Method and device for predicting total organic carbon content of shale

Abstract

The invention provides a method and device for predicting the total organic carbon content of shale, and the method comprises the steps: selecting shale samples from a plurality of wells for testing, obtaining the total organic carbon content and the wave impedance value of the shale, carrying out the correlation analysis of the total organic carbon content and the wave impedance value, and selecting a target well with the correlation greater than a preset threshold value; in the target well, shale total organic carbon content and wave impedance data from wells in different layers in different blocks are obtained; drawing a cross plot of the total organic carbon content and the wave impedance of different layers of different blocks; constructing a quantitative relational expression between the total organic carbon content and the wave impedance of different blocks and different layers on the basis of the cross plot; acquiring wave impedance data of a to-be-predicted well, and predicting shale distribution according to the wave impedance data; and substituting the wave impedance data of the shale distribution area into a quantitative relational expression corresponding to the block and the horizon of the shale distribution area, and predicting the total organic carbon content of the shale. According to the method, the total organic carbon content of the shale can be predicted more accurately.

Description

Technical Field

[0001] The invention belongs to the technical field of petroleum exploration, and in particular relates to a method and a device for predicting the total organic carbon content of shale. Background Art

[0002] Quantitative characterization of shale and prediction of the distribution of total organic carbon (TOC) in shale are of great significance for shale oil and gas exploration and development, and oil and gas resource evaluation.

[0003] At present, seismic inversion is a very important method for predicting TOC content in shale. The relationship between acoustic impedance and TOC is established through seismic inversion, and then the wave impedance data is converted into TOC content. Since wave impedance is affected by many factors such as sedimentary phase and diagenesis in the inversion area, it leads to complex changes in wave impedance value, thereby reducing the correlation between wave impedance and TOC. Further, the prediction accuracy of TOC content is poor. Summary of the invention

[0004] In order to solve the problem of poor TOC prediction accuracy in shale in the prior art, the present invention provides a method and device for predicting the total organic carbon content of shale.

[0005] In order to achieve the above object, the present invention provides the following technical solutions: A method for predicting total organic carbon content of shale, characterized by comprising: Select shale samples from multiple wells for testing, obtain the total organic carbon content and wave impedance value of the shale, perform correlation analysis on the total organic carbon content and wave impedance value, and select target wells where the correlation is greater than a preset threshold; In the target well, the total organic carbon content and wave impedance data of shale from wells in different layers of different blocks are obtained; the intersection diagram of total organic carbon content and wave impedance in different layers of different blocks is drawn; based on the intersection diagram, the quantitative relationship between total organic carbon content and wave impedance in different layers of different blocks is constructed; Obtain the wave impedance data of the well to be predicted, and predict the shale distribution based on the wave impedance data; substitute the wave impedance data of the shale distribution area into the quantitative relationship corresponding to the block and layer where the shale distribution area is located to predict the total organic carbon content of the shale.

[0006] Optionally, the shale distribution is predicted based on the wave impedance data, including: Obtain logging data of typical wells in different layers of different blocks, and draw wave impedance frequency distribution diagrams corresponding to shales with different total organic carbon contents and wave impedance frequency distribution diagrams corresponding to sandstones based on the logging data; According to the wave impedance frequency distribution diagram, the threshold values ​​for distinguishing shale and sandstone in different layers in different blocks are determined; The wave impedance data is compared with the threshold value of the corresponding block and layer. If it is less than or equal to the threshold value, it is mud shale.

[0007] Optionally, obtaining the wave impedance data of the well to be predicted includes: Obtaining density logging curves and acoustic logging curves of the well to be predicted; calculating wave impedance data according to the density logging curves and acoustic logging curves; or, The seismic data of the well to be predicted is obtained, and the wave impedance data is obtained through an inversion algorithm based on the seismic data and the wave impedance model.

[0008] Optionally, after predicting the shale distribution and the total organic carbon content of the shale, the method further includes: Based on the predicted shale distribution and predicted total organic carbon content, a high-quality source rock thickness map and a planar distribution map of total organic carbon content were drawn.

[0009] Optionally, the plurality of wells are typical wells reflecting characteristics of source rocks.

[0010] The present invention also provides a device for predicting the total organic carbon content of shale, comprising: An analysis module is used to select shale samples from multiple wells for testing, obtain the total organic carbon content and wave impedance value of the shale, perform correlation analysis on the total organic carbon content and the wave impedance value, and select target wells where the correlation is greater than a preset threshold; A construction module is used to obtain the total organic carbon content and wave impedance data of shale from wells at different layers in different blocks in the target well; draw the intersection diagram of the total organic carbon content and wave impedance at different layers in different blocks; and construct the quantitative relationship between the total organic carbon content and wave impedance at different layers in different blocks based on the intersection diagram; The prediction module is used to obtain the wave impedance data of the well to be predicted, and predict the shale distribution based on the wave impedance data; substitute the wave impedance data of the shale distribution area into the quantitative relationship corresponding to the block and layer where the shale distribution area is located, and predict the total organic carbon content of the shale.

[0011] The present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor implements the above-mentioned method for predicting the total organic carbon content of shale when executing the program.

[0012] The present invention also provides a computer-readable storage medium, wherein the storage medium stores a computer program, and when the computer program is executed by a processor, the above-mentioned method for predicting the total organic carbon content of shale is implemented.

[0013] The method for predicting the total organic carbon content of shale provided by the present invention has the following beneficial effects: The present invention performs correlation analysis on the total organic carbon content and wave impedance value of mud shale in multiple wells, selects target wells with correlation greater than a preset threshold for analysis, and constructs quantitative relationship formulas between the total organic carbon content and wave impedance in different blocks and different layers to predict the total organic carbon content of mud shale; firstly, target wells with correlation greater than a preset threshold are selected for analysis, and the data of these wells can better reflect the true relationship between TOC and wave impedance; secondly, since different layers represent strata with different lithological characteristics and sedimentary environments, different blocks will also have different sedimentary environments, which will have different effects on wave impedance, therefore, the quantitative relationship formula between the total organic carbon content and the wave impedance is constructed by classification according to the blocks and layers, so that the correlation between the wave impedance and the total organic carbon content in the quantitative relationship is stronger, and a more accurate prediction of the total organic carbon content can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiment of the present invention and its design scheme, the following briefly introduces the drawings required for this embodiment. The drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 A schematic flow chart of a method for predicting the total organic carbon content of shale provided in an embodiment of the present invention; Figure 2 A relationship diagram between TOC content and wave impedance of wells in different blocks provided by an embodiment of the present invention; Figure 2 Figure (a) shows the relationship between TOC content and wave impedance corresponding to the W1 block; Figure 2 Figure (b) shows the relationship between TOC content and wave impedance corresponding to block W2; Figure 2 Figure (c) shows the relationship between TOC content and wave impedance corresponding to block W3; Figure 2 Figure (d) shows the relationship between TOC content and wave impedance corresponding to block W4; Figure 3 A wave impedance frequency distribution diagram corresponding to different blocks in different layers provided by an embodiment of the present invention; Figure 3 Figure (a) is the wave impedance frequency distribution diagram corresponding to the W9 block in the E1 layer; Figure 3 Figure (b) is the wave impedance frequency distribution diagram corresponding to the W10 block in the E1 layer; Figure 3 Figure (c) is the wave impedance frequency distribution diagram corresponding to the W19 block in the E1 layer; Figure 3 Figure (d) is the wave impedance frequency distribution diagram corresponding to the W5 block in the E1 layer. DETAILED DESCRIPTION

[0016] In order to enable those skilled in the art to better understand the technical solution of the present invention and implement it, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the scope of protection of the present invention.

[0017] In the description of the present invention, it is to be understood that the terms “center”, “longitudinal”, “lateral”, “length”, “width”, “thickness”, “up”, “down”, “front”, “back”, “left”, “right”, “vertical”, “horizontal”, “top”, “bottom”, “inside”, “outside”, “axial”, “radial”, “circumferential”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the technical solutions of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0018] In addition, the terms "first", "second", etc. are used for descriptive purposes only and are not to be understood as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless otherwise clearly specified or limited, the terms "connected" and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances. In the description of the present invention, unless otherwise specified, "plurality" means two or more, which will not be described in detail here.

[0019] Before introducing the present invention, some terms related to the present invention are introduced.

[0020] Sedimentary facies refers to the formation environment and characteristics of sediments. Different sedimentary facies have different rock compositions, structures and sedimentary environments, which directly affect the physical properties of rocks, including wave impedance. For example, some reservoir sandstones in the Ordos Basin show strong variability, complexity and heterogeneity in their petrological characteristics, pore structures and physical properties due to different sedimentary environments. These characteristics affect the correlation between wave impedance and TOC.

[0021] Diagenesis refers to the various geological processes in the process of sediments turning into rocks. These processes, such as compaction, cementation, and dissolution, will change the pore structure and physical properties of the rock, thereby affecting the wave impedance. For example, compaction and cementation are the main reasons for the deterioration of reservoir physical properties. These processes change the wave impedance value of the rock and affect its correlation with TOC.

[0022] In summary, the combined influence of sedimentary facies, diagenesis and other factors leads to complex changes in wave impedance values, which reduces its correlation with TOC and affects the accuracy of TOC prediction.

[0023] Based on the problem of poor TOC prediction accuracy in shale in the prior art, an embodiment of the present invention provides a method for predicting the total organic carbon content of shale, such as Figure 1 As shown, the method comprises the following steps: S1, select shale samples from multiple wells for testing, obtain the total organic carbon content and wave impedance value of the shale, perform correlation analysis on the total organic carbon content and wave impedance value, and select target wells whose correlation is greater than a preset threshold.

[0024] Among them, a plurality of wells are typical wells with high quality and strong representativeness of logging data. Optionally, wells reflecting source rock characteristics among a plurality of candidate wells can be used as typical wells, and the selection of these wells is based on a plurality of key characteristics of source rocks, so as to more accurately evaluate the potential of source rocks and the oil and gas resources formed by them.

[0025] For example, shale core samples are collected from typical wells, and the depth, lithology, and geological background information of the samples are recorded. The samples are tested in the laboratory to obtain the TOC content and wave impedance values. Statistical software, such as Excel or Python, is used to draw an intersection diagram of the TOC content and wave impedance of a single well sample point, and a correlation coefficient, such as the Pearson correlation coefficient, is calculated to evaluate the correlation between the two, and finally a target well with a correlation greater than a preset threshold (e.g., 70%) is selected.

[0026] Optionally, the total organic carbon (TOC) content may be measured by a thermal oxidation method, a wet oxidation method, or the like. The embodiment of the present invention does not specifically limit the method for measuring the total organic carbon content.

[0027] S2, in the target well, obtain the total organic carbon content and wave impedance data of shale from wells in different layers of different blocks; draw the intersection diagram of total organic carbon content and wave impedance in different layers of different blocks; and construct the quantitative relationship between total organic carbon content and wave impedance in different layers of different blocks based on the intersection diagram.

[0028] In the embodiment of the present invention, the strata in the study area are divided into the E horizon (Enping Formation) and the W horizon (Wenchang Formation). The E horizon can be further divided into two secondary stratigraphic units, E1 and E2, according to lithology changes, fossil assemblages, sedimentary environment changes, etc. The block division divides the area into Block A (depression) and Block B (depression). Block A represents the northern half of the basin, and Block B represents the southern half of the basin. Blocks A and B have different sedimentary phases and diagenesis.

[0029] The following is an introduction to the Enping Formation and the Wenchang Formation: Enping Formation: It is mainly formed in lake and delta environments, mainly fine-grained sediments. Its rock characteristics are usually dominated by mudstone and shale, and it is an important source rock.

[0030] Wenchang Formation: Mainly a lake environment, the sediment grain size is coarser than that of the Wenchang Formation. In addition to mudstone, it also contains sandstone and coal seams, showing a more complex sedimentary sequence.

[0031] It can be seen that the Enping Formation and the Wenchang Formation have different lithological characteristics and sedimentary environments, and there are also significant differences in diagenesis and sedimentary facies.

[0032] Furthermore, the total organic carbon content and wave impedance data of shale in different strata and wells in different blocks were obtained, and the intersection diagrams of total organic carbon content and wave impedance in different layers of different blocks were drawn, such as Figure 2 As shown, Figure 2 A schematic diagram of an intersection diagram of total organic carbon content and wave impedance in different blocks provided in an embodiment of the present invention.

[0033] For example, Figure 2 As shown, W1-W4 are sub-blocks formed by dividing block A and block B according to a preset rule. Figure 2 In the above figure, the horizontal axis of each histogram is wave impedance, and the vertical axis is TOC content. The quantitative relationship between the total organic carbon content and wave impedance of the wells in the sub-block can be constructed by the change of TOC content with wave impedance. In the quantitative relationship, x represents wave impedance and y represents TOC content. Furthermore, the correlation coefficient R between wave impedance and TOC content can be obtained by analyzing the histogram. 2 For example, in the W1 well, the correlation coefficient between wave impedance and TOC content is 0.9187, that is, the correlation is greater than 90%. By observing that the correlation coefficients between wave impedance and TOC content in each sub-block well are all above 70%, it can be seen that dividing the study area into blocks can improve the correlation between wave impedance and TOC content.

[0034] Similarly, for different strata, a quantitative relationship between the total organic carbon content and wave impedance can also be established.

[0035] In the present invention, the horizon and the block can be studied separately, or the horizon and the block can be studied together. Specifically, the total organic carbon content and wave impedance data of different blocks in each horizon are obtained, and the intersection diagram of the total organic carbon content and wave impedance of different blocks in each horizon is drawn, and then the quantitative relationship corresponding to the different blocks in each horizon is established, for example, the quantitative relationship corresponding to the A block of the E horizon, the quantitative relationship corresponding to the B block of the E horizon, the quantitative relationship corresponding to the A block of the W horizon, the quantitative relationship corresponding to the B block of the W horizon, etc.

[0036] S3, obtaining the wave impedance data of the well to be predicted, and predicting the shale distribution according to the wave impedance data; substituting the wave impedance data of the shale distribution area into the quantitative relationship corresponding to the block and layer where the shale distribution area is located, and predicting the total organic carbon content of the shale.

[0037] In the present invention, the wave impedance data of the well to be predicted can be obtained in the following two ways.

[0038] Method 1: Obtain the density logging curve and the acoustic logging curve of the well to be predicted; calculate the wave impedance data according to the density logging curve and the acoustic logging curve.

[0039] Specifically, the acoustic time difference value of each depth point is obtained from the acoustic logging data ( ), and then use the following formula to calculate the P-wave velocity at each depth point ( ): .

[0040] Then, the density value of each depth point is obtained from the density logging data, and the P-wave velocity at each depth point is multiplied by the density value to obtain the wave impedance (AI) of the point.

[0041] Method 2: Obtain seismic data of the well to be predicted, and obtain wave impedance data through an inversion algorithm based on the seismic data.

[0042] Specifically, the seismic data of the well to be predicted are obtained, and the seismic data are preprocessed, including denoising, filtering, improving the signal-to-noise ratio, etc., to obtain high-quality seismic records; seismic wavelets are extracted according to the seismic records, and the convolution relationship between the seismic records and the seismic wavelets is used to extract the reflection coefficient sequence through the deconvolution method; the inversion algorithm is determined, such as generalized linear inversion, iterative inversion, trace integral inversion, etc.; the extracted reflection coefficient sequence and the given initial value of the wave impedance are input into the inversion algorithm, and the corresponding wave impedance sequence is obtained through the calculation of the inversion algorithm.

[0043] Furthermore, the shale distribution is predicted based on the wave impedance data.

[0044] The present invention analyzes wave impedance histograms of different lithologies and sets lithology discrimination thresholds of different blocks and different layers to distinguish sandstone and shale.

[0045] Specifically, the process is as follows: Step 1: Obtain logging data from wells in different layers in different blocks, and draw wave impedance frequency distribution diagrams corresponding to shales with different total organic carbon contents and wave impedance frequency distribution diagrams corresponding to sandstones based on the logging data.

[0046] Among them, logging data include sonic logging data, density logging data, resistivity logging data and natural gamma ray spectrum logging (NGS) data.

[0047] For example, acoustic logging data and density logging data are used to calculate wave impedance; natural gamma ray spectrum, acoustic wave, density and resistivity logging data are used to evaluate TOC content; for shale, wave impedance data are classified according to different TOC contents; statistical methods (such as histograms) are used to display the frequency distribution of wave impedance of different classifications. Figure 3 As shown, Figure 3 The wave impedance frequency distribution diagram corresponding to different blocks in different layers is shown.

[0048] Step 2: Determine the threshold value for distinguishing shale and sandstone in different layers and blocks based on the wave impedance frequency distribution diagram.

[0049] For example, Figure 3 As shown in the figure, according to the changing trend of the wave impedance frequency of shale and sandstone, two envelopes are drawn, and the wave impedance corresponding to the intersection of the two envelopes is determined as the threshold value. For example, the threshold value corresponding to the W9 block of the E1 layer is 8800m / s*g / cm3, the threshold value corresponding to the W10 block of the E1 layer is 10200m / s*g / cm3, and the threshold value corresponding to the W19 block of the E1 layer is 10200m / s*g / cm3.

[0050] Step 3: Compare the wave impedance data with the threshold values ​​of the corresponding blocks and layers. If the value is less than or equal to the threshold value, it is shale.

[0051] Specifically, the wave impedance data of the well to be measured is compared with the threshold value of the block and layer where the well to be measured is located. If it is less than or equal to the threshold value, it is shale, and if it is greater than the threshold value, it is sandstone.

[0052] In the above embodiment, the threshold values ​​are divided according to different layers and different blocks, so that shale and sandstone can be identified more accurately.

[0053] Furthermore, since the quantitative relationship between the total organic carbon content and wave impedance in different layers and blocks is established in S2, after the distribution of shale is determined, it is only necessary to substitute the wave impedance data of the shale distribution area into the quantitative relationship corresponding to the block and layer for calculation to obtain the TOC data body.

[0054] In the present invention, after predicting the total organic carbon content of shale and identifying the shale distribution in the predicted area, a high-quality source rock thickness map and a total organic carbon content planar distribution map can also be drawn based on the predicted total organic content and shale distribution.

[0055] It should be understood that shale is a common source rock. The source rock thickness map shows the thickness distribution of the source rock; the TOC plane distribution map shows the content distribution of organic matter in the source rock, and a high TOC value usually indicates a higher hydrocarbon generation potential. Drawing a high-quality source rock thickness map and a total organic carbon content plane distribution map can help determine exploration targets, understand the sedimentary environment, conduct risk assessments, and guide drilling and development, which is of great significance for oil and gas exploration and development.

[0056] Based on the same inventive concept, an embodiment of the present invention also provides a device for predicting the total organic carbon content of shale, the device comprising: The analysis module is used to select shale samples from multiple wells for testing, obtain the total organic carbon content and wave impedance value of the shale, perform correlation analysis on the total organic carbon content and the wave impedance value, and select target wells whose correlation is greater than a preset threshold.

[0057] A construction module is used to obtain the total organic carbon content and wave impedance data of shale from wells in different layers of different blocks in the target well; draw an intersection diagram of the total organic carbon content and wave impedance in different layers of different blocks; and construct a quantitative relationship between the total organic carbon content and wave impedance in different layers of different blocks based on the intersection diagram.

[0058] The prediction module is used to obtain the wave impedance data of the well to be predicted, and predict the shale distribution based on the wave impedance data; substitute the wave impedance data of the shale distribution area into the quantitative relationship corresponding to the block and layer where the shale distribution area is located, and predict the total organic carbon content of the shale.

[0059] Each module in the above-mentioned device for predicting the total organic carbon content of shale can be implemented in whole or in part by software, hardware, or a combination thereof. Each of the above-mentioned modules can be embedded in or independent of a processor in a computer device in the form of hardware, or can be stored in a memory in a computer device in the form of software, so that the processor can call and execute operations corresponding to each of the above modules.

[0060] The present invention also provides a computer device, including a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps in the method embodiment for predicting the total organic carbon content of shale. The specific implementation method can be found in the method embodiment, which will not be described in detail here.

[0061] Furthermore, the present invention also provides a non-temporary computer-readable storage medium containing instructions, and a computer program is stored on the storage medium. For example, a memory containing instructions, the above instructions can be executed by a processor of a computer device to complete the above method. For example, the non-temporary computer-readable storage medium can be a ROM, a random access memory (RAM), a CD-ROM, a magnetic tape, a floppy disk, and an optical data storage device. When the computer program is executed by the processor, the steps in the embodiment of the method for predicting the total organic carbon content of shale can be implemented. The specific implementation method can be found in the method embodiment, which will not be repeated here.

[0062] It should be understood by those skilled in the art that embodiments of the present invention may provide methods, systems or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware aspects. Moreover, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0063] The present invention is described with reference to flowcharts and / or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as a combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0064] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0065] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1A step that specifies a function in one or more boxes.

[0066] It should be pointed out that the specific implementation methods described above can enable those skilled in the art to understand the invention more comprehensively, but do not limit the invention in any way. Therefore, although the invention has been described in detail in this specification and embodiments, those skilled in the art should understand that the invention can still be modified or replaced by equivalents; and all technical solutions and improvements that do not deviate from the spirit and scope of the invention are included in the protection scope of the invention. Any figure mark in the claims should not be regarded as limiting the claims involved. Any simple change or equivalent replacement of the technical solution that can be obviously obtained by any technician familiar with the field within the technical scope disclosed in the present invention belongs to the protection scope of the present invention.

Claims

1. A method for predicting the total organic carbon content of shale, characterized in that: include: Select shale samples from multiple wells for testing, obtain the total organic carbon content and wave impedance value of the shale, perform correlation analysis on the total organic carbon content and wave impedance value, and select target wells where the correlation is greater than a preset threshold; In the target well, the total organic carbon content and wave impedance data of shale from wells in different layers of different blocks are obtained; the intersection diagram of total organic carbon content and wave impedance in different layers of different blocks is drawn; based on the intersection diagram, the quantitative relationship between total organic carbon content and wave impedance in different layers of different blocks is constructed; Obtain the wave impedance data of the well to be predicted, and predict the shale distribution based on the wave impedance data; substitute the wave impedance data of the shale distribution area into the quantitative relationship corresponding to the block and layer where the shale distribution area is located to predict the total organic carbon content of the shale.

2. The method for predicting the total organic carbon content of shale according to claim 1, characterized in that: Predict shale distribution based on wave impedance data, including: Obtain logging data from wells in different layers in different blocks, and draw wave impedance frequency distribution diagrams corresponding to shales with different total organic carbon contents and wave impedance frequency distribution diagrams corresponding to sandstones based on the logging data; According to the wave impedance frequency distribution diagram, the threshold values ​​for distinguishing shale and sandstone in different layers in different blocks are determined; The wave impedance data is compared with the threshold value of the corresponding block and layer. If it is less than or equal to the threshold value, it is mud shale.

3. The method for predicting the total organic carbon content of shale according to claim 1 or 2, characterized in that: Obtain the wave impedance data of the well to be predicted, including: Obtaining density logging curves and acoustic logging curves of the well to be predicted; calculating wave impedance data according to the density logging curves and acoustic logging curves; or, The seismic data of the well to be predicted is obtained, and the wave impedance data is obtained through an inversion algorithm based on the seismic data.

4. The method for predicting the total organic carbon content of shale according to claim 1 or 2, characterized in that: After predicting the shale distribution and total organic carbon content of shale, it also includes: Based on the predicted shale distribution and predicted total organic carbon content, a high-quality source rock thickness map and a planar distribution map of total organic carbon content were drawn.

5. The method for predicting the total organic carbon content of shale according to claim 1 or 2, characterized in that: Many wells are typical wells reflecting the characteristics of source rocks.

6. A device for predicting the total organic carbon content of shale, characterized in that: include: An analysis module is used to select shale samples from multiple wells for testing, obtain the total organic carbon content and wave impedance value of the shale, perform correlation analysis on the total organic carbon content and the wave impedance value, and select target wells where the correlation is greater than a preset threshold; A construction module is used to obtain the total organic carbon content and wave impedance data of shale from wells at different layers in different blocks in the target well; draw the intersection diagram of the total organic carbon content and wave impedance at different layers in different blocks; and construct the quantitative relationship between the total organic carbon content and wave impedance at different layers in different blocks based on the intersection diagram; The prediction module is used to obtain the wave impedance data of the well to be predicted, and predict the shale distribution based on the wave impedance data; substitute the wave impedance data of the shale distribution area into the quantitative relationship corresponding to the block and layer where the shale distribution area is located, and predict the total organic carbon content of the shale.

7. A computer device, characterized in that: The method comprises a memory, a processor and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the method for predicting the total organic carbon content of shale as claimed in any one of claims 1 to 5 is implemented.

8. A computer-readable storage medium, characterized in that: The storage medium stores a computer program, and when the computer program is executed by a processor, the method for predicting the total organic carbon content of shale according to any one of claims 1 to 5 is implemented.

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