Patent ID: 8085050

Claim:
A logging tool having a tool axis, the tool comprising: a first transmitter antenna to transmit an electromagnetic wave having a first frequency into a formation; a second transmitter antenna to transmit an electromagnetic wave having a second frequency into the formation; at least one receiver antenna to receive an electromagnetic wave from the formation, wherein at least one of the transmitter and receiver antennas is tilted with respect to the tool axis; a rotational angle sensor to determine an azimuthal angle of the logging tool; a processor coupled to the at least one receiver antenna and the rotational angle sensor to collect at least one formation measurement for at least three azimuthal angles at each of the first and second frequencies, and to determine based on said measurements at least one sinusoidal parameter characterizing the azimuthal variation of said at least one formation measurement at the first frequency and at least one additional sinusoidal parameter characterizing the azimuthal variation of said at least one formation measurement at the second frequency.