Deep target time-frequency electromagnetic constraint inversion interpretation method and device, storage medium

Abstract

The application belongs to the technical field of electromagnetic exploration, and discloses a deep target time-frequency electromagnetic constraint inversion interpretation method, device and storage medium. On the basis of free inversion of electric path component data, a time-frequency electromagnetic multi-element joint modeling constraint inversion interpretation method for deep target layers is provided, that is, according to the resistivity free inversion result and deep structure information reflected by gravity anomaly, a deep initial geological model is established, the shallow cover geoelectric structure is controlled and constrained according to seismic and drilling data, fine inversion is carried out for the deep target layer, and various constraint mechanisms are established through multi-element modeling in the inversion process. The application overcomes the defects of S equivalent effect in the prior art, reduces the multi-solution property and uncertainty, and significantly improves the resolution of the deep target layer, thereby providing rich and reliable fine electrical layered abnormal information for deep basin structure and stratum rock property interpretation research. The application is suitable for deep basin structure and stratum rock property interpretation research.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of electromagnetic prospecting, and relates to a deep target time-frequency electromagnetic constraint inversion interpretation method, device and storage medium. BACKGROUND

[0002] The deep layer of a basin is rich in energy resources such as oil and gas and geothermal energy, is an important new layer system and new field for replacing oil and gas reserves, and is an important layer system and field for searching for oil and gas and geothermal resources.

[0003] The seismic data quality of the middle and shallow layers of a basin is generally good, but the deep layer of the basin has the characteristics of complex structure and developed igneous rocks due to long time and multiple tectonic movements, and effective reflection data are often difficult to obtain through seismic exploration, so it is difficult to clearly understand the deep basin structure and stratum rock properties only by relying on seismic data.

[0004] Due to the limitations of a single geophysical method and the multi-solution and uncertainty of geophysical inversion results, in order to implement the deep target of a basin, a method of joint modeling and constraint inversion interpretation must be used, that is, a geological model is established by using seismic data for the shallow layer, a deep geological model is established by combining gravity and electromagnetic non-seismic data for the deep layer where the seismic data are unclear, and then inversion interpretation is performed to improve the resolution of deep exploration, so as to obtain rich and reliable geophysical information of the deep exploration target.

[0005] Time-frequency electromagnetic method (TFEM) is a new high-power artificial field source electromagnetic exploration method developed in recent years, which significantly improves the effective detection depth compared with traditional natural field source electromagnetic methods such as magnetotelluric sounding method (MT) and continuous electromagnetic array profile method (CEMP). At present, the TFEM method usually uses the electric channel component to collect data for inversion because the magnetic channel component is easily disturbed by the surface conditions. However, the existing conventional inversion method has the problem of "S" equivalent effect, which causes the deep electrical structure layer obtained by free inversion of the electric channel component to be relatively macroscopic and the resolution to be not high, the internal electrical property change is not clear, the identification accuracy of the deep basin geological structure and stratum rock properties is restricted, and this is not conducive to deep target exploration research. SUMMARY

[0006] The purpose of the present application is to provide a deep target time-frequency electromagnetic constraint inversion interpretation method to break through the technical bottleneck of low resolution of conventional electromagnetic deep exploration.

[0007] The second purpose of the present application is to provide a deep target time-frequency electromagnetic constraint inversion interpretation device.

[0008] The third purpose of the present application is to provide a storage medium of the deep target time-frequency electromagnetic constraint inversion interpretation method.

[0009] The application is adopted with the technical scheme as follows to realize the above-mentioned purpose.

[0010] A deep target time-frequency electromagnetic constraint inversion interpretation method, comprising the following steps performed in sequence,

[0011] S1, time-frequency electromagnetic collection and gravity collection are carried out in a study area, and stratum rock physical property data are statistically analyzed to obtain time-frequency electromagnetic collection data, gravity collection data and stratum rock physical property characteristics of measuring points;

[0012] S2, the time-frequency electromagnetic collection data of the measuring points are preprocessed to obtain amplitude and phase data of each measuring point, and the gravity collection data of the measuring points are preprocessed to obtain Bouguer gravity anomaly data of each measuring point;

[0013] S3, the amplitude and phase data of each measuring point are used to perform first resistivity inversion to obtain an initial resistivity inversion profile in the depth domain, and further obtain a macroscopic geoelectric model;

[0014] characterized in that after step S3, the following steps are performed in sequence:

[0015] S4, an initial resistivity model of a middle-shallow cover layer is constructed according to the macroscopic geoelectric model, a second resistivity inversion is performed on the middle-shallow cover layer by using stratum horizons controlled by the earthquake and the drilling, and a fine geoelectric structure of the middle-shallow cover layer and a deep free inversion geoelectric structure are obtained;

[0016] S5, an initial geology-geophysics structure model of a profile is established by interpretation according to the second resistivity inversion result and combined with deep structure information reflected by the gravity anomaly, and a gravity-time-frequency electromagnetic-seismic profile joint inversion is carried out by using the stratum rock physical property characteristics and the Bouguer gravity anomaly data to determine a deep target layer top and bottom interface geology structure model;

[0017] S6, an initial horizon geology structure model of a deep target layer is constructed according to the deep target layer top and bottom interface geology structure model, an initial resistivity model of the deep target layer and underlying basement stratum is constructed according to the deep free inversion geoelectric structure, a third resistivity inversion is performed on the deep target layer, and a fine inversion high-resolution resistivity structure profile of the deep target layer is obtained;

[0018] S7, a geological interpretation is performed on the fine inversion high-resolution resistivity structure profile of the deep target layer to study the geological structure and stratum rock property of the deep target layer.

[0019] As a limitation, the step S1 comprises the following steps performed in sequence:

[0020] S11, time-frequency electromagnetic lines and gravity collection lines are laid in the study area and coincide with the seismic lines;

[0021] S12, carry out time-frequency electromagnetic target layer intensive acquisition and gravity profile or area acquisition;

[0022] In the time-frequency electromagnetic target layer intensive acquisition process, first, the frequency response range of the deep target layer is determined through well-to-seismic simulation, a reasonable excitation cycle window is determined, and then the frequency points are collected for the target layer to expand the data collection information;

[0023] S13, according to the target layer intensive acquisition of step S12, time-frequency electromagnetic acquisition data of the measuring point is obtained.

[0024] As a further limitation, step S4 is performed in the following step sequence:

[0025] S41, the shallow layer position with clear reflection on the seismic profile is interpreted, and the shallow layer caprock geological layer model is constructed;

[0026] S42, according to the lithology physical property characteristics of the study area and the macroscopic geoelectric model obtained in step S3, the initial resistivity value of each layer of the shallow layer caprock geological layer is given, and the shallow layer caprock geological-geophysical structure model is established; at the same time, the initial resistivity inversion profile of the deep layer is constructed according to the electrical structure obtained by the first resistivity inversion in step S3, and the deep layer initial geoelectric model is obtained;

[0027] S43, using the simulated annealing inversion method, the shallow layer geoelectric structure is inversed according to the shallow layer caprock geological-geophysical structure model, and the deep layer geoelectric structure is inversed freely according to the deep layer initial geoelectric model, the second resistivity inversion is completed, and the second resistivity inversion profile is obtained, thereby obtaining the fine geoelectric structure of the shallow layer caprock and the free inversion geoelectric structure of the deep layer.

[0028] As a further limitation, step S5 is performed in the following step sequence:

[0029] S51, the electrical layer and abnormal body of the electrical structure of the second resistivity inversion profile are geologically interpreted, and the deep structure information reflected by the gravity anomaly is combined to establish a profile initial geological structure model for gravity-time-frequency electromagnetic-seismic profile joint inversion;

[0030] S52, on the one hand, according to the statistical analysis results of the lithology physical property characteristics of the stratum obtained in step S1, the electrical interpretation layer and abnormal body in the initial geological structure model of the profile are filled with corresponding density parameter values, and the initial profile geological-geophysical model for gravity-time-frequency electromagnetic-seismic profile joint inversion is obtained;

[0031] On the other hand, the Bouguer gravity anomaly data obtained in step S2 is processed to obtain the measured residual gravity anomaly curve of the profile;

[0032] S53, using GeoGME processing interpretation software platform, developing gravity-time-frequency electromagnetic-seismic profile joint inversion;

[0033] During inversion, the geological horizon of each set of strata overlying the deep target layer with clear seismic reflection is fixed, the burial depth of the top and bottom interfaces of the deep target layer with unclear seismic reflection and the position of the fault are adjusted and corrected, and the electrical interpretation horizon and the density parameter value of the abnormal body filling are adjusted within the allowable range of the rock physical property characteristics of the strata in the study area;

[0034] According to the initial profile geological-geophysical model, the gravity anomaly curve is calculated, the calculated gravity anomaly curve is fitted with the measured residual gravity anomaly curve of the profile, according to the fitting condition, the initial profile geological-geophysical model is continuously adjusted and corrected through human-computer interaction, when the calculated gravity anomaly curve is best fitted with the measured residual gravity anomaly curve of the profile and the preset fitting difference is met, the inversion calculation is stopped and the result is output, that is, the deep target layer geological-geophysical profile structure model is obtained, and finally the deep target layer top interface and bottom interface geological structure model is determined through interpretation.

[0035] As a further limitation, the step S6 includes the following process:

[0036] S61, on the one hand, according to the fine geoelectric structure of the shallow cover layer obtained in step S4 and the deep free inversion geoelectric structure, the resistivity variation distribution range of the deep target layer is given;

[0037] On the other hand, according to the deep target layer top interface and bottom interface geological structure model obtained in step S5, the target layer top interface and bottom interface burial depth data are given;

[0038] Combined with the given resistivity variation distribution range of the deep target layer and the target layer top interface and bottom interface burial depth data, the initial geoelectric model of the deep target layer is constructed;

[0039] S62, using the time-frequency electromagnetic acquisition data obtained in step S1, the inversion layer number and iteration number of the deep target layer are refined and increased, and the initial layer thickness and resistivity parameter of each layer are given, and the simulated annealing constrained inversion method is used to carry out focused fine inversion for the deep target layer; during the inversion process, the geoelectric structure of the shallow cover layer is controlled, the amplitude and phase response data curve of the initial geoelectric model is calculated by forward calculation, and compared with the measured data, the fitting error is calculated, through human-computer interaction, the target layer model parameter and the iteration number are continuously modified, when the fitting error reaches the set error standard, the calculation is stopped, the third inversion calculation of the deep target layer resistivity is completed, the inversion result is output, and the fine inversion high-resolution resistivity structure profile of the deep target layer is obtained;

[0040] The measured data refers to the amplitude and phase data curve of the field measurement point.

[0041] The device comprises a survey line, a collection module, a preprocessing module, a time-frequency electromagnetic conventional free inversion module, a time-frequency electromagnetic middle-shallow cover layer constrained inversion module, a gravity-time-frequency electromagnetic-seismic profile joint inversion module, a time-frequency electromagnetic deep target layer fine inversion module, and a deep target layer geological structure and stratum rock attribute determination module.

[0042] The survey line comprises a time-frequency electromagnetic survey line for carrying out time-frequency electromagnetic target layer intensive collection and a gravity collection survey line for carrying out gravity profile or area collection.

[0043] The collection module is used for carrying out time-frequency electromagnetic target layer intensive collection and gravity profile or area collection in cooperation with the time-frequency electromagnetic survey line and the gravity collection survey line, and is used for statistically analyzing stratum rock physical property data of a research area to obtain time-frequency electromagnetic collection data, gravity collection data and stratum rock physical property characteristics of a survey point.

[0044] The preprocessing module is used for preprocessing the time-frequency electromagnetic collection data of the survey point to obtain amplitude and phase data of the survey point, and is used for preprocessing the gravity collection data to obtain Bouguer gravity anomaly data.

[0045] The time-frequency electromagnetic conventional free inversion module is used for carrying out first resistivity inversion to obtain an initial resistivity inversion profile in a depth domain and further obtain a macroscopic geoelectric model.

[0046] The time-frequency electromagnetic middle-shallow cover layer constrained inversion module is used for carrying out second resistivity inversion to obtain a middle-shallow cover layer fine geoelectric structure and a deep free inversion geoelectric structure.

[0047] The gravity-time-frequency electromagnetic-seismic profile joint inversion module is used for carrying out gravity-time-frequency electromagnetic-seismic profile joint inversion to determine a deep target layer top and bottom interface geological structure model.

[0048] The time-frequency electromagnetic deep target layer fine inversion module is used for carrying out third resistivity inversion to obtain a deep target layer fine inversion high-resolution resistivity structure profile.

[0049] The deep target layer geological structure and stratum rock attribute determination module is used for geologically interpreting the deep target layer fine inversion high-resolution resistivity structure profile to research deep target layer geological structure and stratum rock attributes.

[0050] A computer readable storage medium, wherein a computer program is stored in the computer readable storage medium, and the computer program is used for implementing the deep target time-frequency electromagnetic constrained inversion interpretation method when executed by a processor.

[0051] Compared with the prior art, the technical progress achieved by the application lies in that:

[0052] (1) the application is based on the free inversion of the electrical path component data, and proposes a method of time-frequency electromagnetic multi-element joint modeling constraint inversion interpretation for deep target layer, that is, according to the free inversion result and the deep structure information reflected by gravity anomaly, an initial geological model of deep layer is established, the shallow cover layer is controlled and constrained according to the seismic and drilling data, fine inversion is carried out for the deep target layer, various constraint mechanisms are established in the inversion process through multi-element modeling, the 'S' equivalent effect is eliminated, the multi-solution and uncertainty are effectively reduced, and the electrical resolution of the deep target layer is obviously improved, which provides rich and reliable fine electrical stratification abnormal information for the interpretation of deep basin structure and stratum rock property;

[0053] (2) the application adopts the simulated annealing constraint inversion method for the second resistivity inversion based on well-seismic control, the inversion resolution of the electrical structure of the shallow cover layer is improved through the shallow well-seismic modeling constraint inversion, so that the accuracy of the deep free inversion geoelectric structure is also improved;

[0054] (3) the application determines the depth of the top and bottom interfaces of the deep target layer through gravity-time-frequency electromagnetic-seismic profile joint inversion, can provide a reliable geological structure geometric model for the focused fine inversion of the deep target layer, realizes multi-information joint inversion interpretation in the same system platform, effectively reduces the multi-solution, and improves the inversion accuracy;

[0055] (4) in the simulated annealing constraint inversion process of the time-frequency electromagnetic, the multi-element constraint control mechanism of the geological-geophysical model is established, the focused fine inversion is carried out for the deep target layer, the 'S' equivalent effect existing in the traditional electromagnetic inversion is overcome, and the electrical resolution of the deep target layer is improved; the specific embodiment is as follows: first, the geoelectric structure of the overlying layer of the target layer, the resistivity parameters of the target layer and the underlying basement are obtained and fixed through the simulated annealing constraint inversion controlled by the shallow well-seismic; second, the geological structure model of the top interface and bottom interface depth of the target layer is established through gravity-time-frequency electromagnetic-seismic joint profile inversion; third, the data information of the deep target layer is strengthened through the high-density frequency point acquisition of the time-frequency electromagnetic, the number of inversion layers and iteration times of the target layer are refined, and the control of the inversion process of the target layer is strengthened; through the above measures, the electrical stratification macroscopic problem caused by the 'S' equivalent effect existing in the traditional electromagnetic inversion is overcome, the electrical inversion resolution is effectively improved, and the technical difficulty of restricting the low resolution of electromagnetic deep exploration is solved.

[0056] In conclusion, the present application solves the geological problem that the electrical layer structure is relatively macro and difficult to be interpreted in detail due to the S equivalent effect of the conventional electromagnetic inversion method, effectively improves the time-frequency electromagnetic deep inversion resolution, provides fine and reliable electrical anomaly information for the geological structure and stratum rock property research of the deep target layer of the basin, breaks through the technical bottleneck of the low resolution of the conventional electromagnetic deep exploration, and improves the precision of the deep exploration result. BRIEF DESCRIPTION OF DRAWINGS

[0057] The accompanying drawings are included to provide a further understanding of the present application, and constitute a part of the specification, illustrate the present application and explain the principles of the present application, and do not constitute a limitation of the present application.

[0058] In the drawings:

[0059] Figure 1 is a flow chart of the present application embodiment 1;

[0060] Figure 2 is a residual gravity anomaly and time-frequency electromagnetic survey line layout diagram of the NQH area in the present application embodiment 1;

[0061] Figure 3 is a first free inversion resistivity profile diagram of the time-frequency electromagnetic conventional Occam method of the NQH area in the present application embodiment 1;

[0062] Figure 4 is a second inversion resistivity profile and initial geological interpretation model diagram of the time-frequency electromagnetic based on the shallow well seismic control using the simulated annealing constrained inversion method of the NQH area in the present application embodiment 1;

[0063] Figure 5 is a combined inversion interpretation profile diagram of the time-frequency electromagnetic survey line gravity-time-frequency electromagnetic-seismic profile of the NQH area in the present application embodiment 1;

[0064] Figure 6 is a deep target layer focusing fine inversion schematic diagram of the time-frequency electromagnetic of the NQH area in the present application embodiment 1;

[0065] Figure 6 (a) is an initial model schematic diagram of the target layer focusing fine inversion in the present application embodiment 1;

[0066] Figure 6 (b) is a result schematic diagram of the target layer focusing fine inversion in the present application embodiment 1;

[0067] Figure 7 is a third focusing fine inversion resistivity profile and stratum rock property interpretation schematic diagram of the time-frequency electromagnetic using the simulated annealing constrained inversion method for the deep target layer of the NQH area in the present application embodiment 1. DETAILED DESCRIPTION

[0068] The preferred embodiments of the present invention will now be described with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0069] Example 1: A Time-Frequency Electromagnetic Constraint Inversion Interpretation Method for Deep Targets

[0070] Taking a basin in western my country designated NQH as an example, to determine the distribution of favorable hydrocarbon-generating depressions and volcanic reservoirs in the deep Carboniferous system, high-precision 1:50,000 gravity area measurements and time-frequency electromagnetic backbone profile measurements were conducted. The profile locations are as follows: Figure 2 As shown, the time-frequency electromagnetic profile and the two-dimensional seismic survey line coincide. At the same time, surface outcrop physical property measurements were carried out, and stratigraphic and rock physical property data such as density logging and electrical logging were collected and sorted out. The shallow reflections in the seismic data within the basin are clear and of good quality, but the deep Carboniferous igneous rocks are well-developed, and the data quality is poor.

[0071] The method provided in this embodiment is used to conduct time-frequency electromagnetic constraint inversion interpretation of deep targets in the NQH region of a basin in western my country. Figure 1 As shown, the method includes performing steps S1-S5 sequentially.

[0072] S1, such as Figure 2 As shown, time-frequency electromagnetic (TFEM) and gravity acquisition lines were deployed within the basin, coinciding with seismic survey lines. TFEM backbone profile measurements and 1:50,000 high-precision gravity area measurements were conducted. Intensified TFEM acquisition of the deep Carboniferous target layer was carried out, and the stratigraphic and rock property data of the study area were statistically analyzed to obtain TFEM acquisition data, gravity acquisition data, and stratigraphic and rock property characteristics of the study area. During this process, the excitation period window and acquisition frequency of the deep Carboniferous target layer were determined based on well-seismic simulation. Intensified and densified acquisition of the Carboniferous target layer was then performed to obtain TFEM high-density frequency point acquisition data information of the deep Carboniferous target layer.

[0073] In this step, during the enhanced acquisition of time-frequency electromagnetic data of the target layer, the frequency response range of the deep target layer is first determined through well-seismic simulation, and a reasonable excitation period window is established. Then, the acquisition frequency points are densified for the target layer to expand the data acquisition capacity. Based on the enhanced acquisition of the target layer, the time-frequency electromagnetic acquisition data of the measurement points are obtained.

[0074] Specifically, in this step, for the depth range of 2.5-5.5 km of the target layer of the Carboniferous System in the study area, a geoelectric model is established according to seismic and electrical logging data, and the excitation cycle window of the deep target layer is determined to be 0.10-1.05 Hz through forward simulation. Within the above excitation cycle window, the frequency points are encrypted from the normal 10 to 36, and the excitation frequency points are 3.6 times of the original, realizing high-density sampling in the deep target layer. The density, magnetic susceptibility and resistivity physical property distribution characteristics of each formation of the Tertiary System (N+E), Mesozoic (K, J, T), Upper Paleozoic (P, C, D) and igneous rock are analyzed by fully utilizing the measured physical property data of the strata rock in the study area and the surrounding outcrop, density logging and electrical logging.

[0075] S2, the time-frequency electromagnetic acquisition data of the measuring point are preprocessed to obtain time series data, and then the amplitude and phase data of each measuring point are obtained through Fourier transform; the gravity acquisition data of the measuring point are preprocessed to obtain the Bouguer gravity anomaly data of each measuring point;

[0076] The preprocessing process in this step includes denoising, system normalization and static displacement correction.

[0077] The denoising content includes high-power multi-cycle stacking, background noise elimination and fixed cycle interference notch; the system normalization is to eliminate the influence of device coefficients and current emission source current through deconvolution processing; in the static displacement correction process, the phase data not affected by the static displacement and the track information without the static displacement are referenced, and on this basis, the spatial filtering technology is further applied to eliminate the residual static displacement.

[0078] S3, the amplitude and phase data of each measuring point are used to perform full-depth resistivity free inversion by using a conventional free inversion method, to complete the first resistivity inversion, obtain an initial resistivity inversion profile in the depth domain, and further obtain a macroscopic geoelectric model. As shown in Figure 3 the initial resistivity inversion profile in the depth domain is obtained, and the macroscopic profile geoelectric structure of the region above the depth of 5 km is shown in the figure. The conventional free inversion method in this step is the Occam inversion method, and other conventional free inversion methods can also be used in actual operation.

[0079] S4, an initial resistivity model of the shallow cover layer is constructed according to the macroscopic geoelectric model obtained in step S3, the layer position of the shallow cover layer is controlled by using seismic and drilling, the simulated annealing constrained inversion method is used for the second resistivity inversion of the shallow cover layer, and the fine geoelectric structure of the shallow cover layer and the deep free inversion geoelectric structure are obtained, as shown in Figure 4 the fine geoelectric structure of the shallow N+E, T, J and K cover layer and the deep target layer upper Carboniferous (C2) free inversion geoelectric structure are obtained.

[0080] Specifically, step S4 is performed according to the following step sequence:

[0081] S41, through well calibration, the N+E, T, J and K sets of seismic reflection clear horizons in the middle and shallow layers are interpreted, and a middle and shallow layer caprock geological horizon model is constructed based on the seismic interpretation horizons;

[0082] S42, according to the statistical formation rock physical property characteristics in step S1 and the macroscopic geoelectric model obtained in step S3, an initial resistivity value is given to each layer of the middle and shallow layer caprock geological horizon, and a middle and shallow layer caprock geological-geophysical structure model is established for time-frequency electromagnetic-well seismic joint inversion; meanwhile, the electrical structure of the initial resistivity inversion profile in the depth domain obtained by the first resistivity inversion in step S3 is used to interpret the part of the deep reflection unclear in the seismic data, and an initial geoelectric model of the Carboniferous (C2) in the deep target layer is constructed by using the preliminary interpretation result;

[0083] S43, a simulated annealing inversion method is used to constrain the inversion of the geoelectric structure of the N+E, T, J and K horizons in the middle and shallow layers according to the middle and shallow layer caprock geological-geophysical structure model, and the geoelectric structure of the Carboniferous (C2) in the deep target layer is freely inverted by using the deep initial geoelectric model, the second resistivity inversion is completed, and the second resistivity inversion profile is obtained, thereby obtaining the fine geoelectric structure of the middle and shallow layer caprock and the free inversion geoelectric structure of the deep layer. The results are shown in Figure 4 , and Figure 3 Compared with the middle and shallow layer caprock N+E, T, J and K horizon geoelectric structure, the resolution of the middle and shallow layer caprock N+E, T, J and K horizon geoelectric structure is obviously improved.

[0084] S5, according to the second resistivity inversion result and in combination with the deep structure information reflected by the gravity anomaly, an initial geological-geophysical structure model of the profile is established by interpretation, the formation rock physical property characteristics and the Bouguer gravity anomaly data are used to carry out gravity-time-frequency electromagnetic-seismic profile joint inversion, and the geological structure model of the top and bottom interfaces of the Carboniferous (C2) in the deep target layer is determined.

[0085] Step S5 is performed according to the following step sequence:

[0086] S51, the electrical horizons and abnormal bodies of the electrical structure of the second resistivity inversion profile are geologically interpreted, and in combination with the deep structure information reflected by the gravity anomaly, an initial geological structure model of the profile is established for gravity-time-frequency electromagnetic-seismic profile joint inversion;

[0087] S52, on the one hand, according to the statistical analysis result of the formation rock physical property characteristics obtained in step S1, the corresponding density parameter value is filled in the electrical interpretation horizons and abnormal bodies in the initial geological structure model of the profile, and an initial profile geological-geophysical model for gravity-time-frequency electromagnetic-seismic profile joint inversion is obtained;

[0088] On the other hand, the residual gravity anomaly curve of the profile is obtained by processing the Bouguer gravity anomaly data obtained in step S2.

[0089] S53, using a GeoGME processing interpretation software platform, carrying out gravity-time-frequency electromagnetic-seismic profile joint inversion

[0090] During inversion, the geological horizons of each set of cover layer strata of N+E, T, J and K overlying the Carboniferous system (C2) of the deep target layer with clear seismic reflection are fixed, the burial depth of the top and bottom interfaces of the Carboniferous system (C2) of the deep target layer with unclear seismic reflection is adjusted and corrected, and the position of the fault is adjusted and corrected, and meanwhile, within the allowable range of the rock physical property characteristics of the strata in the study area, the electrical interpretation horizons and the density parameter values of the anomaly body filling are appropriately adjusted;

[0091] According to the initial profile geology-geophysical model, the gravity anomaly curve is calculated, the calculated gravity anomaly curve is fitted with the measured residual gravity anomaly curve, according to the fitting condition, the initial profile geology-geophysical model is continuously adjusted and corrected through human-computer interaction, when the calculated gravity anomaly curve and the measured residual gravity anomaly curve reach the best fitting, and the preset fitting difference is satisfied, the inversion calculation is stopped, and the result is output, that is, the geology-geophysical profile structure model of the Carboniferous system (C2) of the deep target layer is obtained, and finally the top interface and bottom interface geology structure model of the Carboniferous system (C2) of the target layer is determined through interpretation, and the obtained result is as shown in Figure 5 , wherein D is the density, and the unit is g / cm 3 It can be seen that the top and bottom interface geology structure model of the Carboniferous system (C2) of the deep target layer is determined through joint inversion and interpretation. In this embodiment, the best fitting refers to that the fitting difference is less than 1%.

[0092] S6, the simulated annealing constrained inversion method is used for the third resistivity inversion of the deep target layer, and a fine inversion high-resolution resistivity structure profile of the deep target layer is obtained.

[0093] Step S6 includes the following processes:

[0094] S61, on the one hand, according to the fine geoelectric structure of the shallow cover layer and the deep free inversion geoelectric structure obtained in step S4, an initial resistivity model of the deep target layer and the underlying basement strata is constructed, the resistivity variation distribution range of the Carboniferous system (C2) of the target layer is given, and the geoelectric structure of the shallow N+E, T, J and K cover layer is controlled and fixed;

[0095] On the other hand, according to the top interface and bottom interface geology structure model of the Carboniferous system (C2) of the deep target layer obtained in step S5, the top interface and bottom interface burial depth data of the Carboniferous system (C2) of the target layer are given;

[0096] Combined with the resistivity variation distribution range of the given deep target layer and the top and bottom interface depth data of the target layer, an initial geoelectric model of the deep target layer is constructed;

[0097] S62, using the time-frequency electromagnetic acquisition data obtained in step S1, the number of inversion layers and the number of iterations of the deep target layer are refined and increased, and the initial layer thickness and resistivity parameters of each layer are given, and the simulated annealing constrained inversion method is used to carry out focused fine inversion on the Carboniferous system (C2) of the deep target layer. During the inversion process, the geoelectric structure of the fixed shallow cover layer is controlled, the amplitude and phase response data curves of the initial geoelectric model are calculated, and the measured data are compared to calculate the fitting error. Through human-computer interaction, the model parameters of the target layer and the number of iterations are constantly modified. When the fitting error reaches the set error standard, the calculation is stopped, the third inversion calculation of the resistivity of the Carboniferous system (C2) of the deep target layer is completed, and the inversion result is output to obtain the fine inversion high-resolution resistivity structure profile of the deep target layer, as shown in Figure 7 The fitting error is less than 1% in this embodiment, which is considered to meet the set error standard. The measured data refers to the amplitude and phase data curves of the measured points in the field.

[0098] During the inversion process, the geoelectric structure of the fixed shallow cover layer is controlled, and the number of layers of the initial model of the deep target layer is refined and increased, as shown in Figure 6 a, in this embodiment, the number of layers of the initial model is increased from 12 to 24, and the number of iterations of the inversion is constantly increased, from 30 to 50 in this embodiment. According to the free inversion result, the resistivity distribution range of the deep target layer and the underlying basement stratum is determined, the fitting error is gradually reduced through multiple iterations, and the fitting error is less than 1% to meet the standard requirement, and the inversion result is obtained as shown in Figure 6 b and Figure 7 . Figure 7 and Figure 3 , Figure 4 It can be found from the comparison that the longitudinal electrical resolution of the deep target layer is obviously improved, and the internal structure of the Carboniferous system (C2) of the target layer is more clearly reflected.

[0099] The result obtained in step S6 will be used for the interpretation of the geological structure and the rock properties of the Carboniferous system (C2) of the deep target layer.

[0100] S7, the fine inversion high-resolution resistivity structure profile of the Carboniferous system (C2) of the deep target layer is geologically interpreted to study the geological structure and the rock properties of the deep target layer. Specifically, on the fine inversion resistivity structure profile of the target layer obtained in step 6, the stratigraphic rock physical characteristics are combined with the statistics in step 1 to interpret the fractures, electrical layers and electrical anomaly bodies, and determine the geological structure and the rock properties of the Carboniferous system (C2) of the deep target layer. The results are shown in Figure 7 .

[0101] Embodiment 2: A deep target time-frequency electromagnetic constraint inversion interpretation device

[0102] The embodiment is used to implement the embodiment 1, which comprises a survey line, a collection module, a pretreatment module, a time-frequency electromagnetic conventional free inversion module, a time-frequency electromagnetic middle-shallow cover constraint inversion module, a gravity-time-frequency electromagnetic-seismic profile joint inversion module, a time-frequency electromagnetic deep target layer fine inversion module, and a deep target layer geological structure and formation rock attribute determination module.

[0103] The survey line comprises a time-frequency electromagnetic survey line for carrying out time-frequency electromagnetic target layer intensive collection and a gravity collection survey line for carrying out gravity profile or area collection.

[0104] The collection module is used to carry out time-frequency electromagnetic target layer intensive collection and gravity profile or area collection in cooperation with the time-frequency electromagnetic survey line and the gravity collection survey line, and to statistically analyze formation rock physical property data of the research area to obtain time-frequency electromagnetic collection data, gravity collection data and formation rock physical property characteristics of the survey point.

[0105] The pretreatment module is used to pretreat the time-frequency electromagnetic collection data of the survey point to obtain amplitude and phase data of the survey point, and to pretreat the gravity collection data to obtain Bouguer gravity anomaly data.

[0106] The time-frequency electromagnetic conventional free inversion module is used to carry out first resistivity inversion to obtain an initial resistivity inversion profile in the depth domain and further obtain a macroscopic geoelectric model.

[0107] The time-frequency electromagnetic middle-shallow cover constraint inversion module is used to carry out second resistivity inversion to obtain a middle-shallow cover fine geoelectric structure and a deep free inversion geoelectric structure.

[0108] The gravity-time-frequency electromagnetic-seismic profile joint inversion module is used to carry out gravity-time-frequency electromagnetic-seismic profile joint inversion to determine a deep target layer top and bottom interface geological structure model.

[0109] The time-frequency electromagnetic deep target layer fine inversion module is used to carry out third resistivity inversion to obtain a deep target layer fine inversion high-resolution resistivity structure profile.

[0110] The deep target layer geological structure and formation rock attribute determination module is used to geologically interpret the deep target layer fine inversion high-resolution resistivity structure profile and study deep target layer geological structure and formation rock attribute.

[0111] Embodiment 3: A computer readable storage medium

[0112] The computer readable storage medium in the embodiment stores a computer program, and the computer program is used to implement the deep target time-frequency electromagnetic constraint inversion interpretation method in the embodiment when executed by the processor.

[0113] The computer readable storage medium can be a computer storage medium or a communication medium. The communication medium includes any medium that facilitates the transfer of a computer program from one place to another. The computer storage medium can be any available medium that can be accessed by a general or special purpose computer. For example, the computer readable storage medium is coupled to the processor, so that the processor can read information from the computer readable storage medium and write information to the computer readable storage medium. Of course, the computer readable storage medium can also be an integral part of the processor. The processor and the computer readable storage medium can be located in an application specific integrated circuit (ASIC). In addition, the ASIC can be located in a user equipment. Of course, the processor and the computer readable storage medium can also exist as discrete components in a communication device. Specifically, the computer readable storage medium can be realized by any type of volatile or non-volatile storage devices or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk or optical disk. The storage medium can be any available medium that can be accessed by a general or special purpose computer.

Claims

1. A deep target time-frequency electromagnetic constraint inversion interpretation method, comprising the following steps performed in sequence, S1. Time-frequency electromagnetic acquisition and gravity acquisition are carried out in the study area, and the stratum rock physical property data of the study area are statistically analyzed to obtain time-frequency electromagnetic acquisition data, gravity acquisition data and stratum rock physical property characteristics of the measuring points; S2. The time-frequency electromagnetic acquisition data of the measuring points are preprocessed to obtain amplitude and phase data of each measuring point, and the gravity acquisition data of the measuring points are preprocessed to obtain Bouguer gravity anomaly data of each measuring point; S3. The amplitude and phase data of each measuring point are used to perform first resistivity inversion to obtain an initial resistivity inversion profile in the depth domain and further obtain a macroscopic geoelectric model; characterized in that, after step S3, the following steps are performed in sequence: S4. An initial resistivity model of the middle-shallow layer caprock is constructed according to the macroscopic geoelectric model, the middle-shallow layer stratum horizon is controlled by using the seismic and drilling, second resistivity inversion is performed for the middle-shallow layer caprock to obtain a fine geoelectric structure of the middle-shallow layer caprock and a deep free inversion geoelectric structure; S5. An initial geology-geophysics structure model of the profile is established by interpretation according to the second resistivity inversion result and combined with the deep structure information reflected by the gravity anomaly, the stratum rock physical property characteristics and the Bouguer gravity anomaly data are used to perform gravity-time-frequency electromagnetic-seismic profile joint inversion to determine a geological structure model of the top and bottom interfaces of the deep target layer; S6. An initial horizon geological structure model of the deep target layer is constructed according to the geological structure model of the top and bottom interfaces of the deep target layer, an initial resistivity model of the deep target layer and the underlying basement stratum is constructed according to the deep free inversion geoelectric structure, third resistivity inversion is performed for the deep target layer to obtain a fine inversion high-resolution resistivity structure profile of the deep target layer; S7. Geological interpretation is performed on the fine inversion high-resolution resistivity structure profile of the deep target layer to study the geological structure and stratum rock property of the deep target layer.

2. The deep target time-frequency electromagnetic constrained inversion interpretation method according to claim 1, characterized in that, The step S1 comprises the following steps performed in sequence: S11. Time-frequency electromagnetic measuring lines and gravity acquisition measuring lines are laid in the study area coinciding with the seismic measuring lines; S12. Time-frequency electromagnetic target layer intensive acquisition and gravity profile or area acquisition are carried out; in the time-frequency electromagnetic target layer intensive acquisition process, first, the frequency response range of the deep target layer is determined through well-seismic simulation, a reasonable excitation cycle window is determined, then the frequency points are densified for the target layer, and the data acquisition information is expanded; S13. Time-frequency electromagnetic acquisition data of the measuring points are obtained according to the target layer intensive acquisition of step S12.

3. The deep target time-frequency electromagnetic constrained inversion interpretation method according to claim 2, characterized in that, Step S4 is performed in the following step sequence: S41. The middle-shallow layer horizon with clear reflection on the seismic profile is interpreted to construct a middle-shallow layer caprock geological horizon model; S42. According to the stratum rock physical property characteristics of the study area and the macroscopic geoelectric model obtained in step S3, an initial resistivity value is given to each layer of the middle-shallow layer caprock geological horizon to establish a middle-shallow layer caprock geology-geophysics structure model; meanwhile, a deep initial geoelectric model is constructed according to the electrical structure of the initial resistivity inversion profile in the depth domain obtained by the first resistivity inversion in step S3; S43, using the simulated annealing inversion method, the shallow cover geological-geophysical structure model is used to constrain the shallow geoelectric structure, and the deep initial geoelectric model is used to freely invert the deep geoelectric structure, the second resistivity inversion is completed, the second resistivity inversion profile is obtained, and the fine geoelectric structure of the shallow cover and the free inversion geoelectric structure of the deep layer are obtained.

4. The deep target time-frequency electromagnetic constrained inversion interpretation method according to claim 3, characterized in that, Step S5 is performed in the following order: S51, the electrical layer and abnormal body of the second resistivity inversion profile are geologically interpreted, and the deep structure information reflected by the gravity anomaly is combined to establish a profile initial geological structure model for gravity-time-frequency electromagnetic-seismic profile joint inversion; S52, on the one hand, according to the statistical analysis result of the stratum rock physical property characteristics obtained in step S1, the density parameter value corresponding to the electrical interpretation layer and abnormal body in the profile initial geological structure model is filled, and the initial profile geological-geophysical model for gravity-time-frequency electromagnetic-seismic profile joint inversion is obtained; On the other hand, the Bouguer gravity anomaly data obtained in step S2 is processed to obtain a profile measured residual gravity anomaly curve; S53, using the GeoGME processing and interpretation software platform, gravity-time-frequency electromagnetic-seismic profile joint inversion is carried out; During inversion, the geological layer of each set of strata overlying the deep target layer with clear seismic reflection is fixed, the depth of the top and bottom interfaces of the deep target layer with unclear seismic reflection and the position of the fault are adjusted and corrected, and the density parameter value filled in each electrical interpretation layer and abnormal body is adjusted within the allowable range of the rock physical property characteristics of the strata in the study area; According to the initial profile geological-geophysical model, the gravity anomaly curve is calculated, the calculated gravity anomaly curve is fitted with the profile measured residual gravity anomaly curve, and according to the fitting condition, the initial profile geological-geophysical model is continuously adjusted and corrected through human-computer interaction. When the calculated gravity anomaly curve and the profile measured residual gravity anomaly curve are best fitted and meet the preset fitting difference, the inversion calculation is stopped, and the result is output, that is, the deep target layer geological-geophysical profile structure model is obtained, and finally the deep target layer top interface and bottom interface geological structure model is determined.

5. The deep target time-frequency electromagnetic constrained inversion interpretation method according to claim 4, characterized in that, The step S6 includes the following processes: S61, on the one hand, according to the fine geoelectric structure of the shallow cover and the free inversion geoelectric structure of the deep layer obtained in step S4, the resistivity variation distribution range of the deep target layer is given; On the other hand, according to the deep target layer top interface and bottom interface geological structure model obtained in step S5, the top interface and bottom interface depth data of the target layer are given; Combined with the given resistivity variation distribution range of the deep target layer and the top interface and bottom interface depth data of the target layer, the initial geoelectric model of the deep target layer is constructed; S62, using the time-frequency electromagnetic acquisition data obtained in step S1, the number of inversion layers and the number of iterations of the deep target layer are refined and increased, and the initial layer thickness and resistivity parameters of each layer are given. The simulated annealing constraint inversion method is used to carry out focused fine inversion for the deep target layer. In the inversion process, the geoelectric structure of the fixed shallow cover layer is controlled, the amplitude and phase response data curves of the initial geoelectric model are calculated by forward calculation, compared with the measured data, the fitting error is calculated, the target layer model parameters and the iteration number are modified through human-computer interaction, and when the fitting error reaches the set error standard, the calculation is stopped, the third inversion calculation of the deep target layer resistivity is completed, and the inversion result is output to obtain the fine inversion high-resolution resistivity structure profile of the deep target layer. The measured data refers to the amplitude and phase data curves of the measured points in the field.

6. A deep target time-frequency electromagnetic constrained inversion interpretation device for implementing the deep target time-frequency electromagnetic constrained inversion interpretation method according to any one of claims 1-5, characterized in that, It comprises: a survey line, a collection module, a preprocessing module, a time-frequency electromagnetic conventional free inversion module, a time-frequency electromagnetic shallow cover layer constraint inversion module, a gravity-time-frequency electromagnetic-seismic profile joint inversion module, a time-frequency electromagnetic deep target layer fine inversion module, and a deep target layer geological structure and stratum rock property determination module; The survey line comprises a time-frequency electromagnetic survey line for carrying out time-frequency electromagnetic target layer intensive collection and a gravity collection survey line for carrying out gravity profile or area collection; The collection module cooperates with the time-frequency electromagnetic survey line and the gravity collection survey line to carry out time-frequency electromagnetic target layer intensive collection and gravity profile or area collection, and statistically analyzes the stratum rock physical property data of the research area to obtain the time-frequency electromagnetic collection data, gravity collection data and stratum rock physical characteristics of the measured points; The preprocessing module pre-processes the time-frequency electromagnetic collection data of the measured points to obtain the amplitude and phase data of the measured points, and pre-processes the gravity collection data to obtain the Bouguer gravity anomaly data; The time-frequency electromagnetic conventional free inversion module is used to carry out the first resistivity inversion, obtain the initial resistivity inversion profile in the depth domain, and further obtain the macroscopic geoelectric model; The time-frequency electromagnetic shallow cover layer constraint inversion module is used to carry out the second resistivity inversion to obtain the fine geoelectric structure of the shallow cover layer and the deep free inversion geoelectric structure; The gravity-time-frequency electromagnetic-seismic profile joint inversion module is used to carry out gravity-time-frequency electromagnetic-seismic profile joint inversion to determine the geological structure model of the top and bottom interfaces of the deep target layer; The time-frequency electromagnetic deep target layer fine inversion module is used to carry out the third resistivity inversion to obtain the fine inversion high-resolution resistivity structure profile of the deep target layer; The deep target layer geological structure and stratum rock property determination module geologically interprets the fine inversion high-resolution resistivity structure profile of the deep target layer to study the geological structure and stratum rock property of the deep target layer.

7. A computer readable storage medium characterized in that, The computer program is stored in the computer readable storage medium and is executed by the processor to implement the deep target time-frequency electromagnetic constraint inversion interpretation method according to any one of claims 1-5.

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