摘要 |
The present invention relates to a method of seismic exploration utilizing vibrationally generated, elliptically polarized shear waves (62) in an earth medium (38) for subsequent detection of one or more dimensions of orthogonal particle motion. A preferred form of shear wave source (40) is of a type which couples a continually rotating longitudinal force into an earth medium thereby to propagate an elliptically polarized shear wave (62) for refraction, reflection or subsurface detection, for various forms of exploration. |