20 results about "Magnetotelluric sounding" patented technology

The invention discloses a magnetotelluric sounding measurement method for multidirectional aggregation observation, and the method comprises the steps: building a novel device layout: designing a reasonable measurement point layout scheme according to geological features and electromagnetic response distribution; processing data and establishing an unstructured grid: acquiring an electromagnetic field component, completing data acquisition, and inputting the processed electromagnetic field data into an unstructured grid model; impedance tensor calculation: on the basis of the unstructured grid, performing impedance calculation by utilizing multi-component electromagnetic field data and combining an interpolation idea, and constructing an extended impedance tensor of an electromagnetic field component to obtain an impedance value component; and three-dimensional inversion and visualization: performing three-dimensional inversion through a vector finite element method to obtain an inversion result. According to the method, richer observation data are provided for deep geologic structure inversion.

The invention discloses a two-dimensional inversion operation method, system and device for a magnetotelluric sounding profile, a medium and a product, relates to the technical field of magnetotelluric sounding exploration, and aims to solve the problem that existing inversion based on nonlinear conjugate gradients is highly dependent on an initial model. The method comprises the following steps: firstly, acquiring measured data including measured point measured kilometer network coordinates, apparent resistivity and phase data; a two-dimensional inversion profile with complete data of each measuring point is constructed according to linear projection, and data interference and distortion are eliminated through preprocessing; the method comprises the following steps: firstly, constructing a uniform half-space model, and carrying out two-dimensional nonlinear conjugate gradient TE mode inversion to obtain a rough two-dimensional resistivity model; and taking the rough model as an initial model, carrying out TM mode inversion to obtain a target two-dimensional resistivity model, and finally carrying out geological interpretation by combining rock physical property, geology and drilling geophysical prospecting data. According to the method, through a strategy of first TE and then TM, dependence of an initial model is reduced by means of a TE mode, resolution capability is improved by means of a TM mode, false anomalies are reduced, reliability of a target model can be improved, and accurate data support is provided for mineral exploration and deep geologic structure research.

The invention discloses a karst landform area underground two-dimensional geological structure modeling method and system, and belongs to the technical field of geophysical exploration. Aiming at the problem of poor geological modeling precision caused by low signal-to-noise ratio, high physical property heterogeneity and lack of drilling data of seismic data in a karst landform area, the method comprises the following steps: acquiring electrical property, earthquake and geological multi-source information through magnetotelluric sounding, two-dimensional earthquake and shallow surface geological survey; processing is carried out by using the borehole-side sounding to constrain the electrical structure; the fracture is identified by integrating the difference between the electrical gradient band and the seismic wave group; for the deep area, utilizing an electrical marker bed and a seismic wave group to track the stratum, and for the shallow area, recovering the stratum form based on the earth surface occurrence and the drilling thickness; and evaluating whether the stratigraphic sequence and the thickness conform to a regional rule or not by blocks, and iteratively optimizing the model. According to the method, the modeling precision and reliability of the underground two-dimensional geological structure in the karst landform area can be remarkably improved, and the method is low in cost, easy and convenient to operate and suitable for low-exploration-degree areas.

This invention discloses a comprehensive prediction method for oil-uranium-hot dry rock-shale oil in sedimentary basins, belonging to the field of geological exploration technology. This method involves using effective geophysical methods to extract basic geological background information, constructing a three-dimensional spatial framework of the basin, clarifying the correlation between structures, strata, and igneous rocks, calculating the correlation coefficient and intercept of airborne gravity and magnetic anomalies, initially screening key target areas, extracting key information on energy resource accumulation / mineralization, performing two-dimensional or three-dimensional characterization of target geological bodies, combining magnetotelluric sounding inversion profiles with seismic and drilling data, adjusting core parameter settings, and overlaying oil-uranium-hot dry rock-shale oil resource accumulation / mineralization evaluation information to obtain comprehensive energy resource prediction results. This method can provide scientific and technical support for basic geological research on oil-uranium-hot dry rock-shale oil in sedimentary basins and provide comprehensive and reliable prediction of resources.

The invention relates to the technical field of audio magnetotelluric, in particular to an audio magnetotelluric probing data acquisition system which comprises a data acquisition end, a detection signal transmission line, a feedback transmission line and a processing end. In each unit module, each conductive contact is distributed with an identifier, and the processing module is used for detecting the conductive contact which is currently in a conducting state, taking the identifier of the conductive contact which is in the conducting state as a form indicator, and sending the form indicator to the processing end. And the processing end is used for determining the actual form of the detection signal transmission line according to the form indicator of each unit module, and determining the position coordinate of the data acquisition end according to the actual form. The method can effectively reduce the data distortion risk and error risk when the data acquisition end is used in a large scale, guarantees the accurate detection process, and provides a guarantee for the actual application process of audio magnetotelluric exploration.

The application discloses a kind of karst landform area underground two-dimensional geological structure modeling method and system, belong to geophysical exploration technical field.For the problem that karst landform area seismic data signal-to-noise ratio is low, physical property is strong inhomogeneous, drilling data is deficient and leads to poor geological modeling precision, the present application obtains electrical property, seismic and geological multi-source information by magnetotelluric sounding, two-dimensional seismic and shallow surface geological survey;With well-by-side sounding constraint electrical property structure processing;Comprehensive electrical property gradient zone and seismic wave group difference identification fracture;Deep region is tracked stratum using electrical property marker layer and seismic wave group, and stratum morphology is restored based on surface occurrence and drilling thickness in shallow region;Whether stratum sequence and thickness meet regional rule is evaluated by block, and model is iteratively optimized.The present application can significantly improve the modeling precision and reliability of underground two-dimensional geological structure in karst landform area, and is low in cost, easy to operate, applicable to low exploration degree region.

The application belongs to the technical field of geophysical exploration, and relates to a magnetotelluric sounding data processing method and system based on compressed sensing, which comprises the following steps: acquiring four-component time domain data, constructing a sampling matrix A according to the plane coordinates of a collection station and a high-resolution grid of a target in a study area, constructing a sparse representation dictionary D, making a magnetotelluric target signal be represented as the product of the sparse representation dictionary D and a sparse coefficient X, solving the sparse coefficient X based on a compressed sensing optimization model, calculating a frequency domain signal on the high-resolution grid by using the sparse coefficient X obtained through iterative solving and the sparse representation dictionary D, obtaining reconstructed electromagnetic field frequency domain data, and modifying the reconstructed electromagnetic field frequency domain data by using Maxwell equation constraints. The application breaks through the Nyquist sampling limit by utilizing the frequency domain sparsity of magnetotelluric data, and solves the problems of low resolution, poor detail recovery and weak physical consistency of a traditional interpolation method, so that the underground geological structure information can be more accurately recovered.

The application discloses a kind of deep matter thermal state quantitative estimation method based on electrical structure model, first according to the magnetotelluric sounding data collected, establish the deep three-dimensional electrical structure model of study area;Again, according to the relationship between rock conductivity and its temperature, the relationship between the total conductivity and temperature of the upper mantle in solid mixed system and solid-melt mixed system is considered respectively, the quantitative relationship model of the total conductivity of the upper mantle and temperature, rock melting percentage content is established;Finally, according to the quantitative relationship model, the conductivity data measured by actual magnetotelluric is brought in, the rock melting percentage content and temperature in the scale range of the upper mantle are calculated, and the deep thermal structure model of exploration area is established.The application can directly obtain deep temperature and rock melting percentage content by combining the electrical structure model established by rock physics and magnetotelluric sounding.

The invention discloses a magnetotelluric sounding method and a magnetotelluric sounding system for geothermal exploration. The magnetotelluric sounding method comprises the following steps: acquiring magnetic field intensity and frequency characteristics of a working area; determining observation information of the magnetotelluric observation system according to the magnetic field intensity and frequency characteristics of the working area, and obtaining magnetotelluric data based on the observation information; performing correlation parameter comparative analysis on the preprocessed magnetotelluric data to obtain a correlation parameter statistical comparison result; and establishing a geoelectric model according to an inversion result based on the related parameter statistical result, and generating an address color release profile map according to the geoelectric model so as to perform geothermal resource detection. According to the invention, the problems of shallow exploration depth, low interpretation precision, large error and the like in the existing geothermal geology survey can be solved.

The invention provides a three-dimensional seismic exploration method and system based on multi-source geological data fusion, and the method comprises the steps: carrying out the data standardization of obtained multi-source heterogeneous geological data of a target work area, and generating a standard data set; wherein the multi-source heterogeneous geological data comprises seismological observation data, drilling data and magnetotelluric sounding data; based on the seismic data and the logging data in the standard data set, feature correlation analysis is carried out through a pre-trained deep learning model to obtain a lithology sensitive factor data body, and the lithology sensitive factor data body is used for representing the response confidence coefficient of the seismic data to lithology change; and establishing an objective function of seismic and electromagnetic data joint inversion by taking the lithology sensitive factor data volume as a dynamic constraint, and obtaining comprehensive physical property data by solving the objective function, the comprehensive physical property data being used for constructing a three-dimensional geologic model. The method can improve the precision and reliability of seismic exploration.

The application provides a magnetotelluric sounding data splicing processing method and system, and the method comprises the following steps: (1) acquiring magnetotelluric sounding data and regional rock electrical property parameter data corresponding to different measuring points of adjacent blocks; (2) performing quality inspection on the magnetotelluric sounding data; (3) performing quality evaluation and classification on the magnetotelluric sounding data; (4) performing standardization processing on the magnetotelluric sounding data; (5) performing pretreatment on the magnetotelluric sounding data; (6) performing normalization processing on the magnetotelluric sounding data; (7) performing splicing processing on the normalized magnetotelluric sounding data, performing data smoothing transition on the data of the overlapping area of adjacent blocks, and performing inspection on the residual distribution of the data before and after splicing; (8) performing joint inversion on the spliced data; and (9) performing analysis on the depth domain resistivity data body. The application has reasonable design and can be applied to secondary continuous processing of magnetotelluric data collected in different periods of oil and gas exploration.

The present application relates to the technical field of geophysical exploration, and discloses a deep learning inversion method and system for magnetotelluric sounding, comprising: constructing a trained magnetotelluric one-dimensional inversion model; converting measured apparent resistivity and measured phase data into interpolated apparent resistivity and interpolated phase data, using a Savitzky-Golay filter to construct a target multi-window Savitzky-Golay filter set to obtain smoothed apparent resistivity and smoothed phase data, and constructing an inversion apparent resistivity-phase data set based on the smoothed apparent resistivity and smoothed phase data; inputting the inversion apparent resistivity-phase data set into the trained magnetotelluric one-dimensional inversion model to obtain a corresponding inversion resistivity geoelectric model set, and obtaining a target resistivity geoelectric model based on the inversion resistivity geoelectric model set; the present application solves the problems of low accuracy and poor practicability in the existing deep learning inversion method for magnetotelluric sounding.

This application relates to the field of geological exploration, particularly to methods, apparatus, electronic equipment, and storage media for well site target area surveying in deep geothermal reservoirs. The method includes: acquiring gravity data of the area to be surveyed; determining buried hills and / or uplift zones based on the gravity data, and designating these zones as preferred target areas; determining the magnetotelluric signals of the preferred target areas using magnetotelluric sounding; and determining the electrical data of the preferred target areas based on the magnetotelluric signals. This application improves the efficiency of well site selection.

The invention provides a denoising method and system for human noise of a magnetotelluric sounding signal, and relates to the technical field of magnetotelluric sounding data processing. According to the method, linear trend removal and amplitude standardization preprocessing is carried out on multi-channel time sequence data, and decomposition parameter self-adaptive optimization is realized in combination with variational mode decomposition, envelope entropy evaluation and a sparrow search algorithm; a useful mode and a noise mode are distinguished by using permutation entropy, a Hankel matrix is constructed for the noisy mode, and de-noising is completed through singular value decomposition and matrix truncation reconstruction. The method can effectively identify and suppress human noise, and improve the signal-to-noise ratio and interpretation reliability of the magnetotelluric sounding signal.

The application discloses a method for intelligently selecting power spectrum of magnetotelluric sounding method based on deep learning classification, and specifically comprises the following steps: S1: segmenting MT electric field and magnetic field time series data collected in the field, calculating power spectrum of each time series, and obtaining MT sub-power spectrum; S2: respectively performing impedance estimation on all MT sub-power spectrum and total power spectrum after full stacking, and respectively calculating apparent resistivity and phase; S3: using apparent resistivity and phase after full stacking to perform Rhoplus inversion, and calculating fitting difference between resistivity and phase obtained by inversion and apparent resistivity and phase of the sub-power spectrum. The method for intelligently selecting power spectrum of magnetotelluric sounding method based on deep learning classification has the effects that in MT measured data processing, manpower cost can be greatly saved, uncertainty and randomness of manual selection of power spectrum can be avoided, and the influence of noise on impedance estimation of MT data can be effectively inhibited.

This application belongs to the field of geophysical exploration technology, specifically relating to a magnetotelluric sounding station layout optimization method and system based on sensitivity analysis. The method includes: establishing a three-dimensional subsurface structure model; integrating multi-source geological data to establish a three-dimensional subsurface structure model; discretizing the three-dimensional subsurface structure model into N grid cells, using the resistivity of each grid cell as the model parameter; constructing a parameter sensitivity matrix of the model parameters to the observation data; constructing a multi-objective optimization objective function; converting the multi-objective optimization objective function into a minimization objective function; and solving it using a non-dominated sorting genetic algorithm with an elitist strategy to obtain the optimal solution. This application changes the traditional method's reliance on the subjective experience and judgment of technical personnel, significantly improving the scientific rigor and consistency of station layout decisions.

The invention discloses a salt lake low-resistance area magnetotelluric sounding observation duration adaptive regulation and control system and method, and relates to the technical field of geophysical exploration, and the method comprises the steps: selecting a measurement point before observation starting, collecting an electric field and geomagnetic time sequence in real time, calculating the change rate indexes of an electric field and a magnetic field, and obtaining the overall stability index of an electromagnetic field; establishing a first stable time period through threshold judgment, and starting observation pre-activation and interference source analysis; arranging a magnetic induction coil array based on the first stable time period, calculating electric field noise energy density and direction interference index in each direction, screening a low interference direction and locking a main observation direction; acquiring an electric field component in a main direction in real time, calculating effective electric field intensity, comparing the effective electric field intensity with a low-resistance penetration threshold value, judging the penetration capability, and determining whether to start a delay acquisition mechanism or not; comprehensively constructing an observation weighting factor, and correcting the final acquisition time; according to the method, the observation data quality and stability in the salt lake area low-resistance environment are effectively improved, and effective acquisition of deep electromagnetic response is ensured.

A controllable source audio frequency magnetotelluric sounding transmitting end electrode arrangement system and method belong to the technical field of electromagnetic prospecting, and particularly relate to the technical field of electromagnetic sounding electrode arrangement. The system and method solve the technical problem that the current CSAMT transmitting end electrode arrangement technology cannot simultaneously achieve the core target of "greatly reducing resistance and increasing current + zero field source distortion + high construction feasibility". The system and method comprise a main dipole unit and A-side and B-side distributed auxiliary electrode arrays. The main dipole unit is composed of A0 and B0 main transmitting electrodes. The A-side auxiliary electrode array is arranged in a direction away from the B0 along a dipole axis, the B-side auxiliary electrode array is arranged in a direction away from the A0 along the dipole axis, and the double-side arrays are completely symmetrical along the dipole center. All same-side electrodes are connected in parallel at an equal potential to a transmitter, and the transmitting current is in-phase and equal potential. The system and method only need short electrodes and artificial shallow pits for arrangement, the grounding resistance is greatly reduced, the transmitting current is steadily increased, and the ideal horizontal electric dipole field source characteristics are strictly guaranteed without field source distortion.

The application belongs to the technical field of geophysical exploration, and relates to a magnetotelluric sounding data processing method and system based on compressed sensing, which comprises the following steps: acquiring four-component time domain data, constructing a sampling matrix A according to the plane coordinates of a collection station and a high-resolution grid of a target in a study area, constructing a sparse representation dictionary D, making a magnetotelluric target signal be represented as the product of the sparse representation dictionary D and a sparse coefficient X, solving the sparse coefficient X based on a compressed sensing optimization model, calculating a frequency domain signal on the high-resolution grid by using the sparse coefficient X obtained through iterative solving and the sparse representation dictionary D, obtaining reconstructed electromagnetic field frequency domain data, and modifying the reconstructed electromagnetic field frequency domain data by using Maxwell equation constraints. The application breaks through the Nyquist sampling limit by using the frequency domain sparsity of magnetotelluric data, solves the problems of low resolution, poor detail recovery and weak physical consistency of a traditional interpolation method, and more accurately recovers underground geological structure information.

The present application relates to the field of geophysical exploration technology, in particular to a method for selecting favorable oil and gas structure area in low exploration degree area of piedmont thrust belt. The method comprises the following steps: selecting an oil and gas prospective area, conducting surface geological survey based on regional geological map, preparing surface fault structure outline map and determining main structure trend; wavelet decomposition of gravity data to determine the fitting result of basement fault; deploying magnetotelluric sounding profile perpendicular to the structure trend to obtain electrical property model and compile basement fault map; deploying sounding profile and wide line 2D seismic profile parallel to the structure trend to determine low resistance belt; calibrating the depth of the basement to compile the burial depth map, and tracking the hidden strike-slip fault to compile the distribution map; grid partitioning, standardization assignment, and mean grid; and combining with the gas content of the drilling to determine the boundary and select the favorable oil and gas structure area. The present application adopts surface measurement and multiple geophysical technologies, which is low in cost, simple in operation, high in efficiency, suitable for low exploration area, and can improve the selection accuracy and provide strong technical support for the selection of oil and gas exploration target area.