Induction Soundings of the Earth's Mantle


Book Description

At the heart of this book is the generalized theoretical approach that is applied to investigate the geoelectrical structure of the Earth’s mantle. It also analyzes the results of regional and global induction sounding of the Earth’s mantle and compares them with the results obtained by other geophysical methods. The generalized theoretical approach employs the Induction Law as a basis for identifying extended relations between magnetic field components, including their plane divergence, impedances and spatial derivatives. The estimations of impedance values and spatial derivatives are performed using the theory of stochastic processes. The book also considers the external sources of magnetic fields used for sounding the Earths mantle from the modern theory perspective, as well as the problem of coincidence of magneto-variation and magnetotelluric methods. Further, it discusses secular variations in the Earth’s resistance caused by non-induction sources, factors that are correlated with the number of earthquakes in the region and shifted in time with global indexes. It is a valuable resource for scientists applying deep induction soundings or interested in the structures of and processes in the Earth’s interior.




Electrical Properties of the Earth’s Mantle


Book Description

Table 1 Earth conductivity profiles Figure File Name Apx. Depth Remarks References 1. Global Models 1939-69 LAPR39 0--1250 global Sq, Dst LAHIRI and PRICE, 1939; PRICE, 1973 RIKI50 0--1400 misc. data sources RIKITAKE. 1950; 1966 MCD057 0--2900 LAPR39 + secular change McDoNALD, 1957 CANT60 100--600 see ECKHARDT et a!. , 1963 CANTWELL, 1960 YUKU65 380--1900 ring current YUKUTAKE, 1965 BANK69 0--1700 ring current BANKS, 1969; 1972 2. Global Models 1970--74 BFRS70 100--700 Sq, Dst 27-d variations BERDICHEVSKY et a!. , 1970; 1973 PRKR70 0--3200 rework BANKS, 1969, data PARKER, 1970 SCJA72 0--1000 pulsations, bays, Sq, Dst SCHMUCKER and JANKOWSKI, 1972 BANK72 230--1250 model summary BANKS, 1972 JADY74 0--2951 Sq, 27-d, annual variations JADY, 1974 FAR074 300--1500 with BFRS70 FAINBERG and ROTANOVA, 1974 SCHM74 0--1000 see HAAK, 1980 SCHMUCKER, 1974 DMRB77 0--1450 all available data DMITRIEV et al. , 1977 Global Models 1974-1983 3. PRKN74 60-430 Sq PARKINSON, 1974 DUCM80 0--2900 annual means DUCRUIX et a!. , 1980 ISIK80 320--2020 Sq, Dst, annual, solar cycle ISIKARA, 1980 ACMC81 0--2875 secular impulse ACACHE et a!. , 1980 ROKI82 350--1200 various methods ROKITYANSKY. 1982 JAPA83 0--1200 Dst JADY and PATERSON, 1983 4. Pacific Models LAUN74 0--500 near Calif. ; see DRURY, 1978 LAUNAY, 1975 LARSEN, 1975 LAHA75 0--800 Hawaii 7-1350 FILL80 NE Pacific FILLOUX, 1980 LAW and GREENHOUSE, LWGR81 0--200 Juan de Fuca 1981 0--250 Juan de Fuca OLDENBURG et a!. , 1984 OLJA84 OLCA84 0-250 near Calif. OLDENBURG et al. , 1984 OLNC84 0--250 N. cent. Pacific OLDENBURG et ai.




Electromagnetic Sounding of the Earth's Interior


Book Description

Based on lectures given in the First Russian School-Seminar on electromagnetic soundings of the Earth held in Moscow on 15th November, 2003, this book acquaints scientists and technologists with the latest achievements in theory, techniques and practical applications of the methods of electromagnetic sounding. This three part text covers the methods considered for Earth electromagnetic sounding on a global, regional, and local scale; modern methods for solving forward and inverse problems of geoelectrics, particularily contemporary approaches to the EM data modeling and interpretation in the class of three-dimensional models; and the results of regional EM on-land and sea soundings * 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-electriccal methods and the practice of 3D interpretaions




Geoelectromagnetic Investigation of the Earth’s Crust and Mantle


Book Description

Electrical conductivity is a parameter which characterizes composition and physical state of the Earth's interior. Studies of the state equations of solids at high temperature and pressure indicate that there is a close relation be tween the electrical conductivity of rocks and temperature. Therefore, measurements of deep conductivity can provide knowledge of the present state and temperature of the Earth's crust and upper mantle matter. Infor mation about the temperature of the Earth's interior in the remote past is derived from heat flow data. Experimental investigation of water-containing rocks has revealed a pronounced increase of electrical conductivity in the temperature range D from 500 to 700 DC which may be attributed to the beginning of fractional melting. Hence, anomalies of electrical conductivity may be helpful in identitying zones of melting and dehydration. The studies of these zones are perspective in the scientific research of the mobile areas of the Earth's crust and upper mantle where tectonic movements, processes ofthe region al metamorphism and of forming mineral deposits are most intensive. Thus, in the whole set of research on physics of the Earth the studies of electrical conductivity of deep-seated rocks appear, beyond doubt, very important.




Encyclopedia of Geomagnetism and Paleomagnetism


Book Description

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.










Water in Nominally Anhydrous Minerals


Book Description

Volume 62 of Reviews in Mineralogy and Geochemistry reviews the recent research in the geochemistry and mineral physics of hydrogen in the principal mineral phases of the Earth's crust and mantle. Contents: Analytical Methods for Measuring Water in Nominally Anhydrous Minerals The Structure of Hydrous Species in Nominally Anhydrous Minerals: Information from Polarized IR Spectroscopy Structural Studies of OH in Nominally Anhydrous Minerals Using NMR Atomistic Models of OH Defects in Nominally Anhydrous Minerals Hydrogen in High Pressure Silicate and Oxide Mineral Structures Water in Nominally Anhydrous Crustal Minerals: Speciation, Concentration, and Geologic Significance Water in Natural Mantle Minerals I: Pyroxenes Water in Natural Mantle Minerals II: Olivine, Garnet and Accessory Minerals Thermodynamics of Water Solubility and Partitioning The Partitioning of Water Between Nominally Anhydrous Minerals and Silicate Melts The Stability of Hydrous Mantle Phases Hydrous Phases and Water Transport in the Subducting Slab Diffusion of Hydrogen in Minerals Effect of Water on the Equation of State of Nominally Anhydrous Minerals Remote Sensing of Hydrogen in Earth's Mantle




Folding and Fracturing of Rocks


Book Description

This Special Publication is a celebration of research into the Folding and Fracturing of Rocks to mark the 50th anniversary of the publication of the seminal textbook by J. G. Ramsay. Folding and Fracturing of Rocks summarised the key structural geology concepts of the time. Through his numerical and geometric focus John pioneered and provided solutions to understanding the processes leading to the folding and fracturing of rocks. His strong belief that numerical and geometric solutions, to understanding crustal processes, should be tested against field examples added weight and clarity to his work. The basic ideas and solutions presented in the text are as relevant now as they were 50 years ago, and this collection of papers celebrates John’s contribution to structural geology. The papers explore the lasting impact of John and his work, they present case studies and a modern understanding of the process documented in the Folding and Fracturing of Rocks.




Potential Theory in Applied Geophysics


Book Description

This book introduces the principles of gravitational, magnetic, electrostatic, direct current electrical and electromagnetic fields, with detailed solutions of Laplace and electromagnetic wave equations by the method of separation of variables. Discussion includes behaviours of the scalar and vector potential and the nature of the solutions of these boundary value problems, along with the use of complex variables and conformal transformation, Green's theorem, Green's formula and Green's functions.