Halliburton Energy Services, Inc.

Arthur Cheng

Chung Lung Chang

Gary Wayne Kainer

Mark Vincent Collins

Burkay Donderici

Michael Thomas Pelletier

Li Gao

Glenn Andrew Wilson

Batakrishna Mandal

Abbas Arian

Paul Andrew Cooper

Chen Li

Randall Bennett Jones

Thurairajasingam Rajasingam

Wei Zhang

Ruijia Wang

Jing Jin

Clovis Satyro Bonavides

Yinghui Lu

Wei Li

Paul G Junghans

Jennifer Anne Market

Philip William Tracadas

Zhijuan Zhang

Tatiana Gilstrap

Nigel Clegg

Steve Zannoni

Donghong Pei

Pradip Kumar Mukhopadhyay

Janusz Peron

Rob Epstein

Hong Li Hou

Mandal Batakrishna

Deconvolution-based processing of ultrasonic waveforms enables robust calculation of two-way travel time for an ultrasonic caliper, particularly in the presence of multiple, proximal reflectors (e.g., mud cake, formation, casing, cement, etc.).

Ultrasonic waveform processing using deconvolution in downhole environments

An apparatus and a method for measuring a speed of sound in a fluid in a well bore may include a frame adapted to receive the fluid there through are provided. The apparatus includes an acoustic source mounted on the frame; an acoustic detector to measure a signal propagating through the fluid, the acoustic detector disposed proximate the frame at a known distance from the acoustic source; and a test circuit adapted to synchronize the acoustic detector with a signal propagating through the frame. A method to determine physical properties of a fluid in a geological formation including a shear wave anisotropy in the geological formation and the formation composition using the fluid density and the fluid speed of sound is also provided.

Method and apparatus for the downhole in-situ determination of the speed of sound in a formation fluid

A method of obtaining an equivalent tool model includes obtaining a set of known well data, in which the known well data includes sensor data measured by a logging tool and an actual dispersion response, and the logging tool has an actual tool size. The method also includes obtaining one or more well parameters from the known well data, and inputting the one or more well parameters and a model tool size into a rigid tool model. The method further includes obtaining an estimated dispersion response from the rigid tool model, and fitting the estimated dispersion response to the actual dispersion response by adjusting the model tool size.

Method of minimizing tool response for downhole logging operations

Various embodiments include apparatus and methods to estimate formation mobility from Stoneley waveforms. An objective function can be generated that represents misfit between measured Stoneley pressure values and synthetic pressure values. A minimization process can be applied to the objective function to estimate formation mobility and intrinsic attenuation. Additional apparatus, systems, and methods are disclosed.

Estimate of formation mobility from Stoneley waveforms

The disclosure addresses multiple embodiments of an acoustic isolator, and an acoustic logging tool which incorporates the acoustic isolator. The acoustic isolator is configured to minimize acoustic transmissions which could otherwise adversely affect acoustical measurements being made by an acoustic receiver. The described acoustic isolators include a plurality of longitudinally arranged mass members coupled to a central supporting structure, in a configuration to reduce acoustic transmissions in at least selected frequency ranges.

Acoustic isolator for downhole tools

Apparatus and techniques are described, such as for obtaining information indicative of an acoustic characteristic of a formation, including using a transducer assembly, comprising a base plate, a first piezoelectric slab and a second piezoelectric slab. The base plate includes a first region extending axially in a first direction beyond the first and second piezoelectric slabs along a specified axis of the base plate and a second region extending axially in a second direction, opposite the first direction, beyond the first and second piezoelectric slabs. In various examples, a length of the first region along the specified axis is different than a length of the second region to provide an asymmetric configuration. In various examples, an anchoring element is mechanically coupled to the base plate at a location corresponding to a node location of a specified acoustic vibration mode.

Asymmetric bender bar transducer

In some embodiments, an apparatus and a system, as well as a method and an article, may operate to determine a compressional velocity (CV) of a geological formation, to determine a reflection coefficient (RC) associated with the geological formation, and to determine a density of the geological formation based on the CV and the RC. The CV and RC may be determined from values associated with sonic and ultrasonic velocity measurements. Additional apparatus, systems, and methods are described.

Sourceless density determination apparatus, methods, and systems

Various embodiments include apparatus and methods to process acoustic signals according to joint time-frequency processing. The joint time-frequency processing can combine features of both time-based processing and frequency-based processing. This processing may be based on delay calculation from amplitude phases generated from the acoustic signals. The joint time-frequency processing may be applied to a variety of applications to evaluate properties associated with a borehole or surrounding formations. Additional apparatus, systems, and methods are disclosed.

Joint time-frequency processing for borehole acoustic arrays

Various systems and methods for implementing and using a variable stiffness downhole tool housing include cylindrical segments positioned along a common axis, with a pair of segments each coupled to a bulkhead and positioned at either axial end of the tool housing. The housing also includes a flexible cylindrical sleeve, positioned along the common axis between two of the plurality of cylindrical segments, that includes a first and second region with an outer diameter no larger than a common segment inner diameter and a third region located between the first and second regions and with an outer diameter no larger than a common segment outer diameter (the first and second regions each at least partially inserted into an end of one segment). A stiffness controller controls the stiffness of the tool housing by controlling at least part of an axial force exerted between the two segments.

Variable stiffness downhole tool housing

Acoustic logging systems and methods are provided with multi-mode inversion for at least vertical shear slowness and shear anisotropy. At least some method embodiments acquire waveforms for multiple acoustic wave modes as a function of tool position in a borehole, derive position-dependent mode dispersion curves from the waveforms, match the derived dispersion curves with parameterized dispersion curves to determine a vertical shear slowness and a shear anisotropy as a function of position, and displaying a borehole log that represents at least one of the vertical shear slowness and the shear anisotropy as a function of position. The objective function employed for the inversion is evaluated across multiple wave propagation modes and mud slownesses and may employ an adaptive, frequency-dependent weighting based on distance between the derived dispersion curves and the parameterized dispersion curves.

Acoustic logging systems and methods employing multi-mode inversion for anisotropy and shear slowness

In some embodiments, apparatus and systems, as well as methods, may operate to shift signal data associated with a set of receivers, in time or phase with respect to signal data associated with a receiver reference point, to transform the signal data into shifted data, wherein the signal data corresponds to energy waves propagated through a geological formation before being received by the set of receivers; to multiply the shifted data by a complex conjugate of the signal data associated with the receiver reference point to provide differential phase values; to sum and average the differential phase values to provide differential phase semblance values; and to publish the differential phase semblance values, or information derived from the differential phase semblance values to one of a storage medium, a hardcopy printout, or a display. Additional apparatus, systems, and methods are disclosed.

Differential phase semblance apparatus, systems, and methods

In some embodiments, apparatus and systems, as well as methods, may operate to record a plurality of acoustic waveforms comprising cross-dipole waveforms and corresponding to acoustic waves received 5 at azimuthally orthogonal dipole receiver arrays surrounded by a geological formation, the waves being generated by azimuthally orthogonal dipole transmitter arrays. Further activity may include defining an objective function dependent on the cross-dipole waveforms, eigenvalues, an azimuth angle corresponding to an 10 orientation of the transmitter and receiver arrays; minimizing the objective function with respect to said angle and the set of auxiliary parameters; and determining at least one property of the geological formation based on the global minimum. Additional apparatus, systems, and methods are disclosed.

Formation property determination apparatus, methods, and systems

In some embodiments, an apparatus and a system, as well as a method and an article, may operate to receive seismic survey data for use with an isotropic velocity model describing a selected geological formation volume. Further activity may include exhaustively searching the seismic survey data to provide an error map, globally optimizing the error map to provide anisotropy parameters for the selected geological formation volume, and inverting the anisotropy parameters to transform the isotropic velocity model into an anisotropic velocity model for the selected geological formation volume. Additional apparatus, systems, and methods are described.

Data double-searching apparatus, methods, and systems

In some embodiments, apparatus and systems, as well as methods, may operate to record a plurality of acoustic waveforms corresponding to acoustic waves received at azimuthally orthogonal dipole receiver arrays surrounded by a geological formation, the waves being generated by azimuthally orthogonal transmitter arrays. Further activity may include analytically estimating a global minimum of a predefined objective function with respect to an azimuth angle at a point in an auxiliary parameter space associated with a set of auxiliary parameters, minimizing the objective function at the analytically estimated angle with respect to the auxiliary parameters, removing existing ambiguities associated with the fast and slow principal flexural wave axes, and determining at least one property of the geological formation based on the global minimum. Additional apparatus, systems, and methods are disclosed.

Growing community of inventors

Houston, TX, United States of America

Arthur Cheng