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:
Nov. 24, 2015
Filed:
Mar. 17, 2014
Schlumberger Technology Corporation, Sugar land, TX (US);
Richard Bloemenkamp, Issy-les-Moulineaux, FR;
Schlumberger Technology Corporation, Houston, TX (US);
Abstract
Techniques related to making resistivity measurements of an underground formation surrounding a borehole involve using a tool having an insulating pad mounted on the conductive body of the tool. The pad has a current injector electrode and a current return electrode electrically isolated from each other and mounted on a face of the pad. The pad is positionable in use to be adjacent the wall of the borehole. At least two impedance ratios are determined. The first is the ratio of the electrical impedance between the current injector electrode and the tool body and the electrical impedance between the current return electrode and the tool body. The second is the ratio of the electrical impedance between the current injector electrode and the formation, and the electrical impedance between the current return electrode and the formation on the other hand. The tool is arranged such that in operation, the two impedance ratios are substantially equal and there is substantially no potential difference between the tool body and the formation.