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:
May. 22, 2007
Filed:
May. 12, 2004
Simon James, Clamart Cedex, FR;
Peter Fitzgerald, Clamart Cedex, FR;
Simon James, Clamart Cedex, FR;
Peter Fitzgerald, Clamart Cedex, FR;
Schlumberger Technology Corporation, Sugar Land, TX (US);
Abstract
An acoustic detection of a discrete acoustic signal allows to detect a leak behind a casing () of a borehole. An acoustic amplitude (AA) is sampled during a recording time period () at a determined position along the tube. Time intervals () are defined inside of the recording time period (), and for each time interval () the measured acoustic amplitudes are processed to obtain respectively a corresponding power-frequency spectrum (). A plurality of the power-frequency spectra are analyzed to identify the discrete acoustic signal by detecting time and frequency dependant changes of power. Preferably the processing involves a Fourier transform analysis. A power-frequency time plot is used to conveniently identify the discrete acoustic event.