Reservoir pore pressure measurement method, measurement system, storage medium, and electronic device

Abstract

This invention discloses a method, system, electronic device, and storage medium for measuring reservoir pore pressure. The method includes establishing a model of the geostress magnitude in the Taihe gas-bearing area of ​​central Sichuan to obtain the maximum and minimum horizontal geostress; obtaining the geostress mechanism of the Taihe gas-bearing area based on the maximum and minimum horizontal geostress values; establishing a pore pressure calculation model for any depth point in the reservoir based on the geostress distribution law of the geostress mechanism to obtain the predicted pore pressure value at any depth point; comparing the predicted pore pressure value at any depth point with drilling data to obtain the comparison result; and revising the pore pressure calculation model for any depth point in the reservoir based on the comparison result to obtain a general pore pressure calculation model for the Taihe gas-bearing area. This method provides more accurate results. The measurement process is simple and the measurement time is shortened.

Description

Technical Field

[0001] This invention relates to the field of oil and gas exploration and development technology, specifically to a method, system, storage medium, and electronic device for measuring reservoir pore pressure. Background Technology

[0002] The Lower Paleozoic-Sinian carbonate gas reservoirs in central Sichuan were predicted to have reserves exceeding 200 billion cubic meters in 2020, demonstrating enormous development potential and making them an important future gas-producing reservoir in the Sichuan Basin. Based on the theory of reservoir formation in the Lower Paleozoic-Sinian system in central Sichuan, geological engineers have systematically conducted sequence stratigraphic studies, discovering new characteristics in the distribution patterns of geological reservoirs such as the Cambrian system. Influenced by multiple tectonic movements across multiple strata, the paleogeomorphological differences among the strata are significant, especially in the Taihe gas-bearing area located in the northern part of the eastern segment of the central Sichuan Paleo-Uplift.

[0003] The lithology of the Taihe gas-bearing area is mainly carbonate and clastic rocks. To accurately describe its rock mechanical properties and predict pressure variation trends under different lithological conditions, a comprehensive three-pressure prediction model for gas reservoirs is considered, utilizing well logging data. This model involves measuring the pore pressure in both carbonate and clastic rocks. However, existing pore pressure prediction methods typically require core samples taken at a certain depth under conventional pressure. These core samples undergo physical, chemical, and rock mechanical analyses through various tests. Based on the analysis results, a suitable pore pressure prediction calculation method for each reservoir depth is derived and selected. Then, the pore pressure of each reservoir is predicted using this selected method. Because this method does not predict pore pressure during drilling, its accuracy is low. Furthermore, this method requires multiple core samples taken at a certain depth from each well for analysis, followed by selection of a suitable pore pressure prediction calculation method based on the analysis results. This process is not only complex but also time-consuming, typically requiring more than six months or even several years to complete. Summary of the Invention

[0004] The technical problem this invention aims to solve is the low prediction accuracy of existing reservoir pore pressure prediction methods. The objective is to provide a reservoir pore pressure measurement method, measurement system, storage medium, and electronic device to address this problem.

[0005] The first objective of this invention is to provide a method for measuring reservoir pore pressure, comprising:

[0006] A model of geostress magnitude was established in the Taihe gas-bearing area of ​​central Sichuan to obtain the maximum and minimum horizontal geostress.

[0007] The geostress mechanism of the Taihe gas-bearing area was obtained based on the maximum and minimum horizontal geostress values.

[0008] Based on the stress distribution law of the aforementioned geostress mechanism, a method for constructing a pore pressure calculation model was selected. A pore pressure calculation model for any depth point in the Taihe gas-bearing reservoir was established, and the predicted pore pressure value at any depth point was obtained.

[0009] The comparison results are obtained by comparing the predicted pore pressure values ​​at any depth point in the reservoir with the drilling data.

[0010] Based on the comparison results, the pore pressure calculation model at any depth point in the reservoir was revised to obtain a general pore pressure calculation model for the Taihe gas-bearing area.

[0011] In this invention, by establishing a pore pressure calculation model for any depth point in the Taihe gas-bearing reservoir, the predicted pore pressure value at any depth point is obtained. Then, the predicted pore pressure value at any depth point in the reservoir is compared with the drilling data, and the pore pressure calculation model at any depth point is corrected based on the comparison results, which can greatly improve the accuracy of pore pressure measurement.

[0012] Furthermore, since the pore pressure calculation model is established at any depth, compared to the existing model which requires first analyzing core samples from a certain depth in the reservoir and then constructing a pore pressure calculation model based on a certain depth rather than an arbitrary depth, the calculation model constructed by this invention is more in line with the actual situation. It also incorporates real-time feedback and timely correction of the above model based on actual oil drilling data, making the corresponding reservoir pore pressure calculation and measurement method more scientific and effective, and the measurement results more accurate.

[0013] Meanwhile, the method of this invention does not require core sampling and analysis of each well during the development process, nor does it require selecting a suitable calculation method based on the core analysis results before calculating and measuring pore pressure. It can directly use the obtained general pore pressure calculation model for calculation and measurement, which eliminates the process of core sampling and analysis and selection of calculation methods, greatly simplifies the measurement process and saves measurement time.

[0014] Optionally, based on the lithological variation patterns of the Taihe gas-bearing area, as well as the interpretation of well logging data and data from adjacent wells, a model of the magnitude of geostress in the Taihe gas-bearing area can be established.

[0015] The lithological variation pattern is obtained by acquiring formation parameter information through well logging analysis, and then obtaining the lithological variation trend and mechanical parameter variation trend at different well depths in different regions based on the formation parameter information;

[0016] In the aforementioned geostress magnitude model for the Taihe gas-bearing area, the maximum and minimum horizontal geostress magnitude models are as follows:

[0017]

[0018]

[0019] Where, σH σ h These represent the maximum and minimum horizontal ground stresses, respectively; P op ξ1 and ξ2 are the original formation pressure; α is the Biot coefficient; ξ1 and ξ2 are the stress tectonic coefficients of the rock in the directions of maximum and minimum horizontal stress, respectively; P p denoted as pore pressure in the formation; E is the elastic modulus of the rock sample; μ is Poisson's ratio.

[0020] Optionally, ξ1 and ξ2 are constants in the same stratigraphic block, with ξ1 taking the value of 0.847 and ξ2 taking the value of 0.576.

[0021] Optionally, the calculation method for the rock sample's elastic modulus E and Poisson's ratio μ is as follows:

[0022]

[0023]

[0024] Where ΔP is the load increment; H is the specimen height; A is the specimen area; ΔH is the axial deformation increment; d L H represents the circumferential deformation. 轴向 denoted as axial deformation; D is the diameter of the specimen.

[0025] Optionally, the process of establishing a pore pressure calculation model at any depth point in the Taihe gas-bearing reservoir includes: constructing a normal compaction trend line based on the geostress distribution law and obtaining the equivalent depth.

[0026] Existing methods for determining reservoir pore pressure require core samples from multiple wells at certain depths for analysis of each well to be developed. This process is complex and time-consuming, typically taking more than six months or even several years to complete. To address these issues, this invention, in establishing the geostress magnitude model and the pore pressure calculation model at arbitrary depths in the Taihe gas area, only requires core sampling and analysis of the first well in a specific section to obtain data from adjacent wells. Based on this data and other data, the pore pressure calculation model at arbitrary depths can be gradually constructed, eliminating the need for further core sampling and analysis of subsequent wells in the same section. This simplifies the measurement method and saves measurement time.

[0027] Optionally, the equation for the normal compaction trend line is:

[0028] ln(Δt) = 4.895 - 4.1 × 10 -4 H T ;

[0029] The calculation model for pore pressure at any depth is as follows:

[0030] P p =G O ·(HT -H TA )+G N ·H TA ;

[0031] Where Δt is the measured time difference of the sound wave at the observation point; H T H represents the vertical depth of the measuring point. TA P represents the equivalent depth value of the measuring point. p G represents the formation pore pressure; Go represents the pressure gradient of the overlying strata; G N This represents the hydrostatic pressure gradient.

[0032] Optionally, the comparison result is obtained by comparing the predicted pore pressure at any depth point in the reservoir with the drilling data to obtain the factors affecting the actual values ​​of the measurement parameters and the direction of the normal compaction trend line.

[0033] The pore pressure calculation model at any depth point in the reservoir is modified based on the aforementioned influencing factors.

[0034] Optionally, the influencing factors include overlying formation pressure.

[0035] Optionally, by utilizing the effective stress principle and adding additional corrections, the pore pressure calculation model at any depth point in the reservoir is modified, resulting in the general pore pressure calculation model for the Taihe gas-bearing area:

[0036]

[0037] Among them, P pall The corrected pore pressure in the gas-bearing region of Taihe; ΔC p For additional correction; σ ν The overlying formation pressure is σ. ν The calculation method for the pore pressure acting on the reservoir is as follows:

[0038]

[0039] Among them, P N Δt is the hydrostatic pressure of the formation water column. N The acoustic transit time value is located on the normal compaction trend line at the same depth as the observation point. C The compaction index is 0.5.

[0040] A second objective of this invention is to provide a reservoir pore pressure measurement system, comprising:

[0041] The geostress magnitude model building module is used to build a geostress magnitude model for the Taihe gas-bearing area in central Sichuan.

[0042] The geostress mechanism determination module is used to determine the geostress mechanism based on the maximum and minimum horizontal geostress, and then obtain the geostress distribution law;

[0043] The trend line creation module is used to create normal compaction trend lines based on the distribution of ground stress.

[0044] The equivalent depth calculation module is used to calculate the equivalent depth value of the measuring point based on the distribution law of ground stress.

[0045] The prediction module is used to establish a pore pressure calculation model at any depth point based on the normal compaction trend line and the equivalent depth of the measuring point, so as to obtain the predicted value of the pore pressure at any depth point.

[0046] The comparison module is used to compare the predicted pore pressure values ​​at any depth point in the reservoir with the drilling data, and to obtain the values ​​of influencing factors.

[0047] The correction module is used to correct the pore pressure calculation model at any depth point in the reservoir based on the influencing factor values ​​obtained from the comparison results, thus creating a general pore pressure calculation model for the Taihe gas-bearing area.

[0048] A third object of the present invention is to provide an electronic device comprising at least one processor and a memory communicatively connected to the processor;

[0049] The memory stores a program that can be executed by the at least one processor, which enables the at least one processor to perform the above-described method for measuring reservoir pore pressure.

[0050] A fourth objective of this invention is to provide a computer-readable storage medium storing a computer program that is executed by a processor to implement the above-described method for measuring reservoir pore pressure.

[0051] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0052] This invention provides a novel method for determining reservoir pore pressure. By establishing a pore pressure calculation model for any depth point in the Taihe gas-bearing reservoir, predicted pore pressure values ​​at any depth point are obtained. These predicted values ​​are then compared with drilling data, and the calculation model is promptly revised based on the comparison results. This optimizes the calculation model, making the corresponding reservoir pore pressure calculation and determination method more scientific and effective, and the results more accurate. Furthermore, it eliminates the need for core sampling and analysis for every well, and avoids the need to select a suitable calculation method based on core analysis results before calculating and determining pore pressure. The obtained universal pore pressure calculation model can be used directly for calculation and determination, saving the processes of core sampling and analysis, and selection of calculation methods, greatly simplifying the measurement process and saving measurement time. Attached Figure Description

[0053] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0054] Figure 1 A flowchart of the measurement method provided in the embodiments of the present invention;

[0055] Figure 2 Schematic diagram of the measurement system provided in the embodiments of the present invention

[0056] Figure 3 This is a plan view of the tectonic units in the Sichuan Basin.

[0057] Figure 4 This is a predicted profile of reservoir pore pressure obtained using the measurement method of Example 1 of the present invention.

[0058] Figure 5 This is a comparison chart of the predicted pore pressure at any depth point obtained by the measurement method provided in Embodiment 1 of the present invention and the results of drilling data.

[0059] The labels in the figure represent: 11-Stress magnitude model establishment module, 12-Stress mechanism judgment module, 13-Trend line establishment module, 14-Equivalent depth calculation module, 15-Prediction module, 16-Comparison module, 17-Correction module. Detailed Implementation

[0060] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0061] In the following description, numerous specific details are set forth in order to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that these specific details are not necessary to practice the invention. In other embodiments, well-known structures, circuits, materials, or methods have not been specifically described in order to avoid obscuring the invention.

[0062] Throughout this specification, references to "an embodiment," "an example," or "an example" mean that a particular feature, structure, or characteristic described in connection with that embodiment or example is included in at least one embodiment of the present invention. Therefore, the phrases "an embodiment," "an example," "an example," or "an example" appearing in various places throughout the specification do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, or characteristics can be combined in one or more embodiments or examples in any suitable combination and / or sub-combination. Moreover, those skilled in the art will understand that the illustrations provided herein are for illustrative purposes and are not necessarily drawn to scale. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0063] In the description of this invention, the terms "front", "rear", "left", "right", "up", "down", "vertical", "horizontal", "high", "low", "inner", and "outer" 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 limiting the scope of protection of this invention.

[0064] Example 1:

[0065] like Figure 1 As shown, the technical solution of this embodiment is as follows: A model of the geostress magnitude of the Taihe gas-bearing zone is constructed based on well logging data interpretation and formation lithology analysis. Then, a corresponding reservoir pore pressure calculation model is derived. The predicted pore pressure values ​​are compared with oil drilling data during drilling to correct the model, thereby obtaining a more scientific method for calculating and determining reservoir pore pressure. Specifically, the following operational steps are included:

[0066] S1. Obtain the geological overview and relevant parameters of the Taihe gas-bearing area, and conduct well logging analysis on the local downhole conditions to understand the lithological variation patterns of the Taihe gas-bearing area; the specific process is as follows:

[0067] like Figure 3 As shown, the Taihe gas-bearing area belongs to the gently sloping tectonic zone of the central Sichuan uplift in the Sichuan Basin. It has undergone several sedimentary evolution and tectonic movements in the Sichuan Basin, successively depositing marine carbonate strata of the Middle and Lower Triassic and terrestrial sandstone and mudstone strata of the Upper Triassic to Jurassic. The main geological movement is differential uplift and subsidence, resulting in a relatively weak overall tectonic structure and a gentle surface. Using well logging methods, an evaluation method for shear wave, density, and neutron logging data was constructed. Specifically, 12 wells were logged for 5 layers using shear wave logging, and 10 wells were logged for density and neutron logging.

[0068] Taking a well in the Taihe gas-bearing area as an example, a density of 1.96 g / cm³ was used. 3The well was drilled using a combination of organic salt polysulfonate drilling fluid. At a depth of 2436m, the formation consisted of gray fine sandstone, which was prone to lost circulation. Formation parameters were obtained through analysis using the aforementioned logging methods. Taking a well in the Taihe gas-bearing area as an example, the logging results estimated that the average reservoir porosity was 4.08%, and the permeability distribution range was large, with an average value of 1.02 mD, indicating that this formation is a low-porosity, low-permeability reservoir.

[0069] Based on the obtained formation parameter information, the lithological variation patterns in the Taihe gas-bearing area can be determined. These patterns include the trends in strata variation and mechanical parameter variation at different depths and in different regions. Specific methods for obtaining this information can utilize existing technologies, which will not be detailed here.

[0070] S2. Based on the lithological variation patterns of the Taihe gas-bearing area, well logging interpretation, and adjacent well data, a model of the magnitude of geostress in the Taihe gas-bearing area is established; the specific process is as follows:

[0071] A geostress magnitude model was established using lithological variation patterns, well logging interpretation, and data from adjacent wells, with the adjacent well data already obtained in advance. The formulas for calculating the rock elastic modulus and Poisson's ratio involved are as follows:

[0072]

[0073]

[0074] In the formula: E is the elastic modulus of the rock sample, in MPa; μ is Poisson's ratio, dimensionless; ΔP is the load increment, in MPa; H is the sample height, in m; A is the sample area, in m². 2 ; ΔH is the axial deformation increment; d L H represents the circumferential deformation, measured in meters (m). 轴向 This represents the axial deformation, expressed in meters (m).

[0075] For the upper strata of the Taihe well area, this stratum is defined as a homogeneous isotropic linear elastic body. It is assumed that no relative displacement occurs between the strata during the later stages of geological tectonic movement, and that the strain in both horizontal directions of all strata is constant. Therefore, the calculation model for the magnitude of geostress in the Taihe gas area is as follows:

[0076]

[0077] Where: σ H σ h These represent the maximum and minimum horizontal ground stresses, respectively, in MPa; P op The original formation pressure (obtainable from geological data) is expressed in MPa; α is the Biot coefficient; P in formula (1) pξ1 and ξ2 are the stress tectonic coefficients of the rock in the directions of maximum and minimum horizontal stress, respectively. In the same stratigraphic block, ξ1 and ξ2 are constants and can be taken as 0.847 and 0.576, respectively.

[0078] S3. Based on the distribution law of geostress, select the method to construct the pore pressure calculation model, establish the pore pressure calculation model at any depth point of the Taihe gas-bearing reservoir, and obtain the predicted value of pore pressure at any depth point.

[0079] The maximum and minimum horizontal geostress values ​​were calculated using the calculation model for the maximum and minimum horizontal geostress in step S2. Considering the lithological characteristics of carbonate and clastic rocks in the Taihe gas region, and based on the maximum and minimum horizontal geostress values ​​and by consulting relevant literature, it is readily known that the maximum horizontal principal stress is greater than the overlying stratum pressure σ. ν The minimum horizontal principal stress is used to deduce that the stress mechanism in the Taihe gas-bearing area is a strike-slip fault stress mechanism. Based on this stress mechanism, the stress distribution pattern can be determined. The specific process of determining this pattern can be carried out using existing technologies, which will not be elaborated here. Based on this stress mechanism, a method for constructing a pore pressure calculation model at arbitrary depth points is selected. In this embodiment, the approach to calculating pore pressure is to construct a normal compaction trend line and obtain the equivalent depth. The normal compaction trend line is obtained through regression calculation and empirical adjustment of well logging readings from the argillaceous layer in the normal pressure well section.

[0080] The equation for the normal compaction trend line is as follows:

[0081] ln(Δt) = 4.895 - 4.1 × 10 -4 H T

[0082] Based on data including the normal compaction trend line and the equivalent depth of measuring points, the following model is established for calculating pore pressure at arbitrary depth points:

[0083] P p =G O ·(H T -H TA )+G N ·H TA Formula (2)

[0084] In the formula: Δt is the measured time difference of the sound wave at the observation point, in μs / ft; H T H represents the vertical depth of the measuring point, in meters (m). TA The equivalent depth value of the measuring point is in meters; P in formula (2) p G represents the corrected formation pore pressure; Go represents the pressure gradient of the overlying strata, in MPa / 100m; N This represents the hydrostatic pressure gradient, expressed in MPa / 100m.

[0085] Simultaneously, based on the pore pressure calculation model at any depth point in the reservoir, a predicted pore pressure profile for the corresponding reservoir can be generated. As an example, the predicted pore pressure profile for the corresponding reservoir can be seen... Figure 4 .

[0086] S4. Using oil drilling data while drilling, compare the predicted pore pressure values ​​at any depth point in the reservoir with the data while drilling to correct the model; the specific process is as follows:

[0087] By comparing the predicted pore pressure values ​​at any depth point in the reservoir with drilling data, the factors affecting the actual values ​​of the measured parameters and the direction of the normal compaction trend line were obtained. The comparison results are as follows: Figure 5 As shown. According to Figure 5 It can be seen that changes in overlying strata pressure affect the actual values ​​of measured parameters and the direction of the normal compaction trend line; that is, the influencing factor is overlying strata pressure. The formula for calculating the effect of overlying strata pressure on pore pressure is:

[0088]

[0089] In the formula: σ ν P represents the overlying formation pressure, in MPa; N Δt represents the hydrostatic pressure of the formation water column in MPa; N The sonic transit time, expressed in µs / ft, is the time difference of sound waves along the normal compaction trend line at the same depth as the observation point. C This is the formation compaction index.

[0090] To obtain a more accurate normal compaction trend line, the effective stress principle is used to add an additional correction amount ΔC. p Meanwhile, by setting the compaction index to 0.5 and modifying the pore pressure calculation model at any depth, a general pore pressure calculation model for the Taihe gas region is obtained:

[0091]

[0092] In the formula: P pall The corrected pore pressure in the Taihe gas region is expressed in MPa; ΔC p This is an additional correction amount.

[0093] In this embodiment, the approach to reservoir pore pressure measurement is as follows: First, the predicted pore pressure value at any depth point in the reservoir is obtained using the above method. Then, it is compared with the data obtained during drilling. Based on the comparison results, the pore pressure calculation model at any depth point is corrected, thereby optimizing the calculation model. This correction significantly improves the prediction accuracy and further enhances the accuracy of the drilling measurement data. Furthermore, compared with existing methods, core samples are only required when acquiring data from adjacent wells in a specific section. Core analysis is no longer necessary for subsequent well development, greatly saving the time spent on reservoir pore pressure measurement during drilling, reducing the time to 2-3 months and significantly decreasing project operation time.

[0094] Example 2:

[0095] A reservoir pore pressure measurement system, based on the measurement method of Example 1, such as... Figure 2 As shown, it includes:

[0096] Module 11 for establishing a geostress magnitude model is used to establish a geostress magnitude model for the Taihe gas-bearing area in central Sichuan.

[0097] The geostress mechanism judgment module 12 is used to judge the geostress mechanism based on the maximum and minimum horizontal geostress, and then obtain the geostress distribution law;

[0098] Trend line establishment module 13 is used to establish normal compaction trend lines based on the distribution law of ground stress.

[0099] Equivalent depth calculation module 14 is used to calculate the equivalent depth value of the measuring point based on the distribution law of ground stress;

[0100] Prediction module 15 is used to establish a pore pressure calculation model at any depth point based on the normal compaction trend line and the equivalent depth of the measuring point, so as to obtain the predicted value of pore pressure at any depth point.

[0101] The comparison module 16 is used to compare the predicted pore pressure at any depth point in the reservoir with the drilling data, and to obtain the actual values ​​of the measurement parameters and the values ​​of the factors affecting the direction of the normal compaction trend line based on the comparison results.

[0102] The correction module 17 is used to correct the pore pressure calculation model at any depth of the reservoir based on the influencing factor values ​​obtained from the comparison results, and to obtain the general pore pressure calculation model for the Taihe gas-bearing area.

[0103] Among them, the geostress magnitude model establishment module 11 is connected to the geostress mechanism judgment module 12, the geostress mechanism judgment module 12 is connected to the trend line establishment module 13 and the equivalent depth calculation module 14, the trend line establishment module 13 and the equivalent depth calculation module 14 are both connected to the prediction module 15, the prediction module 15 is connected to the comparison module 16, and the comparison module 16 is connected to the correction module 17.

[0104] Example 3:

[0105] This embodiment provides a computer-readable storage medium storing a computer program, which is executed by a processor to implement a reservoir pore pressure measurement method as described in Embodiment 1.

[0106] Example 4:

[0107] This embodiment provides an electronic device, which includes at least one processor and a memory communicatively connected to the processor; the memory stores a program executable by the at least one processor, which is executed by the at least one processor to enable the at least one processor to perform a reservoir pore pressure measurement method as described in Embodiment 1.

[0108] In addition, all processes and methods not involved in the embodiments of the present invention are based on existing technologies and will not be described in detail here.

[0109] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for measuring reservoir pore pressure, characterized in that, include: A model of geostress magnitude was established in the Taihe gas-bearing area of ​​central Sichuan to obtain the maximum and minimum horizontal geostress. The geostress mechanism of the Taihe gas-bearing area was obtained based on the maximum and minimum horizontal geostress values. Based on the stress distribution law of the aforementioned geostress mechanism, a method for constructing a pore pressure calculation model was selected. A pore pressure calculation model for any depth point in the Taihe gas-bearing reservoir was established, and the predicted pore pressure value at any depth point was obtained. The comparison results are obtained by comparing the predicted pore pressure values ​​at any depth point in the reservoir with the drilling data. Based on the comparison results, the pore pressure calculation model at any depth point in the reservoir was revised to obtain the general pore pressure calculation model for the Taihe gas-bearing area. The process of establishing a pore pressure calculation model for reservoirs at arbitrary depths in the Taihe gas-bearing area includes: constructing a normal compaction trend line based on the geostress distribution law and obtaining the equivalent depth; The equation for the normal compaction trend line is: ； The calculation model for pore pressure at any depth is as follows: ； in, The measured time difference of sound waves at the observation point; The vertical depth of the measuring point; This represents the equivalent depth value of the measuring point. ρ represents the formation pore pressure; ρ represents the pressure gradient of the overlying strata. For hydrostatic pressure gradient; The comparison results are obtained by comparing the predicted pore pressure at any depth point in the reservoir with the drilling data to identify the factors that affect the actual values ​​of the measurement parameters and the direction of the normal compaction trend line. The calculation model for pore pressure at any depth point in the reservoir is modified based on the aforementioned influencing factors. The influencing factors include overlying formation pressure; By utilizing the effective stress principle and adding additional corrections, a modified pore pressure calculation model at any depth in the reservoir is obtained, resulting in a general pore pressure calculation model for the Taihe gas-bearing area: ； in, The corrected pore pressure in the gas-bearing zone of Taihe. Additional correction amount; This refers to the pressure of the overlying strata. Overlying formation pressure The calculation method for the pore pressure acting on the reservoir is as follows: ； in, This refers to the hydrostatic pressure of the formation water column. The acoustic transit time value is located on the normal compaction trend line at the same depth as the observation point. The compaction index is 0.

5.

2. The method for determining reservoir pore pressure as described in claim 1, characterized in that, Based on the lithological variation patterns of the Taihe gas-bearing area, as well as the interpretation of well logging data and data from adjacent wells, a model of the magnitude of geostress in the Taihe gas-bearing area was established. The lithological variation pattern is obtained by acquiring formation parameter information through well logging analysis, and then obtaining the lithological variation trend and mechanical parameter variation trend at different well depths in different regions based on the formation parameter information; In the aforementioned geostress magnitude model for the Taihe gas-bearing area, the maximum and minimum horizontal geostress magnitude models are as follows: ； in, These represent the maximum and minimum horizontal ground stresses, respectively. α represents the original formation pressure; α is the Biot coefficient. These are the stress tectonic coefficients of the rock in the directions of maximum and minimum horizontal stress, respectively; Pp is the formation pore pressure. The elastic modulus of the rock sample; It is Poisson's ratio.

3. The method for determining reservoir pore pressure as described in claim 2, characterized in that, The Within the same stratigraphic block, all faults are constants. The value is 0.

847. The value is 0.

576.

4. The method for determining reservoir pore pressure as described in claim 3, characterized in that, The rock sample's elastic modulus E and Poisson's ratio The calculation method is as follows: ； in, For load increments; The height of the sample; The area of ​​the sample; This represents the axial deformation increment; This refers to the circumferential deformation. This refers to the axial deformation. The diameter is the sample diameter.

5. A reservoir pore pressure measurement system, characterized in that, include: The geostress magnitude model building module is used to build a geostress magnitude model for the Taihe gas-bearing area in central Sichuan. The geostress mechanism determination module is used to determine the geostress mechanism based on the maximum and minimum horizontal geostress, and then obtain the geostress distribution law; The trend line creation module is used to create normal compaction trend lines based on the distribution of ground stress. The equivalent depth calculation module is used to calculate the equivalent depth value of the measuring point based on the distribution law of ground stress. The prediction module is used to establish a pore pressure calculation model at any depth point based on the normal compaction trend line and the equivalent depth of the measuring point, so as to obtain the predicted value of the pore pressure at any depth point. The comparison module is used to compare the predicted pore pressure values ​​at any depth point in the reservoir with the drilling data, and to obtain the values ​​of influencing factors. The correction module is used to correct the pore pressure calculation model at any depth point in the reservoir based on the influencing factor values ​​obtained from the comparison results, thus creating a general pore pressure calculation model for the Taihe gas-bearing area. The process of establishing a pore pressure calculation model at arbitrary depth points includes: constructing a normal compaction trend line based on the geostress distribution law and determining the equivalent depth; The equation for the normal compaction trend line is: ； The calculation model for pore pressure at any depth is as follows: ； in, The measured time difference of sound waves at the observation point; The vertical depth of the measuring point; P represents the equivalent depth value of the measuring point. p G represents the formation pore pressure; Go represents the pressure gradient of the overlying strata. For hydrostatic pressure gradient; The comparison results are obtained by comparing the predicted pore pressure at any depth point in the reservoir with the drilling data to identify the factors that affect the actual values ​​of the measurement parameters and the direction of the normal compaction trend line. The calculation model for pore pressure at any depth point in the reservoir is modified based on the aforementioned influencing factors. The influencing factors include overlying formation pressure; By utilizing the effective stress principle and adding additional corrections, a modified pore pressure calculation model at any depth in the reservoir is obtained, resulting in a general pore pressure calculation model for the Taihe gas-bearing area: ； in, The corrected pore pressure in the gas-bearing zone of Taihe. Additional correction amount; This refers to the pressure of the overlying strata. Overlying formation pressure The calculation method for the pore pressure acting on the reservoir is as follows: ； in, This refers to the hydrostatic pressure of the formation water column. The acoustic transit time value is located on the normal compaction trend line at the same depth as the observation point. The compaction index is 0.

5.

6. A computer-readable storage medium storing a computer program, characterized in that, The computer program is executed by a processor to implement a reservoir pore pressure measurement method as described in any one of claims 1 to 4.

7. An electronic device, characterized in that, The electronic device includes at least one processor and a memory communicatively connected to the processor; The memory stores a program that can be executed by the at least one processor, the program being executed by the at least one processor to enable the at least one processor to perform a reservoir pore pressure measurement method as described in any one of claims 1 to 4.

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