Equatorial Guinea
Estimation of Water Cut, Gas Oil Ratio and Inflow Parameters for Deep Water Wells with Infrequent Well Tests Using Regression-Based Method
Nandanwar, Manish (ExxonMobil Services & Technology Private Limited, Bengaluru, Karnataka, India) | Lolla, Sri (ExxonMobil Global Projects Company, Spring, Texas, USA) | Pareek, Aditya (ExxonMobil Services & Technology Private Limited, Bengaluru, Karnataka, India) | Pandya, Rohan (ExxonMobil Services & Technology Private Limited, Bengaluru, Karnataka, India) | Gupta, Robin (ExxonMobil Services & Technology Private Limited, Bengaluru, Karnataka, India) | Kedia, Kushal (ExxonMobil Services & Technology Private Limited, Bengaluru, Karnataka, India)
Abstract Real-time production surveillance and optimization requires availability of predictive well models with reasonable accuracy that can estimate production rates in response to change in operating conditions. These models that are mostly physics based are parameterized in terms of gas oil ratio (GOR), water cut (WC), productivity index (PI), and reservoir pressure. Further, the models are tuned using measured data namely production rates of oil, water, gas, and pressure measurements such as downhole gauge pressure, wellhead and flowline pressures that are captured during a well test. For mature oil fields where, well tests are infrequent or sensors start malfunctioning, relevant data required for model tuning is no longer available. In absence of updated models, real-time predictions tend to deviate with time compared to the observed data resulting in less reliable well rate allocation and production optimization recommendations, if any. This work describes a regression-based technique and its application for predicting quantitative as well as directional changes in well parameters between well tests that can be used to improve well allocations. A regression method that estimates well parameters while minimizing a non-linear least square loss function derived from deviation between measured and model-based estimates of rate and pressure data is implemented. The method can estimate well parameters for both an individual and multiple wells simultaneously while solving for a network of wells connected to production separator using IPM GAP. The application of the method to a subsea asset is demonstrated while evaluating its performance for different scenarios comprising variation in number of wells and well parameters. Additionally, the capability of the method to predict directional changes in well parameters is demonstrated by validating it against historical data. The estimates from regression method were found within 5% difference compared to well parameters obtained from multiphase flow meters for the scenarios where number of wells and the number of regression parameters per well were limited. This difference increased with increase in number of wells and number of regression parameters per well owing to the fact that solution space expands with increased degrees of freedom. However, the directional changes in parameters were predicted accurately when looked at larger time scales. It was inferred that the application of regression method is best suited for the scenarios where well parameter estimations are needed for a limited number of wells and the parameters for the remaining wells in a network are representative. Additionally, availability and reliability of sensor data largely impacts the method outcomes.
- Asia > Middle East (0.70)
- North America > United States > Texas (0.69)
- Africa > Equatorial Guinea > Gulf of Guinea > Rio Muni Basin > Okume Complex > Oveng Field > Block G > Oveng Field (0.99)
- Africa > Equatorial Guinea > Gulf of Guinea > Rio Muni Basin > Okume Complex > Oveng Field > Block G > Okume Field (0.99)
- Africa > Equatorial Guinea > Gulf of Guinea > Rio Muni Basin > Okume Complex > Oveng Field > Block G > Okume Complex (0.99)
- (71 more...)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Drillstem/well testing (1.00)
- Production and Well Operations > Well & Reservoir Surveillance and Monitoring > Downhole and wellsite flow metering (1.00)
- Reservoir Description and Dynamics > Formation Evaluation & Management > Well performance, inflow performance (0.93)
First Successful Execution of Miscible Gas Injection EOR Pilot in Kuwait: Challenges and Opportunities
Pradhan, A. (Kuwait Oil Company) | Al-Mayyan, H. (Kuwait Oil Company) | Kamal, D. (Kuwait Oil Company) | Ziyab, K. (Kuwait Oil Company) | Nurafza, P. (Shell Global Solutions International B.V.) | Srivastava, A. (Shell Global Solutions International B.V.) | Mishra, S. (Shell Global Solutions International B.V.) | Faulkner, T. (Shell Global Solutions International B.V.)
Abstract A hydrocarbon gas injection pilot was successfully conducted in a heterogeneous multilayered Oolitic carbonate reservoir in Kuwait. The pilot strived towards de-risking technical and commercial feasibility for field-scale deployment of miscible CO2 WAG EOR development. The aim was to generate reliable unambiguous pilot performance results on remaining oil saturation, inflow profile and sweep efficiency to better quantify risks and uncertainties. This paper describes design, execution, and results of this pilot and its challenges and opportunities. The pilot was an inverted four-spot, consisted of a pre-flush water injection phase (2016-19), drilling and coring two fiberglass cased observation wells, followed by a gas injection phase (2021-2022). The phases were carried-out sequentially in three target layers, injecting a range of pore volumes in each layer. The pre-flush surveillance program included Inter-well water tracer test (IWTT), time-lapse saturation logging, coring, PLT/ILT, VIT, PGOR and ESP monitoring of the pilot wells. The gas injection phase surveillance in addition constituted gas tracers, pressure transient data and time-lapse saturation logging in the two observation wells to monitor the gas flood front movement. The immediate impact of this miscible gas injection pilot was the bolstering oil production increase and water-cut reduction in several pilot wells in relatively short pilot duration, persuading the management to high-grade CO2 full-field development as in-plan firm project. An integrated analysis of all the gathered data was conducted, providing an insight on reservoir de-saturation, inflow and sweep for the pre-flush and gas injection phases along with the achieved oil gain, assisting better understanding of the implications for future CO2 Water Alternating Gas (WAG) Enhanced Oil Recovery (EOR) full field pattern development. Detailed integrated static and dynamic modeling of the pilot area were conducted using compositional simulation models, incorporating pre-flush and gas injection phase data, history matched to production, injection, GOR, water-cut, pressure, tracer production concentration and arrival time, ILT/PLT and time-lapse saturation logs. This detailed assessment revealed the impact of heterogeneity including horizontal baffles and barriers on the displacement process. The water and gas tracer analysis provided a unique opportunity to conduct Residence Time Distribution (RTD) analysis to assess, quantify, and compare heterogenous flow patterns and swept volumes for both water and gas transport between well pairs in different reservoir layers. Novel integrated workflow consisting of robust surveillance techniques, reservoir modelling workflows along with tracer analysis techniques were used in this complex heterogeneous multi-layered carbonate reservoir study in understanding pore scale and reservoir scale sweep efficiency and its impact on oil recovery. The immediate increase in oil production in pilot and surrounding wells has provided KOC the much-needed opportunity in designing a road map for commercial deployment of CO2 WAG in this world class field.
- Energy > Oil & Gas > Upstream (1.00)
- Water & Waste Management > Water Management > Lifecycle > Disposal/Injection (0.35)
- North America > Trinidad and Tobago > Trinidad > North Atlantic Ocean > Columbus Basin (0.99)
- Africa > Equatorial Guinea > Gulf of Guinea > Benita prospect > Block I > I-1 Well (0.99)
- Africa > Equatorial Guinea > Gulf of Guinea > Block O > O-1 Well (0.93)
Wellesley Petroleum struck a gas-condensate column with its exploration well 35/10-10 S at its Carmen prospect using semisubmersible rig Deepsea Yantai in the Norwegian North Sea. The well encountered a 210-m gas-condensate column in the Ness, Etive, and Oseberg formations, 90 m of which is in sandstone layers with poor to good permeability. A 70-m gas-condensate column was also encountered in the Cook formation, 23 m of which is sandstone with poor permeability. A 13-m light-oil column was also found in sandstones in the Early Jurassic Amundsen Formation. No formation water was encountered in the well.
- Europe > Norway > North Sea > Cook Formation (0.99)
- Africa > Equatorial Guinea > Gulf of Guinea > Carmen prospect (0.99)
- Europe > United Kingdom > North Sea > Central North Sea > Ness Formation (0.94)
- (8 more...)
Norwegian oil and gas operator DNO announced a significant gas and condensate discovery on the Carmen prospect in the Norwegian North Sea, License PL1148. Preliminary evaluation of comprehensive data, including cores and fluid samples acquired from the discovery well and a follow-on extended sidetrack, indicates gross recoverable resources in the range of 120 million–230 million BOE. The two wells have established a deeper hydrocarbon/water contact, tripling the midpoint of DNO's predrill expected range. The other partners in the license are Wellesley Petroleum as operator with 50% interest and Equinor and Aker BP with 10% each.
An Integrated Approach for the Geologic Model Construction of a Miocene Turbidite Reservoir in the Akpo Field, Niger Delta.
Author, G. O. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.) | Author, C. C. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.) | Author, E. A. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.) | Author, O. O. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.) | Author, M. O. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.) | Author, V. S. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.) | Author, C. O. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.) | Author, G. U. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.) | Author, M. F. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.) | Author, C. E. (TotalEnergies EP Nigeria Limited, Victoria Island, Lagos State, Nigeria.)
Abstract Geologic model updates especially when driven by seismic data generally help for better field understanding, and in most cases, aid the targeting of nearby undeveloped prospects or infill opportunities and robust geosteering of infill wells for efficient drainage or sweep and well recovery optimization which help to prolong field life and maximize the returns on investment of mature fields. The Akpo V & W reservoirs case study lie in the central part of the mature Akpo field. They are characterized by laterally offset stacked turbidite channels with dense network of faults. This work illustrates the collaborative team effort performed through the integration of geoscience and reservoir engineering data in constructing the static model of the V & W reservoirs. This new model aims to address the uncertainties and limitations of the previous model, re-evaluate the volumes in place, better represent the dynamic behavior of the reservoirs to aid history match, forecast and optimize infill well placements within undrained areas to sustain production. This will in turn, improve the recovery factor and the management of the reservoirs. The new model incorporates new petrophysical synthesis for all development wells, re-interpreted faults, horizons and AEs on a new seismic dataset (2018 4D M3 B98), Lithofacies trends from seismic reservoir characterization study, amongst others. Structural and property modelling results with QCs shows better respect of well, seismic data/trends and facies heterogeneities; giving rise to a more robust model that meets the specified objectives.
- Africa > Nigeria > Niger Delta (0.84)
- Africa > Nigeria > Gulf of Guinea > Niger Delta (0.63)
- Geology > Structural Geology (1.00)
- Geology > Rock Type > Sedimentary Rock > Clastic Rock (0.85)
- Geology > Sedimentary Geology > Depositional Environment > Marine Environment > Deep Water Marine Environment (0.61)
- Africa > Nigeria > Gulf of Guinea > Niger Delta > Niger Delta Basin > OPL 246 > Akpo Field (0.99)
- Africa > Nigeria > Gulf of Guinea > Niger Delta > Niger Delta Basin > OML 130 > Akpo Field (0.99)
- Africa > Cameroon > Akata Formation (0.98)
- (2 more...)
A discovery in the Norwegian North Sea east of the Troll Field surprised its partners by far exceeding their highest expectations. The Carmen discovery announced Monday is expected to deliver from 120–230 million BOE, topping the 20 million–100 million BOE estimate made before the exploration well was drilled in the Troll-Gjøa area, according to DNO, a public company which holds a 30% stake. Wellesley Petroleum, a private company holding 50%, is the operating partner. The estimate tripled the predrill expectation because "the hydrocarbon-water content was deeper than expected." The 175 million BOE midpoint on the recoverable resource estimate would make it the biggest find offshore Norway since 2013, according to the release, which did not name that field.
- South America > Peru > Loreto Department > Marañón Basin > Block 192 > Carmen Field > Vivian Formation (0.99)
- South America > Peru > Loreto Department > Marañón Basin > Block 192 > Carmen Field > Cushabatay Formation (0.99)
- South America > Peru > Loreto Department > Marañón Basin > Block 192 > Carmen Field > Chonta Formation (0.99)
- (18 more...)
To foster free scientific communication camps for geoscience students. The Foundation has expanded among members, SEG has placed a new emphasis on the the Trustee Associates group and has a renewed focus on Forum Series of meetings. We have long held the D&P implementing a major-gifts campaign to significantly increase Forum, and this concept has been expanded to cover all areas the corpus. We are doing well by these traditional measures, of the geosciences. This year, we held two new very successful but of course SEG is much more than this.
- South America (1.00)
- North America > United States > Texas (1.00)
- Europe (1.00)
- (3 more...)
- Research Report (1.00)
- Personal > Honors (1.00)
- Instructional Material > Course Syllabus & Notes (1.00)
- Overview > Innovation (0.67)
- Geology > Geological Subdiscipline > Geomechanics (1.00)
- Geology > Geological Subdiscipline > Economic Geology > Petroleum Geology (0.45)
- Geophysics > Seismic Surveying > Surface Seismic Acquisition (1.00)
- Geophysics > Seismic Surveying > Seismic Processing (1.00)
- Geophysics > Magnetic Surveying (1.00)
- (3 more...)
- Media (1.00)
- Law (1.00)
- Government > Regional Government > North America Government > United States Government (1.00)
- (5 more...)
- South America > Brazil > Rio de Janeiro > South Atlantic Ocean > Campos Basin > Enchova Cluster > Pirauna Field (0.99)
- South America > Brazil > Campos Basin (0.99)
- North America > United States > Texas > Permian Basin > Yeso Formation (0.99)
- (38 more...)
- Information Technology > Artificial Intelligence (0.67)
- Information Technology > Communications > Networks (0.45)
Summary Flow rate is a valuable piece of information for the oil and gas industry. High accuracy on flow rate estimation enhances the operations that control and manage production. Recognized as a cost-efficient solution, the virtual flowmeter (VFM) is a mathematical-based technology designed to estimate the flow rates using available field instrumentation. The VFM approach developed in this work combines black-box simulations with mixed-integer linear programming (MILP) problems to obtain flow rates while dismissing the tuning process. The methodology includes a set of multiphase flow correlations. The MILP estimates the flow rate and designates the best-fit model. The VFM is evaluated against 649 well test data. The methodology presents a 4.1% absolute percentage error (APE) for the 25th percentile and 13.5% APE for the 50th percentile of the data. The methodology dismisses the model tuning process, which would require flow rate data. This makes the methodology valuable, particularly in scenarios where historical data are scarce or unavailable.
- Europe (1.00)
- South America (0.68)
- North America > United States > Texas (0.46)
- (2 more...)
- North America > Trinidad and Tobago > Trinidad > North Atlantic Ocean > Venzuela Basin > Darien Ridge > Block 2c > Greater Angostura Field > Angostura Field (0.99)
- Asia > Kazakhstan > Atyrau Oblast > Caspian Sea > Precaspian Basin > Kashagan Field (0.99)
- Africa > Equatorial Guinea > Gulf of Guinea > Rio Muni Basin > Okume Complex > Okume Complex > Ceiba Field > Block S > Okume Complex > Ceiba Field > Barremian-Aptian Dentale Formation (0.99)
- Africa > Equatorial Guinea > Gulf of Guinea > Rio Muni Basin > Okume Complex > Okume Complex > Ceiba Field > Block G > Okume Complex > Ceiba Field > Barremian-Aptian Dentale Formation (0.99)
- Reservoir Description and Dynamics (1.00)
- Production and Well Operations > Well & Reservoir Surveillance and Monitoring > Production logging (1.00)
- Production and Well Operations > Well & Reservoir Surveillance and Monitoring > Downhole and wellsite flow metering (1.00)
- Data Science & Engineering Analytics > Information Management and Systems > Artificial intelligence (1.00)
- Information Technology > Sensing and Signal Processing (1.00)
- Information Technology > Artificial Intelligence > Machine Learning (1.00)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Mathematical & Statistical Methods (0.54)
- Information Technology > Artificial Intelligence > Representation & Reasoning > Optimization (0.48)
Subsea Processing Systems: An Overview of Promising Technologies on the Subsea Factory Decarbonization Path
Basilio, Leandro Pereira (Deep Seed Solutions) | Machado, Priscilla Badega (Deep Seed Solutions) | Sousa, Luara Katarine Silva (Deep Seed Solutions) | de Sousa, Débora Calaza (Deep Seed Solutions) | de Castro, Rafael Vinicius (Deep Seed Solutions) | dos Anjos, Rodrigo Petrone (Deep Seed Solutions) | Andreotti, Marcelo (Repsol Sinopec Brasil) | Juliano, Diego Russo (Shell Brasil Petróleo Ltda.) | Chaney, Carmela (ExxonMobil) | Matos, Sarah (ExxonMobil) | Ryu, Sam (ExxonMobil)
Abstract The proper development of an offshore oil and gas field relies on a project's ability to deliver the maximum economic benefits while maintaining safety and environmental targets. In this sense, offshore oil and gas companies have continually evaluated ways to optimize system designs and streamline operations to ensure the achievement of these objectives. A set of technological alternatives that have been highlighted is subsea processing, which requires moving a processing system from the topsides to the seabed. The assessment of subsea processing systems has become an important step during the field development strategy definition, especially in terms of flow assurance by mitigating hydrate and wax formation. When combined with mature subsea production technologies, the potential benefits of deploying subsea processing include enhanced reservoir recovery improved facilities availability, reduced topsides processing requirements, and reduced overall field development cost resulting in improvement of project economics. In addition, depending on the subsea architecture chosen, subsea processing can contribute to reducing the carbon footprint, which is in line with the industry's decarbonization goals. Due to the potential benefits of the subsea processing architectures, new technologies are emerging to overcome the technical challenges to enable this transfer of strategic processes from the topsides to the subsea. The objective of this paper is to present and discuss the mapped subsea processing system archetypes that may significantly increase hydrocarbon production in a cost-optimized way for new fields, tiebacks, and operating facilities. The mapped archetypes are implemented in an Expert System that integrates all technical areas for offshore field development, providing hundreds of conceptual alternatives to understand the impact of using subsea processing systems. This paper provides an overview of promising technologies that have the potential to increase the scope of subsea processing, leading to the identification of the most favorable architectures for each project. This study incorporates a detailed analysis of 27 different subsea archetypes, combining processes such as liquid boosting to host, gas compression to host, two-phase and three-phase separation, produced water reinjection or disposal, seawater injection with sulphate removal, dense phase (natural gas or CO2) boosting to reinjection, gas dehydration, and gas compression. Such analysis indicated that equipment with different technological maturity levels can be combined to create a subsea processing arrangement that meets the project requirements.
- North America > United States > Texas > Coleman County (0.24)
- North America > United States > Texas > Harris County > Houston (0.16)
Use of multibeam bathymetry and backscatter to improve seabed geochemical surveys — Part 2: Best practices and case studies in seep hunting for exploration, with an emphasis on Indonesia
Orange, Daniel L. (Oro Negro Exploration LLC (ONE)) | Teas, Philip A. (Oro Negro Exploration LLC (ONE)) | Decker, John (Oro Negro Exploration LLC (ONE)) | Gharib, Jamshid (Fugro USA Marine, Inc.)
Abstract The successful sampling of seafloor oil and gas seeps can provide information on source rock, migration, maturation, and charge that can impact exploration decisions. Although 3D seismic data can be interpreted for potential seafloor seeps, multibeam can be acquired over larger areas at lower cost and in a shorter turnaround time, with bathymetry, backscatter, and water column imagery leading to the interpretation of potential seafloor seep targets. The use of multibeam-based exploration early in an exploration project can provide information on the petroleum systems in an area and also areas where no evidence of a petroleum system is present on the seafloor. We have developed case studies of block-specific seep hunting and regional multibeam surveys. For regional surveys, multibeam can be combined with 2D seismic data, ultrashort baseline (USBL)-positioned piston coring, heat flow, high-resolution subbottom profiles, marine gravity and magnetics, and core geochemistry to evaluate exploration potential. The first multibeam-for-exploration survey, with cores acquired for geochemistry, was carried out in 2000 offshore Barbados. Applying a tool used in academia and other industry projects, USBL positioning in real-time in a Geographical Information System (GIS) environment was used to confidently place a core barrel on a seafloor seep target beginning in 2002. In 2003, Unocal acquired the first basin-wide multibeam survey for exploration and demonstrated that multibeam can rapidly interrogate a very large area at a relatively modest cost. Indonesia basin- and regional-scale projects demonstrated the value of multibeam-based exploration through the successful farm-out of exploration blocks with a promotion (in which the farm-in-ee(s) pays a higher percentage of costs than their percentage of equity). We review several examples of seep studies, with an emphasis on Indonesia; target selection philosophy, criteria, and ranking; and target types. Mud volcano and hard substrate sampling can provide information on the subsurface without drilling.
- Asia > Indonesia (1.00)
- North America > United States > Texas (0.67)
- North America > United States > California (0.67)
- North America > United States > Gulf of Mexico > Central GOM (0.27)
- Overview (0.66)
- Research Report (0.48)
- Phanerozoic > Mesozoic > Jurassic (0.67)
- Phanerozoic > Cenozoic > Neogene (0.46)
- Phanerozoic > Cenozoic > Paleogene (0.46)
- Geology > Geological Subdiscipline > Geochemistry (1.00)
- Geology > Geological Subdiscipline > Economic Geology > Petroleum Geology (1.00)
- Geology > Structural Geology > Tectonics > Compressional Tectonics > Fold and Thrust Belt (0.46)
- Oceania > Australia > Western Australia > North West Shelf > Browse Basin > Block WA-315-P > Plover Formation (0.99)
- Oceania > Australia > Western Australia > North West Shelf > Browse Basin > Block WA-274-P > Plover Formation (0.99)
- North America > United States > Texas > Permian Basin > Brooks Field > Canyon K Formation (0.99)
- (20 more...)