Patent classifications
G01V2210/54
Correcting for eccentricity of acoustic sensors in wells and pipes
A device and method used to correct beamforming of an acoustic phased array in cases of eccentricity of the acoustic device in a tubular. A processor calculates the eccentricity from multiple scan lines and create a geometric model of a well or pipe relative to the device. The processor may correct each scan line's focus and/or angle of incidence at a surface of the well or pipe based on the observed eccentricity.
Imaging with both dipole and quadrupole receivers
A method and system for locating a reflector in a formation. The method may comprise broadcasting a sonic waveform as a shear formation body wave or a compressional formation body wave into the formation, recording a reflected wave from a reflector with the one or more receivers as dipole data by the dipole receiver and quadrupole data by the quadrupole receiver, and processing the dipole data and the quadrupole data with an information handling system to determine a location of the reflector from the borehole sonic logging tool. The system may comprise a borehole sonic logging tool and an information handling system. The borehole sonic logging tool may comprise one or more transmitters configured to transmit a sonic waveform into a formation and one or more receivers configured to record a reflected wave as a dipole receiver for dipole data and a quadrupole receiver for quadrupole data.
Real-Time Tool Mode Waveform Removal
Methods and systems for removing tool mode waveforms. The method may include disposing a bottom hole assembly (BHA) into a wellbore. The BHA may comprise at least one transmitter configured to transmit a pressure pulse and at least one receiver configured to record one or more waveforms. The method may further comprise performing a logging-while-drilling (LWD) operation in which the one or more waveforms are recorded with the at least one receiver, transmitting the one or more waveforms to an information handling system, removing one or more tool mode waveforms from the one or more waveforms to form an updated set of waveforms, and forming differential phase time semblance map based at least in part on the updated set of waveforms. The system may comprise the BHA and information handling system configured to remove one or more tool mode waveforms.
Method of Minimizing Tool Response for Downhole Logging Operations
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.
Tool for azimuthal resistivity measurement and bed boundary detection
Systems and methods for performing bed boundary detection and azimuthal resistivity logging using a logging tool with a pair of tilted receiver antennas having a midpoint on a longitudinal axis of the logging tool, a first pair of transmitter antennas symmetrically spaced from said midpoint, and a third tilted receiver antenna positioned farther from said midpoint than the transmitter antennas. Method embodiments include energizing each transmitter antenna of the first pair in a firing sequence and obtaining, responsive to the energizing, measurements with a pair of tilted receiver antennas equally spaced from said midpoint. Methods may also include obtaining, responsive to energizing of a more distant one of the first pair of transmitter antennas, measurements with a third tilted receiver antenna positioned farther from the midpoint than the transmitter antennas.
B annulus acoustic pressure sensing
A method and apparatus for determining a pressure in an annulus between an inner casing and an outer casing. An acoustic transducer is disposed within the casing at a selected depth within the inner casing and is configured to generate an acoustic pulse and receive a reflection of the acoustic pulse from the inner casing. A time of flight is measured of the acoustic pulse to the inner surface of the inner casing. An inner diameter of the inner casing is determined from the time of flight. The pressure in the annulus is determined from the inner diameter. A processor can be used to measure time and determine inner diameter and annulus pressure.
REDUCTION OF A TOOL WAVE EXCITED BY A TRANSMITTER OF A WELL LOGGING TOOL
A logging tool for performing well logging activities in a geologic formation has one or more transmitters, one or more receivers, and a tool wave propagating factor which differs from a formation wave propagating factor. The one or more transmitters excite a tool wave and formation wave. The tool wave is reduced by the one or more transmitters transmitting an acoustic wave which causes the tool wave to be reduced. Additionally, or alternatively, the tool wave is reduced by generating an inverse estimate of the tool wave based on waveform data associated with the tool wave and formation wave received by each of the one or more receivers.
Reduction of a tool wave excited by a transmitter of a well logging tool
A logging tool for performing well logging activities in a geologic formation has one or more transmitters, one or more receivers, and a tool wave propagating factor which differs from a formation wave propagating factor. The one or more transmitters excite a tool wave and formation wave. The tool wave is reduced by the one or more transmitters transmitting an acoustic wave which causes the tool wave to be reduced. Additionally, or alternatively, the tool wave is reduced by generating an inverse estimate of the tool wave based on waveform data associated with the tool wave and formation wave received by each of the one or more receivers.
METHOD FOR FRACTURING ACTIVITY AND INTENSITY MONITORING AND PRESSURE WAVE RESONANCE ANALYSIS
A method for characterizing a hydraulic fracture treatment both operationally and in a subsurface formation includes inducing a pressure change in a well drilled through the subsurface formation. At least one of pressure and a time derivative of pressure is measured in the well for a selected length of time. At least one physical parameter of at least one fracture is determined using the measured pressure and/or the time derivative of pressure. A method of evaluating hydraulic fracturing treatment and operations by monitoring resonant structures present while fracturing.
Downhole Ultrasound Image Correction in Oil Based Mud
A method for generating acoustic images corrected for distortions caused by attenuation of the ultrasonic signal by the mud may comprise disposing a downhole tool into a borehole, transmitting a pressure pulse from at least one transducer into the borehole, recording an echo with the at least one transducer, measuring a travel time, measuring an amplitude, determining a geometry of the borehole, determining a location of the downhole tool in the borehole, calculating an incident angle, mapping a mud attenuation, and correcting an image. A system for generating acoustic images corrected for distortions caused by attenuation of the ultrasonic signal by the mud comprising a downhole tool that may comprise a measuring assembly, wherein the measuring assembly comprises at least one transducer and wherein the at least one transducer is configured to emit a pressure pulse and record an echo. The system may further comprise an information handling system.