Inversion of Travel Time for Velocity Using Multi-Spacing Sonic Tools

Abstract

Spatial resolution of sonic logs is greatly affected by the minimum spacing between receivers. Improvements can be made, however, when the spatial sampling of the formation is less than the minimum spacing. This paper proposes a recursive least squares inversion of travel times based on the Kalman filter. This formulation emphasizes the noise.content of the data as a factor limiting resolution. Synthetic data as well as real data processing is presented here.