The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 29, 1993
Filed:
Sep. 04, 1991
William B Vail, III, Bothell, WA (US);
Para Magnetic Logging, Inc., Woodinville, WA (US);
Abstract
Methods of operation of an apparatus having at least two pairs of voltage measurement electrodes vertically disposed in a cased well to measure the resistivity of adjacent geological formations from inside the cased well. During stationary measurements with the apparatus at a fixed vertical depth within the cased well, the invention herein discloses methods of operation which include a measurement step and subsequent first and second compensation steps respectively resulting in improved accuracy of measurement. First and second order errors of measurement are identified, and the measurement step and two compensation steps provide methods to substantially eliminate their influence on the results. A multiple frequency apparatus adapted to movement within the well is described which simultaneously provide the measurement and two compensation steps.