Fracturing potential evaluation index determination method and device, medium and electronic equipment

Abstract

The invention discloses a fracturing potential evaluation index determination method and device, a medium and electronic equipment. The method comprises the following steps: calculating a quality index of a coal bed gas reservoir, wherein the quality index of the coal bed gas reservoir is obtained by calculating coal bed gas saturation, coal bed thickness, coal bed permeability and coal bed total porosity corresponding to the coal bed gas reservoir; calculating a coal bed gas reservoir engineering quality index, wherein the coal bed gas reservoir engineering quality index is obtained by calculating a coal body structure index, a coal bed stress index, a ratio of ash content to fixed carbon content and a fracture pressure gradient corresponding to the coal bed gas reservoir; and calculating a fracturing potential evaluation index corresponding to the coalbed methane reservoir according to the coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index. According to the method, the accuracy of calculating the fracturing potential evaluation index can be improved.

Description

Background Art

[0002] At present, there are huge differences between coalbed methane reservoirs and conventional sandstone and carbonate reservoirs. Deep coalbed methane reservoirs also differ significantly from medium and shallow coalbed methane reservoirs in coal rock composition, coal body structure and mechanical properties. The existing reservoir fracturing potential evaluation method is not suitable for coalbed methane reservoirs. For coalbed methane reservoirs, how to improve the accuracy of calculating the fracturing potential evaluation index is a technical problem that needs to be solved urgently. Summary of the invention

[0003] The purpose of the present application is to provide a method, device, medium and electronic device for determining a fracturing potential evaluation index. The present application can improve the accuracy of calculating a fracturing potential evaluation index.

[0004] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by the practice of the present application.

[0005] According to one aspect of an embodiment of the present application, a method for determining a fracturing potential evaluation index is provided, characterized in that the method includes: calculating a coalbed methane reservoir quality index, wherein the coalbed methane reservoir quality index is calculated by the gas saturation of the coal seam, the coal seam thickness, the coal seam permeability and the total porosity of the coal seam corresponding to the coalbed methane reservoir; calculating a coalbed methane reservoir engineering quality index, wherein the coalbed methane reservoir engineering quality index is calculated by the coal body structure index, the coal seam stress index, the ratio of ash to fixed carbon content, and the fracture pressure gradient corresponding to the coalbed methane reservoir; and calculating the fracturing potential evaluation index corresponding to the coalbed methane reservoir based on the coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index.

[0006] In one embodiment of the present application, based on the aforementioned scheme, after the fracturing potential evaluation index is calculated, the fracturing potential of the coalbed methane reservoir is evaluated based on the fracturing potential evaluation index, including: if the fracturing potential evaluation index is greater than a first threshold value, then it is determined that the coalbed methane reservoir is an easy-to-transform reservoir, and the coalbed methane reservoir forms a network of fractures after fracturing, and the coalbed methane reservoir is a high-yield reservoir.

[0007] In one embodiment of the present application, based on the aforementioned scheme, after the fracturing potential evaluation index is calculated, the fracturing potential of the coalbed methane reservoir is evaluated based on the fracturing potential evaluation index, including: if the fracturing potential evaluation index is greater than a second threshold value and less than a first threshold value, then it is determined that the coalbed methane reservoir is a medium-transformed reservoir, and that the coalbed methane reservoir forms partial fractures after fracturing, and that the coalbed methane reservoir is a low-yield reservoir.

[0008] In one embodiment of the present application, based on the foregoing solution, after calculating the fracturing potential evaluation index, the fracturing potential of the coalbed methane reservoir is evaluated based on the fracturing potential evaluation index, including: if the fracturing potential evaluation index is less than the second threshold, it is determined that the coalbed methane reservoir is a difficult-to-transform reservoir, and no effective fracture can be formed in the coalbed methane reservoir, and the production of the coalbed methane reservoir is lower than the minimum industrial production.

[0009] In one embodiment of the present application, based on the foregoing solution, the coalbed methane reservoir quality index is calculated by the following formula, including:

[0010]

[0011] wherein, I R is the coalbed methane reservoir quality index, dimensionless; S g is the gas saturation of the coal seam, %; H c is the coal seam thickness, m; K c is the coal seam permeability, 10 -3 μm 2 ; is the total porosity of the coal seam, %.

[0012] In one embodiment of the present application, based on the foregoing solution, the coalbed methane reservoir engineering quality index is calculated by the following formula, including:

[0013]

[0014] wherein, I C is the coalbed methane reservoir engineering quality index, dimensionless; I cs is the coal body structure index, dimensionless; I σ is the coal seam stress index, dimensionless; R af is the ratio of ash content to fixed carbon content, dimensionless; G pf is the fracture pressure gradient of the coal seam, MPa / m.

[0015] In one embodiment of the present application, based on the foregoing solution, the fracturing potential evaluation index is calculated by the following formula, including:

[0016] I pf = I R × I C

[0017] wherein, I pf is the fracturing potential evaluation index, dimensionless; I R is the coalbed methane reservoir quality index, dimensionless; I C is the coalbed methane reservoir engineering quality index, dimensionless.

[0018] According to one aspect of the embodiments of the present application, there is provided a device for determining a fracturing potential evaluation index, characterized in that the device includes: a first calculation unit for calculating a coalbed methane reservoir quality index, which is calculated by the gas saturation, coal seam thickness, coal seam permeability and total porosity of the coal seam corresponding to the coalbed methane reservoir; a second calculation unit for calculating a coalbed methane reservoir engineering quality index, which is calculated by the coal body structure index, coal seam stress index, ratio of ash content to fixed carbon content, and fracture pressure gradient corresponding to the coalbed methane reservoir; and a third calculation unit for calculating a fracturing potential evaluation index corresponding to the coalbed methane reservoir according to the coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index.

[0019] According to one aspect of the embodiments of the present application, there is provided a computer-readable storage medium with a computer program stored thereon, the computer program including executable instructions, which, when executed by a processor, implement the method described in the above embodiments.

[0020] According to one aspect of the embodiments of the present application, there is provided an electronic device, including: one or more processors; a memory for storing executable instructions of the processor, which, when executed by the one or more processors, cause the one or more processors to implement the method described in the above embodiments.

[0021] In the present application, first, according to the logging data corresponding to the coalbed methane reservoir, the gas saturation, coal seam thickness, coal seam permeability and total porosity of the coal seam corresponding to the coalbed methane reservoir are obtained. According to the gas saturation, coal seam thickness, coal seam permeability and total porosity of the coal seam, the coalbed methane reservoir quality index is calculated.

[0022] Then, according to the logging data corresponding to the coalbed methane reservoir, the coal body structure index, coal seam stress index, ratio of ash content to fixed carbon content, and fracture pressure gradient are obtained. According to the coal body structure index, coal seam stress index, ratio of ash content to fixed carbon content, and fracture pressure gradient, the coalbed methane reservoir engineering quality index is calculated.

[0023] According to the calculated coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index, the fracturing potential evaluation index is calculated. Based on the fracturing potential evaluation index, the coal seams in the coalbed methane reservoir can be classified, so as to screen out coal seams with high coalbed methane content and low coal seam development difficulty.

[0024] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings here are incorporated into the specification and form a part of this specification, showing embodiments consistent with this application, and are used together with the specification to explain the principles of this application. Obviously, the accompanying drawings in the following description are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings. In the drawings:

[0026] Figure 1 is a flowchart of a method for determining a fracturing potential evaluation index shown according to an embodiment of this application;

[0027] Figure 2 is a graph showing the evaluation results of the fracturing potential of a coalbed methane reservoir shown according to an embodiment of this application;

[0028] Figure 3 is a block diagram of a device for determining a fracturing potential evaluation index shown according to an embodiment of this application;

[0029] Figure 4 is a schematic diagram of the system structure of an electronic device shown according to an embodiment of this application. Detailed Embodiments

[0030] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be more complete and comprehensive, and will fully convey the concept of the example embodiments to those skilled in the art.

[0031] In addition, the described features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of the embodiments of this application. However, those skilled in the art will realize that the technical solutions of this application can be practiced without one or more of the specific details, or other methods, components, devices, steps, etc. can be adopted. In other cases, well-known methods, devices, implementations, or operations are not shown or described in detail to avoid obscuring aspects of this application.

[0032] The block diagrams shown in the accompanying drawings are only functional entities and do not necessarily correspond to physically independent entities. That is, these functional entities can be implemented in software form, or implemented in one or more hardware modules or integrated circuits, or implemented in different networks and / or processor devices and / or microcontroller devices.

[0033] The flowcharts shown in the accompanying drawings are only illustrative and not necessarily include all content and operations / steps, nor are they necessarily executed in the described order. For example, some operations / steps can be decomposed, while some operations / steps can be combined or partially combined, so the actual execution order may change according to the actual situation.

[0034] It should be noted that: "a plurality" as mentioned in this article refers to two or more. "And / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. The character " / " generally represents an "or" relationship between the associated objects before and after.

[0035] The implementation details of the technical solutions of the embodiments of the present application are elaborated in detail below:

[0036] According to one aspect of the present application, a method for determining a fracturing potential evaluation index is provided. Figure 1 FIG. is a flowchart of a method for determining a fracturing potential evaluation index shown according to an embodiment of the present application. The method for determining the fracturing potential evaluation index can be executed by a device with computing and processing functions. The method for determining the fracturing potential evaluation index at least includes steps 110 to 130, which are introduced in detail as follows:

[0037] In step 110, calculate the coalbed methane reservoir quality index, and the coalbed methane reservoir quality index is calculated through the coalbed gas saturation, coal seam thickness, coal seam permeability, and total porosity of the coalbed methane reservoir corresponding to the coal seam.

[0038] In the present application, first, according to the logging data corresponding to the coalbed methane reservoir, obtain the coalbed gas saturation, coal seam thickness, coal seam permeability, and total porosity of the coalbed methane reservoir corresponding to the coal seam. Then, based on the coalbed gas saturation, the coal seam thickness, the coal seam permeability, and the total porosity, calculate the coalbed methane reservoir quality index. Among them, the coalbed methane reservoir quality index can be used to evaluate the reservoir quality of the coal seam in the coalbed methane reservoir, that is, the development potential of the coalbed methane in the coal seam can be analyzed.

[0039] Furthermore, the coalbed methane reservoir quality index can be calculated by the following formula:

[0040]

[0041] Wherein, I R is the coalbed methane reservoir quality index, dimensionless; S g is the coalbed gas saturation, %; H c is the coal seam thickness, m; K c is the coal seam permeability, 10 -3 μm2 ; is the total porosity of the coal seam, %.

[0042] Specifically, the gas saturation of the coal seam can be calculated by the following formula:

[0043] S g = (V g / V L )(P L + P) / P

[0044] where S g is the gas saturation of the coal seam, %; V g is the gas content of the coal seam calculated by logging, m 3 / t; V L is the theoretical gas content, that is, the gas volume adsorbed when adsorption reaches saturation, also known as the Langmuir volume, m 3 / t; P L is the pressure when the adsorption amount reaches 50% of the saturated adsorption amount, also known as the Langmuir pressure, MPa; P is the coal reservoir pressure, MPa.

[0045] The thickness of the coal seam can be calculated by the following formula:

[0046] H ce = H c - H g

[0047] where H ce is the effective thickness of the coal seam, m; H c is the thickness of the coal seam, m; H g is the thickness of coal gangue, m.

[0048] The total porosity of the coal seam can be calculated by the following formula:

[0049]

[0050] where, is the total porosity of the coal seam, %; is the density porosity, %; is the acoustic porosity, %.

[0051] The permeability of the coal seam can be calculated by the following formula:

[0052]

[0053] where K c is the permeability of the coal seam, 10 -3 μm 2 ; S φ is the specific surface area of coal, cm 2 / cm3 ; k is the Gaussini constant.

[0054] Continue to refer to Figure 1 , in step 120, calculate the engineering quality index of the coalbed methane reservoir, and the engineering quality index of the coalbed methane reservoir is obtained by calculating the coal body structure index, coal seam stress index, ratio of ash content to fixed carbon content, and fracture pressure gradient corresponding to the coalbed methane reservoir.

[0055] In this application, first, according to the logging data corresponding to the coalbed methane reservoir, obtain the coal body structure index, coal seam stress index, and ratio of ash content to fixed carbon content corresponding to the coalbed methane reservoir. Then, based on the coal body structure index, the coal seam stress index, and the ratio of ash content to fixed carbon content, calculate the engineering quality index of the coalbed methane reservoir. Among them, the engineering quality index of the coalbed methane reservoir can be used to evaluate the engineering quality of the coal seam in the coalbed methane reservoir, that is, the development difficulty corresponding to the coal seam can be analyzed.

[0056] Furthermore, the engineering quality index of the coalbed methane reservoir can be calculated by the following formula:

[0057]

[0058] where, I C is the engineering quality index of the coalbed methane reservoir, dimensionless; I cs is the coal body structure index, dimensionless; I σ is the coal seam stress index, dimensionless; R af is the ratio of ash content to fixed carbon content, dimensionless; G pf is the fracture pressure gradient of the coal seam, MPa / m.

[0059] Specifically, the coal body structure index can be calculated by the following formula:

[0060]

[0061] where, I CS is the coal body structure index, dimensionless; ρ b is the compensated density, g / cm 3 ; Δt is the acoustic travel time, μs / ft; Rt is the resistivity, Ω·m.

[0062] The coal seam stress index can be calculated by the following formula:

[0063]

[0064] where, I σ is the coal seam stress index, dimensionless; K His the stress difference coefficient of the coal seam, dimensionless; Δσ is the minimum horizontal principal stress difference between the coal seam and its roof and floor, MPa.

[0065] The ratio of ash content to fixed carbon content can be calculated by the following formula:

[0066]

[0067] where R af is the ratio of ash content to fixed carbon content, dimensionless; V f is the volume percentage of fixed carbon, %; V a is the volume percentage of ash, %.

[0068] The fracture pressure gradient of the coal seam can be calculated by the following formula:

[0069]

[0070] where G pf is the fracture pressure gradient of the coal seam, MPa / m; α is Biot's coefficient, dimensionless; P p is the formation pore pressure, MPa; Depth is the depth of the calculation point, m; μ is the Poisson's ratio of the coal seam, dimensionless; σ v is the vertical in-situ stress, MPa.

[0071] Continue to refer to Figure 1 , in step 130, according to the coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index, calculate the fracturing potential evaluation index corresponding to the coalbed methane reservoir.

[0072] In this application, after calculating the coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index, the fracturing potential evaluation index for comprehensively evaluating the fracturing potential of the coalbed methane reservoir can be calculated. According to the fracturing potential evaluation index, the coal seams in the coalbed methane reservoir can be screened, so as to select the coal seams with higher development potential and lower development difficulty for development.

[0073] Furthermore, the fracturing potential evaluation index can be calculated by the following formula:

[0074] I pf = I R × I C

[0075] where I pf is the fracturing potential evaluation index, dimensionless; I R is the coalbed methane reservoir quality index, dimensionless; I C is the coalbed methane reservoir engineering quality index, dimensionless.

[0076] In one embodiment of the present application, after calculating the fracturing potential evaluation index, based on the fracturing potential evaluation index, the fracturing potential of the coalbed methane reservoir is evaluated, specifically including step 131:

[0077] Step 131, if the fracturing potential evaluation index is greater than the first threshold, it is determined that the coalbed methane reservoir is an easily transformable reservoir, and the coalbed methane reservoir forms a network of fracturing cracks after fracturing, and the coalbed methane reservoir is a high-yield reservoir.

[0078] In this embodiment, referring to Table 1, it is a classification table of coalbed methane reservoir grades based on the fracturing potential evaluation index. In Table 1, the first threshold may be 52. If the product of the calculated coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index, that is, the value of the fracturing potential evaluation index, is greater than 52, it can be determined that the coalbed methane reservoir is an easily transformable reservoir, and the coalbed methane reservoir forms a network of fracturing cracks after fracturing, and the coalbed methane reservoir is a high-yield reservoir.

[0079]

[0080] Table 1

[0081] For example, referring to Figure 2 , it is a graph showing the evaluation results of the fracturing transformation potential of the coalbed methane reservoir according to the embodiment of the present application. In the coalbed methane reservoir section from 2479.25m to 2492.13m, the coal seam can be divided into upper and lower parts with a total thickness of 9m. There are obvious parting and sandy mudstone between the two small layers.

[0082] In the well section from 2479.25m to 2484.75m in the upper part of the coalbed methane reservoir, according to the logging data corresponding to the coalbed methane reservoir, the corresponding logging curves can be obtained, and the logging curves show good coal quality. The natural gamma curve value is between 28.0 and 55.0 API, the density curve value is between 1.31 and 1.48 g / cm 3 between, the well diameter shows slight enlargement, and the calculated average ash content is about 17.5%. The ash content is low. The gas saturation S of the coal seam in this well section g is between 76% and 89%, the total porosity φ of the coal seam c is between 4.3 and 5.2%, the permeability K of the coal seam c is between 0.19 and 0.54×10 -3 μm 2 between, and the effective thickness H of the coal seam ce is 5m. Therefore, the calculated coalbed methane reservoir quality index I R is between 1.96 and 2.22, with an average of 2.09, indicating that the coalbed methane reservoir has good quality.

[0083] Then, according to the logging data corresponding to the coalbed methane reservoir, the coal body structure index I in the well section can be obtained. cs is between 0.24 and 0.93, the coal seam stress index I σ is between 2.32 and 8.9, the brittleness index R af is between 35% and 67%, and the fracture pressure gradient G pf is between 1.83 and 2.14 MPa / 100m. Therefore, the calculated engineering quality index I of the coalbed methane reservoir c is between 26.7 and 33.4, with an average of 31.45, indicating that the engineering quality of the coalbed methane reservoir is good.

[0084] Combining the coalbed methane reservoir quality index and the coalbed methane reservoir engineering index, determine the fracturing potential evaluation index I corresponding to the well section pf is between 52.33 and 74.15, with an average of 65.73. According to the above-mentioned coalbed methane reservoir grading table based on the fracturing potential evaluation index, the fracturing potential evaluation grade of the reservoir corresponding to the well section is Class I. It can be determined that the coalbed methane reservoir is an easily transformable reservoir, and the coalbed methane reservoir forms a network of fracture cracks after fracturing, and the coalbed methane reservoir is a high-yield reservoir.

[0085] In another embodiment of the present application, after calculating the fracturing potential evaluation index, based on the fracturing potential evaluation index, evaluate the fracturing potential of the coalbed methane reservoir. Specifically, it may further include step 132:

[0086] Step 132, if the fracturing potential evaluation index is greater than the second threshold and less than the first threshold, determine that the coalbed methane reservoir is a medium-transformable reservoir, and the coalbed methane reservoir forms partial fracture cracks after fracturing, and the coalbed methane reservoir is a low-yield reservoir.

[0087] In this embodiment, continue to refer to Table 1. In Table 1, the first threshold may be 52, and the second threshold may be 39. If the product of the calculated coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index, that is, the value of the fracturing potential evaluation index, is greater than 28 and less than 52, it can be determined that the coalbed methane reservoir is a medium-transformable reservoir, and the coalbed methane reservoir forms partial fracture cracks after fracturing, and the coalbed methane reservoir is a low-yield reservoir.

[0088] For example, continue to refer to Figure 2 , in the coalbed methane reservoir section from 2479.25 m to 2492.13 m, the coal seam can be divided into upper and lower parts with a total thickness of 9 m. There are obvious parting and sandy mudstone between the two small layers.

[0089] In the well section from 2484.75m to 2486.3m in the upper part of the coalbed methane reservoir, according to the logging data corresponding to the coalbed methane reservoir, the corresponding logging curves can be obtained, and the logging curves show good coal quality. The natural gamma curve value is between 35.0 and 60.0 API, the density curve value is between 1.36 and 1.51 g / cm 3 3, the borehole diameter shows hole enlargement, and the calculated average ash content is about 22.4%, with a relatively high ash content. The gas saturation S g of the coal seam in this well section is between 57% and 75%, the total porosity φ c of the coal seam is between 3.7% and 4.5%, and the coal seam permeability K c is between 0.15 and 0.49×10 -3 μm 2 2. The effective thickness H ce of the coal seam is 4m. Therefore, the calculated coalbed methane reservoir quality index I R is between 1.80 and 1.88, with an average of 1.83, indicating that the quality of the coalbed methane reservoir is medium.

[0090] Then, according to the logging data corresponding to the coalbed methane reservoir, it can be known that the coal body structure index I cs in this well section is between 0.16 and 0.71, the coal seam stress index I σ is between 6.26 and 13.19, the brittleness index R af is between 28% and 55%, and the fracture pressure gradient G pf is between 1.95 and 2.31 MPa / 100m. Therefore, the calculated coalbed methane reservoir engineering quality index I c is between 22.5 and 24.8, with an average of 23.15, indicating that the engineering quality of the coalbed methane reservoir is medium.

[0091] Combining the coalbed methane reservoir quality index and the coalbed methane reservoir engineering index, the fracturing potential evaluation index I pf corresponding to this well section is determined to be between 40.5 and 46.62, with an average of 42.36. According to the above-mentioned coalbed methane reservoir grade division table based on the fracturing potential evaluation index, the fracturing potential evaluation grade of the reservoir corresponding to this well section is Class II. It can be determined that the coalbed methane reservoir is a medium-reformation reservoir, and after fracturing, some fracture cracks are formed in the coalbed methane reservoir, and the coalbed methane reservoir is a low-yield reservoir.

[0092] In another embodiment of the present application, after calculating the fracturing potential evaluation index, based on the fracturing potential evaluation index, the fracturing potential of the coalbed methane reservoir is evaluated. Specifically, it may further include step 133:

[0093] Step 133, if the fracturing potential evaluation index is less than the second threshold, it is determined that the coalbed methane reservoir is a difficult-to-transform reservoir, and no effective fracture can be formed in the coalbed methane reservoir, and the production of the coalbed methane reservoir is lower than the minimum industrial production.

[0094] In this embodiment, continue to refer to Table 1. In Table 1, the second threshold is 39. If the product of the calculated coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index, that is, the value of the fracturing potential evaluation index, is less than 38, it can be determined that the coalbed methane reservoir is a difficult-to-transform reservoir, and no effective fracture can be formed in the coalbed methane reservoir, and the production of the coalbed methane reservoir is lower than the minimum industrial production.

[0095] It should be noted that due to the strong differences in the geological characteristics of each coalbed methane reservoir, the grading standards for the evaluation of the fracturing potential of the reservoir vary greatly, and the grading standards need to be corrected before use. Since coal is brittle and easy to break, the influence of hole enlargement is inevitable, and both the acoustic time difference and compensated density logging in the well logging data corresponding to the coalbed methane reservoir will be affected by environmental factors such as hole enlargement. The accuracy of parameters such as the gas saturation of the coal seam, coal seam thickness, total porosity of the coal seam, coal seam permeability, coal body structure index, ratio of ash to fixed carbon content, fracture pressure gradient, and coal seam stress index calculated directly using well logging data is difficult to guarantee. In order to ensure the accuracy of the evaluation of the fracturing potential of the coalbed methane reservoir and the feasibility of the method, it is very necessary to correct the environmental influences such as hole enlargement on the well logging data of the coalbed methane reservoir.

[0096] The following introduces the device embodiments of the present application, which can be used to execute the method for determining the fracturing potential evaluation index in the above embodiments of the present application. For the details not disclosed in the device embodiments of the present application, please refer to the embodiments of the method for determining the fracturing potential evaluation index in the above of the present application.

[0097] Figure 3 It is a block diagram of a device for determining a fracturing potential evaluation index according to an embodiment of the present application.

[0098] Refer to Figure 3As shown, a fracturing potential evaluation index determination device 300 according to an embodiment of the present application, the device 300 includes: a first calculation unit 301, configured to calculate a coalbed methane reservoir quality index, the coalbed methane reservoir quality index being calculated through the gas saturation of the coal seam corresponding to the coalbed methane reservoir, the coal seam thickness, the coal seam permeability, and the total porosity of the coal seam; a second calculation unit 302, configured to calculate a coalbed methane reservoir engineering quality index, the coalbed methane reservoir engineering quality index being calculated through the coal body structure index, the coal seam stress index, the ratio of ash content to fixed carbon content, and the fracture pressure gradient corresponding to the coalbed methane reservoir; a third calculation unit 303, configured to calculate a fracturing potential evaluation index corresponding to the coalbed methane reservoir according to the coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index.

[0099] As another aspect, the present application also provides a computer-readable storage medium, on which a program product capable of implementing the above method of this specification is stored. In some possible implementation manners, various aspects of the present application can also be implemented in the form of a program product, which includes program code. When the program product runs on a terminal device, the program code is used to cause the terminal device to execute the steps according to various exemplary embodiments of the present application described in the above "Exemplary Method" section of this specification.

[0100] A computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, in which readable program code is carried. Such a propagated data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. The readable signal medium can also be any readable medium other than the readable storage medium, and this readable medium can send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device.

[0101] The program code included on the readable medium can be transmitted by any appropriate medium, including but not limited to wireless, wired, optical cable, RF, etc., or any suitable combination of the above.

[0102] The program code for performing the operations of this application can be written in any combination of one or more programming languages, including object-oriented programming languages such as Java, C++, etc., and also including conventional procedural programming languages such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computing device, partially on the user's device, executed as a stand-alone software package, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving a remote computing device, the remote computing device can be connected to the user's computing device through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computing device (e.g., by connecting through the Internet using an Internet service provider).

[0103] As another aspect, this application also provides an electronic device capable of implementing the above method.

[0104] Those skilled in the art can understand that various aspects of this application can be implemented as a system, method, or program product. Therefore, various aspects of this application can be specifically implemented in the following forms, namely: a complete hardware implementation, a complete software implementation (including firmware, microcode, etc.), or an implementation combining hardware and software aspects, which can be collectively referred to here as "circuitry", "module", or "system".

[0105] Figure 4 For a schematic diagram of the system structure of the electronic device shown according to the embodiments of this application, refer to the following Figure 4 to describe the electronic device 400 according to this embodiment of this application. Figure 4 The electronic device 400 shown is merely an example and should not impose any limitations on the functions and usage scope of the embodiments of this application.

[0106] As Figure 4 shown, the electronic device 400 is presented in the form of a general-purpose computing device. The components of the electronic device 400 may include, but are not limited to: at least one of the above-mentioned processing units 410, at least one of the above-mentioned storage units 420, and a bus 430 connecting different system components (including the storage unit 420 and the processing unit 410).

[0107] Among them, the storage unit stores program code, and the program code can be executed by the processing unit 410, so that the processing unit 410 executes the steps according to various exemplary embodiments of this application described in the "Embodiment Method" section of this specification.

[0108] The storage unit 420 may include a readable medium in the form of a volatile storage unit, such as a random access storage unit (RAM) 421 and / or a cache storage unit 422, and may further include a read-only storage unit (ROM) 423.

[0109] The storage unit 420 may also include a program / utilities 424 having a set (at least one) of program modules 425. Such program modules 425 include, but are not limited to: an operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment.

[0110] The bus 430 may represent one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processing unit, or a local bus using any of a variety of bus structures.

[0111] The electronic device 400 may also communicate with one or more external devices 1200 (such as a keyboard, a pointing device, a Bluetooth device, etc.), may also communicate with one or more devices that enable a user to interact with the electronic device 400, and / or may communicate with any device that enables the electronic device 400 to communicate with one or more other computing devices (such as a router, a modem, etc.). Such communication may be through an input / output (I / O) interface 450. Moreover, the electronic device 400 may also communicate with one or more networks (such as a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) through a network adapter 460. As shown in the figure, the network adapter 460 communicates with other modules of the electronic device 400 through the bus 430. It should be understood that, although not shown in the figure, other hardware and / or software modules may be used in conjunction with the electronic device 400, including but not limited to: microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems, etc.

[0112] Through the description of the above embodiments, those skilled in the art can easily understand that the example embodiments described herein can be implemented by software, or can be implemented by a combination of software and necessary hardware. Therefore, the technical solutions according to the embodiments of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, including several instructions to enable a computing device (which can be a personal computer, a server, a terminal device, or a network device, etc.) to execute the method according to the embodiments of the present application.

[0113] In addition, the above-mentioned drawings are only schematic illustrations of the processes included in the method according to the exemplary embodiments of the present application, rather than for restrictive purposes. It is easy to understand that the processes shown in the above-mentioned drawings do not indicate or limit the chronological order of these processes. Additionally, it is also easy to understand that these processes can be executed, for example, synchronously or asynchronously in multiple modules.

[0114] It should be understood that the present application is not limited to the exact structures that have been described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A method for determining a fracturing potential evaluation index, characterized in that, The method includes: Calculating a coalbed methane reservoir quality index, which is calculated from the coalbed methane saturation, coal seam thickness, coal seam permeability, and total porosity of the coalbed methane reservoir corresponding to the coalbed methane reservoir; Calculating a coalbed methane reservoir engineering quality index, which is calculated from the coal body structure index, coal seam stress index, ratio of ash content to fixed carbon content, and fracture pressure gradient corresponding to the coalbed methane reservoir; Calculating a fracturing potential evaluation index corresponding to the coalbed methane reservoir according to the coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index.

2. The method according to claim 1, characterized in that, After calculating the fracturing potential evaluation index, evaluating the fracturing potential of the coalbed methane reservoir based on the fracturing potential evaluation index, including: If the fracturing potential evaluation index is greater than a first threshold, determining that the coalbed methane reservoir is an easily transformable reservoir, and that the coalbed methane reservoir forms a network of fracturing cracks after fracturing, and that the coalbed methane reservoir is a high-yield reservoir.

3. The method according to claim 1, characterized in that, After calculating the fracturing potential evaluation index, evaluating the fracturing potential of the coalbed methane reservoir based on the fracturing potential evaluation index, including: If the fracturing potential evaluation index is greater than a second threshold and less than the first threshold, determining that the coalbed methane reservoir is a moderately transformable reservoir, and that the coalbed methane reservoir forms some fracturing cracks after fracturing, and that the coalbed methane reservoir is a low-yield reservoir.

4. The method according to claim 1, characterized in that, After calculating the fracturing potential evaluation index, evaluating the fracturing potential of the coalbed methane reservoir based on the fracturing potential evaluation index, including: If the fracturing potential evaluation index is less than the second threshold, determining that the coalbed methane reservoir is a difficult-to-transform reservoir, and that the coalbed methane reservoir cannot form effective fracturing cracks, and that the production of the coalbed methane reservoir is lower than the minimum industrial production.

5. The method according to claim 1, characterized in that, The coalbed methane reservoir quality index is calculated by the following formula, including: Among them, I R is the coalbed methane reservoir quality index, dimensionless; S g is the gas saturation of the coal seam, %; H c is the coal seam thickness, m; K c is the coal seam permeability, 10 -3 μm 2 ; is the total porosity of the coal seam, %.

6. The method according to claim 1, characterized in that, The coalbed methane reservoir engineering quality index is calculated by the following formula, including: Among them, I C is the engineering quality index of coalbed methane reservoir, dimensionless; I cs is the coal structure index, dimensionless; I σ is the coal seam stress index, dimensionless; R af is the ratio of ash content to fixed carbon content, dimensionless; G pf is the fracture pressure gradient of the coal seam, MPa / m.

7. The method according to claim 1, characterized in that, The fracturing potential evaluation index is calculated by the following formula, including: I pf = I R × I C Among them, I pf is the fracturing potential evaluation index, dimensionless; I R is the coalbed methane reservoir quality index, dimensionless; I C is the coalbed methane reservoir engineering quality index, dimensionless.

8. A device for determining a fracturing potential evaluation index, characterized in that, The device includes: A first calculation unit for calculating a coalbed methane reservoir quality index, which is calculated from the coalbed methane saturation, coal seam thickness, coal seam permeability, and total porosity of the coalbed methane reservoir corresponding to the coalbed methane reservoir; A second calculation unit for calculating a coalbed methane reservoir engineering quality index, which is calculated from the coal body structure index, coal seam stress index, ratio of ash content to fixed carbon content, and fracture pressure gradient corresponding to the coalbed methane reservoir; A third calculation unit for calculating a fracturing potential evaluation index corresponding to the coalbed methane reservoir according to the coalbed methane reservoir quality index and the coalbed methane reservoir engineering quality index.

9. A computer-readable storage medium, characterized in that, At least one program code is stored in the computer-readable storage medium, and the at least one program code is loaded and executed by a processor to implement the operations performed by the method according to any one of claims 1 to 7.

10. An electronic device, characterized in that, The electronic device includes one or more processors and one or more memories, and at least one program code is stored in the one or more memories. The at least one program code is loaded and executed by the one or more processors to implement the operations performed by the method according to any one of claims 1 to 7.

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