Practical Magnetotellurics
Contributors: Bahr, Karsten
Publisher: Cambridge University Press
Published: 2005
Place of publication: Cambridge
Language: eng
Format: [electronic resource]
Number of pages: 272
ISBN-13: 9780511079955; 9780511614095
Subjects: Magnetotelluric prospecting; Engineering; Mining engineering
Description: The first book to describe the practical aspects of the magnetotelluric method in detail.
Notes: Over-interpretation of transfer function amplitudes.

Description based on print version record.
Table of contents: title: Cover; Half-title; Title; Copyright; Contents; Preface; Symbols; Chapter 1 Introduction; 1.1 Magnetotellurics as a passive electromagnetic exploration method and its relation to active electromagnetic and ... ; 1.2 Problems for which EM studies are useful: a first overview of conduction mechanisms; 1.3 An historical perspective; 1.4 MTnet; 1.5 Books that cover other aspects of EM; Chapter 2 Basic theoretical concepts; 2.1 Assumptions of the MT method; 2.2 Time invariance as a consequence of the plane wave assumption; 2.3 Why EM speaks volumes: MT as a vector field method.; title: 2.4 The concepts of transfer function and penetration depth2.5 Induction in a layered half-space: the concept of apparent resistivity and phase; 2.6 Induction at a discontinuity: a simple two-dimensional (2-D) world and the concept of E- and B-polarisation; 2.7 Adjustment length; 2.8 Induction arrows; 2.9 The impedance tensor and a preview of three-dimensionality; Chapter 3 Planning a field campaign; 3.1 Target depths and choosing the right sensors and equipment; 3.1.1 Considering the period range; 3.1.2 Magnetic sensors; 3.1.3 Electric field sensors; 3.1.4 Data-acquisition systems.; title: 3.2 Target area and spatial aliasing3.3 Arrays versus profiles: further considerations of dimensionality; 3.4 Resolving power and the duration of a campaign; 3.5 Sources of noise external to the Earth and a preview of processing schemes; 3.6 Economic considerations; 3.7 Suggested checklist of field items; 3.8 A step-by-step guide to installing an MT station; Chapter 4 From time series to transfer functions: data processing; 4.1 Fourier transformation, calibration and the spectral matrix; 4.2 Least square, remote reference and robust estimation of transfer functions.; title: 4.3 'Upwards' and 'downwards' biased estimates4.4 Displaying the data and other deceptions; 4.5 Through data interpolation to pseudosections; 4.6 Pseudosections versus Cartesian graphs; Chapter 5 Dimensionality and distortion; 5.1 The discontinuity revisited: the concept of static shift; 5.2 Rotating the impedance tensor; 5.4 A parade of general models and their misfit measures; 5.4 Problems with decoupling E- and B-polarisations: farewell to the 2-D world; 5.5 Decomposition as an hypothesis test: avoiding the black-box syndrome; 5.6 How many strike directions are there?; title: 5.7 The concepts of anisotropy, skew bumps, and strike decoupling5.8 Static shift, the long and the short of it: 'correcting' or modelling?; 5.9 Current channelling and the concept of magnetic distortion; Chapter 6 Numerical forward modelling; 6.1 Why forward modelling, and which scheme?; 6.2 Practical numerical modelling: gridding rules, boundary conditions, and misfits revisited; 6.2.1 Gridding rules and boundary conditions; 6.2.2 Misfits revisited; 6.3 From computed electric and magnetic fields to transfer functions; 6.4 Avoiding common mistakes; Too complicated a start model.