Tight gas reservoir rock compressibility evaluation method and system, computer equipment and medium

Abstract

The invention discloses a tight gas reservoir rock compressibility evaluation method and system, computer equipment and a medium, and relates to the technical field of petroleum and natural gas development. The method comprises the following steps: testing to obtain rock sample parameters of a target reservoir rock sample; on the basis of the rock sample parameters of the target reservoir rock sample, the rock natural fracture crushing degree is obtained through calculation; based on the rock sample parameters of the target reservoir rock sample, obtaining the potential of reservoir transformation to form a fracture network; and according to the natural fracture crushing degree of the rock and the potential of forming a fracture network through reservoir transformation, calculating to obtain a rock compressibility index which is used for evaluating the rock compressibility. The rock compressibility is dynamically evaluated by comprehensively considering the natural fracture crushing degree and whether the potential of forming a complex fracture network through reservoir transformation can obtain high productivity or not, and technical support is provided for tight oil and gas exploration and development.

Description

Technical Field

[0001] This application relates to the field of oil and gas development technology, specifically to a method, system, computer equipment, and medium for evaluating the compressibility of rocks in tight gas reservoirs. Background Technology

[0002] Rock compressibility is a key factor influencing the formation of complex fracture networks through volumetric fracturing, and a core indicator for oil and gas resource exploration and reservoir quality evaluation. Tight gas reservoirs in my country are highly heterogeneous, with uneven distribution of sand bodies in both vertical and horizontal directions, and extremely complex distribution and development of natural fractures. These factors, particularly the initial fragmentation of natural fractures, are core influences on rock compressibility. Furthermore, compressibility is a crucial basis for reservoir stimulation segment selection and fracturing parameter optimization, directly impacting the achievement of high single-well productivity and oil production rates.

[0003] The current research on rock compressibility evaluation mainly falls into the following categories: (1) Starting from the influence of mineral brittleness and natural fractures, based on the principle that the better the mineral brittleness, the greater the influence factor of natural fractures, and the better the rock compressibility, the mineral compressibility is optimized by using the number of fractures from the triaxial rock mechanics test. Then, combined with the natural fracture characteristics of the reservoir, the rock compressibility characteristics are described, and the weight coefficients of the influence factors of mineral compressibility and natural fractures are calculated to evaluate the rock compressibility. (2) Determine the mineral composition deviation coefficient based on the shale mineral composition; determine the dynamic Young's modulus and dynamic Poisson's ratio of various minerals; based on the dynamic Young's modulus and dynamic Poisson's ratio of various minerals, use the composition model to determine the estimated Young's modulus and estimated Poisson's ratio of the reservoir. Through linear fitting, obtain the corresponding fitted Young's modulus and fitted Poisson's ratio linear fitting formulas calculated from the dynamic Young's modulus and dynamic Poisson's ratio, and calculate the brittleness coefficient. (3) The types and contents of mineral components in shale samples were measured by indoor experiments, the phase difference between different minerals was calculated and the differences between minerals were evaluated, and a shale brittleness evaluation model based on the heterogeneity of mineral components was established to evaluate the compressibility potential of shale.

[0004] The three methods mentioned above all evaluate rock compressibility based on mineral composition or mechanical properties, without considering the dynamic evaluation of rock compressibility from the perspective of whether the potential for high productivity can be achieved through the formation of complex fracture networks by later volumetric fracturing. Furthermore, none of them take into account the highly developed natural fractures in unconventional reservoirs, which play a dominant role in assessing rock compressibility during reservoir stimulation. Therefore, there is an urgent need to establish a quantitative and qualitative evaluation method for rock compressibility that conforms to actual unconventional tight gas reservoirs, providing a fundamental theoretical basis for evaluating the oil and gas resource potential and volumetric fracturing effectiveness of similar reservoirs. Summary of the Invention

[0005] To address the issue that existing rock compressibility evaluation technologies do not consider the effects of subsequent volumetric fracturing, this application proposes a method, system, computer equipment, and medium for evaluating the compressibility of tight gas reservoirs. This application dynamically evaluates rock compressibility by comprehensively considering the degree of natural fracture fragmentation and the potential of reservoir stimulation to form a complex fracture network to achieve high production capacity, providing technical support for tight oil and gas exploration and development.

[0006] This application is achieved through the following technical solution:

[0007] A method for evaluating the compressibility of rocks in tight gas reservoirs, the method comprising:

[0008] The rock sample parameters of the target reservoir rock sample were obtained through testing; wherein the target reservoir rock sample was prepared by sampling.

[0009] Based on the rock sample parameters of the target reservoir rock sample, the degree of natural fracture in the rock is calculated;

[0010] Based on the rock sample parameters of the target reservoir, the potential for reservoir stimulation to form a fracture network is obtained;

[0011] Based on the degree of natural fractures in the rock and the potential for reservoir stimulation to form a fracture network, a rock compressibility index is calculated and used for rock compressibility evaluation.

[0012] In some implementations, the test obtains rock sample parameters of the target reservoir rock sample, specifically including:

[0013] Obtain the percentage of each mineral content in the target reservoir rock sample;

[0014] The Young's modulus of the target reservoir rock sample was obtained.

[0015] In some embodiments, the calculation of the natural fracture degree of the rock based on the rock sample parameters of the target reservoir rock sample specifically includes:

[0016] Based on the rock sample parameters of the target reservoir, the single-mineral fracture fragmentation degree is calculated using the following formula:

[0017]

[0018] In the formula, M dj The fracture degree of a single mineral; n is the number of minerals; E dj This refers to the Young's modulus of a single mineral;

[0019] Based on the single-mineral fracture fragmentation, the natural fracture fragmentation of the rock is calculated using the following formula:

[0020]

[0021] In the formula, M p The degree of fracturing of natural cracks in the rock.

[0022] In some implementations, the method of obtaining the reservoir stimulation potential to form a fracture network based on the rock sample parameters of the target reservoir specifically includes:

[0023] Based on the rock sample parameters of the target reservoir, the new proportion of minerals other than the highest percentage of brittle minerals is calculated using the following formula:

[0024]

[0025] In the formula, k wi The new percentage of minerals excluding the highest percentage of brittle minerals; k wmax The highest percentage of brittle minerals;

[0026] The calculated proportion of new minerals is combined with the degree of mineral alteration to obtain the overall mineral fracture network formation degree. The calculation formula is as follows:

[0027]

[0028] In the formula, G Z The overall mesh formation degree.

[0029] In some implementations, the compressibility index is calculated using the following formula:

[0030] B = M p G z ×10 -4

[0031] In the formula, B is the rock compressibility index; M p G represents the average fracture degree of the rock sample; Z The overall mesh formation degree.

[0032] In some embodiments, the method further includes:

[0033] According to the rock compressibility classification standard, the corresponding evaluation results are obtained and output based on the compressibility index.

[0034] Secondly, this application proposes a system for evaluating the compressibility of rocks in tight gas reservoirs, the system comprising:

[0035] The testing module obtains the rock sample parameters of the target reservoir rock sample through testing; wherein the target reservoir rock sample is prepared by sampling.

[0036] The first calculation module calculates the degree of natural fracture in the rock based on the rock sample parameters of the target reservoir rock sample.

[0037] The second calculation module, based on the rock sample parameters of the target reservoir rock sample, obtains the potential for reservoir stimulation to form a fracture network;

[0038] And a third calculation module, which calculates the rock compressibility index based on the natural fracture degree of the rock and the potential for reservoir stimulation to form a fracture network, for use in rock compressibility evaluation.

[0039] In some embodiments, the first computing module further includes:

[0040] A single mineral unit is used, and the single mineral fracture degree is calculated based on the rock sample parameters of the target reservoir rock sample. The calculation formula is as follows:

[0041]

[0042] In the formula, M dj The fracture degree of a single mineral; n is the number of minerals; E dj This refers to the Young's modulus of a single mineral;

[0043] And, a rock sample unit, wherein the rock sample unit calculates the natural fracture degree of the rock based on the single mineral fracture degree, and the calculation formula is:

[0044]

[0045] In the formula, M p The degree of fracturing of natural cracks in the rock.

[0046] In some embodiments, the second computing module further includes:

[0047] The proportioning unit calculates the new mineral proportions, excluding the highest percentage of brittle minerals, based on the rock sample parameters of the target reservoir sample. The calculation formula is as follows:

[0048]

[0049] In the formula, k wi The new percentage of minerals excluding the highest percentage of brittle minerals; k wmax The highest percentage of brittle minerals;

[0050] And, a formation degree unit, which combines the calculated proportion of new minerals with the degree of mineral modification to obtain the overall mineral fracture network formation degree, calculated using the following formula:

[0051]

[0052] In the formula, G Z The overall mesh formation degree.

[0053] In some implementations, the third calculation module calculates the compressibility index using the following formula:

[0054] B = M p G z ×10 -4

[0055] In the formula, B is the rock compressibility index; M p G represents the average fracture degree of the rock sample; Z The overall mesh formation degree.

[0056] In some embodiments, the system further includes:

[0057] The output module obtains and outputs the corresponding evaluation results based on the compressibility index according to the rock compressibility level classification standard.

[0058] Thirdly, this application proposes a computer device including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the above-described method.

[0059] Fourthly, this application proposes a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described method.

[0060] This application discloses a method, system, computer equipment, and medium for evaluating the compressibility of rocks in tight gas reservoirs. First, target reservoir rock samples are obtained, and their mineral composition and rock mechanical parameters are tested. Then, based on the basic parameters of the rock samples, the fragmentation degree of individual fractures is evaluated. The average fragmentation degree of the entire rock sample is calculated to evaluate the fragmentation degree of natural fractures. Next, based on the degree of bonding between brittle minerals and individual minerals in the rock samples, the overall fracture network formation degree is calculated. Finally, combining the natural fracture fragmentation degree and the overall fracture network formation degree, a new rock compressibility index is defined to quantitatively evaluate the compressibility of tight reservoirs.

[0061] This application discloses a method, system, computer equipment, and medium for evaluating the compressibility of rocks in tight gas reservoirs. This method can quickly and accurately evaluate rock compressibility, greatly saving costs and improving efficiency. It is also applicable to the evaluation of rock compressibility in similar unconventional reservoirs, providing a technical basis for the efficient exploration and development of tight gas reservoirs. Attached Figure Description

[0062] The accompanying drawings, which are included to provide a further understanding of the embodiments of this application and form part of this application, do not constitute a limitation on the embodiments of this application. In the drawings:

[0063] Figure 1 This is a flowchart of the evaluation method according to an embodiment of this application;

[0064] Figure 2 This is a system principle block diagram of an embodiment of this application;

[0065] Figure 3 This is a comparison diagram of the overall fracture network formation degree of rock samples H1 to H3 in the embodiments of this application;

[0066] Figure 4 This is a comparison chart of the compressibility indices of rock samples H1 to H3 in the embodiments of this application. Detailed Implementation

[0067] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this application are only for explaining this application and are not intended to limit this application.

[0068] Example 1:

[0069] This embodiment proposes a method for evaluating the compressibility of rocks in tight gas reservoirs. The method first obtains target reservoir rock samples and tests the mineral composition and rock mechanical parameters of the samples. Then, based on the basic parameters of the rock samples, the fragmentation degree of individual fractures is evaluated, and the degree of fragmentation of natural fractures is evaluated by calculating the average fragmentation degree of the entire rock sample. Next, the overall fracture network formation degree is calculated based on the degree of bonding between brittle minerals and individual minerals in the rock samples. Finally, by combining the natural Lie-peak fragmentation degree and the overall fracture formation degree, a rock compressibility index is obtained to quantitatively evaluate the rock compressibility of tight reservoirs.

[0070] like Figure 1 As shown, the method proposed in this embodiment specifically includes the following steps:

[0071] Step 100: Obtain the rock sample parameters of the target reservoir rock sample. Specifically, use X-ray diffraction to obtain the percentage (k) of minerals in the target reservoir rock sample. wj (j = 1, ..., n), where n represents the number of minerals; the Young's modulus E of the rock sample was obtained using a triaxial rock mechanics testing system. m The target reservoir rock sample is obtained through sampling preparation. Specifically, according to the evaluation reservoir layer, downhole coring is carried out, and the obtained target reservoir rock sample is made into a standard rock sample with a diameter of 2.5 cm and a length of 5 cm. The rock sample is then placed in a 100°C oven and dried to constant weight.

[0072] Step 200: Based on the rock sample parameters of the target reservoir rock sample, calculate the degree of natural fracture in the rock.

[0073] This step 200 specifically includes the following processes:

[0074] Step 201: Calculate the fragmentation degree of individual mineral fractures based on rock sample parameters. The fragmentation degree of natural fractures distributed in the reservoir depends on the difference in mechanical properties between the minerals on both sides of the fracture formation. This difference in mechanical properties is expressed as the difference between a single mineral and the overall assemblage, and the calculation formula is as follows:

[0075]

[0076] In the formula, M dj The fracture degree of a single mineral is expressed in MPa; n is the number of minerals, dimensionless; E dj The value represents the Young's modulus of a single mineral, in MPa.

[0077] Step 202: Calculate the natural fracture degree of the rock based on the single-mineral fracture degree. Specifically, the natural fracture degree of the rock can be obtained by averaging the single-mineral fracture degree of the rock sample, using the following formula:

[0078]

[0079] In the formula, M p The value represents the natural fracture degree of the rock, expressed in MPa. A higher value indicates that the reservoir rock is more easily fractured.

[0080] Step 300: Based on the rock sample parameters of the target reservoir rock sample, the potential for reservoir stimulation to form a fracture network is obtained.

[0081] Step 300 specifically includes the following processes:

[0082] Step 301: Based on the rock sample parameters, calculate the new proportion of minerals excluding the highest percentage of brittle minerals. The formation of the fracture network mainly relies on the fracturing of brittle minerals within the rock sample. Therefore, in this embodiment, the highest percentage of brittle minerals measured in the rock sample is first selected as the standard. Then, the remaining minerals are evenly combined around the highest percentage of brittle minerals, and the proportion is recalculated. The calculation formula is as follows:

[0083]

[0084] In the formula, k wi The new percentage of minerals excluding the highest percentage of brittle minerals, %; k wmax The highest percentage of brittle minerals is represented by %.

[0085] Step 302: Combine the calculated proportion of new minerals with the degree of mineral alteration to obtain the overall mineral fracture network formation degree. The specific calculation formula is as follows:

[0086]

[0087] In the formula, G ZThe overall mesh formation degree is dimensionless. The higher the overall mesh formation degree, the greater the potential for mesh formation.

[0088] Step 400: Based on the degree of natural rock fractures and the potential for reservoir stimulation to form a fracture network, the rock compressibility index is calculated and used for rock compressibility evaluation.

[0089] Based on the initial natural fracture fragmentation of the rock and the potential for reservoir stimulation to form a fracture network, a compressibility index is defined to comprehensively evaluate rock compressibility. A higher compressibility index value indicates stronger rock compressibility and greater production capacity from reservoir stimulation. The formula for calculating the compressibility index is as follows:

[0090] B = M p G z ×10 -4 (5)

[0091] In the formula, B is the rock compressibility index, MPa; M p The average fracture fragmentation of the rock sample is expressed in MPa and G. Z The overall mesh formation degree is dimensionless.

[0092] This embodiment can divide the rock compressibility evaluation standard into four levels based on experience or historical data:

[0093] (1) When the compressibility index is between 0 and 0.25, the rock compressibility is poor;

[0094] (2) When the compressibility index is between 0.25 and 0.50, the rock compressibility is generally good;

[0095] (3) When the compressibility index is between 0.50 and 0.75, the rock has good compressibility;

[0096] (4) When the compressibility index is between 0.75 and 1.0, the rock has good compressibility.

[0097] Therefore, after obtaining the compressibility index, the method proposed in this embodiment can obtain and output the corresponding evaluation results according to the above-mentioned rock compressibility level classification standard.

[0098] The method proposed in this embodiment dynamically evaluates delayed compressibility by comprehensively considering the factors of natural fracture fragmentation and the potential for high productivity from reservoir stimulation to create complex fractures. It quantitatively characterizes parameters such as natural Li peak fragmentation and rock compressibility. Furthermore, the method proposed in this embodiment is simple and effective, significantly reducing costs and improving efficiency. It is also applicable to the evaluation of rock compressibility in similar unconventional reservoirs, providing a technical basis for the efficient exploration and development of tight gas reservoirs.

[0099] Based on the same technical concept described above, this embodiment also proposes a system for evaluating the compressibility of tight gas reservoir rocks, such as... Figure 2 As shown, the system proposed in this embodiment specifically includes:

[0100] The testing module obtains the rock sample parameters of the target reservoir rock sample through testing. The specific implementation process of this module is as described in step 100 above, and will not be repeated here. The target reservoir rock sample is prepared through sampling, specifically as follows: based on the evaluated reservoir layer, downhole coring is carried out, and the obtained target reservoir rock sample is made into a standard rock sample with a diameter of 2.5 cm and a length of 5 cm. The rock sample is then dried in a 100℃ oven until constant weight.

[0101] The first calculation module calculates the degree of natural fracture in the rock based on the rock sample parameters of the target reservoir rock sample.

[0102] The second calculation module, based on the rock sample parameters of the target reservoir, obtains the potential for reservoir stimulation to form a fracture network.

[0103] Furthermore, the third calculation module calculates the rock compressibility index based on the degree of natural rock fracture and the reservoir's potential for fracturing to form a fracture network, which is used for rock compressibility evaluation. The specific implementation process of this module is as described in step 400 above, and will not be elaborated further here.

[0104] Furthermore, the system proposed in this embodiment also includes:

[0105] The output module outputs the corresponding rock compressibility evaluation results based on the rock compressibility index according to the preset rock compressibility level classification standard.

[0106] Furthermore, the first computing module also includes:

[0107] The single-mineral unit calculates the fracture degree of the single mineral based on the rock sample parameters. The specific calculation method is as described in step 201, and will not be repeated here.

[0108] In addition, there is a rock sample unit, which calculates the natural fracture degree of the rock based on the fracture degree of a single mineral fracture. The specific calculation method is as described in step 202, and will not be elaborated further here.

[0109] Furthermore, the second computing module also includes:

[0110] The percentage calculation unit calculates the new percentage of minerals other than the highest percentage of brittle minerals based on the rock sample parameters. The specific calculation method is as described in step 301, and will not be repeated here.

[0111] In addition, there is a formation degree unit, which combines the calculated proportion of new minerals with the degree of mineral alteration to obtain the overall mineral fracture network formation degree. The specific calculation formula is as described in step 302, and will not be elaborated further here.

[0112] 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.

[0113] 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, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0114] 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.

[0115] 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.

[0116] Example 2:

[0117] This embodiment verifies the feasibility of the evaluation method proposed in the above embodiments. The specific process is as follows:

[0118] (1) Rock sample collection and processing: Three rock samples were taken from the tight gas reservoir where the horizontal well QH-1 is located and processed into standard rock samples with a diameter of 2.5 cm and a length of 5 cm. The rock samples were numbered H1, H2 and H3 and placed in a 100℃ oven to dry to constant weight.

[0119] (2) Obtaining rock sample parameters: The percentage of mineral content k was calculated using an X-ray diffractometer. wj The Young's modulus E of the rock sample was obtained using a triaxial rock mechanics testing system. m Five minerals were selected for testing, so the value of n is 5. The basic parameters are shown in Table 1.

[0120] Table 1. Mineralogical and mechanical parameters of rock samples obtained.

[0121]

[0122] (3) Evaluation of the fragmentation degree of natural cracks: using the formula The fracture fragmentation degree of each single mineral was calculated, and the average fracture fragmentation degree of the rock sample was calculated using Equation (2). According to the Young's modulus of the single minerals obtained from the "Handbook of Rock Physics", the Young's modulus of dolomite was 105309.01 MPa, quartz was 95942.54 MPa, calcite was 78010.81 MPa, feldspar was 64838.72 MPa, and clay minerals were 21914.15 MPa. The Young's modulus of the single minerals was ranked according to their magnitude. The Young's modulus of dolomite was E d5 Quartz is E d4 Calcite is E d3 Feldspar is E d2 The clay mineral is E d1 The data is shown in Table 2.

[0123] Table 2 Rock and Mineral Fracture Degree

[0124]

[0125] (4) Evaluation of the potential for complex fracture network formation: First, the brittle minerals with the highest proportion in the rock samples were selected. Rock sample H1 was dolomite, rock sample H2 was quartz, and rock sample H3 was calcite. The mineral proportions were recalculated using equation (3). Then, the overall fracture network formation degree was calculated using equation (4). The calculation results are shown in Table 3 and Figure 3 As shown.

[0126] Table 3. Calculation results of overall fracture network formation degree of rock samples.

[0127]

[0128] Rock compressibility evaluation: Based on the initial natural fracture fragmentation of the rock and the potential for reservoir stimulation to form a fracture network, the compressibility indices of rock samples H1 to H3 were calculated using equation (5) to be 0.303, 0.546, and 0.180, respectively, as shown in Table 4 and... Figure 4 As shown in the figure. According to the rock compressibility classification standard, the compressibility of the reservoir rock in rock sample H1 is generally good, the compressibility of the reservoir rock in rock sample H2 is relatively good, and the compressibility of the reservoir rock in rock sample H3 is relatively poor. Obtaining the percentage of fluid production contribution after reservoir stimulation for the three rock samples in the mine can indirectly reflect the reservoir compressibility. The higher the percentage of fluid production contribution, the better the rock compressibility, thus verifying the applicability and accuracy of the method of this application. The fluid production contribution percentage of the reservoir rock sample H1 is 10.5%, that of the reservoir rock sample H2 is 12.5%, and that of the reservoir rock sample H3 is 6.7%, which have a good correlation with the calculation in this example, verifying the accuracy of the invention of this application.

[0129] Table 4. Results of Rock Sample Compressibility Calculation

[0130]

[0131] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this application. It should be understood that the above description is only a specific embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for evaluating the compressibility of rocks in tight gas reservoirs, characterized in that, The method includes: The rock sample parameters of the target reservoir rock sample were obtained through testing; wherein the target reservoir rock sample was prepared by sampling. Based on the rock sample parameters of the target reservoir rock sample, the degree of natural fracture in the rock is calculated; Based on the rock sample parameters of the target reservoir, the potential for reservoir stimulation to form a fracture network is obtained; Based on the degree of natural fractures in the rock and the potential for reservoir stimulation to form a fracture network, a rock compressibility index is calculated and used for rock compressibility evaluation.

2. The method for evaluating the compressibility of tight gas reservoir rocks according to claim 1, characterized in that, The test obtained the rock sample parameters of the target reservoir rock sample, specifically including: Obtain the percentage of each mineral content in the target reservoir rock sample; The Young's modulus of the target reservoir rock sample was obtained.

3. The method for evaluating the compressibility of tight gas reservoir rocks according to claim 2, characterized in that, The calculation of the natural fracture degree of the rock based on the rock sample parameters of the target reservoir specifically includes: Based on the rock sample parameters of the target reservoir, the single-mineral fracture fragmentation degree is calculated using the following formula: In the formula, M dj The fracture degree of a single mineral; n is the number of minerals; E dj This refers to the Young's modulus of a single mineral; Based on the single-mineral fracture fragmentation, the natural fracture fragmentation of the rock is calculated using the following formula: In the formula, M p The degree of fracturing of natural cracks in the rock.

4. The method for evaluating the compressibility of tight gas reservoir rocks according to claim 2, characterized in that, The method of obtaining the reservoir stimulation potential to form a fracture network based on the rock sample parameters of the target reservoir specifically includes: Based on the rock sample parameters of the target reservoir, the new proportion of minerals other than the highest percentage of brittle minerals is calculated using the following formula: In the formula, k wi The new percentage of minerals excluding the highest percentage of brittle minerals; k wmax The highest percentage of brittle minerals; The calculated proportion of new minerals is combined with the degree of mineral alteration to obtain the overall mineral fracture network formation degree. The calculation formula is as follows: In the formula, G Z The overall mesh formation degree.

5. A method for evaluating the compressibility of tight gas reservoir rocks according to any one of claims 1-4, characterized in that, The formula for calculating the compressibility index is as follows: B=M p G z ×10 -4 In the formula, B is the rock compressibility index; M p G represents the average fracture degree of the rock sample; Z The overall mesh formation degree.

6. The method for evaluating the compressibility of tight gas reservoir rocks according to claim 5, characterized in that, The method further includes: According to the rock compressibility classification standard, the corresponding evaluation results are obtained and output based on the compressibility index.

7. A system for evaluating the compressibility of rocks in tight gas reservoirs, characterized in that, The system includes: The testing module obtains the rock sample parameters of the target reservoir rock sample through testing; wherein the target reservoir rock sample is prepared by sampling. The first calculation module calculates the degree of natural fracture in the rock based on the rock sample parameters of the target reservoir rock sample. The second calculation module, based on the rock sample parameters of the target reservoir rock sample, obtains the potential for reservoir stimulation to form a fracture network; And a third calculation module, which calculates the rock compressibility index based on the natural fracture degree of the rock and the potential for reservoir stimulation to form a fracture network, for use in rock compressibility evaluation.

8. The tight gas reservoir rock compressibility evaluation system according to claim 7, characterized in that, The first computing module further includes: A single mineral unit is used, and the single mineral fracture degree is calculated based on the rock sample parameters of the target reservoir rock sample. The calculation formula is as follows: In the formula, M dj The fracture degree of a single mineral; n is the number of minerals; E dj This refers to the Young's modulus of a single mineral; And, a rock sample unit, wherein the rock sample unit calculates the natural fracture degree of the rock based on the single mineral fracture degree, and the calculation formula is: In the formula, M p The degree of fracturing of natural cracks in the rock.

9. The tight gas reservoir rock compressibility evaluation system according to claim 7, characterized in that, The second calculation module further includes: The proportioning unit calculates the new mineral proportions, excluding the highest percentage of brittle minerals, based on the rock sample parameters of the target reservoir sample. The calculation formula is as follows: In the formula, k wi The new percentage of minerals excluding the highest percentage of brittle minerals; k wmax The highest percentage of brittle minerals; And, a formation degree unit, which combines the calculated proportion of new minerals with the degree of mineral modification to obtain the overall mineral fracture network formation degree, calculated using the following formula: In the formula, G Z The overall mesh formation degree.

10. The tight gas reservoir rock compressibility evaluation system according to claim 7, characterized in that, The third calculation module calculates the compressibility index using the following formula: B=M p G z ×10 -4 In the formula, B is the rock compressibility index; M p G represents the average fracture degree of the rock sample; Z The overall mesh formation degree.

11. A system for evaluating the compressibility of tight gas reservoir rocks according to any one of claims 7-10, characterized in that, The system also includes: The output module obtains and outputs the corresponding evaluation results based on the compressibility index according to the rock compressibility level classification standard.

12. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1-6.

13. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1-6.

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