32 results about "Focal mechanism" patented technology

The invention provides an earthquake evaluation method based on multi-type geophysical data. The method includes: obtaining intraplate natural earthquake data, surface elevation data, Bouguer gravity anomaly data, aeromagnetic anomaly data, seismic wave tomography, crustal GPS movement rate and focal mechanism solution in the target area; constructing a planar grid in the target area Based on this, the intra-plate natural seismic data, surface elevation data, Bouguer gravity anomaly data and aeromagnetic anomaly data are processed by plane grid respectively; based on the above data of plane grid, the plane distribution of the strong earthquake area in the target area is determined Figure: superimpose the surface elevation map, the planar distribution map of the strong earthquake area in the target area and the seismic wave tomography, combine the GPS movement rate of the crust and the solution of the focal mechanism, analyze the movement of the crust on both sides of the strong earthquake area, analyze the relationship between the strong earthquake area and The matching relationship of the geological structure of the crust, so as to determine the geological origin of the strong earthquake zone.

The invention discloses a rock sample hydraulic fracture morphology acoustic emission diagnosis experimental method and device, wherein the rock sample hydraulic fracture morphology acoustic emission diagnosis experimental method comprises the steps: a sensor array of a three-dimensional rock sample space is optimized to design, a rock sample emission speed filed is actively positioned and tested, and rock samples are done with a hydraulic fracturing physical simulation experiment, then are analyzed through sound wave arrival time recognition sound wave data, screen effective acoustic emission signals, and position acoustic emission event points in real time. Effective acoustic emission signals are analyzed through a focal mechanism and clusters, thereby obtaining extensional fracture and shear fracture spatial distribution regulations. The influence of geological stress conditions, natural fracture development degrees, net pressure construction and fluid viscosity to a hydraulic fracture extended mechanism is analyzed through many time experimental results of the hydraulic fracturing physical simulation experiment. The rock sample hydraulic fracture morphology acoustic emission diagnosis experimental method and device solves the difficult problems that effective signals in large size unconventional samples are difficult to collect and are low in positionaI accuracy.

The invention belongs to microseism monitoring data processing technique and discloses a focus positioning and focus mechanism joint inversion method utilizing P wave first motion constraint. The method includes steps of performing lattice point dispersion on a focus position space and a focus mechanism space; searching all lattice points of focus parameters; correcting a seismic record by utilizing the focus mechanism; searching the focus position; outputting focus parameter results after searching is over. According to the invention, aiming at double-couple focus parameter inversion in ground microseism, the focus positioning and the focus mechanism are put in joint inversion for searching and solving. P wave first motion polarity corresponding to the focus mechanism is utilized for correcting the seismic record and constraining focus positioning. In this way, the inversion precision of the focus positioning and the focus mechanism can be improved at the same time. At the same time,optimization is made on calculation of the P wave first motion polarity in positioning and searching, so that calculation precision and calculation efficiency are improved substantially.

The invention discloses a ground microseismic location method and system combined with focal mechanism inversion. The method includes the steps of: determining the theoretical travel time table by using the P wave and S wave velocity models according to the observation system and the target area; obtaining the theoretical travel time table according to the theoretical travel time table The amplitude of the microseismic data track is corrected according to the theoretically predicted polarity before stacking; the source position is determined according to the stacked energy of the polarity corrected amplitude. Because the microseismic location method of the present invention's joint focal mechanism rapid inversion utilizes the waveform information of P waves and S waves in the data, the focal mechanism solution inversion calculation is fast and stable, and can effectively solve the problem of radiation patterns caused by complex focal mechanisms. Improve the accuracy of scanning superposition positioning; and the method of the present invention does not need to manually pick up the first arrival of P wave and S wave, and can automatically detect and locate microseismic events, further avoiding the impact of picking errors on positioning accuracy.

The invention provides a microseism event forward modeling method based on reservoir geomechanical parameters. The microseism event forward modeling method based on the reservoir geomechanical parameters comprises the steps that pressure valuation is conducted on initial hydraulic fracturing, and the finite element method is used for model simulation; the stress of a rock unit at each specific moment is calculated according to time variation; whether the current rock unit is fractured or not is judged according to a stress calculation result in combination with rock fracturing criteria; porosity parameters are calculated; if the rock unit fractures, the magnitude of a focus is calculated in combination with a microseism focal mechanism; simulation at all moments is completed. According to the microseism event forward modeling method based on the reservoir geomechanical parameters, the calculation result can truthfully reflect the actual change conditions of a subsurface reservoir, and the method can be used for prediction of a microseism event in the process of subsurface cracking and fracturing.

The invention discloses a method for monitoring microseismic positioning and expansion mechanism of hydraulic fracturing fractures in coal rocks. Firstly, microseismic sensors are arranged according to actual conditions to collect original waveform signals in the fracturing process; on this basis, an event screening window with an updateable length is proposed. , use the long and short time window method to scan the data of each channel to identify effective microseismic events; filter the effective microseismic events induced by hydraulic fracturing of coal and rock mass by defining the waveform sensitivity value, and then use the local AIC method to obtain high-precision arrival time of microseismic events, and Calculate the location of the fracture source, and at the same time invert the focal mechanism according to the P wave amplitude and initial motion information; finally, combine the microseismic location and focal mechanism information to reveal the spatial distribution and fracture mechanism of hydraulic fracturing fractures, and determine the hydraulic pressure of the coal seam. The impact range of fracturing, which has guiding significance for real-time dynamic adjustment of parameters during fracturing, determination of fracturing radius, and reservoir evaluation.

The present invention provides a rock feature-based focal mechanism inversion method and device, which relate to the technical field of microseismic monitoring. Firstly, the microseismic signals in the target monitoring area are collected; and then based on the target relationship model, the target corresponding to the microseismic signal is predicted. Rock characteristics; finally, based on the target rock characteristics, the focal mechanism of the rupture event in the target monitoring area is inverted. The present invention can ensure the authenticity of the data used in the inversion of the source mechanism by collecting the micro-seismic signals in the target monitoring area, and can obtain the fracture in the target monitoring area by predicting the target rock characteristics corresponding to the micro-seismic signals according to the target relationship model. The rock characteristics of the event occurrence, which can avoid the multi-solution of the focal mechanism, and then obtain a real, effective and unique focal mechanism.

The invention provides a tectonic geodetic survey mapping method based on ArcEngine. With the aid of the function of an ArcGIS layer, a digital elevation model of an area where a structure is located is loaded on a map as a base to represent the landscape of the structure area; according to the location of a measuring station, a horizontal deformation value, a level deformation value and deformation error information, the visual expression function of a 3D geographic information system is called using ArcEngine on a digital elevation model of an area where the measuring station is located to draw a GPS deformation field and a level deformation field at the location of the measuring station; according to the location of an epicenter, seismic moment magnitude, and the strike angles, tilt angles and sliding angles of the first motion nodal planes of two P-waves, the visual expression function of the 3D geographic information system is called using ArcEngine on a digital elevation model of an area where the epicenter is located to draw a focal mechanism solution at the location of the epicenter; and mapping parameters are set, and then, vectors are output for mapping. Visual tectonic geodetic survey mapping is realized based on ArcEngine. The problem that parameters are repeatedly adjusted using a command line is avoided. The efficiency of drawing is improved.

The invention discloses a hydrofracture focal mechanism inversion method and system, and the method comprises the steps: calculating the azimuths of all detectors relative to a hydrofracture focus according to the horizontal coordinates of all ground detectors; building a horizontal layered speed model through employing the interval transit time logging data of a hydraulic fracture well; calculating the take-off angle of each detector relative to the focus on the basis of the horizontal layered speed model, the focus positioning results, obtained through the processing of former microseism data, of a microseism event and the coordinate positions of the detectors; Determining the polarity of a first motion of a P wave according to the correlation coefficient of each recording channel to a standard channel; taking the azimuths and take-off angles of all detectors and the polarity of the first motion of the P wave as input, and obtaining the nodal plane solution of a fault corresponding to a minimum contradiction symbol ratio. The method achieves a high-efficiency and practical processing flow of the hydrofracture focal mechanism inversion through employing the information of the first motion of the P wave.

The invention discloses a microseismic interference positioning method based on instantaneous phase cross-correlation weighting. N seismic waves of microseismic events are obtained through N geophones, and the seismic waves are componentized; the geophones are combined one by one to form a non-repetitive wave detection. pair; calculate the time-domain cross-correlation waveform and instantaneous phase cross-correlation waveform in each component; weight each time-domain cross-correlation waveform and its corresponding instantaneous phase cross-correlation waveform in each component to obtain the corresponding weighted cross-correlation Waveform; in each component, the theoretical direct wave travel time difference is used to migrate and superimpose the corresponding weighted cross-correlation waveforms of each channel to obtain the interference imaging profile; according to the multiplication of the interference imaging profiles in multiple components, the comprehensive interference imaging profile is obtained to determine the microseismic The location of the event. Through the above method, the problem of the polarity change of the microseismic waveform caused by the complex source mechanism is solved, and the influence of high-amplitude noise on the time-domain cross-correlation and subsequent stacking calculation is reduced.

The invention provides a three-component P-wave initial motion seismic focus mechanism inversion method and device. The method may include the following steps: 1) three component P-wave initial motionsymbols are extracted from microseismic ground shallow well monitoring data; 2) symbol correction is performed on X and Y component P-wave initial motion symbols; 3) a seismic focus model is selected; according to the microseismic ground shallow well monitoring data, values of seismic focus model parameters are solved to determine a seismic focal mechanism solution; 4) lattice point dispersion isperformed in a seismic focal mechanism space; 5) lattice points in the seismic focal mechanism space are searched. In a searching process, a Z component P-wave initial motion symbol corresponding tothe seismic focal mechanism is calculated; 6) degrees of matching is calculated; and 7) the seismic focal mechanism corresponding to a component with a maximum degree of matching is selected as an inversion result. The inversion method and device disclosed in the present invention are used for constraining inversion of the seismic mechanism via three components at the same time, accuracy of inversion can be increased, and multiplicity of solutions of the inversion result can be reduced.