Method and apparatus for pore pressure management in shale formations

Abstract

The pore pressure processing method and apparatus for shale formations provided in this application are applied to computer equipment. The method includes: receiving a user-uploaded acquisition command for a target shale formation through a preset interactive interface, and acquiring corresponding multi-source data and the duration of the geological process accordingly; determining the pore elastic parameters and sealing-decompression related parameters of the target shale formation based on the multi-source data; determining the corresponding hydraulic diffusion coefficient and sealing-decompression time scale based on the sealing-decompression related parameters; determining the corresponding decompression weight based on the sealing-decompression time scale and the duration of the geological process; constructing a temperature-pressure coupled control equation based on the multi-source data and pore elastic parameters; calculating the corresponding target pore pressure increment based on the decompression weight and the temperature-pressure coupled control equation; and determining the target pore pressure of the target shale formation based on the target pore pressure increment, thereby improving the accuracy and applicability of pore pressure processing for shale formations.

Description

Technical Field

[0001] This application relates to the fields of oil and gas exploration and development and geological engineering, and in particular to a method and apparatus for treating pore pressure in mudstone and shale formations. Background Technology

[0002] Shale and mudstone formations are widely developed in sedimentary basins and serve as important carriers for the enrichment and preservation of unconventional oil and gas. Formation pore pressure and its evolution directly affect the generation, migration, accumulation, and preservation conditions of shale oil and gas, and are also closely related to drilling safety, fracturing effectiveness, and reservoir sweet spot identification. Therefore, establishing pore pressure management methods suitable for shale and mudstone formations has significant scientific and engineering value.

[0003] In existing technologies, pore pressure assessment methods for shale formations mainly rely on the following four types of techniques: First, empirical inversion based on the normal compaction trend (NCT), using well logging data such as sonic transit time to establish a normal compaction trend line; second, basin simulation and numerical models, combining parameters such as geological history, thermal evolution, and fluid migration to simulate pressure evolution; third, single-mechanism models, such as hydrocarbon generation pressurization models, calculating pressure increments for specific mechanisms; and fourth, empirical formulas and end-member analysis, judging the degree of overpressure through pressure coefficient ratios. These techniques achieve formation pressure assessment through different approaches.

[0004] However, existing technologies have shortcomings in terms of unified coupling of multiple overpressure mechanisms, quantitative decomposition of overpressure contribution, time-scale constraints of decompression process, and uniformity of input data sources. For example, the mechanism coupling ability is poor, quantitative decomposition depends on empirical assumptions, parameters such as permeability and porosity are not explicitly correlated in the decompression process, and data sources are not uniform. Affected by these factors, existing technologies have technical problems such as low pore pressure processing accuracy and poor applicability in shale formations. Summary of the Invention

[0005] The pore pressure treatment method and apparatus for shale formations provided in this application are intended to improve the accuracy of pore pressure treatment in shale formations and enhance the applicability of the treatment.

[0006] In a first aspect, this application provides a method for processing pore pressure in shale formations, applied to computer equipment, the method comprising:

[0007] The system receives user-uploaded acquisition instructions for the target shale formation through a preset interactive interface, and obtains multi-source data and geological process duration of the target shale formation based on the acquisition instructions. The multi-source data includes at least one or more of the following types: well logging data, formation temperature or formation thermal history data, geochemical data, rock property data, fluid property data, formation burial history data, and measured or verified pressure data.

[0008] Based on multi-source data, the porosity elastic parameters and sealing-decompression related parameters of the target mudstone and shale formation were determined;

[0009] Based on the closure-depressurization related parameters, determine the corresponding hydraulic diffusion coefficient and closure-depressurization time scale;

[0010] The corresponding depressurization weights are determined based on the closure-depressurization timescale and the duration of the geological process;

[0011] Based on multi-source data and pore elastic parameters, a temperature-pressure coupled control equation is constructed. The temperature-pressure coupled control equation expresses the stress effect, temperature effect, and the effects of multiple mechanism source terms as a superposition term of pore pressure increment.

[0012] Calculate the corresponding target pore pressure increment based on the pressure relief weight and the temperature-pressure coupling control equation;

[0013] The target pore pressure of the target mudstone and shale formation is determined based on the target pore pressure increment.

[0014] Secondly, this application provides a pore pressure treatment device for shale formations, applied to computer equipment, the device comprising:

[0015] The acquisition module is used to receive acquisition instructions related to the target shale formation uploaded by the user through a preset interactive interface, and to acquire multi-source data and geological process duration of the target shale formation based on the acquisition instructions. The multi-source data includes at least one or more of the following types: well logging data, formation temperature or formation thermal history data, geochemical data, rock property data, fluid property data, and measured or verified pressure data.

[0016] The first processing module is used to determine the porosity elastic parameters and sealing-decompression related parameters of the target mudstone and shale formation based on multi-source data.

[0017] The second processing module is used to determine the corresponding hydraulic diffusion coefficient and the closure-decompression time scale based on the closure-decompression related parameters.

[0018] The third processing module is used to determine the corresponding depressurization weight based on the closure-depressurization timescale and the duration of the geological process;

[0019] The module is used to construct temperature-pressure coupled control equations based on multi-source data and pore elastic parameters. The temperature-pressure coupled control equations express the stress, temperature and multi-mechanism source terms as a superposition of pore pressure increments.

[0020] The calculation module is used to calculate the corresponding target pore pressure increment based on the pressure relief weight and the temperature-pressure coupling control equation;

[0021] The fourth processing module is used to determine the target pore pressure of the target mudstone and shale formation based on the target pore pressure increment.

[0022] Thirdly, this application provides a pore pressure treatment device for shale formations, comprising: a memory and a processor;

[0023] The memory stores the instructions that the computer executes;

[0024] The processor executes computer execution instructions stored in memory, causing the processor to perform the first aspect and / or various possible implementations of the first aspect as described above.

[0025] Fourthly, this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the first aspect and / or various possible embodiments of the first aspect.

[0026] Fifthly, this application provides a computer program product, including a computer program that, when executed by a processor, implements the first aspect and / or various possible implementations of the first aspect.

[0027] This application provides a method and apparatus for processing pore pressure in shale formations. It acquires multi-source data and geological process durations of the target shale formation by receiving user-uploaded instructions. The multi-source data covers various aspects, providing a rich foundation for subsequent processing and enhancing its applicability. It determines pore elasticity and sealing-relief related parameters, providing a basis for calculating hydraulic diffusion coefficients, etc. It determines the hydraulic diffusion coefficient and sealing-relief timescale, and then calculates the relief weight, making the processing more comprehensive. It constructs a temperature-pressure coupled control equation to unify multiple effects and improve processing accuracy. It calculates the target pore pressure increment and finally determines the target pore pressure. The entire process integrates multiple factors, thereby achieving the technical effect of improving the accuracy and enhancing the applicability of pore pressure processing in shale formations. Attached Figure Description

[0028] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0029] Figure 1 This application provides a schematic diagram of an application data processing system architecture.

[0030] Figure 2 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 1 ;

[0031] Figure 3 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 2 ;

[0032] Figure 4 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 3 ;

[0033] Figure 5 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 4 ;

[0034] Figure 6 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 5 ;

[0035] Figure 7 A diagram showing the calculation results of a decrease in formation pressure due to a decrease in formation temperature caused by structural uplift, as provided in an embodiment of this application;

[0036] Figure 8 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 6 ;

[0037] Figure 9 A diagram showing the calculation results of formation pressure state provided for an embodiment of this application;

[0038] Figure 10 A schematic diagram of the formation pressure evolution history provided for embodiments of this application;

[0039] Figure 11 A schematic diagram of the pore pressure treatment device for mudstone and shale formations provided in the embodiments of this application;

[0040] Figure 12 A schematic diagram of the pore pressure treatment device for mudstone and shale formations provided in this application embodiment.

[0041] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0042] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0043] Due to shortcomings in existing technologies regarding the unified coupling of multiple overpressure mechanisms, quantitative decomposition of overpressure contributions, time-scale constraints on the decompression process, and uniformity of input data sources, such as poor mechanism coupling ability, reliance on empirical assumptions for quantitative decomposition, lack of explicit correlation between parameters such as permeability and porosity during the decompression process, and inconsistent data sources, existing technologies suffer from low accuracy and poor applicability in pore pressure processing of shale formations.

[0044] To address the aforementioned issues, this application provides a method and apparatus for processing pore pressure in shale formations. This method acquires multi-source data and geological process durations of the target shale formation by receiving user-uploaded instructions. The multi-source data covers various aspects, providing a rich foundation for subsequent processing and enhancing its applicability. It determines pore elasticity and sealing-relief related parameters, providing a basis for calculating hydraulic diffusion coefficients, etc. It determines the hydraulic diffusion coefficient and sealing-relief timescale, thereby calculating the relief weight, making the processing more comprehensive. It constructs a temperature-pressure coupled control equation to unify multiple effects and improve processing accuracy. Finally, it calculates the target pore pressure increment and determines the target pore pressure. The entire process integrates multiple factors, thus achieving the technical effect of improving the accuracy and enhancing the applicability of pore pressure processing in shale formations.

[0045] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0046] Figure 1 This is a schematic diagram of an application data processing system architecture provided in an embodiment of this application. The application data processing system is a computer device. Figure 1 As shown, the above architecture includes at least one of a data acquisition device 101, a processing device 102, and a display device 103.

[0047] It is understood that the structures illustrated in the embodiments of this application do not constitute a specific limitation on the architecture of the application data processing system. In other feasible embodiments of this application, the above architecture may include more or fewer components than illustrated, or combine some components, or split some components, or arrange different components, which can be determined according to the actual application scenario and is not limited here. Figure 1 The components shown can be implemented in hardware, software, or a combination of both.

[0048] In the specific implementation process, the data acquisition device 101 may include an input / output interface or a communication interface, and the data acquisition device 101 can be connected to the processing device through the input / output interface or the communication interface.

[0049] The processing device 102 constructs a unified temperature-pressure coupled control equation, integrates multiple overpressure mechanisms such as negative compaction, hydrocarbon generation / cracking pressurization, tectonic uplift unloading, and thermal disturbance, and introduces a closure-decompression time scale constraint to achieve dynamic simulation of pore pressure in shale formations and quantitative decomposition of mechanism contributions. Specifically, it can first receive acquisition commands to obtain multi-source data and geological process duration of the target shale formation, and determine the pore elasticity and closure-decompression related parameters accordingly. Then, it calculates the hydraulic diffusion coefficient and the closure-decompression time scale to determine the decompression weight. At the same time, it constructs a temperature-pressure coupled control equation that uniformly expresses multiple effects. Finally, it calculates the target pore pressure increment and determines the target pore pressure by combining the decompression weight.

[0050] The display device 103 can also be a touch screen or the screen of a terminal device, used to receive user commands while displaying the above-mentioned content, so as to realize interaction with the user.

[0051] It should be understood that the aforementioned processing device can be implemented by a processor reading instructions from memory and executing those instructions, or it can be implemented by a chip circuit.

[0052] Furthermore, the network architecture and business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0053] Figure 2 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 1 ,like Figure 2 As shown, the pore pressure treatment method for shale formations provided in this embodiment is applied to computer equipment, and the method includes:

[0054] S201. Receive the user's uploaded acquisition command for the target shale formation through a preset interactive interface, and obtain multi-source data and geological process duration of the target shale formation according to the acquisition command.

[0055] In this embodiment, the multi-source data includes at least one or more of the following types: well logging data, formation temperature or formation thermal history data, geochemical data, rock property data, fluid property data, formation burial history data, and measured or verified pressure data.

[0056] For example, the computer equipment receives the user's uploaded target shale formation acquisition command through preset interactive interfaces such as data upload ports and visual interactive interfaces. The command must include requirements such as the burial depth range of the target stratum and the data acquisition accuracy. Based on the acquisition command, the equipment retrieves multi-source data of the target shale formation from end-side sources such as geological logging systems and basin simulation databases, while simultaneously acquiring the duration of the corresponding geological processes, and finally outputs a feedback signal indicating that the data acquisition is complete to the user's interactive terminal.

[0057] S202. Based on multi-source data, determine the porosity elastic parameters and sealing-decompression related parameters of the target mudstone and shale formation.

[0058] In this embodiment, the pore elastic parameters include the thermal expansion coefficient of the shale skeleton, the pore volume compressibility coefficient, the solid particle compressibility coefficient, the pore fluid equivalent thermal expansion coefficient, the pore fluid equivalent compressibility coefficient, the stress term coefficient, and the thermal term coefficient; the closure-decompression related parameters include rock permeability, porosity, fluid viscosity, total compressibility, and drainage characteristic length.

[0059] In one possible implementation, before determining the porosity parameters and sealing-decompression related parameters of the target shale formation based on multi-source data, the method further includes: performing depth registration, anomaly removal, stratification, and statistical processing on the multi-source data to obtain processed multi-source data.

[0060] For example, the multi-source data is first processed by depth coordinate calibration for depth registration, threshold screening for anomaly removal, stratified lithological interface division, and statistical characteristic value calculation, and a standardized unified multi-source dataset is output. Then, based on the processed data, the stress term coefficient and thermal term coefficient are calculated by combining the measured thermal expansion coefficient and pore volume compressibility coefficient of the shale skeleton with parameter fitting. Based on the seepage experiment and well logging curve inversion in the multi-source data, the sealing-decompression related parameters such as rock permeability and porosity are determined. All parameters are output as dimensional values ​​and vertical layer distribution curves.

[0061] S203. Based on the relevant parameters of closure-depressurization, determine the corresponding hydraulic diffusion coefficient and closure-depressurization time scale.

[0062] For example, the computer device substitutes the relevant parameters of closure-depression into the dedicated calculation model of hydraulic diffusion coefficient, obtains the specific value of hydraulic diffusion coefficient through numerical iteration, and then calculates the closure-depression time scale by combining the drainage characteristic length and using the scale conversion formula.

[0063] Optionally, this step can output the calculation results of the hydraulic diffusion coefficient and the closure-depressurization timescale, while generating an error analysis report of the parameter calculations.

[0064] S204. Determine the corresponding pressure relief weights based on the closure-depressurization timescale and the duration of the geological process.

[0065] In one possible implementation, the corresponding decompression weight is determined based on the closure-decompression timescale and the duration of the geological process, including: determining the decompression weight using a preset exponential function based on the closure-decompression timescale and the duration of the geological process.

[0066] In this embodiment, the pressure relief weight expression is as follows:

[0067]

[0068] Where w is the pressure relief weight and t is the duration of the geological process. This is the closure-decompression timescale.

[0069] For example, the computer equipment first performs a unified conversion of the time units for the closure-decompression timescale and the duration of the geological process, then substitutes them into a preset exponential function for calculation, and obtains the decompression weight through the function numerical solution.

[0070] Optionally, this step can output a single value of the depressurization weight or a weight change curve as a function of geological time, and simultaneously push the results to subsequent calculations.

[0071] S205. Based on multi-source data and pore elastic parameters, construct temperature-pressure coupled control equations.

[0072] In this embodiment, the temperature-pressure coupled control equation expresses the effects of stress, temperature, and multiple mechanistic sources as a superposition of pore pressure increments.

[0073] Based on the geological features of the strata extracted from multi-source data and combined with the determined pore elastic parameters, the computer equipment constructs a temperature-pressure coupled control equation under the physical constraints of small deformation and volume compatibility. This equation unifies the quantitative calculation of stress, temperature and multi-mechanism source terms into a superposition of pore pressure increments. Finally, it outputs the mathematical expression of the control equation, the parameter assignment table and the results of the equation's rationality verification.

[0074] S206. Calculate the corresponding target pore pressure increment based on the pressure relief weight and the temperature-pressure coupling control equation.

[0075] The computer equipment uses the pressure relief weight as the closure-pressure relief correction coefficient, substitutes it into the temperature-pressure coupled control equation, performs pressure relief correction on the increment of each action term in the temperature-pressure coupled control equation, and then calculates the contribution of each increment step by step according to the superposition principle, finally obtaining the target pore pressure increment.

[0076] Optionally, this step can output the target pore pressure increment value, the quantitative contribution value of each component increment, and generate a process data log for increment calculation.

[0077] S207. Determine the target pore pressure of the target mudstone and shale formation based on the target pore pressure increment.

[0078] The computer equipment superimposes the target pore pressure increment with the initial pore pressure of the formation determined by the actual pressure measurement or verification data, and performs spatial interpolation processing in combination with the formation stratification characteristics to finally determine the target pore pressure of the target mudstone and shale formation at different burial depths and geological times.

[0079] Optionally, this step can output two-dimensional / three-dimensional pore pressure field distribution maps, longitudinal profiles of pressure coefficients, and pore pressure evolution data tables to the user interface.

[0080] This application provides a method for processing pore pressure in shale formations. It acquires multi-source data and geological process durations of the target shale formation by receiving user-uploaded instructions. The multi-source data covers various aspects, providing a rich foundation for subsequent processing and enhancing its applicability. It determines pore elasticity and sealing-relief related parameters, providing a basis for calculating hydraulic diffusion coefficients, etc. It determines the hydraulic diffusion coefficient and sealing-relief timescale, and then calculates the relief weight, making the processing more comprehensive. It constructs a temperature-pressure coupled control equation to unify multiple effects and improve processing accuracy. It calculates the target pore pressure increment and finally determines the target pore pressure. The entire process integrates multiple factors, thereby achieving the technical effect of improving the accuracy and enhancing the applicability of pore pressure processing in shale formations.

[0081] Figure 3 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 2 ,like Figure 3 As shown, this embodiment, based on the above embodiments, provides a detailed explanation of the specific construction process of the temperature-pressure coupled control equation, including:

[0082] S301. Based on the multi-source data, determine the corresponding contribution of the multi-mechanism source terms, the average total stress increment, and the temperature change.

[0083] In this embodiment, the contribution of the multi-mechanism source term is the sum of the pore pressure increments corresponding to various overpressure mechanisms, and the average total stress increment is the equivalent unloading or loading stress increment.

[0084] Based on multi-source data of the target shale formation, the contribution of multiple mechanisms, the average total stress increment, and the temperature change were calculated and determined. The contribution of multiple mechanisms is the sum of the pore pressure increments corresponding to each overpressure mechanism such as negative compaction, hydrocarbon generation, and crude oil cracking. The average total stress increment is the stress increment generated during the equivalent unloading or loading process of the formation. The temperature change is calculated from geological processes such as formation uplift and burial or changes in geothermal flow.

[0085] Optionally, the negative compaction pressure contribution can be calculated by the burial rate, the hydrocarbon generation pressure contribution can be calculated based on the total organic carbon (TOC) and kerogen conversion rate, and the cracking pressure contribution can be calculated when the maturity reaches the oil cracking stage. The contribution of the three types of increments can be summed to obtain the contribution of the multi-mechanism source terms. The average total stress increment can be derived from the geostress calculation formula, and the temperature change can be calculated by combining the geothermal gradient and the formation uplift or the change of geothermal heat flow.

[0086] S302. Based on the contribution of multiple source terms, the average total stress increment, the temperature change and the pore elastic parameters, construct the temperature-pressure coupled control equation.

[0087] In this embodiment, the process expression of the temperature-pressure coupled control equation is as follows:

[0088]

[0089] in, , , B is the pore pressure increment, and B is the stress term coefficient. This represents the average total stress increment. The coefficient of thermal term, It is the product of the temperature changes. Contribution to multi-mechanism source terms; β p β is the pore volume compressibility coefficient. f β is the equivalent compressibility coefficient of the pore fluid. s Let α be the compressibility coefficient of the solid particles. f α is the equivalent thermal expansion coefficient of the pore fluid. s The coefficient of thermal expansion of the shale skeleton is given.

[0090] Based on the established contributions of multiple mechanistic source terms, average total stress increment, and temperature change, and combined with pore elastic parameters, a temperature-pressure coupled control equation is constructed according to a predetermined process expression. First, the stress term coefficient and thermal term coefficient are calculated using pore elastic parameters such as the pore volume compressibility coefficient. Then, each coefficient is multiplied by its corresponding increment, and the contributions of multiple mechanistic source terms are superimposed to obtain a complete expression for the pore pressure increment.

[0091] The pore pressure processing method for shale formations provided in this application provides accurate and comprehensive basic data support for the construction of temperature-pressure coupled control equations by determining the contribution of multiple mechanism source terms, the average total stress increment, and the temperature change. It clarifies the quantitative source of each component term in the equations and eliminates the basic data deviation in the equation construction. The temperature-pressure coupled control equations constructed based on core parameters and pore elastic parameters realize a unified quantitative expression of the pore pressure increment by stress, temperature, and multiple mechanism source terms, accurately reflecting the coupled influence of each factor on formation pore pressure.

[0092] Figure 4 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 3 ,like Figure 4 As shown, this embodiment, based on the above embodiments, provides a detailed explanation of the specific determination process of the hydraulic diffusion coefficient and the closure-depressurization timescale, including:

[0093] S401. Determine the hydraulic diffusion coefficient based on the rock permeability, porosity, fluid viscosity, and total compressibility in the closed-release related parameters.

[0094] In this embodiment, the expression for the hydraulic diffusion coefficient is as follows:

[0095]

[0096] Among them, D h Here, k is the hydraulic diffusion coefficient, and k is the rock permeability. Porosity c is the fluid viscosity. t For total compressibility.

[0097] First, the rock permeability, porosity, fluid viscosity, and total compressibility in the closed-off-depressurization related parameters are uniformly calibrated to ensure that the dimensions of each parameter match the calculation requirements. Then, the calibrated parameters are substituted into the expression of the hydraulic diffusion coefficient for numerical calculation to obtain the specific quantitative value of the hydraulic diffusion coefficient, which directly reflects the diffusion and transmission capacity of pore pressure in the formation.

[0098] Optionally, the total compressibility c needs to be confirmed before calculation. t The unit is the reciprocal of Pascal (Pa). -1It can be obtained by converting the equivalent compressibility coefficient of pore fluid, the pore volume compressibility coefficient, and the compressibility coefficient of solid particles:

[0099]

[0100] Specifically, select typical rock permeability of shale (e.g., 1.0 × 10⁻⁶). -22 Parameters such as square meters and porosity (e.g., 0.08) are substituted into the formula for calculation. Multiple significant figures are retained in the calculation to avoid the loss of accuracy caused by numerical rounding and to ensure that the results are consistent with the seepage characteristics of mudstone and shale formations.

[0101] S402. Determine the closure-depression timescale based on the hydraulic diffusion coefficient and the drainage characteristic length in the closure-depression related parameters.

[0102] In this embodiment, the expression for the sealing-depressurization time scale is as follows:

[0103]

[0104] in, The timescale is defined as closure-depression, where L is the characteristic length of the drainage, and D... h is the hydraulic diffusion coefficient.

[0105] First, extract the drainage characteristic length from the calculated hydraulic diffusion coefficient and the closure-relief related parameters. Then, verify the unit consistency of the two parameters to ensure that the units of the length and diffusion coefficient match. Next, substitute them into the expression of the closure-relief time scale for numerical derivation calculation to obtain the specific value of the closure-relief time scale. This parameter characterizes the rate of pressure relief in formation pores.

[0106] Optionally, the drainage characteristic length can be taken as half the thickness of the target mudstone and shale layer or the shortest distance to the drainage boundary. For example, a typical drainage characteristic length of 200 meters for such mudstone and shale can be selected and substituted into the hydraulic diffusion coefficient calculation. The result is first obtained in seconds and then converted to the geologically common time unit of millions of years (Ma). The standard unit conversion rules are strictly followed throughout the process to avoid calculation deviations caused by inconsistent units and to ensure numerical accuracy.

[0107] The pore pressure treatment method for shale formations provided in this application calculates the hydraulic diffusion coefficient based on sealing-relief parameters such as rock permeability, accurately quantifying the pore pressure diffusion capacity of the formation. This provides core quantitative parameters of seepage characteristics for subsequent pore pressure relief calculations, avoiding calculation errors caused by qualitative analysis of pore pressure diffusion capacity. By combining drainage characteristic length and hydraulic diffusion coefficient to calculate the sealing-relief time scale, the temporal characteristics of pore pressure relief in the formation are clarified, providing accurate time dimension quantitative basis for the calculation of relief weights, making subsequent relief correction calculations more consistent with actual geological seepage conditions.

[0108] Figure 5 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 4 ,like Figure 5 As shown, this embodiment, based on the above embodiments, provides a detailed explanation of the calculation process for the target pore pressure increment, including:

[0109] S501. Determine the corresponding drainage end element based on the target mudstone and shale formation.

[0110] In this embodiment, the drainage end-unit is the pressure state end-unit corresponding to when the fluid can be freely discharged during the sealing-depressurization process of the target mudstone and shale formation.

[0111] Based on the geological structure and seepage boundary characteristics of the target shale formation, the pressure state end-unit corresponding to the free discharge of fluid during the closure-decompression process is determined, which is the drainage end-unit. The definition of this end-unit needs to be based on whether there are lateral, fractured connecting boundaries or high-permeability sand bodies or other drainage channels in the target shale formation.

[0112] Optionally, the sedimentary framework and structural features of the strata to be investigated for drainage end-units should be defined to confirm whether there are channels for free fluid discharge such as high-permeability interconnected layers and fault zones. Corresponding drainage end-units should be set according to the zonal geological characteristics of the strata, so that the drainage end-units are set to fit the actual geological conditions for fluid discharge of the strata.

[0113] S502. Based on multi-source data, determine the corresponding hydrostatic pressure control increment and the density of the connected fluid column.

[0114] Based on multi-source data of the target mudstone and shale formation, key parameters such as burial depth and basic density of formation fluids are extracted. The hydrostatic pressure control increment is derived through hydrostatic pressure correlation calculation formula. At the same time, based on fluid property data and formation fluid connectivity characteristics, the actual density value of the connected fluid column in the formation is determined.

[0115] Optionally, the hydrostatic pressure control increment is calculated by selecting core parameters such as formation water density, and then calculating it using a dedicated formula in conjunction with the change in formation depth. The density of the connected fluid column needs to be determined by comprehensively measuring the oil, gas, and water densities in the fluid property data, combined with the actual distribution characteristics of the formation fluid.

[0116] S503. Determine the pressure increment of the drainage end element based on the hydrostatic pressure control increment, or select the end element increment corresponding to the pressure gradient of the oil column or gas column as the pressure increment of the drainage end element based on the density of the connected fluid column.

[0117] First, determine the fluid connectivity type of the target mudstone and shale formation. If the formation is connected by water, the hydrostatic pressure control increment is directly used as the pressure increment of the drainage end-unit. If it is connected by oil or gas columns, the matching oil or gas column pressure gradient is selected based on the determined density of the connected fluid column, and the corresponding end-unit increment is calculated as the pressure increment of the drainage end-unit.

[0118] Optionally, before determining the pressure increment of the drainage end-member, it is necessary to verify the fluid communication medium type of the formation. When water is connected, the hydrostatic pressure is directly used to control the increment. When oil and gas columns are connected, the specific pressure gradient is calculated according to the corresponding fluid column density, and then the corresponding end-member increment is calculated in combination with the vertical scale of the formation.

[0119] S504. Based on the pressure relief weight, the contribution of the multi-mechanism source terms is corrected to obtain the corrected contribution of the multi-mechanism source terms.

[0120] The calculated pressure relief weight is used as the closure-pressure relief correction coefficient, and multiplied numerically with the contribution of the multi-mechanism source terms. This operation eliminates the source term loss caused by fluid discharge, thus completing the correction of the contribution of the multi-mechanism source terms and obtaining the corrected contribution of the multi-mechanism source terms.

[0121] Specifically, the pressure relief weight is calculated using an exponential function formula. This value is then applied to the contribution of each sub-item source, such as negative compaction, hydrocarbon generation, and crude oil cracking, and the corrections are completed. Finally, the corrected contribution of each sub-item source is summed to obtain the overall corrected multi-mechanism source contribution.

[0122] S505. Based on the modified multi-mechanism source term contribution, stress term coefficient, thermal term coefficient, average total stress increment, temperature change, and temperature-pressure coupled control equation, determine the pore pressure increment under near-closed conditions.

[0123] The corrected contribution of the multi-mechanism source terms, along with the average total stress increment, temperature change, and stress and thermal coefficients in the pore elastic parameters, are substituted into the temperature-pressure coupling control equation. The numerical calculation is then performed step by step according to the operational logic of the temperature-pressure coupling control equation to obtain the pore pressure increment of the target shale formation under near-closed conditions.

[0124] S506. Based on the pore pressure increment in the near-closed state, the pressure increment of the drainage end element, and the pressure relief weight, obtain the pore pressure increment at the target time step.

[0125] For example, the pressure relief weight is numerically calculated with the pore pressure increment in the near-closed state and the pressure increment of the drainage end element. First, the product of the pressure relief weight and the pore pressure increment in the near-closed state is calculated. Then, the product of 1 minus the pressure relief weight and the pressure increment of the drainage end element is calculated. The two product results are added together to obtain the pore pressure increment at the target time step.

[0126] Specifically, the calculation is completed according to the end-member fusion formula. In the formula, the pressure relief weight is a coefficient, and the pore pressure increment in the near-closed state and the pressure increment of the drainage end-member are the two end-member base values. The operation order of multiplication before addition is strictly followed to obtain the pore pressure increment of the target time step.

[0127] S507. The pore pressure increment at the target time step is taken as the target pore pressure increment of the target mudstone and shale formation.

[0128] The pore pressure increment of the target time step obtained by end-member fusion calculation is directly determined as the target pore pressure increment corresponding to the target mudstone and shale formation. This value is the pore pressure increment result after comprehensively considering the sealing-decompression effect and can be directly used for subsequent determination of target pore pressure.

[0129] Optionally, before determining the target pore pressure increment, it is necessary to verify the calculation process and numerical accuracy of the pore pressure increment at the target time step. After confirming that there are no calculation errors and the parameters are substituted correctly, it can be used as the final target pore pressure increment of the target mudstone and shale formation.

[0130] The pore pressure processing method for shale formations provided in this application clarifies the pressure benchmark for free fluid discharge by determining the drainage end-member, providing a reference basis that fits the geological reality for subsequent end-member increment calculations; it determines the hydrostatic pressure control increment and the density of the connected fluid column, providing accurate quantitative data support for the selection of drainage end-member pressure increments; it rationally selects the pressure increment of the drainage end-member, ensuring the adaptability of the end-member pressure state to the formation fluid connectivity type; it corrects the contribution of multiple mechanism source terms, eliminating the source term loss caused by pressure relief, making the source term contribution more consistent with the actual geological conditions of the formation; it calculates the near-closed pore pressure increment through coupled equations, achieving accurate quantification of pore pressure increment under multi-factor coupling; it integrates the two end-member increments to obtain the time-step pore pressure increment, comprehensively considering the closure and pressure relief effects, and conforming to the actual pressure evolution process of the formation; it determines the target pore pressure increment, providing the core quantitative basis for the final formation pore pressure calculation, ensuring the accuracy of subsequent pressure determination.

[0131] Figure 6A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 5 ,like Figure 6 As shown, this embodiment elaborates on the determination process of the contribution of multiple mechanism source terms based on the above embodiments. The overpressure mechanism includes negative compaction mechanism, hydrocarbon generation pressurization mechanism, crude oil cracking pressurization mechanism, tectonic uplift unloading mechanism, and thermal flow disturbance mechanism. Correspondingly, the determination process includes:

[0132] S601. Based on well logging data and formation burial history data, determine the corresponding burial rate, structural uplift amplitude, and uplift rate.

[0133] Key information such as density, depth, and lithology is extracted from well logging data. Combined with records of burial evolution stages and uplift processes in stratigraphic burial history data, the burial rate is calculated by the relationship between geological time and burial depth. The tectonic uplift amplitude is determined by the stratigraphic erosion thickness in stratigraphic burial history data. The uplift rate is then calculated by converting the tectonic uplift amplitude and the corresponding geological duration. These parameters form the basis for subsequent overpressure mechanism calculations.

[0134] Specifically, the well logging data is first preprocessed by depth registration and anomaly removal. Combined with sedimentary cycle analysis of stratigraphic burial history data, a curve of burial depth change over geological time is plotted. The burial rate is calculated based on the change in burial depth per unit geological time. The tectonic uplift amplitude is determined by the difference between the erosion surface and the original burial depth. The uplift rate is the ratio of the uplift amplitude to the uplift duration.

[0135] S602. Determine the first pore pressure increment corresponding to the negative compaction mechanism based on the burial rate and the sealing-decompression time scale.

[0136] First, the burial rate is converted into a uniform time unit. Then, the loading rate is calculated by introducing the loading-to-pore pressure ratio coefficient in combination with the closure-decompression time scale. Finally, the loading rate is substituted into the calculation formula of negative compaction pressurization to obtain the first pore pressure increment corresponding to the negative compaction mechanism considering the decompression effect. This increment reflects the pressurization effect of uneven compaction.

[0137] Specifically, the burial rate is converted from millions of years per meter to the international standard unit of seconds per meter, and the pore pressure ratio coefficient is set to a reasonable value of 0-1. The pressure of the overlying strata is calculated based on density and gravitational acceleration. The first pore pressure increment is obtained by solving the first-order attenuation equation in combination with the sealing-depressurization time scale.

[0138] S603. Based on geochemical data and stratigraphic thermal history data, determine the corresponding convertible kerogen mass, conversion rate increment, hydrocarbon generation volume source term, and net pyrolysis volume source term.

[0139] Information such as total organic carbon, hydrogen index, and maturity index is extracted from geochemical data. Combined with the temperature evolution characteristics of stratigraphic thermal history data, the mass of convertible kerogen is quantitatively calculated. The conversion rate increment is calculated by the kinetic model. Then, based on the oil and gas volume factor and density, the hydrocarbon generation volume source term is calculated. When the maturity reaches the oil cracking stage, the net cracking volume source term is calculated.

[0140] Specifically, the total organic carbon mass fraction of the statistical strata is calculated, and the convertible kerogen mass per unit volume is calculated in combination with rock density and porosity. The conversion rate increment is obtained through a first-order reaction kinetic model based on the formation temperature evolution. The hydrocarbon generation volume source term is converted according to the product distribution coefficient, and the net cracking volume source term deducts the crude oil phase volume and includes the cracking product volume increment.

[0141] S604. Based on the convertible kerogen mass, conversion rate increment, and hydrocarbon generation volume source term, determine the second pore pressure increment corresponding to the hydrocarbon generation pressurization mechanism.

[0142] The converted kerogen mass is obtained by multiplying the convertible kerogen mass by the conversion rate increment. The mass is then normalized by combining the ratio of the hydrocarbon generation volume source term to the pore fluid volume. This normalized value is then substituted into the hydrocarbon generation pressurization calculation formula. By combining the elastic parameters of the pore fluid and the skeleton, the second pore pressure increment corresponding to the hydrocarbon generation pressurization mechanism is obtained.

[0143] Specifically, first calculate the kerogen conversion mass, normalize the hydrocarbon generation volume source term, calculate the combined denominator by combining the pore fluid equivalent compressibility coefficient and the pore volume compressibility coefficient, take the retention coefficient as 1 under closed conditions, and calculate the second pore pressure increment according to the hydrocarbon generation pressurization formula.

[0144] Among them, the retention coefficient is used in conjunction with the technical logic of quantitative recovery of shale formation pressure. The range of values ​​is This coefficient characterizes the effective retention ratio of the hydrocarbon generation volume source term. Its value directly reflects the degree to which the volume of fluid generated by hydrocarbon generation is retained within the shale porosity system. A larger value indicates greater retention and a more significant hydrocarbon generation pressurization effect; conversely, a smaller value indicates more complete hydrocarbon expulsion / depressurization and a weaker pressurization effect. Its specific determination rules are strongly correlated with the sealing-depressurization geological conditions of the formation, and the core rules are as follows:

[0145] Rule 1: When the target shale formation is in a near-closed state, the pore fluid exhibits no hydrocarbon expulsion or pressure relief behavior during hydrocarbon generation (expulsion volume). When the geological conditions are completely closed, the retention coefficient is directly taken as a fixed value of 1. The expression for the effective hydrocarbon generation volume source term at this time is:

[0146]

[0147] in, For hydrocarbon generation volume source term, The retention coefficient, This is the net volumetric source item for hydrocarbon generation.

[0148] As shown above, there is no loss in the hydrocarbon generation volume source term, and the hydrocarbon generation pressurization effect reaches the theoretical upper limit. This is also the core basis for the aforementioned "retention coefficient of 1 under closed conditions".

[0149] Rule 2: Based on the formation sealing-decompression timescale and the geological duration of the hydrocarbon generation process, first calculate the decompression weight. In engineering practice, the retention coefficient can be used as an equivalent decompression weight, i.e. This enables the quantitative calculation of the retention coefficient, ensuring that the value closely matches the actual seepage and depressurization geological conditions of the formation.

[0150] Rule 3: When the strata are in a fully drained open state, the fluid generated by hydrocarbon generation can be freely discharged through channels such as high-permeability sand bodies and fault zones. That is, when the pressure is fully released (the geological duration is much longer than the time scale of closure-pressure release), the pressure release weight approaches 0, and the retention coefficient also approaches 0. At this time, the effective hydrocarbon generation volume source term approaches 0, and the hydrocarbon generation pressurization effect is almost negligible.

[0151] Rule 4: When the stratum is in a transitional state between closure and depressurization, the retention coefficient... The value is taken as a number between 0 and 1, with the specific value determined by the formation's seepage properties and drainage characteristics. The value is negatively correlated with formation permeability and positively correlated with the length of the drainage boundary; that is, the lower the permeability, the longer the distance to the drainage boundary. The closer to 1, the higher the permeability and the more developed the drainage channels. The closer it is to 0.

[0152] S605. Based on the net cracking volume source term, determine the third pore pressure increment corresponding to the crude oil cracking pressurization mechanism.

[0153] The net cracking volume source term and the pore fluid volume are normalized, and the combined denominator is calculated by combining the pore fluid equivalent compressibility coefficient, pore volume compressibility coefficient, and solid particle compressibility coefficient. This denominator is then substituted into the specific calculation formula for crude oil cracking pressurization to obtain the third pore pressure increment corresponding to the crude oil cracking pressurization mechanism.

[0154] Specifically, the net pyrolysis volume source term is effectively retained according to the actual pressure relief state of the formation. A reasonable retention coefficient is selected to calculate the effective pyrolysis volume source term. Then, the combined denominator parameters of pore fluid and rock skeleton are calculated, and the third pore pressure increment is obtained by calculating according to the pyrolysis pressurization formula.

[0155] S606. Determine the fourth pore pressure increment corresponding to the structural uplift amplitude, uplift rate, and stress term coefficient.

[0156] The unloading increment of the total vertical stress is calculated from the structural uplift amplitude and approximated as the average total stress increment. Taking into account the time effect of stress release in combination with the uplift rate, the average total stress increment is multiplied by the stress term coefficient to obtain the fourth pore pressure increment corresponding to the structural uplift unloading mechanism. Among them, the fourth pore pressure increment is mostly a pressure reduction effect.

[0157] Specifically, the vertical total stress unloading increment is obtained by substituting the uplift amplitude into the geostress calculation formula. When the uplift rate is slow, a pressure relief weight is introduced to correct the stress release. Then, the corrected average total stress increment is multiplied by the stress term coefficient to obtain the fourth pore pressure increment.

[0158] S607. Based on formation temperature or formation thermal history data, determine the corresponding heat flow change and temperature anomaly increment, and based on the heat flow change, temperature anomaly increment, and thermal term coefficient, determine the fifth pore pressure increment corresponding to the heat flow disturbance mechanism.

[0159] Earth heat flow evolution data are extracted from formation temperature or formation thermal history data. The heat flow change is calculated, and then combined with the geothermal gradient to convert the heat flow change into temperature anomaly increment. The temperature anomaly increment is multiplied by the thermal term coefficient to obtain the fifth pore pressure increment corresponding to the heat flow disturbance mechanism.

[0160] Specifically, the change in heat flow is the difference between the original value and the changed value of the geothermal heat flow. The temperature anomaly increment is calculated by combining the geothermal gradient and the burial depth of the strata. The equivalent thermal expansion coefficient of the multiphase fluid is calculated by weighting it according to the saturation and the thermal term coefficient is solved. The two are multiplied to obtain the fifth pore pressure increment.

[0161] Figure 7 A calculation result diagram showing the decrease in formation pressure due to tectonic uplift and temperature drop in the formation, as provided in an embodiment of this application, is shown below. Figure 7 As shown, in the process of calculating the heat flow change and temperature anomaly increment using formation temperature or formation thermal history data, and then solving for the fifth pore pressure increment corresponding to the heat flow disturbance mechanism, Figure 7 To visualize the calculation results under the actual geological conditions of the target shale formation, this study visually demonstrates the specific numerical changes in formation pressure reduction at four key geological moments (65 Ma, 60 Ma, 55 Ma, and 50 Ma) caused by the thermal flow disturbance behavior resulting from the temperature drop in the formation due to tectonic uplift. It clearly reflects the quantitative results of the pressure reduction effect brought about by the thermal flow disturbance mechanism under the coupling effect of temperature anomaly increments and thermal term coefficients at different geological time steps. This also confirms that temperature changes caused by tectonic uplift are an important component of thermal flow changes, providing a practical geological time dimension reference for the calculation of the fifth pore pressure increment. Figure 7The markings such as A10, A1, A47, A2021, A6, and A138 represent the drilling numbers (i.e., well location numbers) of the target mudstone and shale formations within the X section of Basin A in the study area. These are standardized and unique identifiers for wells drilled in the study area in the field of oil and gas exploration.

[0162] It is important to note that Figure 7 This is merely an illustrative demonstration and does not affect the scope of protection of this application.

[0163] S608. Summing the increments of the first pore pressure, the second pore pressure, the third pore pressure, the fourth pore pressure, and the fifth pore pressure to obtain the contribution of the multi-mechanism source terms.

[0164] We collected five pore pressure increments corresponding to negative compaction, hydrocarbon generation pressurization, crude oil cracking pressurization, tectonic uplift unloading, and thermal flow disturbance. We first verified that the unit of all pore pressure increments was unified to megapascals, and then summed them algebraically to obtain the contribution of the multi-mechanism source term, which is the core source term of the temperature-pressure coupled control equation.

[0165] Specifically, before summing, the positive and negative values ​​of each pore pressure increment are accurately determined, with the pressure-increasing effect being positive and the pressure-reducing effect being negative. The total contribution of the multi-mechanism source terms is calculated by algebraic summation, and the numerical proportion of each sub-term of pore pressure increment is statistically analyzed. The contribution proportion data of each mechanism is output, providing a basis for the subsequent identification of the overpressure main control mechanism.

[0166] The pore pressure processing method for shale formations provided in this application determines basic geological parameters by extracting well logging and formation burial history data, laying a precise data foundation for the quantitative calculation of various overpressure mechanisms. It sequentially calculates the pore pressure increments corresponding to each overpressure mechanism, realizing the quantitative decomposition and individual calculation of different pressurization and depressurization mechanisms. The algebraic summation of the five pore pressure increments yields the contribution of multiple mechanism source terms, integrating the comprehensive effects of all overpressure mechanisms. This provides a precise and complete source term basis for the temperature-pressure coupled control equation, and the pore pressure increments of each sub-term also provide quantitative support for identifying the main overpressure control mechanism.

[0167] Figure 8 A flowchart illustrating the pore pressure treatment method for shale formations provided in this application embodiment. Figure 6 ,like Figure 8 As shown, this embodiment, based on the above embodiment, provides supplementary explanations of the subsequent process after determining the target pore pressure of the target mudstone and shale formation, including:

[0168] S801. Perform original term decomposition and weight calculation on the first pore pressure increment, second pore pressure increment, third pore pressure increment, fourth pore pressure increment and fifth pore pressure increment to determine the absolute value and proportion ranking of the contribution of each overpressure mechanism.

[0169] The original terms of the five pore pressure increments corresponding to the five overpressure mechanisms, including negative compaction and hydrocarbon generation pressurization, were decomposed. The original quantitative values ​​and positive and negative attributes of each increment were retained. Then, the proportion of each increment to the contribution of the multi-mechanism source terms was calculated by weighted calculation method. Finally, the absolute value of the contribution of each overpressure mechanism was determined, and the proportions were sorted from high to low.

[0170] Specifically, during the original item decomposition, the positive and negative values ​​of the increments of each mechanism are fully preserved. The pressure-boosting effect is a positive value, and the pressure-reducing effect is a negative value. The weight calculation is based on the absolute value of each increment. The proportion of a single mechanism is its absolute value of increment divided by the sum of the absolute values ​​of all increments. A sorting table from high to low is generated according to the proportion results, and the quantitative ledger of the contribution of each mechanism is output simultaneously.

[0171] Figure 9 The formation pressure state calculation result diagram provided for the embodiments of this application is as follows: Figure 9 As shown, in the process of performing original term decomposition and weight calculation on the pore pressure increments corresponding to five overpressure mechanisms—negative compaction, hydrocarbon generation pressurization, crude oil cracking pressurization, tectonic uplift unloading, and thermal flow disturbance— Figure 9 To visualize the calculation results at the critical geological moment of 60 Ma in the target stratigraphic segment of the study area, Figure 9 The data clearly indicates the pressure contribution values ​​of each overpressure mechanism—negative compaction pressurization, hydrocarbon generation, tectonic uplift, temperature reduction, and crude oil cracking—at the specified time point. It visually demonstrates the absolute value of each mechanism's contribution, directly reflecting the original quantitative values ​​of each increment after the original term decomposition. This provides clear and visualized data support for subsequent calculations and ranking of the contribution ratios of each mechanism based on these results, making the original term decomposition results more geologically relevant. Figure 9 The markings such as A10, A1, A47, A2021, A6, and A138 represent the drilling numbers (i.e., well location numbers) of the target mudstone and shale formations within the X section of Basin A in the study area. These are standardized and unique identifiers for wells drilled in the study area in the field of oil and gas exploration.

[0172] It is important to note that Figure 9 This is merely an illustrative demonstration and does not affect the scope of protection of this application.

[0173] S802. Based on the absolute value and proportion of the contribution of each overpressure mechanism, determine the dominant mechanism of overpressure in the target mudstone and shale formation to form the corresponding overpressure genesis discrimination result.

[0174] For example, based on the absolute value and proportion ranking of the contributions of each overpressure mechanism, the dominant mechanism of overpressure in the target shale formation is determined by combining the proportion threshold. If the proportion of a single mechanism is significantly higher than that of others, it is a single dominant mechanism; if the proportions of multiple mechanisms are similar, it is a composite dominant mechanism. After comprehensive analysis, a clear result of overpressure genesis is formed.

[0175] Specifically, the threshold for determining a single dominant mechanism is set when the proportion exceeds a set threshold (e.g., 50%). When the proportions of multiple mechanisms are all within a set range (e.g., 30%-50%), it is determined to be a composite dominant mechanism. The determination results must clearly indicate the type of dominant mechanism, the specific contribution proportion of each mechanism, and explain the trend of each mechanism's influence on pore pressure increase or decrease.

[0176] S803. Determine the hydrostatic pressure of the target mudstone and shale formation based on multi-source data.

[0177] Key parameters such as the burial depth and formation water density of the target mudstone and shale formations are extracted from multi-source data. The standard value of gravity acceleration is confirmed. The parameters are substituted into the hydrostatic pressure calculation formula to complete the numerical calculation. According to the stratification characteristics, the hydrostatic pressure values ​​corresponding to different burial depths are determined.

[0178] Specifically, the midpoint burial depth of each segment is selected as the calculation basis according to the stratification results of the target mudstone and shale strata. The formation water density is taken as the typical value measured in the multi-source data. The hydrostatic pressure is calculated as the product of formation water density, gravitational acceleration, and burial depth. Then, the unit is converted to megapascals, and the hydrostatic pressure results of each segment are output.

[0179] S804. Based on the target pore pressure and hydrostatic pressure of the target mudstone and shale formation, determine the corresponding pressure coefficient and use the pressure coefficient as the pore pressure evaluation index.

[0180] The target pore pressure of each segment of the target mudstone and shale formation is compared with the hydrostatic pressure calculated for the corresponding segment to obtain the pressure coefficient for each segment. This coefficient can intuitively characterize the degree of anomaly in the formation pore pressure and is used as the core pore pressure evaluation index for evaluating the formation pore pressure state.

[0181] Optionally, during the calculation, it is ensured that the target pore pressure and hydrostatic pressure correspond one-to-one with the layer and burial depth. The pressure state is determined according to the pressure coefficient value: a pressure coefficient greater than the hydrostatic pressure is overpressure, equal to the hydrostatic pressure is normal pressure, and less than the hydrostatic pressure is negative pressure. The pressure coefficient and the corresponding pressure state determination result are marked for each layer.

[0182] S805. The results of the overpressure genesis determination and the pore pressure evaluation index are used as the pore pressure analysis results of the target mudstone and shale formation.

[0183] The established overpressure genesis identification results are systematically integrated with pore pressure evaluation indicators. Information is sorted out according to the stratification or burial depth characteristics of the target mudstone and shale formation, so that each layer corresponds to the contribution characteristics, dominant mechanism and pressure coefficient of the overpressure mechanism. Finally, the results are integrated into a complete pore pressure analysis of the target mudstone and shale formation.

[0184] Optionally, the integration can be carried out on a per-stratum basis, with each segment clearly marked with the dominant overpressure mechanism, the contribution percentage of each mechanism, the pressure coefficient value, and the pressure state. All information can be compiled into a standardized pore pressure analysis result table, or a visual analysis result of a profile or planar view can be output.

[0185] Figure 10 A schematic diagram of the formation pressure evolution history provided for embodiments of this application, such as... Figure 10 As shown, in the process of integrating the overpressure genesis determination results and pore pressure evaluation indicators into the pore pressure analysis results of the target mudstone and shale formation, Figure 10 To visualize the time dimension of the final analysis results, Figure 10 The study comprehensively presents the pressure contribution evolution curves of various overpressure mechanisms in the target stratigraphic segment of the study area from the early to the late geological history, including negative compaction pressurization, tectonic uplift pressurization, primary hydrocarbon generation pressurization, and residual hydrocarbon cracking pressurization. It also overlays measured formation pressure curves for comparison and verification. This not only includes the contribution changes of each dominant mechanism in the overpressure genesis discrimination results at different geological times, but also reflects the actual pressure evolution state corresponding to the pore pressure evaluation index. By combining the overpressure mechanism contribution characteristics of each stratigraphic segment, the pressure state corresponding to the pressure coefficient, and the evolution law of the geological time dimension, a complete and intuitive pore pressure analysis result is formed.

[0186] It is important to note that Figure 10 This is merely an illustrative demonstration and does not affect the scope of protection of this application.

[0187] The pore pressure processing method for shale formations provided in this application achieves precise quantitative decomposition of the contribution of each overpressure mechanism by performing original term decomposition and weight calculation on the increment of each overpressure mechanism, clarifying the actual influence of each mechanism on pore pressure; it identifies the dominant overpressure mechanism and forms a discrimination result, revealing the core cause of formation overpressure and providing key causal basis for geological evolution analysis; it calculates hydrostatic pressure to provide a unified benchmark for pore pressure evaluation, eliminating benchmark bias in the evaluation process; it obtains the pressure coefficient through ratio calculation, realizing an intuitive quantitative evaluation of the degree of pore pressure anomaly; and it integrates the two types of results to form pore pressure analysis results, providing a systematic and comprehensive pore pressure analysis conclusion, and providing a complete quantitative basis for subsequent related engineering applications.

[0188] Figure 11 This is a schematic diagram of the pore pressure treatment device for shale formations provided in an embodiment of this application. The device in this embodiment can be in the form of software and / or hardware. For example... Figure 11As shown in the embodiment of this application, the pore pressure processing device 1100 for shale formations is applied to a computer device. The device includes: an acquisition module 1101, a first processing module 1102, a second processing module 1103, a third processing module 1104, a construction module 1105, a calculation module 1106, and a fourth processing module 1107.

[0189] The acquisition module 1101 is used to receive the target shale formation related acquisition instructions uploaded by the user through a preset interactive interface, and to acquire multi-source data and geological process duration of the target shale formation according to the target shale formation related acquisition instructions; wherein, the multi-source data includes at least one or more of the following types: well logging data, formation temperature or formation thermal history data, geochemical data, rock physical property data, fluid physical property data, formation burial history data, and pressure measurement or verification data;

[0190] The first processing module 1102 is used to determine the pore elastic parameters and sealing-decompression related parameters of the target mudstone and shale formation based on multi-source data.

[0191] The second processing module 1103 is used to determine the corresponding hydraulic diffusion coefficient and the closure-decompression time scale based on the closure-decompression related parameters.

[0192] The third processing module 1104 is used to determine the corresponding depressurization weight based on the closure-depressurization timescale and the duration of the geological process;

[0193] Module 1105 is used to construct temperature-pressure coupled control equations based on multi-source data and pore elastic parameters. The temperature-pressure coupled control equations express stress, temperature and multi-mechanism source terms as superposition terms of pore pressure increments.

[0194] Calculation module 1106 is used to calculate the corresponding target pore pressure increment based on the pressure relief weight and the temperature-pressure coupling control equation;

[0195] The fourth processing module 1107 is used to determine the target pore pressure of the target mudstone and shale formation based on the target pore pressure increment.

[0196] In one possible implementation, the first processing module 1102 is also used for the hole elastic parameters:

[0197] The pore elastic parameters include the thermal expansion coefficient of the shale skeleton, the pore volume compressibility coefficient, the solid particle compressibility coefficient, the pore fluid equivalent thermal expansion coefficient, the pore fluid equivalent compressibility coefficient, the stress term coefficient, and the thermal term coefficient; the closure-decompression related parameters include rock permeability, porosity, fluid viscosity, total compressibility, and drainage characteristic length.

[0198] In one possible implementation, the first processing module 1102 is further configured to:

[0199] Deep registration, anomaly removal, stratification, and statistical processing are performed on multi-source data to obtain processed multi-source data.

[0200] In one possible implementation, the building module 1105 is further configured to:

[0201] Based on multi-source data, the corresponding contribution of multi-mechanism source terms, average total stress increment, and temperature change are determined. Among them, the contribution of multi-mechanism source terms is the sum of the pore pressure increments corresponding to multiple overpressure mechanisms, and the average total stress increment is the equivalent unloading or loading stress increment.

[0202] Based on the contributions of multiple mechanistic source terms, the average total stress increment, the temperature change, and the porosity parameters, a temperature-pressure coupled control equation is constructed. The process expression of the temperature-pressure coupled control equation is as follows:

[0203]

[0204] in, , , B is the pore pressure increment, and B is the stress term coefficient. This represents the average total stress increment. The coefficient of thermal term, It is the product of the temperature changes. Contribution to multi-mechanism source terms; β p β is the pore volume compressibility coefficient. f β is the equivalent compressibility coefficient of the pore fluid. s Let α be the compressibility coefficient of the solid particles. f α is the equivalent thermal expansion coefficient of the pore fluid. s The coefficient of thermal expansion of the shale skeleton is given.

[0205] In one possible implementation, the second processing module 1103 is further configured to:

[0206] The hydraulic diffusion coefficient is determined based on the rock permeability, porosity, fluid viscosity, and total compressibility in the closure-relief related parameters. The expression for the hydraulic diffusion coefficient is as follows:

[0207]

[0208] Among them, D h Here, k is the hydraulic diffusion coefficient, and k is the rock permeability. Porosity c is the fluid viscosity. t For overall compressibility;

[0209] Based on the hydraulic diffusion coefficient and the drainage characteristic length in the closure-relief related parameters, the closure-relief time scale is determined. The expression for the closure-relief time scale is as follows:

[0210]

[0211] in, The timescale is defined as closure-depression, where L is the characteristic length of the drainage, and D... h is the hydraulic diffusion coefficient.

[0212] In one possible implementation, the third processing module 1104 is further configured to:

[0213] Based on the closure-decompression timescale and the duration of the geological process, the corresponding decompression weights are determined, including:

[0214] Based on the closure-decompression timescale and the duration of the geological process, the decompression weight is determined using a preset exponential function; the expression for the decompression weight is as follows:

[0215]

[0216] Where w is the pressure relief weight and t is the duration of the geological process. This is the closure-decompression timescale.

[0217] In one possible implementation, the computing module 1106 is further configured to:

[0218] Based on the target shale formation, determine the corresponding drainage end element; where the drainage end element is the pressure state end element corresponding to when the fluid can be freely discharged during the sealing-depressurization process of the target shale formation;

[0219] Based on multi-source data, determine the corresponding hydrostatic pressure control increment and the density of the connected fluid column;

[0220] The pressure increment of the drainage end element is determined based on the hydrostatic pressure control increment, or the end element increment corresponding to the pressure gradient of the oil column or gas column is selected as the pressure increment of the drainage end element based on the density of the connected fluid column.

[0221] Based on the pressure relief weight, the contribution of the multi-mechanism source terms is corrected to obtain the corrected contribution of the multi-mechanism source terms.

[0222] Based on the modified multi-mechanism source term contribution, stress term coefficient, thermal term coefficient, average total stress increment, temperature change, and temperature-pressure coupled control equation, the pore pressure increment under near-closed conditions is determined.

[0223] The pore pressure increment at the target time step is obtained based on the pore pressure increment under near-closed conditions, the pressure increment of the drainage end element, and the pressure relief weight.

[0224] The pore pressure increment at the target time step is taken as the target pore pressure increment of the target mudstone and shale formation.

[0225] In one possible implementation, the overpressure mechanism includes negative compaction mechanism, hydrocarbon generation pressurization mechanism, crude oil cracking pressurization mechanism, tectonic uplift unloading mechanism, and thermal flow disturbance mechanism;

[0226] Accordingly, the building module 1105 is also used for:

[0227] Based on well logging data and stratigraphic burial history data, determine the corresponding burial rate, tectonic uplift amplitude, and uplift rate;

[0228] The first pore pressure increment corresponding to the negative compaction mechanism is determined based on the burial rate and the closure-decompression time scale.

[0229] Based on geochemical data and stratigraphic thermal history data, the corresponding convertible kerogen mass, conversion rate increment, hydrocarbon generation volume source term, and net cracking volume source term were determined.

[0230] The second pore pressure increment corresponding to the hydrocarbon generation pressurization mechanism is determined based on the convertible kerogen mass, conversion rate increment, and hydrocarbon generation volume source term.

[0231] Based on the net cracking volume source term, determine the third pore pressure increment corresponding to the crude oil cracking pressurization mechanism;

[0232] The fourth pore pressure increment corresponding to the tectonic uplift unloading mechanism is determined based on the tectonic uplift amplitude, uplift rate, and stress term coefficient.

[0233] Based on formation temperature or formation thermal history data, determine the corresponding heat flow changes and temperature anomaly increments;

[0234] The fifth pore pressure increment corresponding to the heat flow disturbance mechanism is determined based on the heat flow change, temperature anomaly increment, and thermal term coefficient.

[0235] The increments of the first, second, third, fourth, and fifth pore pressures are summed to obtain the contribution of the multi-mechanism source terms.

[0236] In one possible implementation, the fourth processing module 1107 is further configured to:

[0237] The original terms of the pressure increments in the first, second, third, fourth, and fifth pores are decomposed and weighted to determine the absolute value and proportion of each overpressure mechanism's contribution.

[0238] Based on the absolute value and proportion of each overpressure mechanism's contribution, the dominant mechanism of overpressure in the target shale formation is determined to form the corresponding overpressure genesis discrimination results;

[0239] Based on multi-source data, the hydrostatic pressure of the target mudstone and shale formation was determined;

[0240] Based on the target pore pressure and hydrostatic pressure of the target mudstone and shale formation, the corresponding pressure coefficient is determined and used as the pore pressure evaluation index.

[0241] The results of overpressure genesis determination and pore pressure evaluation index were used as the pore pressure analysis results of the target mudstone and shale formation.

[0242] The pore pressure treatment device for mudstone and shale formations provided in this embodiment can perform the method provided in the above-described method embodiment. Its implementation principle and technical effect are similar, and will not be described in detail here.

[0243] Figure 12 A schematic diagram of the pore pressure treatment device for shale formations provided in this application embodiment. Figure 12 As shown, the pore pressure treatment device 1200 for shale formations provided in this embodiment includes at least one processor 1201 and a memory 1202. Optionally, the device 1200 also includes a communication component 1203. The processor 1201, memory 1202, and communication component 1203 are connected via a bus.

[0244] In a specific implementation, at least one processor 1201 executes computer execution instructions stored in memory 1202, causing at least one processor 1201 to perform the above-described method.

[0245] The specific implementation process of processor 1201 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0246] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0247] The memory may include random access memory (RAM) and may also include non-volatile memory (NVM), such as at least one disk storage device.

[0248] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0249] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0250] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0251] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0252] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0253] The division of units is merely a logical functional division; in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0254] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0255] In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0256] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0257] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0258] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A method of pore pressure management in a shale formation, characterized by, Applied to a computer device, the method includes: The system receives acquisition instructions for the target shale formation uploaded by the user through a preset interactive interface, and obtains multi-source data and geological process duration of the target shale formation according to the acquisition instructions; wherein the multi-source data includes at least one or more of the following types: well logging data, formation temperature or formation thermal history data, geochemical data, rock physical property data, fluid physical property data, formation burial history data, and pressure measurement or verification data; Based on the multi-source data, the porosity elastic parameters and sealing-decompression related parameters of the target mudstone and shale formation were determined; Based on the aforementioned closure-depressurization related parameters, determine the corresponding hydraulic diffusion coefficient and closure-depressurization time scale; The corresponding depressurization weight is determined based on the closure-depressurization timescale and the duration of the geological process; Based on the multi-source data and the pore elastic parameters, a temperature-pressure coupled control equation is constructed; wherein, the temperature-pressure coupled control equation expresses the stress effect, temperature effect and the effect of multiple mechanism source terms as a superposition term of pore pressure increment; Calculate the corresponding target pore pressure increment based on the pressure relief weight and the temperature-pressure coupling control equation; The target pore pressure of the target mudstone shale formation is determined based on the target pore pressure increment.

2. The method of claim 1, wherein, The pore elastic parameters include the thermal expansion coefficient of the shale skeleton, the pore volume compressibility coefficient, the solid particle compressibility coefficient, the pore fluid equivalent thermal expansion coefficient, the pore fluid equivalent compressibility coefficient, the stress term coefficient, and the thermal term coefficient; the closure-decompression related parameters include rock permeability, porosity, fluid viscosity, total compressibility, and drainage characteristic length.

3. The method of claim 2, wherein, Before determining the porosity elastic parameters and closure-decompression correlation parameters of the target shale formation based on the multi-source data, the method further includes: The multi-source data is subjected to deep registration, anomaly removal, stratification, and statistical processing to obtain the processed multi-source data.

4. The method of claim 3, wherein, The temperature-pressure coupled control equations are obtained as follows: Based on the multi-source data, the corresponding contribution of multi-mechanism source terms, average total stress increment, and temperature change are determined. The contribution of multi-mechanism source terms is the sum of the pore pressure increments corresponding to multiple overpressure mechanisms, and the average total stress increment is the equivalent unloading or loading stress increment. Based on the contribution of the multiple mechanism source terms, the average total stress increment, the temperature change, and the pore elastic parameters, a temperature-pressure coupled control equation is constructed. The process expression of the temperature-pressure coupled control equation is as follows: wherein, , , is the pore pressure increment, B is a stress term coefficient, is the average total stress increment, is a thermal term coefficient, is the product of the temperature change, is the multi-mechanism source term contribution; β p is the pore volume compressibility, β f is the pore fluid equivalent compressibility, β s is the solid grain compressibility, α f is the pore fluid equivalent thermal expansion coefficient, α s is the shale matrix thermal expansion coefficient.

5. The method of claim 4, wherein, The step of determining the corresponding hydraulic diffusion coefficient and the closure-relief time scale based on the closure-relief related parameters includes: The hydraulic diffusion coefficient is determined based on the rock permeability, porosity, fluid viscosity, and total compressibility among the closed-loop-depressurization related parameters. The expression for the hydraulic diffusion coefficient is as follows: where D h is the hydraulic diffusivity, k is the rock permeability, is the porosity, is the fluid viscosity, c t is the total compressibility; Based on the hydraulic diffusion coefficient and the drainage characteristic length in the closure-relief related parameters, the closure-relief time scale is determined, and the expression for the closure-relief time scale is as follows: wherein, is the closure-relief timescale, L is the drainage characteristic length, D h is the hydraulic dispersion coefficient.

6. The method according to any one of claims 1 to 5, characterized in that, The determination of the corresponding depressurization weight based on the closure-depressurization timescale and the duration of the geological process includes: Based on the closure-decompression timescale and the duration of the geological process, the decompression weight is determined using a preset exponential function; the expression for the decompression weight is as follows: where w is the pressure relief weight, t is the geologic process duration, is the closure-pressure relief timescale.

7. The method of claim 5, wherein, The step of calculating the corresponding target pore pressure increment based on the pressure relief weight and the temperature-pressure coupling control equation includes: Based on the target shale formation, the corresponding drainage end element is determined; wherein, the drainage end element is the pressure state end element corresponding to when the fluid can be freely discharged during the sealing-depressurization process of the target shale formation; Based on the multi-source data, determine the corresponding hydrostatic pressure control increment and the density of the connected fluid column; The pressure increment of the drainage end element is determined based on the hydrostatic pressure control increment, or the end element increment corresponding to the pressure gradient of the oil column or gas column is selected as the pressure increment of the drainage end element based on the density of the connected fluid column. Based on the pressure relief weight, the contribution of the multi-mechanism source terms is corrected to obtain the corrected contribution of the multi-mechanism source terms. Based on the modified multi-mechanism source term contribution, the stress term coefficient, the thermal term coefficient, the average total stress increment, the temperature change, and the temperature-pressure coupled control equation, the pore pressure increment under near-closed conditions is determined. The pore pressure increment at the target time step is obtained based on the pore pressure increment in the near-closed state, the pressure increment of the drainage end element, and the pressure relief weight. The pore pressure increment at the target time step is taken as the target pore pressure increment of the target mudstone and shale formation.

8. The method of claim 7, wherein, The overpressure mechanisms include negative compaction mechanism, hydrocarbon generation pressurization mechanism, crude oil cracking pressurization mechanism, tectonic uplift unloading mechanism, and thermal flow disturbance mechanism; Accordingly, determining the contribution of the corresponding multi-mechanism source terms based on the multi-source data includes: Based on the well logging data and the formation burial history data, determine the corresponding burial rate, structural uplift amplitude, and uplift rate; Based on the burial rate and the sealing-decompression timescale, determine the first pore pressure increment corresponding to the negative compaction mechanism; Based on the geochemical data and the stratigraphic thermal history data, the corresponding convertible kerogen mass, conversion rate increment, hydrocarbon generation volume source item, and net pyrolysis volume source item are determined. The second pore pressure increment corresponding to the hydrocarbon generation pressurization mechanism is determined based on the convertible kerogen mass, the conversion rate increment, and the hydrocarbon generation volume source term. Based on the net cracking volume source term, determine the third pore pressure increment corresponding to the crude oil cracking pressurization mechanism; The fourth pore pressure increment corresponding to the structural lifting unloading mechanism is determined based on the structural lifting amplitude, the lifting rate, and the stress term coefficient. Based on the formation temperature or formation thermal history data, determine the corresponding heat flow change and temperature anomaly increment; The fifth pore pressure increment corresponding to the heat flow disturbance mechanism is determined based on the heat flow change, the temperature anomaly increment, and the thermal term coefficient. The first pore pressure increment, the second pore pressure increment, the third pore pressure increment, the fourth pore pressure increment, and the fifth pore pressure increment are summed to obtain the contribution of the multi-mechanism source term.

9. The method of claim 8, wherein, After determining the target pore pressure of the target mudstone shale formation based on the target pore pressure increment, the method further includes: The first pore pressure increment, the second pore pressure increment, the third pore pressure increment, the fourth pore pressure increment, and the fifth pore pressure increment are decomposed and weighted to determine the absolute value and proportion of each overpressure mechanism contribution. Based on the absolute value and proportion of the contribution of each overpressure mechanism, the dominant mechanism of overpressure in the target mudstone and shale formation is determined to form the corresponding overpressure genesis discrimination result. Based on the multi-source data, the hydrostatic pressure of the target mudstone and shale formation is determined; Based on the target pore pressure and hydrostatic pressure of the target mudstone shale formation, the corresponding pressure coefficient is determined, and the pressure coefficient is used as the pore pressure evaluation index. The results of the overpressure origin determination and the pore pressure evaluation index are used as the pore pressure analysis results of the target mudstone and shale formation.

10. A pore pressure management apparatus for a shale formation, comprising: Applied to computer equipment, the device includes: The acquisition module is used to receive the target shale formation related acquisition instructions uploaded by the user through a preset interactive interface, and to acquire multi-source data and geological process duration of the target shale formation according to the target shale formation related acquisition instructions; wherein, the multi-source data includes at least one or more of the following types: well logging data, formation temperature or formation thermal history data, geochemical data, rock physical property data, fluid physical property data, and measured or verified pressure data; The first processing module is used to determine the pore elastic parameters and sealing-decompression related parameters of the target mudstone and shale formation based on the multi-source data. The second processing module is used to determine the corresponding hydraulic diffusion coefficient and the closure-decompression time scale based on the closed-decompression related parameters. The third processing module is used to determine the corresponding depressurization weight based on the closure-depressurization timescale and the duration of the geological process; A construction module is used to construct a temperature-pressure coupled control equation based on the multi-source data and the pore elastic parameters; wherein, the temperature-pressure coupled control equation expresses the stress effect, temperature effect and the effect of multiple mechanism source terms as a superposition term of pore pressure increment; The calculation module is used to calculate the corresponding target pore pressure increment based on the pressure relief weight and the temperature-pressure coupling control equation; The fourth processing module is used to determine the target pore pressure of the target mudstone shale formation based on the target pore pressure increment.

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