Acoustic Waves In Boreholes

Introducing the first, self-contained reference on acoustic waveform logging Acoustic measurements in boreholes were first made as a specialized logging technique in geological exploration, but recent advances have greatly expanded the potential applications of this technique. Acoustic Waves in Boreholes provides a thorough review of the theory and interpretation techniques needed to realize these applications, emphasizing the role of guided modes and critically refracted waves in determining the characteristics of recorded waveforms. Topics covered in this comprehensive volume include the seismic properties of rocks; propagation of axisymmetric waves along fluid-filled boreholes in isotropic rocks; and symmetric and nonsymmetric sources in isotropic, transversely isotropic, and porous, permeable formations in open and cased boreholes. Each chapter includes the theory of synthetic microseismogram computation, interpretation and data inversion techniques illustrated using computed seismograms, and case histories using experimental data. Appendices providing the mathematical formulation needed to compute microseismograms, with a single consistent notation used throughout, are also included in appropriate chapters. The wide range of geomechanical properties covered in this book will interest exploration geophysicists, reservoir engineers, civil engineers, geologists, and soil scientists.

Introducing the first, self-contained reference on acoustic waveform logging Acoustic measurements in boreholes were first made as a specialized logging technique in geological exploration, but recent advances have greatly expanded the potential applications of this technique. Acoustic Waves in Boreholes provides a thorough review of the theory and interpretation techniques needed to realize these applications, emphasizing the role of guided modes and critically refracted waves in determining the characteristics of recorded waveforms. Topics covered in this comprehensive volume include the seismic properties of rocks; propagation of axisymmetric waves along fluid-filled boreholes in isotropic rocks; and symmetric and nonsymmetric sources in isotropic, transversely isotropic, and porous, permeable formations in open and cased boreholes. Each chapter includes the theory of synthetic microseismogram computation, interpretation and data inversion techniques illustrated using computed seismograms, and case histories using experimental data. Appendices providing the mathematical formulation needed to compute microseismograms, with a single consistent notation used throughout, are also included in appropriate chapters. The wide range of geomechanical properties covered in this book will interest exploration geophysicists, reservoir engineers, civil engineers, geologists, and soil scientists.

Acoustic logging is a multidisciplinary technology involving basic theory, instrumentation, and data processing/interpretation methodologies. The advancement of the technology now allows for a broad range of measurements to obtain formation properties such as elastic wave velocity and attenuation, formation permeability, and seismic anisotropy that are important for petroleum reservoir exploration. With these advances, it is easier to detect and characterize formation fractures, estimate formation stress field, and locate/estimate petroleum reserves. The technology has evolved from the monopole acoustic logging into the multipole, including dipole, cross-dipole, and even quadrupole, acoustic logging measurements. The measurement process has developed from the conventional wireline logging into the logging-while-drilling stage. For such a fast developing technology with applications that are interesting to readers of different backgrounds, it is necessary to have systematic documentation of the discipline, including the theory, methods, and applications, as well as the technology's past, present, and near future development trends. Quantitative Borehole Acoustic Methods provides such documentation, with emphasis on the development over the past decade. Although considerable effort has been made to provide a thorough basis for the theory and methodology development, emphasis is placed on the applications of the developed methods. The applications are illustrated with field data examples. Many of the acoustic waveform analysis/processing methods described in the book are now widely used in the well logging industry.

Provides an overview of the sensitivity of elastic waves in the earth to in situ stress, pore pressure, and the anisotropy of the rock fabric. A variety of applications and real data examples is presented, with particular emphasis placed on the rock-physics basis underlying the use of geophysical data for solving geomechanical problems.

This book covers the principles, historical development, and applications of many acoustic logging methods, including acoustic logging-while-drilling and cased-hole logging methods. Benefiting from the rapid development of information technology, the subsurface energy resource industry is moving toward data integration to increase the efficiency of decision making through the use of advanced big data and artificial intelligence technologies, such as machine/deep learning. However, wellbore failure may happen if evaluations of risk and infrastructure are made using data mining methods without a complete understanding of the physics of borehole measurements. Processed results from borehole acoustic logging will constitute part of the input data used for data integration. Therefore, to successfully employ modern techniques for data assimilation and analysis, one must fully understand the complexity of wave mode propagation, how such propagation is influenced by the well, and the materials placed within the well (i.e., the cement, casing, and drill strings), and ultimately how waves penetrate into and are influenced by geological formations. State-of-the-art simulation methods, such as the discrete wavenumber integration method (DWM) and the finite difference method (FDM), are introduced to tackle the numerical challenges associated with models containing large material contrasts, such as the contrasts between borehole fluids and steel casings. Waveforms and pressure snapshots are shown to help the reader understand the wavefields under various conditions. Advanced data processing methods, including velocity analyses within the time and frequency domains, are utilized to extract the velocities of different modes. Furthermore, the authors discuss how various formation parameters influence the waveforms recorded in the borehole and describe the principles of both existing and potential tool designs and data acquisition schemes. This book greatly benefits from the research and knowledge generated over four decades at the Earth Resources Laboratory (ERL) of the Massachusetts Institute of Technology (MIT) under its acoustic logging program. Given its scope, the book is of interest to geophysicists (including borehole geophysicists and seismologists), petrophysicists, and petroleum engineers who are interested in formation evaluation and cementation conditions. In addition, this book is of interest to researchers in the acoustic sciences and to 4th-year undergraduate and postgraduate students in the areas of geophysics and acoustical physics.

Approaches that are typically applied in deep exploration geophysics, combining different seismic and logging methods, can be technically adapted for certain geotechnical or hydrogeological surveys or some site characterizations in the framework of seismic hazard studies. Currently it is entirely feasible to implement this type of geophysical surveying if the situation requires. After reviewing the current state of knowledge regarding borehole measurements of subsurface shear velocities applied to the geotechnical field, this book illustrates the feasibility of carrying out vertical seismic profiles (VSPs) and logs in this field. This approach also illustrates the value of combining velocity measurements of formations provided by borehole seismic tools (VSP) and acoustic (sonic) tools. An innovative example of the application of borehole seismic and logging methods is then presented in the case study of a relatively near-surface (from 20 to 130 m) karst carbonate aquifer. It shows how a multi-scale description of the reservoir can be carried out by integrating the information provided by different 3D-THR surface seismic methods, full waveform acoustic logging, VSP with hydrophones, borehole optical televiewer and flow measurements. In this book the authors provide readers with guidelines to carry out these operations, in terms of acquisitions as well as processing and interpretation. Thus, users will be able to draw inspiration to continue transferring petroleum techniques and other innovative methods for use in near-surface studies.

Seismoelectric coupling and its current and potential future applications The seismoelectric method—the naturally-occurring coupling of seismic waves to electromagnetic fields—can provide insight into important properties of porous media. With a variety of potential environmental and engineering uses, as well as larger scale applications such as earthquake detection and oil and gas exploration, it offers a number of advantages over conventional geophysical methods. Seismoelectric Exploration: Theory, Experiments, and Applications explores the coupling between poroelastic and electromagnetic disturbances, discussing laboratory experiments, numerical modeling techniques, recent theoretical developments, and field studies. Volume highlights include: Physics of the seismoelectric effect at the microscale Governing equations describing coupled seismo-electromagnetic fields Examples of successful seismoelectric field experiments in different geological settings Current and potential applications of seismoelectric coupling Noise removal techniques for seismoelectric field measurements The American Geophysical Union promotes discovery in Earth and space science for the benefit of humanity. Its publications disseminate scientific knowledge and provide resources for researchers, students, and professionals.

The Handbook of Borehole Acoustics and Rock Physics for Reservoir Characterization combines in a single useful handbook the multidisciplinary domains of the petroleum industry, including the fundamental concepts of rock physics, acoustic logging, waveform processing, and geophysical application modeling through graphical examples derived from field data. It includes results from core studies, together with graphics that validate and support the modeling process, and explores all possible facets of acoustic applications in reservoir evaluation for hydrocarbon exploration, development, and drilling support. The Handbook of Borehole Acoustics and Rock Physics for Reservoir Characterization serves as a technical guide and research reference for oil and gas professionals, scientists, and students in the multidisciplinary field of reservoir characterization through the use of petrosonics. It overviews the fundamentals of borehole acoustics and rock physics, with a focus on reservoir evaluation applications, explores current advancements through updated research, and identifies areas of future growth. Presents theory, application, and limitations of borehole acoustics and rock physics through field examples and case studies Features "Petrosonic Workflows" for various acoustic applications and evaluations, which can be easily adapted for practical reservoir modeling and interpretation Covers the potential advantages of acoustic-based techniques and summarizes key results for easy geophysical application