04583046 is referenced by 231 patents and cites 7 patents.

An induced polarization tool using focused electrodes that uses direct coupling in the focusing loop to prevent spurious phase shifts. The invention uses a differential-in differential-out amplifier and voltage-controlled resistances to provide zero potential difference between pairs of monitoring electrodes. The measured current and voltage are digitized downhole and transmitted to the surface. At the surface means are provided for determining in-phase and quadrature response.

Title
Apparatus for focused electrode induced polarization logging
Application Number
6/505623
Publication Number
4583046
Application Date
June 20, 1983
Publication Date
April 15, 1986
Inventor
Monroe H Waxman
Houston
TX, US
Harold J Vinegar
Houston
TX, US
Assignee
Shell Oil Company
TX, US
IPC
G01V 3/24
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