Chevron U.s.a. Inc.

Los Alamos National Security, LLC

Other

Cung Khac Vu

Kurt Nihei

Christopher Hugh Skelt

Paul Allan Johnson

Pierre-Yves Le Bas

Robert A Guyer

Denis P Schmitt

James A Ten Cate

Dipen N Sinha

Cristian Pantea

James P Disiena

Todd C Dygert

Carène S Larmat

Henry W Posamentier

James A Tencate

Caréne S Larmat

Kurt T Nihei

Chirstopher Skelt

C Skelt

Julio De La Colina

Methods for measuring seismic velocities and for monitoring local changes in inter-well seismic velocities in real time are described. Two or more spaced-apart observation wells are provided. Seismic receiver arrays are placed in the observation wells, and a seismic source array is provided at surface locations away from the well bores and producing areas. Compression (P), vertical shear (Sv) and/or horizontal shear (Sh) seismic wave signals are generated from each element of the seismic source array, and the seismic signals arriving at the receivers in the observation wells are recorded. The virtual source method is then applied to the recorded data to compute emulated cross-well seismic signals of the virtual sources at receiver locations in one observation well propagating toward the receivers at other observation wells. Analysis of direct arrivals of emulated cross-well seismic signals can be completed to extract travel times, inter-well seismic velocities, and rock properties.

Measurement of in situ rock formation properties using surface seismic sources and downhole receivers

A system and method for investigating rock formations outside a borehole are provided. The method includes generating a first compressional acoustic wave at a first frequency by a first acoustic source; and generating a second compressional acoustic wave at a second frequency by a second acoustic source. The first and the second acoustic sources are arranged within a localized area of the borehole. The first and the second acoustic waves intersect in an intersection volume outside the borehole. The method further includes receiving a third shear acoustic wave at a third frequency, the third shear acoustic wave returning to the borehole due to a non-linear mixing process in a non-linear mixing zone within the intersection volume at a receiver arranged in the borehole. The third frequency is equal to a difference between the first frequency and the second frequency.

System and method for investigating sub-surface features of a rock formation using compressional acoustic sources

A system and method of characterizing properties of a medium from a non-linear interaction are include generating, by first and second acoustic sources disposed on a surface of the medium on a first line, first and second acoustic waves. The first and second acoustic sources are controllable such that trajectories of the first and second acoustic waves intersect in a mixing zone within the medium. The method further includes receiving, by a receiver positioned in a plane containing the first and second acoustic sources, a third acoustic wave generated by a non-linear mixing process from the first and second acoustic waves in the mixing zone; and creating a first two-dimensional image of non-linear properties or a first ratio of compressional velocity and shear velocity, or both, of the medium in a first plane generally perpendicular to the surface and containing the first line, based on the received third acoustic wave.

System and method for generating 3D images of non-linear properties of rock formation using surface seismic or surface to borehole seismic or both

An acoustic source for generating an acoustic beam includes a housing; a plurality of spaced apart piezo-electric layers disposed within the housing; and a non-linear medium filling between the plurality of layers. Each of the plurality of piezoelectric layers is configured to generate an acoustic wave. The non-linear medium and the plurality of piezo-electric material layers have a matching impedance so as to enhance a transmission of the acoustic wave generated by each of plurality of layers through the remaining plurality of layers.

Acoustic source for generating an acoustic beam

A method and system includes generating a first coded acoustic signal including pulses each having a modulated signal at a central frequency; and a second coded acoustic signal each pulse of which includes a modulated signal a central frequency of which is a fraction d of the central frequency of the modulated signal for the corresponding pulse in the first plurality of pulses. A receiver detects a third signal generated by a non-linear mixing process in the mixing zone and the signal is processed to extract the third signal to obtain an emulated micro-seismic event signal occurring at the mixing zone; and to characterize properties of the medium or creating a 3D image of the properties of the medium, or both, based on the emulated micro-seismic event signal.

System and method for generating micro-seismic events and characterizing properties of a medium with non-linear acoustic interactions

Geologic information may be extracted from multiple offset stacks and/or angle stacks. Offset stacks and/or angle stacks may be received that represent energy that has propagated through a geologic volume of interest from energy sources to energy receivers. Attribute volumes associated with individual source-receiver offsets and/or source-receiver angles may be determined based on corresponding offset stacks and/or angle stacks. For individual offset stacks or angle stacks, corresponding sets of geologic features represented in the attribute volumes may be identified. The sets of geologic features corresponding to the different offset stacks and/or angle stacks to may be compared to determine discrepancies and/or similarities between the sets of geologic features corresponding to the different offset stacks and/or angle stacks. Stratigraphic interpretations, stratigraphic predictions, and/or other interpretations and/or predictions may be determined based on causes of the discrepancies and/or similarities.

Extracting geologic information from multiple offset stacks and/or angle stacks

A system for investigating non-linear properties of a rock formation around a borehole is provided. The system includes a first sub-system configured to perform data acquisition, control and recording of data; a second subsystem in communication with the first sub-system and configured to perform non-linearity and velocity preliminary imaging; a third subsystem in communication with the first subsystem and configured to emit controlled acoustic broadcasts and receive acoustic energy; a fourth subsystem in communication with the first subsystem and the third subsystem and configured to generate a source signal directed towards the rock formation; and a fifth subsystem in communication with the third subsystem and the fourth subsystem and configured to perform detection of signals representative of the non-linear properties of the rock formation.

Integrated system for investigating sub-surface features of a rock formation

A method of interrogating a formation includes generating a conical acoustic signal, at a first frequency&#x2014;a second conical acoustic signal at a second frequency each in the between approximately 500 Hz and 500 kHz such that the signals intersect in a desired intersection volume outside the borehole. The method further includes receiving, a difference signal returning to the borehole resulting from a non-linear mixing of the signals in a mixing zone within the intersection volume.

System and method for investigating sub-surface features of a rock formation with acoustic sources generating conical broadcast signals

A method and system for investigating structure near a borehole are described herein. The method includes generating an acoustic beam by an acoustic source; directing at one or more azimuthal angles the acoustic beam towards a selected location in a vicinity of a borehole; receiving at one or more receivers an acoustic signal, the acoustic signal originating from a reflection or a refraction of the acoustic wave by a material at the selected location; and analyzing the received acoustic signal to characterize features of the material around the borehole.

System and method for sonic wave measurements using an acoustic beam source

Self-consistency and/or differences between volume images and interpreted spatial/volumetric context may be exploited for improving seismic imaging and estimation of attributes of geobodies, in accordance with one or more embodiments. Exemplary embodiments allow exploitation of positional and/or shape discrepancies and/or similarities of geobodies in image volumes associated with a geologic model of a geologic volume of interest to improve the accuracy of the geologic model and/or the image volumes. Constraints associated with the geologic volume of interest may be determined and/or utilized to confirm and/or specify dependencies between attributes that are potentially associated with individual geobodies.

Exploitation of self-consistency and differences between volume images and interpreted spatial/volumetric context

A system and a method for generating a three-dimensional image of a rock formation, compressional velocity VP, shear velocity VS and velocity ratio VP/VS of a rock formation are provided. A first acoustic signal includes a first plurality of pulses. A second acoustic signal from a second source includes a second plurality of pulses. A detected signal returning to the borehole includes a signal generated by a non-linear mixing process from the first and second acoustic signals in a non-linear mixing zone within an intersection volume. The received signal is processed to extract the signal over noise and/or signals resulting from linear interaction and the three dimensional image of is generated.

System and method for investigating sub-surface features and 3D imaging of non-linear property, compressional velocity VP, shear velocity VS and velocity ratio VP/VS of a rock formation

A system and a method includes generating a first signal at a first frequency; and a second signal at a second frequency. Respective sources are positioned within the borehole and controllable such that the signals intersect in an intersection volume outside the borehole. A receiver detects a difference signal returning to the borehole generated by a non-linear mixing process within the intersection volume, and records the detected signal and stores the detected signal in a storage device and records measurement parameters including a position of the first acoustic source, a position of the second acoustic source, a position of the receiver, elevation angle and azimuth angle of the first acoustic signal and elevation angle and azimuth angle of the second acoustic signal.

Data acquisition and processing system and method for investigating sub-surface features of a rock formation

A system and a method for investigating rock formations includes generating, by a first acoustic source, a first acoustic signal comprising a first plurality of pulses, each pulse including a first modulated signal at a central frequency; and generating, by a second acoustic source, a second acoustic signal comprising a second plurality of pulses. A receiver arranged within the borehole receives a detected signal including a signal being generated by a non-linear mixing process from the first-and-second acoustic signal in a non-linear mixing zone within the intersection volume. The method also includes-processing the received signal to extract the signal generated by the non-linear mixing process over noise or over signals generated by a linear interaction process, or both.

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Houston, TX, United States of America

Cung Khac Vu