The Vibroseis source

Introduction. The Wavefield of a Surface Source in a Horizontally Layered Elastic Medium. Configuration. Basic relations. Decomposition into upgoing and downgoing wavefields. The local reflection of the wavefield at a layer interface. The propagation of the wavefield within a single layer. The global reflection response. The particle velocity and traction components at an arbitrary point in the medium. The transformation to the space domain. The elastic halfspace. The horizontally layered acoustic medium. Far field relations. The Seismic Vibrator. Mechanics of the land vibrator. The vibrator signal. The baseplate behaviour. The Combined Earth-Vibrator Model. The earth model. The combined earth-vibrator model. The numerical procedure. Numerical results. Test of the Theory By Experiment. The data set. The earth model. The vibrator model. The feedback signal on the seismic vibrator. The Marine Vibrator Source. Configuration. Vibroseis: land and marine. The earth model. The mechanical model of the marine vibrator. The combined earth-vibrator model. The numerical procedure. The distribution of pressure and displacement at the surface of the vibrator. The average power factor. Far field relations. Test of the theory by experiment. Processing of Vibroseis data. Description of the data set. Conventional processing. Proposed processing sequence. Concluding remarks. Appendices: Determination of Green's Matrices for Acoustic and Elastic Media. Solution of the Differential Equation Describing the Plate Bending. The Numerical Procedure for the Combined Earth-Vibrator Model. References. Author Index. Subject Index.