E - Fixed Constructions – 21 – B
Patent
E - Fixed Constructions
21
B
E21B 47/14 (2006.01) E21B 47/12 (2006.01) G01V 1/42 (2006.01)
Patent
CA 2081648
-16- ABSTRACT OF THE DISCLOSURE A drill bit drilling a borehole is used as a strong high frequency, subsurface seismic source in combination with at least one receiver in a preexisting borehole to determine the continuity of a subsurface formation layer extending between the borehole being drilled by the drill bit and the borehole in which the receiver is located. The receiver(s) in the preexisting borehole may be any conventional seismic receiver or receivers, such as hydrophones or geophones. The receiver or receivers are positioned in the preexisting borehole at a depth adjacent the formation layer whose continuity is to be determined. The depth (position), velocity and thickness of the layer is determined from a conventional well log of the preexisting borehole. A frequency power spectrum for a preselected frequency range (the range is selected based on the logging data) may be computed from the signals recorded by the receiver(s). Several such spectra may be computed from signals recorded for several different time intervals and then summed to increase the signal-to-noise ratio. A large amplitude in this power spectrum (or the detected signals) is indicative of a low velocity layer that is continuous between the drill bit source and the borehole containing the receivers.
Borden Ladner Gervais Llp
Exxon Production Research Company
LandOfFree
Method for continuity logging does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method for continuity logging, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for continuity logging will most certainly appreciate the feedback.
Profile ID: LFCA-PAI-O-1543880