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.

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.

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 method for determining properties of a formation is described herein. The method includes disposing a well-logging tool in a borehole. The well-logging tool includes a device for varying temperature of the formation and two acoustic logging probes located symmetrically along the well-logging tool length relative to the device for varying temperature of the formation. During the logging tool movement in the borehole, continuous varying of the formation temperature, continuous acoustic logging, and continuous measurement of formation temperature are performed. Dependencies of the measured velocity and attenuation of the Stoneley waves as functions of the measured temperature of the formation are obtained. Based on the obtained dependencies, properties of the formation are determined.

The invention provides a novel calculating method for the rigidity coefficient of a stratum. The method comprises the following steps: performing acoustic anisotropy measurement and volume density calculation on rock core samples to obtain a stiffness coefficient and a longitudinal wave anisotropy coefficient; performing X-diffraction measurement on the rock core samples to obtain clay content; building a relation between the longitudinal wave anisotropy coefficient and the clay content; building relations between a C11 rock core and a C33 rock core as well as between a C44 rock core and a C66 rock core; calculating the clay content by using conventional logging data of a target level of a target well; calculating the rigidity coefficients of C33 ground and C44 ground of the stratum by using the longitudinal and shear wave velocities and a volume density logging curve of the target level of the target well; calculating the rigidity coefficient C11 ground of the stratum according to the relation between the longitudinal wave anisotropy coefficient and the clay content, the clay content of the stratum and the rigidity C33 ground of the stratum; calculating the rigidity coefficient C66 ground of the stratum according to the relations between the C11 rock core and the C33 rock core as well as between the C44 rock core and the C66 rock core, the C33 ground, the C44 ground and the C11 ground. By adopting the novel calculating method, the rigidity coefficient can be calculated without utilizing a horizontal shear wave velocity obtained by performing reverse calculation on extracted stoneley waves, the extracting process of horizontal shear waves is avoided, and the calculation is easy, convenient and efficient.

The invention discloses a method for detecting interlamination transverse cracks of a carbon steel / aluminum explosion composite pipe. The method comprises the following steps: exciting to generate and receive guided wave signals at an end surface of the carbon steel / aluminum explosion composite pipe by using Stoneley ultrasonic interface guided waves suitable for analyzing interface problems; then analyzing excitation signals and a plurality of received signal waves, and realizing positioning of interlamination cracks according to a propagation time difference method by using the characteristic that Stoneley waves do not have frequency dispersion; and obtaining an amplitude ratio by using excitation signal amplitude and reflected signal amplitude, changing the excitation frequency for a plurality of times to obtain a plurality of signal amplitude ratio numerical values corresponding to different frequencies, and drawing a relation curve of the signal amplitude ratio and wavelength, wherein the wavelength of the Stoneley waves corresponding to a turning point from a slowly decreasing zone to a quickly decreasing zone of the curve is a quantitative estimated value of the sizes of the interlamination transverse cracks. The detection method disclosed by the invention is reliable in result and simple and feasible to operate, and is suitable for parameter quantitative identification of the interlamination transverse cracks of the carbon steel / aluminum explosion composite pipe.