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:
Jan. 27, 2004
Filed:
Jan. 03, 2002
Tawassul Ali Khan, Cypress, TX (US);
Sofia Khan McGuire, Houston, TX (US);
Other;
Abstract
A method for determining the location and the orientation of the open natural fractures in an earth formation from the interaction of the two seismic signals, one signal transmitted into the formation from one wellbore and the second signal transmitted from the surface of the earth, the interaction of the two seismic signals as they simultaneously propagate through the fractured space is recorded in the second wellbore. The seismic signal transmitted from the surface is a lower frequency acoustic pulse of large amplitude identified as 'modulation' wave and the signal transmitted from the wellbore is a higher discrete frequency seismic signal, identified as 'carrier' wave. The interaction of the ‘carrier’ wave during the compression and rarefaction cycles of the ‘modulation’ signal is recorded. By subtracting the ‘carrier’ from the interaction signal, the ‘modulation-pulse’, which represents the arrival time of the surface generated acoustic pulse, from the surface source to the subsurface fractures is extracted. By plotting the arrival times and the relative amplitudes of the ‘modulation-pulse’, the orientation and the location of the open fractures is determined.