Patent ID: 6969994

Claim:
A method for determining a parameter of a subsurface formation traversed by a borehole, comprising: a) disposing a logging instrument having a longitudinal axis and equipped with multiple antennas within the borehole, a first pair of transmitter-receiver antennas with a first antenna having its axis oriented in a first direction at angle Î¸ 1 with respect to the instrument axis and a second antenna having its axis oriented in a second direction at angle Î¸ 2 with respect to the instrument axis, a second pair of transmitter-receiver antennas with a first antenna, located near the second antenna of the first pair, having its axis oriented in said first direction at said angle Î¸ 1 with respect to the instrument axis and a second antenna, located near the first antenna of the first pair, having its axis oriented in said second direction at said angle Î¸ 2 with respect to the instrument axis, wherein said first and second directions are different; b) transmitting electromagnetic energy from the transmitter antenna of said first transmitter-receiver pair; c) measuring a signal associated with the transmitted energy at the receiver antenna of said first transmitter-receiver pair; d) transmitting electromagnetic energy from the transmitter antenna of said second transmitter-receiver pair; e) measuring a signal associated with the transmitted energy at the receiver antenna of said second transmitter-receiver pair; and f) calculating a difference between the measured signals of steps (c) and (e) to determine the formation parameter.