Joint inversion of well-log data

We consider the processing of well log data, in which the measurements taken at a reservoir level (fluid filled porous rock) give the properties of the compound medium. From a collection of noisy well log measurements, it is desired to estimate the parameters characterizing the formation, namely the porosity and the volume ratio of the individual fluid specimens (water, oil and water). The problem is solved by inverting the constitutive equations. We show that ambiguities are reduced by using jointly seismic, electrical and density dat