Method of recording seismic signals to search and explore hydrocarbons in structures of underwater geological arrays

FIELD: physics.

SUBSTANCE: method for recording seismic signals to search for and explore hydrocarbons in the structures of underwater geological arrays, according to which seismic waves are recorded, including responses in water from the PS- and SS-waves reflected from inhomogeneities in the underwater geological arrays and generated by the seismic wave source, by means of receivers located in the water layer, and analyzing the temporal recordings of the signals is performed, by the results of which the investigated underwater geological arrays are judged. Herewith the receivers are positioned near the water surface and are removed from the source by a minimum predetermined distance, which makes it possible to record the responses in water from the PS- and SS-waves, which is determined by full-wave numerical modeling based on the known bottom relief data and/or thickness of the water layer, and/or the investigated underwater geological array.

EFFECT: reducing the labour intensity, technical and technological complexity of work with simultaneous increasing the informative nature of seismic studies.

3 cl, 4 dwg, 1 tbl

 



 

Same patents:

FIELD: physics.

SUBSTANCE: in seismic survey in icy water, streamers are towed behind a vessel under the water surface to avoid collision with ice. GPS readings may not be consistently obtained because the ice prevents a tail buoy with a GPS receiver from trailing from the streamer on the surface Instead, a device is towed on the streamer under the water surface. The absolute position of the streamer is tracked by intermittently bringing the towed device towards the surface so that GPS readings can be obtained. The absolute position of the streamer can then be used in conjunction with compass readings and can correlate various seismic sensor signals obtained along the streamer during the survey. The compass readings can be corrected for declination using declinometer readings, which can be compensated for iron effects from the vessel or other device carrying the declinometer.

EFFECT: high accuracy of survey data.

31 cl, 33 dwg

FIELD: physics; geophysics.

SUBSTANCE: invention relates to geophysics and can be used in seismic exploration to detect oil and gas deposits. The invention discloses a method and an apparatus for marine seismic survey using one or more movable marine seismic vibrators. The sweeping function for the vibrator is based on the criterion of allowable degradation and is a nonlinear function which performs frequency sweeping from top downwards. The obtained data can be used directly without cleaning or can be easily cleaned.

EFFECT: high accuracy of survey data.

21 cl, 11 dwg

FIELD: physics, geophysics.

SUBSTANCE: invention relates to geophysics and can be used for sea seismic works. Claimed are seismic streamer and related method of evaluation of the shape of seismic streamer controlled in transverse direction. This seismic streamer is divided into several adjacent sections of seismic streamer by control devices in transverse direction. Heading transducers arranged fore and aft of every section generate the data on heading. Every section is simulated as a rectangular fore and curved fore section. Section shape is evaluated in compliance with this model from the data on heading towards the section.

EFFECT: higher precision of trial data owing to precision of seismic streamer shape evaluation.

19 cl, 2 dwg

FIELD: physics.

SUBSTANCE: disclosed is a small-size bottom seismic module, connected by a hydroacoustic link to a control station and consisting of a sealed housing, a hydrophysical module, a device for detecting geophysical signals, which includes a bottom seismometer, information storage means, a spatial orientation sensor, a radio buoy, a ballast, a ballast release, a release timer, a flash beacon, a radio beacon, an external communication socket and a power supply. The sealed housing has the shape of a hemisphere which is linked to the base of the sealed housing which is in the form of a plate, on the upper diameter of which there are mechanical elements of the ballast release, which are in the form of straps which are linked to the ballast, tightly adjoining the base of the sealed housing on its lower diameter. The means of communicating with the control station are in the form of a single-relay hydroacoustic link. The spatial orientation sensor consists of an electronic 3D compass, three accelerometers and three angular velocity measuring devices, rigidly linked to the bottom seismometer, and the bottom seismometer is in the form of a wideband molecular-electronic sensor.

EFFECT: high reliability of detected seismic signals.

3 dwg

FIELD: physics.

SUBSTANCE: acoustic signal is emitted toward sea bottom. Signal of sound reradiation from water column is received. Gas flares are isolated from receive signal. Gas flare inclination is used to evaluate the stream velocity profile and direction. Density of gas flare sources on sea bottom and methane flow direction in water for every flare are calculated. Obtained data allows the determination of methane concentration in water column in the area of methane discharge.

EFFECT: higher efficiency and accuracy of evaluation.

1 dwg

FIELD: instrumentation.

SUBSTANCE: offered invention relates to measuring equipment and can be used for development and manufacture of oceanological multichannel information and measuring complexes and development of new measuring oceanological channels. The hydrological-optical-chemical complex contains a unit of hydrophysical measuring channels, a central controller, the first and second modems of the electric communication line, a conducting rope with electric and fibre-optical communication lines, a rotating electric transition, an electric winch, an operator workstation, a unit of optical measuring channels, and a unit of normalising controllers is added to it, and each hydrophysical measuring channel through the corresponding normalising controller is connected to the central controller, besides, the first and second multiport optical modems and the rotating optical transition are added, and each optical measuring channel is connected to the corresponding input of the first multiport optical modem connected through the fibre-optic communication line of the conducting rope to the rotating optical transition connected to the second multiport optical modem connected to the operator workstation. The information from the measuring channels of the hydrophysical module is processed by the normalising controllers, and in compact way by the central controller through the multiport modem is transferred to the onboard device of the probe, and also in creation of conditions for development, manufacture, laboratory and natural studies of new optical measuring channels for identification and registration of quantity of a mineral suspended matter and the weighed organic substance in sea water, integration of currently existing measuring oceanologic channels, creation of the combined channel of the electric and fibre-optical communication line between submersible and onboard devices.

EFFECT: integration in a single hydrological-optical-chemical complex of all available measuring channels of oceanological parameters.

1 dwg

FIELD: radio engineering, communication.

SUBSTANCE: invention relates to hydroacoustic equipment and to the creation of deployment-retrieval devices (DRD) of flexible extended trailing antennas (FETA) on submarines and on surface ships. The invention proposes a DRD structure in which the deployment of the antenna to the stream in case some part of the antenna is wound on a winch, and its other part is arranged in a tubular storage unit, is provided by the creation of excess pressure in the tubular storage unit by means of a centrifugal pump, a sealing device on the end face of the tubular storage unit, which is close to the winch, is made in the form of a cylindrical module of the same inner diameter as the tubular storage unit, which is rigidly and tightly attached to it, and the suction pipeline of the centrifugal pump is made of two branch pipes, one of which is directed outboard and the other one is tightly attached to the inner volume of the tubular storage unit with an additional conical flange coaxial to the tubular storage unit and installed near its fore end face between the conical flange connected to the pressure pipeline and the sealing device of the fore end face of the tubular storage unit, the conical flange of the pressure pipeline is oriented with its constriction to the aft part of the tubular storage unit, and the conical flange of the suction pipeline is oriented with its constriction to the fore part.

EFFECT: increasing the safety of deployment and retrieval of flexible extended trailing antennas, some part of which is wound on a winch of deployment and retrieval devices, and some part is located in the tubular storage unit, without its damages or stops.

1 dwg

FIELD: measurement equipment.

SUBSTANCE: invention relates to devices for measurement of geophysical parameters in bottom area of seas and oceans. Substance: seismic module comprises a tight body (1), inside of which there is a hard disk drive (5), a unit (7) of a hydroacoustic communication channel, a ballast (2) breaker (8), a timer (9) of the breaker (8) of ballast (2), a flashing beacon (10), a joint (11) of external communication, a source of power supply (12), a hydrophysical module (13), a radio beacon (14), a seismic sensor (15), a unit (20) of spatial orientation. Besides, the unit (20) of spatial orientation comprises an electronic 3D compass, three accelerometers and three meters of angular speeds rigidly coupled with the seismic sensor (15). The seismic detector (15) is made in the form of a wideband molecular-electronic sensor. The tight body (1) is made in the form of a hemisphere with a base in the form of a plate, along the upper diameter of which there are mechanical elements of the ballast (2) breaker (8) installed. Mechanical elements of the ballast (2) breaker (8) are made in the form of slings (3), which are coupled to ballast (2) and tightly adjoin the base of the tight body (1) along its lower diameter. The hydroacoustic communication channel for connection of the seismic module with the dispatching station is made as single-relay.

EFFECT: increased validity of recorded data.

3 dwg

FIELD: transport.

SUBSTANCE: invention relates to ship building, particularly, to surface scientific and research vessels. Scientific and research icebreaking vessel is proposed for carrying out 3D seismic technology exploration irrespectively to ice conditions which vessel has a hull where seismic equipment is located, as well as a shaft for bay cable laying. To move source of acoustic waves untethered unmanned submersible is used which bases on a vessel and is dropped and lifted via separate vertical shaft using running - pulling tool.

EFFECT: improved operational performance of scientific and research vessel for seismic exploration.

3 cl, 1 dwg

FIELD: physics; geophysics.

SUBSTANCE: invention relates to geophysics and can be used in marine seismic prospecting. Disclosed is an underwater seismic recording system for reducing noise in seismic signals caused by reflected ghost waves or movement through the water. The system comprises two motion sensors. One sensor has a first response and sensitivity to noise caused by movement of the platform, as well as to acoustic waves. The second sensor has a different structure, which insulates the sensor from acoustic waves such that the response is primarily associated with noise caused by movement. Output data of the responses of the two sensors are combined to eliminate the effect of the noise caused by movement. Upon further combination with a hydrophone signal, noise caused by reflected ghost waves is reduced.

EFFECT: high accuracy of prospecting data.

14 cl, 19 dwg

Q tomography method // 2558013

FIELD: physics; geophysics.

SUBSTANCE: invention relates to geophysics and can be used to process seismic survey data. A method for reconstructing subsurface Q models (110) from seismic data (10) by performing ray-based (60), centroid frequency shift (50) Q tomography is disclosed. The amplitude spectrum of the seismic source waveform is approximated (40) by a frequency-weighted exponential function of frequency, having two selected parameters to adjust the frequency shift data, thereby providing a better fit to various asymmetric source amplitude spectra. Box constraints may be used in the optimisation procedure, and a multi-index active-set method used in velocity tomography is a preferred technique for implementing the box constraints (100).

EFFECT: high accuracy of seismic survey data.

20 cl, 12 dwg

FIELD: physics; geophysics.

SUBSTANCE: invention relates to geophysics and can be used in processing seismic data when searching for hydrocarbon deposits. The disclosed method of identifying geologic features from geophysical or attribute data includes using windowed principal component, or independent component, or diffusion mapping analysis. Subtle features become identifiable in partial or residual data volumes. The residual data volumes are created by eliminating data not captured by the most prominent principal components. The partial data volumes are created by projecting the data onto selected principal components. Geologic features may also be identified from pattern analysis or anomaly volumes generated with a variable-scale data similarity matrix.

EFFECT: high accuracy of prediction data of oil and gas content of an investigated area.

31 cl, 11 dwg

FIELD: physics; geophysics.

SUBSTANCE: invention relates to geophysics and can be used to process seismic data. Disclosed is a method of converting seismic data to obtain a subsurface model of bulk modulus or density. The gradient of an objective function is calculated (103) using the seismic data (101) and a background subsurface medium model (102). The source and receiver illumination coefficients are calculated (104) in the background model. The seismic resolution volume is calculated (105) using the velocities of the background model. The gradient is converted (106) into the difference subsurface model parameters using the source and receiver illumination coefficients, seismic resolution volume and the background subsurface model. Said values are scalable coefficients, used to compensate seismic data after migration by reverse time migration, which can then be related to a subsurface bulk modulus model. For iterative inversion, the difference subsurface model parameters (106) are used (107) as preconditioned gradients.

EFFECT: high accuracy of obtained data.

21 cl, 7 dwg

FIELD: physics.

SUBSTANCE: method includes successive operations for acquiring and preparing data by a common-depth-point method, seismic logging, vertical seismic profiling, acoustic logging, gamma-ray density logging and verifying the quality of said data, and obtaining reference values of interval velocities; obtaining an initial hodograph and calculating a synthetic seismogram; performing quality control and inputting a constant time adjustment for landing on the upper reference horizon of the lithologic and stratigraphic system; recalculating the synthetic seismogram and performing quality control again; calculating and inputting an adjustment for landing on the lower reference horizon of the lithologic and stratigraphic system; recalculating the synthetic seismogram and performing quality control; transferring the point of the obtained hodograph to the nearest acoustically weak boundaries; recalculating the synthetic seismogram, followed by quality control and obtaining an apriori hodograph.

EFFECT: high reliability and accuracy of alignment of horizons of a time section and geologic marks of a well.

11 cl, 2 dwg

FIELD: physics.

SUBSTANCE: method for making acoustic logging measurements includes grouping received acoustic waveforms into one of a plurality of groups, each said representative group corresponding to certain measured borehole condition parameters (e.g., a range of measured deviation values and/or a range of measured azimuth angles). The acoustic waveforms stored in at least one of the groups are stacked so as to obtain an averaged waveform. The averaged waveform may be further processed, for example, via a semblance algorithm to obtain at least one acoustic wave slowness.

EFFECT: high accuracy of logging data.

17 cl, 4 dwg

FIELD: physics; geophysics.

SUBSTANCE: invention relates to geophysics and can be used to determine elastic properties or rocks based on seismic data. Disclosed is a method of determining elastic properties of rocks based on stratal adaptive inversion of seismic data, characterised by use of layered models of the environment in which minimum temporary power values τmin of strata correspond to the real seismic resolution and the sedimentation geology and are calculated using the formula: τmin(me)=141000Δf, where Δf is operating frequency band. The initial model used is an adjusted geo-acoustic model of impedances of the corresponding well, or an impedance path of seismoacoustic section on a diagonal profile. When constructing the working model, the seismic time section is converted into a detailed layered model of acoustic impedances (seismoacoustic section) from which the range of variation of acoustic parameters of the layers is determined.

EFFECT: high accuracy of evaluating elastic properties of rocks.

1 dwg

FIELD: physics; geophysics.

SUBSTANCE: invention relates to geophysics and can be used in seismic exploration. The seismic sensor module includes sensing elements arranged in a plurality of axes to detect seismic signals in a plurality of respective directions, and a processor to receive data from the sensing elements and to determine inclinations of the axes relative to a particular orientation. The determined inclinations are used to determine noise that has leaked into a seismic signal along the particular orientation due to seismic signals propagating in other orientations. The collected seismic data, taking into account the determined inclination, are rotated to transmit the signal along the target orientation without transmitting any other seismic signal in another orientation.

EFFECT: high accuracy of seismic data.

19 cl, 5 dwg

FIELD: physics; geophysics.

SUBSTANCE: invention relates to geophysics and can be used in processing seismic data. Method involves receiving seismic data acquired when surveying a region, the region being associated with locations; processing the seismic data to estimate at least one frequency dependent surface wave property within the region; determining a frequency dependent data processing geometry for each location based at least in part on the estimated frequency dependent surface wave property (properties). The method also involves processing the seismic data based at least in part on the determined data processing geometries to derive a spatially continuous representation of a surface wave property across the entire region.

EFFECT: high accuracy of survey data.

22 cl, 8 dwg

FIELD: physics.

SUBSTANCE: elastic vibrations are excited repeatedly at different inclination angles relative to the points of reception in air, water or on a solid body floating on water. The elastic vibrations are detected by sensors situated on the earth's surface, at the bottom of the water reservoir or inside an elastic half-space and stored in digital form. Further, seismograms are formed for apparent sources located at each point of reception via summation of records in each seismic detector with advancing delays equal to the time of propagation from real vibration sources to selected apparent sources, controlled based on the time of detecting the first arrival at the location of the apparent source.

EFFECT: high accuracy of exploration data by improving the signal-to-noise ratio.

6 dwg

FIELD: physics.

SUBSTANCE: pairwise continuous juxtaposition of a plurality of paths of a seismic section or cube is performed. A two-dimensional function of mutual difference of fragments of seismic records of paths is calculated for each pair of seismic section paths or each pair of paths of all in-lines and all cross-lines. Values of said function are calculated for all possible combinations of the time (depth) of said pair of paths, which may belong to one seismostratigraphic level. Functions of optimum conformity of time/depth from the i-th to the k-th seismic path ti+k=φ+k(ti) and ti=φk(ti+k) are calculated, followed by calculation of transfer functions for the time or depth domain of all neighbouring seismic paths. Said transfer functions enable to form a single continuous seismostratigraphic model, which is two-dimensional for the section and three-dimensional for the cube.

EFFECT: high accuracy of data for mapping formations and reconstructing parameters of a geologic environment.

6 dwg

FIELD: measurement equipment.

SUBSTANCE: device includes the first antenna 1, small-pressure barometer 2, the first ADC 3, the second ADC 4, the third ADC 5, the fourth ADC 6, the fifth ADC 7, personal computer (PC or a microprocessor) 8, unit of a common timing system (GPS or GLONASS) 9, subscriber coupling unit 10, the first amplifier 11, the first filter 12, the second amplifier 13, the first threshold unit 14, OR circuit 15, the second antenna 16, the third amplifier 17, the second filter 18, the fourth amplifier 19, the second threshold unit 20, the third antenna 21, the fifth amplifier 22, the third filter 23, the sixth amplifier 24, the third threshold unit 25, the seventh amplifier 26, the fourth filter 27, the eighth amplifier 28, the fifth filter 29, the fourth threshold unit 30, the first AND circuit 31, the first DAC 32, the first calibrator 33, the second DAC 34, the second calibrator 35, the third DAC 36, the third calibrator 36, the fourth DAC 37, the fourth calibrator 38, the fifth DAC 39, the first shaper 40, the sixth DAC 42, the second shaper 43, the first timer 44, the second AND circuit 45, the first counter 46, clock generator 47, the second timer 48, the first quad unit 49, adder 50, divider 51, the fifth threshold unit 52, the third AND circuit 53, the third timer 54, the fourth AND circuit 55, the second counter 56, the second quad unit 57, and the third quad unit 58.

EFFECT: possible use of a device at short distances in real time and increase of interference immunity of the device at available interfering signals.

1 dwg

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