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Results
Modelling Approach of Optimum and Effective Well Length Evaluation for MRC Development Strategy.
Shbair, Alaa Fadel (Adnoc Onshore) | Kherroubi, Djamal (Adnoc Onshore) | Bosivert, Ian (Halliburton) | Noordin, Firdaus Bin Mohamed (Adnoc Onshore) | Melo, Raphael (Melo Energy) | Abdalaziz, Khalid Mohammed (Melo Energy)
Abstract Maximum Reservoir Contact (MRC) drains have been introduced and implemented as an attractive solution in reservoir developments to accelerate production/injection while optimizing the development costs. The main objective of this paper is to provide a workflow to assess the optimum well length (Lopt) and MRC wells evaluation. In addition, it aims to highlight the factors affecting actual Effective well length (Leff) based on a study performed on a giant oil field and the planned execution plans to mitigate wells with poor effective well length. A new approach is proposed to predict the optimum well length based on the proportionality of flux rates and productivity index (PI). The approach uses steady-state well modelling packages built using the static well data such as trajectories, reservoir/fluid properties, vertical and lower completion tuned with dynamic data such as surface well test data and downhole P& T measurements. Output results are oil influx rates along the trajectory, PI and production profiles. For the sensitivities, an automated well model base calculation was implemented through an Excel-Macro to facilitate performing different realizations of wellbore design, permeability ranges, and tubing sizes. Next, the evaluation of horizontal wells was assessed utilizing surveillance tools with the integration of the several factors affecting the effective well length. Prior to implementing MRC drilling, the asset team must assess the optimum well length (Lopt) for their reservoir settings where a certain limit for horizontal section indicates an increase in frictional losses and increment (Q, PI) is no longer favorable. Theoretical models indicate productivity and rates proportionality with horizontal length. While field case evidence of wells surveillance show effective length is rarely 100%. The findings proved the tool's efficiency to predict Lopt with the capability to reduce simulation runs/efforts for multiple scenarios. For the studied reservoirs, the Lopt was inferred to be in the range of 9000 up to 16,000 ft depending on the permeability, fluid properties, completion size and surface back pressure. Tubing diameter size was found to have a major influence on the flux rate, while wellbore diameter had a negligible impact. The workflow assessment on field studies with average conventional wells and MRC wells length of 1800 ft-10,000 ft inferred significant factors affecting actual well effective length to be: Well placement (Porous/dense), Heel-toe effects, Damage while drilling, production/Injection rate, Barefoot vs. completion, acid Stimulation after drilling, Well accessibility due to hole condition and production rate limits (Spinner threshold). The tool will help in the preliminary assessment to decide the optimum well length for the MRC, considering the reservoir settings and multiple completion options. In addition, the application can be extended to integrate with dynamic simulation as a robust tool to optimize completion design to be fit for future conditions. Furthermore, the field case set a generic workflow for confirming factors that may impact the Leff and evaluate MRC performance.
- Asia > Middle East > UAE > Abu Dhabi > Rub' al Khali Basin > Bu Hasa Field > Thamama Group > Shuaiba Formation (0.98)
- Asia > Middle East > UAE > Abu Dhabi > Arabian Gulf > Rub' al Khali Basin > Abu Dhabi Field (0.97)
- Information Technology > Artificial Intelligence > Machine Learning > Supervised Learning (0.54)
- Information Technology > Artificial Intelligence > Machine Learning > Inductive Learning (0.54)
Embedding Physics and Data Driven Models for Smart Production Optimization. Field Examples
Mata, Carlos (ADNOC Upstream) | Badmaev, Dorzhi (ADNOC Upstream) | Saputelli, Luigi (ADNOC Upstream) | Mohan, Richard (ADNOC Upstream) | Rubio, Erismar (ADNOC Upstream) | Al Shehhi, Maha (ADNOC Upstream) | Salimov, Rail (ADNOC Upstream) | Eldjabri, Mamar (ADNOC Upstream)
Abstract The process of short-term water and gas flood optimization attempts to increase short term profit, while maximizing long term net present value (NPV) of the field. The characteristics of each production system would dictate how this process is achieved. Fields where the available producer well potential is significantly larger than the production quota could have infinite possible scenarios of production and injection well settings that would satisfy the field and reservoir production targets. But which of these scenarios maximize the long term NPV? This paper explains the framework being implemented in ADNOC to streamline the optimization workflow, which runs both physics and data driven models, honours all constraints, and covers the associated processes from model maintenance, to calculation, execution, and monitoring. The workflows are orchestrated with a series of in-house interconnected digital solutions. This framework has been implemented in 5 production systems undergoing pattern injection of water, gas, and CO2. The associated digital solutions are well adopted by the asset teams. Ability to optimize production and injection together has allowed the asset to focus on increasing injection capacity as the pattern, sector, and reservoir voidage constraints were identified to be the main constraint to production deliverability. The optimization scenario management and associated workflows have shown to deliver a gain of 1-3% of production by synchronizing the reservoir management process with the production operations business rhythm. The solutions have delivered so far more than 150 MM$ in value.
- North America > United States > Texas (0.46)
- Asia > Middle East > UAE > Abu Dhabi Emirate > Abu Dhabi (0.18)
- Energy > Oil & Gas > Upstream (1.00)
- Water & Waste Management > Water Management > Lifecycle > Disposal/Injection (0.34)
- Reservoir Description and Dynamics > Reservoir Simulation (1.00)
- Reservoir Description and Dynamics > Improved and Enhanced Recovery > Waterflooding (1.00)
- Reservoir Description and Dynamics > Improved and Enhanced Recovery > Gas-injection methods (1.00)
- (6 more...)
- Information Technology > Data Science (1.00)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Optimization (1.00)
Abstract Challenges in the design of efficient EOR field pilots have been discussed and documented in the industry, particularly when it comes to optimization of monitoring plans for technical and economical perspectives. This paper explores the benefits of pilot planning where the monitoring/control strategies are included in the early stages of the design to reduce risk of measurements ambiguity and ensure good quality pilot results evaluation. It addresses the use of new and existing technology in monitoring by highlighting the advantages and challenges of each alternative including potential pairing of complementary options to achieve the pilot objectives including illustration of the use of continuous and sporadic measurements on the evaluation. The proposed approach starts with a review of reservoir performance, heterogeneity and pilot objectives to ascertain the plausible monitoring technologies/strategies to aid during the pilot de-risking, followed by the identification of adequate novel and mature monitoring options, which are specific to EOR type and measurement nature (permanent, time lapse, etc.). Advantages of incorporating the monitoring strategy as integral part of the pilot design, as well as evaluation of the effectiveness/viability in the presence of uncertainty of the selected monitoring alternatives are discussed providing a reference of suitable/plausible EOR specific technologies. The paper illustrates the importance of selecting monitoring alternatives that feed off each other and the importance of using fit-for-purpose evaluation algorithms and a digitally enabled, structured approach to analyze and democratize pilot results and enable actionable decisions in operations.
- North America > United States (0.68)
- Europe > United Kingdom > North Sea > Central North Sea (0.24)
- Asia > Middle East > UAE > Abu Dhabi Emirate > Abu Dhabi (0.15)
- Geology > Geological Subdiscipline > Geomechanics (0.68)
- Geology > Rock Type > Sedimentary Rock (0.46)
- Geophysics > Borehole Geophysics (1.00)
- Geophysics > Time-Lapse Surveying > Time-Lapse Seismic Surveying (0.69)
- Geophysics > Seismic Surveying > Borehole Seismic Surveying (0.46)
- North America > United States > Texas > Permian Basin > Cogdell Field > Fuller Sand Formation (0.98)
- North America > United States > Texas > Permian Basin > Cogdell Field > Area Formation (0.98)
- Well Completion > Completion Monitoring Systems/Intelligent Wells (1.00)
- Reservoir Description and Dynamics > Reservoir Simulation (1.00)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (1.00)
- (20 more...)
- Information Technology > Sensing and Signal Processing (0.93)
- Information Technology > Architecture > Real Time Systems (0.68)
- Information Technology > Communications > Networks (0.46)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Uncertainty (0.34)
An Integrated Approach to Characterize Geological Features and Improve History Match of Water Movement Behavior in Giant Offshore Carbonate Reservoir
Qi, Zili (ADNOC Offshore) | AlZinati, Osama (ADNOC Offshore) | Almurshidi, Saja (ADNOC Offshore) | Copa, Cordell (ADNOC Offshore) | Alzaabi, Noura (ADNOC Offshore) | AlDhanhani, Helal (ADNOC Offshore) | AlNeyadi, Abdulla (ADNOC Offshore) | Fazal, Ayub (ADNOC Offshore)
Abstract In the subject reservoir, geological features (high perm streaks and fractures) are the key performance drivers that affect injected water movement behavior. However the horizontal and vertical distribution of these features have high uncertainties and it is very challenging to accurately capture these features and map into model. Here we developed one workflow to capture these features by integrating different sources of solid data, from core, open-hole resistivity log, PLT, well testing, production and surveillance data, etc. This reservoir has been on production for decades and plenty of static and dynamic data were acquired for the whole field. Among those data, conventional core analysis (CCAL), log derived k-PHIE regression, and well testing will measure reservoir permeability values, which could give guidance to the areal distribution of high perm and low perm regions. Afterwards, the difference between well test interpreted perm and CCAL measured perm could give some indication of some geological features (HKS, fractures, etc.) existing or not. Furthermore, these geological features could be further confirmed by the dynamic data, such as open-hole resistivity logs, PLT, and well production performance data, etc. After confirmation, those preliminary geological features will be mapped into static and simulation models, and the seamless geo-engineering loop of history match process will proceed until the final history match stage without compromising geologic plausibility and consistency. Going through the above integration workflow, the history match process was completed and the final history matched simulation model gives very promising water saturation match quality in both horizontal and vertical directions. In the horizontal direction, โผ90% of the producers get water cut match (trend and magnitude, dWC<5%), and also for recent drilled long horizontal producers (maximum reservoir contact (MRC) wells), model production profiles and water entry points along the laterals have good alignment with PLT and open-hole resistivity log data. In the vertical direction, model water saturation profiles have good alignment with open-hole resistivity log trend for hundreds of wells (โผ90% matched). PLT and WFL also have very good match quality. In general this simulation model could reproduce water movement very well in three dimensions using this new integration workflow, with much improvement compared to current the model. It gives higher confidence in the model predictive capacity, and the future field development plan will be studied using this New Generation Model Based on this integrated approach, a more plausible and consistent set of geological features are mapped and thus achieve promising history match quality of water movement with minimum local modifications, and thus enhance the model predictive capacity and provide better support of the life cycle field development.
- Well Drilling > Drilling Operations > Directional drilling (1.00)
- Reservoir Description and Dynamics > Reservoir Simulation > History matching (1.00)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (1.00)
- (5 more...)
Improved Integrated Approach in Reservoir Modeling by the Example of the Astokh Field
Pavlov, Dmitry (Sakhalin Energy Investment Company Ltd.) | Fedorov, Nikolay (Sakhalin Energy Investment Company Ltd.) | Timofeeva, Olga (Sakhalin Energy Investment Company Ltd.) | Vasiliev, Anton (Sakhalin Energy Investment Company Ltd.)
Abstract This paper summarizes the results of 3 years collaborative efforts of the Geophysicist, Production Geologist and Reservoir Engineers from the Astokh Development Team and the Geochemist from the LNG plant laboratory on integration of reservoir surveillance and reservoir modelling. In period 2015 - 2018 a large bulk of geological and field development data was collected in the Astokh field, in particular: cased and open hole logs, core, open hole pressure measurements, flowing and closed-in bottom hole pressures, well tests, new 4D seismic surveys (2015, 2018), fluid samples. Since 2016, essential progress was made in oil fingerprinting for oil production allocation. Simultaneously, the need for update of static and dynamic models was matured upon gaining experience in dynamic model history matching to field operational data (rates, pressures, results of well interventions). In other words, the need in update of geological architecture of the Astokh reservoir model was matured upon reaching critical mass of new data and experience. To revise well correlation, it was decided to combine different sorts of data, e.g. seismic, well logs and core data, reservoir pressures and oil fingerprinting. Different pressure regimes were identified for 3 layers within XXI reservoir. Pressure transient surveys were used for identification of geological boundaries where it's possible and this data was also incorporated into the model. Oil fingerprinting data was used for identification of different layers and compartments. Integration of pressure and oil geochemistry data allowed to identify inter-reservoir cross-flows caused by pressure differential. Based on all collected data, depositional model and reservoir correlation were updated based on sequential stratigraphy principles. As a result, a new static model of the main Astokh reservoirs was built, incorporating clinoform architecture for layers XXI-1โ and XXI-2. To check a new concept of geological architecture, material balance model was built and matched to the field data Integration of geological and field operational data provided a key to more advanced reservoir management and development strategy optimization. Based on updated reservoir model, new potential drilling targets were identified. Also, with new wells correlation, water flood optimization via management of voidage replacement ratio was proposed. The completed work suggests the essential improvement of reservoir modelling process by inclusion of the various well and reservoir surveillance data. This paper consists of the following sections: Introduction โย Field geology โย Field development history Scope of work complete and main results โย Proposed well logs correlation update for XXI-1โ and XXI-2 layers โชย Integration of well logs, pressure and fluid analysis data โย Connectivity between layers XXI-S, XXI-1โ and XXI-2 โชย Integration of pressure and oil fingerprinting data โย Connectivity within layers XXI-S, XXI-1โ and XXI-2 โชย Results of pressure interference tests โย Testing of new well correlation concept in material balance model โย Proposed reservoir correlation based on seismic data โย New geological concept โชย New depositional model โชย Integration of core data โชย Changes in reservoir architecture Conclusion โย Main results and impact on field development
- Asia > Russia (0.47)
- Asia > Middle East > UAE (0.28)
- Overview > Innovation (0.48)
- Research Report > Experimental Study (0.34)
- Geology > Geological Subdiscipline > Stratigraphy > Sequence Stratigraphy (1.00)
- Geology > Geological Subdiscipline > Geochemistry (1.00)
- Geology > Sedimentary Geology > Depositional Environment (0.93)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock (0.69)
- Geophysics > Borehole Geophysics (1.00)
- Geophysics > Seismic Surveying > Seismic Processing (0.68)
- Geophysics > Seismic Surveying > Seismic Interpretation (0.47)
- Reservoir Description and Dynamics > Reservoir Simulation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Seismic processing and interpretation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization > Geologic modeling (1.00)
- (5 more...)
Abstract Reservoir A is being developed in early and interim phases in order to gather static & dynamic data to minimize the risk associated to subsurface uncertainties. In early and interim phases, only production is taking places. During full field, water injection scheme will be implemented using mainly 5-spot pattern. It is very crucial to measure the subsurface uncertainties and their impact on the reservoir development. For this purpose, the uncertainty parameters are identified and their ranges are selected based on the current well performances during probabilistic History matching (PHM) phase. In full field runs, the uncertain subsurface parameters are quantified to prioritize the future reservoir monitoring and data gathering plans. Note that wells are equipped with the permanent downhole pressure gauges. Reservoir A is one of the major reservoirs of a green-field located offshore Abu Dhabi and is being developed with a 5-spot water injection pattern. The producers and water injectors are horizontal wells which are drilled across different flow unit within the reservoir. The reservoir properties are variable across all the flow units, which may results in a non-uniform water front. Being a green field, there are more uncertainties as compared to the brown field. More than three years production & pressure data is available which is used in this uncertainty study. This production data is mainly used to achieve the probabilistic History match on well-wise basis. In this uncertainty study, previous HM parameters are removed. However, based on previous history matching learnings, the subsurface uncertain parameters ranges are selected for this probabilistic History match phase. The criteria for filtering the valid runs during this phase are set to be ยฑ150 Psi compared to the actual downhole pressure readings. In case of decreasing this filtering range to 75 Psi, results in reduction in the reserve range in P90 to P10. Based on ยฑ150 Psi principle, the subsurface parameter ranges are furthered reformed for full field uncertainty study/run. The industry standard workflow is followed to quantify the subsurface parameters during this phase. In this study, we used the Permeability modifiers based on RRT, Faults transmisibilities, Relative Perm curves (based on SCAL data), Kv/Kh ratio (from PTA), etc. as uncertain parameters. The impact of each parameter is measured and quantified with respect to plateau and total reserves.
- Reservoir Description and Dynamics > Reservoir Simulation > Evaluation of uncertainties (1.00)
- Reservoir Description and Dynamics > Improved and Enhanced Recovery > Waterflooding (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Core analysis (1.00)
- Production and Well Operations > Well & Reservoir Surveillance and Monitoring (1.00)
Abstract The field of data-driven analytics and machine learning is rapidly evolving today and slowly beginning to reshape the petroleum sector with transformative initiatives. This work describes a heuristic approach combining mathematical modeling and associated data-driven workflows for estimating reservoir pressure surfaces through space and time using measured data. This procedure has been implemented successfully in a giant offshore field with a complex history of active pressure management by water and gas. This practical workflow generates present-day pressure maps that can be used directly in reservoir management by locating poorly supported areas and planning for mitigation activities. It assists and guides the history matching process by offering a benchmark against which simulated pressures can be compared. Combined with data-based streamlines computation, this workflow improves the understanding of fluid flow movements, help to identify baffles and assists in field sectorization. The distinctive feature of this data-driven approach is the unbiased reliance on field-observed data that complements complex modeling and compute-intensive schemes typically found in reservoir simulation. Conventional dynamic simulation and the tracing of streamlines require adequate static (e.g. permeability tensor) and dynamic models (e.g. pressures for each active cell in the system). Alternatively data-driven streamlines are readily available and calibrated. This paper presents innovative algorithms and workflows to the relatively limited existing body of literature on data-driven methods for pressure mapping. In this case study, new insights are effectively revealed such as inter-reservoir communication, enabled a better understanding of the gas movement and supported the change in production strategy. The paper is organized as follow. After a general overview of the field studied, this paper describes in detail the workflows used to interpolate pressures in space and time along with cross-validation results. Various applications of the pressure predictions are presented in the sections thereafter.
- Reservoir Description and Dynamics > Improved and Enhanced Recovery > Waterflooding (1.00)
- Production and Well Operations > Well & Reservoir Surveillance and Monitoring (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Drillstem/well testing (0.90)
- (4 more...)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Spatial Reasoning (0.50)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Temporal Reasoning (0.50)
- Information Technology > Artificial Intelligence > Machine Learning > Performance Analysis (0.34)
Novel Method for Consistent Initialization of Reservoir Simulation Models with Oil/Water Paleo-Contacts
Patacchini, Leonardo (Abu Dhabi Marine Operating Company) | Mohmed, Farzeen (Abu Dhabi Marine Operating Company) | Lavenu, Arthur P. (Abu Dhabi Marine Operating Company) | Ouzzane, Djamel (Abu Dhabi Marine Operating Company) | Hinkley, Richard (Halliburton) | Crockett, Steven (Halliburton) | Bedewi, Mahmoud (Halliburton)
Abstract The classic method for initializing reservoir simulation models in the presence of a transition zone, based on primary drainage capillary-gravity equilibrium, is extended to account for partial reimbibition post oil migration. This tackles situations where structural events, such as trap tilting or caprock leakage, caused the current free-water level (FWL) to rise above deeper paleo-contacts. A preliminary primary drainage initialization is performed with zero capillary pressure at the paleo (or deepest historical) FWL, to obtain a minimum historical water saturation distribution. From a capillary pressure hysteresis model, it is then possible to determine the appropriate imbibition scanning curve for each gridblock, which are used to perform a second initialization with zero capillary pressure at the current FWL. With the proposed method, log-derived saturation profiles can be honored using a physically meaningful capillary pressure model. Furthermore, when relative permeability hysteresis is active, it is possible as a byproduct of the initialization to assign the correct scanning curves at time zero to each gridblock, which ensures that initial phase mobilities (hence reservoir productivity) and residual oil saturation (hence recoverable oil to waterflood) are modeled correctly. This is demonstrated with a synthetic vertical 1D model. The method was implemented in a commercial reservoir simulator to support modeling work for a giant undeveloped carbonate reservoir, where available data suggest that more than 3/4 of the initial oil in place could be located between the current FWL and a dome-shaped paleo-FWL. This work is used as a case study to illustrate the elegance of the proposed method in the presence of multiple (or tilted) paleo-FWLs, as only one set of capillary pressure curves per dynamic rock-type is required to honor the complex log-derived saturation distribution.
- South America (0.68)
- Europe > Denmark > North Sea (0.46)
- North America > United States > Texas (0.28)
- Asia > Middle East > UAE > Abu Dhabi Emirate > Abu Dhabi (0.16)
- Geology > Structural Geology > Tectonics (0.94)
- Geology > Rock Type (0.67)
- Europe > Denmark > North Sea > Danish Sector > Central Graben > Block 5604/29 > South Arne Field (0.99)
- Asia > Middle East > Saudi Arabia > Thamama Group > Habshan Formation (0.99)
- Asia > Middle East > UAE > Abu Dhabi > Arabian Gulf > Rub' al Khali Basin > Abu Dhabi Field (0.97)
- Reservoir Description and Dynamics > Reservoir Simulation (1.00)
- Reservoir Description and Dynamics > Reservoir Fluid Dynamics > Flow in porous media (1.00)
- Reservoir Description and Dynamics > Reserves Evaluation > Estimates of resource in place (1.00)
- (2 more...)
Evolution of Reservoir Management and Development Strategy of a Giant Offshore Field in Abu Dhabi
Khan, Muhammad Navaid (Abdalla Abed Abu Dhabi Marine Operating Company) | Al Neaimi, Ahmed (Abdalla Abed Abu Dhabi Marine Operating Company) | Al-Shehhi, Omar (Abdalla Abed Abu Dhabi Marine Operating Company) | Channa, Zohaib (Abdalla Abed Abu Dhabi Marine Operating Company) | Ahmed, Fazeel (Abdalla Abed Abu Dhabi Marine Operating Company) | Al Feky, Mohamed (Abdalla Abed Abu Dhabi Marine Operating Company) | Sarsekov, Arlen (Abdalla Abed Abu Dhabi Marine Operating Company)
Abstract Reservoir management has been defined in many different ways, such as, "a sequence of resourceโdeployment decisions made to maintain optimum economic recovery of petroleum", "the application of available technology and knowledge to a reservoir system in order to control operations and maximize economic recovery within given management environment", "rely on use of financial, technological, and human resources, while minimizing capital investments and operating expenses to maximize economic recovery of oil and gas from a reservoir" (Thakur 1996) etc. Overall, the whole purpose of reservoir management is to help oil companies make the best decisions to meet specific objective using all the available resources. Essentially a reservoir management & development strategy is comprised of various elements; however, the purpose of this work is to shed light at the key elements, which were recently revisited to tackle the evolving changes in reservoir conditions for a giant Abu Dhabi Field, with a development and production history of over 50 years. The intent on this paper is to share the unique methodology adopted to address the sector-based reservoir performance and to generate the relevant opportunities to tackle the pertaining issues.
- Well Completion > Completion Installation and Operations (1.00)
- Reservoir Description and Dynamics > Reservoir Simulation (1.00)
- Reservoir Description and Dynamics > Reservoir Characterization (1.00)
- (8 more...)
Modeling of Hydrocarbons Below Free Water Level in a Major Oil Field in Abu Dhabi UAE and its Impacts on Dynamic Behavior and History Matching
Kheidri, L. H. (TOTAL) | Vanhalst, M.. (TOTAL) | Barroso, F.. (TOTAL) | Fadipe, A.. (TOTAL) | Al Hammadi, Y.. (ADNOC) | Al Junaibi, F.. (ADNOC) | Adli, M.. (ADNOC) | Ben Sadok, A.. (ADMA-OPCO) | Baslaib, M.. (ADMA-OPCO) | Dreno, C.. (TOTAL) | Mel, R.. (TOTAL) | Audigier, P. A. (TOTAL) | Perroud, S.. (TOTAL) | Vacheyrout, A.. (TOTAL)
Abstract The presence of residual oil below Free Water Level is common in Middle Eastern fields. This later is explained by the presence of a paleo oil-water contact. An early water movement and sweep of the accumulated oil induced by tectonic events after its charging, has led to the trapping of residual oil below the curent Free Water Level. This theory is also supported by the presence of tarmat above and below this Free Water Level along the paleo oil-water contact. In the studied field, the analysis of fluid saturation logs, early well tests and initial fluid gradients have led to the definition of the oil-water contact and the Free Water Level at discovery time. The analyses of cored wells and water saturation logs have demonstrated the presence of oil below this Free Water Level which is explained by the presence of a paleo oil-water contact. Furthermore, this analysis has enabled the definition of the geometry of this paleo oil-water contact, which appears to have a curved shape. This geometry has also been confirmed by the presence of tarmat along the defined paleo contact. Modeling of the water and oil saturations below Free Water Level cannot be achieved by a conventional methodology using a saturation height function. Therefore a specific workflow has been developed. Given that oil saturation below Free Water Level is rock type driven, it could be distributed in 3D as any static property. Water saturation logs were consequently upscaled and populated in 3D using a Sequential Gaussian Simulation algorithm with the rock types as main driver. The resulting grid has been extracted up to the base of the transition zone of the main oil column and merged with the oil saturation grid generated using a saturation height function. A thorough dynamic synthesis of the field has highlighted a specific dynamic behavior of the water injectors perforated below the Free Water Level. In some specific intervals of the reservoir, high shut-in pressures have been identified. These high pressures can be explained by the presence of residual oil below the Free Water Level which acts as a baffle inducing a partial confinement of the injectors. The implementation of this residual oil in the simulation model reduces the injected water mobility and drastically improves the pressure match.
- Geology > Geological Subdiscipline (0.69)
- Geology > Rock Type (0.55)
- Geology > Structural Geology > Tectonics (0.35)
- Asia > Middle East > UAE > Abu Dhabi > Arabian Gulf > Rub' al Khali Basin > Diyab Formation (0.99)
- Asia > Middle East > Qatar > Arabian Gulf > Rub' al Khali Basin > Bul Hanine Field (0.99)
- Asia > Middle East > Kuwait > Jahra Governorate > Arabian Basin > Widyan Basin > Minagish Field > Marrat Formation > Upper Marrat Formation > Sargelu Formation (0.99)
- (12 more...)