Topics involved in studies of the Earth's magnetic field and its secular variation range from the intricate observations of geomagnetism, to worldwide studies of archeomagnetism and paleomagnetism, through to the complex mathematics of dynamo theory. Traditionally these different aspects of geomagnetism have in the main been studied and presented in isolation from each other. This text draws together these lines of inquiry into an integrated framework to highlight the interrelationships and thus to provide a more comprehensive understanding of the geomagnetic field.
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.
Physics of Geomagnetic phenomena, Volume I covers the significant advances in geomagnetism and the penetrations into the generation of geomagnetic field phenomena. This volume is composed of three chapters. Chapter I deals briefly with the discovery and developments in geomagnetism, followed by discussions on some fundamental topics of the field, including the aurora and geomagnetic storms. This chapter also considers the instruments, geomagnetic stations, and the correlations between geomagnetic indices. Chapter II describes the magnetic properties of minerals and various processes of acquisition of remanent magnetization. This chapter also provides palaeomagnetic data for the direction and intensity of the geomagnetic field in ancient times. Chapter III explores geomagnetic variations caused by solar flares and eclipses. This book will prove useful to physicists, students in upper atmospheric and space topics, and scientists in allied fields with a background in geomagnetism.
Paleomagnetism is the study of the fossil magnetism in rocks. It has been paramount in determining that the continents have drifted over the surface of the Earth throughout geological time. The fossil magnetism preserved in the ocean floor has demonstrated how continental drift takes place through the process of sea-floor spreading. The methods and techniques used in paleomagnetic studies of continental rocks and of the ocean floor are described and then applied to determining horizontal movements of the Earth's crust over geological time. An up-to-date review of global paleomagnetic data enables 1000 million years of Earth history to be summarized in terms of the drift of the major crustal blocks over the surface of the Earth. The first edition of McElhinny's book was heralded as a "classic and definitive text." It thoroughly discussed the theory of geomagnetism, the geologic reversals of the Earth's magnetic field, and the shifting of magnetic poles. In the 25 years since the highly successful first edition of Palaeomagnetism and Plate Tectonics (Cambridge, 1973) the many advances in the concepts, methodology, and insights into paleomagnetism warrant this new treatment. This completely updated and revised edition of Paleomagnetism: Continents and Oceans will be a welcome resource for a broad audience of earth scientists as well as laypeople curious about magnetism, paleogeography, geology, and plate tectonics. Because the book is intended for a wide audience of geologists, geophysicists, and oceanographers, it balances the mathematical and descriptive aspects of each topic. - Details the theory and methodology of rock magnetism, with particular emphasis on intrepreting crustal movements from continental and oceanic measurements - Outlines Earth history for the past 1000 million years, from the Rodinia super-continent through its breakup and the formation of Gondwana to the formation and breakup of Pangea and the amalgamation of Eurasia - Provides a comprehensive treatment of oceanic paleomagnetism - Provides a set of color pateogeographic maps covering the past 250 million years - Written by two internationally recognized experts in the field
Electromagnetism and the Earth's Interior reviews the earth's magnetic fields in terms of physical processes that are occurring in the earth's interior. The book describes the distribution of the earth's magnetic field in terms of declination, horizontal intensity, and vertical intensity. The dynamo theory concerns the self-exciting electric generation in the interior of the earth, and can account for any geomagnetic secular variation. A workable laboratory model—a dynamo mechanism of Lowes and Wilkinson (1963) has a significant role on the dynamo theory for the model actually demonstrated Herzenberg's proof that was developed mathematically. The text also describes various aspects of long-term geomagnetic variations, such as the decrease in the dipole moment, the reversal of the geomagnetic field, the drift of eccentric dipole, the fluctuation in the length of day, and the geomagnetic secular variation. The book also investigates the possible effects of the ocean on geomagnetic variations. The characteristics of transient geomagnetic variations on islands can point to a possible special underground structure. The book is suitable for geologists, astrophysicists, seismologists, and students of the natural sciences.
Electric currents are fundamental to the structure and dynamics of space plasmas, including our own near-Earth space environment, or “geospace.”This volume takes an integrated approach to the subject of electric currents by incorporating their phenomenology and physics for many regions in one volume. It covers a broad range of topics from the pioneers of electric currents in outer space, to measurement and analysis techniques, and the many types of electric currents. First volume on electric currents in space in over a decade that provides authoritative up-to-date insight on the current status of research Reviews recent advances in observations, simulation, and theory of electric currents Provides comparative overviews of electric currents in the space environments of different astronomical bodies Electric Currents in Geospace and Beyond serves as an excellent reference volume for a broad community of space scientists, astronomers, and astrophysicists who are studying space plasmas in the solar system. Read an interview with the editors to find out more: https://eos.org/editors-vox/electric-currents-in-outer-space-run-the-show
This reference encompasses the fields of Geomagnetism and Paleomagnetism in a single volume. Both sciences have applications in navigation, in the search for minerals and hydrocarbons, in dating rock sequences, and in unraveling past geologic movements such as plate motions they have contributed to a better understanding of the Earth. The book describes in fine detail the current state of knowledge and provides an up-to-date synthesis of the most basic concepts. It is an indispensable working tool not only for geophysicists and geophysics students but also for geologists, physicists, atmospheric and environmental scientists, and engineers.
"This book by Lisa Tauxe and others is a marvelous tool for education and research in Paleomagnetism. Many students in the U.S. and around the world will welcome this publication, which was previously only available via the Internet. Professor Tauxe has performed a service for teaching and research that is utterly unique."—Neil D. Opdyke, University of Florida
