f Optimal array focusing deconvolution for VSP

We describe a technique for performing deconvolution of VSP data. The method is a two-step process that involves (1) estimating the source signature, and (2) applying a least squares optimum deconvolution operator that minimizes the noise not coherent with the source signature estimate. The optimization is done in the frequency domain, which introduces the frequency domain semblance as an extra factor in the deconvolution operator. Comparison to conventional processing of the data shows that the introduction of the semblance weights can give significantly improved results.