The comparison of seismic data recorded at very different frequencies (a few hundred Hz for VSP and a few ten KHz for acoustic logging) and of dipmeter information can help for the interpretation of seismic anomalies. The VSP can have a lateral investigation of several ten or even hundred meters and a 1 to 10 meters vertical resolution. The acoustic logging used in reflected or diffracted modes has a vertical resolution of a few ten centimeters an 1 to 20 meters lateral investigation.