| 摘要 |
<p>SLM-20.1524 TO ALL WHOM IT MAY CONCERN: Be it known that I, JAMES H. MORAN, citizen of the United States, residing in the State of Texas, have invented an improvement in INDUCTION LOGGING APPARATUS AND METHOD of which the following is a SPECIFICATION An induction well logging apparatus and method is disclosed for determining dip and/or anisotropy parameters of formations surrounding a borehole. A transmitter is provided and includes a first transmitter coil having an axis which is substantially parallel to the borehole axis and a second transmitter coil having an axis which is substantially perpendicular to the borehole axis. A receiver is provided and includes first and second receiver coils having axes which are substantially mutually orthogonal. Each of the receiver coils is substantially perpendicular to the borehole axis. The transmitter and receiver are mounted in a mechanically passive manner on a support member adapted for movement through the borehole. The transmitter coils are energized in a manner which permits the separate detection at the receivers of the currents induced in the formations by each of the two transmitter coils. The reactive components of the detected signals are used to obtain dip and/or anisotropy parameters of the formations. The formation dip angle and/or dip azimuth angle can be determined without dependence on anisotropy. Anisotropy can also be obtained using the described configuration. All advantage of the disclosed technique is that dip angle and dip azimuth angle can be obtained from voltages induced (via the formations) as between coils which are orthogonal to each other. Accordingly, most of the usual problems associated with direct coupling are avoided.</p> |
