Electromagnetic temperature calculation method and device for simulating seismic inversion

Abstract

The invention relates to the technical field of electrical prospecting, and particularly discloses an electromagnetic temperature calculation method and device for simulating seismic inversion, and the method comprises the steps: obtaining a logging temperature curve based on logging information; the logging temperature curve is preprocessed; establishing a temperature initial model based on the preprocessed logging temperature curve; preprocessing the electromagnetic seismic data, and establishing electromagnetic simulated seismic data based on the preprocessed electromagnetic seismic data; carrying out seismic inversion based on the electromagnetic simulated seismic data and a temperature initial model; and displaying the heat storage body subjected to seismic inversion in a three-dimensional space. According to the invention, by means of the idea and steps of post-stack inversion in actual seismic exploration, seismic inversion is carried out based on electromagnetic simulated seismic data and a temperature initial model; and the heat storage body subjected to seismic inversion is displayed in a three-dimensional space, so that a new thought can be provided for magnetotelluric temperature inversion of a seismic exploration area, and the accuracy and credibility of electromagnetic temperature inversion are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of electrical exploration technology, specifically to a method and apparatus for electromagnetic temperature calculation using a pseudo-seismic inversion technique. Background Technology

[0002] Traditional methods for identifying underground temperatures in geothermal systems include well logging and geochemical thermography. While well logging is relatively accurate, it is limited to a single point within the exploration area and cannot meet the needs of comprehensive reservoir prediction and thermal reserve calculation. Geochemical thermography is simple to operate and inexpensive, but due to the complexity of groundwater channels, the depth at which the calculated temperature often lacks effective precision, and the results are easily affected by surface conditions. Therefore, its results are generally used for preliminary assessments in the early stages of exploration.

[0003] Existing electromagnetic temperature inversion techniques are mostly characterized by low inversion accuracy and small inversion range, and are rarely used for well logging data and structural interpretation data in actual seismic exploration.

[0004] Based on this technical background, the present invention studies a method and apparatus for electromagnetic temperature calculation using quasi-seismic inversion. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method and apparatus for electromagnetic temperature calculation based on pseudo-seismic inversion. This method utilizes the ideas and steps of post-stack inversion in actual seismic exploration to conduct seismic inversion based on electromagnetic pseudo-seismic data and an initial temperature model. It also displays the seismically inverted geothermal reservoir in three-dimensional space, providing a new approach for magnetotelluric temperature inversion in seismic exploration areas and significantly improving the accuracy and reliability of electromagnetic temperature inversion. This provides technical support for the next step of exploration and development of geothermal reservoirs.

[0006] To achieve the above objectives, a first aspect of the present invention provides a method for calculating electromagnetic temperature using a pseudo-seismic inversion method, comprising:

[0007] The logging temperature profile was obtained based on the logging data;

[0008] The well logging temperature curve is preprocessed;

[0009] Based on the preprocessed logging temperature curves, an initial temperature model is established.

[0010] Electromagnetic seismic data is preprocessed, and electromagnetic pseudo-seismic data is established based on the preprocessed electromagnetic seismic data.

[0011] Seismic inversion is carried out based on the electromagnetic pseudo-seismic data and the initial temperature model;

[0012] The seismically inverted thermal reservoir is displayed in three-dimensional space.

[0013] A second aspect of the present invention provides an electromagnetic temperature calculation device for quasi-seismic inversion, comprising:

[0014] The temperature profile acquisition module is used to obtain the logging temperature profile based on logging data.

[0015] A temperature curve preprocessing module is used to preprocess the well logging temperature curve;

[0016] The initial model building module is used to build an initial temperature model based on the preprocessed logging temperature curve;

[0017] The simulated seismic data establishment module is used to preprocess electromagnetic seismic data and establish electromagnetic simulated seismic data based on the preprocessed electromagnetic seismic data.

[0018] The earthquake inversion module is used to perform earthquake inversion based on the electromagnetic pseudo-seismic data and the initial temperature model.

[0019] The three-dimensional display module is used to display the seismically inverted thermal reservoir in three-dimensional space.

[0020] A third aspect of the present invention provides an electronic device, the electronic device comprising:

[0021] Memory, which stores executable instructions;

[0022] A processor that executes the executable instructions in the memory to implement the electromagnetic temperature calculation method for pseudo-seismic inversion as described in the first aspect.

[0023] A fourth aspect of the present invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the electromagnetic temperature calculation method for pseudo-seismic inversion described in the first aspect.

[0024] The beneficial effects of this invention include:

[0025] The electromagnetic temperature calculation method proposed in this invention, based on pseudo-seismic inversion, utilizes the ideas and steps of post-stack inversion in actual seismic exploration. It conducts seismic inversion based on electromagnetic pseudo-seismic data and an initial temperature model, and displays the seismically inverted geothermal reservoir in three-dimensional space. This method can provide a new approach for magnetotelluric temperature inversion in seismic exploration areas, and significantly improve the accuracy and reliability of electromagnetic temperature inversion, providing technical support for the next step of exploration and development of geothermal reservoirs.

[0026] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description

[0027] The above and other objects, features and advantages of the present invention will become more apparent from the more detailed description of exemplary embodiments of the invention in conjunction with the accompanying drawings.

[0028] Figure 1 This is a flowchart illustrating the electromagnetic temperature calculation method for pseudo-seismic inversion proposed in this invention.

[0029] Figure 2 This is a schematic diagram of a temperature curve obtained based on well logging data in a specific implementation of the electromagnetic temperature calculation method for pseudo-seismic inversion proposed in this invention.

[0030] Figure 3 This is a schematic diagram of the preprocessing results of temperature curves from four different wells in a specific embodiment of the electromagnetic temperature calculation method for pseudo-seismic inversion proposed in this invention.

[0031] Figure 4 This is a schematic diagram illustrating the results of seismic tectonic interpretation in a specific implementation of the electromagnetic temperature calculation method for pseudo-seismic inversion proposed in this invention.

[0032] Figure 5 This is a schematic diagram illustrating the establishment of the initial temperature model in a specific implementation of the electromagnetic temperature calculation method for pseudo-seismic inversion proposed in this invention.

[0033] Figure 6 This is a schematic diagram of temperature inversion results in a specific embodiment of the electromagnetic temperature calculation method for pseudo-seismic inversion proposed in this invention.

[0034] Figure 7 This is a schematic diagram of a three-dimensional temperature volume in a specific embodiment of the electromagnetic temperature calculation method for pseudo-seismic inversion proposed in this invention.

[0035] Figure 8 This is a schematic diagram of a three-dimensional temperature volume engraving display in a specific embodiment of the electromagnetic temperature calculation method for pseudo-seismic inversion proposed in this invention. Detailed Implementation

[0036] Preferred embodiments of the invention will now be described in more detail. While preferred embodiments of the invention are described below, it should be understood that the invention can be implemented in various forms and should not be limited to the embodiments set forth herein.

[0037] This invention provides a method for calculating electromagnetic temperature using quasi-seismic inversion, such as... Figure 1 As shown, it includes:

[0038] The logging temperature profile was obtained based on the logging data;

[0039] Preprocess the logging temperature curves;

[0040] An initial temperature model is established based on the preprocessed logging temperature curves.

[0041] Electromagnetic seismic data is preprocessed, and electromagnetic pseudo-seismic data is established based on the preprocessed electromagnetic seismic data.

[0042] Seismic inversion was carried out based on electromagnetic pseudo-seismic data and an initial temperature model.

[0043] The seismically inverted thermal reservoir is displayed in three-dimensional space.

[0044] In this invention, by adopting the ideas and steps of post-stack inversion in actual seismic exploration, seismic inversion is carried out based on electromagnetic pseudo-seismic data and initial temperature models; and the geothermal reservoirs obtained from the seismic inversion are displayed in three-dimensional space. This can provide a new approach for magnetotelluric temperature inversion in seismic exploration areas, and significantly improve the accuracy and reliability of electromagnetic temperature inversion, providing technical support for the next step of exploration and development of geothermal reservoirs, etc.

[0045] According to the present invention, the preprocessing methods for well logging temperature curves include normalization, noise reduction, smoothing, and stratified correction.

[0046] According to the present invention, the initial temperature model is established based on the preprocessed logging temperature curve, including:

[0047] Based on the preprocessed well logging temperature curves, and with the help of the stratigraphic results interpreted from seismic tectonics, an initial inversion model is established using interpolation and extrapolation.

[0048] According to the present invention, the preprocessing methods for electromagnetic seismic data include data quality assessment, data cleaning, data conversion, data normalization, data interpolation, data noise reduction, data filtering, data standardization, data integration, and data pruning.

[0049] According to the present invention, the establishment of electromagnetic pseudo-seismic data based on preprocessed electromagnetic seismic data includes:

[0050] The resistivity in the preprocessed electromagnetic seismic data is equivalent to the magnitude of the seismic reflection coefficient.

[0051] Using the standard Ricker wavelet as the initial seismic wavelet for calculation, convolution model calculations of reflection earthquakes were carried out to obtain electromagnetic pseudo-seismic data.

[0052] Preferably, the dominant frequency range of the standard Ricker wavelet is 30-40Hz;

[0053] Electromagnetic pseudoseismic data must satisfy the spatial sampling theorem on seismic data.

[0054] According to the present invention, the pseudo-seismic wavelet of seismic inversion is extracted from electromagnetic pseudo-seismic data;

[0055] Earthquake inversion methods include direct inversion, iterative inversion, regularized inversion, constrained inversion, and statistical inversion.

[0056] Example 1:

[0057] like Figure 1 As shown in the figure, this embodiment proposes a method for calculating electromagnetic temperature using quasi-seismic inversion, and the specific steps are as follows:

[0058] ① Interpretation of temperature data from well logging data;

[0059] The qualitative relationship between formation temperature and key parameters was established through cross-analysis of well logging temperature and geophysical parameters such as acoustic velocity and resistivity. During the analysis, the influence of formation, lithology and water-bearing properties were fully considered. The analysis was conducted by segmenting the formation, classifying the lithology, and conducting independent cross-analysis of dry rock and water-bearing layers. Finally, the cross-relationship between well logging geophysical parameters and temperature was established, and the temperature data of each seismic well was obtained.

[0060] This technology is the property of the patent holder. For specific steps and details, please refer to (Patent No. ZL201710884479.3).

[0061] In this embodiment, the temperature curve obtained based on well logging data is as follows: Figure 2 As shown;

[0062] ② Preprocessing of well logging temperature profiles;

[0063] To meet the needs of inverted logging data, the temperature curves obtained in step 1 are preprocessed. Combining the geological stratification and geodetic temperature trend information of the logging data, the preprocessing work of the logging temperature curves is carried out, which mainly includes the following steps: normalization, noise reduction, smoothing, and stratification correction of the temperature curves. Through a series of preprocessing steps, the logging temperature curves are made more consistent with geological laws, which also lays the foundation for the subsequent establishment of the initial model using the results of structural interpretation.

[0064] In this embodiment, the preprocessing results of the temperature curves from four different well logging sites are as follows: Figure 3 As shown;

[0065] ③ Establishment of the initial temperature model;

[0066] With the temperature curves and the stratigraphic results interpreted from the seismic tectonics, an initial inversion model can be established using methods such as interpolation and extrapolation.

[0067] There are many algorithms for establishing the initial model in earthquake inversion, which will not be elaborated here. The innovation of the temperature curve in this patent is twofold: first, it replaces the traditional elastic parameter curve or physical property parameter curve with a temperature curve; second, it combines the previous geological understanding, especially the results of geological stratification, in the inversion process to establish an initial model for the overall temperature inversion of different types of strata.

[0068] In this embodiment, the results of seismic tectonic interpretation and the establishment of the initial temperature model are as follows: Figure 4 and Figure 5 As shown;

[0069] ④ Preprocessing of electromagnetic data;

[0070] Electromagnetic data preprocessing typically includes the following steps: data quality assessment, data cleaning, data transformation, data normalization, data interpolation, data noise reduction, data filtering, data standardization, data integration, and data pruning. These preprocessing steps can better prepare and process data from wide-area electromagnetic methods, laying the foundation for subsequent data analysis and interpretation.

[0071] ⑤ Establish simulated earthquake data:

[0072] Electromagnetic data mainly reflects the longitudinal variation of apparent resistivity with frequency at the measuring point, while conventional seismic exploration data mainly reflects the longitudinal variations of seismic wave amplitude and phase. Therefore, data from the wide-area electromagnetic method can be converted into data from pseudo-seismic curves.

[0073] The specific method is as follows: the magnitude of resistivity is equivalent to the magnitude of seismic reflection coefficient. The standard Ricker wavelet is used as the initial seismic wavelet for calculation. The convolution model of the reflected seismic data is then used to calculate the pseudo-seismic curvature data of the electromagnetic data. Considering the dominant frequency range of the seismic data, the dominant frequency range of the Ricker wavelet is generally around 35Hz. At the same time, it is necessary to consider that the converted data must satisfy the spatial sampling theorem on the seismic data to avoid spatial aliasing and insufficient sampling.

[0074] ⑥ Temperature inversion based on electrical data;

[0075] With electromagnetic pseudo-seismic data and an initial temperature model, the pseudo-seismic wavelet can be directly extracted from the electromagnetic pseudo-seismic data, thus enabling seismic inversion.

[0076] Earthquake inversion methods include direct inversion, iterative inversion, regularized inversion, constrained inversion, statistical inversion, etc., all of which can obtain the desired temperature volume.

[0077] In this embodiment, the temperature inversion result is as follows: Figure 6 As shown;

[0078] ⑦ Three-dimensional visualization of the temperature of the thermal reservoir;

[0079] For efficient utilization in actual geothermal exploration and development, the inverted geothermal reservoir needs to be displayed in three-dimensional space to facilitate subsequent efficient development. Therefore, three-dimensional visualization tools are used to display and sculpt the three-dimensional temperature volume in a stereoscopic manner, such as... Figure 7 and Figure 8 As shown, the engraving can further clarify information about exploitable geothermal resources, such as the shape and boundaries of geothermal reservoirs.

[0080] Example 2:

[0081] This embodiment provides a method for calculating electromagnetic temperature using quasi-seismic inversion, such as... Figure 1 As shown, it includes:

[0082] The logging temperature profile was obtained based on the logging data;

[0083] Preprocess the logging temperature curves;

[0084] An initial temperature model is established based on the preprocessed logging temperature curves.

[0085] Electromagnetic seismic data is preprocessed, and electromagnetic pseudo-seismic data is established based on the preprocessed electromagnetic seismic data.

[0086] Seismic inversion was carried out based on electromagnetic pseudo-seismic data and an initial temperature model.

[0087] Displaying seismically inverted thermal reservoirs in three-dimensional space;

[0088] In this embodiment, the preprocessing methods for the logging temperature curve include normalization, noise reduction, smoothing, and stratified correction.

[0089] In this embodiment, the initial temperature model is established based on the preprocessed logging temperature curve, including:

[0090] Based on the preprocessed well logging temperature curves, and with the help of the stratigraphic results interpreted by seismic tectonics, an initial inversion model is established using interpolation and extrapolation.

[0091] In this embodiment, the preprocessing methods for electromagnetic seismic data include data quality assessment, data cleaning, data conversion, data normalization, data interpolation, data noise reduction, data filtering, data standardization, data integration, and data pruning.

[0092] In this embodiment, establishing electromagnetic pseudo-seismic data based on preprocessed electromagnetic seismic data includes:

[0093] The resistivity in the preprocessed electromagnetic seismic data is equivalent to the magnitude of the seismic reflection coefficient.

[0094] Using the standard Ricker wavelet as the initial seismic wavelet, we performed convolutional model calculations for reflection earthquakes to obtain electromagnetic pseudo-seismic data.

[0095] In this embodiment, the dominant frequency range of the standard Lake wavelet is 30-40Hz;

[0096] Electromagnetic pseudoseismic data must satisfy the spatial sampling theorem on seismic data;

[0097] In this embodiment, the pseudo-seismic wavelet of the seismic inversion is extracted from electromagnetic pseudo-seismic data;

[0098] Earthquake inversion methods include direct inversion, iterative inversion, regularized inversion, constrained inversion, and statistical inversion.

[0099] Example 3:

[0100] This embodiment provides an electromagnetic temperature calculation device for pseudo-seismic inversion, comprising:

[0101] The temperature profile acquisition module is used to obtain the logging temperature profile based on logging data.

[0102] The temperature profile preprocessing module is used to preprocess the logging temperature profiles.

[0103] The initial model building module is used to build an initial temperature model based on the preprocessed well logging temperature curves.

[0104] The simulated seismic data creation module is used to preprocess electromagnetic seismic data and create electromagnetic simulated seismic data based on the preprocessed electromagnetic seismic data.

[0105] The earthquake inversion module is used to perform earthquake inversion based on electromagnetic pseudo-seismic data and an initial temperature model.

[0106] The 3D display module is used to display the seismically inverted thermal reservoir in three-dimensional space;

[0107] In this embodiment, the preprocessing methods for the logging temperature curve include normalization, noise reduction, smoothing, and stratified correction.

[0108] In this embodiment, the initial temperature model is established based on the preprocessed logging temperature curve, including:

[0109] Based on the preprocessed well logging temperature curves, and with the help of the stratigraphic results interpreted by seismic tectonics, an initial inversion model is established using interpolation and extrapolation.

[0110] In this embodiment, the preprocessing methods for electromagnetic seismic data include data quality assessment, data cleaning, data conversion, data normalization, data interpolation, data noise reduction, data filtering, data standardization, data integration, and data pruning.

[0111] In this embodiment, establishing electromagnetic pseudo-seismic data based on preprocessed electromagnetic seismic data includes:

[0112] The resistivity in the preprocessed electromagnetic seismic data is equivalent to the magnitude of the seismic reflection coefficient.

[0113] Using the standard Ricker wavelet as the initial seismic wavelet, we performed convolutional model calculations for reflection earthquakes to obtain electromagnetic pseudo-seismic data.

[0114] In this embodiment, the dominant frequency range of the standard Lake wavelet is 30-40Hz;

[0115] Electromagnetic pseudoseismic data must satisfy the spatial sampling theorem on seismic data;

[0116] In this embodiment, the pseudo-seismic wavelet of the seismic inversion is extracted from electromagnetic pseudo-seismic data;

[0117] Earthquake inversion methods include direct inversion, iterative inversion, regularized inversion, constrained inversion, and statistical inversion.

[0118] Example 4:

[0119] This invention provides an electronic device including a memory and a processor.

[0120] Memory, which stores executable instructions;

[0121] The processor executes executable instructions in memory to implement the electromagnetic temperature calculation method for pseudo-seismic inversion.

[0122] This memory is used to store non-transitory computer-readable instructions. Specifically, the memory may include one or more computer program products, which may include various forms of computer-readable storage media, such as volatile memory and / or non-volatile memory. The volatile memory may, for example, include random access memory (RAM) and / or cache memory. The non-volatile memory may, for example, include read-only memory (ROM), hard disk, flash memory, etc.

[0123] The processor may be a central processing unit (CPU) or other form of processing unit with data processing capabilities and / or instruction execution capabilities, and may control other components in the electronic device to perform desired functions. In one embodiment of the invention, the processor is used to execute computer-readable instructions stored in the memory.

[0124] Those skilled in the art should understand that, in order to solve the technical problem of how to achieve a good user experience, this embodiment may also include well-known structures such as communication buses and interfaces, and these well-known structures should also be included within the protection scope of this invention.

[0125] For a detailed description of this embodiment, please refer to the corresponding descriptions in the foregoing embodiments, which will not be repeated here.

[0126] Example 5:

[0127] This invention provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements an electromagnetic temperature calculation method for pseudo-seismic inversion.

[0128] A computer-readable storage medium according to embodiments of the present invention stores non-transitory computer-readable instructions. When these non-transitory computer-readable instructions are executed by a processor, all or part of the steps of the methods described in the foregoing embodiments of the present invention are performed.

[0129] The aforementioned computer-readable storage media include, but are not limited to: optical storage media (e.g., CD-ROM and DVD), magneto-optical storage media (e.g., MO), magnetic storage media (e.g., magnetic tape or portable hard drive), media with built-in rewritable non-volatile memory (e.g., memory card), and media with built-in ROM (e.g., ROM cartridge).

[0130] The electromagnetic temperature calculation method based on pseudo-seismic inversion proposed in the embodiments of the present invention, by adopting the ideas and steps of post-stack inversion in actual seismic exploration, conducts seismic inversion based on electromagnetic pseudo-seismic data and initial temperature model; and displays the seismically inverted geothermal reservoir in three-dimensional space, which can provide a new approach for magnetotelluric temperature inversion in seismic exploration areas, and significantly improve the accuracy and reliability of electromagnetic temperature inversion, providing technical support for the next step of exploration and development of geothermal reservoirs, etc.

[0131] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for calculating electromagnetic temperature using quasi-seismic inversion, characterized in that, include: The logging temperature profile was obtained based on the logging data; The well logging temperature curve is preprocessed; Based on the preprocessed logging temperature curves, an initial temperature model is established. Electromagnetic seismic data is preprocessed, and electromagnetic pseudo-seismic data is established based on the preprocessed electromagnetic seismic data. Seismic inversion is carried out based on the electromagnetic pseudo-seismic data and the initial temperature model; The seismically inverted thermal reservoir is displayed in three-dimensional space.

2. The method according to claim 1, characterized in that, The preprocessing methods for the well logging temperature curves include normalization, noise reduction, smoothing, and stratified correction.

3. The method according to claim 1, characterized in that, Based on the preprocessed logging temperature curves, an initial temperature model is established, including: Based on the preprocessed well logging temperature curves, and with the help of the stratigraphic results interpreted from seismic tectonics, an initial inversion model is established using interpolation and extrapolation.

4. The method according to claim 1, characterized in that, Methods for preprocessing electromagnetic seismic data include data quality assessment, data cleaning, data transformation, data normalization, data interpolation, data noise reduction, data filtering, data standardization, data integration, and data trimming.

5. The method according to claim 1, characterized in that, The creation of electromagnetic pseudo-seismic data based on the preprocessed electromagnetic seismic data includes: The resistivity in the preprocessed electromagnetic seismic data is equivalent to the magnitude of the seismic reflection coefficient. Using the standard Ricker wavelet as the initial seismic wavelet for calculation, convolution model calculations of reflection earthquakes were carried out to obtain electromagnetic pseudo-seismic data.

6. The method according to claim 5, characterized in that, The dominant frequency range of the standard Lake wavelet is 30-40Hz; The electromagnetic pseudo-seismic data must satisfy the spatial sampling theorem on the seismic data.

7. The method according to claim 1, characterized in that, The pseudo-seismic wavelet of the earthquake inversion is extracted from the electromagnetic pseudo-seismic data; The earthquake inversion methods include direct inversion, iterative inversion, regularized inversion, constrained inversion, and statistical inversion.

8. An electromagnetic temperature calculation device for quasi-seismic inversion, characterized in that, include: The temperature profile acquisition module is used to obtain the logging temperature profile based on logging data. A temperature curve preprocessing module is used to preprocess the well logging temperature curve; The initial model building module is used to build an initial temperature model based on the preprocessed logging temperature curve; The simulated seismic data establishment module is used to preprocess electromagnetic seismic data and establish electromagnetic simulated seismic data based on the preprocessed electromagnetic seismic data. The earthquake inversion module is used to perform earthquake inversion based on the electromagnetic pseudo-seismic data and the initial temperature model. The three-dimensional display module is used to display the seismically inverted thermal reservoir in three-dimensional space.

9. An electronic device, characterized in that, The electronic device includes: Memory, which stores executable instructions; A processor that executes the executable instructions in the memory to implement the electromagnetic temperature calculation method for pseudo-seismic inversion according to any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the electromagnetic temperature calculation method for pseudo-seismic inversion as described in any one of claims 1-7.

Images