Complex structure area shale gas well position optimization method and related device

Abstract

The invention discloses a shale gas well position optimization method in a complex structure area and a related device. The shale gas well position optimization method comprises the steps that the actual average exploratory well thickness, the seismic data prediction shale thickness, the shale gas preservation coefficient and the seismic wave index in the complex structure area are determined; inputting the exploratory well shale actual average thickness, the seismic data predicted shale thickness and the seismic wave index into a high-quality shale development thickness index prediction model to obtain a high-quality shale development thickness index; inputting the high-quality shale development thickness index and the shale gas preservation coefficient into a shale gas enrichment index evaluation model to obtain a shale gas enrichment index; and shale gas well position optimization is carried out according to the shale gas enrichment index. The method aims at improving the shale gas exploration success rate in the complex structure area.

Description

Technical Field

[0001] This invention belongs to the field of petroleum exploration and development technology, specifically relating to a method and related apparatus for optimizing shale gas well locations in complex structural areas. Background Technology

[0002] Shale gas is an important unconventional oil and gas resource and a crucial successor area for future oil and gas reserve and production growth. Early shale gas exploration mainly targeted structurally stable areas within basins, with well location selection primarily focusing on the source rock and reservoir conditions. As shale gas exploration and development continue to deepen, exploration is gradually moving towards structurally complex areas.

[0003] Complex tectonic zones generally refer to areas where multiple phases of tectonic activity occurred during the sedimentary and burial periods, resulting in diverse geological structures and well-developed faults. Domestic and international exploration experience shows that faults significantly impact the enrichment of shale gas. Although shale in complex tectonic zones contains gas over large areas, enrichment occurs only locally, leading to significant variations in single-well production and generally low exploration success rates. Therefore, a comprehensive evaluation method for optimizing shale gas well locations in complex tectonic zones is urgently needed.

[0004] Current methods for shale gas well location optimization, such as the invention patent with publication number CN115045646A, provide a method for shale gas well location optimization. This method uses GR curves to predict target shale layers and constructs a fitting relationship between total organic carbon content and density based on well logging data (resistivity, acoustic wave, density) and measured geochemical data. Then, it calculates the total organic carbon content data volume of the study area based on seismic inversion density data to predict the spatial distribution of effective shale gas development intervals (TOC > 2.0%), and optimizes well locations by combining formation pressure characteristics. This method quantitatively predicts the distribution of high-quality shale and optimizes well locations. However, this method is mainly for shale gas well location optimization in stable structural areas and does not consider structural factors. For complex structural areas, shale gas enrichment is mainly affected by the development and distribution of high-quality shale and the control of the gas reservoir by the structure. Therefore, this method is not suitable for shale gas well location optimization in complex structural areas. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a method and related apparatus for optimizing shale gas well locations in complex structural areas, with the aim of improving the success rate of shale gas exploration in complex structural areas.

[0006] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution:

[0007] A method for optimizing shale gas well locations in complex geological formations includes:

[0008] Determine the actual average thickness of shale in exploration wells within complex structural zones, the shale thickness predicted by seismic data, the shale gas preservation coefficient, and the seismic wave index;

[0009] The actual average thickness of the shale in the exploration well, the shale thickness predicted by the seismic data, and the seismic wave index are input into the high-quality shale development thickness index prediction model to obtain the high-quality shale development thickness index.

[0010] The high-quality shale development thickness index and the shale gas preservation coefficient are input into the shale gas enrichment index evaluation model to obtain the shale gas enrichment index;

[0011] Shale gas well locations are selected based on the shale gas enrichment index.

[0012] Furthermore, the method for determining the actual average thickness of the shale in the exploration well is as follows:

[0013] Determine the number of exploration wells and the sum of the actual thickness of the shale in the exploration wells within the complex structural zone;

[0014] The actual average thickness of the shale in each exploration well is obtained by dividing the sum of the actual thicknesses of the shale in the exploration wells by the number of exploration wells.

[0015] Furthermore, the methods for predicting shale thickness and determining the seismic wave index based on the seismic data are as follows:

[0016] Acquire seismic data in complex tectonic zones;

[0017] The seismic data is used to identify the top and bottom interfaces of the strata, thereby obtaining the predicted shale thickness based on the seismic data;

[0018] The seismic wave index is determined using the seismic data.

[0019] Furthermore, the method for determining the shale gas preservation coefficient is as follows:

[0020] Acquire seismic data in complex tectonic zones;

[0021] Fault interpretation of the seismic profile was carried out based on the aforementioned seismic data;

[0022] The faults in the seismic profile were interpreted in stages, distinguishing between syn-depositional faults and late-stage faults. Faults contemporaneous with the target layer were syn-depositional faults, while faults formed after the depositional period were late-stage faults.

[0023] For the fractures that have been explained, a fracture plane distribution map is generated, and the fracture stages are marked;

[0024] Based on the fracture plane distribution map, the shale gas preservation coefficient D is... f Assignment, specifically including:

[0025] (1) For complex tectonic zones where only syn-sedimentary faults are developed, D f =1;

[0026] (2) For complex tectonic zones where both syn-sedimentary faults and late-stage faults are simultaneously developed, including:

[0027] Fault distance > 5km, D f =1;

[0028] 5km > fracture distance > 3km, D f =0.9;

[0029] 3km > fracture distance > 1km, D f =0.8;

[0030] 1km>Fault distance, D f =0.

[0031] Furthermore, the prediction model for the thickness index of high-quality shale development is as follows:

[0032]

[0033] In the formula, H is the thickness index of high-quality shale development; λ is the seismic wave index; H for To predict shale thickness from seismic data; H ave This represents the actual average thickness of the shale in the exploration well.

[0034] Furthermore, the shale gas enrichment index evaluation model is as follows:

[0035] S = H × 0.3 + D f ×0.7

[0036] In the formula, S is the shale gas enrichment index; H is the thickness index of high-quality shale development; D f This represents the shale gas preservation coefficient.

[0037] Furthermore, the step of selecting shale gas well locations based on the shale gas enrichment index specifically involves:

[0038] The shale gas enrichment index is compared with a set shale gas enrichment index threshold, and the area corresponding to the shale gas enrichment index that is greater than the set shale gas enrichment index threshold is selected as the preferred shale gas well location.

[0039] A device for optimizing shale gas well locations in complex geological formations includes:

[0040] The determination module is used to determine the actual average thickness of shale in exploration wells, the shale thickness predicted by seismic data, the shale gas preservation coefficient, and the seismic wave index in complex structural areas.

[0041] The prediction module is used to input the actual average thickness of the shale in the exploration well, the predicted shale thickness from the seismic data, and the seismic wave index into the high-quality shale development thickness index prediction model to obtain the high-quality shale development thickness index.

[0042] The evaluation module is used to input the high-quality shale development thickness index and the shale gas preservation coefficient into the shale gas enrichment index evaluation model to obtain the shale gas enrichment index.

[0043] The selection module is used to optimize shale gas well locations based on the shale gas enrichment index.

[0044] An apparatus includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method for optimizing shale gas well locations in complex structural areas.

[0045] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the steps of the method for optimizing shale gas well locations in complex structural areas.

[0046] Compared with the prior art, the present invention has at least the following beneficial effects:

[0047] This invention provides a method for optimizing shale gas well locations in complex structural areas. It utilizes the actual average thickness of shale in exploration wells, predicts shale thickness based on seismic data, and establishes seismic wave indices. A high-quality shale development thickness index is obtained by combining this with a high-quality shale development thickness index prediction model. Furthermore, a shale gas enrichment index is obtained by combining the high-quality shale development thickness index and the shale gas preservation coefficient with a shale gas enrichment index evaluation model. Both the high-quality shale development thickness index prediction model and the shale gas enrichment index evaluation model comprehensively consider multiple factors such as shale thickness, seismic wave characteristics, and shale gas preservation, accurately reflecting the degree of shale gas enrichment. Optimizing shale gas well locations based on the shale gas enrichment index can guide the rational layout of shale gas exploration and development, enabling optimal shale gas well location selection in complex structural areas and providing a scientific basis for shale gas exploration and development. In other words, based on the analysis of the main controlling factors of shale gas enrichment, the range of favorable areas is quantitatively evaluated through the prediction model of the thickness index of high-quality shale development and the evaluation model of shale gas enrichment index, so as to carry out the optimization of shale gas well location deployment and effectively improve the success rate of shale gas exploration in complex structural areas.

[0048] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0049] To more clearly illustrate the technical solutions in the specific embodiments of the present invention, the drawings used in the description of the specific embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0050] Figure 1 This is a flowchart of a method for optimizing shale gas well locations in complex geological formations according to the present invention;

[0051] Figure 2 This is a schematic diagram of the fault interpretation carried out on the seismic profile in Example 1. The red lines in the diagram represent syn-sedimentary faults.

[0052] Figure 3 This is a schematic diagram of the fault interpretation carried out on the seismic profile in Example 2. In the diagram, red represents syn-sedimentary faults and blue represents late-stage faults. Detailed Implementation

[0053] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0054] Combination Figure 1 As shown in the figure, this application provides a method for optimizing shale gas well locations in complex structural zones, specifically including the following steps:

[0055] Step 1: Determine the actual average thickness of shale in exploration wells within complex structural zones, the shale thickness predicted by seismic data, the shale gas preservation coefficient, and the seismic wave index.

[0056] In one embodiment, the method for determining the actual average thickness of the shale in the exploration well is as follows:

[0057] First, determine the number of exploratory wells and the sum of the actual thickness of the shale in the exploratory wells within the complex geological structure. Specifically, this is done by reviewing geological data and drilling reports.

[0058] Finally, the actual average thickness of the shale in the exploration wells is obtained by dividing the sum of the actual thicknesses of the shale in the exploration wells by the number of exploration wells.

[0059] In one embodiment, the method for determining shale thickness and seismic wave index based on seismic data is as follows:

[0060] First, acquire seismic data within complex tectonic zones.

[0061] It should be understood that seismic data in complex tectonic zones includes key information such as seismic profiles and stratigraphic identification.

[0062] Finally, the top and bottom interfaces of the strata are identified using seismic data, thereby predicting the shale thickness. Simultaneously, seismic wave indices are determined using the seismic data. These indices reflect the propagation characteristics of seismic waves within the shale layers and are of significant importance for predicting the thickness of high-quality shale formations.

[0063] It should be understood that the seismic wave index is mainly based on the intensity of seismic reflected waves and is assigned a value artificially.

[0064] For example, if the earthquake reflection wave is strong, the seismic wave index is assigned a value of 1; if the earthquake reflection wave is of medium intensity, the seismic wave index is assigned a value of 0.9; and if the earthquake reflection wave is of weak intensity, the seismic wave index is assigned a value of 0.8.

[0065] In one embodiment, the method for determining the shale gas preservation coefficient is as follows:

[0066] a. Based on seismic data, perform fault interpretation on seismic profiles to identify fault locations and types.

[0067] b. Conduct phased interpretation of the faults in the seismic profile, distinguishing between syn-depositional faults and late-stage faults. Faults contemporaneous with the target layer are syn-depositional faults, while faults formed after the depositional period are late-stage faults.

[0068] c. For the explained fractures, create a fracture plane distribution map and indicate the fracture stages;

[0069] d. Based on the fracture plane distribution map, the shale gas preservation coefficient D f Assigning values ​​specifically includes:

[0070] (1) For complex tectonic zones where only syn-sedimentary faults are developed, D f =1;

[0071] (2) For complex tectonic zones with both syn-sedimentary faults and late-stage faults, the shale gas preservation coefficient varies between 0 and 1 depending on the fault distance. Specifically:

[0072] Fault distance > 5km, D f =1;

[0073] 5km > fracture distance > 3km, D f =0.9;

[0074] 3km > fracture distance > 1km, D f =0.8;

[0075] 1km>Fault distance, D f =0.

[0076] Before deploying exploratory wells, there is little geological data available for reference, but seismic data is relatively cheaper than exploratory well drilling and can be obtained over a large area.

[0077] Step 2: Input the actual average thickness of the shale in the exploration well, the predicted shale thickness from seismic data, and the seismic wave index into the high-quality shale development thickness index prediction model to obtain the high-quality shale development thickness index.

[0078] Specifically, the prediction model for the thickness index of high-quality shale development is as follows:

[0079]

[0080] In the formula, H is the thickness index of high-quality shale development; λ is the seismic wave index; H for To predict shale thickness from seismic data; H ave This represents the actual average thickness of the shale in the exploration well.

[0081] Step 3: Input the high-quality shale development thickness index and shale gas preservation coefficient into the shale gas enrichment index evaluation model to obtain the shale gas enrichment index.

[0082] It should be noted that the higher the shale gas enrichment index in a complex tectonic zone, the more favorable it is for shale gas enrichment.

[0083] Specifically, the shale gas enrichment index evaluation model is as follows:

[0084] S = H × 0.3 + D f ×0.7

[0085] In the formula, S is the shale gas enrichment index; H is the thickness index of high-quality shale development; D f This represents the shale gas preservation coefficient.

[0086] Step 4: Optimize shale gas well locations based on shale gas enrichment index.

[0087] In one embodiment, the shale gas enrichment index is compared with a set shale gas enrichment index threshold, and the area corresponding to the shale gas enrichment index that is greater than the set shale gas enrichment index threshold is selected as the preferred shale gas well location.

[0088] For example, the method for setting the shale gas enrichment index threshold can be as follows: Enrichment index statistics are conducted on drilled wells to determine the shale gas enrichment index standard. Specifically, for industrial gas flow wells, the enrichment index is calculated, and the lowest value is taken as the lower limit of the shale gas enrichment index standard (i.e., the shale gas enrichment index threshold). Areas above this value are considered favorable zones, and the favorable zone is then drawn on a plane as the preferred shale gas well locations.

[0089] This invention comprehensively considers the enrichment and preservation of shale gas in complex structural areas, and can guide the rational layout of shale gas exploration and development. Through the above steps, this method can optimize the location of shale gas wells in complex structural areas, providing a scientific basis for shale gas exploration and development.

[0090] The two models comprehensively consider multiple factors such as shale thickness, seismic wave characteristics, and shale gas preservation, and can accurately reflect the enrichment degree of shale gas. They can effectively delineate favorable exploration areas and achieve the goal of optimizing well locations in complex structural areas.

[0091] In one embodiment, the accuracy of the method is verified using drilled wells in the study area. Specifically, one successful well and one unsuccessful well are selected, and the shale gas enrichment index is calculated for each. The shale gas enrichment indexes of the two wells are compared to determine whether the shale gas well location optimization method in this complex structural area is accurate.

[0092] Example 1

[0093] The method for optimizing the location of well A1 includes the following steps:

[0094] (1) Data collection and processing, mainly including seismic data in the study area, actual shale thickness in exploration wells, and shale thickness predicted by seismic data;

[0095] (2) Using the data prepared in step (1), predict the thickness index of high-quality shale development:

[0096] First, by dividing the sum of the actual shale thicknesses of the exploration wells in the study area by the number of exploration wells, we obtain the average shale thickness in the study area as 43.6 meters.

[0097] Then, the top and bottom interfaces of the strata were identified using seismic data, and the shale thickness predicted by the seismic data was obtained as 33 meters.

[0098] Finally, using the high-quality shale development thickness index prediction model, the high-quality shale development thickness index is predicted as follows: H = 1 × 33 ÷ 43.6 = 0.76.

[0099] (3) Conduct shale gas preservation coefficient prediction

[0100] First, refer to Figure 2 Fault interpretation was carried out on the seismic profile through well A1;

[0101] Then, the faults interpreted from the seismic profiles were divided into stages. Faults contemporaneous with the target layer were classified as co-depositional faults, while faults formed after the depositional period were classified as late-stage faults.

[0102] Finally, the shale gas preservation coefficient was assigned a value of D, as only syn-sedimentary faults were developed in the area near well A1. f =1;

[0103] (4) Calculate the shale gas enrichment index to determine whether it is within the sweet spot area.

[0104] First, the shale gas enrichment index S is calculated as S = 0.76 × 0.3 + 1 × 0.7 = 0.928;

[0105] Secondly, the standard for shale gas enrichment index was determined. The enrichment index of 7 industrial gas flow wells in the study area was calculated. The lowest value was 0.73, and the threshold value of shale gas enrichment index was taken as 0.73.

[0106] Finally, it was determined whether well A1 was within the sweet spot area: 0.928 > 0.73, therefore it was within the sweet spot area. The final test gas production was 152,200 cubic meters per day, and the determination was accurate.

[0107] Example 2

[0108] The method for optimizing the location of well A2 includes the following steps:

[0109] (1) Data collection and processing, mainly including seismic data in the study area, actual shale thickness in exploration wells, and shale thickness predicted by seismic data;

[0110] (2) Using the data prepared in step (1), predict the thickness index of high-quality shale development:

[0111] First, by dividing the sum of the actual shale thicknesses of the exploration wells in the study area by the number of exploration wells, we obtain the average shale thickness in the study area as 43.6 meters.

[0112] Then, the top and bottom interfaces of the strata were identified using seismic data, and the shale thickness predicted by the seismic data was obtained as 26 meters.

[0113] Finally, using the high-quality shale development thickness index prediction model, the high-quality shale development thickness index is predicted as follows: H = 1 × 26 ÷ 43.6 = 0.59.

[0114] (3) Conduct shale gas preservation coefficient prediction

[0115] First, refer to Figure 3 Fault interpretation was carried out on the seismic profile of well A2;

[0116] Then, the faults interpreted from the seismic profiles were divided into stages. Faults contemporaneous with the target layer were classified as co-depositional faults, while faults formed after the depositional period were classified as late-stage faults.

[0117] Finally, the shale gas preservation coefficient was assigned a value. In the area near well A2, syn-sedimentary faults and late-stage faults developed simultaneously and were interconnected, with a fault distance of 300 meters. The coefficient was assigned the value D. f =0;

[0118] (4) Calculate the shale gas enrichment index to determine whether it is within the sweet spot area.

[0119] First, the shale gas enrichment index S is calculated as S = 0.59 × 0.3 + 0 × 0.7 = 0.18;

[0120] Secondly, the standard for shale gas enrichment index was determined. The enrichment index of 7 industrial gas flow wells in the study area was calculated. The lowest value was 0.73, and the threshold value of shale gas enrichment index was taken as 0.73.

[0121] Finally, it was determined whether well A2 was within the sweet spot area: 0.18 < 0.73, therefore it was not within the sweet spot area. The final test gas production was 0.15 million cubic meters per day, and the determination was accurate.

[0122] In one embodiment of the present invention, a device for optimizing shale gas well locations in complex structural zones is provided, comprising:

[0123] The determination module is used to determine the actual average thickness of shale in exploration wells within complex structural zones, the shale thickness predicted by seismic data, the shale gas preservation coefficient, and the seismic wave index.

[0124] The prediction module is used to input the actual average thickness of the shale in the exploration well, the predicted shale thickness from the seismic data, and the seismic wave index into the high-quality shale development thickness index prediction model to obtain the high-quality shale development thickness index.

[0125] The evaluation module is used to input the high-quality shale development thickness index and the shale gas preservation coefficient into the shale gas enrichment index evaluation model to obtain the shale gas enrichment index.

[0126] The selection module is used to optimize shale gas well locations based on the shale gas enrichment index.

[0127] The specific implementation methods of the above modules can be found in the relevant content disclosed in the foregoing embodiments, and will not be repeated here.

[0128] In one embodiment of the present invention, a computer device is provided, comprising a processor and a memory. The memory stores a computer program, which includes program instructions. The processor executes the program instructions stored in the computer storage medium. The processor may be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing and control core of the terminal, suitable for implementing one or more instructions, specifically suitable for loading and executing one or more instructions to achieve a corresponding method flow or corresponding function. The processor described in this embodiment of the present invention can be used to implement an operation of a method for optimizing shale gas well locations in complex structural areas.

[0129] In one embodiment of the present invention, a method for optimizing shale gas well locations in complex structural areas, if implemented as a software functional unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on this understanding, all or part of the processes in the methods of the above embodiments of the present invention can also be implemented by a computer program instructing related hardware. The computer program can be stored in a computer-readable storage medium, and when executed by a processor, it can implement the steps of the various method embodiments described above. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or certain intermediate forms. The computer-readable storage medium includes permanent and non-permanent, removable and non-removable media, and information storage can be implemented by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data.

[0130] The computer storage medium can be any available medium or data storage device that a computer can access, including but not limited to magnetic storage (e.g., floppy disks, hard disks, magnetic tapes, magneto-optical disks (MOs)), optical storage (e.g., CDs, DVDs, BDs, HVDs), and semiconductor storage (e.g., ROMs, EPROMs, EEPROMs, non-volatile memory (NAND flash), solid-state drives (SSDs)).

[0131] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied 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.

[0132] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create a machine for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0133] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0134] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0135] In the description of this invention, it should be understood that the terms "upper", "lower", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0136] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0137] In this invention, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0138] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0139] In this invention, the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to a specific feature, structure, material, or characteristic described in connection with that embodiment or example, which is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0140] Finally, it should be noted that the above-described embodiments are merely specific implementations of the present invention, used to illustrate the technical solutions of the present invention, and not to limit it. The scope of protection of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments within the technical scope disclosed in the present invention, or make equivalent substitutions for some of the technical features; and these modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for optimizing shale gas well locations in complex geological formations, characterized in that, include: Determine the actual average thickness of shale in exploration wells within complex structural zones, the shale thickness predicted by seismic data, the shale gas preservation coefficient, and the seismic wave index; The actual average thickness of the shale in the exploration well, the shale thickness predicted by the seismic data, and the seismic wave index are input into the high-quality shale development thickness index prediction model to obtain the high-quality shale development thickness index. The high-quality shale development thickness index and the shale gas preservation coefficient are input into the shale gas enrichment index evaluation model to obtain the shale gas enrichment index; Shale gas well locations are selected based on the shale gas enrichment index.

2. The method for optimal shale gas well location selection in complex structural zones according to claim 1, characterized in that, The method for determining the actual average thickness of the shale in the exploration well is as follows: Determine the number of exploration wells and the sum of the actual thickness of the shale in the exploration wells within the complex structural zone; The actual average thickness of the shale in each exploration well is obtained by dividing the sum of the actual thicknesses of the shale in the exploration wells by the number of exploration wells.

3. The method for optimal shale gas well location selection in complex structural zones according to claim 1, characterized in that, The methods for predicting shale thickness and determining the seismic wave index based on the seismic data are as follows: Acquire seismic data in complex tectonic zones; The seismic data is used to identify the top and bottom interfaces of the strata, thereby obtaining the predicted shale thickness based on the seismic data; The seismic wave index is determined using the seismic data.

4. The method for optimal shale gas well location selection in complex structural zones according to claim 1, characterized in that, The method for determining the shale gas preservation coefficient is as follows: Acquire seismic data in complex tectonic zones; Fault interpretation of the seismic profile was carried out based on the aforementioned seismic data; The faults in the seismic profile were interpreted in stages, distinguishing between syn-depositional faults and late-stage faults. Faults contemporaneous with the target layer were syn-depositional faults, while faults formed after the depositional period were late-stage faults. For the fractures that have been explained, a fracture plane distribution map is generated, and the fracture stages are marked; Based on the fracture plane distribution map, the shale gas preservation coefficient D is... f Assignment, specifically including: (1) For complex tectonic zones where only syn-sedimentary faults are developed, D f =1; (2) For complex tectonic zones where both syn-sedimentary faults and late-stage faults are simultaneously developed, including: Fault distance > 5km, D f =1; 5km > fracture distance > 3km, D f =0.9; 3km > fracture distance > 1km, D f =0.8; 1km>Fault distance, D f =0.

5. The method for optimal shale gas well location selection in complex structural zones according to claim 1, characterized in that, The prediction model for the thickness index of high-quality shale development is as follows: In the formula, H is the thickness index of high-quality shale development; λ is the seismic wave index; H for To predict shale thickness from seismic data; H ave This represents the actual average thickness of the shale in the exploration well.

6. The method for optimal shale gas well location selection in complex structural zones according to claim 1, characterized in that, The shale gas enrichment index evaluation model is as follows: S = H × 0.3 + Df × 0.7 In the formula, S is the shale gas enrichment index; H is the thickness index of high-quality shale development; D f This represents the shale gas preservation coefficient.

7. The method for optimal shale gas well location selection in complex structural zones according to claim 1, characterized in that, The step of selecting optimal shale gas well locations based on the shale gas enrichment index specifically involves: The shale gas enrichment index is compared with a set shale gas enrichment index threshold, and the area corresponding to the shale gas enrichment index that is greater than the set shale gas enrichment index threshold is selected as the preferred shale gas well location.

8. A device for optimizing shale gas well locations in complex geological formations, characterized in that, include: The determination module is used to determine the actual average thickness of shale in exploration wells, the shale thickness predicted by seismic data, the shale gas preservation coefficient, and the seismic wave index in complex structural areas. The prediction module is used to input the actual average thickness of the shale in the exploration well, the predicted shale thickness from the seismic data, and the seismic wave index into the high-quality shale development thickness index prediction model to obtain the high-quality shale development thickness index. The evaluation module is used to input the high-quality shale development thickness index and the shale gas preservation coefficient into the shale gas enrichment index evaluation model to obtain the shale gas enrichment index. The selection module is used to optimize shale gas well locations based on the shale gas enrichment index.

9. An apparatus comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the steps of the method for selecting the best shale gas well location in a complex structural area as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the method for selecting the best shale gas well location in a complex structural zone as described in any one of claims 1 to 7.

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