Induction logging utilizing resistive and reactive induced signal components to determine conductivity and coefficient of anisotropy
US4302722A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 15, 1979 |
| Grant date | Nov 24, 1981 |
| Priority date | — |
| Expiry date | Jun 15, 1999 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01V3/28
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention is directed to induction logging apparatus and method for obtaining measurements dependent upon the vertical conductivity component of formations surrounding a borehole. The disclosed techniques can also be used to determine horizontal as well as vertical conductivity of the formations, and thereby achieve determination of formation anisotropy. A transmitter coil is provided with its axis substantially perpendicular to the borehole axis. A receiver coil is provided in spaced relation to the transmitter coil. The axis of the receiver coil is also substantially perpendicular to the borehole axis, and is preferably parallel to the axis of the transmitter coil. Means are provided for detecting signals induced in the receiver coil, these signals being a measure of the formation vertical conductivity. In a preferred embodiment of the invention, the detecting means is operative to detect both the resistive and reactive components of the signals induced in the receiver coils. Indications of formation vertical conductivity are obtained by combining the detected resistive and reactive components. In a further form of the invention, the formation horizontal conductivity can also…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.