Method and tool for directional electromagnetic well logging

摘要

A directional antenna, system and method are provided. The methods include acquiring a plurality of data pairs, each data pair comprising an induced signal at a receiver and a corresponding toolface angle using a tool including at least one antenna assembly, as described herein. It further discloses a method to generate a measurement containing information about the directionality of the formation by calculating areas of an induced signal function approximated by the plurality of data pairs.

主权项

1. A method, comprising:
disposing (770) a tool (120) in a borehole (11) disposed in a formation comprising:
at least one transmitter (21) and at least one receiver (23);wherein at least one of the transmitter (21) and the receiver (23) is a directional antenna; andwherein the transmitter (21) and the receiver (23) are axially spaced relative to one another; acquiring (774) in the borehole (11) a plurality of data pairs, each data pair comprising an induced signal at the at least one receiver (23) and a corresponding toolface angle from among a total toolface range; calculating (776) at least one area of an induced signal function approximated by the plurality of data pairs; and generating a measurement characterizing the formation using the calculated at least one area.