61 results about "Stoneley wave" patented technology

Stoneley-wave data acquired in the LWD environment are used to characterize/estimate formation permeability. Real-time Stoneley-wave time-delay/slowness and center-frequency/attenuation data are used to indicate/characterize formation permeability even during drilling. The use of stabilizers mounted at the tool ends helps maintain the tool position from severe decentralization, reducing ambiguities in the permeability characterization/estimation. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

A method and apparatus for assessing the permeability of a subterranean formation and the hydrocarbon and/or water content of the formation. The method includes emitting an acoustic signal, such as a Stoneley wave into the formation and sending an electro-magnetic pulse into the formation. An analysis of the response of the Stoneley wave in conjunction with an analysis of a measurement of the electrical potential within the wellbore provides information pertinent to permeability and fluid composition.

A dielectric substance is laminated on one surface of a piezoelectric substance, and an IDT and reflectors are disposed as electrodes at a boundary between the piezoelectric substance and the dielectric substance, and the thickness of the electrodes is determined so that the acoustic velocity of the Stoneley wave is decreased less than that of a slow transverse wave propagating through the dielectric substance and that of a slow transverse wave propagating through the piezoelectric substance, thereby forming a boundary acoustic wave device.

Cased-hole radial profiling of shear parameters from sonic measurements is disclosed. Example methods disclosed herein include determining a variation of a first shear modulus at a first radial position from a cased borehole in a formation based on a first weighted average of fractional variations of Stoneley wave velocities for different wavenumbers, the first weighted average based on first weights determined using a perturbation model including parameters to model the borehole casing, and determining variations of second and third shear moduli at respective second and third radial positions from the borehole based on second and third weighted averages of fractional variations of respective first and second flexural wave velocities for different wavenumbers, the first and second flexural wave velocities associated with respective first and second orthogonal borehole axial planes of the formation, the second and third weighted averages based on respective second and third weights determined using the perturbation model.

An acoustic source on a logging tool is used to generate acoustic waves in a borehole. Acoustic detectors on the logging tool measure the generated acoustic waves. Electrodes on the logging tool are used to measure the potential resulting from the generated acoustic wave. The output of the hydrophones and the electrodes corresponding to Stoneley wave components of the acoustic wave are processed to provide an estimate of formation permeability, acoustoelectric constant, and a velocity of a propagating second compressional wave in the formation.

The embodiment of the invention relates to a drilling following type acoustic logging device. The device comprises a drill collar, a transmission energy converter and a receiving energy converter, wherein the transmission energy converter and the receiving energy converter are arranged on the drill collar; the transmission energy converter comprises a first radiation metal block, a first mass metal block and a plurality of transmission type piezoelectric ceramic sheets; the receiving energy converter comprises a second radiation metal block, a second mass metal block and a plurality of receiving type piezoelectric ceramic sheets. According to the device, a multi-pole-source working mode combining a single pole, a dipole and quadrupole is utilized to directly measure stratum longitudinal wave, transverse wav, stoneley wave sound velocity, attenuation and other parameters which can provide reference and verification for each other or individually processed, so that the reliability and applicable scope of the device can be greatly improved and expanded.

The embodiment of the invention provides a method and device for determining horizontal crack widths. The method includes the steps that a numerical model of a to-be-treated well is built, and acoustic logging waveforms of the numerical model under all horizontal cracks are simulated; according to the acoustic logging waveforms under all horizontal cracks, the first stoneley wave amplitude variation amounts of the horizontal cracks are determined; according to the first stoneley wave amplitude variation amounts of all horizontal cracks, a relationship curve between the crack widths and the stoneley wave amplitude variation amounts is determined; according to the acoustic logging waveforms of the to-be-treated well, second stoneley wave amplitude variation amounts of all horizontal cracks in the to-be-treated well are determined; according to the relationship curve and the second stoneley wave amplitude variation amounts of all horizontal cracks in the to-be-treated well, the width of each horizontal crack in the to-be-treated well is determined. By means of the embodiment, the calculation accuracy of the horizontal crack widths can be improved.

The invention discloses a processing and interpreting method for array acoustic imaging logging data. The method comprises the following steps: S1, collecting and sorting multipole array acoustic logging data of a target well in a working area; S2, extracting the time difference of longitudinal waves, transverse waves and stoneley waves from the logging data with a time domain or a frequency domain method to obtain a time difference curve, and performing quality monitoring on the time difference curve; S3, constructing a transverse wave time difference curve of a dipole-free acoustic data well; S4, analyzing the fast and slow transverse wave anisotropy of acoustic imaging logging and applying analysis results. The method is simple, has low calculation workload and high calculation efficiency, can be applied to various geological target wells, and has high result precision.

The invention relates to a combined logging mode of a multipole logging-while-drilling device. The combined logging mode which comprises a drilling logging mode and a lifting logging mode is providedaccording to the actual needs of well drilling operation, full wave train measuring and orientation imaging of stratum longitudinal waves, transverse waves, Stoneley waves and the like can be achievedat the same time, and rich stratum evaluation information can be provided. Aiming at the fact that the working diameters of the different modes of the combined logging mode are different and transmitting and receiving need to be controlled synchronously, the invention further provides a signal transceiving synchronization method combining transceiving communication and synchronous control, the fact that the multipole logging-while-drilling device works according to set flow under each working mode and during the switching of different modes is guaranteed, and measuring efficiency is increased.

Production capability of cased hole perforations in a cased completed well lined with a casing in an under-pressured gas producing reservoir is tested. A sonde of a dipole shear or array sonic (full waveform) acoustic well logging tool is moved in a well bore of the cased completed well in the reservoir across a depth interval of interest, which covers cased hole perforations zones in the reservoir. The well logging sonde has in it an acoustic energy source and acoustic energy receivers. Responses are logged at depth intervals of interest to the transit of Stoneley waves along the casing walls from the acoustic energy source to the acoustic energy receivers. Measures of characteristics (e.g., travel time and attenuation) of the Stoneley wave are obtained. The responses are then processed to indicate production capability of the cased hole perforations.

The invention discloses a multi-layer board damage detection method based on a Stoneley wave energy transfer characteristic. According to the method, on the basis that in a multi-layer composite board, energy transfer exists on joints of two interfaces of Stoneley waves, under the condition of different excitation frequencies, distributions of energy magnitudes of the joints of interfaces between plates are different, and when a suitable excitation frequency is selected, independent detection of damage on a specific interface of the multi-layer composite board or simultaneous detection of damage on two interfaces of the multi-layer composite board can be achieved. The detection method is suitable for multi-layer composite board interface damage detection such as damage detection of a three-layer board, it can be guaranteed that fault information of all interfaces is detailed and accurate, the detection capacity is greatly improved, and implementation is convenient, easy and reliable.

A Stoneley wave is generated in a borehole in a saturated porous earth formation. Measurements are made of the velocity of motion of the formation and the fluid in the formation. The difference in the velocities is indicative of formation permeability. An additional measurement of the electric field at the borehole wall enables determination of the electroacoustic constant.

The invention discloses a method of evaluating anisotropism of a stratum by acoustic logging while drilling. The method comprises the following steps: acquiring full acoustic wave array data in a depth interval and processing the data to obtain frequency dispersion data of stoneley waves while drilling and quadrupole waves and respective power spectra; separately calculating theoretical frequencydispersion curves of stoneley waves and quadrupole waves by means of an assumed anisotropic value of the stratum and a slowness value of transverse waves; in respective processing frequency bands, calculating the error sum of squares of the theoretical frequency dispersion curves relative to the actually measured frequency dispersion data by weighting the power spectra and weighting the result; repeating the steps till all assumed values are calculated, and searching for the anisotropic value corresponding to the minimum value in a target function; and repeating the steps till the whole depthinterval is processed to obtain the anisotropic curve of the stratum in the processed depth interval. As a result of instantaneity of measurement while drilling, the processing result is truer and more accurate. The method suppresses the nonuniqueness problem in an inversion process effectively, and the inversion precision is relatively high.

This invention discloses a slowness measurement method for stoneley waves of well holes. In a monopole acoustic logging instrument, the reflection phenomenon of the stoneley wave is very obvious because of the size change of the well hole and the parameter change of the crack and the stratum. Theses reflection waves are influences for the extraction of the slowness of the stoneley waves, and thus relative big errors could be caused. This slowness measurement method for stoneley waves of well holes performs wave filtration on array wave shape so as to eliminate reflection stoneley wave, reduce slowness measurement errors and improve measurement precision.

A method for determining properties of a formation comprises disposing at least one acoustic logging tool in a well and moving the logging tool along the well. An acoustic logging is performed during movement of the acoustic logging tool together with simultaneous thermal treatment of the formation. A temperature of a formation zone being thermally treated is measured as well as attenuation and velocity of the Stoneley waves excited by the acoustic logging tool. Based on the obtained dependencies of measured parameters as functions of the formation zone temperature formation relative phase permeabilities, formation fluid viscosity and viscous flow activation energy are determined.

The invention discloses a method for distinguishing the effectiveness of a reservoir bed through stoneley wave energy loss degree. The method comprises the steps of regarding stoneley wave energy extracted from array acoustic logging information as comprehensive response of stoneley wave energy of stratum rock and stoneley wave energy loss degree in pores, establishing a relational expression between the stoneley wave energy and porosity, working out the stoneley wave energy loss degree in pores, and distinguishing the effectiveness of the reservoir bed according to the stoneley wave energy loss degree. The method not only takes the stoneley wave energy of the stratum rocks into account, but also establishes the relational expression between the stoneley wave energy and the porosity, can work out the loss degree of the stoneley wave energy in the pores of the reservoir bed according to the relational expression, and further distinguishes the effectiveness of the reservoir bed.

The invention discloses a method for detecting a liquid level position based on surface wave mode conversion, and the method comprises the following steps: vertically inserting a cuboid waveguide rod into the bottom of liquid, and exciting a surface wave model on the surface of the waveguide rod by utilizing ultrasonic vibration; enabling the air waveguide rod and the immersion waveguide rod to receive the arrived sound waves; on the surface of the waveguide rod, acquiring the point displacement along the sound wave propagation path, and obtaining the surface acoustic wave speed in the air waveguide rod and the stoneley wave propagation speed in the immersion waveguide rod respectively; and determining the liquid level position according to the time when the stoneley wave reaches the bottom of the waveguide rod and the surface wave speed, the stoneley wave speed and the sound wave excitation position. The invention provides a reliable method for measuring the position of the liquid level, and provides a guidance basis for realizing online detection of the position of the liquid level.