralogy, in particular clay content. Total porosity interpreted from USANS/SANS is similar to (but systematically higher than) helium porosities measured on the whole core plug. Both methods were used to estimate the percentage of open porosity expressed here as a ratio of connected porosity, as established from helium adsorption, to the total porosity, as estimated from SANS/USANS techniques. Open porosity appears to control permeability (determined using pressure and pulse-decay techniques), with the highest permeability sample also having the highest percentage of open porosity. Surface area, as calculated from low-pressure N{sub 2} and CO{sub 2} adsorption, is significantly less

  4. Geological Model of Supercritical Geothermal Reservoir on the Top of the Magma Chamber

    Science.gov (United States)

    Tsuchiya, N.

    2017-12-01

    We are conducting supercritical geothermal project, and deep drilling project named as "JBBP: Japan Beyond Brittle Project" The temperatures of geothermal fields operating in Japan range from 200 to 300 °C (average 250 °C), and the depths range from 1000 to 2000 m (average 1500 m). In conventional geothermal reservoirs, the mechanical behavior of the rocks is presumed to be brittle, and convection of the hydrothermal fluid through existing network is the main method of circulation in the reservoir. In order to minimize induced seismicity, a rock mass that is "beyond brittle" is one possible candidate, because the rock mechanics of "beyond brittle" material is one of plastic deformation rather than brittle failure. To understand the geological model of a supercritical geothermal reservoir, granite-porphyry system, which had been formed in subduction zone, was investigated as a natural analog of the supercritical geothermal energy system. Quartz veins, hydrothermal breccia veins, and glassy veins are observed in a granitic body. The glassy veins formed at 500-550 °C under lithostatic pressures, and then pressures dropped drastically. The solubility of silica also dropped, resulting in formation of quartz veins under a hydrostatic pressure regime. Connections between the lithostatic and hydrostatic pressure regimes were key to the formation of the hydrothermal breccia veins, and the granite-porphyry system provides useful information for creation of fracture clouds in supercritical geothermal reservoirs. A granite-porphyry system, associated with hydrothermal activity and mineralization, provides a suitable natural analog for studying a deep-seated geothermal reservoir where stockwork fracture systems are created in the presence of supercritical geothermal fluids. I describe fracture networks and their formation mechanisms using petrology and fluid inclusion studies in order to understand this "beyond brittle" supercritical geothermal reservoir, and a geological

  5. Methods to evaluate some reservoir characterization by means of the geophysical data in the strata of limestone and marl

    Directory of Open Access Journals (Sweden)

    V. M. Seidov

    2017-12-01

    Full Text Available As we know, the main goal of interpreting the materials of well logging, including the allocation of collectors and assessment of their saturation, are successfully achieved when the process of interpretation has a strong methodological support. This means, that it is justified by the necessary interpretational models and effective instructional techniques are used. They are based on structural and petrophysical models of reservoirs of the section investigated. The problem of studying the marl rocks with the help of the geophysical methods is not worked out properly. Many years of experience of studying limestone and marl rocks has made it possible to justify the optimal method of data interpretation of geophysical research wells in carbonate sections, which was represented by limestone and marl formations. A new method was developed to study marl rocks. It includes the following main studies: detection of reservoirs in the carbonate section according to the materials of geophysical studies of wells; determination of the geophysical parameters of each reservoir; assessment of the quality of well logging curves; introduction of amendments; selection of reference layers; the calculation of the relative double differencing parameters; the involvement of core data; identifying the lithological rock composition; the rationale for structural models of reservoirs; the definition of the block and of the total porosity; determination of argillaceous carbonate rocks; determination of the coefficient of water saturation of formations based on the type of the collector; setting a critical value for effective porosity, etc. This method was applied in the Eocene deposits of the Interfluve of the Kura and Iori, which is a promising object of hydrocarbons in Azerbaijan. The following conclusions have been made: this methodology successfully solves the problem of petrophysical characteristics of marl rocks; bad connection is observed between some of the

  6. Modeling and Analysis of Integrated Bathymetric and Geodetic Data for Inventory Surveys of Mining Water Reservoirs

    Science.gov (United States)

    Ochałek, Agnieszka; Lipecki, Tomasz; Jaśkowski, Wojciech; Jabłoński, Mateusz

    2018-03-01

    The significant part of the hydrography is bathymetry, which is the empirical part of it. Bathymetry is the study of underwater depth of waterways and reservoirs, and graphic presentation of measured data in form of bathymetric maps, cross-sections and three-dimensional bottom models. The bathymetric measurements are based on using Global Positioning System and devices for hydrographic measurements - an echo sounder and a side sonar scanner. In this research authors focused on introducing the case of obtaining and processing the bathymetrical data, building numerical bottom models of two post-mining reclaimed water reservoirs: Dwudniaki Lake in Wierzchosławice and flooded quarry in Zabierzów. The report includes also analysing data from still operating mining water reservoirs located in Poland to depict how bathymetry can be used in mining industry. The significant issue is an integration of bathymetrical data and geodetic data from tachymetry, terrestrial laser scanning measurements.

  7. CHARACTERIZATION OF IN-SITU STRESS AND PERMEABILITY IN FRACTURED RESERVOIRS

    Energy Technology Data Exchange (ETDEWEB)

    Daniel R. Burns; M. Nafi Toksoz

    2004-07-19

    Expanded details and additional results are presented on two methods for estimating fracture orientation and density in subsurface reservoirs from scattered seismic wavefield signals. In the first, fracture density is estimated from the wavenumber spectra of the integrated amplitudes of the scattered waves as a function of offset in pre-stack data. Spectral peaks correctly identified the 50m, 35m, and 25m fracture spacings from numerical model data using a 40Hz source wavelet. The second method, referred to as the Transfer Function-Scattering Index Method, is based upon observations from 3D finite difference modeling that regularly spaced, discrete vertical fractures impart a ringing coda-type signature to any seismic energy that is transmitted through or reflected off of them. This coda energy is greatest when the acquisition direction is parallel to the fractures, the seismic wavelengths are tuned to the fracture spacing, and when the fractures have low stiffness. The method uses surface seismic reflection traces to derive a transfer function, which quantifies the change in an apparent source wavelet propagating through a fractured interval. The transfer function for an interval with low scattering will be more spike-like and temporally compact. The transfer function for an interval with high scattering will ring and be less temporally compact. A Scattering Index is developed based on a time lag weighting of the transfer function. When a 3D survey is acquired with a full range of azimuths, the Scattering Index allows the identification of subsurface areas with high fracturing and the orientation (or strike) of those fractures. The method was calibrated with model data and then applied to field data from a fractured reservoir giving results that agree with known field measurements. As an aid to understanding the scattered wavefield seen in finite difference models, a series of simple point scatterers was used to create synthetic seismic shot records collected over

  8. Virtual outcrop models of petroleum reservoir outcrop analogues – a review of the current state-of-the-art

    OpenAIRE

    Pringle, JK; Howell, JA; Hodgetts, D; Westerman, AR; Hodgson, DM

    2006-01-01

    A subsurface reservoir model is a computer based representation of petrophysical parameters such a porosity, permeability, fluid saturation, etc. Given that direct measurement of these parameters is limited to a few wells it is necessary to extrapolate their distribution. As geology is a first order control on petrophysics, it follows that an understanding of facies and their distribution is central to predicting reservoir quality and architecture. The majority of reservoir modelling systems ...

  9. Forecasting monthly inflow discharge of the Iffezheim reservoir using data-driven models

    Science.gov (United States)

    Zhang, Qing; Aljoumani, Basem; Hillebrand, Gudrun; Hoffmann, Thomas; Hinkelmann, Reinhard

    2017-04-01

    River stream flow is an essential element in hydrology study fields, especially for reservoir management, since it defines input into reservoirs. Forecasting this stream flow plays an important role in short or long-term planning and management in the reservoir, e.g. optimized reservoir and hydroelectric operation or agricultural irrigation. Highly accurate flow forecasting can significantly reduce economic losses and is always pursued by reservoir operators. Therefore, hydrologic time series forecasting has received tremendous attention of researchers. Many models have been proposed to improve the hydrological forecasting. Due to the fact that most natural phenomena occurring in environmental systems appear to behave in random or probabilistic ways, different cases may need a different methods to forecast the inflow and even a unique treatment to improve the forecast accuracy. The purpose of this study is to determine an appropriate model for forecasting monthly inflow to the Iffezheim reservoir in Germany, which is the last of the barrages in the Upper Rhine. Monthly time series of discharges, measured from 1946 to 2001 at the Plittersdorf station, which is located 6 km downstream of the Iffezheim reservoir, were applied. The accuracies of the used stochastic models - Fiering model and Auto-Regressive Integrated Moving Average models (ARIMA) are compared with Artificial Intelligence (AI) models - single Artificial Neural Network (ANN) and Wavelet ANN models (WANN). The Fiering model is a linear stochastic model and used for generating synthetic monthly data. The basic idea in modeling time series using ARIMA is to identify a simple model with as few model parameters as possible in order to provide a good statistical fit to the data. To identify and fit the ARIMA models, four phase approaches were used: identification, parameter estimation, diagnostic checking, and forecasting. An automatic selection criterion, such as the Akaike information criterion, is utilized

  10. Structural characterization and numerical simulations of flow properties of standard and reservoir carbonate rocks using micro-tomography

    Science.gov (United States)

    Islam, Amina; Chevalier, Sylvie; Sassi, Mohamed

    2018-04-01

    With advances in imaging techniques and computational power, Digital Rock Physics (DRP) is becoming an increasingly popular tool to characterize reservoir samples and determine their internal structure and flow properties. In this work, we present the details for imaging, segmentation, as well as numerical simulation of single-phase flow through a standard homogenous Silurian dolomite core plug sample as well as a heterogeneous sample from a carbonate reservoir. We develop a procedure that integrates experimental results into the segmentation step to calibrate the porosity. We also look into using two different numerical tools for the simulation; namely Avizo Fire Xlab Hydro that solves the Stokes' equations via the finite volume method and Palabos that solves the same equations using the Lattice Boltzmann Method. Representative Elementary Volume (REV) and isotropy studies are conducted on the two samples and we show how DRP can be a useful tool to characterize rock properties that are time consuming and costly to obtain experimentally.

  11. Understanding the Impact of Reservoir Operations on Temperature Hydrodynamics at Shasta Lake through 2D and 3D Modeling

    Science.gov (United States)

    Hallnan, R.; Busby, D.; Saito, L.; Daniels, M.; Danner, E.; Tyler, S.

    2016-12-01

    Stress on California's salmon fisheries as a result of recent drought highlights a need for effective temperature management in the Sacramento River. Cool temperatures are required for Chinook salmon spawning and rearing. At Shasta Dam in northern California, managers use selective reservoir withdrawals to meet downstream temperature thresholds set for Chinook salmon populations. Shasta Dam is equipped with a temperature control device (TCD) that allows for water withdrawals at different reservoir depths. A two-dimensional CE-QUAL-W2 (W2) model of Shasta Reservoir has been used to understand the impacts of TCD operations on reservoir and discharge dynamics at Shasta. W2 models the entire reservoir based on hydrologic and meteorological inputs, and therefore can be used to simulate various hydroclimatic conditions, reservoir operations, and resulting reservoir conditions. A limitation of the W2 model is that it only captures reservoir conditions in two dimensions (length and depth), which may not represent local hydrodynamic effects of TCD operations that could affect simulation of discharge temperatures. Thus, a three-dimensional (3D) model of the TCD and the immediately adjacent upstream reservoir has been constructed using computational fluid dynamics (CFD) in ANSYS Fluent. This 3D model provides additional insight into the mixing effects of different TCD operations, and resulting reservoir outflow temperatures. The drought conditions of 2015 provide a valuable dataset for assessing the efficacy of modeling the temperature profile of Shasta Reservoir under very low inflow volumes, so the W2 and CFD models are compared for model performance in late 2015. To assist with this assessment, data from a distributed temperature sensing (DTS) deployment at Shasta Lake since August 2015 are used. This presentation describes model results from both W2 as well as the CFD model runs during late 2015, and discuss their efficacy for modeling drought conditions.

  12. Modelling of water-gas-rock geo-chemical interactions. Application to mineral diagenesis in geological reservoirs

    International Nuclear Information System (INIS)

    Bildstein, Olivier

    1998-01-01

    Mineral diagenesis in tanks results from interactions between minerals, water, and possibly gases, over geological periods of time. The associated phenomena may have a crucial importance for reservoir characterization because of their impact on petrophysical properties. The objective of this research thesis is thus to develop a model which integrates geochemical functions necessary to simulate diagenetic reactions, and which is numerically efficient enough to perform the coupling with a transport model. After a recall of thermodynamic and kinetic backgrounds, the author discusses how the nature of available analytic and experimental data influenced choices made for the formalization of physical-chemical phenomena and for behaviour laws to be considered. Numerical and computational aspects are presented in the second part. The model is validated by using simple examples. The different possible steps during the kinetic competition between two mineral are highlighted, as well the competition between mineral reaction kinetics and water flow rate across the rock. Redox reactions are also considered. In the third part, the author reports the application of new model functions, and highlights the contribution of the modelling to the understanding of some complex geochemical phenomena and to the prediction of reservoir quality. The model is applied to several diagenetic transformations: cementation of dolomitic limestone by anhydride, illite precipitation, and thermal reduction of sulphates [fr

  13. Two Monthly Continuous Dynamic Model Based on Nash Bargaining Theory for Conflict Resolution in Reservoir System.

    Directory of Open Access Journals (Sweden)

    Mehran Homayounfar

    Full Text Available So far many optimization models based on Nash Bargaining Theory associated with reservoir operation have been developed. Most of them have aimed to provide practical and efficient solutions for water allocation in order to alleviate conflicts among water users. These models can be discussed from two viewpoints: (i having a discrete nature; and (ii working on an annual basis. Although discrete dynamic game models provide appropriate reservoir operator policies, their discretization of variables increases the run time and causes dimensionality problems. In this study, two monthly based non-discrete optimization models based on the Nash Bargaining Solution are developed for a reservoir system. In the first model, based on constrained state formulation, the first and second moments (mean and variance of the state variable (water level in the reservoir is calculated. Using moment equations as the constraint, the long-term utility of the reservoir manager and water users are optimized. The second model is a dynamic approach structured based on continuous state Markov decision models. The corresponding solution based on the collocation method is structured for a reservoir system. In this model, the reward function is defined based on the Nash Bargaining Solution. Indeed, it is used to yield equilibrium in every proper sub-game, thereby satisfying the Markov perfect equilibrium. Both approaches are applicable for water allocation in arid and semi-arid regions. A case study was carried out at the Zayandeh-Rud river basin located in central Iran to identify the effectiveness of the presented methods. The results are compared with the results of an annual form of dynamic game, a classical stochastic dynamic programming model (e.g. Bayesian Stochastic Dynamic Programming model, BSDP, and a discrete stochastic dynamic game model (PSDNG. By comparing the results of alternative methods, it is shown that both models are capable of tackling conflict issues in

  14. Two Monthly Continuous Dynamic Model Based on Nash Bargaining Theory for Conflict Resolution in Reservoir System.

    Science.gov (United States)

    Homayounfar, Mehran; Zomorodian, Mehdi; Martinez, Christopher J; Lai, Sai Hin

    2015-01-01

    So far many optimization models based on Nash Bargaining Theory associated with reservoir operation have been developed. Most of them have aimed to provide practical and efficient solutions for water allocation in order to alleviate conflicts among water users. These models can be discussed from two viewpoints: (i) having a discrete nature; and (ii) working on an annual basis. Although discrete dynamic game models provide appropriate reservoir operator policies, their discretization of variables increases the run time and causes dimensionality problems. In this study, two monthly based non-discrete optimization models based on the Nash Bargaining Solution are developed for a reservoir system. In the first model, based on constrained state formulation, the first and second moments (mean and variance) of the state variable (water level in the reservoir) is calculated. Using moment equations as the constraint, the long-term utility of the reservoir manager and water users are optimized. The second model is a dynamic approach structured based on continuous state Markov decision models. The corresponding solution based on the collocation method is structured for a reservoir system. In this model, the reward function is defined based on the Nash Bargaining Solution. Indeed, it is used to yield equilibrium in every proper sub-game, thereby satisfying the Markov perfect equilibrium. Both approaches are applicable for water allocation in arid and semi-arid regions. A case study was carried out at the Zayandeh-Rud river basin located in central Iran to identify the effectiveness of the presented methods. The results are compared with the results of an annual form of dynamic game, a classical stochastic dynamic programming model (e.g. Bayesian Stochastic Dynamic Programming model, BSDP), and a discrete stochastic dynamic game model (PSDNG). By comparing the results of alternative methods, it is shown that both models are capable of tackling conflict issues in water allocation

  15. Estimating the geographic distribution of human Tanapox and potential reservoirs using ecological niche modeling.

    Science.gov (United States)

    Monroe, Benjamin P; Nakazawa, Yoshinori J; Reynolds, Mary G; Carroll, Darin S

    2014-09-25

    Tanapox virus is a zoonotic infection that causes mild febrile illness and one to several nodular skin lesions. The disease is endemic in parts of Africa. The principal reservoir for the virus that causes Tanapox is unknown, but has been hypothesized to be a non-human primate. This study employs ecological niche modeling (ENM) to determine areas of tropical Africa suitable for the occurrence of human Tanapox and a list of hypothetical reservoirs. The resultant niche model will be a useful tool to guide medical surveillance activities in the region. This study uses the Desktop GARP software to predict regions where human Tanapox might be expected to occur based on historical human case locations and environmental data. Additional modeling of primate species, using occurrence data from museum records was performed to determine suitable disease reservoirs. The final ENM predicts a potential distribution of Tanapox over much of equatorial Africa, exceeding the borders of Kenya and Democratic Republic of Congo (DRC) where it has been historically reported. Five genera of non-human primates were found to be potential reservoir taxa. Validity testing suggests the model created here is robust (p modeling technique has several limitations and results should be interpreted with caution. This study may increase knowledge and engage further research in this neglected disease.

  16. A New Model to Predict Productivity of Multiple-Fractured Horizontal Well in Naturally Fractured Reservoirs

    Directory of Open Access Journals (Sweden)

    Junchao Wang

    2015-01-01

    Full Text Available In order to predict productivity of multiple-fractured horizontal well in fractured reservoir, flow models of reservoir and hydraulic fractures based on the volumetric source idealization are developed. The models are solved by utilizing Laplace transformation and orthogonal transformation, and flow rate of the well is calculated by coupling the two models. Compared to traditional point source functions, volumetric source function has many advantages in properties of function and programming calculation. The productivity predicting model is verified via an analytical ternary-porosity model. Moreover, a practical example of fractured horizontal well is studied to analyze the productivity and its influent factors. The result shows that flow rate of each fracture is different and inner fracture contributes least to productivity. Meanwhile, there are optimizing ranges for number, length, and conductivity of hydraulic fractures. In low-permeability reservoir, increasing surface area in contact with reservoir by increasing number and length of hydraulic fractures is the most effective method to improve the productivity.

  17. Modeling of Single and Dual Reservoir Porous Media Compressed Gas (Air and CO2) Storage Systems

    Science.gov (United States)

    Oldenburg, C. M.; Liu, H.; Borgia, A.; Pan, L.

    2017-12-01

    Intermittent renewable energy sources are causing increasing demand for energy storage. The deep subsurface offers promising opportunities for energy storage because it can safely contain high-pressure gases. Porous media compressed air energy storage (PM-CAES) is one approach, although the only facilities in operation are in caverns (C-CAES) rather than porous media. Just like in C-CAES, PM-CAES operates generally by injecting working gas (air) through well(s) into the reservoir compressing the cushion gas (existing air in the reservoir). During energy recovery, high-pressure air from the reservoir is mixed with fuel in a combustion turbine to produce electricity, thereby reducing compression costs. Unlike in C-CAES, the storage of energy in PM-CAES occurs variably across pressure gradients in the formation, while the solid grains of the matrix can release/store heat. Because air is the working gas, PM-CAES has fairly low thermal efficiency and low energy storage density. To improve the energy storage density, we have conceived and modeled a closed-loop two-reservoir compressed CO2 energy storage system. One reservoir is the low-pressure reservoir, and the other is the high-pressure reservoir. CO2 is cycled back and forth between reservoirs depending on whether energy needs to be stored or recovered. We have carried out thermodynamic and parametric analyses of the performance of an idealized two-reservoir CO2 energy storage system under supercritical and transcritical conditions for CO2 using a steady-state model. Results show that the transcritical compressed CO2 energy storage system has higher round-trip efficiency and exergy efficiency, and larger energy storage density than the supercritical compressed CO2 energy storage. However, the configuration of supercritical compressed CO2 energy storage is simpler, and the energy storage densities of the two systems are both higher than that of PM-CAES, which is advantageous in terms of storage volume for a given

  18. Reservoir monitoring and characterization using satellite geodetic data: Interferometric Synthetic Aperture Radar observations from the Krechba field, Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Vasco, D.W.; Ferretti, Alessandro; Novali, Fabrizio

    2008-05-01

    Deformation in the material overlying an active reservoir is used to monitor pressure change at depth. A sequence of pressure field estimates, eleven in all, allow us to construct a measure of diffusive travel time throughout the reservoir. The dense distribution of travel time values means that we can construct an exactly linear inverse problem for reservoir flow properties. Application to Interferometric Synthetic Aperture Radar (InSAR) data gathered over a CO{sub 2} injection in Algeria reveals pressure propagation along two northwest trending corridors. An inversion of the travel times indicates the existence of two northwest-trending high permeability zones. The high permeability features trend in the same direction as the regional fault and fracture zones. Model parameter resolution estimates indicate that the features are well resolved.

  19. Reservoir Characterization of Upper Devonian Gordon Sandstone, Jacksonburg, Stringtown Oil Field, Northwestern West Virginia

    Energy Technology Data Exchange (ETDEWEB)

    Ameri, S.; Aminian, K.; Avary, K.L.; Bilgesu, H.I.; Hohn, M.E.; McDowell, R.R.; Patchen, D.L.

    2002-05-21

    The purpose of this work was to establish relationships among permeability, geophysical and other data by integrating geologic, geophysical and engineering data into an interdisciplinary quantification of reservoir heterogeneity as it relates to production.

  20. Reservoir characterization using artificial neural network; Neural network wo mochiita choryuso tokusei kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Shimada, N.; Kozawa, T. [Japan National Oil Corp., Tokyo (Japan); Nishikawa, N.; Tani, A. [Fuji Research Institute Corp., Tokyo (Japan)

    1997-05-27

    Neural network is used for the prediction of porosity and permeability using logging data as reservoir characteristics, and the validity of this method is verified. For the prediction of reservoir characteristics by the use of seismic survey data, composite seismic survey records obtained by density logging and acoustic logging are used to experiment the prediction of porosity and permeability continuous along lines of wells. A 3-output back propagation network is used for analysis. There is a possibility that this technique when optimized will improve on prediction accuracy. Furthermore, in the case of characteristics mapping, 3-dimensional seismic data is applied to a carbonate rock reservoir for predicting spatial porosity and permeability. This technique facilitates the comprehensive analysis of core data, well data, and seismic survey data, enabling the derivation of a high-precision spatial distribution of reservoir characteristics. Efforts will continue for further improvement on prediction accuracy. 6 refs., 7 figs., 3 tabs.

  1. Quantifying Fracture Heterogeneity in Different Domains of Folded Carbonate Rocks to Improve Fractured Reservoir Analog Fluid Flow Models

    NARCIS (Netherlands)

    Bisdom, K.; Bertotti, G.; Gauthier, B.D.M.; Hardebol, N.J.

    2013-01-01

    Fluid flow in carbonate reservoirs is largely controlled by multiscale fracture networks. Significant variations of fracture network porosity and permeability are caused by the 3D heterogeneity of the fracture network characteristics, such as intensity, orientation and size. Characterizing fracture

  2. Modeling Alpine hydropower reservoirs management to study the water-energy nexus under change.

    Science.gov (United States)

    Castelletti, A.; Giuliani, M.; Fumagalli, E.; Weber, E.

    2014-12-01

    Climate change and growing population are expected to severely affect freshwater availability by the end of 21th century. Many river basins, especially in the Mediterranean region, are likely to become more prone to periods of reduced water supply, risking considerable impacts on the society, the environment, and the economy, thus emphasizing the need to rethink the way water resources are distributed, managed, and used at the regional and river basin scale. This paradigm shift will be essential to cope with the undergoing global change, characterized by growing water demands and by increasingly uncertain hydrologic regimes. Most of the literature traditionally focused on predicting the impacts of climate change on water resources, while our understanding of the human footprint on the hydrological cycle is limited. For example, changes in the operation of the Alpine hydropower reservoirs induced by socio-economic drivers (e.g., development of renewable energy) were already observed over the last few years and produced relevant impacts on multiple water uses due to the altered distribution of water volumes in time and space. Modeling human decisions as well as the links between society and environmental systems becomes key to develop reliable projections on the co-evolution of the coupled human-water systems and deliver robust adaptation strategies This work contributes a preliminary model-based analysis of the behaviour of hydropower operators under changing energy market and climate conditions. The proposed approach is developed for the San Giacomo-Cancano reservoir system, Italy. The identification of the current operating policy is supported by input variable selection methods to select the most relevant hydrological and market based drivers to explain the observed release time series.. The identified model is then simulated under a set of future scenarios, accounting for both climate and socio-economic change (e.g. expansion of the electric vehicle sector, load

  3. Field Characterization of Reservoir Flow Paths Using Miscible and Immiscible Tracer Tests

    OpenAIRE

    Trautz, Robert C.; Freifeld, Barry M.; Doughty, Christine; Benson, Sally M.; Phelps, Tommy J.; McCallum, Scott D.

    2005-01-01

    Injection of supercritical CO2 into deep, brine-filled reservoirs may be used to slow the effect that greenhouse gas emissions have on global warming. During injection, the large contrast in fluid densities and viscosities causes immiscible displacement of the brine by CO2, resulting in a two-phase system. We performed a series of tracer tests during the Frio CO2 sequestration pilot program to study immiscible and miscible fluid displacement through the Frio sandstone, a deep saline reservoir...

  4. Petrologic characteristic and Geological Model of Igneous Reservoir: An example in Zhanhua Seg, Eastern China

    Science.gov (United States)

    Li, Q.; Shao, S.; Kang, R.; Liu, K.

    2003-12-01

    The diabase is a typical igneous rock, which intrude the oil-bearing mudstone and form potential reservoir. As an example of Luo151 igneous rock in Zhanhua Seg, Eastern China, we studied the diabase reservoir in detail, including petrologic analysis, reservoir anisotropy and geological modeling. Four lithofacies zones are divided according to analyzing petrology, texture and structureϻwhich comprise carbonaceous slate, hornfels containing cordierite and grammite, border subfacies and central subfacies, and the petrologic types include carbonaceous slate, hornfels, and diabases. The diabase construction is divided into grammite hornfels micropore and diabase porous-fracture type reservoirs. The mudstone layers in Third Member of Shahejie Formation (Es3) provide favorable hydrocarbon source rock and cap formation, diabase and hornfels belts serve as reservoirs, faults and microcracks in the wall rocks as the pathways for oil and gas migration. The invasive time was about in the later deposition period of Dongying Formation and the middle of that of Guantao Formation, the oil generated from oil source rock of Es3 in the period of the Minghuazhen formation and is earlier more than the period of diabase oil trap and porous space forming.

  5. Superposition well-test method for reservoir characterization and pressure management during CO2 injection

    Science.gov (United States)

    White, J. A.

    2014-12-01

    As a significant fraction of a carbon storage project's budget is devoted to site characterization and monitoring, there has been an intense drive in recent years to both lower cost and improve the quality of data obtained. Two data streams that are cheap and always available are pressure and flow rate measurements from the injection well. Falloff testing, in which the well is shut-in for some period of time and the pressure decline curve measured, is often used to probe the storage zone and look for indications of hydraulic barriers, fracture-dominated flow, and other reservoir characteristics. These tests can be used to monitor many hydromechanical processes of interest, including hydraulic fracturing and fault reactivation. Unfortunately, the length of the shut-in period controls how far away from the injector information may be obtained. For operational reasons these tests are typically kept short and infrequent, limiting their usefulness. In this work, we present a new analysis method in which ongoing injection data is used to reconstruct an equivalent falloff test, without shutting in the well. The entire history of injection may therefore be used as a stand in for a very long test. The method relies upon a simple superposition principle to transform a multi-rate injection sequence into an equivalent single-rate process. We demonstrate the effectiveness of the method using injection data from the Snøhvit storage project. We also explore its utility in an active pressure management scenario. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  6. 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.

  7. Characterization of fracture reservoirs using static and dynamic data: From sonic and 3D seismic to permeability distribution

    Energy Technology Data Exchange (ETDEWEB)

    Parra, J.O.; Hackett, C.L.; Brown, R.L.; Collier, H.A.; Datta-Gupta, A.

    1998-10-01

    To characterize the Buena Vista Hills field, the authors have implemented methods of modeling, processing and interpretation. The modeling methods are based on deterministic and stochastic solutions. Deterministic solutions were developed in Phase 1 and applied in Phase 2 to simulate acoustic responses of laminated reservoirs. Specifically, the simulations were aimed at implementing processing techniques to correct P-wave and S-wave velocity logs for scattering effects caused by thin layering. The authors are also including a summary of the theory and the processing steps of this new method for predicting intrinsic dispersion and attenuation in Section 2. Since the objective for correcting velocity scattering effects is to predict intrinsic dispersion from velocity data, they are presenting an application to illustrate how to relate permeability anisotropy with intrinsic dispersion. Also, the theoretical solution for calculating full waveform dipole sonic that was developed in Phase 1 was applied to simulate dipole responses at different azimuthal source orientations. The results will be used to interpret the effects of anisotropy associated with the presence of vertical fractures at Buena Vista Hills. The results of the integration of core, well logs, and geology of Buena Vista Hills is also given in Section 2. The results of this integration will be considered as the input model for the inversion technique for processing production data. Section 3 summarizes accomplishments. In Section 4 the authors present a summary of the technology transfer and promotion efforts associated with this project. In the last section, they address the work to be done in the next six months and future work by applying the processing, modeling and inversion techniques developed in Phases 1 and 2 of this project.

  8. Numerical modeling of fracking fluid and methane migration through fault zones in shale gas reservoirs

    Science.gov (United States)

    Taherdangkoo, Reza; Tatomir, Alexandru; Sauter, Martin

    2017-04-01

    Hydraulic fracturing operation in shale gas reservoir has gained growing interest over the last few years. Groundwater contamination is one of the most important environmental concerns that have emerged surrounding shale gas development (Reagan et al., 2015). The potential impacts of hydraulic fracturing could be studied through the possible pathways for subsurface migration of contaminants towards overlying aquifers (Kissinger et al., 2013; Myers, 2012). The intent of this study is to investigate, by means of numerical simulation, two failure scenarios which are based on the presence of a fault zone that penetrates the full thickness of overburden and connect shale gas reservoir to aquifer. Scenario 1 addresses the potential transport of fracturing fluid from the shale into the subsurface. This scenario was modeled with COMSOL Multiphysics software. Scenario 2 deals with the leakage of methane from the reservoir into the overburden. The numerical modeling of this scenario was implemented in DuMux (free and open-source software), discrete fracture model (DFM) simulator (Tatomir, 2012). The modeling results are used to evaluate the influence of several important parameters (reservoir pressure, aquifer-reservoir separation thickness, fault zone inclination, porosity, permeability, etc.) that could affect the fluid transport through the fault zone. Furthermore, we determined the main transport mechanisms and circumstances in which would allow frack fluid or methane migrate through the fault zone into geological layers. The results show that presence of a conductive fault could reduce the contaminant travel time and a significant contaminant leakage, under certain hydraulic conditions, is most likely to occur. Bibliography Kissinger, A., Helmig, R., Ebigbo, A., Class, H., Lange, T., Sauter, M., Heitfeld, M., Klünker, J., Jahnke, W., 2013. Hydraulic fracturing in unconventional gas reservoirs: risks in the geological system, part 2. Environ Earth Sci 70, 3855

  9. ADVANCED CHARACTERIZATION OF FRACTURED RESERVOIRS IN CARBONATE ROCKS: THE MICHIGAN BASIN

    Energy Technology Data Exchange (ETDEWEB)

    James R. Wood; William B. Harrison

    2002-12-01

    Michigan Basin, and it is crucial in developing reservoir quality rocks in some fields. Data on the occurrence of dolomite was extracted from driller's reports for all reported occurrences in Michigan, nearly 50 fields and over 500 wells. A digital database was developed containing the geographic location of all these wells (latitude-longitude) as well as the elevation of the first encounter of dolomite in the field/reservoir. Analysis shows that these dolomite occurrences are largely confined to the center of the basin, but with some exceptions, such as N. Adams Field. Further, some of the dolomite occurrences show a definite relationship to the fracture pattern described above, suggesting a genetic relationship that needs further work. Other accomplishments of this past reporting period include obtaining a complete land grid for the State of Michigan and further processing of the high and medium resolution DEM files. We also have measured new fluid inclusion data on dolomites from several fields that suggest that the dolomitization occurred at temperatures between 100 and 150 C. Finally, we have extracted the lithologic data for about 5000 wells and are in the process of integrating this data into the overall model for the Michigan Basin.

  10. Reservoir creep and induced seismicity: inferences from geomechanical modeling of gas depletion in the Groningen field

    Science.gov (United States)

    van Wees, Jan-Diederik; Osinga, Sander; Van Thienen-Visser, Karin; Fokker, Peter A.

    2018-03-01

    The Groningen gas field in the Netherlands experienced an immediate reduction in seismic events in the year following a massive cut in production. This reduction is inconsistent with existing models of seismicity predictions adopting compaction strains as proxy, since reservoir creep would then result in a more gradual reduction of seismic events after a production stop. We argue that the discontinuity in seismic response relates to a physical discontinuity in stress loading rate on faults upon the arrest of pressure change. The stresses originate from a combination of the direct poroelastic effect through the pressure changes and the delayed effect of ongoing compaction after cessation of reservoir production. Both mechanisms need to be taken into account. To this end, we employed finite-element models in a workflow that couples Kelvin-Chain reservoir creep with a semi-analytical approach for the solution of slip and seismic moment from the predicted stress change. For ratios of final creep and elastic compaction up to 5, the model predicts that the cumulative seismic moment evolution after a production stop is subject to a very moderate increase, 2-10 times less than the values predicted by the alternative approaches using reservoir compaction strain as proxy. This is in agreement with the low seismicity in the central area of the Groningen field immediately after reduction in production. The geomechanical model findings support scope for mitigating induced seismicity through adjusting rates of pressure change by cutting down production.

  11. Model of erosion–landslide interaction in the context of the reservoir ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 122; Issue 6. Model of erosion–landslide interaction in the context of the reservoir water level variations (East Siberia, Russia): Factors, environment and mechanisms. Oksana Mazaeva Viktoria Khak Elena Kozyreva. Volume 122 Issue 6 December 2013 pp 1515- ...

  12. Study on detailed geological modelling for fluvial sandstone reservoir in Daqing oil field

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Hanqing; Fu Zhiguo; Lu Xiaoguang [Institute of Petroleum Exploration and Development, Daqing (China)

    1997-08-01

    Guided by the sedimentation theory and knowledge of modern and ancient fluvial deposition and utilizing the abundant information of sedimentary series, microfacies type and petrophysical parameters from well logging curves of close spaced thousands of wells located in a large area. A new method for establishing detailed sedimentation and permeability distribution models for fluvial reservoirs have been developed successfully. This study aimed at the geometry and internal architecture of sandbodies, in accordance to their hierarchical levels of heterogeneity and building up sedimentation and permeability distribution models of fluvial reservoirs, describing the reservoir heterogeneity on the light of the river sedimentary rules. The results and methods obtained in outcrop and modem sedimentation studies have successfully supported the study. Taking advantage of this method, the major producing layers (PI{sub 1-2}), which have been considered as heterogeneous and thick fluvial reservoirs extending widely in lateral are researched in detail. These layers are subdivided into single sedimentary units vertically and the microfacies are identified horizontally. Furthermore, a complex system is recognized according to their hierarchical levels from large to small, meander belt, single channel sandbody, meander scroll, point bar, and lateral accretion bodies of point bar. The achieved results improved the