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

Abstract

The invention belongs to the technical field of electromagnetic method exploration, discloses a deep target time-frequency electromagnetic constraint inversion interpretation method and device and a storage medium, and provides a time-frequency electromagnetic multivariate joint modeling constraint inversion interpretation method for a deep target layer on the basis of electric channel component data free inversion. The method comprises the following steps: establishing a deep initial geologic model according to a resistivity free inversion result and deep structure information reflected by gravity anomaly, controlling a shallow cover layer geoelectric structure in constraint according to earthquake and drilling data, performing fine inversion on a deep target layer, and establishing various constraint mechanisms through multivariate modeling in the inversion process. According to the method, the defect of an S equivalent effect in the prior art is overcome, multiplicity and uncertainty are reduced, the resolution of a deep target layer is obviously improved through an inversion result, and rich and reliable fine electrical property layering abnormal information is provided for interpretation and research of a deep basin structure and stratum rock attributes. The method is suitable for interpretation and research of deep basin structures and stratum rock attributes.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic exploration, and relates to a time-frequency electromagnetic constrained inversion and interpretation method, device, and storage medium for deep targets. Background Art

[0002] The deep layer of the basin contains rich energy resources such as oil, gas, and geothermal energy. It is an important new series and field for succeeding oil and gas reserves, and also an important series and field for searching for oil, gas, and geothermal resources.

[0003] The quality of seismic data in the middle and shallow layers of the basin is generally good. However, due to the long time experienced and many tectonic movements in the deep layer of the basin, it has the characteristics of complex structure and developed igneous rocks. It is often difficult to obtain effective reflection data in seismic exploration. Therefore, it is very difficult to clearly understand the deep basin structure and formation rock properties only relying on seismic data.

[0004] Due to the limitations of single geophysical methods and the non-uniqueness and uncertainty of geophysical inversion results, to implement deep targets in the basin, it is necessary to adopt a method of joint modeling and constrained inversion and interpretation using multiple geophysical data, that is, using seismic data to establish a geological model in the shallow layer. Since the deep layer seismic data is unclear, combined with non-seismic data such as gravity and electromagnetics to jointly establish a deep geological model, and then perform inversion and interpretation to improve the resolution of deep exploration, so as to obtain rich and reliable geophysical information of deep exploration targets.

[0005] Time-frequency electromagnetic method (TFEM) is a new high-power artificial field source electromagnetic exploration method developed in recent years. Compared with traditional natural field source electromagnetic methods such as magnetotelluric sounding (MT) and continuous electromagnetic array profiling (CEMP), it significantly improves the effective detection depth. At present, due to the magnetic track component of the TFEM method being easily interfered by surface conditions, data is usually collected using the electric track component for inversion. However, the existing conventional inversion methods have the problem of "S" equivalent effect, resulting in a relatively macroscopic deep electrical structure layer obtained by free inversion of the electric track component, with low resolution and unclear identification of internal electrical changes, which restricts the identification accuracy of the deep basin structure and formation rock properties and is not conducive to deep target exploration research. Summary of the Invention

[0006] The object of the present invention is to provide a time-frequency electromagnetic constrained inversion and interpretation method for deep targets to break through the technical bottleneck that restricts the low resolution of conventional electromagnetic deep exploration; The second object of the present invention is to provide a time-frequency electromagnetic constrained inversion and interpretation device for deep targets; The third object of the present invention is to provide a storage medium for the time-frequency electromagnetic constrained inversion and interpretation method for deep targets.

[0007] To achieve the above objects, the technical solutions adopted by the present invention are as follows: A deep target time-frequency electromagnetic constraint inversion and interpretation method, comprising the following steps carried out in sequence: S1. Conduct time-frequency electromagnetic acquisition and gravity acquisition work in the study area, statistically analyze the physical properties data of the strata and rocks in the study area, and obtain the time-frequency electromagnetic acquisition data, gravity acquisition data of the measuring points and the physical property characteristics of the strata and rocks; S2. Preprocess the time-frequency electromagnetic acquisition data of the measuring points to obtain the amplitude and phase data of each measuring point, and preprocess the gravity acquisition data of the measuring points to obtain the Bouguer gravity anomaly data of each measuring point; S3. Use the amplitude and phase data of each measuring point to perform the first resistivity inversion, obtain the initial resistivity inversion profile in the depth domain, and further obtain the macroscopic geoelectric model; It is characterized in that after completing step S3, the following steps are carried out in sequence: S4. Construct the initial resistivity model of the middle and shallow cover layers according to the macroscopic geoelectric model, use seismic and drilling to control the middle and shallow stratigraphic horizons, and perform the second resistivity inversion for the middle and shallow cover layers to obtain the fine geoelectric structure of the middle and shallow cover layers and the deep free inversion geoelectric structure; S5. According to the results of the second resistivity inversion and combined with the deep structure information reflected by the gravity anomaly, establish the initial geological-geophysical structure model of the profile through interpretation, and use the physical property characteristics of the strata and rocks and the Bouguer gravity anomaly data to carry out joint inversion of gravity-time-frequency electromagnetic-seismic profiles to determine the geological structure model of the top and bottom interfaces of the deep target layer; S6. Construct the initial horizon geological structure model of the deep target layer according to the geological structure model of the top and bottom interfaces of the deep target layer, construct the initial resistivity model of the deep target layer and the underlying basement strata according to the deep free inversion geoelectric structure, and perform the third resistivity inversion for the deep target layer to obtain the fine inversion high-resolution resistivity structure profile of the deep target layer; S7. Conduct geological interpretation on the fine inversion high-resolution resistivity structure profile of the deep target layer to study the geological structure and formation rock properties of the deep target layer.

[0008] As a limitation, step S1 includes the following steps carried out in sequence: S11. Layout the time-frequency electromagnetic survey line and the gravity acquisition survey line coinciding with the seismic survey line in the study area; S12. Conduct enhanced acquisition of the time-frequency electromagnetic target layer and gravity profile or area acquisition; During the enhanced acquisition of the time-frequency electromagnetic target layer, first determine the frequency response range of the deep target layer through well-seismic simulation, determine a reasonable excitation period window, and then encrypt the acquisition frequency points for the target layer to expand the information acquisition of the data; S13. Obtain the time-frequency electromagnetic acquisition data of the measuring points according to the enhanced acquisition of the target layer in step S12.

[0009] As a further limitation, step S4 is carried out in the following step sequence: S41. Interpret the horizons with clear mid-shallow reflections on the seismic profile and construct a mid-shallow caprock geological horizon model; S42. According to the physical properties of formation rocks in the study area and the macroscopic geoelectric model obtained in step S3, assign an initial resistivity value to each layer of the mid-shallow caprock geological horizon and establish a mid-shallow caprock geological-geophysical structure model; meanwhile, construct a deep initial geoelectric model according to the electrical structure of the initial resistivity inversion profile in the depth domain obtained from the first resistivity inversion in step S3; S43. Adopt the simulated annealing inversion method to inversely calculate the mid-shallow geoelectric structure under the constraint of the mid-shallow caprock geological-geophysical structure model and inversely calculate the deep geoelectric structure freely according to the deep initial geoelectric model, complete the second resistivity inversion, obtain the second resistivity inversion profile, and thus obtain the fine geoelectric structure of the mid-shallow caprock and the freely inverted deep geoelectric structure.

[0010] As a further limitation, step S5 is carried out in the following step sequence: S51. Conduct geological interpretation on the electrical horizons and abnormal bodies in the electrical structure of the second resistivity inversion profile and combine the deep structure information reflected by the gravity anomaly to establish an initial profile geological structure model for joint inversion of gravity-time-frequency electromagnetic-seismic profile; S52. On the one hand, based on the statistical analysis results of the physical properties of formation rocks obtained in step S1, fill in the corresponding density parameter values for the electrical interpretation horizons and abnormal bodies in the initial profile geological structure model to obtain an initial profile geological-geophysical model for joint inversion of gravity-time-frequency electromagnetic-seismic profile; On the other hand, process the Bouguer gravity anomaly data obtained in step S2 to obtain the measured residual gravity anomaly curve of the profile; S53. Use the GeoGME processing and interpretation software platform to carry out joint inversion of gravity-time-frequency electromagnetic-seismic profile; During inversion, fix the geological horizons of each set of strata in the overlying strata of the deep target layer with clear seismic reflections, adjust and correct the burial depths of the top and bottom interfaces and the fault positions of the deep target layer with unclear seismic reflections, and meanwhile adjust the density parameter values filled in each electrical interpretation horizon and abnormal body within the allowable range of the physical properties of formation rocks in the study area; Calculate the gravity anomaly curve according to the initial profile geological-geophysical model, fit the calculated gravity anomaly curve with the measured residual gravity anomaly curve of the profile. According to the fitting situation, continuously adjust and correct the initial profile geological-geophysical model through human-computer interaction. When the calculated gravity anomaly curve and the measured residual gravity anomaly curve of the profile reach the best fit and meet the preset fitting error, stop the inversion calculation and output the result, that is, obtain the geological-geophysical profile structure model of the deep target layer. Finally, determine the geological structure models of the top and bottom interfaces of the deep target layer through interpretation.

[0011] As a further limitation, the step S6 includes the following process: S61. On the one hand, according to the fine geoelectric structure of the middle and shallow cover layers and the deep free inversion geoelectric structure obtained in step S4, give the resistivity change distribution range of the deep target layer; On the other hand, according to the geological structure models of the top and bottom interfaces of the deep target layer obtained in step S5, give the burial depth data of the top and bottom interfaces of the target layer; Combine the given resistivity change distribution range of the deep target layer and the burial depth data of the top and bottom interfaces of the target layer to construct the initial geoelectric model of the deep target layer; S62. Use the time-frequency electromagnetic acquisition data obtained in step S1, refine and increase the inversion layers and iteration times of the deep target layer, and give the initial layer thickness and resistivity parameters of each layer. Use the simulated annealing constrained inversion method to carry out focused fine inversion for the deep target layer. During the inversion process, control and fix the geoelectric structure of the middle and shallow cover layers, forward calculate the amplitude and phase response data curves of the initial geoelectric model, compare with the measured data, calculate the fitting error, and through human-computer interaction, continuously modify the model parameters and iteration times of the target layer. When the fitting error reaches the set error standard, stop the calculation, complete the third inversion calculation of the resistivity of the deep target layer, output the inversion result, and 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 field measured points.

[0012] A deep target time-frequency electromagnetic constrained inversion interpretation device includes: a survey line, an acquisition module, a preprocessing module, a time-frequency electromagnetic conventional free inversion module, a time-frequency electromagnetic middle and 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 formation rock property determination module; The survey line includes a time-frequency electromagnetic survey line for carrying out enhanced acquisition of the time-frequency electromagnetic target layer, and a gravity acquisition survey line for carrying out gravity profile or area acquisition; The acquisition module cooperates with the time-frequency electromagnetic survey line and the gravity acquisition survey line to carry out enhanced acquisition of the time-frequency electromagnetic target layer and gravity profile or area acquisition, and statistically analyzes the physical properties of strata and rocks in the study area to obtain the time-frequency electromagnetic acquisition data, gravity acquisition data of the measuring points and the physical property characteristics of strata and rocks; The preprocessing module preprocesses the time-frequency electromagnetic acquisition data of the measuring points to obtain the amplitude and phase data of the measuring points, and preprocesses the gravity acquisition 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 middle and shallow layer caprock constrained inversion module is used to carry out the second resistivity inversion to obtain the fine geoelectric structure of the middle and shallow layer caprocks and the deep free inversion geoelectric structure; The gravity-time-frequency electromagnetic-seismic profile joint inversion module is used to carry out the 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 formation rock property determination module conducts geological interpretation on the fine inversion high-resolution resistivity structure profile of the deep target layer to study the geological structure and formation rock properties of the deep target layer.

[0013] A computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, it is used to implement the above-mentioned deep target time-frequency electromagnetic constrained inversion and interpretation method.

[0014] Due to the adoption of the above technical solution, compared with the prior art, the technical progress achieved by the present invention is as follows: (1) Based on the free inversion of the electric component data, the present invention proposes a method for time-frequency electromagnetic multi-source joint modeling constrained inversion and interpretation for the deep target layer, that is, based on the free inversion result and the deep structure information reflected by the gravity anomaly, an initial deep geological model is established, the geoelectric structure of the middle and shallow layer caprocks is controlled and constrained according to seismic and drilling data, and fine inversion is carried out for the deep target layer. During the inversion process, various constraint mechanisms are established through multi-source modeling to eliminate the "S" equivalent effect, effectively reducing the non-uniqueness and uncertainty. The inversion result significantly improves the electrical resolution of the deep target layer, providing rich and reliable fine electrical stratification anomaly information for the interpretation and research of the deep basin structure and formation rock properties; (2) The present invention uses the simulated annealing constrained inversion method based on well seismic control to perform the second resistivity inversion. By constraining the inversion through well seismic modeling in the middle and shallow layers, the inversion resolution of the electrical structure of the middle and shallow caprock is improved, thereby also improving the accuracy of the deep free inversion geoelectric structure; (3) The present invention determines the top and bottom interface burial depths of deep target layers through joint inversion of gravity-time-frequency electromagnetic-seismic profiles, which can provide a reliable geological structure geometric model for focused fine inversion of deep target layers, and realizes multi-information joint inversion interpretation on the same system platform, effectively reducing multi-solution and improving inversion accuracy; (4) In the process of time-frequency electromagnetic simulated annealing constrained inversion, the present invention establishes a multi-constraint control mechanism of geological-geophysical model, conducts focused fine inversion for deep target layers, overcomes the "S" equivalent effect existing in traditional electromagnetic inversion, and improves the electrical resolution of deep target layers; it is specifically embodied in the following three aspects: first, through simulated annealing constrained inversion controlled by medium and shallow well seismic, the geoelectric structure of the overburden layer on the target layer, the resistivity parameters of the target layer and the underlying basement are obtained and fixed; second, through gravity-time-frequency electromagnetic-seismic joint profile inversion, the buried depth geological structure model of the top interface and bottom interface of the target layer is established; third, the time-frequency electromagnetic deep target layer is fully utilized to strengthen the high-density frequency point acquisition data information, refine and increase the number of inversion layers and iterations of the target layer, and strengthen the control of the inversion process of the target layer; through the above measures, the problem of macroscopic electrical stratification caused by the "S" equivalent effect existing in traditional electromagnetic inversion is overcome, the electrical inversion resolution is effectively improved, and the technical problem that restricts the low resolution of deep exploration by electromagnetic method is solved.

[0015] In summary, the present invention solves the geological problem that the electrical layer structure is relatively macroscopic and difficult to interpret in fine layers due to the "S" equivalent effect in the traditional electromagnetic inversion method, effectively improves the resolution of deep-layer time-frequency electromagnetic inversion, and provides fine and reliable electrical anomaly information for the study of the geological structure of the deep target layer of the basin and the rock properties of the formation, breaking through the technical bottleneck that restricts the low resolution of deep exploration by conventional electromagnetic methods, and improving the accuracy of deep exploration results. Brief Description of the Figures

[0016] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention.

[0017] In the attached figure: Figure 1 is a flow chart of Example 1 of the present invention; Figure 2 The residual gravity anomaly and time-frequency electromagnetic survey line layout diagram of the NQH area in Example 1 of the present invention; Figure 3 ​This is the resistivity profile diagram of the first free inversion of the time-frequency electromagnetic conventional Occam method in the NQH area in Embodiment 1 of the present invention; Figure 4 This is the resistivity profile diagram of the second inversion and the initial geological interpretation model diagram of the time-frequency electromagnetic method in the NQH area in Embodiment 1 of the present invention, which adopts the simulated annealing constrained inversion method based on the middle and shallow layer well-seismic control; Figure 5 This is the joint inversion and interpretation profile diagram of gravity-time-frequency electromagnetic-seismic profiles of the time-frequency electromagnetic survey line in the NQH area in Embodiment 1 of the present invention; Figure 6 This is the schematic diagram of the focused fine inversion of the deep target layer of the time-frequency electromagnetic method in the NQH area in Embodiment 1 of the present invention; Figure 6 (a) This is the schematic diagram of the initial model of the focused fine inversion of the target layer in Embodiment 1 of the present invention; Figure 6 (b) This is the schematic diagram of the result of the focused fine inversion of the target layer in Embodiment 1 of the present invention; Figure 7 This is the resistivity profile diagram and the schematic diagram of the interpretation of the formation rock properties of the third focused fine inversion of the deep target layer of the time-frequency electromagnetic method in the NQH area in Embodiment 1 of the present invention, which adopts the simulated annealing constrained inversion method. Detailed implementation manners

[0018] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not used to limit the present invention.

[0019] Embodiment 1 A method for constrained inversion and interpretation of deep target time-frequency electromagnetic Taking the area with the code NQH in a certain basin in the western part of China as an example, in order to identify the favorable hydrocarbon-generating sag and volcanic reservoir distribution in the deep Carboniferous system in this area, high-precision gravity area measurement at a scale of 1:50,000 and time-frequency electromagnetic backbone profile measurement were carried out. The profile positions are as Figure 2 shown. The time-frequency electromagnetic profile coincides with the 2D seismic survey line. At the same time, on-site physical property measurements of outcrops were carried out, and formation rock physical property data such as density logging and electric logging were collected and sorted out. In the seismic data in the basin, the shallow reflections are clear and of good quality, but the deep Carboniferous igneous rocks are developed and the data quality is poor.

[0020] The method provided in this embodiment is used to carry out constrained inversion and interpretation of the deep target time-frequency electromagnetic in the NQH area of a certain basin in the western part of China as Figure 1 shown. This method includes successively performing steps S1-S5.

[0021] S1. As Figure 2As shown in the figure, when arranging the time-frequency electromagnetic survey line and the gravity acquisition survey line to coincide with the seismic survey line in the basin, carry out the time-frequency electromagnetic backbone profile measurement and the 1:50,000 high-precision gravity area measurement, conduct the enhanced acquisition of the deep Carboniferous target layer in the time-frequency electromagnetic method, statistically analyze the formation rock physical property data in the study area, and obtain the time-frequency electromagnetic acquisition data, gravity acquisition data of the measuring points and the formation rock physical property characteristics of the study area. In this process, based on well-seismic simulation, determine the excitation period window and acquisition frequency of the deep Carboniferous target layer, and conduct enhanced and dense acquisition for the Carboniferous target layer to obtain the enhanced high-density frequency point acquisition data information of the deep Carboniferous target layer in the time-frequency electromagnetic method.

[0022] In this step, during the enhanced acquisition of the time-frequency electromagnetic target layer, first determine the frequency response range of the deep target layer through well-seismic simulation, determine a reasonable excitation period window, and then encrypt the acquisition frequency points for the target layer to expand the data acquisition information. According to the enhanced acquisition of the target layer, obtain the time-frequency electromagnetic acquisition data of the measuring points.

[0023] Specifically, in this step, for the depth range of the Carboniferous target layer in the study area of 2.5 - 5.5 km, establish a geoelectric model based on seismic and electric logging data, determine the excitation period window of the deep target layer as 0.10 - 1.05 Hz through forward simulation. Within the above excitation period window range, encrypt the excitation acquisition frequency points from the normal 10 to 36, and the excitation frequency points are 3.6 times the original, realizing high-density sampling within the deep target layer. Make full use of the formation rock physical property data such as the actual measurement of the physical properties of outcrops on the ground in the study area and its surrounding areas, density logging, and electric logging, and analyze the density, magnetic susceptibility, and resistivity physical property distribution characteristics of each formation of the Tertiary (N+E), Mesozoic (K, J, T), Upper Paleozoic (P, C, D), and igneous rocks.

[0024] S2. Preprocess the time-frequency electromagnetic acquisition data of the measuring points to obtain time series data, then obtain the amplitude and phase data of each measuring point through Fourier transform, and preprocess the gravity acquisition data of the measuring points to obtain the Bouguer gravity anomaly data of each measuring point; In this step, the preprocessing process includes denoising, system normalization, and static displacement correction.

[0025] Among them, the content of denoising includes high-power multi-period stacking, background noise elimination-based, and fixed-period interference notch filtering; system normalization is to eliminate the influence of the device coefficient and the current of the current emission source through deconvolution processing; during the static displacement correction process, refer to the phase data that is not affected by static displacement and the magnetic track information without static displacement, and further apply spatial filtering technology to eliminate the residual static displacement on this basis.

[0026] S3. Using the amplitude and phase data of each measuring point, perform full-depth resistivity free inversion by means of a conventional free inversion method to complete the first resistivity inversion, obtain the initial resistivity inversion profile in the depth domain, and further obtain the macroscopic geoelectric model. As Figure 3 shown in the obtained initial resistivity inversion profile in the depth domain, the macroscopic profile geoelectric structure above the altitude of -5 km is shown in the figure. The conventional free inversion method in this step is specifically the Occam inversion method, and other conventional free inversion methods can also be used in actual operation.

[0027] S4. Construct the initial resistivity model of the middle and shallow cover layer according to the macroscopic geoelectric model obtained in step S3. Use seismic and drilling to control the middle and shallow strata horizons, and perform the second resistivity inversion for the middle and shallow cover layer by means of the simulated annealing constrained inversion method to obtain the fine geoelectric structure of the middle and shallow cover layer and the deep free inversion geoelectric structure. As Figure 4 shown are the fine geoelectric structures of the middle and shallow N+E, T, J, and K cover layers and the deep free inversion geoelectric structure of the deep target layer, the Upper Carboniferous (C 2 ).

[0028] Specifically, step S4 is carried out in the following order: S41. Through well logging calibration, interpret the horizons of the middle and shallow N+E, T, J, and K sets with clear seismic reflections. Based on this seismic interpretation horizon, construct the geological horizon model of the middle and shallow cover layer; S42. According to the formation rock physical property characteristics statistically obtained in step S1 and the macroscopic geoelectric model obtained in step S3, assign the initial resistivity value to each layer of the geological horizon of the middle and shallow cover layer, and establish the geological-geophysical structure model of the middle and shallow cover layer with time-frequency electromagnetic-well seismic joint constraints; at the same time, use the electrical structure of the initial resistivity inversion profile in the depth domain obtained from the first resistivity inversion in step S3 to interpret the part with unclear deep seismic reflections of the seismic data, and use the preliminary interpretation results to construct the initial geoelectric model of the deep target layer, the Upper Carboniferous (C 2 ); S43. Adopt the simulated annealing inversion method to inversely constrain the geoelectric structures of the middle and shallow N+E, T, J, and K horizons according to the geological-geophysical structure model of the middle and shallow cover layer, and freely inversely the geoelectric structure of the deep target layer, the Upper Carboniferous (C 2 ) with the deep initial geoelectric model to complete the second resistivity inversion, obtain the second resistivity inversion profile, and thus obtain the fine geoelectric structure of the middle and shallow cover layer and the deep free inversion geoelectric structure. The results are as Figure 4 shown, and Figure 3 compared with, the resolution of the geoelectric structures of the middle and shallow N+E, T, J, and K horizons of the cover layer has been significantly improved.

[0029] S5. Based on the results of the second resistivity inversion and combined with the deep structure information reflected by the gravity anomaly, establish an initial geological-geophysical structure model of the profile through interpretation. Utilize the physical property characteristics of formation rocks and Bouguer gravity anomaly data to conduct joint inversion of gravity-time-frequency electromagnetic-seismic profiles, and determine the geological structure models of the top and bottom interfaces of the deep target layer, the Upper Carboniferous (C 2 ).

[0030] Step S5 is carried out in the following order: S51. Conduct geological interpretation on the electrical horizons and abnormal bodies of the electrical structure of the second resistivity inversion profile, and combine with the deep structure information reflected by the gravity anomaly to establish an initial geological structure model of the profile for joint inversion of gravity-time-frequency electromagnetic-seismic profiles; S52. On the one hand, based on the statistical analysis results of the physical property characteristics of formation rocks obtained in step S1, fill the corresponding density parameter values for the electrical interpretation horizons and abnormal bodies in the initial geological structure model of the profile to obtain an initial geological-geophysical model of the profile for joint inversion of gravity-time-frequency electromagnetic-seismic profiles; On the other hand, process the Bouguer gravity anomaly data obtained in step S2 to obtain the measured residual gravity anomaly curve of the profile; S53. Utilize the GeoGME processing and interpretation software platform to conduct joint inversion of gravity-time-frequency electromagnetic-seismic profiles During inversion, fix the geological horizons of the overlying strata N+E, T, J, and K of the Upper Carboniferous (C 2 ) of the deep target layer with clear seismic reflections, and adjust and correct the burial depths of the top and bottom interfaces and the fault positions of the Upper Carboniferous (C 2 ) of the deep target layer with unclear seismic reflections. At the same time, appropriately adjust the density parameter values filled for each electrical interpretation horizon and abnormal body within the range allowed by the physical property characteristics of the formation rocks in the study area; Calculate the gravity anomaly curve according to the initial geological-geophysical model of the profile, fit the calculated gravity anomaly curve with the measured residual gravity anomaly curve. According to the fitting situation, continuously adjust and correct the initial geological-geophysical model of the profile through man-machine interaction. When the calculated gravity anomaly curve and the measured residual gravity anomaly curve reach the best fit and meet the preset fitting error, stop the inversion calculation and output the result, that is, obtain the geological-geophysical profile structure model of the Upper Carboniferous (C 2 ) of the deep target layer. Finally, determine the geological structure models of the top and bottom interfaces of the target layer, the Upper Carboniferous (C 2 ), and the obtained results are as Figure 5 shown. In the figure, D is the density, with the unit of g / cm 3 . It can be seen that the geological structure models of the top and bottom interfaces of the Upper Carboniferous (C 2The top and bottom interface geological structure models of ()). In this embodiment, the best fit means that the fitting error is less than 1%.

[0031] S6. For the deep target layer, use the simulated annealing constrained inversion method to perform the third resistivity inversion to obtain a fine inversion high-resolution resistivity structure profile of the deep target layer.

[0032] Step S6 includes the following processes: S61. On the one hand, based on the fine geoelectric structure of the middle and shallow cover layers and the deep free inversion geoelectric structure obtained in step S4, construct an initial resistivity model of the deep target layer and the underlying basement strata, and give the resistivity change distribution range of the upper Carboniferous (C 2 ), and control and fix the geoelectric structures of the middle and shallow N+E, T, J, and K cover layers; On the other hand, according to the top and bottom interface geological structure models of the upper Carboniferous (C 2 ) of the deep target layer obtained in step S5, give the burial depth data of the top and bottom interfaces of the upper Carboniferous (C 2 ) of the target layer; Combined with the given resistivity change distribution range of the deep target layer and the burial depth data of the top and bottom interfaces of the target layer, construct an initial geoelectric model of the deep target layer; S62. Use the time-frequency electromagnetic acquisition data obtained in step S1, refine and increase the number of inversion layers and the number of iterations of the deep target layer, and give the initial layer thickness and resistivity parameters for each layer. Use the simulated annealing constrained inversion method to perform focused fine inversion for the upper Carboniferous (C 2 ) of the deep target layer; During the inversion process, control and fix the geoelectric structures of the middle and shallow cover layers, forward calculate the amplitude and phase response data curves of the initial geoelectric model, compare with the measured data, calculate the fitting error, and through human-computer interaction, continuously modify the model parameters and the number of iterations of the target layer. When the fitting error reaches the set error standard, stop the calculation, complete the third resistivity inversion calculation of the upper Carboniferous (C 2 ) of the deep target layer, output the inversion result, and obtain a fine inversion high-resolution resistivity structure profile of the deep target layer, as Figure 7 shown. In this embodiment, when the fitting error is less than 1%, it is considered that the fitting error reaches the set error standard. The measured data refers to the amplitude and phase data curves of the field measured points.

[0033] During the inversion process, control and fix the geoelectric structures of the middle and shallow cover layers. For the deep target layer, refine and increase the number of layers of the initial model, as Figure 6As shown in a, in this embodiment, the number of initial model layers is increased from 12 to 24. At the same time, the number of inversion iterations is continuously increased, from 30 to 50 in this embodiment. The resistivity distribution ranges of the deep target layer and the underlying basement strata are determined based on the free inversion results. The fitting error is gradually reduced through multiple iterations, and the fitting error reaches the standard requirement of less than 1%, obtaining the inversion results as shown in Figure 6 b and Figure 7 . Comparing Figure 7 with Figure 3 , Figure 4 , it can be found that the longitudinal electrical resolution of the deep target layer has been significantly improved, and the internal structure of the upper Carboniferous (C 2 ) of the target layer is more clearly reflected.

[0034] The results obtained in step S6 will be used for the research on the geological structure and formation rock properties of the upper Carboniferous (C 2 ) of the deep target layer.

[0035] S7. Geologically interpret the high-resolution resistivity structure profile of the fine inversion of the upper Carboniferous (C 2 ) of the deep target layer, and study the geological structure and formation rock properties of the deep target layer. Specifically, in this step, on the fine inversion resistivity structure profile of the target layer obtained in step 6, combined with the formation rock physical property characteristics statistically analyzed in step 1, faults, electrical layers, and electrical anomaly bodies are interpreted to determine the geological structure and formation rock properties of the upper Carboniferous (C 2 ) of the deep target layer, and the obtained results are as shown in Figure 7 .

[0036] Embodiment 2 A deep target time-frequency electromagnetic constrained inversion interpretation device This embodiment is used to implement Embodiment 1, and it includes: a survey line, a collection module, a preprocessing module, a time-frequency electromagnetic conventional free inversion module, a time-frequency electromagnetic middle and 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 formation rock property determination module.

[0037] The survey line includes a time-frequency electromagnetic survey line for carrying out enhanced acquisition of the time-frequency electromagnetic target layer and a gravity acquisition survey line for carrying out gravity profile or area acquisition.

[0038] The collection module cooperates with the time-frequency electromagnetic survey line and the gravity acquisition survey line to carry out enhanced acquisition of the time-frequency electromagnetic target layer and gravity profile or area acquisition, and statistically analyzes the formation rock physical property data of the study area to obtain the time-frequency electromagnetic acquisition data, gravity acquisition data, and formation rock physical property characteristics of the measurement points.

[0039] A preprocessing module preprocesses the time-frequency electromagnetic acquisition data of the measuring points to obtain the amplitude and phase data of the measuring points, and preprocesses the gravity acquisition data to obtain the Bouguer gravity anomaly data.

[0040] A 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.

[0041] A time-frequency electromagnetic middle and shallow layer capping constraint inversion module is used to carry out the second resistivity inversion, obtain the fine geoelectric structure of the middle and shallow layer capping and the geoelectric structure of the deep free inversion.

[0042] A gravity-time-frequency electromagnetic-seismic profile joint inversion module is used to carry out the 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.

[0043] A 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.

[0044] A deep target layer geological structure and formation rock property determination module conducts geological interpretation on the fine inversion high-resolution resistivity structure profile of the deep target layer to study the geological structure and formation rock properties of the deep target layer.

[0045] Embodiment 3 A computer-readable storage medium In this embodiment, a computer program is stored in the computer-readable storage medium. When the computer program is executed by a processor, it is used to implement the deep target time-frequency electromagnetic constraint inversion and interpretation method in Embodiment 1.

[0046] Among them, 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-purpose 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 a component of the processor. The processor and the computer-readable storage medium can be located in an application specific integrated circuit (ASIC). Additionally, the ASIC can be located in the user equipment. Of course, the processor and the computer-readable storage medium can also exist as discrete components in the communication device. Specifically, the computer-readable storage medium can be implemented by any type of volatile or non-volatile storage device 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 memory, flash memory, a magnetic disk, or an optical disk. The storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer.

Claims

1. A deep target time-frequency electromagnetic constrained inversion interpretation method, comprising the following steps performed in sequence: S1. Carry out time-frequency electromagnetic acquisition and gravity acquisition work in the study area, statistically analyze the stratum rock property data in the study area, and obtain the time-frequency electromagnetic acquisition data, gravity acquisition data and stratum rock property characteristics of the measuring points; S2. Preprocessing the time-frequency electromagnetic data collected at the measuring point to obtain the amplitude and phase data of each measuring point, and preprocessing the gravity data collected at the measuring point to obtain the Bouguer gravity anomaly data of each measuring point; S3, using the amplitude and phase data of each measuring point, perform the first resistivity inversion to obtain the initial resistivity inversion profile in the depth domain, and further obtain the macro geoelectric model; It is characterized in that After completing step S3, perform the following steps in sequence: S4. Construct an initial resistivity model of the shallow to mid-layer cap layer based on the macroscopic geoelectric model, use seismic and drilling to control the position of the shallow to mid-layer strata, conduct a second resistivity inversion for the shallow to mid-layer cap layer, and obtain the fine geoelectric structure of the shallow to mid-layer cap layer and the free inversion geoelectric structure of the deep layer; S5. Based on the second resistivity inversion results and combined with the deep structure information reflected by the gravity anomaly, the initial geological-geophysical structure model of the profile is established through interpretation. Using the formation rock property characteristics and Bouguer gravity anomaly data, the gravity-time-frequency electromagnetic-seismic profile joint inversion is carried out to determine the geological structure model of the top and bottom interfaces of the deep target layer; S6. Construct an initial stratigraphic geological structure model of the deep target layer based on the top and bottom interface geological structure models of the deep target layer, construct an initial resistivity model of the deep target layer and underlying basement strata based on the deep free inversion geoelectric structure, perform a third resistivity inversion on the deep target layer, and obtain a high-resolution resistivity structural profile of the deep target layer by fine inversion; S7. Conduct geological interpretation of the deep target layer's fine inversion high-resolution resistivity structure profile to study the deep target layer's geological structure and formation rock properties.

2. The deep target time-frequency electromagnetic constrained inversion interpretation method according to claim 1 is characterized in that: The step S1 comprises the following steps which are performed in sequence: S11. Lay out time-frequency electromagnetic survey lines and gravity acquisition survey lines in the study area, overlapping with the seismic survey lines; S12. Conduct enhanced acquisition of time-frequency electromagnetic target layers and gravity profile or area acquisition; During the enhanced acquisition of the time-frequency electromagnetic target layer, the frequency response range of the deep target layer is first determined through well-seismic simulation, and a reasonable excitation cycle window is determined. Then, the acquisition frequency points are encrypted for the target layer to expand the data acquisition information. S13. According to the enhanced acquisition of the target layer in step S12, the time-frequency electromagnetic acquisition data of the measuring point is obtained.

3. The deep target time-frequency electromagnetic constrained inversion interpretation method according to claim 2 is characterized in that: Step S4 is performed in the following order: S41. Interpret the layers with clear reflection in the middle and shallow layers on the seismic profile and construct a geological layer model of the middle and shallow cover layer; S42, according to the petrophysical characteristics of the strata in the study area and the macro-geoelectric model obtained in step S3, the initial resistivity value is assigned to each layer of the middle and shallow cap geological strata, and a geological-geophysical structure model of the middle and shallow cap is established; at the same time, the 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 geoelectric structure of the middle and shallow layers is inverted according to the geological-geophysical structure model of the middle and shallow cap layers, and the deep geoelectric structure is freely inverted according to the initial geoelectric model of the deep layer. 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 cap layers and the freely inverted geoelectric structure of the deep layer.

4. The deep target time-frequency electromagnetic constrained inversion interpretation method according to claim 3 is characterized in that: Step S5 is performed in the following order: S51, conducting geological interpretation on the electrical layers and anomalies of the electrical structure of the second resistivity inversion profile and combining the deep structure information reflected by the gravity anomaly to establish an initial geological structure model of the profile for joint inversion of gravity-time-frequency electromagnetic-seismic profile; S52, on the one hand, according to the statistical analysis results of the formation rock physical property characteristics obtained in step S1, the electrical interpretation layers and abnormal bodies in the initial geological structure model of the profile are filled with corresponding density parameter values ​​to obtain the initial profile geological-geophysical model of the gravity-time-frequency electromagnetic-seismic profile joint inversion; 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. Use GeoGME processing and interpretation software platform to carry out gravity-time-frequency electromagnetic-seismic profile joint inversion; During inversion, the geological positions of each set of strata above the deep target layer with clear seismic reflection are fixed, and the top and bottom interface burial depths and fault positions of the deep target layer with unclear seismic reflection are adjusted and corrected. At the same time, the density parameter values ​​of each electrical interpretation layer and abnormal body filling are adjusted within the allowable range of the rock physical properties of the study area. The gravity anomaly curve is calculated according to the initial profile geological-geophysical model, and the calculated gravity anomaly curve is fitted with the measured residual gravity anomaly curve of the profile. According to the fitting situation, the initial profile geological-geophysical model is continuously adjusted and corrected through human-computer interaction. When the calculated gravity anomaly curve and the measured residual gravity anomaly curve of the profile reach the best fit and meet the preset fitting difference, the inversion calculation output result is stopped, that is, the geological-geophysical profile structural model of the deep target layer is obtained. Finally, the geological structural model of the top interface and the bottom interface of the deep target layer is determined through interpretation.

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

6. A deep target time-frequency electromagnetic constrained inversion interpretation device, used to implement the deep target time-frequency electromagnetic constrained inversion interpretation method according to any one of claims 1 to 5, characterized in that: include: Survey line, acquisition module, preprocessing module, time-frequency electromagnetic conventional free inversion module, time-frequency electromagnetic medium-shallow cap rock constraint inversion module, gravity-time-frequency electromagnetic-seismic profile joint inversion module, time-frequency electromagnetic deep target layer fine inversion module, deep target layer geological structure and formation rock attribute determination module; The survey lines include time-frequency electromagnetic survey lines for conducting enhanced acquisition of time-frequency electromagnetic target layers, and gravity acquisition survey lines for conducting gravity profile or area acquisition; The acquisition module cooperates with the time-frequency electromagnetic survey line and the gravity acquisition survey line to carry out the time-frequency electromagnetic target layer enhanced acquisition and gravity profile or area acquisition, and statistically analyzes the stratum rock physical property data of the study area to obtain the time-frequency electromagnetic acquisition data, gravity acquisition data and stratum rock physical property characteristics of the measuring point; The preprocessing module preprocesses the time-frequency electromagnetic data collected at the measuring point to obtain the amplitude and phase data of the measuring point, and preprocesses the gravity data collected 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 macro geoelectric model; The time-frequency electromagnetic medium-shallow cap layer constrained inversion module is used to carry out the second resistivity inversion to obtain the fine geoelectric structure of the medium-shallow cap layer and the deep free inversion geoelectric structure; Gravity-time-frequency electromagnetic-seismic profile joint inversion module, used to carry out gravity-time-frequency electromagnetic-seismic profile joint inversion and 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 and obtain the deep target layer fine inversion high-resolution resistivity structure profile; The deep target layer geological structure and formation rock property determination module performs geological interpretation on the deep target layer fine inversion high-resolution resistivity structure profile and studies the deep target layer geological structure and formation rock properties.

7. A computer-readable storage medium, characterized in that: A computer program is stored in a computer-readable storage medium, and when the computer program is executed by a processor, it is used to implement the deep target time-frequency electromagnetic constrained inversion interpretation method as described in any one of claims 1 to 5.

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