Essai de determination automatique des vitesses sismiques par mesures entre puits
P. Bois, M. Porte, M. Lavergne and G. Thomas
Journal name: Geophysical Prospecting
Issue: Vol 19, No 1, March 1971 pp. 42 - 83
Info: Article, PDF ( 1.95Mb )
Large memory computers create new possibilities for seismic interpretation in well-drilled areas, and more generally in problems involving deep sources.
Records obtained by well-to-surface, surface-to-well and/or well-to-well propagation contain a large amount of information, owing to the great number of seismic rays travelling throughout the subsurface.
This paper considers two successive steps:
— direct case: computation of the first arrival times of seismic rays propagating through a two-dimensional subsurface with given vertical and horizontal velocity variations;
— inverse case: computation of a two-dimensional velocity distribution, knowing the travel times of seismic rays through the subsurface.
A computer program has been elaborated to solve both direct and inverse problems. There are no difficulties with the direct case; a certain number of uncertainties remain with the inverse case.