Communications – electrical: acoustic wave systems and devices – Seismic prospecting – Land-reflection type
Patent
1982-05-19
1990-06-05
Lobo, Ian J.
Communications, electrical: acoustic wave systems and devices
Seismic prospecting
Land-reflection type
367 25, 181102, 181104, 181106, G01V 140
Patent
active
049320033
ABSTRACT:
The quadrupole shear wave logging device of this invention includes a logging sonde, means for generating a quadrupole shear wave in the earth formation surrounding a borehole containing fluid, and means for detecting in the fluid the refraction of the quadrupole shear wave. In the preferred embodiment, the generating means comprises four similar sectors of a hollow piezoelectric cylinder. The four cylinders are polarized radially. The four sectors are so connected to the sonde that they are in the form of a split cylinder coaxial with the sonde axis. Electrical pulses of similar waveforms are applied across the inner and outer cylindrical surfaces of each sector to vibrate the four sectors. The electrical pulses are of such polarities that, during their initial motions of vibration, two oppositely situated sectors are caused to move outward and the remaining two oppositely situated sectors to move inward substantially simultaneously. Thus, the oppositely situated sectors will vibrate in phase whereas adjacent sectors will vibrate substantially opposite in phase. The vibrations of the four sectors generate four pressure waves: two positive pressure waves and two negative pressure waves. The four pressure waves generated will interfere and produce a quadrupole shear wave in the formation. The pressure wave in the fluid caused by refraction of such quadrupole shear wave is detected by the detecting means comprising two detectors in the fluid spaced apart longitudinally from each other and from the generating means. Shear velocity of the formation may be determined from the time interval between the detections of the refraction of the quadrupole shear wave by the two detectors.
REFERENCES:
patent: 2209100 (1940-07-01), Minton
patent: 3325780 (1967-06-01), Horan
patent: 3360664 (1967-12-01), Straube
patent: 3363118 (1968-01-01), Sims
patent: 3583677 (1971-06-01), Phillips
patent: 3593255 (1971-07-01), White
patent: 3821740 (1974-06-01), Ehrlich
patent: 3992693 (1976-11-01), Martin et al.
patent: 4237399 (1980-12-01), Sakamoto
patent: 4245172 (1981-01-01), Shirley
"Theoritical Basis of Quadrupole Well-logging," Gawin, A., Acta Geophysica Polonica, vol. 19, #2, 1971.
Graham A. Winbow, "How To Separate Compressional and Shear Arrivals in a Sonic Log" 50th Annual Int. Meeting of SEG, Houston, Texas, Nov. 17-20, (1980).
J. E. White, et al., "Computed Response of an Acoustic Logging Tool", Geophysics, vol. 33, No. 2 (Apr. 1968), pp. 302-310.
J. E. White, "The Hula Log: A Proposed Acoustic Tool," Trans Soc. Professional Well Log Analysts, Eighth Annual Logging Symposium, Paper I (1967).
Chen Sen-Tsuen
Rice James A.
Winbow Graham A.
Equitz Alfred A.
Exxon Production Research Company
Lobo Ian J.
O'Niell Herbert E.
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