Pressure Transient Formation And Well Testing

This reference presents a comprehensive description of flow through porous media and solutions to pressure diffusion problems in homogenous, layered, and heterogeneous reservoirs. It covers the fundamentals of interpretation techniques for formation tester pressure gradients, and pretests, multiprobe and packer pressure transient tests, including derivative, convolution, and pressure-rate and pressure-pressure deconvolution. Emphasis is placed on the maximum likelihood method that enables one to estimate error variances in pressure data along with the unknown formation parameters. Serves as a training manual for geologists, petrophysicists, and reservoir engineers on formation and pressure transient testing Offers interpretation techniques for immediate application in the field Provides detailed coverage of pretests, multiprobe and packer pressure transient tests, including derivative, convolution, and pressure-rate and pressure-pressure deconvolution

Pressure Transient Testing presents the fundamentals of pressure-transient test analysis and design in clear, simple language and explains the theoretical bases of commercial well-test-analysis software. Test-analysis techniques are illustrated with complete and clearly written examples. Additional exercises for classroom or individual practice are provided. With its focus on physical processes and mathematical interpretation, this book appeals to all levels of engineers who want to understand how modern approaches work. Pressure transient test analysis is a mature technology in petroleum engineering; even so, it continues to evolve. Because of the developments in this technology since the last SPE textbook devoted to transient testing was published, we concluded that students could benefit from a textbook approach to the subject that includes a representative sampling of the more important fundamentals and applications. We deliberately distinguish between a textbook approach, which stresses understanding through numerous examples and exercises dealing with selected fundamentals and applications, and a monograph approach, which attempts to summarize the state-of-the-art in the technology. Computational methods that transient test analysts use have gone through a revolution since most existing texts on the subject were written. Most calculations are now done with commercial software or by spreadsheets or proprietary software developed by users to meet personal needs and objectives. These advances in software have greatly increased productivity in this technology, but they also have contributed to a "black box" approach to test analysis. In this text, we attempt to explain what's in the box, and we do not include a number of the modern tools that enhance individual engineer productivity. We hope, instead, to provide understanding so that the student can use the commercial software with greater appreciation and so that the student can read monographs and papers on transient testing with greater appreciation for the context of the subject. Accordingly, this text is but an introduction to the vast field of pressure transient test analysis.

Well Test Analysis for Multilayered Reservoirs with Formation Crossflow introduces the fundamentals of well test analysis of a multilayered reservoir with formation crossflow. The effects of reservoir parameters on wellbore pressure and flow rate are examined, as is a proper method that has been established to analyze well test data that leads to better determinations on the reservoir parameters for each layer of the reservoir. Focusing on multilayer models for data analysis, this reference explains the reasons for the existence of single-phase crossflow in multilayer reservoirs, exploring methods to establish them and presenting practical applications to utilize and implement for today’s more complex reservoirs. Aiding in better well testing operations and models, this book is a one-stop solution for today’s reservoir and production engineer, helping them understand every layer of their reservoir. Includes real-world examples of well testing through multilayered reservoirs, whether with crossflow or with formation crossflow Provides strong guidance and criteria of research on reservoir dynamic performance, such as physical models and mathematical models Includes a new unsteady crossflow model for vertical interference testing in low-permeability zones Describes interpretation methods for different cases in multilayer reservoirs, including a new model called semipermeable walls for stratified reservoirs, drawdown test procedures and layer-by-layer test procedures that are useful for shales between layers

This book on well test analysis, and the use of advanced interpretation models is volume 3 in the series Handbook of Petroleum Exploration and Production. The chapters in the book are: Principles of Transient Testing, Analysis Methods, Wellbore Conditions, Effect of Reservoir Heterogeneities on Well Responses, Effect of Reservoir Boundaries on Well Responses, Multiple Well Testing, Application to Gas Reservoirs, Application to Multiphase Reservoirs, Special Tests, Practical Aspects of Well Test Interpretation.

Traditional well logging methods, such as resistivity, acoustic, nuclear and NMR, provide indirect information related to fluid and formation properties. The “formation tester,” offered in wireline and MWD/LWD operations, is different. It collects actual downhole fluid samples for surface analysis, and through pressure transient analysis, provides direct measurements for pore pressure, mobility, permeability and anisotropy. These are vital to real-time drilling safety, geosteering, hydraulic fracturing and economic analysis. Methods for formation testing analysis, while commercially important and accounting for a substantial part of service company profits, however, are shrouded in secrecy. Unfortunately, many are poorly constructed, and because details are not available, industry researchers are not able to improve upon them. This new book explains conventional models and develops new powerful algorithms for “double-drawdown” and “advanced phase delay” early-time analysis - importantly, it is now possible to predict both horizontal and vertical permeabilities, plus pore pressure, within seconds of well logging in very low mobility reservoirs. Other subjects including inertial Forchheimer effects in contamination modeling and time-dependent flowline volumes are also developed. All of the methods are explained in complete detail. Equations are offered for users to incorporate in their own models, but convenient, easy-to-use software is available for those needing immediate answers. The leading author is a well known petrophysicist, with hands-on experience at Schlumberger, Halliburton, BP Exploration and other companies. His work is used commercially at major oil service companies, and important extensions to his formation testing models have been supported by prestigious grants from the United States Department of Energy. His new collaboration with China National Offshore Oil Corporation marks an important turning point, where advanced simulation models and hardware are evolving side-by-side to define a new generation of formation testing logging instruments. The present book provides more than formulations and solutions: it offers a close look at formation tester development “behind the scenes,” as the China National Offshore Oil Corporation opens up its research, engineering and manufacturing facilities through a collection of interesting photographs to show how formation testing tools are developed from start to finish.

The book comprises two parts: Pressure and Flow Well Testing (Part I) and Temperature Well Testing (Part II), and contains numerous authors’ developments. Due to the similarity in Darcy’s and Fourier’s laws the same differential diffusivity equation describes the transient flow of incompressible fluid in porous medium and heat conduction in solids. Therefore it is reasonable to assume that the techniques and data processing procedures of pressure well tests can be applied to temperature well tests. The book presents new methods to determine the formation of permeability and skin factors from tests conducted in simulated wells, designing interference well tests, processing constant bottom-hole pressure tests, estimation of the formation temperature and geothermal gradients from temperature surveys and logs, in-situ determination of the formation thermal conductivity and contact thermal resistance of boreholes, temperature regime of boreholes (cementing of production liners), and the recovery of thermal equilibrium in deep and superdeep wells. Processing and analysis of pressure and geothermal data are shown on numerous field examples from different regions of the world. The book is intended for students, engineers, and researchers in the field of hydrocarbon geophysics and geology, groundwater searching and exploitation, and subsurface environment examination. It will be also useful for specialists studying pressure and temperature in parametric deep and superdeep wells.