The microinduction sensor consists of miniature transmitter and receiver coils. It can be used to make a noncontacting conductivity measurement of inhomogeneous media. Due to the small size of the sensor, it is capable of centimeter resolution, and is therefore useful in dipmeter logging of boreholes filled with nonconductive fluid. The theory of the microinduction sensor is described. A Green's Function approach is used to formulate an integral equation, whose lowest Born approximation and geometrical factor theory can be used to gain physical intuition and to predict the response of the sensor in certain special cases. To solve more general problems, a full wave theory for the sensor over a layered medium is introduced that includes all electrodynamic effects. Using the full wave theory, the effect of sensor tilt is ascertained. In order to solve the problem of general inhomogeneous media in a computationally efficient manner, the integral equation can be solved with a variational principle calculation that incorporates the Maxwell-Wagner charge effect.
|Original language||English (US)|
|Number of pages||13|
|Journal||IEEE Transactions on Geoscience and Remote Sensing|
|State||Published - Nov 1988|
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Earth and Planetary Sciences(all)