553 results about "Shot point" patented technology

Method for interpolating aliased seismic data to generate shot records at regular shot points. The method involves sorting the data into common offsets to obtain the finer sampling in the common-offset domain, then using DMO to transform the data to zero offset to eliminate azimuth and offset variations, from which densely sampled shot records are reconstructed by an efficient Log-Stretch Inverse Shot Record DMO. The method has ready application to techniques that benefit from input data that are regularly and densely sampled, such as 3-D surface related multiple elimination and shot record wave equation migration.

The invention relates to a direct prestack time migration method for the seismic data acquired under the undulant ground surface. The method is applied to reflection seismic data processing during earthquake exploration and is a prestack migration imaging method aiming at the seismic data acquired under the undulant ground surface. The method can be directly applied to the seismic data which is acquired under the undulant ground surface and is acquired at shot points and demodulation points of different heights. Accordingly, the method can avoid errors caused by field static correction processing as well as correct the speed of a speed reducing belt in a migration process. The method can self-adaptively determine time-varying migration aperture and can correctly compensate geometric spreading effect of seismic waves during an imaging process so as to obtain an amplitude-preserved common reflection point gather. The core of the method is to use a one-way wave theory and a stable phase point principle to analyze so that the travel time and the amplitude of the seismic waves, which depend on the speed and thickness of the speed reducing belt, the heights of the shot points and the demodulation points, and stacking speed based on a floating datum plane, are obtained. The method has important application value for the explorations of oil, gas and mineral resources in areas with complex ground surfaces.

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.

The invention provides an underground engineering construction advanced geological prediction system and a prediction method thereof which comprise earthquake wave receivers that are distributed in the underground construction tunnels and the arrangement method thereof, an earthquake wave collector and an earthquake wave data processing and analyzing system, wherein, the earthquake wave collector is formed by connecting a system motherboard and 16 collecting daughter boards in a way of inserting card, and the daughter boards are communicated with the system motherboard by connecting sockets to obtain electricity; the system motherboard comprises an SCM master-control circuit, a power, a power light, a serial port, a USB port and a wireless port; each collecting daughter board comprises a connecting socket used for connecting with the motherboard, and a field programmable gate array circuit FPGA; the earthquake receiver is a multi-component spatial receiver, which comprises a detector and a supporting carrier for the detector; the earthquake wave data processing and analyzing system is a computer in which an earthquake wave data processing and analyzing software is installed. The system can detect the shape of spatial 3D geologic body, improves the reliability and accuracy of construction advanced geological prediction, is used for underground engineering construction advanced geological prediction and applicable for various underground engineering excavations, furthermore, shot points and receivers of this system can be flexibly arranged.

The invention provides a seismic anisotropy parameter full waveform inversion method and device, and belongs to the field of seismic anisotropy parameter prediction in oil geophysical exploration. The method comprises the steps that (1) seismic data which are going to carry out anisotropy parameter inversion are acquired, namely observation wave field data; (2) denoising processing is carried out on the seismic data acquired in the step (1) to acquire denoised data; (3) by using the denoised data acquired in the step (2), and according to shot point and receiver point coordinates, a common midpoint gather is extracted to acquire seismic CMP gather information, and then the seismic CMP gather information is used to calculate the interval velocity of a horizontal stratum; (4) by using the interval velocity, which is acquired in the step (3), of the horizontal stratum, an initial model used for inversion is constructed in an interpolation mode; and (5) small perturbation is carried out on each parameter of the initial model to generate a model after parameter perturbation.

A shorter spatial wavelength static correction method for exploration seismic data using first arrivals according to the invention includes the steps of: based on a quadratic curve fitting to the first arrivals, which are picked up from seismic wave records of receiver gathers after the field statics, obtaining the difference DELTAi,j between the observed first arrival time tij of the receiver point j with respect to the shot point i and the corresponding time value of the fitted quadratic curve; and forming the original matrix DELTA having mxn elements DELTAi,j, where n is the total number of shot points and m is the total number of receiver points of the line; substituting the elements of each row by the difference between the value of each element and the row average; and substituting the elements of each column by the difference between the value of each element and the column average; repeating the iteration until less than a predetermined error; the sum of the averages of the ith row for all iterations and the sum of the averages of the ith column for all iterations are the static correction value at the ith shot point and the static at the jth receiver point respectively. Said method is applicable to 3-D seismic survey by mean of using a formula of rij={square root}{square root over (DELTAxij2+DELTAyij2)} to transform 3-D seismic data into 2-D data, so that the 3-D seismic data processing is as simple as that of 2-D data.

Methods and apparatuses for processing seismic data carrying information about a subsurface structure are provided. One method includes splitting the seismic data in groups, each group including subsets of seismic data for which a distance from a respective shot point to a receiver line in a patch of active detectors corresponding to the shot point is within a predetermined range for the group, and extracting signal data for each block Hankel matrix based on an SVD analysis thereof. Another method includes extracting signal data by subtracting from seismic data an estimated noise model obtained by rank reduction of a Hankel matrix followed by dip filtering, enhanced based on a least square matching filter with the seismic data.

The invention relates to a diffracted wave imaging method and a diffracted wave imaging device based on dynamical features. The diffracted wave imaging method comprises the following steps of acquiring a reflected wave inclination field according to earthquake imaging data; optionally taking an imaging point and recording travel time information of a ray from a shot point to the imaging point and the information of incident angle of the imaging point; acquiring travel time information of a ground surface emergent ray corresponding to an emergent angle; setting an intersection point of the emergent ray and the ground as an initial stationary phase point; recording travel time information from the imaging point to various ground surface observation points; summing the travel time information and the travel time information of the ray from the shot point to the imaging point so as to obtain travel information of a diffraction ray; taking out an amplitude numerical value of corresponding time in various earthquake records and determining an actual stationary phase point; establishing a diffracted wave amplitude coefficient curvilinear equation; acquiring an amplitude attenuation value of a diffraction ray according to the travel time information of the diffraction ray, the travel time information of the emergent angle corresponding to the ground surface emergent ray and the actual stationary phase point; and performing summing after weighting the amplitude attenuation value of the diffraction ray and a corresponding ground amplitude numerical value so as to obtain imaging results of various corresponding imaging points in an underground imaging space range.

A method for multipath imaging of three-dimensional volumes of seismic data, given the subsurface velocity distribution. Ray tracing is used to generate the volumes of information needed for migration, but using coarse-scaled grids for computational efficiency. Interpolation methods are disclosed that address the specific shot points and receiver locations and that enable a final image on a grid with the desired resolution. Data storage and retrieval techniques are also disclosed.

The invention relates to a coal roadway fault advanced-detection method based on reflecting channel wave signals. The coal roadway fault advanced-detection method includes arranging receiver points and shot points of 1 #, 2 #, 3 #, 4 #, 5 # and 6 # at the head-on front of the coal roadway sequentially, determining direct waves of 1 # to 6 # receiver points and fault reflecting channel wave seismic signal areas, finding out corresponding time of searching for a maximum amplitude value in 1 # to 6 # receiver point reflecting channel wave trains, drawing six arcs adopting the receiver points as centers, and acquiring the head-on front fault position as horizontal space among the intersecting positions of the six arcs and the head-on position. Reflecting channel wave kinematics characteristic information is used for advanced forecast, operation is easy, cost is low, subsequent processing problems are few, detection results can be acquired rapidly, detection efficiency is high, the results are accurate, and good guiding affection on safe on-site tunneling is realized.

The invention relates to an anisotropic reverse time migration method for a quasi-P wave equation in a transverse isotropy with a vertical axis of symmetry (VTI) medium. The method comprises the following steps of: (1) performing discrete differentiation on a first-order quasi-P wave equation in a two-dimensional VTI medium and a perfect matched layer (PML) absorption layer boundary equation by adopting staggered meshes to obtain high-order difference formats of forward continuation and reverse continuation of the two equations; (2) performing numeric calculation to obtain a forwards-continued wave field of a shot point and a reverse time continued wave field of a receiver point, and performing normalized correlation operation on the two wave fields to obtain a migration imaging result of each imaging point in a model; and (3) extracting common imaging point gathers from migration results to obtain a final migration profile. By the method, a problem about the migration imaging of intensive transverse speed variation and a high dip angle stratum can be solved; and the influence of anisotropy of the medium is also taken into account, and the good imaging effect of longitudinal wave data acquired from an anisotropic region can be achieved by an anisotropy-theory-based migration method.

The invention relates to a method for generating a transverse wave seismic cross section by using longitudinal wave source multi-component seismic data in petroleum seismic exploration. The method comprises the following steps: acquiring three-component seismic data by adopting multiple coverings; exciting the transverse wave and receiving the transverse wave in a well; acquiring transverse wave field static correction value and the rest static correcting value for performing transverse speed analysis; determining muting parameters, deconvolution parameters and wave filtering parameters according to wave field characteristics actually acquired and recorded, and finishing the prior pre-stack processing; and selecting stack and post-stack migration or pre-stack migration according to the complexity of the structure and a speed field for generating the cross section. The method directly utilizes data acquired by a longitudinal wave source excited three-component detector to extract the whole process reflection transverse wave for imaging, does not need special transverse wave acquisition, utilizes the transverse wave speed dynamic correction to solve transverse wave rest static correction value at a shot point, and iterates the transverse wave rest static correction value with the speed analyzing process, thereby obtaining a transverse wave imaging cross section with high static correction precision, as well as the speed field corresponding to the cross section and other parameters.

The invention relates to a processing technology of petroleum geophysical exploration data, which is a rapid and effective self-adapting ground surface consistency deconvolution method of a controllable earthquake source. The concrete steps are as follows: using a conventional controllable earthquake source to vitalize and record seismic wave data; adopting the earthquake record of the controllable earthquake source and performing absorption analysis at a selected time window to obtain an amplitude spectrum of a shot point or a demodulation point at a Q absorption model channel in a t1-t2 time window; performing Fourier transform to a scanning signal of a cannon to obtain the amplitude spectrum of scanning related wavelets; working out the exploration factor h(t); and obtaining an imaging section which has an obvious improvement in waveforms of a shallow layer, a middle layer and a deep layer and is vitalized by the controllable earthquake source and an explosive source. The invention can improve the resolving capability and realize phase switching, has the self-adapting capacity of ground surface consistency counting and can obviously improve a controllable earthquake source first-motion wave having larger near ground surface absorption influence to ensure that the processing quality of earthquake data is obviously improved.

The invention relates to a multi-seismic resource parallel motivation collecting and hybrid seismic record separating method. All measuring line shot points in an exploration area are divided into multiple corresponding sets, different scan signals are adopted by different seismic sources, motivation signals of all seismic sources are designed based on a pseudo-random method, wave detectors cover the receiving arrays corresponding to all the shot points, the wave detectors are distributed in a one-off mode, and roller paths are not needed. In the construction process, a seismograph continuously records the motivation signals to generate hybrid seismic records, after collection is completed, the hybrid seismic records of all the shot points are cut out according to the motivation times of all the shot points, and the seismic source scan signals adopted by all the shot points are used as reference signals for cross-correlation detection, namely the seismic records of each single seismic source of each shot point can be separated. Compared with an existing single-seismic-source motivation collecting method, the seismic exploration efficiency is substantially improved, n seismic sources are adopted to work in parallel, the actual construction time is 1/n of the time of the existing single-seismic-source motivation collecting method, production efficiency is improved by n times, construction cost is lowered, and a low-cost data collection method is provided.

The invention provides a Gauss beam prestack depth migration method and device. The Gauss beam prestack depth migration method includes the steps that (1), collected seismic wave data are processed to generate time domain shot gather seismic record data and determine a speed interface; (2), a depth domain speed structural model and a speed grid model are built; (3), ray tracing is carried out on the time domain shot gather seismic record data according to the depth domain speed structural model, the speed grid model and the speed interface, and a shot point Gauss beam and a receiver point Gauss beam are generated; (4), the total complex value travel time is determined according to the shot point Gauss beam and the receiver point Gauss beam; (5), saddle points of the total complex value travel time are scanned, and the maximum energy Gauss beam is determined; (6), accumulated imaging is carried out according to the determined Gauss beam with the maximum energy contribution to generate a migration result. The ray tracing in the migration method is carried out by means of the speed grid model and the speed structural model at the same time, so that the accuracy of the ray tracing is improved, and the imaging quality is improved.

The invention relates to the technical field of weather modification, and discloses an artificial hail-prevention operation commanding method based on a dual-polarization weather radar. The method comprises the following steps: 1, carrying out the data recording and preprocessing; 2, carrying out the data quality control; 3, recognizing the phase of hydrometeor through employing a fuzzy logic element method; 4, judging a strategy; 5, formulating and publishing the hail prevention operation information. The method employs the fuzzy logic element method for the recognition of the phase of the hydrometeor, gives out an optimal moment for artificial hail prevention according to a discrimination strategy, and converts the information into accurate information for the weather modification operation through combining with a shot point. Meanwhile, the sound-light alarm is given in needs, thereby preventing the working moment from being missed. A hail-prevention operation commanding method is formed based on the X-band dual-polarization radar, and is enabled to carry out the business operation. The system is simple and convenient to operate, is visual and efficient, and greatly improves the artificial hail-prevention operation commanding capability and effect.

The invention relates to a seismic prospecting method based on a single seismic focus directional lighting. An offset distance and a track pitch are determined according to the traditional geologic prospecting method; a wave-detector array is arranged in a collinear way; according to the different offset distance of the shot-points in the same group and the same offset distance of the m shot-points in the different groups with the serial number differing in n, seismic data in a single shot on an entire cross-section is gathered; a uniformly-spaced time delay is made for the seismic data in the single-shot in the same group according to the sequence of the serial number; a linear superposition is made for the delayed seismic data in the single-shot so as to compose a directional lighting seismic signal with directivity, and the directional lighting seismic signal is corresponding to a directional seismic wave field; by adopting a routine seismic data processing method, a directional lighting seismic cross-section based on the single seismic focus can be obtained. After a test, the direction of the directional lighting seismic wave field that is composed can be controlled manually according to a target occurrence and has better prospecting effect to the target body of a steep dip, as compared with the common seismic prospecting method based on the single seismic focus; the seismic prospecting method of the invention also has the advantages of low operation cost and simple operation as compared with a phased seismic prospecting method.

The invention provides a near-surface speed modeling method and device. The method comprises the following steps: acquiring working area micro-logging data and explaining an acquired result to obtain micro-logging lithological layering data and a speed explaining result; adopting a non-seismic exploration method to carry out surface layer structure investigation on a working area to obtain a surface layer structure explaining profile map; according to the surface layer structure explaining profile map, the micro-logging lithological layering data and the speed explaining result, determining a mathematic relation between the speed of each stratum or each lithological layer and a non-seismic physical geography property; determining a near-surface speed of each measured point in the non-seismic exploration method according to the mathematic relation between the speed of each stratum or each lithological layer and the non-seismic physical geography property; and carrying out interpolation by using the near-surface speed of each measured point in the non-seismic exploration method to obtain near-surface speed data of each seismic shot point and each wave detection point. By the aid of the near-surface speed modeling method and device, the near-surface speed model precision is improved, and the static correction effect of processing seismic data is easy to improve.

The invention discloses a method for determining effective excitation points on the basis of illumination energy of target strata during geophysical prospecting for petroleum. The method includes designing an observation system for the target strata; performing forward modeling on the observation system after shots are infilled in the observation system; acquiring illumination energy generated by each shot for each surface element on the target strata; determining positions of the surface elements with the minimum energy; computing illumination energy of each shot in a standby shot point set for areas with the minimum energy according to average value and distance energy ratios; determining the effective excitation points to select infill shot points according to average variance of the illumination energy of shots in a shot set for the target strata. Shot points selected from the standby shot point set are added into an effective excitation point set to form the shot set. The method has the advantages that the observation system can be effectively arranged in areas with high steep structures, overthrust nappe structures and structures with violent speed horizontal change, the illumination intensity of shadow areas can be improved by the minimum effective excitation points, and the quality of seismic sections can be improved.

The invention relates to geophysical exploration, in particular to a prestack migration technology of a two-dimensional Gaussian ray bundle. The technology comprises the following steps of: performing integral transformation on track data and Hilbert transformation data obtained by processing seismic data of each track in a shot gather to obtain a discrete template table; calculating the shot point ray path and travel time of a given shot point ray angle; calculating the Gaussian ray bundle kinetic parameter of the shot point according to the travel time by using a Gaussian ray bundle kineticequation; tracking a ray according to a time interval by using the kinetic equation; calculating the ray path, travel time and a Gaussian ray bundle kinetic parameter of a demodulator probe; and laminating a migration result and displaying a stratum section image. By adopting the technology, migration is performed by the Gaussian ray bundle instead of a Kirchhoff ray, so that the problems of blind area, caustic region and multi-value travel time of the ray are solved, an imaging effect is enhanced, and the advantages of flexibility and high efficiency of a ray method are kept simultaneously.

The invention discloses a method and an apparatus for determining a poynting vector of a seismic wave field and a computer storage medium. The method comprises the following steps: establishing an underground shot point forward-propagation wave field and a detection point back-propagation wave field; determining a medium type of the forward-propagation wave field and the back-propagation wave field; when the media are isotropic media, performing vertical-horizontal wave field separation on the forward-propagation wave field and the back-propagation wave field according to a preset equation decoupling algorithm, and when the media are heterogeneous anisotropic media, performing longitudinal-horizontal wave field separation on the forward-propagation wave field and/or back-propagation wave field according to a preset variation function IDW interpolation algorithm; decomposing a separated longitudinal-wave wave field and/or a transverse-wave wave field in a top direction, a bottom direction, a left direction and a right direction, and obtaining multiple directional-wave wave fields; and selecting multiple directional-wave wave fields from the multiple directional-wave wave fields, and calculating the poynting vector of the multiple directional-wave wave fields. By adopting the method, the poynting vector of each decomposed directional wave field can be calculated, so that more accurate angle-domain imaging gather can be obtained, and the imaging quality can be improved.

The invention discloses ellipse expansion imaging method and device of seismic data processing under the condition of a true ground surface, belonging to the technical field of reflection seismic data processing in seismic exploration. The method comprises the following steps of calculating a position coordinate of a reflection point and a position coordinate of an exposure point of a normal line of the reflection point on an offset line according to a position coordinate of a shot point, a position coordinate of a receiver point, a position coordinate of a virtual image point and a position coordinate of a preset imaging position point; calculating a position coordinate of the corrected shot point and a position coordinate of the corrected receiver point according to a preset datum plane, a linear equation of the offset line and a position coordinate of the preset imaging position point; calculating travelling times between the shot point and a corrected shot point, the receiver point and the corrected receiver point as well as the exposure point and the preset imaging position point according to speeds of media of the position coordinate of the shot point, the position coordinate of the receiver point, the position coordinate of the exposure point, the position coordinate of the corrected shot point, the position coordinate of the corrected receiver point, the preset imaging position point and the preset datum plane, and obtaining a zero-offset time section by carrying out ellipse expansion tangental interference and superposition according to the travelling times.