177 results about "Geophysical prospection" patented technology

The invention discloses a method for obtaining an underground three-dimensional density structure, relates to the field of geophysical prospection, and solves the technical problem that the underground three-dimensional density structure cannot be accurately obtained in the prior art. The method is characterized by comprising the following steps: determining the vertical coordinates, horizontal coordinates, depth, and 2D (two-dimensional) profile interval of a modeling area; carrying out gravity inversion modeling by adopting a Naive Bayesian classification method according to prior information and the modeling area, so as to obtain an initial geological model; constructing the initial geological model into a 2D geological model by adopting a discrete body simulation method; splicing and fitting the 2D geological model into a 3D geological model; performing visualization and structure interpretation treatment on the 3D geological model, so as to obtain the underground three-dimensional density structure . The method is mainly based on the Bayesian classification inversion principle, and is combined with the discrete body simulation technology, so as to realize accurate establishment of a weight density mode, and improve the accuracy of the obtained underground three-dimensional density structure.

The invention relates to a laser ultrasonic detection system and a detection method thereof. The system is used for generating and receiving field seismic exploration seismic waves simulated by an ultrasonic method under the indoor condition. A complete set of laser ultrasonic automatic acquisition system comprises a set of intense pulse laser source, a single-point laser Doppler seismograph, a three-dimensional laser Doppler seismograph, a 24-bit analog-to-digital converter, a three-dimensional coordinatograph and the like. The system solves the problems of a large number of conventional geologic model simulation methods, can perform single-point and three-component non-contact ultrasonic detection, and meets the requirement of modern geophysical exploration on fine and multi-component simulation.

The invention relates to an iteration acquisition method for a first arrival wave processed by petroleum geophysical prospection data. The method comprises the following steps of: calculating an energy ratio at each sampling point to acquire an energy ratio curve; determining a first arrival prediction value; finding the maximum amplitude value by using the first arrival prediction value as a starting point; calculating an absolute value and an average value of a time difference of adjacent first arrivals; calculating a reliability coefficient in an arrangement way by using time of one first arrival and time of a front first arrival and a rear first arrival; and performing Lagrange polynomial fitting interpolation on a first arrival with the reliability coefficient of 0 by using front and rear adjacent four reliable first arrivals to acquire a first arrival prediction value. By the method, first arrival time in complicated areas influenced by larger variation of a first arrival wave shape, mutual interference of various waves, external interference and the like can be acquired accurately, and the problem of a first arrival acquisition method is solved.

The invention provides a phase-controlled earthquake inversion method in geophysical exploration, and belongs to the field of petroleum geophysical prospection. The method comprises the following steps: obtaining a three-dimensional surge impedance data volume step from inversion of original earthquake data; conducting phase control on the earthquake inversion step. The method utilizes earthquake data and a logging surge impedance curve to conduct inversion to obtain surge impedance data of a reservoir stratum under the control of result of an earthquake phase and a geologic phase, can maintain horizontal resolution while improving vertical resolution, and can finely depict space spreading and distributing form of the reservoir stratum.

The invention belongs to the technical field of geophysical exploration and discloses an ultrasonic quick scanning exploration method and a system for the same. The method comprises the following steps of: firstly, performing ultrasonic data transmission and reception by utilizing a roller scanning probe (1), and completion automatic recording of different measurement point distances according to a rolling condition; secondly, setting corresponding acquiring technical parameters by an ultrasonic data acquisition controlling and processing system (3) through a data acquisition system, and completing a synchronous acquisition task on data by an ultrasonic data acquisition device (2), thereby obtaining ultrasonic quick continuous scanning data of a measuring line point; and finally, calculating and processing the ultrasonic quick scanning data by the ultrasonic data acquisition controlling and processing system (3), explaining a detection medium according to a test profile result, and determining the abnormal position of the medium in the profile and characteristics thereof. The invention also discloses a system for the ultrasonic quick scanning exploration method. The method improves the field working efficiency of ultrasonic data acquisition.

The invention relates to a tunnel construction advanced geological detection system and method. Through the induced polarization geophysical exploration method, advanced prediction and identificationof fault fractured zones and karst caves in front of a tunnel face including water-conducting structures are performed, through setting multiple sets of detection electrodes, the position of the water-containing structure can be further determined when the water-containing structure exists in front of the tunnel face, the important reference is provided for advanced geological prediction in the tunnel construction process, and tunnel construction safety is guaranteed.

An application of three-dimensional imaging to the field of practical engineering such as nondestructive inspection, medical imaging, ground surface detection, geophysical exploration and the like is of great potential. As approximate treatment is adopted in a linear imaging algorithm, a reconstructed image is limited in precision and accuracy; and while in a non-linear algorithm such as a contrast source inversion (CSI) algorithm, position, shape and material parameters of an image such as an interested target can be gradually improved in an iteration process, and an image most similar to the interested target is reconstructed at last. The invention discloses a nonlinear imaging method for multi-frequency multi-transceiver three-dimensional electromagnetic actual measurement data based on the contrast source inversion algorithm combining a frequency hopping method with a regularization method. As forward calculation is not needed, a calculation amount for calculating a three-dimensional dyadic green function operator and a conjugate operator of the function operator in the iteration process is controllable, and a reconstruction result proves that the method can be widely applied to the field of practical applications with requirements of high-precision and high-resolution imaging due to precision and feasibility of an application to three-dimensional electromagnetic imaging.

The invention relates to the technical field of transient electromagnetic signal processing in geophysical exploration, and discloses a transient electromagnetic signal-to-noise separation method based on a variational mode decomposition principle, which is suitable for electromagnetic data filtering in a time domain. The method comprises the following steps: decomposing noisy transient electromagnetic data s(t) into K intrinsic mode functions uk(t); performing Hilbert transform on each intrinsic mode function to obtain a unilateral frequency spectrum; demodulating the frequency spectrum of each intrinsic mode function uk(t) to a corresponding base band according to the unilateral frequency spectrum, calculating a demodulated L2 norm, and calculating the bandwidth of the decomposed intrinsic mode function to obtain a constraint variation model; introducing a secondary penalty factor alpha and a Lagrange multiplication operator lambda, and converting the constraint variation model intoa non-constraint variation form; and calculating an optimal solution in a non-constraint variation form to obtain a series of optimized intrinsic mode components after VMD decomposition. The method solves the problem that transient electromagnetic data collected in geological interpretation is interfered by noise, is simple and convenient, has excellent noise separation and amplitude maintaining performance, can extract noise images, and provides conditions for subsequent noise analysis.

The invention is a seismic acquisition vibroseis pseudo random scanning signal generating method in geophysical exploration. The method comprises the following steps: a Gold sequence code is generated according to the length of to-be-generated Num groups of vibroseis pseudo random scanning signals to obtain a target amplitude spectrum; windowing processing is performed on cross-correlation and autocorrelation of the Num groups of amplitude spectrum shaping signals in a time domain to obtain Num groups of pressed reconstruction signals; the maximum value of cross-correlation between each Num group of high-cut filter signals on the same time point position is divided by the minimum value of autocorrelation of each group of signals at the time zero to obtain the maximum relative cross-correlation value of the Num groups of high-cut filter signals; and iterative modification is performed to generate the final Num groups of vibroseis pseudo random scanning signals. The method of the invention enables the cross-correlation effect between the groups of pseudo random signals to be weak, thereby inhibiting adjacent gun interference in the efficient acquisition process, and improving the separation quality of shot records. The instantaneous frequency energy does not vary monotonically with time, which can greatly reduce the risk of resonance of surrounding buildings in the vibroseis construction process.

The invention belongs to the field of geophysical exploration, and particularly relates to a ground-air short-offset electromagnetic detection system and a multi-source emission signal separation method. The system comprises a transmitting system and an observation system, wherein the transmitting system comprises one or more transmitting devices which are arranged on the ground and are based on along grounding wire source; the observation system comprises a plurality of observation devices; each observation device comprises flight equipment, a single-component magnetic field sensor and a receiver; the number of the observation devices used for collecting single-component magnetic field data is larger than that of the transmitting devices; a plurality of observation devices carry out flight observation in a set observation area according to a preset formation to obtain a plurality of corresponding groups of observation signals; the set observation area is that the distance from any point to each transmitting device is smaller than N times of the to-be-detected depth, and N is a set value. Economic and flexible multi-component observation is realized, and more possibilities are provided for high-resolution, economic and rapid detection and underground structure information extraction of a deep large ore deposit.

The invention relates to a joint constraint random noise suppression method based on sparse regularization, and belongs to the technical field of geophysical exploration. The method specifically comprises the following steps: S1, inputting an original seismic record, and constructing an objective function of curvelet transform-second-order generalized total variation joint constraint denoising according to sparse features of noisy data in a curvelet domain and an image gradient domain; S2, converting the L1-L2 norm regularization model containing the curvelet transform constraint term into a standard basis pursuit noise reduction problem, and inverting a curvelet coefficient with the minimum L1 norm to obtain a seismic record after preliminary denoising; and S3, taking the preliminarily denoised seismic record as an input image, solving a denoising problem of the second-order generalized total variation constraint to realize random noise suppression of the joint constraint, and finallyoutputting seismic data with an enhanced signal-to-noise ratio. According to the method, the denoising effect on random noise in the seismic data is improved, and weak signal energy can be effectively protected, so that high-quality processing of subsequent seismic data and the reliability of a seismic geological interpretation result are guaranteed.

The invention discloses a prevention and treatment method for goaf water under condition of repeated mining of thick seam upper slices destructed by minitype coal mines. The method comprises the following steps: step 1, determining a target area of directional drilling; step 2, constructing a drilling field; step 3, detecting the goaf water-rich anomaly area of the roadway heading face by a transient electromagnetic method and a high-density direct current method; step 4, arranging conventional drilling holes in the roadway heading face for drilling verification, allowing roadway tunneling incase of no anomaly in drilling verification, and treating the goaf water by circulation of water exploitation-tunneling-water exploitation; step 5, performing treatment in case of gushing water in drilling in the process of drilling verification in step 4; step 6, performing treatment if the drainage volume of the conventional drilling holes of the heading face in step 5 tends to be stable for a long time. The goaf water is prevented and treated by combination of ground and downhole geophysical prospection-conventional drilling-directional drilling; advanced, efficient, safe, accurate, large drop and long-distance cut-off and diversion of the goaf water is achieved; and disaster caused by the goaf water is effectively treated.

The invention discloses a seismic data denoising method based on self-adaptive variational mode decomposition, and belongs to the field of oil and gas geophysical exploration. A seismic signal is processed by using the variational mode decomposition, the optimal parameters are selected by calculating a signal-to-noise ratio of decomposition results, and the seismic signal is processed by the variational mode decomposition of the optimal parameters to reduce noise in the seismic signal. The seismic data denoising method processes seismic data by the self-adaptive variational mode decomposition,and realizes seismic data noise suppression.

The invention relates to a transient electromagnetic detection method and system, belongs to the technical field of geophysical exploration, and specifically relates to a side-excited loop source ground well transient electromagnetic detection method and system. By exciting an anomalous body from the side through an ungrounded loop, a good coupling effect can be produced on a steep or upright low-resistance slab body. By using a receiving device to receive secondary field signals in a roadway or borehole, strong response signals can be received. By using a proposed data processing method to invert the received signals, an accurate interpretation result can be obtained.

The invention discloses an advanced detection method and an advanced detection system for a roadway. According to the advanced detection method for the roadway, apparent resistivity data is obtained;theoretical background apparent resistivity data are also acquired; the theoretical background apparent resistivity data and the correction coefficient corresponding to each measuring electrode are utilized to correct the apparent resistivity data detected by each measuring electrode; so as to eliminate the adverse influence of the tunnel cavity on the signal-to-noise ratio of the data, a problemof low signal-to-noise ratio of the data caused by influence of the tunnel cavity can be excellently solved, detection resolution and accuracy are improved, and quantitative data processing and explanation basis is provided for geophysical exploration personnel.

The invention discloses a seismic elastic impedance low-frequency information extraction method and system, and a storage medium. The method comprises the following steps: obtaining seismic data and actually measured elastic impedance data; inverting elastic impedance data through a neural network according to the seismic data; forward modeling seismic data are generated according to the elastic impedance data, and a seismic data loss value is obtained; obtaining a loss value of the elastic impedance according to the elastic impedance data and the actually measured elastic impedance data; obtaining a minimum total loss value and a low-frequency curve according to the seismic data loss value and the loss value of the elastic impedance; performing seismic inversion and reservoir prediction based on the minimum total loss value and the low-frequency curve; according to the scheme, the neural network method is introduced for seismic low-frequency information extraction, the extracted low-frequency characteristics are good, the calculation efficiency is high, the reservoir prediction precision can be remarkably improved, the exploration risk is reduced, and the method can be widely applied to the technical field of geophysical exploration.

The invention discloses a sparse representation regularization pre-stack AVO inversion method based on a fast orthogonal dictionary. The method is applied to the technical field of geophysical exploration interpretation, and in order to solve the problems that an existing KSVD dictionary inversion method is low in operation rate and large in number of controlled parameters, an objective function is constructed according to known angle gather seismic data, wavelet sequences, incident angle information and initial model parameters; adding regularization constraints; and finally, iteratively solving the regularization constraint objective function based on the orthogonal dictionary to obtain final model parameters. According to the method, the inversion effect equivalent to that of a KSVD dictionary method is guaranteed, and meanwhile the sparse inversion rate can be effectively increased.

The invention belongs to the technical field of geophysical exploration, and particularly relates to a high-precision data interpretation method for a shallow low-resistance abnormal body of a ground-air time domain electromagnetic system. The method comprises the following steps: simulating a shallow quasi-two-dimensional low-resistance abnormal body electromagnetic response numerical value basedon a long conductor source time domain electromagnetic system; performing random noise loading based on different signal-to-noise ratios on the analog value; adopting a regularization method to realize the downward continuation of the long wire source time domain electromagnetic response of the noisy signal; determining the optimal precision of the regularization continuation method under different signal-to-noise ratio conditions by adjusting regularization parameters; carrying out denoising processing on the electromagnetic response which does not meet the tolerance condition in the previous step by adopting an adaptive Kalman filtering algorithm; calculating the apparent resistivity and the apparent depth, and completing the apparent resistivity-apparent depth imaging. By means of themethod, high-precision data interpretation and imaging of noise-containing signal time domain electromagnetic response of the shallow anomalous body are achieved.

The invention belongs to the technical field of geophysical exploration signal processing, and relates to a three-dimensional seismic data multiple suppression method based on a local similarity coefficient. The method is based on a conventional three-dimensional surface related multiple wave pressing technology. The method comprises: calculating a local similarity coefficient spectrum of the multiple contribution gather of the contact survey line and the Radon transformation result; constructing a weighted threshold operator according to the similarity coefficient difference; using the Kronecker product of the original data and a weighted threshold operator, determining stationary phase overlay space, replacing a direct summation process of multiple wave connection measuring lines by superposition of Fresnel spaces, and the high-resolution multiple wave prediction method for the three-dimensional ocean seismic data is realized. The spatial false frequency generated by a conventional method is effectively suppressed, so that multiple wave prediction is more accurate, the precision and accuracy of multiple wave suppression are improved, and much convenience is brought to subsequentprocessing and explanation of seismic data processing.

The invention provides a high-temperature geothermal field comprehensive geophysical exploration system and a geothermal sweet spot area evaluation method. Large-area infrared remote sensing measurement and radioactive measurement are carried out, and three-component seismic longitudinal wave and seismic transverse wave data acquisition, ground three-dimensional broadband magnetotelluric data acquisition and ground high-density three-dimensional gravity data acquisition are carried out in a high-surface temperature and high-radioactivity area. Logging and DAS-VSP data in a drilled well in a high-temperature geothermal field exploration area are used for searching geophysical parameters which are abnormally sensitive to a high-temperature geothermal field, longitudinal wave velocity fields, transverse wave velocity fields, longitudinal and transverse wave velocity ratios, Poisson ratios, resistivity and density data volumes of underground three-dimensional spaces at the same depth position are compared and calibrated, a geothermal sweet spot area with high temperature, fault fracture development and rich underground water source supply is delineated according to the selected geophysical parameters which are abnormally sensitive to the high-temperature geothermal field, detailed investigation and comprehensive evaluation are carried out on the predicted geothermal sweet spot area, and the high-temperature geothermal field is quickly and efficiently explored and found at low cost.

The invention belongs to the field of comprehensive geophysical exploration methods, and particularly discloses an effective comprehensive geophysical method suitable for in-situ leaching sandstone type uranium-containing basin target area recognition. The method comprises the following steps: step 1, dividing an in-situ leaching sandstone type uranium-containing sedimentary basin into sedimentarybasin geodetic structure units, and determining basin depression and upheaval areas; step 2, dividing rock boundaries in the depression areas divided in the step 1 so as to preferably select favorable uranium mineralization sections; and step 3, on the basis of the uranium mineralization favorable section optimized in the step 2, determining underground geoelectric structure characteristics, anddetermining the spatial distribution and form of the sand body favorable for uranium mineralization. According to the invention, three geophysical methods of gravity, high-precision magnetic measurement and high-precision electromagnetic method are combined, the coverage is wide, the applicability is high, and the accuracy is high.

The invention provides a seismic data optimization method and system for high-precision seismic coherence attributes, and belongs to the field of oil and gas geophysical exploration. According to theseismic data optimization method for the high-precision seismic coherence attributes, convolution is carried out by using a Gaussian function envelope surface and an instantaneous phase attribute bodyto obtain optimized seismic data, and then the coherence attributes of the optimized seismic data is extracted. According to the method, coherent algorithm characteristics are utilized, for low-quality seismic data, a Gaussian function envelope surface is adopted to replace original wavelets, noise interference is reduced, and the original data is converted into optimized data suitable for fracture research through a third-generation coherent algorithm. After seismic data is optimized, intrinsic value coherent attribute extraction is carried out, and fracture characteristics can be highlighted more effectively.

The invention belongs to the field of geophysical exploration, and discloses hydrate stratum earthquake physical simulation test equipment and method based on a reflected wave field, and the equipmentcomprises a hydrate preparation device and a reflected sound wave test device. The hydrate preparation device is used for generating simulated hydrate; the reflected sound wave testing device is usedfor continuously emitting ultrasonic waves to the simulated hydrate in the generation process, receiving reflected waves, performing signal processing on the received reflected waves to identify andextract reflection characteristic information and acoustic velocity change information, and continuously monitoring the saturation degree of a simulated hydrate to obtain a corresponding relationshipbetween the reflection characteristic information and the acoustic velocity change information and the saturation degree of the simulated hydrate. According to the equipment and the method, hydrate stratum reflection characteristics and sound wave speed changes are acquired through hydrate stratum reflection wave field acquisition, the relationship with the hydrate saturation is obtained, and theequipment and the method have relatively important guiding significance for gas hydrate offshore seismic exploration data interpretation and gas hydrate saturation estimation.

The invention relates to the field of geophysical exploration equipment, and specifically, relates to a short dead zone magnetic resonance emission device and a control method based on wide configuration harmony. A PC upper computer and a master control module are provided, according to a command of the upper computer, a DC-DC converter is controlled to charge an energy-storage capacitor, and thecharging energy comes from a storage battery; by sending a PWM wave, a H bridge emission module and a coil are controlled to perform bipolar pulse emission, and emission energy comes from the energy-storage capacitor; by controlling a first switch driving module, on and off of a first switch are controlled, by controlling a second switch driving module, on and off of a second switch are controlled, and by control a third switch driving module, clamp voltage of a clamping module is controlled; based on a negation circuit used for negation of a switch control signal of a master control module, complementation is executed for first switch and second switch switch-on signals. The device and the method provided by the invention solve a problem that the signal itself has relatively low amplitude, is almost completely submerged in noise after energy release time decay, brings great difficulty in follow-up data processing and inversion and has strong impact on detection effect, can effectivelyreduce turn-off time of an emission system and reduce dead zone time of magnetic resonance detection, and consequently can improve signal amplitude.

The invention discloses a sound wave curve correction method for seismic processing, and relates to the technical field of geophysical exploration and development, which comprises the following steps:acquiring and calculating a logging curve; carrying out well-to-seismic comparison to determine the number of well logging curve decomposition stages, and completing well logging curve decomposition;analyzing statistical characteristics of the multi-well decomposition curve, selecting the decomposition curve to determine standardized parameters, and performing standardized correction on the logging curve; establishing a suitable rock physical model, calculating a rock physical model line, and calculating a sound wave curve based on the rock physical model; determining a sound wave curve abnormal layer section; and obtaining GR, RD and DEPTH of a normal interval of the sound wave value and a rock physical model to calculate a sound wave curve, establishing a sound wave curve correction model, and completing correction of the sound wave curve for an abnormal interval of the sound wave. By applying the method, acoustic wave curve correction in seismic processing can be effectively achieved, the influence of non-geological factors such as borehole diameter collapse and mud invasion is reduced, the acoustic wave curve quality is greatly improved, and the reliability of borehole seismic calibration is improved.

The invention relates to an electric detection method and device, belongs to the technical field of geophysical exploration, and specifically relates to a side-powered ground well DC electric detection method and device. A stable DC electric field is established at ground power supply electrodes, and the azimuth of an anomalous body relative to a measuring line is judged according to the difference of potential difference signals generated by different electrodes at the measuring line. The collected potential difference signals contain the information of a surrounding geological body with anomalous resistivity. A target body can be detected by processing and analyzing the overall data of the measuring line. The advantages, such as high transmitting power of the ground electrodes, various observation systems and close distance between an underground receiving electrode and the anomalous body, are utilized, and the detection effect can be improved.

The invention relates to a method for delineating a favorable metallogenic section of uranium polymetallic ore, and relates to the field of geophysical exploration. The method comprises the following steps: firstly, collecting existing geophysical exploration data, determining geologic features of a measurement area, and formulating a geophysical work deployment scheme; then performing gravity measurement, magnetic measurement and induced polarization scanning measurement according to a geophysical work deployment scheme, obtaining a gravity anomaly separation result through a gravity measurement method, obtaining magnetic anomaly data through a magnetic measurement method, obtaining an apparent resistivity value and a polarizability value through induced polarization scanning measurement, and analyzing the structure distribution of the target geologic body; then sounding the depth of the target geologic body by using an induced polarization method and an audio magnetotelluric method, and determining the deep extension condition of the target geologic body; and finally, according to the deep extension condition of the target geologic body and the geological information of the target geologic body, determining a favorable metallogenic section in the measurement area so as to obtain the favorable metallogenic section of the uranium polymetallic ore.

The invention discloses an audio magnetotelluric data noise interference filtering method and an audio magnetotelluric data noise interference filtering system, which relate to the technical field ofgeophysical exploration. According to the audio magnetotelluric data noise interference filtering method, a generalized morphological filtering method is adopted to filter data with low-frequency noise interference, the data with peak pulse noise interference is filtered by adopting a wavelet transform method, low-frequency noise interference can be filtered out, peak pulse noise interference canbe filtered out, and various noise interferences can be filtered out at the same time, thus high-quality original data are obtained, the working efficiency is improved, the field workload is reduced,and geological prospecting work can be better served.

The invention discloses a wave impedance inversion method based on a joint dictionary, which is applied to the technical field of geophysical exploration and interpretation, and aims to solve the problem that the conventional sparse dictionary is obtained through high-frequency-band logging data learning and lacks logging data low-frequency-band information. The method comprises the following steps: firstly, training a joint dictionary, specifically, obtaining the joint dictionary containing high-frequency and low-frequency information through logging data learning containing low-frequency information and high-frequency information, the joint dictionary comprising a low-frequency dictionary and a high-frequency dictionary; then, constructing an initial model containing a low-frequency component by using the low-frequency dictionary; and finally, performing sparse inversion on the initial model by using the high-frequency dictionary, thereby obtaining a wave impedance sequence containing a low-frequency component and a high-frequency component. Compared with the prior art, the inversion result of the method is closer to a real model.