Halliburton Energy Services, Inc.

Qingtao Sun

Chung Lung Chang

Ruijia Wang

Richard Timothy Coates

Xiang Wu

Yao Ge

Mark Vincent Collins

Randolph Scott Coles

Amit Padhi

Jiajun Zhao

Brenno Caetano Troca Cabella

Pablo Vieira Rego

Marco Aurelio Luzio

Andrew Clair Colbert

Federico Lucas, Jr

João Vicente Gonçalves Rocha

Systems and methods of evaluating well cementation are disclosed. In certain embodiments, a tool is lowered into a casing surrounded by an annular material within a wellbore. An emitter of the tool emits an acoustic signal at a first pitch angle selected to excite a mixed-mode Lamb wave comprising a symmetric extensional (Sn) mode and an asymmetric flexural (An) mode of a Lamb wave in the casing. A receiver of the tool that is disposed at a first distance from the emitter receives a portion of the Lamb wave that has leaked from the casing at approximately the first distance.

Cement evaluation

An acoustic logging tool may comprise a center load carrying pipe, a receiver module connected to the center load carrying pipe, one or more transmitter modules connected to the center load carrying pipe, and one or more mass modules connected to the center load carrying pipe.

Sonic through tubing cement evaluation

Methods, systems, and program products are disclosed for implementing acoustic logging and determining wellbore material characteristics. In some embodiments, a method may include determining a polar differential signal for each of one or more pairs of azimuthally offset acoustic measurements within a wellbore. A reference azimuth is identified based, at least in part, on comparing the polar differential signals to a modeled bonding differential signal within a target response window. The method further includes determining differences between an acoustic measurement at the reference azimuth and acoustic measurements at one or more other azimuths and determining a wellbore material condition based, at least in part, on the determined differences.

Through tubing acoustic measurements

A method comprises positioning a receiver in a borehole and determining an offset acoustic waveform at a target point. The method includes generating a reverse time sequence waveform of the determined offset acoustic waveform and generating, by a transmitter, an acoustic pulse based on the reverse time sequence waveform. The method includes detecting, by the receiver, an acoustic response to the acoustic pulse.

Downhole acoustic measurement

To generate dispersion curves for acoustic waves in a radially layered system, a matrix M containing solutions to the wave equation subject to the boundary conditions of the system is constructed. The reciprocal condition number (RCN) of the matrix M is determined as a function of acoustic wave frequency and slowness. The local minima of the RCN in the frequency-slowness plane produces the dispersion curves corresponding to allowable acoustic modes in the system. A sensitivity analysis which identifies the dispersion curves dependent on a selected parameter. The dispersion curves independent of the perturbed parameters are eliminated by perturbing the modeling parameters and generating the RCN of the perturbed matrix M and then subtracting the RCN values of the unperturbed matrix M, leaving the dispersion curves that exhibit dependence on the selected parameter.

Acoustic dispersion curve identification based on reciprocal condition number

A logging-while-drilling (LWD) tool for use within a formation. The LWD tool may include a transmitter, a receiver, and an acoustic isolator. The transmitter may be operable to transmit an acoustic signal into the formation. The receiver may be operable to receive an acoustic response from the formation. The acoustic isolator may be positioned longitudinally between the transmitter and the receiver to reduce a transfer of acoustic energy between the transmitter and the receiver through the LWD tool. The acoustic isolator may include annular chambers formed in a body of the acoustic isolator and positioned along a longitudinal axis of the acoustic isolator.

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Spring, TX, United States of America

Qingtao Sun