The Integrated Technology of Residual Reserves Localization and Profit Increase on Brownfields

Abstract Brown fields that are currently experiencing production decline can benefit a lot from production enhancement operations based on localization of residual reserves and geology clarification. The set of solutions includes targeted recommendations for additional well surveys followed by producers and injectors workovers, like whole wellbore or selective stimulation, polymer flow conformance, hydraulic fracturing and side tracking. As a result, previously poorly drained areas are involved in production, which increases current rates and ultimate recovery. The integrated technology of residual reserves localization and production increase includes: Primary analysis of the production history for reservoir blocks ranking by production increase potential. Advanced bottom-hole pressures and production history analysis by multiwell deconvolution for pressure maintenance system optimization and production enhancement. Advanced production logging for flow profile and production layer-by-layer allocation. Conducting pulse-code interference testing for average saturation between wells estimation. 3D reservoir dynamic model calibration on advanced tests findings. Multi-scenario development planning for the scenario with biggest NPV regarding surface infrastructure. The presented integrated technology is carried stage by stage. Based on the data analysis at the first stage (the Prime analysis) it is possible to get three types of results. The top-level assessment of the current development opportunities of the area, evaluation of current residual reserves on base of displacement sweep efficiency estimation, and evaluation of the potential production increase for various blocks of the field. Results of the second stage were obtained for the block deemed with the highest potential for production increase. Those results may reveal possible complications, and relevant workovers can be advised along with additional surveys that can further help to locate current reserves. The last stage of Prime analysis provides the most suitable choice was to perform an advanced logging and well-testing, as they include both single-well and multi-well tests. Pulse-code interference tests, multi-well retrospective tests and reservoir-oriented production logging make it possible to scan the reservoir laterally and vertically, which is especially important for multi-layered fields. The reservoir parameters obtained from the test results are used to calibrate the dynamic reservoir model. The effects of production enhancement operations are calculated from the 3D model. The set of possible activities is evaluated in terms of their financial efficiency based on the economic model of the operator company using multi-scenario approach on a specifically created digital twin of the field. The unique feature of this approach lies in an integrated usage of advanced production history analysis, advanced logging and well-testing technologies, as well as further calibration of the dynamic reservoir model based on test results and used-friendly interface for field digital twin interaction. This paper demonstrates on how to use the field tests results to calibrate the reservoir model and increase the accuracy of production forecasting by reducing the model uncertainty, with intent to increase profit of brownfields.

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Well Testing: Effect of Scaleup and Aggregation on the Analysis of Interference Tests

Journal of Petroleum Technology ◽

10.2118/0204-0059-jpt ◽

2004 ◽

Vol 56 (02) ◽

pp. 59-60

Author(s):

Dennis Denney

Keyword(s):

Testing Effect ◽

Well Testing ◽

Interference Tests

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Development of Deep Transformer-Based Models for Long-Term Prediction of Transient Production of Oil Wells

10.2118/206537-ms ◽

2021 ◽

Author(s):

Ildar Radikovich Abdrakhmanov ◽

Evgenii Alekseevich Kanin ◽

Sergei Andreevich Boronin ◽

Evgeny Vladimirovich Burnaev ◽

Andrei Aleksandrovich Osiptsov

Keyword(s):

Neural Networks ◽

Transfer Learning ◽

Multivariate Time Series ◽

Operating Regime ◽

Oil Wells ◽

Well Testing ◽

Novel Approach ◽

Production History ◽

Single Well ◽

Bottomhole Pressure

Abstract We propose a novel approach to data-driven modeling of a transient production of oil wells. We apply the transformer-based neural networks trained on the multivariate time series composed of various parameters of oil wells measured during their exploitation. By tuning the machine learning models for a single well (ignoring the effect of neighboring wells) on the open-source field datasets, we demonstrate that transformer outperforms recurrent neural networks with LSTM/GRU cells in the forecasting of the bottomhole pressure dynamics. We apply the transfer learning procedure to the transformer-based surrogate model, which includes the initial training on the dataset from a certain well and additional tuning of the model's weights on the dataset from a target well. Transfer learning approach helps to improve the prediction capability of the model. Next, we generalize the single-well model based on the transformer architecture for multiple wells to simulate complex transient oilfield-level patterns. In other words, we create the global model which deals with the dataset, comprised of the production history from multiple wells, and allows for capturing the well interference resulting in more accurate prediction of the bottomhole pressure or flow rate evolutions for each well under consideration. The developed instruments for a single-well and oilfield-scale modelling can be used to optimize the production process by selecting the operating regime and submersible equipment to increase the hydrocarbon recovery. In addition, the models can be helpful to perform well-testing avoiding costly shut-in operations.

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INTEGRATED TECHNOLOGY OF BROWN FIELD STUDY TO INCREASE PRODUCTION AND OIL RECOVERY

Энергия экономика техника экология ◽

10.7868/s2587739920020081 ◽

2020 ◽

pp. 61-66

Author(s):

I.A. Zhdanov ◽

E.S. Pakhomov ◽

A.M. Aslanyan ◽

R.R. Farakhova ◽

D.N. Gulyaev ◽

...

Keyword(s):

Oil Recovery ◽

Field Studies ◽

Development Planning ◽

Reservoir Modeling ◽

Integrated Analysis ◽

Well Testing ◽

Reservoir Model ◽

Scenario Development ◽

Sweep Efficiency ◽

High Level

Paper presents the results of integrated analysis of historically available data and additional field studies at the brown field. The results of the analysis increase the reliability of the geological and hydrodynamic reservoir model, current recovery and identification of areas, which are most promising for production enhancement operations for production increase and recovery increase. The integrated analysis of available data includes such tools as prelaminar data analysis of production and pressure changes (Prime) for high level reserves localization, multiwell retrospective testing (MRT) and pulsecode testing (PCT) for evaluation of reservoir geology, sweep efficiency and current reservoir saturation, geological and hydrodynamic reservoir modeling including petrofacies and model adaptation to the production logging, MRT, PCT and well-testing findings, multi-scenario development planning (MSDP) for the most economically profitable operations recommendation and supervision of their implementation. MSDP is based on the usage by several teams of reservoir engineers web-facility PloyPlan, which automatically translates the field activities (like drilling, workover, conversion, surveillance, etc.) into the model runs and reverts back with production and surveillance results and financial statements, based on which it is easy to choose the most profitable field operations. Up to today Prime analysis, field studies and reservoir model calibration on their results are finished.

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Research on Methods for Elastic Stiffness of Multi-Ribbed Slab Structure

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.1736 ◽

2010 ◽

Vol 97-101 ◽

pp. 1736-1740

Author(s):

Qi Zhang ◽

Dong Bo Li ◽

Qian Feng Yao ◽

Dong Zhao

Keyword(s):

Time History ◽

Elastic Stiffness ◽

Structural Effect ◽

Time History Analysis ◽

Equivalent Model ◽

Test Results ◽

History Analysis ◽

Set Up

Considering the influence of the flange and rib column, the equivalent model of multi-ribbed slab is set up by the theory based on the strengthening isotropism fiber. This model is simple, highly precise and strongly applicable through comparing analyzing results with test results. Besides, the calculated formulate is set up on the basis of the whole structural effect and space work, which offers the prerequisite for elastic time history analysis of the structure.

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CSG well testing—Santos' experience in Queensland

The APPEA Journal ◽

10.1071/aj12020 ◽

2013 ◽

Vol 53 (1) ◽

pp. 227

Author(s):

Czek Hoong Tan ◽

Guncel Demircan ◽

Mathias Satyagraha

Keyword(s):

Radial Flow ◽

Test Methods ◽

Well Testing ◽

Test Results ◽

Well Test ◽

Well Performance ◽

Validity Of Results ◽

Transient Behaviour ◽

Key Factor ◽

Primary Porosity

Permeability of the cleat system is a key factor controlling the productivity of CSG reservoirs and, therefore, the commerciality of development projects. Well testing is routinely used to provide representative values of coal permeability. The authors’ experience has shown pressure transient behaviour in coal reservoirs to be similar to those in primary porosity systems, with pseudo radial flow frequently observed, and the dual-porosity signature largely absent. Despite the authors’ best efforts in test design, large permeability variation and extremely high skin factors have been seen. The authors have run variations of drill stem tests (DSTs), injection tests, and wireline tests to understand the dependency of results to test methods, and the validity of results obtained. Pertinent examples of each type of test are discussed. Finally, recommendations to reconcile well test results to actual well performance are presented.

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Inferring Interwell Connectivity from Well Bottomhole-Pressure Fluctuations in Waterfloods

SPE Reservoir Evaluation & Engineering ◽

10.2118/106881-pa ◽

2008 ◽

Vol 11 (05) ◽

pp. 874-881 ◽

Cited By ~ 9

Author(s):

Djebbar Tiab ◽

Anh V. Dinh

Keyword(s):

Pressure Fluctuations ◽

The Other ◽

Time Interval ◽

Well Testing ◽

Production Rates ◽

Data Points ◽

Interwell Connectivity ◽

Reservoir Simulator ◽

Interference Tests ◽

Bottomhole Pressure

Summary This paper presents a new procedure to determine interwell connectivity in a reservoir on the basis of fluctuations of bottomhole pressure of both injectors and producers in a waterflood. The method uses a constrained multivariate linear-regression (MLR) analysis to obtain information about permeability trends, channels, and barriers. Previous authors applied the same analysis to injection and production rates to infer connectivity between wells. In order to obtain good results, however, they applied various diffusivity filters to the flow-rate data to account for the time lags and the attenuation. This was a tedious process that requires subjective judgment. Shut-in periods in the data, usually unavoidable when a large number of data points were used, created significant errors in the results and were often eliminated from the analysis. This new method yielded better results compared with the results obtained when production data were used. Its advantages include:no diffusivity filters needed for the analysis,minimal number of data points required to obtain good results,and flexible plan to collect data because all constraints can be controlled at the surface. The new procedure was tested by use of a numerical reservoir simulator. Thus, different cases were run on two fields, one with five injectors and four producers and the other with 25 injectors and 16 producers. For a large waterflood system, multiple wells are present and most of them are active at the same time. In this case, pulse tests or interference tests between two wells are difficult to conduct because the signal can be distorted by other active wells in the reservoir. In the proposed method, interwell connectivity can be obtained quantitatively from multiwell pressure fluctuations without running interference tests. Introduction Well testing is a common and important tool of reservoir characterization. Many well-testing methods have been developed in order to obtain various reservoir properties. Interference tests and pulse tests are used to quantify communication between wells. These methods are often applied to two wells such that one well sending the signals (by changing flow rates) and the other is receiving them (Lee et al. 2003). For a large field such as a waterflood system, however, multiple wells are present, and most of them are active at the same time. In that case, pulse tests or interference tests between two wells are difficult to conduct because the signal can be distorted by other active wells in the reservoir. In this method, data can be obtained from multiwell pressure tests that resemble interference tests. Thus, we can have several wells sending signals and the others receiving the signals at the same time. The wells that are receiving the signal, however, can either be shut in or kept at constant producing rates. The pressures at all wells are recorded simultaneously within a constant time interval. The length of the test will depend on the length of the time interval and the number of data points. Results of this method can be used to optimize operations and economics and enhance oil recovery of existing waterfloods by changing well patterns, changing injection rates, recompletion of wells, and infill drilling. This work is based on previous work conducted by Albertoni and Lake (2003) by use of injection and production rates. In their work, Albertoni and Lake developed and tested different approaches by use of constrained MLR analysis with a numerical simulator and then applied it to a waterflooded field in Argentina. They used diffusivity filters to account for the time lag and attenuation of the data. In his thesis, Dinh (2003) verified the method by use of a different reservoir simulator and applied it to a waterflooded field in Nowata, Oklahoma. He also investigated the effect of shut-in periods and vertical distances on the results. The main objectives of this work are to verify the results obtained from pressure data with results from flow-rate data to propose a new method to determine interwell connectivity and to suggest further research and study on the method. Similar to the method that uses production rates, we will concentrate on a waterflood system only. The reservoir is considered as a system that processes a stimulus (i.e., a well that is sending signals) and returns a response (i.e., a well that is receiving the signals). The effect of the reservoir on the input signal will depend on the location and the orientation of each stimulus/response pair. Because the total pressure changes at active and observation wells are not equal, only the MLR (Albertoni and Lake 2003; Dinh 2003; Albertoni 2002) was used. The effect of diffusion was not significant, thus the diffusivity filters were not used. The method was applied to two synthetic fields, one with five injectors and four producers and the other with 25 injectors and 16 producers.

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Transient Nonisothermal Fully Coupled Wellbore/Reservoir Model for Gas-Well Testing, Part 1: Modelling

Journal of Canadian Petroleum Technology ◽

10.2118/149617-pa ◽

2011 ◽

Vol 50 (9/10) ◽

pp. 37-50 ◽

Cited By ~ 14

Author(s):

Mehdi Bahonar ◽

Jalel Azaiez ◽

Zhangxing John Chen

Keyword(s):

Well Testing ◽

Reservoir Model ◽

Gas Well ◽

Fully Coupled

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Gladys McCall Geopressured Reservoir Analysis—June 1987

Journal of Energy Resources Technology ◽

10.1115/1.3231391 ◽

1988 ◽

Vol 110 (4) ◽

pp. 262-268 ◽

Cited By ~ 4

Author(s):

T. D. Riney

Keyword(s):

Conceptual Model ◽

Reservoir Simulation ◽

Cross Flow ◽

Reservoir Model ◽

Short Term ◽

Long Distance ◽

Production History ◽

History Of ◽

Lateral Extent ◽

Reservoir Simulation Model

The Gladys McCall geopressured reservoir consists of an interbedded sequence of relatively thick sands and thin shales. The lateral extent of the reservoir is not well defined. Gladys McCall Well No. 1 produced approximately 4.0×106 m3 (25×106 barrels) of brine from Sand Zone No. 8 from October 7, 1983 through May 1987. Analysis of the flow data from the well has led to the development of a conceptual model of the reservoir, which depends on cross-flow from sands overlying/underlying Sand Zone No. 8 for the observed pressure maintenance. The fluid source is remote from the well in the sense that the fluid from the neighboring sands must flow a long distance to find a vertical pathway around the intervening shale stringers in order to recharge Sand Zone No. 8. A reservoir simulation model based on the conceptual model provides an excellent match to the detailed downhole pressure buildup measurements made during the original Reservoir Limits Test and two subsequent short-term buildup tests. The model has also been employed to match the production history of the Gladys McCall No. 1 well and to predict future reservoir response. Nevertheless, the reservoir model employed is not unique and alternate models for pressure maintenance are also being investigated.

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