Abstract: A seismic sensor includes a measurement unit configured to measure acceleration; an earthquake determination unit configured to determine whether or not an earthquake has occurred based on the acceleration measured in a predetermined determination period; an index calculator configured to calculate an index value indicating a scale of an earthquake in an earthquake processing period after the predetermined determination period, when the earthquake determination unit determines that an earthquake has occurred; a continuous earthquake determination unit configured to determine whether or not an earthquake has occurred, based on the acceleration measured in the earthquake processing period; and a shut-off determination unit configured to inhibit output of the shut-off signal regardless of the index value when the continuous earthquake determination unit determines that no earthquake has occurred.

Abstract: A housing for a seismic sensor station has a base and a removable lid, which when assembled together form a shell whereby the base and the removable lid both have a shell side and an exterior side. A sensor spike, protruding outward from the shell, may be attached to the base on the exterior side of the base. The housing is further provided with two cable docking ports, each allowing passage of a fiber optical cable from outside to inside the shell. The two cable docking ports are exclusively provided in the removable lid.

Abstract: A method of determining an earthquake event for an earthquake detecting system includes retrieving at least one initial wave characteristic related to each earthquake data among a plurality of earthquake data; utilizing a support vector classification (SVC) method to establish an earthquake determination model according to the initial wave characteristic; and determining whether new earthquake data belong to an earthquake event or a non-earthquake event according to the earthquake determination model when the new earthquake data are received.

Abstract: The seismometer uses the interference between light emerging from two closely spaced slits to create an interference pattern. A light detector is used to detect the amplitude of the interference pattern at a specific spatial position. One slit is part of a support for the seismometer, and the other slit is on a pendulum suspended from the support. Vibrations from an earthquake are communicated much better to the slit which is part of the support as compared to the slit on the pendulum. Thus, the vibrations result in a relative movement between the slits and this change in separation between the slits results in the interference pattern from the slits to move. The change in the interference pattern changes the amplitude at the light detector, thereby providing a detectable measurement of vibrations.

Abstract: Power consumption of a seismic sensor is suppressed. The seismic sensor is operated in a power-saving mode and a measuring mode in which the power consumption is larger than that of the power-saving mode. The seismic sensor includes: a measuring part configured to measure an acceleration; an index calculator configured to transition from the power-saving mode to the measuring mode to calculate an index value indicating a size of an earthquake when the acceleration measured with the measuring part exceeds a first threshold; and a threshold adjuster configured to change the first threshold so as to increase the first threshold relative to a predetermined reference value when a tendency of the acceleration measured with the measuring part satisfies a predetermined condition.

Abstract: Extensions exited from electrodes of an electroscan probe, allowing for operation in a wide range of pipe sizes, particularly large diameter pipes, by extending the maximum effective distance of the electric fields generated by the probe. The extensions preferably extend radially from each of the electrodes, and are sized to bring tips of the extensions close to the pipe wall. The extensions can be joined by lanyards to assist in keeping them spaced apart. At least some extensions preferably have bulbous tips, preferably at least partially formed of non-conductive material to keep adjacent extensions from touching each other, especially extensions coupled to different electrodes. The extensions, in one embodiment, are threaded into collars adjacent to each electrode and selected to have a length appropriate for the pipe diameter.

Abstract: The present application relates to a seismic sensor coupling device and method. Translational data in a first direction is measured by particle motion sensors contained in an elongated housing of a sensor device provided at an earth surface. The particle motion sensors are spaced apart along a second, different direction along a longitudinal axis of the elongated housing. Rotation data around a third direction is computed based at least in part on computing a gradient of the translational data with respect to the second direction. Coupling of the sensor to the earth and features related thereto are addressed in the present application.

Abstract: A sensor device includes an elongated housing containing particle motion sensors spaced apart along a longitudinal axis of the elongated housing, where the elongated housing has a length that is greater than a width of the elongated housing. A second portion includes communication circuitry to communicate over a communication medium, the second portion coupled to the elongated housing and having a width that is greater than the width of the elongated housing.

Abstract: A user equipment, an earthquake alert server and an earthquake alert method thereof are provided. The earthquake alert server divides a map into a plurality of geographic grids and receives earthquake reporting messages from a plurality of user equipments. The earthquake alert server monitors the number of reporting messages of each geographic grid within a time interval to determine candidate earthquake grids, and determines earthquake grids according to the adjacent relationship among the candidate earthquake grids. The earthquake alert server chooses any two of the earthquake grids to classify the earthquake grids into two groups and increases a far value of each earthquake grid in the group whose reporting time is later. After multiple choices, the earthquake alert server labels the earthquake grid having the smallest far value as the epicenter grid and transmits an earthquake alert message to a plurality of remote equipments accordingly.

Abstract: Respective embodiments disclosed herein include methods and apparatuses (1) for surveying a mine bench or other material body using at least seismic data obtained via geophone and measurement module data synchronized via a wireless link; (2) for generating hyperspectral panoramic imaging data of a blast hole or other borehole; or (3) for allowing a neural network to facilitate a differential blast design that targets a first bench part more weakly than the differential blast design targets a second bench part (along the same mine bench) at least partly based on data indicative of a much higher concentration of a valuable material in the second bench part than in the first.

Abstract: In one example, a system and method for correlating first well log data with a previously generated well with second well log data from an actively drilling well. A identifying a starting depth is identified above a geological formation. The first well log data is dynamically gain adjusted to the second well log data. The gain adjusted first well log data is dynamically depth warped to the second well log data to correlate the first well log data with the second well log data.

Abstract: Embodiments, including apparatuses, systems and methods, for attaching autonomous seismic nodes to a deployment cable. In an embodiment, an apparatus includes a seismic node having a direct attachment mechanism configured to directly attach the seismic node to a deployment line, the direct attachment mechanism being configurable between an open and/or unlocked position and a closed and/or locked position to release and retain the deployment line.

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: A system and method of performing a microseismic fracture operation for a wellsite having a subterranean formation with a complex fracture network therein are provided. The method involves describing a relationship between microseismic events to determine the complex fracture network of the subterranean formation, generating a fault volume by extracting faults from the fracture network based on the relationship between the microseismic events, generating a discrete fracture network comprising discrete fractures from the complex fracture network by extracting fracture planes from the obtained fault volume, and simulating fracture geometry and proppant placement.

Abstract: An apparatus (100) for deploying and retrieving seismic nodes (200) comprises a towing connection (101) connecting the apparatus (100) to a towing cable (10) running from a towing vessel; vertical control means (125; 5; 120, 12) for adjusting a height over the seafloor by means of the towing cable (10); horizontal control means (125; 130-133) for adjusting a horizontal position according to the desired path and deployment and retrieval means (151; 160, 170, 180) for deploying and receiving nodes (200) connected to a wire (150) at predetermined intervals along the path. The deployment means are preferably configured to deploy the nodes (150) without substantial pull from the previously deployed wire (150).

Abstract: Systems, methods, and software for determining properties of a medium surrounding an exterior portion of a well casing are described. In some aspects, the properties of the medium are determined based on measurements of detected acoustic energy and distances between one or more acoustic transmitters and two or more acoustic receivers. The measurements are obtained based on operating the transmitters and the receivers within a wellbore that includes the well casing.

Abstract: An illustrative geophone with tunable resonance frequency includes a first inductive assembly including an inductive coil having a first magnet arranged therein, wherein the first magnet and the first inductive coil move relative to each other, and a second inductive assembly including a second inductive coil having a second magnet arranged therein, wherein the second magnet and the second inductive coil move relative to each other. A coupling element couples a movable element of the first inductive assembly with a moveable element of the second inductive assembly. The first inductive assembly employs tunable damping to modify a resonant frequency of the second inductive assembly.

Abstract: Measurement data is received from first and second seismic sensors, where the first and second seismic sensors are oriented in opposite directions. Each of the first and second seismic sensors has a sensing element responsive to pressure and particle motion. The signals can be combined to remove the particle motion component of the measurement data and obtain pressure-only data. Alternatively, the signals can be combined to deghost the received measurement data.

Abstract: Disclosed is an optical seismic sensor system for measuring seismic events in a geological formation, including a surface unit for generating and processing an optical signal, and a sensor device optically connected to the surface unit for receiving the optical signal over an optical conduit. The sensor device includes at least one sensor head for sensing a seismic disturbance from at least one direction during a deployment of the sensor device within a borehole of the geological formation. The sensor head includes a frame and a reference mass attached to the frame via at least one flexure, such that movement of the reference mass relative to the frame is constrained to a single predetermined path.

Abstract: The present disclosure generally relates to the use of a self-propelled underwater vehicle for seismic data acquisition. The self-propelled underwater vehicle is adapted to gather seismic data from the seafloor and transmit such data to a control vessel. The self-propelled underwater vehicle may be redeployed to several seafloor locations during a seismic survey. Methods for real-time modeling of a target zone and redeployment of the self-propelled underwater vehicle based on the modeling are also described.

Abstract: An apparatus and system for acquiring seismic data over a loose surface is disclosed. The apparatus includes a housing capable of moving on the loose surface with an opening configured at a bottom surface of the housing. The apparatus further includes a seismic sensing unit configured within the housing at an angle with respect to a horizontal plane. The horizontal plane may be the bottom surface of the housing. The seismic sensing unit is operable to retractably move within the housing towards and away from the opening. In response to the seismic sensing unit moving towards the opening, the seismic sensing unit establishes contact with the loose surface for acquiring the seismic data.

Abstract: A container data center includes a container, a plurality of power supplies, an electric switch system, a plurality of normally closed switches, an alarm device, and a controller. The electric switch system is received in the container. The plurality of normally closed switches are connected between the power supplies and the electric switch system. Each normally closed switch is connected with a corresponding one of the power supplies in series. The controller is connected to the normally closed switches and the alarm device, configured for receiving earthquake information containing an earthquake intensity, and configured for controlling the alarm device to activate alarms and controlling some of the normally closed switches or all the normally closed switches to open when the earthquake intensity is equal to or greater than a predetermined earthquake intensity.

Abstract: A deployment method and system for ocean bottom seismometers (OBS) includes providing a plurality of circular shaped, wireless, self-contained OBS units. The circular shaped OBS units are loaded into a carrier and transported from a surface vessel to the ocean floor where a remotely operated vehicle (ROV) is utilized to individually place the plurality of circular OBS units on the ocean floor. Placement of each OBS unit is accomplished by utilizing suction mechanism attached to a robotic arm. The suction mechanism is defined about an axis and employs a suction cup to individually engage each circular shaped OBS unit so that the suction mechanism is coaxially aligned with the OBS unit, and move the OBS unit from a first location to the ocean floor.

Abstract: A vibration sensor system for contacting the surface of a solid medium for detecting horizontally polarized shear waves and compressional waves. At least two contact points interface between a vibration sensor array and the solid medium to provide uninterrupted contact with the medium during detection of dynamic motions in the medium. A single vibration sensor is mounted on at least two adjacent contact points to convert detected dynamic motions to corresponding electrical signals. The single vibration sensor mounted on the two adjacent contact points forms a sub-array. The vibration sensor system has at least two sub-arrays. A conditioning and combining member treats sensor electrical signals from at least two sub-arrays to form a composite output signal for the system.

Abstract: A deployment and retrieval apparatus for ocean bottom seismic receivers, the apparatus being a remotely operated vehicle (ROV) having a carrier attached thereto and carrying a plurality of receivers. The carrier comprises a frame in which is mounted a structure for seating and releasing said receivers. The structure may comprise a movable carousel or a movable conveyor or fixed parallel rails or a barrel. The structure includes a discharge port on said frame and a discharge mechanism for removing and retrieving said receivers. A method for deployment and retrieval of ocean bottom seismic receivers comprises the steps of loading a carrier with a plurality of receivers, attaching said carrier to an ROV, utilizing said ROV to transport the carrier from a surface vessel to a position adjacent the seabed and thereafter utilizing said ROV to remove receivers from said carrier and place the receivers on the seabed.

Abstract: A sensor vehicle of the present invention has one or more rotatable track means (parallel if two or more) spaced apart by a support frame and adapted to be towed or otherwise moved in a forward direction parallel to a forward axis of said track means. Rotatable track means have two or more supporting wheels aligned on a vertical plane along the forward axis, which axis is generally parallel to a ground surface upon which said sensor vehicle travels. Tracked vehicles are well known in the art of ground and earth moving equipment having flexible, elastomer-based tracks or segmented metal tracks with associated support frames and wheels, most of which may be adapted to achieve the objects of the invention.

Abstract: A marine seismic exploration method and system comprised of continuous recording, self-contained ocean bottom pods characterized by low profile casings, An external bumper is provided to promote ocean bottom coupling and prevent fishing net entrapment. Pods are tethered together with flexible, non-rigid, non-conducting cable used to control pod deployment. Pods are deployed and retrieved from a boat deck configured to have a storage system and a handling system to attach pods to cable on-the-fly. The storage system is a juke box configuration of slots wherein individual pods are randomly stored in the slots to permit data extraction, charging, testing and synchronizing without opening the pods. A pod may include an inertial navigation system to determine ocean floor location and a rubidium clock for timing. The system includes mathematical gimballing. The cable may include shear couplings designed to automatically shear apart if a certain level of cable tension is reached.

Abstract: A seismic vibrator has a base plate with at least four isolators isolating a frame from the base plate. Each of these isolators is offset from the plate's footprint on shelves to free up area on the plate's top surface. An accelerometer disposed directly on the base plate detects the acceleration imparted to the plate. To reduce flexing and bending, the plate has an increased stiffness and approximately the same mass of a plate for a comparably rated vibrator. The accelerometer disposes at a particular location of the plate that experiences transition between longitudinal flexing along the plate's length. This transition location better represents the actual acceleration of the plate during vibration and avoids overly increased and decreased acceleration readings that would be obtained from other locations on the plate.

Abstract: The present disclosure generally relates to the use of a self-propelled underwater vehicle for seismic data acquisition. The self-propelled underwater vehicle is adapted to gather seismic data from the seafloor and transmit such data to a control vessel. The self-propelled underwater vehicle may be redeployed to several seafloor locations during a seismic survey. Methods for real-time modeling of a target zone and redeployment of the self-propelled underwater vehicle based on the modeling are also described.

Abstract: The invention generally relates a method of determining completion criteria for a coal bed methane reservoir having a plurality of coal seams.

Abstract: In one aspect of the invention, a downhole tool string component comprises a tubular body with a first and a second tool joint adapted to connect to adjacent tool string components, and a central bore adapted to pass drilling mud between the joints. A sleeve circumferentially disposed about an outer surface of the tubular body. The sleeve is rigidly attached to the outer surface at first and second sleeve ends and forming at least three stabilizer blades. A nuclear source and at least one nuclear detector are disposed within a gap formed between the inner surface of the sleeve and the outer surface of the tubular body.

Abstract: The current invention minimizes the energy losses by pointing the geophone's internal system, which consists of a magnet bar, coil, and springs, towards signals reflected from targets.

Abstract: Interrogation of a phase based transducer is performed by comparing the state of the transducer at two points in time to determine the rate of change with time of the measurand represented as a phase change. The rate of change, or derivative of the phase change typically has a much smaller amplitude than the signal itself, and the derivative measurement can therefore be thought of as a low sensitivity measurement to be used instead of or in combination with the normal signal measurement having higher sensitivity. In this way, large amplitude signals which might otherwise be subject to overscaling effects can be measured more effectively. For a signal with the majority of its energy centred at approximately 800 Hz, for example, the derivative of that signal will typically be attenuated by 60 dB with a period between the two measurement times of 200 ns.

Abstract: An acoustic isolator for attenuating through-tool acoustic signals comprises a plurality of u-shaped link members, where each link member has two sets of ears. A plurality of yoke members are adapted to fit between cooperating sets of ears. A plurality of pins connect the plurality of u-shaped link members to the plurality of yoke members for providing limited flexural compliance. The isolator may be made from metallic and/or composite materials.

Abstract: The present invention relates to an improved autonomous node seismic recording device having an integrated modular design and one or more features that assist coupling of the unit to the sea floor in order to improve the vector fidelity of seismic signal measurement.

Abstract: A piezo cable is provided as an impact sensor, which allows up to four different measuring principles. In addition to the piezoelectric measurement, which causes a piezoelectric pulse in an impact, a capacitive measurement, an inductive measurement and a resistance measurement are possible.

Abstract: Seismic sensor systems and sensor station topologies, as well as corresponding cable and sensor station components, manufacturing and deployment techniques are provided. For some embodiments, networks of optical ocean bottom seismic (OBS) stations are provided, in which sensor stations are efficiently deployed in a modular fashion as series of array cable modules deployed along a multi-fiber cable.

Abstract: In the present invention, a seismic receiver contains an onboard digitizer that samples and converts a signal from detected seismic energy into the digital domain. The receiver contains an analog to digital converter, a transmission circuitry, and a link to the seismic detection circuitry. The signal from the seismic detection circuitry is converted into a digital signal, which is then relayed to the data recorder. These components are all resident to the receiver itself. Additional control circuitry is employed to provide clocking and testing functions. These receivers communicate with one another, and provide sampled seismic data on an individual basis. The components may be prepared on a PCB and put inside the receiver cap. The PCB may be flexible in nature, as to provide a maximum of surface mounted components in the smallest amount of space.

Abstract: An acoustic logging tool sleeve with a preferably discontinuous, alternating structure that is acoustically opaque in some zones, and acoustically transparent in others. The sleeve may be modular, with several stages connected together. The multiple stages provide a sleeve that may be useful with a variety of borehole logging tools to reduce or eliminate the transmission of noise to the receiving elements.

Abstract: Seismic emission system for use in an underground formation, using at least one seismic source movable successively in a plurality of prepared activation locations and method for implementing same. The system comprises for example a plurality of coupling devices (1) including each for example two anchor elements (12, 9?) tightly coupled with the formation (by cementing for example). These anchor elements are secured to the seismic source (V) such as a vibrator of any type or an impulsive source by transmission elements (10, 13). The seismic source is coupled with coupling device (1) by fast locking means (18, 19). Coupling devices (1) can be preinstalled at a plurality of prepared activation locations above the formation to be monitored. Seismic monitoring operations can be carried out by moving at least one seismic source successively between the different locations where coupling devices (1) are installed.

Abstract: A seismic sensor for a security system is described, the sensor comprising: a piezoelectric transducer suitable for converting mechanical stresses into electrical signals; a base structure including a seat suitable for receiving said transducer; a cover element that can be coupled with the base structure to define an inner chamber of said sensor. The sensor is wherein the cover element has an essentially bell-shaped body, is equipped with a bottom opening and includes side walls that extend around an axis of said opening, the base structure being provided with a collar that surrounds said seat and that crosses said bottom opening so as to define at least one channel communicating with said chamber between the side walls of said cover element and said collar.

Abstract: A marine seismic exploration method and system comprised of continuous recording, self-contained ocean bottom pods characterized by low profile casings. An external bumper is provided to promote ocean bottom coupling and prevent fishing net entrapment. Pods are tethered together with flexible, non-rigid, non-conducting cable used to control pod deployment. Pods are deployed and retrieved from a boat deck configured to have a storage system and a handling system to attach pods to cable on-the-fly. The storage system is a juke box configuration of slots wherein individual pods are randomly stored in the slots to permit data extraction, charging, testing and synchronizing without opening the pods. A pod may include an inertial navigation system to determine ocean floor location and a rubidium clock for timing. The system includes mathematical gimballing. The cable may include shear couplings designed to automatically shear apart if a certain level of cable tension is reached.

Abstract: A pressure gradient sensor for seismic and other applications utilizing the principle of diamagnetic drift. The sensor comprises at least one transducer, each transducer made of or containing a medium having at least one species of mobile charged particles such as electrons or holes that exhibit diamagnetic drift under a pressure gradient. A magnet and a pair of electrodes are installed in each transducer. Diamagnetic drift current collected by the electrodes can be measured by an ammeter or similar device, and formulas and methods are disclosed to determine the pressure gradient from the measured current.

Abstract: A housing for a seismic sensing element (3) for use on the earth's surface comprises connecting means (5) for connecting the housing (3) to a support cable (2) so as to allow relative movement between the sensor housing (3) and the cable (2). This de-couples the sensor housing from the support cable, and improves the fidelity of the sensor. The connecting means (5) preferably comprises resilient connecting elements, to prevent the transmission of vibrations between the support cable and the sensor housing. The sensor housing (3) preferably has a flat base (1), so that there is good coupling between the sensor housing and the earth. Alternatively, the sensor housing can be fitted with a base member ((24a, 24b, 24c) that has at least one flat face (26, 26a, 26b, 26c).

Abstract: A system and method for reducing acoustic, wind or other background noise that may interfere with sensing of a seismic signal is provided. More specifically, a shield is provided to enclose a geophone and thereby protect it from harmful noise. The shield may comprise a rigid shell, a structural damping material, an acoustically absorptive material, and a compliant seal for coupling the shield to the ground or reference surface.

Abstract: A seismic data collection unit having multiple separate geophones/geophone packages positioned in a housing wherein the geophones are offset from a vertical axis so that summing of the geophones' respective outputs minimizes certain noise in the unit's output. Specifically, the offset geophones are physically positioned or mathematically configured so as to be symmetrical about a selected vertical axis in order to cancel out certain noise in a seismic signal. The particular placement of the geophones within the housing is preferably selected so that the vertical axis around which the geophones are positioned passes through the center of gravity of the unit.

Abstract: An acoustic attenuator includes a housing having an inner side surface which defines an interior chamber and at least one dampening member both physically and acoustically coupled to the housing and projecting into the interior chamber. Acoustic energy propagating within the housing is deflected into the dampening members for acoustically dispersal within the interior chamber. In various aspects thereof, the dampening members may include one or a group of two or more generally cylindrical sleeves having one end both physically and acoustically coupled to the housing and a second end projecting into the interior chamber. Preferably, when a group of two or more cylindrical sleeves are employed, the sleeves are nested within one another. The dampening members may further include a second, oppositely disposed, group of two or more acoustic attenuators nested within one another and interdigitated with the first group of cylindrical sleeves.

Abstract: The invention provides methods and apparatus for detecting seismic waves propagating through a subterranean formation surrounding a borehole. In a first embodiment, a sensor module uses the rotation of bogey wheels to extend and retract a sensor package for selective contact and magnetic coupling to casing lining the borehole. In a second embodiment, a sensor module is magnetically coupled to the casing wall during its travel and dragged therealong while maintaining contact therewith. In a third embodiment, a sensor module is interfaced with the borehole environment to detect seismic waves using coupling through liquid in the borehole. Two or more of the above embodiments may be combined within a single sensor array to provide a resulting seismic survey combining the optimum of the outputs of each embodiment into a single data set.

Abstract: In the present invention, a seismic receiver contains an onboard digitizer that samples and converts a signal from detected seismic energy into the digital domain. The receiver contains an analog to digital converter, a transmission circuitry, and a link to the seismic detection circuitry. The signal from the seismic detection circuitry is converted into a digital signal, which is then relayed to the data recorder. These components are all resident to the receiver itself. Additional control circuitry is employed to provide clocking and testing functions. These receivers communicate with one another, and provide sampled seismic data on an individual basis. The components may be prepared on a PCB and put inside the receiver cap. The PCB may be flexible in nature, as to provide a maximum of surface mounted components in the smallest amount of space.

Abstract: A method for seismic exploration using nonlinear conversions between electromagnetic and seismic energy, with particular attention to the electromagnetic source waveform used. According to the invention, seismic returns from a source waveform are correlated with a reference waveform, with both waveforms custom designed to minimize both correlation side lobes and interference from linear electroseismic effects. A waveform element is selected which may be sequenced by a binary or similar digital code embodying the desired custom design to generate an input sweep with the needed depth penetration and noise suppression. Correlation of the seismic response with the reference waveform in a data processing step mathematically aggregates the seismic response from the input sweep into a single wavelet. Preferred binary digital codes include prescribed variations of maximal length shift-register sequences. Also, an apparatus for generating the desired waveforms.