Abstract: Disclosed is a method for detecting a fluid, including at least one step of: measuring by at least one sensor of a wave propagating in an environment of the wave, in order to obtain at least one measured signal, the wave being particularly a mechanical wave; splitting the measured signal over a plurality of split time intervals with a predefined duration in order to obtain samples of the measured signal; computing the temporal coherence of the samples; and determination of the presence of the fluid using the computed temporal coherence.

Abstract: Computing device, computer instructions and method for processing input seismic data d. The method includes receiving the input seismic data d recorded in a first domain by seismic receivers that are towed in water, the input seismic data d including pressure data and/or and particle motion data; generating a model p in a second domain to describe the input data d; processing the model p to generate an output particle motion dataset; and generating an image of the surveyed subsurface based on the output particle motion dataset.

Abstract: A method may include obtaining wellhead temperature data from a wellhead coupled to a wellbore. The method may further include obtaining production data regarding the wellhead. The method may further include obtaining water cut data from the wellhead. The method may further include calibrating a production model for the wellhead based on the production data and the wellhead temperature data to generate a calibrated production model. The method may further include determining a predicted production rate of the wellhead using the calibrated production model, the water cut data, and flowing wellhead temperature data.

Abstract: A downhole tool is positioned in a borehole of a geological formation at a given depth. A formation property is determined at the given depth. The positioning and determining is repeated to form data points of a data set indicative of formation properties at various depths in the borehole. One or more outlier data points is removed from the data set based on first gradients to form an updated data set. One or more properties associated with a reservoir compartment are determined based on second respective gradients associated with the updated data set.

Abstract: Various examples are provided for object identification and tracking, traverse-optimization and/or trajectory optimization. In one example, a method includes determining a terrain map including at least one associated terrain type; and determining a recommended traverse along the terrain map based upon at least one defined constraint associated with the at least one associated terrain type. In another example, a method includes determining a transformation operator corresponding to a reference frame based upon at least one fiducial marker in a captured image comprising a tracked object; converting the captured image to a standardized image based upon the transformation operator, the standardized image corresponding to the reference frame; and determining a current position of the tracked object from the standardized image.

Abstract: A time synchronization system includes: a position information acquisition unit configured to acquire installation position information related to an installation position of a time synchronization target whose time is synchronized; a time synchronization signal acquisition unit configured to receive a positioning signal transmitted from a positioning satellite as a time synchronization signal and acquire, from the time synchronization signal, transmission position information related a position of the positioning satellite and transmission time information at timing when the time synchronization signal is transmitted; and a signal processing unit configured to calculate synchronized time information for the time synchronization target based on the installation position information of the time synchronization target and the transmission position information and transmission time information from the time synchronization signal, and transmit the synchronized time information to the time synchronization target.

Abstract: A method, including: obtaining a seismic dataset that is separated into subsets according to predetermined subsurface reflection angle ranges; performing, with a computer, an acoustic full wavefield inversion process on each of the subsets, respectively, to invert for density and generate respective density models; generating acoustic impedances for each of the subsets, as a function of reflection angle, using the respective density models; and transforming, using a computer, the acoustic impedances for each of the subsets into reflectivity sections, wherein the transforming includes normalizing the reflectivity sections by their respective bandwidth.

Abstract: A method is described for seismic imaging of complex subsurface volumes using prismatic seismic energy. The method receives a seismic dataset and an earth model. The earth model is perturbed such that prismatic reflections will generate perturbed seismic amplitudes in a target area and seismic imaging is performed using the perturbed model. A second seismic image is generated using a second earth model; the second earth model may be the original earth model or a second perturbed model wherein the perturbation generates different seismic amplitudes in the target area. The two seismic images are differenced to generate a prismatic seismic image that can be used to identify geologic features that are poorly illuminated in conventional imaging. The method may be executed by a computer system.

Abstract: Methods are provided for identifying one or more transition characteristics in a hydrocarbon fluid such as asphaltene onset pressure (AOP), bubble point or dew point. A transition characteristic is determined by subjecting the fluid to different pressures or temperatures, conducting NMR tests at the different pressures or temperatures to obtain signals, processing the signals to obtain values of a function of an NMR parameter as a function of pressure or temperature, and analyzing the values to find a discontinuity that identifies the transition characteristic. In embodiments, the NMR parameters may include at least one of a relaxation parameter such as T2 or a T1-T2 ratio, a diffusion parameter and an initial magnetization parameter. In embodiments, dual linear fitting, Bayesian change point detection algorithms, and instantaneous slope analysis may be utilized to analyze the values in order to find a discontinuity.

Abstract: Modeling an elastic stiffness tensor in a transverse isotropic subsurface medium acquires well log data for at least one well passing through the transverse isotropic subsurface medium. The transverse isotropic subsurface medium is divided into an effective anisotropic layer and an isotropic layer. The effective anisotropic layer elastic parameters are modeled, and the isotropic layer elastic parameters are modeled using the effective anisotropic layer elastic parameters and the acquired well log data. The modeled effective anisotropic layer elastic parameters and the modeled isotropic layer elastic parameters are used to upscale the effective anisotropic layer and the isotropic layer into the transverse isotropic subsurface medium comprising a single layer and to determine the five members of the elastic stiffness tensor for the transverse isotropic subsurface medium.

Abstract: In one embodiment, the invention utilizes computer models to calculate predicted spectral estimates that may be encountered during a hydraulic fracturing operation. Seismic events generated by hydraulic fracturing are mapped and displayed upon a graphic user interface. Spectral attributes of selected seismic wave field data from the fracture operation are derived and compared to predicted spectral estimates that match one or more characteristics of the formation. The comparison may be utilized to generate a predicted hydrocarbon content for the fracture zone of the formation and to adjust or alter the hydraulic fracturing operation in order to maximize hydrocarbon recovery.

Abstract: Method and resonant source for generating low-frequency seismic waves. The resonant source includes a frame; a reaction mass configured to oscillate relative to the frame; a resonant suspension system connecting the reaction mass to the frame and including at least a spring; and a spring clamp system connected to the resonant suspension system and configured to modify a resonant frequency of the resonant suspension system. The resonant suspension system is configured to allow the reaction mass to oscillate relative to the frame with a corresponding resonant frequency.

Abstract: A method for mapping remaining hydrocarbon resources in a subsurface reservoir, includes obtaining a map of seismic amplitude difference over a time period based on a survey of the subsurface reservoir, generating an expected trend dataset for the reservoir based on one or more non-water saturation effects detected over the time period by one or more wellbore surveillance techniques at one or more locations in the reservoir, correcting the map of seismic amplitude difference, at least in part, on the expected trend dataset to generate a corrected seismic amplitude map, and using the corrected seismic amplitude difference map to generate a map representative of remaining hydrocarbon resources in the reservoir. Embodiments include a system for performing the method and a medium containing computer executable software instructions for performing the method.

Abstract: The disclosed embodiments include a method, apparatus, and computer program product for providing a geostatistical procedure for simulation of the 3D geometry of a natural fracture network conditioned by well bore observations.

Abstract: Systems and methods for identifying sanding in production wells using time-lapse sonic data. Formation anisotropy can be characterized in terms of shear moduli in a vertical wellbore, e.g., vertical shear moduli C44 and C55 in the wellbore axial planes and horizontal shear modulus C66 in the wellbore cross-sectional plane. Changes in formation anisotropy between different times can provide qualitative indicators of the occurrence of sanding in the production well. Before production begins, the horizontal shear modulus C66 is typically less than the vertical shear modulus C44 or C55 or both. At a subsequent time after sanding occurs, the horizontal shear modulus C66 is typically greater than the vertical shear modulus C44 or C55 or both. By comparing the shear moduli of the vertical wellbore at different times, it is possible to identify the occurrence of sanding in the production well using time-lapse sonic data.

Abstract: A sensor array is positionable in a wellbore penetrating a subterranean formation. The sensor array includes a plurality of seismic sensors disposable about a perimeter of the wellbore and coupleable to a signal measurer with a configuration to provide three component seismic signal measurement within the wellbore. At least two of the seismic sensors are located at different azimuthal angles relative to one another and oriented tangentially to a longitudinal axis of the wellbore so as to receive tangential components of wellbore seismic signals to the exclusion of longitudinal and radial components of the wellbore seismic signals.

Abstract: There is provided a system and method for monitoring of fractured wells and conventional wells to detect leaks. The method comprises interrogating a plurality of resonant tags using a modulated RF signal transmitted from an interrogator, wherein the plurality of resonant tags are dispersed within a channel.

Abstract: A method of estimating stress in an earth formation is disclosed. The method includes: dividing a domain including at least a portion of an earth formation into a first region and a second region; estimating a first vertical stress in the first region and representing the first vertical stress as at least one point load; estimating a second vertical stress in the second region by a point load based method using the first vertical stress; and estimating at least one horizontal stress based on the second vertical stress.

Abstract: Different values of at least one migration parameter are selected. An imaging technique is applied a plurality of times, where each application of the imaging technique uses a corresponding different one of the different values. Each application of the imaging technique produces a corresponding image of a subterranean structure. An aggregate of the images is computed to produce an output image of the subterranean structure.

Abstract: Methods and apparatuses for land seismic survey are provided. The methods and apparatuses utilize spatial derivatives of a seismic wavefield to interpolate, regularize or extrapolate seismic data. The methods and apparatuses may considerably reduce land seismic field efforts and/or compensate data gaps.

Abstract: Various implementations described herein are directed to a method of performing a seismic survey operation. The method may include deploying two seismic sources. The method may include using the two seismic sources to perform a simultaneous in-phase precursor sweep. The method may also include using the two seismic sources to perform a simultaneous out-of-phase cascaded sweep.

Abstract: The present invention relates to a method for synchronizing continuous seismic survey. In particular, the present invention employs a semaphore scheme for the vibes to autonomously and continuously initiate sweeps, thereby decoupling the vibratory source subsystem from the recording subsystem. By using a continuous recorder and the method of the present invention, the recording trucks and the observers can be eliminated, and the vibratory sources can be initiated more efficiently than conventional systems.

Abstract: A seismic land vibrator, comprising a baseplate comprising a substantially flat, rigid member; at least one driven member that is connected with the baseplate and extends in a direction that is substantially perpendicular to baseplate; a rotation sensor that is coupled to the baseplate and adapted to provide a signal that is indicative of rotational movement of at least a portion of the baseplate.

Abstract: An integrated seismic system and method for monitoring seismic parameters of a subsurface structure is provided. The integrated seismic system includes a plurality of mobile satellite nodes, a seismic cable and a base station. Each of the mobile satellite nodes has sensor stations operatively connectable thereto for collecting seismic data from the subsurface structure. The seismic cable operatively links the plurality mobile satellite nodes and the sensor stations. The base station includes a seismic acquisition unit for receiving seismic signals from the mobile satellite nodes via the seismic cable and generating seismic parameters therefrom.

Abstract: Method for using seismic data from earthquakes to address the low frequency lacuna problem in traditional hydrocarbon exploration methods. Seismometers with frequency response down to about 1 Hz are placed over a target subsurface region in an array with spacing suitable for hydrocarbon exploration (21). Data are collected over a long (weeks or months) time period (22). Segments of the data (44) are identified with known events from earthquake catalogs (43). Those data segments are analyzed using techniques such as traveltime delay measurements (307) or receiver function calculations (46) and then are combined with one or more other types of geophysical data acquired from the target region, using joint inversion (308-310) in some embodiments of the method, to infer physical features of the subsurface indicative of hydrocarbon potential or lack thereof (26).

Abstract: Various examples are provided for land streamer seismic surveying using multiple sources. In one example, among others, a method includes disposing a land streamer in-line with first and second shot sources. The first shot source is at a first source location adjacent to a proximal end of the land streamer and the second shot source is at a second source location separated by a fixed length corresponding to a length of the land streamer. Shot gathers can be obtained when the shot sources are fired. In another example, a system includes a land streamer including a plurality of receivers, a first shot source located adjacent to the proximal end of the land streamer, and a second shot source located in-line with the land streamer and the first shot source. The second shot source is separated from the first shot source by a fixed overall length corresponding to the land streamer.

Abstract: A method and system for acquiring seismic data from a seismic survey plan is provided. A survey area is selected in which the seismic data will be acquired. A coordinate for at least one point of interest within the survey area is determined and input into a portable navigation device. A navigation solution is determined between a GPS-determined location of the portable navigation device and the determined coordinate and thereupon presented in a human cognizable media. A seismic device may be positioned at the determined coordinate to insonify a subterranean formation with seismic energy or for detecting reflected seismic energy. Data may be periodically entered into and retrieved from the portable navigation device by an in-field operator. 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.

Abstract: A multimode seismic unit can selectively operate in any one or more of multimode readout modes. In one embodiment, a multimode seismic unit (1600) includes a physical mode selector switch (1602). The mode selector switch (1602) allows for manual selection of output modes including wireless, nodal, dual mode or automatic mode selection. The unit (1600) further includes an antenna (1604) for RF transmissions and a data port (1606) for uploading data in a nodal mode. The multimode unit can be used to implement a variety of single mode and multimode seismic arrays.

Abstract: An apparatus for automated seismic sensing includes a seismic sensing device for sensing seismic vibrations, a robotic transport unit for transporting the seismic sensing device to a targeted location, an engagement unit for placing the seismic sensing device in vibrational communication with the ground, and a recording module for recording the seismic data generated by the seismic sensing device. A corresponding method for automated seismic sensing includes transporting a seismic sensing device to a targeted location with a robotic transport device, determining a coupling metric for the seismic sensing device and the ground at a plurality of locations proximate to the targeted location, determining an acceptable location for seismic sensing, placing the seismic sensing device in vibrational communication with the ground at the acceptable location, and sensing seismic data with the seismic sensing device at the acceptable location.

Abstract: Systems and methods are provided for acquiring data using a wireless network and a number of nodes that may be configured to collect acquired data and forward data to a central recording and control system. The acquired data may include seismic and/or auxiliary data. A node for use in data acquisition may include an acquisition module in operative communication with a buried sensor array operable to output acquired data. The processor may also be operable to receive acquired data from another data acquisition module in the wireless network.

Abstract: According to an embodiment, a seismic receiver device is described for use in a borehole surrounded by an ambient material, e.g., rock, mud, etc. The seismic receiver device includes a pressure wave measuring device which is configured to sense pressure changes associated with received seismic waves, a coating layer disposed on the pressure wave measuring device, and an outer layer disposed on the coating layer which is made of a material that is selected to have a bulk modulus number that is substantially similar to a bulk modulus number of the ambient medium. In this way, the acoustic impedance of the device is better matched to the ambient material so that more accurate seismic acquisition may be performed.

Abstract: A seismic sensor device includes an elongated housing for placement at least partially into an earth surface. A plurality of particle motion sensors are contained in the elongated housing to measure translational data in a first direction, where plural pairs of the particle motion sensors are spaced apart along a second, different direction along a longitudinal axis of the elongated housing. A communication interface communicates the measured translational data to a computer system configured to compute a gradient based on respective differences of the measured translational data of the corresponding plural pairs of the particle motion sensors, and compute one or more of rotation data and divergence data using the gradient.

Abstract: A method and related apparatus are described for generating acoustic signals for use in a vibratory seismic survey, including at least two different sweep signals for the control of at least two different types of vibrators; and matching the phases of the different sweep signals at a transition frequency from one sweep signal to another.

Abstract: Controller and method for generating a frequency sweep for a seismic survey that uses a seismic source. The method includes receiving specification data about the seismic source; receiving environmental data about an infrastructure affected by the seismic survey; receiving guideline data about the infrastructure; setting a target energy spectrum density to be emitted by the seismic source during the seismic survey; and calculating, in a processor, the frequency sweep based on the specification data, environmental data, guideline data and the target energy spectrum density.

Abstract: A sensor device is adapted to be installed at a land-air interface. The sensor device comprises a fluid-filled housing and a sensor arrangement supported within the housing and coupled directly to the fluid so as to detect movement thereof. A seismic sensor installation comprises a sensor device installed at a land-air boundary, wherein the sensor device comprises a fluid-filled housing and a sensor arrangement supported within the housing and coupled directly to the fluid as to detect movement thereof.

Abstract: In one aspect, a seismic data acquisition unit is disclosed including a closed housing containing: a seismic sensor; a processor operatively coupled to the seismic sensor; a memory operatively coupled to the processor to record seismic data from the sensor; and a power source configured to power the sensor, processor and memory. The sensor, processor, memory and power source are configured to be assemble as an operable unit in the absence of the closed housing.

Abstract: In one example, a land based seismic sensing device includes: a seismic sensing unit having a seismic sensor in a housing configured to be buried in the ground; a control unit including a battery in a weather resistant housing configured to be exposed above ground; and a flexible cable mechanically and electrically connecting the seismic sensing unit and the control unit. The cable includes a weather resistant jacket and an electrically conductive element inside the jacket detachably connected between electronic circuitry in the sensing unit and electronic circuitry in the control unit. In one example, the control unit housing includes a first compartment configured to stow the seismic sensing unit and a second compartment configured to stow the cable.

Abstract: A method for improving a 4-dimensional (4D) repeatability by modifying a given path to be followed by a source during a seismic survey. The method includes receiving the given path at a control device associated with a vehicle that caries the source; following the given path during a first seismic survey that is a baseline survey for the 4D seismic survey; deviating from the given path to follow a new path when encountering an obstacle on the given path; and updating the given path, based on the new path, to obtain an updated given path when a deviation condition is met.

Abstract: A self-contained, wireless seismic data acquisition unit having a cylindrically shaped case with smooth side walls along the length of the case. A retaining ring around the circumference is used to secure the cylindrical upper portion of the case to the cylindrical lower portion of the case. Interleaved fingers on the upper portion of the case and the lower portion of the case prevent the upper portion and the lower portion from rotating relative to one another. Ruggedized external electrical contacts are physically decoupled from rigid attachment to the internal electrical components of the unit utilizing electrical pins that “float” relative to the external case and the internal circuit board on which the pins are carried. The seismic sensors in the unit, such as geophones, and the antennae for the unit are located along the major axis of the cylindrically shaped case to improve fidelity and timing functions.

Abstract: A method and system are disclosed for performing seismic surveys using a seismic vibrator, which generates a sweep signal with enhanced low frequency content by generating a combination of a linear and nonlinear sweep and wherein the nonlinear sweep snonl(t) as a function of time (t) is calculated by a predetermined algorithm.

Abstract: A system includes a seismic acquisition system that includes a plurality of nodes and further includes an unmanned airborne vehicle. The unmanned airborne vehicle is to be used with the seismic acquisition system to conduct a seismic survey.

Abstract: Presented are systems and methods for deploying wireless data acquisition modules that facilitate autonomous initialization. The wireless data acquisition modules may initiate a initialization process in response to a stimulus associated with being deployed. The wireless data acquisition module may further conduct a neighbor discovery process and in turn establish a data transfer path among one or more other wireless data acquisition modules. Further, information obtained during a series of autonomous tests may be communicated during the neighbor discovery process and the establishment of the data transfer path may at least in part be based on the information obtained in the autonomous tests.

Abstract: A fiber optic distributed vibration system for detecting seismic signals in an earth formation is provided. The system includes a fiber optic cable deployed in a borehole that extends into the earth formation and which is configured to react along its length to a seismic wave incident on the fiber optic cable from outside the borehole. An optical source launches an optical signal into the fiber optic cable while the seismic wave is incident thereon. A receiver detects coherent Rayleigh noise (CRN) produced in response to the optical signal. A processing circuit processes the detected CRN signal to determine characteristics of the earth formation.

Abstract: Receiver lines arranged in an area to be explored are provided with geophones in respective receiver positions for measuring seismic waves from the subsoil. The receiver lines include first parallel lines and second lines parallel to the first lines and located in intermediate positions between the first lines. Seismic waves are emitted from source positions located along the first receiver lines, and seismic data, representing waves measured by the various geophones in response to the emitted waves, are obtained. Said first seismic data are processed by seismic interferometry in order to estimate other seismic data representing responses, in at least some of the receiver positions, to waves emitted from a virtual source located in a receiver position along a second line.

Abstract: An electric sweep type seismic vibrator source of the type used in seismic prospecting for hydrocarbons is provided. In one example, the source uses an engine and generator combination to create electric power for all systems on the source such as driving a frame of linear electric motors that direct a rod or piston to contact the ground in a recurring fashion along with driving the source from location to location through a survey area. A foot is arranged on the bottom end of the rod or piston for contact with the ground and by engaging the grid of motors to push down against the ground in a rapid progression, acoustic energy is created and delivered into the ground for geophones to sense and record.

Abstract: The invention is an electric sweep type seismic vibrator source of the type used in seismic prospecting for hydrocarbons. The source uses an engine and generator combination to create electric power for all systems on the source such as driving a frame of linear electric motors that direct a rod or piston to contact the ground in a recurring fashion along with driving the source from location to location through a survey area. Preferably a foot is arranged on the bottom end of the rod or piston for contact with the ground and by engaging the grid of motors to push down against the ground in a rapid progression, acoustic energy is created and delivered into the ground for geophones to sense and record.

Abstract: The invention is an electric seismic vibrator source of the type used in seismic prospecting for hydrocarbons that creates a quasi-impulsive burst of seismic energy onto the ground and into the earth. The source uses an engine and generator combination to create electric power for all systems on the source such as driving a frame of linear electric motors that direct a rod or piston to contact the ground. All of the linear electric motors are driven against the ground in a high power pulse that delivers a band-limited spectrum of seismic energy over a very brief period of time that would like a “pop” and be measured in milliseconds. A quasi-impulsive seismic pulse would create a wave field that resembles the seismic data acquired using dynamite or other explosive seismic systems without the ultrahigh frequencies of a true explosive pulse. The quick burst or several quick bursts may further speed up the survey by minimizing the time that a vibe spends on a source point.

Abstract: A seismic sensor unit includes a sensor housing including an inner chamber and a receiver extension for ground coupling, a suspension fluid disposed in the inner chamber, and a hydrophone suspended in the suspension fluid. The seismic sensor unit may include a sensor housing including a steel spike coupled to the ground, a fluid chamber in the sensor housing, a fluid in the fluid chamber, and a hydrophone disposed in the fluid chamber and contacting the fluid such as to detect a pressure wavefield in the fluid caused by ground motion acting on the steel spike. A method includes receiving ground motion at a seismic sensor unit coupled to the ground, transmitting the ground motion to a fluid chamber, creating a pressure wavefield in a fluid in the fluid chamber in response to the ground motion, and detecting the pressure wavefield in the fluid using a hydrophone.

Abstract: This application relates to methods and apparatus for seismic surveying using optical fibre distributed acoustic sensing (DAS). The method involves using a fibre optic distributed acoustic sensor to detect seismic signals. The fibre optic distributed acoustic sensor comprises an interrogator (106) arranged to interrogate at least one optical fibre (104) buried in the ground (204) in the area of interest. The method involves stimulating the ground using a seismic source (201) and detecting the seismic signals, for example reflected from various rock strata (202, 203).

Abstract: A technique includes simulating seismic wave propagation based on an acoustic model and based on a result of the simulation, estimating an error between the result and another result obtained if the seismic wave propagation were simulated based on an elastic model. The technique includes based at least in part on the estimated error predicting the other result without performing the simulation based on the elastic model.