Patent Document ID: 9057797
Application ID: 13874275
Patent Flag: 1

Claim One:
1. A system comprising: an electromagnetic logging tool having transmitter and receiver antennas oriented as a longitudinal magnetic dipole and at least one of a tilted magnetic dipole or a transverse magnetic dipole, wherein the electromagnetic logging tool is capable of making dipole sensitive electromagnetic measurements within a surface formation; and a processor capable of: (a) determining formation layer boundaries and horizontal resistivities of the formation layers based upon longitudinal magnetic dipole measurements obtained using the electromagnetic logging tool; (b) determining vertical resistivities of the formation layers based upon anisotropy sensitive electromagnetic measurements obtained using the electromagnetic logging tool; (c) inverting the symmetrized and anti-symmetrized electromagnetic measurements obtained using the electromagnetic logging tool to update the vertical resistivities of the formation layers obtained at (b) to obtain improved vertical resistivities of the formation layers and to determine corresponding dips thereof; (d) inverting the longitudinal magnetic dipole measurements, the anisotropy sensitive measurements, and the symmetrized and anti-symmetrized measurements to update the improved vertical resistivities obtained at (c) to obtain further improved vertical resistivities, update the layer boundaries obtained at (a) to obtain improved layer boundaries, and update the dips obtained at (c) to obtain improved dips; and (e) inverting the longitudinal magnetic dipole measurements, the anisotropy sensitive measurements, and the symmetrized and anti-symmetrized measurements to update the horizontal resistivities obtained at (a) to obtain improved horizontal resistivities, update the improved layer boundaries obtained at (d) to obtain further improved layer boundaries, and update the improved dips obtained at (d) to obtain further improved dips.