Computation of Datum Static Corrections
For many geophysicists, the computation of datum static corrections means looking up or remembering appropriate formulas and applying these to the relevant variables for the line surveyed. The objective here is to present the topic in such a way that readers can visualize the methodology so that whenever datum static correction formulas are needed, they can be constructed easily from basic principles. The various formulas are composed of simple elements that require several parameters relating to the near surface-elevation, thickness, and velocity.
Figures & Tables
Static corrections for seismic reflection surveys
“This reference manual is designed to enable more geophysicists to appreciate static corrections, especially their limitations, their relationship with near-surface geology, and their impact on the quality of final interpreted sections. The book is addressed to those involved in data acquisition (datum static corrections), data processing (datum static and residual static corrections), and interpretation (the impact that unresolved static corrections, especially the long-wavelength or low-spatial-frequency component, have on interpretation of the final section). Simple explanations of the underlying principles are included in an attempt to remove some of the mystique of static corrections. The principles involved are illustrated with simple models, supplemented with many data examples. This book details differences in approaches that must be considered among 2D, 3D, and crooked-line recordings as well as between P-wave and S-wave surveys. Static corrections are shown to be a simplified yet practical approach to modeling the effects of the near surface where a more correct wavefield or raypath-modeled method might not be undertaken efficiently. Chapters cover near-surface topography and geology; computation of datum static corrections; uphole surveys; refraction surveys; static corrections limitations and effect on seismic data processes; residual static corrections; and interpretation aspects. An extensive index and a large list of references are included.”