Analysis of Directional Logging Tools in Anisotropic and Multieccentric Cylindrically-Layered Earth Formations

We develop a pseudoanalytical method for the analysis of directional resistivity well-logging tools consisting of multiple tilted-coil antennas in cylindrically-layered Earth formations which have anisotropic conductivities and where each layer may be eccentric to the others (multieccentric formations). The cylindrically-layered, anisotropic, and multieccentric scenarios considered here are often encountered in deviated/horizontal drilling for hydrocarbon exploration, where the logging tool may be eccentric to the borehole due to mechanical vibrations and/or gravitational pull, and where eccentric invaded zones (of mud filtrate into the formation) may also arise because of gravitational pull on the mud filtrate.