Fast Frechet derivative calculation using an auxiliary source array method; An application to array resistivity measurements

摘要

Frechet derivatives provide the vital information for parameteric resistivity inversion, but the calculation for a multidimensional problem is often computer intensive. This paper presents a new technique for fast calcula- Tion of the Frechet derivatives of resistivity measure- Ments with respect to formation resistivity properties. The technique, referred to as the auxiliary source array Method (ASAM), generalizes the reciprocity principle- Based methods in that for closely spaced receivers it may Not be necessary to place a fictitious source at each re- Ceiver location.