Kambiz A. Safinya

Effect of dipping beds on the response of induction tools

This paper describes a model for studying the effect of dipping beds on the response of induction tools. In this study, the authors neglect the effects of the borehole and the invaded zone to make the problem solvable in a closed form. The magnetic fields of an equivalent magnetic dipole, whose axis is arbitrarily oriented with respect to the direction of stratification, are obtained everywhere in an arbitrarily number of beds whose conductivities can be arbitrarily assigned. Induction tool response can be easily obtained with the aid of these magnetic field calculations. In addition to describing the model, the authors also study the effect of dip angle on the apparent resistivity and the apparent bed thickness as read by induction tools in several typical logging configurations.

The response of the electromagnetic propagation tool to bed boundaries

Utilisation of computer models corroborated by laboratory experimental data to show that the EPT can resolve beds <2 in. thick. The agreement of the experimental and theorical results demonstrates the ability of the dipole model to predict the response of the EPT antennas.