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. 28, 2005
Filed:
Dec. 12, 2002
Anthony L. Collins, Houston, TX (US);
Andrew Hawthorn, Stafford, TX (US);
Cengiz Esmersoy, Sugar Land, TX (US);
Anthony L. Collins, Houston, TX (US);
Andrew Hawthorn, Stafford, TX (US);
Cengiz Esmersoy, Sugar Land, TX (US);
Schlumberger Technology Corporation, Sugar Land, TX (US);
Abstract
Techniques are presented for determining the drift of a clock adapted for subsurface disposal. Seismic signals are transmitted through the subsurface medium from an uphole location at selected times, acoustic signals associated with the transmitted seismic signals are received with acoustic sensors at identified downhole locations. First and second transit times for acoustic signals received at an identified downhole reference location are determined using the clock. A time difference between the first and second signal transit times at the reference point is calculated to determine the clock drift.