1108 results about "Geophone" patented technology

In one embodiment the invention comprises a particle velocity sensor that includes a housing with a geophone mounted in the housing. A fluid that substantially surrounds the geophone is included within the housing. The particle velocity sensor has an acoustic impedance within the range of about 750,000 Newton seconds per cubic meter (Ns/m<3>) to about 3,000,000 Newton seconds per cubic meter (Ns/m<3>). In another embodiment the invention comprises method of geophysical exploration in which a seismic signal is generated in a body of water and detected with a plurality of co-located particle velocity sensors and pressure gradient sensors positioned within a seismic cable. The output signal of either or both of the particle velocity sensors or the pressure gradient sensors is modified to substantially equalize the output signals from the particle velocity sensors and the pressure gradient sensors. The output signals from particle velocity sensors and pressure gradient sensors are then combined.

A portable self-standing electromagnetic (EM) field sensing locator system with attachments for finding and mapping buried objects such as utilities and with intuitive graphical user interface (GUI) displays. Accessories include a ground penetrating radar (GPR) system with a rotating Tx/Rx antenna assembly, a leak detection system, a multi-probe voltage mapping system, a man-portable laser-range finder system with embedded dipole beacon and other detachable accessory sensor systems are accepted for attachment to the locator system for simultaneous operation in cooperation with the basic locator system. The integration of the locator system with one or more additional devices, such as fault-finding, geophones and conductance sensors, facilitates the rapid detection and localization of many different types of buried objects.

A method and apparatus is disclosed for performing a seismic survey below the surface of a body of water and on the seabed. In one embodiment, a plurality of seismic data receivers are removably loaded in a carrier located above the surface of the water and the carrier is lowered into the water and placed at a depth relatively close to the seabed. Each of the receivers has a memory for recording the vibrations of the seabed and has a switch for activating the memory. A ROV is used to unload the receivers from the carrier and to deposit each receiver on the seabed and along a survey line. In one embodiment, the receivers comprise a frame, a pressure vessel for housing the memory and remotely activated controls, and a geophone that is separately planted into the seabed at a relatively short distance from the frame.

This invention discloses a valve that generates a hydraulic negative pressure pulse and a frequency modulator for the creation of a powerful, broadband swept impulse seismic signal at the drill bit during drilling operations. The signal can be received at monitoring points on the surface or underground locations using geophones. The time required for the seismic signal to travel from the source to the receiver directly and via reflections is used to calculate seismic velocity and other formation properties near the source and between the source and receiver. This information can be used for vertical seismic profiling of formations drilled, to check the location of the bit, or to detect the presence of abnormal pore pressure ahead of the bit. The hydraulic negative pressure pulse can also be used to enhance drilling and production of wells.

A method and device for seismic exploration of a subsea geologic formation by pickups set on the sea bottom and intermittently connectable to active data acquisition stations (11) brought nearby. Permanent passive reception stations (1) comprising a heavy pedestal provided with housings for seismic pickups (geophones (6), hydrophone (7)) which receive acoustic or seismic signals from the underlying formation are arranged at the bottom of the water body. When collection sessions for the signals received by the pickups are scheduled, mobile active acquisition stations (11) connected to permanent passive reception stations (1) are positioned at the bottom of the water body. The signals picked up are then recorded, for the time required to carry out at least one session of acquisition and recording of the acoustic or seismic signals received by the passive stations in response to the emission of seismic waves by one or more seismic sources. The mobile active acquisition stations (11) are thereafter recovered at the surface and the records acquired by each one are transferred to a central collection laboratory.

A method is disclosed for processing seismic data from concurrently recorded co-located pressure sensors and geophones. The seismic data are processed by first determining an upgoing wavefield and a downgoing wavefield in the seismic data. Adaptive subtraction is then applied to at least one of the upgoing wavefield and the downgoing wavefield to remove the noise from the signal. In alternative embodiments, the upgoing wavefield can be used as a noise model for the downgoing wavefield or the downgoing wavefield can be used as a noise model for the upgoing wavefield.

A method is disclosed for combining seismic data sets. This method has application in merging data sets of different vintages, merging data sets collected using different acquisition technologies, and merging data sets acquired using different types of sensors, for example merging hydrophone and geophone measurements in ocean bottom seismic data. In one embodiment, a desired data trace is to be determined from a set of measured data traces, and the following steps are applied: (a) model filters are constructed which express the deterministic relationship between the desired data trace and each available measured trace that depends on the desired data trace; (b) the noise properties associated with each measured data trace are determined; (c) a sufficient statistic for the desired data trace is formed by application of an appropriate filter to each measured trace and summing the filter outputs; (d) the sufficient statistic is further processed by a single-input single-output estimator to construct an estimate of the desired data trace from the sufficient statistic.

A seismic exploration method and unit comprised of continuous recording, self-contained wireless seismometer units or pods. The self-contained unit may include a tilt meter, a compass and a mechanically gimbaled clock platform. Upon retrieval, seismic data recorded by the unit can be extracted and the unit can be charged, tested, re-synchronized, and operation can be re-initiated without the need to open the unit's case. The unit may include an additional geophone to mechanically vibrate the unit to gauge the degree of coupling between the unit and the earth. The unit may correct seismic data for the effects of crystal aging arising from the clock. Deployment location of the unit may be determined tracking linear and angular acceleration from an initial position. The unit may utilize multiple geophones angularly oriented to one another in order to redundantly measure seismic activity in a particular plane.

The invention relates to a near-surface modeling method using tomography inversion of a two-step method. The near-surface modeling method specifically comprises the following steps of: (1) picking and inputting short-refraction first-break; (2) carrying out tomography inversion on the short-refraction first-break and outputting explanation results capable of reflecting fine velocity change in an extremely shallow stratum as shown in picture 2; (3) picking a big shot and recording first-break time; (4) interpolating short-refraction inversion results in combination with explanation results of a microlog in a work area by using a kriging method and building near-surface velocity body of the extremely shadow stratum; (5) meshing and constraining inversion initial-velocity modeling, replacing a near-surface velocity body at the extremely shallow stratum obtained in the last step into the shallow stratum part of the initial model generated at the big-shot first-break, replenishing the velocity loss of the extremely shallow stratum resulting from the excessive minimum offset distance of the big shot; (6) constraining generation of a weight field; and (7) inversing the near-surface velocity model by using a constrained chromatography method, picking the top interface of a high-speed layer on the basis of a velocity-depth model obtained by tomography inversion, and calculating static correcting values of a shot point and a geophone position.

An apparatus and method are disclosed for imaging a diffraction grating with a very high depth of focus, using a highly accurate code plate position measurement system. Positions may be measured to an accuracy of 1 nm or even smaller. The system may be used in fields such as manufacturing integrated circuits, and low- and very-low-frequency geophones, and other low- and very-low-frequency acoustic detectors.

The invention belongs to seismic data processing in petroleum geophysical exploration and geological engineering survey, and relates to near-surface velocity modeling and static correction in seismic exploration aiming at research and development of a shallow velocity model required for combined post static correction in a detector chamber of single-point high-density seism. A method for establishing a near-surface velocity model in high-density seismic static correction processing comprises the following steps of: supposing that the near-surface velocity is linearly increased along with the depth, calculating refracted wave velocity of different geophone offset from the travel time difference of primary waves of adjacent detection points of the high-density seism according to the physical property of the primary wave of the near-surface velocity field, establishing a near-surface ramp velocity field parameter according to the relationship between the geophone offset and the refracted wave, and further establishing the near-surface velocity model which can be directly used for static correction quantity calculation in seismic processing and also can be used as an initial model for tomographic inversion of near-surface velocity. The method has high calculation speed, and does not depend on the change of the initial position caused by a seismic focus.

A method and system for acquiring seismic data while conducting drill string operations in a wellbore. The seismic receiver combination set comprises a combination of orthogonal geophones and accelerometers, and an array of hydrophones.

Provided are a method and a device for tunnel advance geology forecast with tunnel face blasting as a focus. The method comprises the steps of (1) drilling holes on two lateral walls at the inlet position in a tunnel; (2) filling a coupling agent into the drilled holes, and attaching weave detectors to the walls of the drilled holes; (3) winding a trigger circuit copper wire on cartridged explosive, and placing the cartridged explosive into a blasted hole of the tunnel face; (4), enabling two three-component weave detectors buried in a tunnel hole to receive reflective earthquake wave signals; (5) sending the signals to an amplifier after the signals are selected by a multi-way switch; (6) enabling the amplifier to amplify the signals and then transmit the signals to an analog/digital (A/D) converter through wireless transmission; (7) enabling a wireless communication module of a control chamber to receive a wireless signal and then transmit the wireless signal to a host, and recording the signal; and (8) achieving geology forecast through an processing program installed in the host. The device comprises signal acquisition, wireless communication and control and a data analyzing system. The method is simple, easy and low in cost, can be used for advance geology forecast of tunnels, holes and roadway underground spaces, and achieves automation and normalization of geology forecast.

The invention relates to a method for determining anisotropic parameters by utilizing the data of a three-dimensional VSP (Vertical Seismic Profile). The method comprises the following steps: when collecting the actual journey of the three-dimensional VSP, computing the time difference of each depth point; computing the anisotropic parameters of a VT I medium and the residual time difference after being corrected; determining the anisotropic parameters of an HT I medium according to the relation fitting between the residual time difference and the azimuth angle; computing the VT I anisotropic parameters of each depth point and the anisotropic parameters of the HT I medium point by point; obtaining the parameter curve of the relation that the anisotropic parameters are changed along with the depth; and eliminating the influence of the dynamic correction time difference which is changed along with the wellhead distance or the shot-geophone distance. In the method provided by the invention, the problem that the VT I anisotropic medium and the HT I anisotropic medium have the mutual interference is solved; the anisotropic influence of earthquake can be effectively eliminated; and the imaging quality of the earthquake and the prediction accuracy rate of oil gas are enhanced.

A seismic streamer includes a sensor comprises an axially oriented body including a plurality of axially oriented channels arranged in opposing pairs; a plurality of hydrophones arranged in opposing pairs in the channels; a pair of orthogonally oriented acoustic particle motion sensors; and a tilt sensor adjacent or associated with the particle motion sensors. The streamer has a plurality of hydrophones, as previously described, aligned with a plurality of accelerometers which detect movement of the streamer in the horizontal and vertical directions, all coupled with a tilt sensor, so that the marine seismic system can detect whether a detected seismic signal is a reflection from a geologic structure beneath the streamer or a downward traveling reflection from the air/seawater interface.