Abstract: A method of determining properties of a bonding material disposed outside of a casing in a borehole includes at least two of the following three pairs of operations: (1) inducing an acoustic wave in the casing, and measuring attenuation of the acoustic wave, by pulse-echo or other cement bond logging measurement; (2) inducing an SH wave in the casing, and measuring attenuation of the SH wave; and (3) inducing a Lamb wave in the casing, and measuring attenuation of the Lamb wave. (2) and/or (3) may be performed by an electromagnetic acoustic transducer. The method further includes determining the shear velocity or shear impedance and the compressional velocity or compressional impedance of the bonding material based on appropriate ones of the measurements. The bonding material may be cement.

Abstract: A method of determining properties of a bonding material disposed outside of a casing in a borehole includes at least two of the following three pairs of operations: (1) inducing an acoustic wave in the casing, and measuring attenuation of the acoustic wave, by pulse-echo or other cement bond logging measurement; (2) inducing an SH wave in the casing, and measuring attenuation of the SH wave; and (3) inducing a Lamb wave in the casing, and measuring attenuation of the Lamb wave. (2) and/or (3) may be performed by an electromagnetic acoustic transducer. The method further includes determining the shear velocity or shear impedance and the compressional velocity or compressional impedance of the bonding material based on appropriate ones of the measurements. The bonding material may be cement.

Abstract: A method and apparatus for evaluating a bond between a formation and a bonding material. The method includes emitting a shear wave into the tubular, recording the response of the shear wave, and evaluating the response to obtain bond information. The bond information includes bond material thickness and efficacy of the bond between cement and formation. The method includes studying and utilizing the time lag of the direct wave and wave events, as well as the interference of these waves on a spectral graph. A calibration method is included as well.

Abstract: A method and apparatus for evaluating a bond between a formation and a bonding material. The method includes emitting a shear wave into the tubular, recording the response of the shear wave, and evaluating the response to obtain bond information. The bond information includes bond material thickness and efficacy of the bond between cement and formation. The method includes studying and utilizing the time lag of the direct wave and wave events, as well as the interference of these waves on a spectral graph. A calibration method is included as well.