Scientific understanding of fluid flow in rock fractures--a process underlying contemporary earth science problems from the search for petroleum to the controversy over nuclear waste storage--has grown significantly in the past 20 years. This volume presents a comprehensive report on the state of the field, with an interdisciplinary viewpoint, case studies of fracture sites, illustrations, conclusions, and research recommendations. The book addresses these questions: How can fractures that are significant hydraulic conductors be identified, located, and characterized? How do flow and transport occur in fracture systems? How can changes in fracture systems be predicted and controlled? Among other topics, the committee provides a geomechanical understanding of fracture formation, reviews methods for detecting subsurface fractures, and looks at the use of hydraulic and tracer tests to investigate fluid flow. The volume examines the state of conceptual and mathematical modeling, and it provides a useful framework for understanding the complexity of fracture changes that occur during fluid pumping and other engineering practices. With a practical and multidisciplinary outlook, this volume will be welcomed by geologists, petroleum geologists, geoengineers, geophysicists, hydrologists, researchers, educators and students in these fields, and public officials involved in geological projects.

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.