Download or read book Production Forecasting in Shale Volatile Oil Reservoirs written by Ibukun Makinde and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis gives us a better understanding of the behavior of shale volatile oil reservoirs. The effects of fluid compositions as well as the sensitivity of certain variables on cumulative oil production and rates were analyzed using black-oil and compositional simulations. Two-phase (oil and gas) black-oil simulations gave better results than single-phase (oil) black-oil simulations. Compositional simulations were much better in comparison to two-phase black-oil simulations. Therefore, for thorough analysis of fluid composition effects and more accurate production forecasts (especially for reservoir fluids like volatile oils in shale formations), compositional simulations are necessary. In this research, single-phase and two-phase black-oil simulations were run on a base case model and the results were compared. Sensitivity studies were carried out by varying certain parameters in the base case model, then single-phase and two-phase black-oil simulations were run and the results were compared to the base case model. This was followed by analyzing six different fluid samples through compositional simulations. Flash calculations were later done on the fluid samples to obtain inputs for two-phase black-oil simulations. Finally, the simulation results from the compositional and two-phase black-oil simulations were then compared. The importance of shale oil and gas research cannot be over-emphasized, given the ever-rising global demand for energy. Research and studies like this, can lead to better well completions and design, improve reservoir management and economics as well as provide insight into potential alternative methods to enhance recovery from unconventional shale formations.

Download or read book Production Forecasting for Shale Oil written by Mazaruny Rincones and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: With the demand for oil rising, unconventional oil reservoirs have taken a prominent role in the United States as a source of crude oil. Different methodologies to estimate reserves for shale gas and coal bed methane have, thus far, proved to be reliable, but no simple yet accurate workflow has been generally accepted to forecast production and estimate reserves for shale oil. To fill this gap in technology, we proposed and validated a workflow that integrates analytical methods with empirical methods. The final methodology is both easily applied and accurate. In developing the final workflow, we evaluated several alternatives, most of which proved to be unsuitable. We also investigated the use of a filter to eliminate outliers in a systematic way, as proposed by Rastogi (2014). The workflow was successfully applied to three of four volatile oil wells in the Eagle Ford shale, with similar results. The analytical model that best matched the wells is called the Stimulated Reservoir Volume (SRV) Bounded Model by the software marketer Kappa. We tested this and other models using a Beta test version of new Kappa software. While accurate, this modeling approach is too time consuming for routine use. We found that a simple empirical approach that led to the same results as the analytical model was a 3-segment Arps decline model. The early flow regime was transient linear for all the wells; thus an Arps --b‖ parameter of two was appropriate. When boundary-influenced flow (BIF) appeared later, b-values of 0.2 were found appropriate. The initial decline rate (Di) value during BIF was modified in mid-segment leading to a distinct third segment. Our workflow also led to reliable forecasts of production (to date) of the gas-oil ratio for the three wells.

Download or read book Improved Reservoir Models and Production Forecasting Techniques for Multi Stage Fractured Hydrocarbon Wells written by Ruud Weijermars and published by MDPI. This book was released on 2019-12-12 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: The massive increase in energy demand and the related rapid development of unconventional reservoirs has opened up exciting new energy supply opportunities along with new, seemingly intractable engineering and research challenges. The energy industry has primarily depended on a heuristic approach—rather than a systematic approach—to optimize and tackle the various challenges when developing new and improving the performance of existing unconventional reservoirs. Industry needs accurate estimations of well production performance and of the cumulative estimated ultimate reserves, accounting for uncertainty. This Special Issue presents 10 original and high-quality research articles related to the modeling of unconventional reservoirs, which showcase advanced methods for fractured reservoir simulation, and improved production forecasting techniques.

Download or read book Production Analysis and Forecasting of Shale Reservoirs Using Simple Mechanistic and Statistical Modeling written by Leopoldo Matias Ruiz Maraggi and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Accurate production analysis and forecasting of well’s performance is essential to estimate reserves and to develop strategies to optimize hydrocarbon recovery. In the case of shale resources, this task is particularly challenging for the following reasons. First, these reservoirs show long periods of transient linear flow in which the reservoir volume grows continuously over time acting without bounds. Second, variable operating conditions cause scatter and abrupt production changes. Finally, the presence of competing flow mechanisms, heterogeneities, and multi-phase flow effects make the production analysis more complex. Detailed numerical flow models can address the complexities present in unconventional reservoirs. However, these models suffer from the following limitations: (a) the uncertainty of many input parameters, (b) susceptibility to overfit the data, (c) lack of interpretability of their results, and (d) high computational expense. This dissertation provides new and simple mechanistic and statistical modeling tools suitable to improve the production analysis and forecasts of shale reservoirs. This work presents solutions to the following research problems. This study develops and applies a new two-phase (oil and gas) flow suitable to history-match and forecast production of tight-oil and gas-condensate reservoirs producing below bubble- and dew-point conditions, respectively. It solves flow equations in dimensionless form and uses only two scaling parameters (hydrocarbon in-place and characteristic time) to history-match production. For this reason, the model requires minimal time to run making it ideal for decline curve analysis on large numbers of wells. This research illustrates the development and application of a Bayesian framework that generates probabilistic production history matches and forecasts to address the uncertainty of model’s estimates. This work uses an adaptative Metropolis-Hastings Markov chain Monte Carlo (MCMC) algorithm to guarantee a fast convergence of the Markov chains by accounting for the correlation among model’s parameters. In addition, this study calibrates the model’s probabilistic estimates using hindcasting and evaluates the inferences robustness using posterior predictive checks. This dissertation examines the problem of evaluation, ranking and selection, and averaging of models for improved probabilistic production history-matching and forecasting. We illustrate the assessment of the predictive accuracy of four rate-time models using the expected log predictive density (elpd) accuracy metric along with cross-validation techniques (leave-one-out and leave-future-out). The elpd metric provides a measure of out-of-sample predictive accuracy of a model’s posterior distribution. The application of Pareto smoothed importance sampling (PSIS) allows to use cross-validation techniques without the need of refitting Bayesian models. Using the Bayesian Bootstrap, this work generates a model ensemble that weighs each individual model based on the accuracy of its predictions. Finally, this research applies a novel deconvolution technique to incorporate changing operating conditions into rate-time analysis of tight-oil and shale gas reservoirs. Furthermore, this work quantifies the errors and discusses the limitations of the standard rate-transient analysis technique used in production analysis of unconventional reservoirs: rate normalization and material balance time

Download or read book A New Method for History Matching and Forecasting Shale Gas oil Reservoir Production Performance with Dual and Triple Porosity Models written by Orkhan Samandarli and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Different methods have been proposed for history matching production of shale gas/oil wells which are drilled horizontally and usually hydraulically fractured with multiple stages. These methods are simulation, analytical models, and empirical equations. It has been well known that among the methods listed above, analytical models are more favorable in application to field data for two reasons. First, analytical solutions are faster than simulation, and second, they are more rigorous than empirical equations. Production behavior of horizontally drilled shale gas/oil wells has never been completely matched with the models which are described in this thesis. For shale gas wells, correction due to adsorption is explained with derived equations. The algorithm which is used for history matching and forecasting is explained in detail with a computer program as an implementation of it that is written in Excel's VBA. As an objective of this research, robust method is presented with a computer program which is applied to field data. The method presented in this thesis is applied to analyze the production performance of gas wells from Barnett, Woodford, and Fayetteville shales. It is shown that the method works well to understand reservoir description and predict future performance of shale gas wells. Moreover, synthetic shale oil well also was used to validate application of the method to oil wells. Given the huge unconventional resource potential and increasing energy demand in the world, the method described in this thesis will be the "game changing" technology to understand the reservoir properties and make future predictions in short period of time.

Download or read book Development of New Decline Model for Shale Oil Reserves written by Samit Shah and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis provides a new methodology to forecast ultimate recovery, based on more reliable production forecast for shale oil wells using historical production data. Compared to available decline curve methods including Arps (AIME: 160, 228-247), Valko (SPE 134231) and Duong (SPE 137748), this method is more accurate and more conservative. Production forecasts play a vital role in determining the value of oil or gas wells, and improved accuracy enhances management decisions on field development. The new, more accurate method was verified using both field data and numerical simulations. This method can potentially be used in most shale reservoirs producing single-phase liquid.

Download or read book History matching and Forecasting of Three Unconventional Oil and Gas Reservoirs Using Decline Analyses and Type Curves written by Hammad Ahmed and published by . This book was released on 2019 with total page 48 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reservoir modeling of shale gas and tight oil presents numerous challenges due to complicated transport mechanisms and the existence of fracture networks. Even then, oil and gas companies have not slowed down on shale hydrocarbon investment and production using horizontal well drilling and hydraulic fracturing techniques. Many small oil companies may not have the budget to build a reservoir model which typically requires drilling test wells and performing well logging measurements. Even for large oil companies, building a reservoir model is not worthwhile for the evaluation of small-scale oil fields. Comprehensive numerical simulation methods are likely impractical in those cases. Decline Curve Analysis (DCA) is one of the most convenient and practical techniques in order to forecast the production of these reservoirs. With the rapid increase in shale hydrocarbon production over the past 30 years, there have been numerous production data for shale gas reservoirs. Many different DCA models have been constructed to model the shale hydrocarbon production rate, from the classical Arps to the latest and more advanced models; each has its advantages and shortcomings. In practice and in all existing commercial DCA software, most of these DCA models are implemented and open to be used. Most of the deterministic DCA models are empirical and lack a physical background so that they cannot be used for history-matching of the reservoir properties. In this study, popular DCA models for shale gas reservoirs are reviewed, including the types of reservoirs they fit. Their advantages and disadvantages have also been presented. This work will serve as a guideline for petroleum engineers to determine which DCA models should be applied to different shale hydrocarbon fields and production periods. The research objective also includes evaluating the performance of top unconventional plays (Bakken, Barnett, and Eagle Ford). Productions by counties are analyzed and compared to see how they stack up against each other. One section of this study also sheds some light on the future of shale gas and tight oil plays based on the simulation of models created.

Download or read book Shale Gas and Tight Oil Reservoir Simulation written by Wei Yu and published by Gulf Professional Publishing. This book was released on 2018-08-10 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shale Gas and Tight Oil Reservoir Simulation delivers the latest research and applications used to better manage and interpret simulating production from shale gas and tight oil reservoirs. Starting with basic fundamentals, the book then includes real field data that will not only generate reliable reserve estimation, but also predict the effective range of reservoir and fracture properties through multiple history matching solutions. Also included are new insights into the numerical modelling of CO2 injection for enhanced oil recovery in tight oil reservoirs. This information is critical for a better understanding of the impacts of key reservoir properties and complex fractures. Models the well performance of shale gas and tight oil reservoirs with complex fracture geometries Teaches how to perform sensitivity studies, history matching, production forecasts, and economic optimization for shale-gas and tight-oil reservoirs Helps readers investigate data mining techniques, including the introduction of nonparametric smoothing models

Download or read book Shale Oil and Gas Production Processes written by James G. Speight and published by Gulf Professional Publishing. This book was released on 2019-11-18 with total page 1048 pages. Available in PDF, EPUB and Kindle. Book excerpt: Shale Oil and Gas Production Processes delivers the basics on current production technologies and the processing and refining of shale oil. Starting with the potential of formations and then proceeding to production and completion, this foundational resource also dives into the chemical and physical nature of the precursor of oil shale, kerogen, to help users understand and optimize its properties in shale. Rounding out with reporting, in situ retorting, refining and environmental aspects, this book gives engineers and managers a strong starting point on how to manage the challenges and processes necessary for the further development of these complex resources. Helps readers grasp current research on production from shale formations, including properties and composition Fill in the gaps between research and practical application, including discussions of existing literature Includes a glossary to help readers fully understand key concepts

Download or read book Recent Developments Affecting Reserve Estimates and Production Forecasting written by and published by . This book was released on 1996 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evaluation of the Stretched Exponential Production Decline Model and Comparison to Other Decline Models for Shale Reservoirs written by Dong Li and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The discovery and development of shale oil/gas has changed the energy industry. By 2040, shale gas production will account for 50% of the total natural gas production of the U.S. Due to the extremely low permeability of shale reservoirs, shale gas wells exhibit much longer transient flow periods than conventional wells, and this makes it inappropriate to use conventional methods of evaluating estimated ultimate recovery (EUR) of wells in these reservoirs. Therefore, new methods of forecasting shale wells are needed. In this study, I focused on the stretched exponential production decline model (SEPD), and particularly Yu’s modification of the model (YM-SEPD). I compared the results with other methods, including Duong’s method, and the Arps hyperbolic model. SEPD provided the most reliable EURs for shale gas well when excluding early off-trend data. YM-SEPD gave results comparable to SEPD and is much easier to apply. It is therefore the method we recommend for shale wells.

Download or read book Application of the Stretched Exponential Production Decline Model to Forecast Production in Shale Gas Reservoirs written by James Cody Statton and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Production forecasting in shale (ultra-low permeability) gas reservoirs is of great interest due to the advent of multi-stage fracturing and horizontal drilling. The well renowned production forecasting model, Arps' Hyperbolic Decline Model, is widely used in industry to forecast shale gas wells. Left unconstrained, the model often overestimates reserves by a great deal. A minimum decline rate is imposed to prevent overestimation of reserves but with less than ten years of production history available to analyze, an accurate minimum decline rate is currently unknown; an educated guess of 5% minimum decline is often imposed. Other decline curve models have been proposed with the theoretical advantage of being able to match linear flow followed by a transition to boundary dominated flow. This thesis investigates the applicability of the Stretched Exponential Production Decline Model (SEPD) and compares it to the industry standard, Arps' with a minimum decline rate. When possible, we investigate an SEPD type curve. Simulated data is analyzed to show advantages of the SEPD model and provide a comparison to Arps' model with an imposed minimum decline rate of 5% where the full production history is known. Long-term production behavior is provided by an analytical solution for a homogenous reservoir with homogenous hydraulic fractures. Various simulations from short-term linear flow (~1 year) to long-term linear flow (~20 years) show the ability of the models to handle onset of boundary dominated flow at various times during production history. SEPD provides more accurate reserves estimates when linear flow ends at 5 years or earlier. Both models provide sufficient reserves estimates for longer-term linear flow scenarios. Barnett Shale production data demonstrates the ability of the models to forecast field data. Denton and Tarrant County wells are analyzed as groups and individually. SEPD type curves generated with 2004 well groups provide forecasts for wells drilled in subsequent years. This study suggests a type curve is most useful when 24 months or less is available to forecast. The SEPD model generally provides more conservative forecasts and EUR estimates than Arps' model with a minimum decline rate of 5%.

Download or read book Probabilistic Oil and Gas Production Forecasting Using Machine Learning written by Robert Andrais and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis improves oil- and gas-well profitability by quantifying the uncertainty of the production-forecasting process, using probabilistic machine learning (ML) techniques. A Bayesian Neural Network successfully modelled a complex shale gas reservoir system (Eagle Ford), generating a production forecast with 5% mean absolute percent error. This result is 10%-35% more accurate than traditional decline curve analysis. These forecasts also quantified the epistemic and aleatory uncertainties, providing plausible probabilistic P10 and P90 values. This range provides analysts with the capability of making informed strategic decisions that consider risk. Next, the model was applied to predict reserves (estimated ultimate recovery) and the underlying reservoir quality. These predictions were combined with unsupervised learning techniques (Gaussian Mixture Modelling), creating gas and oil sweet-spot maps. Finally, this workflow's robustness was demonstrated by artificially reducing data by 93%; indeed, the algorithm could reproduce the full-dataset results with a 71%-91% Pearson correlation, despite this reduction. Supporting this workflow creation is an evaluation of relevant research, data processing, feature engineering, documentation of the probabilistic ML structure, and discussion of model performance using systems analysis.

Download or read book Stretched Exponential Decline Model as a Probabilistic and Deterministic Tool for Production Forecasting and Reserve Estimation in Oil and Gas Shales written by Babak Akbarnejad Nesheli and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Today everyone seems to agree that ultra-low permeability and shale reservoirs have become the potentials to transform North America's oil and gas industry to a new phase. Unfortunately, transient flow is of long duration (perhaps life of the well) in ultra-low permeability reservoirs, and traditional decline curve analysis (DCA) models can lead to significantly over-optimistic production forecasts without additional safeguards. Stretched Exponential decline model (SEDM) gives considerably more stabilized production forecast than traditional DCA models and in this work it is shown that it produces unchanging EUR forecasts after only two-three years of production data are available in selected reservoirs, notably the Barnett Shale. For an individual well, the SEDM model parameters, can be determined by the method of least squares in various ways, but the inherent nonlinear character of the least squares problem cannot be bypassed. To assure a unique solution to the parameter estimation problem, this work suggests a physics-based regularization approach, based on critical velocity concept. Applied to selected Barnett Shale gas wells, the suggested method leads to reliable and consistent EURs. To further understand the interaction of the different fracture properties on reservoir response and production decline curve behavior, a series of Discrete Fracture Network (DFN) simulations were performed. Results show that at least a 3-layer model is required to reproduce the decline behavior as captured in the published SEDM parameters for Barnett Shale. Further, DFN modeling implies a large number of parameters like fracture density and fracture length are in such a way that their effect can be compensated by the other one. The results of DFN modeling of several Barnett Shale horizontal wells, with numerous fracture stages, showed a very good agreement with the estimated SEDM model for the same wells. Estimation of P90 reserves that meet SEC criteria is required by law for all companies that raise capital in the United States. Estimation of P50 and P10 reserves that meet SPE/WPC/AAPG/SPEE Petroleum Resources Management System (PRMS) criteria is important for internal resource inventories for most companies. In this work a systematic methodology was developed to quantify the range of uncertainty in production forecast using SEDM. This methodology can be used as a probabilistic tool to quantify P90, P50, and P10 reserves and hence might provide one possible way to satisfy the various legal and technical-society-suggested criteria.

Download or read book Fundamentals of Gas Shale Reservoirs written by Reza Rezaee and published by John Wiley & Sons. This book was released on 2015-07-01 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides comprehensive information about the key exploration, development and optimization concepts required for gas shale reservoirs Includes statistics about gas shale resources and countries that have shale gas potential Addresses the challenges that oil and gas industries may confront for gas shale reservoir exploration and development Introduces petrophysical analysis, rock physics, geomechanics and passive seismic methods for gas shale plays Details shale gas environmental issues and challenges, economic consideration for gas shale reservoirs Includes case studies of major producing gas shale formations

Download or read book Well Production Performance Analysis for Shale Gas Reservoirs written by Liehui Zhang and published by Elsevier. This book was released on 2019-05-16 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt: Well Production Performance Analysis for Shale Gas Reservoirs, Volume 66 presents tactics and discussions that are urgently needed by the petroleum community regarding unconventional oil and gas resources development and production. The book breaks down the mechanics of shale gas reservoirs and the use of mathematical models to analyze their performance. Features an in-depth analysis of shale gas horizontal fractured wells and how they differ from their conventional counterparts Includes detailed information on the testing of fractured horizontal wells before and after fracturing Offers in-depth analysis of numerical simulation and the importance of this tool for the development of shale gas reservoirs

Download or read book Proceedings of the International Field Exploration and Development Conference 2023 written by Jia’en Lin and published by Springer Nature. This book was released on with total page 1347 pages. Available in PDF, EPUB and Kindle. Book excerpt: