Electromagnetic Methods in Applied Geophysics


Book Description

As a slag heap, the result of strip mining, creeps closer to his house in the Ohio hills, fifteen-year-old M. C. is torn between trying to get his family away and fighting for the home they love.







Foundations of Geophysical Electromagnetic Theory and Methods


Book Description

Foundations of Geophysical Electromagnetic Theory and Methods, Second Edition, builds on the strength of the first edition to offer a systematic exposition of geophysical electromagnetic theory and methods. This new edition highlights progress made over the last decade, with a special focus on recent advances in marine and airborne electromagnetic methods. Also included are recent case histories on practical applications in tectonic studies, mineral exploration, environmental studies and off-shore hydrocarbon exploration. The book is ideal for geoscientists working in all areas of geophysics, including exploration geophysics and applied physics, as well as graduate students and researchers working in the field of electromagnetic theory and methods. - Presents theoretical and methodological foundations of geophysical field theory - Synthesizes fundamental theory and the most recent achievements of electromagnetic (EM) geophysical methods in the framework of a unified systematic exposition - Offers a unique breadth and completeness in providing a general picture of the current state-of-the-art in EM geophysical technology - Discusses practical aspects of EM exploration for mineral and energy resources




Computational Methods in Geophysical Electromagnetics


Book Description

This monograph provides a framework for students and practitioners who are working on the solution of electromagnetic imaging in geophysics. Bridging the gap between theory and practical applied material (for example, inverse and forward problems), it provides a simple explanation of finite volume discretization, basic concepts in solving inverse problems through optimization, a summary of applied electromagnetics methods, and MATLAB??code for efficient computation.




Geophysical Electromagnetic Theory and Methods


Book Description

In this book the author presents the state-of-the-art electromagnetic (EM)theories and methods employed in EM geophysical exploration.The book brings together the fundamental theory of EM fields and the practicalaspects of EM exploration for mineral and energy resources.This text is unique in its breadth and completeness in providing anoverview of EM geophysical exploration technology. The book is divided into four parts covering the foundations of EMfield theory and its applications, and emerging geophysical methods.Part I is an introduction to the field theory required for baselineunderstanding. Part II is an overview of all the basic elements ofgeophysical EM theory, from Maxwell's fundamental equations to modernmethods of modeling the EM field in complex 3-D geoelectrical formations. Part III deals with the regularized solution of ill-posedinverse electromagnetic problems, the multidimensional migration and imaging ofelectromagnetic data, and general interpretation techniques. Part IV describes major geophysical electromagnetic methods—direct current (DC), induced polarization (IP), magnetotelluric(MT), and controlled-source electromagnetic (CSEM) methods—and covers different applications of EM methods in exploration geophysics, includingminerals and HC exploration, environmental study, and crustal study. - Presents theoretical and methodological findings, as well as examples of applications of recently developed algorithms and software in solving practical problems - Describes the practical importance of electromagnetic data through enabling discussions on a construction of a closed technological cycle, processing, analysis and three-dimensional interpretation - Updates current findings in the field, especially with MT, magnetovariational and seismo-electrical methods and the practice of 3D interpretations




Applied Geophysics


Book Description

This is the completely revised and updated version of the popular and highly regarded textbook, Applied Geophysics. It describes the physical methods involved in exploration for hydrocarbons and minerals, which include gravity, magnetic, seismic, electrical, electromagnetic, radioactivity, and well-logging methods. All aspects of these methods are described, including basic theory, field equipment, techniques of data acquisition, data processing and interpretation, with the objective of locating commercial deposits of minerals, oil, and gas and determining their extent. In the fourteen years or so since the first edition of Applied Geophysics, many changes have taken place in this field, mainly as the result of new techniques, better instrumentation, and increased use of computers in the field and in the interpretation of data. The authors describe these changes in considerable detail, including improved methods of solving the inverse problem, specialized seismic methods, magnetotellurics as a practical exploration method, time-domain electromagnetic methods, increased use of gamma-ray spectrometers, and improved well-logging methods and interpretation.




Principles of Applied Geophysics


Book Description

The welcome accorded to the first two editions of this book has been most encouraging. The object of the third edition continues to be to give a brief but "fairly comprehensive survey of the methods of applied geophysics including some of the modern interpretation techniques. The general approach and plan of the previous editions are preserved, but in bringing the book up to date some changes have been made to which I would like to draw the reader's special attention. SI units are strictly adhered to except in six illustrative figures reproduced from older literature and left intact to save some extensive redraughting. Following the recommendation of the International Union of Geodesy and Geophysics, the magnetic field measured in geophysical work is labelled here as flux density (tesla). Consequently, the symbols H, Z and T commonly used in geomagnetic work should stand for flux density. In the Max wellian theory of electromagnetism the symbol H stands, by convention, for a magnetizing force (A m -1) and a discerning reader will at once sense a source of confusion. This source of confusion is avoided in the present edition by B , B and B instead of H, Z and T. The employing the symbols b z t latter ~et is employed for the corresponding magnetizing forces of the earth's field. I hope this notation will gain general acceptance because it so easily dispenses with an ambiguity that otherwise tends to lead to unnecessary confusion of units and dimensions in geomagnetism.




The Magnetotelluric Method


Book Description

The magnetotelluric method is a technique for imaging the electrical conductivity and structure of the Earth, from the near surface down to the 410 km transition zone and beyond. This book forms the first comprehensive overview of magnetotellurics, from the salient physics and its mathematical representation to practical implementation in the field, data processing, modeling and geological interpretation. Electromagnetic induction in 1-D, 2-D and 3-D media is explored, building from first principles, and with thorough coverage of the practical techniques of time series processing, distortion, numerical modeling and inversion. The fundamental principles are illustrated with a series of case histories describing geological applications. Technical issues, instrumentation and field practices are described for both land and marine surveys. This book provides a rigorous introduction to magnetotellurics for academic researchers and advanced students, and will be of interest to industrial practitioners and geoscientists wanting to incorporate rock conductivity into their interpretations.




Natural Electromagnetic Fields in Pure and Applied Geophysics


Book Description

This research monograph presents all the branches of geophysics based on natural electromagnetic fields and their associated subjects. Meant for postgraduate and research level courses, it includes research guidance and collection of magnetotelluric data in some parts of Eastern India and their qualitative and quantitative interpretation. Specific topics highlighted include (i) Electrotellurics, (ii) Magnetotellurics, (iii) Geomagnetic Depth Sounding and Magnetometer Array Studies, (iv) Audio Frequency Magnetotellurics and Magnetic Methods, (v) Marine Magnetotelluric and Marine Controlled Source Electromagnetic Methods, (vi) Electrical Conductivity of Rocks and Minerals and (vii) Mathematical Modelling and Some Topics on Inversion needed for Interpretation of Geoelectrical Data.




Introduction to Controlled-Source Electromagnetic Methods


Book Description

An introduction to the theory and practical application of CSEM methods to explore whether subsurface structures contain hydrocarbons.