CN107366534B

CN107366534B - Method and device for determining coarsening permeability

Info

Publication number: CN107366534B
Application number: CN201710680971.9A
Authority: CN
Inventors: 汪斌; 黄继新; 刘尚奇; 刘洋; 罗艳艳; 韩彬; 梁光跃
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2017-08-10
Filing date: 2017-08-10
Publication date: 2020-08-11
Anticipated expiration: 2037-08-10
Also published as: CN107366534A

Abstract

The embodiment of the application provides a determination method and a determination device for coarsening permeability, wherein the method comprises the following steps: acquiring core data and logging data of a target well; determining the median value of the sandstone granularity according to the logging data; determining the horizontal permeability of the sandstone and the vertical permeability of the sandstone according to the median of the sandstone granularity and the data of the core plug sample; and under the condition that the target well is the coring well, according to the horizontal permeability of the sandstone and the vertical permeability of the sandstone, and with preset pressure as a boundary condition, respectively determining coarsening horizontal permeability and coarsening vertical permeability by using an equivalent seepage method. According to the scheme, the seepage characteristics of the permeability in different directions are considered, unfixed preset pressure is used as a boundary, a real reservoir seepage environment is simulated by using an equivalent seepage method, and the coarsening horizontal permeability and the vertical permeability are determined. Therefore, the technical problems of inaccurate coarsening horizontal permeability and vertical permeability and low reliability in the existing method are solved.

Description

Method and device for determining coarsening permeability

Technical Field

The application relates to the technical field of oil and gas exploration and development, in particular to a method and a device for determining coarsening permeability.

Background

In the process of specific exploration and development of the oil reservoir in the target area, a numerical model about the reservoir in the target area is often required to be established, and the reservoir is specifically evaluated by using the numerical model, so that the oil reservoir can be further explored and developed in the target area according to the evaluation result.

In practice, in order to build the numerical model about the reservoir in the target region, it is usually necessary to determine the permeability of the reservoir. At present, the existing method often does not fully consider the specific influence of reservoir heterogeneity on permeability anisotropy (namely permeability in different directions), and does not design corresponding model solution by combining specific characteristics of the target region stratum and flow characteristics in different directions. In most implementations, fixed boundary conditions are set, and the harmonic mean is determined as the vertical permeability simply by taking the arithmetic mean as the corresponding horizontal permeability. The technical problems of inaccurate determined horizontal permeability and vertical permeability and low reliability often exist in the concrete implementation of the existing method.

In view of the above problems, no effective solution has been proposed.

Disclosure of Invention

The embodiment of the application provides a coarsening permeability determining method and a coarsening permeability determining device, and aims to solve the technical problems that the determined horizontal permeability and vertical permeability are inaccurate and low in reliability in the concrete implementation of the existing method.

The embodiment of the application provides a determination method for coarsening permeability, which comprises the following steps:

acquiring core data and logging data of a target well, wherein the core data comprises core plug sample data;

determining a median value of sandstone particle size according to the logging data;

determining permeability of the sandstone according to the median of the sandstone particle size and the core plug sample data, wherein the permeability of the sandstone comprises: horizontal permeability of sandstone and vertical permeability of sandstone;

determining whether the target well is a cored well;

under the condition that the target well is a coring well, determining coarsening permeability by using an equivalent seepage method according to the permeability of the sandstone and by taking preset pressure as a boundary condition, wherein the coarsening permeability comprises the following steps: coarsening horizontal permeability and coarsening vertical permeability.

In one embodiment, determining the permeability of sandstone from the median of sandstone particle size and the core plug sample data comprises:

determining the horizontal permeability of the sandstone according to the median of the sandstone particle size and the core plug sample data;

and determining the vertical permeability of the sandstone according to the horizontal permeability of the sandstone and the data of the core plug sample.

In one embodiment, determining the coarsening permeability by using an equivalent percolation method according to the permeability of the sandstone and using a preset pressure as a boundary condition comprises the following steps:

under the condition that the target well is a core well, obtaining a core image of the target well according to the core data;

gridding the rock core image, and determining the configuration relation of sandstone and mudstone in the target well according to the gridded rock core image;

respectively establishing a horizontal equivalent seepage model and a vertical equivalent seepage model by taking the preset pressure as a boundary condition according to the configuration relation of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone and the vertical permeability of the sandstone;

and determining the coarsening horizontal permeability according to the horizontal equivalent seepage model, and determining the coarsening vertical permeability according to the vertical equivalent seepage model.

In one embodiment, respectively establishing a horizontal equivalent seepage model and a vertical equivalent seepage model according to the configuration relationship of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone, and the vertical permeability of the sandstone with the preset pressure as a boundary condition, includes:

establishing a first sand model according to the configuration relation of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone and the vertical permeability of the sandstone;

and setting a first pressure at the transverse left end of the first sand-mud model, setting a second pressure at the transverse right end of the first sand-mud model, and setting the preset pressures at the longitudinal two ends of the first sand-mud model respectively as boundary conditions to obtain the horizontal equivalent seepage model.

In one embodiment, determining the coarsened horizontal permeability according to the horizontal equivalent percolation model comprises:

gridding the horizontal equivalent seepage model to obtain a plurality of first unit grids;

respectively calculating the central pressure of the first unit grid;

determining flow data of the horizontal equivalent seepage model according to the central pressure of the first unit grid;

and determining the coarsening horizontal permeability according to the flow data of the horizontal equivalent seepage model.

In one embodiment, establishing a vertical equivalent seepage model according to the configuration relationship of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone, and the vertical permeability of the sandstone with the preset pressure as a boundary condition includes:

and setting a first pressure at the longitudinal upper end of the first sand-mud model, setting a second pressure at the longitudinal lower end of the first sand-mud model, and setting the preset pressures at the two transverse ends of the first sand-mud model respectively as boundary conditions to obtain the vertical equivalent seepage model.

In one embodiment, determining the coarsened vertical permeability according to the vertical equivalent percolation model comprises:

gridding the vertical equivalent seepage model to obtain a plurality of second unit grids;

respectively calculating the central pressure of the second unit grid;

determining the flow data of the vertical equivalent seepage model according to the central pressure of the second unit grid;

and determining the coarsening vertical permeability according to the flow data of the vertical equivalent seepage model.

In one embodiment, where the target well is a non-coring well, the method comprises:

determining the shale content according to the logging data;

determining a plurality of mud-sand content ratios by using the mud content;

establishing a plurality of second sand models according to the horizontal permeability of the sandstone, the vertical permeability of the sandstone and the content ratios of the plurality of sands;

and determining the coarsening horizontal permeability and the coarsening vertical permeability by utilizing the plurality of second silt models through a sand body communication rate calculation formula based on statistics.

In one embodiment, after determining the coarsening permeability, the method includes:

according to the coarsening permeability, evaluating the reservoir stratum;

and guiding well position deployment according to the reservoir evaluation result.

The embodiment of the present application further provides a determination device for coarsening permeability, including:

the acquisition module is used for acquiring core data and logging data of a target well, wherein the core data comprises core plug sample data;

the first determination module is used for determining the median of the sandstone granularity according to the logging data;

a second determining module, configured to determine permeability of the sandstone according to the median of the sandstone particle size and the core plug sample data, where the permeability of the sandstone includes: horizontal permeability of sandstone, vertical permeability of sandstone;

a third determination module for determining whether the target well is a cored well;

a fourth determining module, configured to determine, according to the permeability of the sandstone and using a preset pressure as a boundary condition, an coarsening permeability by using an equivalent seepage method when the target well is a core well, where the coarsening permeability includes: coarsening horizontal permeability and coarsening vertical permeability.

In one embodiment, the fourth determining module comprises:

the first acquisition unit is used for acquiring a rock core image of the target well according to the rock core data;

the first determining unit is used for gridding the rock core image and determining the configuration relation of sandstone and mudstone in the target well according to the gridded rock core image;

the first establishing unit is used for respectively establishing a horizontal equivalent seepage model and a vertical equivalent seepage model according to the configuration relation of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone and the vertical permeability of the sandstone by taking the preset pressure as a boundary condition;

and the second determination unit is used for determining the coarsening horizontal permeability according to the horizontal equivalent seepage model and determining the coarsening vertical permeability according to the vertical equivalent seepage model.

In one embodiment, the apparatus further comprises a fifth determination module for determining the coarsened horizontal permeability and the coarsened vertical permeability from the permeability of the sandstone and the well log data if the target well is a non-cored well, the fifth determination module comprising:

the third determining unit is used for determining the shale content according to the logging data;

a fourth determination unit for determining a plurality of sludge-sand content ratios using the sludge content;

the second establishing unit is used for establishing a plurality of second sand models according to the horizontal permeability of the sandstone, the vertical permeability of the sandstone and the content ratios of the plurality of sands;

and the fifth determining unit is used for determining the coarsening horizontal permeability and the coarsening vertical permeability according to a sand body communication rate calculation formula based on statistics by utilizing the plurality of second sand models.

In the embodiment of the application, the seepage characteristics of the permeability in different directions in the reservoir are considered, the preset pressure with a non-fixed numerical value is used as a boundary condition, the real reservoir seepage environments in different flowing directions are simulated by using an equivalent seepage method, and then the real coarsening horizontal permeability and coarsening vertical permeability can be respectively determined. Therefore, the technical problems that the determined coarsening horizontal permeability and coarsening vertical permeability are inaccurate and low in reliability in the existing method are solved, and the technical effect that coarsening permeabilities in different directions can be accurately determined is achieved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, it is obvious that the drawings in the following description are only some embodiments described in the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without any creative effort.

FIG. 1 is a process flow diagram of a method for determining coarsening permeability provided in accordance with an embodiment of the present application;

fig. 2 is a cross-correlation diagram of a GR log obtained by applying the coarsening permeability determination method provided in the embodiment of the present application and a median value of sandstone particle size;

fig. 3 is a cross-correlation diagram of the median particle size and the horizontal permeability of sandstone obtained by applying the determination method of coarsening permeability provided by the embodiment of the present application;

FIG. 4 is a schematic diagram of an equivalent flow profile obtained by applying the permeability coarsening determination method/apparatus provided in the embodiments of the present application;

FIG. 5 is a schematic view of a horizontal equivalent percolation model obtained by applying the method/apparatus for determining rough permeability provided in the embodiments of the present application;

FIG. 6 is a schematic view of a vertical equivalent percolation model obtained by applying the method/apparatus for determining rough permeability provided in the embodiments of the present application;

FIG. 7 is a schematic diagram illustrating a relationship between permeability and shale content obtained by applying the method/apparatus for determining permeability for coarsening provided by the embodiment of the present application;

FIG. 8 is a block diagram illustrating the components of a permeability coarsening determination apparatus provided in accordance with an embodiment of the present application;

fig. 9 is a schematic flow chart of a determination method/apparatus for coarsening permeability according to an embodiment of the present disclosure.

Detailed Description

In order to make those skilled in the art better understand the technical solutions in the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

Considering that the prior methods mostly do not carefully consider specific physical meanings and stratum environments when determining the permeability, and do not consider specific characteristics of the permeability in different directions, a fixed boundary condition is set, and an arithmetic mean is simply obtained to be used as the horizontal permeability, and a harmonic mean is obtained to be used as the vertical permeability. Therefore, the existing method often has the technical problems of inaccurate determined horizontal permeability and vertical permeability and low reliability. Aiming at the root cause of the technical problem, the method considers that the horizontal permeability and the vertical permeability can be respectively determined by an equivalent percolation method according to the specific anisotropic percolation characteristics of the reservoir permeability in the corresponding reservoir environment by combining the specific reservoir environment. Therefore, the technical problems of inaccurate determined horizontal permeability and vertical permeability and low reliability in the existing method can be solved, and the technical effect of accurately determining the permeability in different directions can be achieved.

Based on the thought, the embodiment of the application provides a determination method for coarsening permeability. Please refer to a processing flow chart of a determination method of coarsening permeability according to an embodiment of the present application shown in fig. 1. The method for determining the coarsening permeability provided by the embodiment of the application specifically comprises the following steps.

In the present embodiment, it should be noted that, in the subsequent reservoir evaluation process, in order to obtain a more accurate evaluation result, the three-dimensional fine geological model used often includes many grids, the data amount is relatively large, and is limited to the computing capability of the computer, and meanwhile, in order to improve the construction processing efficiency, it is often not suitable to directly use the specific geological information (including permeability data) in the model as the input data of the reservoir numerical simulation system in the specific implementation. Generally, the three-dimensional fine geological model needs to be merged and the like, i.e., Upscaling, to reduce the number of grid blocks in the model and increase the scale of the grid blocks, and it is required that the geological information of the three-dimensional fine geological model can be retained as much as possible by assigning values to the increased grid blocks. The geological information may specifically be a related parameter of the oil reservoir, and specifically may include a permeability corresponding to the coarsening treatment, that is, a coarsening permeability. Therefore, the reservoir where the target well is located can be evaluated relatively quickly and accurately based on the coarsened three-dimensional fine geological model and the corresponding coarsened geological information (including the coarsened permeability).

S11: obtaining core data and logging data of a target well, wherein the core data comprises core plug sample data.

In the present embodiment, the target well may be a core well or a non-core well. The core well (Cored well) is a well drilled by a core drill and a core drill in order to drill a core underground for observation, identification and analysis of experimental samples, and to directly obtain various data or parameters related to lithology, lithofacies, physical properties, oiliness and oiliness of the formation. The non-cored well location is not a well of a cored well.

In this embodiment, the log data may specifically include a plurality of logs, such as a natural gamma log, a density log, a natural potential log, and so on.

In this embodiment, the core plug sample may be specifically one of core samples. The Core plug sample (Core plug) may be a 5 to 10cm long, cylindrical test sample obtained from a Core. In specific implementation, corresponding core plug sample data can be obtained from the core data, and the core plug sample can also be tested separately to obtain the corresponding core sample plug data. It should be noted that, for a core well, corresponding core plug sample data may be acquired according to the core data. For non-cored wells, the core data used is from a cored well within a predetermined range of the target well, i.e., located near the target well in the same area. The acquired core plug sample data is not core plug sample data for the target well, but core plug sample data for a cored well near the target well that can better characterize the condition of the target well.

In one embodiment, the core plug sample data may be a sandstone structural sample. The sandstone structural sample is understood to be a sample which comprises predominantly sandstone and contains no or less mudstone. The main component of the sample is sandstone, so the seepage condition is simple and clear, and the sample can be used as a reference to better guide the specific analysis of the seepage condition of a specific stratum (such as a stratum with sandstone and mudstone distributed at the same time).

S12: and determining the median value of the sandstone granularity according to the logging data.

In one embodiment, determining a median value for sandstone particle size from the well log data may specifically comprise: and determining the median of the sandstone granularity according to a natural gamma logging curve (namely GR logging curve) in the logging data. Specifically, for example, according to a median intersection relationship diagram of the GR logging curve and the sandstone particle size, the median of the corresponding sandstone particle size may be determined by referring to the intersection relationship diagram of the GR logging curve and the median of the sandstone particle size, which is obtained by applying the determination method for coarsening permeability provided in the embodiment of the present application, shown in fig. 2. It should be noted that, in the embodiment of the present application, the determination of the median value of the sandstone particle size by using the natural gamma curve in the log data is only to better illustrate the embodiment of the present application. In particular, other well log data may be used to determine the median sandstone particle size, as the case may be.

S13: determining permeability of sandstone from the median of sandstone particle size and the core plug sample data, wherein the permeability of sandstone comprises: horizontal permeability of sandstone, vertical permeability of sandstone.

In one embodiment, determining the horizontal permeability of sandstone and the vertical permeability of sandstone based on the median of sandstone particle size and the core plug sample data may specifically include the following.

S13-1: and determining the horizontal permeability of the sandstone according to the median value of the sandstone particle size and the data of the core plug sample.

S13-2: and determining the vertical permeability of the sandstone according to the horizontal permeability of the sandstone and the data of the core plug sample.

In this embodiment, in a specific implementation, the core plug sample data may be specifically analyzed through an experimental test, a first corresponding relationship between a median of sandstone particle sizes and horizontal permeability of sandstone is established according to an analysis result, and the first formula based on the core plug sample data is established according to the first corresponding relationship, and is used for determining the horizontal permeability of sandstone approximately according to the median of sandstone particle sizes. And establishing a second corresponding relation between the horizontal permeability of the sandstone and the vertical permeability of the sandstone according to the analysis result, and establishing a second formula based on the core plug sample data according to the second corresponding relation, wherein the second formula is used for approximately determining the vertical permeability of the sandstone according to the horizontal permeability of the sandstone.

In the present embodiment, in order to determine the first corresponding relationship, a first formula based on the core plug sample data is established, and in the specific implementation, the following can be referred to. Performing test testing on the core plug sample data to obtain a cross relationship diagram of the median particle size and the horizontal permeability of the sandstone in the core plug sample data, and specifically, referring to the cross relationship diagram of the median particle size and the horizontal permeability of the sandstone obtained by applying the determination method of coarsening permeability provided by the embodiment of the application shown in fig. 3, determining the first corresponding relationship; and establishing a fitting formula according to the image relationship, wherein the fitting formula is used as the first formula based on the core plug sample data, and further determining the horizontal permeability of the sandstone by using the formula. In particular implementation, the first formula of the core plug-based sample may be expressed as:

y＝-0.203x²+144x-12098

in the above formula, y may be expressed as horizontal permeability of sandstone, and x may be specifically expressed as median particle size of sandstone.

In the present embodiment, in order to determine the second corresponding relationship, a second formula based on the core plug sample data is established, and in concrete implementation, the following may be referred to. For the horizontal permeability of the sandstone, the relation between the horizontal permeability and the vertical permeability of the sandstone in the core plug sample data can be determined by combining the bedding characteristics of the core plug sample data, namely a second corresponding relation; establishing a corresponding relational expression about horizontal permeability and vertical permeability of the sandstone according to the second corresponding relation, wherein the relational expression is used as a second expression based on the core plug sample data; and then the vertical permeability of the corresponding sandstone can be determined according to a second formula.

S14: determining whether the target well is a cored well.

In the embodiment, for different situations of whether the target well is the coring well, different corresponding technical schemes can be adopted to better determine the coarsening vertical permeability and the coarsening horizontal permeability of the target well. Therefore, in the present embodiment, it may be determined whether the target well is a core well according to the specific situation of the target well, so that it may be determined that the permeability of the target well in different directions is determined according to a suitable scheme.

S15: under the condition that the target well is a coring well, determining coarsening permeability respectively by using an equivalent seepage method according to the horizontal permeability of the sandstone and the vertical permeability of the sandstone and taking preset pressure as a boundary condition, wherein the coarsening permeability comprises the following steps: coarsening horizontal permeability and coarsening vertical permeability, wherein the numerical value of the preset pressure is variable rather than fixed.

In one embodiment, in order to combine different characteristics of vertical permeability and horizontal permeability in percolation according to specific reservoir conditions, an equivalent percolation method can be utilized to determine coarsened horizontal permeability and coarsened vertical permeability respectively. When implemented, the following may be included.

S15-1: and under the condition that the target well is the core well, acquiring a core image of the target well according to the core data.

In this embodiment, when the target well is a core well, the core image obtained from the core data may be the core image of the target well itself, so that the formation condition in the target well, that is, the heterogeneity of the target formation, such as the distribution condition of sandstone and mudstone, the bedding structure, and the mudstone interlayer, may be specifically analyzed according to the core image. Furthermore, the accurate seepage model established according to the formation condition (namely the heterogeneity of the formation) can be analyzed better subsequently.

S15-2: and gridding the rock core image, and determining the configuration relation of sandstone and mudstone in the target well according to the gridded rock core image.

In this embodiment, in order to make the gridded core image better reflect the arrangement concerns of sand rock and mudstone in the target well, in a specific implementation, the core image may be specifically gridded according to the bedding characteristics of the formation of the target well.

S15-3: and respectively establishing a horizontal equivalent seepage model and a vertical equivalent seepage model by taking the preset pressure as a boundary condition according to the configuration relation of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone and the vertical permeability of the sandstone.

In one embodiment, in practice, the preset pressure may be set and used in a variable-value, i.e. not fixed, value as follows: determining a value range of preset pressure according to a specific geological environment of a stratum where a target well is located; determining a plurality of values from the value range of the preset pressure as a plurality of preset pressures; respectively taking the preset pressures as boundary conditions of an equivalent seepage model to obtain a plurality of groups of corresponding coarsening permeabilities; and determining the relatively accurate coarsening permeability according to the multiple groups of coarsening permeabilities.

In this embodiment, a schematic diagram of an equivalent flow profile obtained by applying the determination method/apparatus for coarsening permeability provided in the embodiment of the present application can be specifically referred to as fig. 4. In specific implementation, according to a specific geological environment of a stratum where a target well is located, specific condition characteristics, such as pressure intensity, seepage characteristics and the like, are combined to obtain an equivalent flow profile, and then a corresponding horizontal equivalent seepage model and a corresponding vertical equivalent seepage model can be established by using the equivalent flow profile. Fig. 4 shows an equivalent flow profile corresponding to a vertical equivalent seepage model. The equivalent flow profile corresponding to the horizontal seepage model is similar to the equivalent flow profile corresponding to the vertical equivalent seepage model, and only the preset pressure setting position is opposite to the first and second pressure setting positions.

In an embodiment, establishing a horizontal equivalent seepage model according to the configuration relationship between the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone, and the vertical permeability of the sandstone, with the preset pressure as a boundary condition, may specifically include the following:

s15-3-1-1: and establishing a first sand model according to the configuration relation of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone and the vertical permeability of the sandstone.

S15-3-1-2: and setting a first pressure at the transverse left end of the first sand-mud model, setting a second pressure at the transverse right end of the first sand-mud model, and setting preset pressures at the longitudinal two ends of the first sand-mud model respectively as boundary conditions to obtain the horizontal equivalent seepage model.

Specifically, a schematic diagram of a horizontal equivalent percolation model obtained by applying the method/apparatus for determining coarsened permeability provided in the embodiment of the present application may be referred to in fig. 5. Therefore, the concrete process of the fluid in the real formation environment in the horizontal flowing process can be simulated and obtained more accurately, and the more accurate horizontal permeability can be obtained.

In an embodiment, the establishing of the vertical equivalent seepage model according to the configuration relationship between the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone, and the vertical permeability of the sandstone, with the preset pressure as a boundary condition, may specifically include the following.

S15-3-2-1: and establishing a first sand model according to the configuration relation of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone and the vertical permeability of the sandstone.

S15-3-2-2: and setting a first pressure at the longitudinal upper end of the first sand-mud model, setting a second pressure at the longitudinal lower end of the first sand-mud model, and setting preset pressures at the transverse two ends of the first sand-mud model respectively as boundary conditions to obtain the vertical equivalent seepage model.

Specifically, a schematic diagram of a vertical equivalent percolation model obtained by applying the method/apparatus for determining coarsening permeability provided by the embodiment of the present application may be referred to in fig. 6. Therefore, the concrete process of the fluid in the real formation environment in the horizontal flowing process can be simulated and obtained more accurately, and more accurate vertical permeability can be obtained.

S15-4: and determining the coarsening horizontal permeability according to the horizontal equivalent seepage model, and determining the coarsening vertical permeability according to the vertical equivalent seepage model.

In the present embodiment, the differences of the permeability in different directions, for example, the differences of the seepage characteristics, are taken into consideration, and therefore, the permeability in the corresponding direction can be determined in different equivalent seepage models.

In one embodiment, the determining the coarsened horizontal permeability according to the horizontal equivalent percolation model may specifically include the following.

S15-4-1-1: and gridding the horizontal equivalent seepage model to obtain a plurality of first unit grids.

S15-4-1-2: and respectively calculating the center pressure of each first unit grid in the plurality of first grids.

S15-4-1-3: and determining the flow data of the horizontal equivalent seepage model according to the central pressure of the first unit grids.

S15-4-1-4: and determining the coarsening horizontal permeability according to the flow data of the horizontal equivalent seepage model.

In this embodiment, in specific implementation, a preset pressure is applied to the left and right end boundaries of the horizontal equivalent seepage model. The numerical value of the preset pressure intensity is not fixed, and can be correspondingly adjusted according to specific conditions. Thus, the flow condition under the actual reservoir condition can be well characterized. In specific implementation, the preset pressure value of each first unit grid can be determined approximately by equal outward expansion according to the preset pressure given by the first unit grid at the outermost layer in the horizontal equivalent seepage model. In specific implementation, the mesh equivalent permeability in the y direction after merging can be calculated on the assumption that the fluid is incompressible. Specifically, for the first unit grid labeled (i, j), the mass conservation equation resulting from determining the corresponding steady-state condition is as follows:

in the above equation, Qx may be a flow rate at an intersection between two first unit cells in the x direction, Qy may be a flow rate at an intersection between two first unit cells in the y direction,

specifically, the first unit cell may be an intersection between the first unit cell denoted by (i, j) and the adjacent first unit cell denoted by (i +1, j), (i-1, j), (i, j +1), and (i, j-1).

In combination with the above formula, considering the flow generated by the conditions of applicability of darcy's law in the case of a fluid, a general formula of conservation of mass for each first unit cell can be formulated as follows:

a_i,jp_i,j+a_i-2,jp_i-2,j+a_i+2,jp_i+2,j+a_i,j-2p_i,j-2+a_i,j+2p_i,j+2＝0

in the above formula, a_i,jMay be a coefficient, p, preceded by an algebraic variable by the index (i, j)_i,jMay be the center pressure corresponding to the first unit cell labeled (i, j).

From the mass conservation formula above, one can determine the relationship for (n)_x,n_y) The system of equations of (1). In specific implementation, corresponding boundary conditions can be set according to specific geological conditions:

j＝0,p_i,0＝p_in

in the above formula, p_inMay be a first pressure, p_outMay be a second pressure, wherein there is a pressure difference, p, between said first pressure and said second pressure_SThe preset pressure can be preset, and in the specific implementation, the numerical value of the preset pressure (n) can be adjusted according to specific conditions_x,n_y) Reference sign, p, that can be used to characterize the first unit cell to be processed_i,jMay be the center pressure value of the first unit cell labeled (i, j).

In specific implementation, the solution of the equation set may be used to represent the central pressure value of the first unit grid labeled as (i, j), and further may calculate the flow data of the corresponding first unit grid, which may be specifically executed by referring to the following formula:

in the above formula, Q_i,jMay be the traffic data of the first unit mesh denoted by (i, j).

Then, the equivalent permeability in the y direction may be determined as the coarsening level permeability according to the flow rate data of each of the plurality of first unit grids. The following formula may be specifically used:

in the above formula, the first and second carbon atoms are,

may be a coarsening of the horizontal permeability and Q may be flow data of a horizontal equivalent percolation model determined from the flow data of the plurality of first meshes.

In an embodiment, the determining the coarsened vertical permeability according to the horizontal equivalent percolation model may specifically include the following. Reference may be made to fig. 4.

S15-4-2-1: and gridding the horizontal equivalent seepage model to obtain a plurality of first unit grids.

S15-4-2-2: and respectively calculating the center pressure of each first unit grid in the plurality of first grids.

S15-4-2-3: and determining the flow data of the vertical equivalent seepage model according to the central pressure of the first unit grids.

S15-4-2-4: and determining the coarsening vertical permeability according to the flow data of the vertical equivalent seepage model.

In this embodiment, the specific process of determining the coarsened vertical permeability is similar to the specific process of determining the coarsened horizontal permeability, and in the specific implementation, reference may be made to the process of determining the coarsened horizontal permeability, which is not described herein again.

In the embodiment of the application, compared with the prior art, by considering the seepage characteristics of the permeability in different directions in the reservoir, the preset pressure with unfixed numerical value is used as a boundary condition, the real reservoir seepage environments in different flowing directions are simulated by using an equivalent seepage method, and then the real coarsening horizontal permeability and the coarsening vertical permeability can be respectively determined. Therefore, the technical problems that the determined coarsening horizontal permeability and coarsening vertical permeability are inaccurate and low in reliability in the existing method are solved, and the technical effect that coarsening permeabilities in different directions can be accurately determined is achieved.

In one embodiment, in the case that the target well is a non-coring well, the core image of the target well cannot be directly obtained, and in order to determine the coarsened horizontal permeability and the coarsened vertical permeability in this case, the following may be performed.

S1: and determining the shale content according to the logging data.

S2: and determining a plurality of mud-sand content ratios by using the mud content.

S3: and establishing a plurality of second sand models according to the horizontal permeability of the sandstone, the vertical permeability of the sandstone and the content ratios of the plurality of sands.

S4: and determining the coarsening horizontal permeability and the coarsening vertical permeability by utilizing the plurality of second silt models through a sand body communication rate calculation formula based on statistics.

In the present embodiment, on the basis of the heterolite model with different sandstone contents (i.e. corresponding to a plurality of sand-sand content ratios), the specific influence of the shale interlayer in the formation where the target well is located on the permeability is considered, that is, the transverse spreading characteristic of the shale interlayer in the formation, and the influence on the vertical permeability is usually greater than the influence on the horizontal permeability. This is because the existence of the argillaceous interlayer can cause the difference of the horizontal and vertical connectivity of the sand body, and the difference of the horizontal permeability and the vertical permeability. In conjunction with a particular formation environment, for example, if the shale interlayer is altered by biological perturbation, it will likely result in increased vertical permeability. Therefore, to better determine coarsened horizontal permeability and coarsened vertical in the case of non-cored wellsPermeability, in specific implementation, a statistical relationship between the percent sandstone content and the horizontal permeability and the vertical permeability can be obtained through simulation based on a argillaceous interlayer model with different sand-sand content ratios (see fig. 7 for a schematic diagram of a correlation relationship between permeability and the argillaceous content obtained by applying the method/device for determining coarsening permeability provided by the embodiment of the present application), a fitting formula is established through nonlinear regression analysis of permeability and the percent sandstone content, that is, a sand body connectivity calculation formula based on statistics is used as a mathematical model for calculating the horizontal permeability and the vertical permeability, and specific coarsening horizontal permeability and coarsening vertical permeability are determined, wherein in specific implementation, the isotropy of sandstone and argillaceous in a stratum where a target well is located can be specified, and the permeability of sandstone can be set to 100 × 10^-3μ m²The permeability of the mud can be set to 0.01 × 10^-3μm²。

Referring to fig. 7, a schematic diagram of a correlation between permeability and shale content is obtained by applying the method/device for determining coarsening permeability provided by the embodiment of the present application, and according to a simulation data result, the obtained data can be analyzed, and on the premise that the stratigraphy of the rock formation or the dip angle of the shale interlayer is not large, the permeabilities in two horizontal directions of the horizontal permeability Kx and Ky are basically the same, and the reduction speed is slow along with the reduction of the sandstone content, and the permeability is rapidly reduced after the percentage content of the sandstone is reduced to 10%; while the vertical permeability decreases more rapidly as the percentage of sandstone decreases from 100% to 80%. In addition, from the comparison of the permeability simulation result and the results of several arithmetic mean values, the permeability in two horizontal directions of Kx and Ky is similar to the arithmetic mean value and is slightly smaller, the vertical permeability Kz is larger than the harmonic mean value, and the horizontal permeability and the vertical permeability are distributed on two sides of the geometric mean value. Therefore, the conventional arithmetic mean method can be used as a coarsening calculation method of the horizontal permeability, but the conventional mean value calculation method is not applicable to coarsening calculation of the vertical permeability, and the method provided by the application is more accurate in solving.

In the specific implementation, the following method can be used.

The horizontal permeability is obtained by fitting:

K_x＝101.2V_S-3.08

in the above formula, K_xMay be the component in the horizontal permeability on the x-axis, V_SThe sandstone percentage content can be, and the specific form can be decimal.

K_y＝100V_S-1.605

In the above formula, K_yMay be the component in the horizontal permeability on the y-axis, V_SThe sandstone percentage content can be, and the specific form can be decimal.

The fitting of the vertical permeability Kz is slightly and relatively complex, the study divides two-stage fitting treatment by taking the sandstone percentage content of 0.8 as a boundary, embodies that the sandstone connectivity taking the boundary is different from the influence of the sandstone percentage content, and needs to consider the extreme difference influence of the sand-mud permeability. In specific implementation, a vertical permeability calculation formula can be obtained by fitting:

at V_SIn the case of < 0.8,

at V_SIn the case that the temperature is more than or equal to 0.8,

and (3) carrying out normalization treatment, and taking the sand body communication rate as a weight coefficient to carry out weighted arithmetic average to finally obtain permeability values in all directions:

in the above formula, the first and second carbon atoms are,

may be the equivalent permeability of the coarsened grid in the x-direction,

may be the equivalent permeability, K, of the coarsened mesh in the y-direction_hmMay be the permeability of the argillaceous material in the horizontal direction, K_hsCan be the horizontal permeability of sand body, C_xCan be the sand body communication rate along the x direction, C_yMay be the sand connectivity in the y-direction.

At V_SIn the case of < 0.8,

in the above formula, the first and second carbon atoms are,

may be the equivalent permeability of the coarsened mesh in the z-direction, C_zThe sand connectivity in the z-direction may be used.

At V_SIn the case that the temperature is more than or equal to 0.8,

in the above formula, K_vsCan be the permeability of the sand body in the vertical direction, K_vmMay be the permeability of the shale in the vertical direction.

In one embodiment, the above calculation model may also be corrected to make the determined accuracy of coarsened vertical permeability relatively better, considering that the vertical permeability model itself is relatively complex to construct. Specifically, the following may be included.

(1) In order to ensure better transitivity between the model with the sandstone percentage content not less than 0.8 and the model with the sandstone percentage content less than 0.8, a first correction value of the high-sandstone percentage content model can be determined as follows:

in the above formula, the first and second carbon atoms are,

may be a first correction value, Cor₀The characteristic value, Cor, can be corrected for the first limit₁The characteristic value may be corrected for the second limit.

(2) Considering that the high sandstone percentage model has poor adaptability when the permeability of the sand mud is extremely poor, the second correction value of the high sandstone percentage model can be determined in the following manner:

and then the coarsening vertical permeability corresponding to different conditions can be more accurately determined according to the corrected model in the following way:

at V_SIn the case of < 0.8,

at V_SIn the case that the temperature is more than or equal to 0.8,

in the above formula, the first and second carbon atoms are,

it may be a first correction value or values,

it may be the second correction value that,

to coarsen the vertical permeability.

In one embodiment, after determining the coarsened horizontal permeability and the coarsened vertical permeability, the method may further specifically include the following for reservoir prediction and for guiding well site deployment.

S1: performing reservoir evaluation according to the coarsening horizontal permeability and the coarsening vertical permeability;

s2: and guiding well position deployment according to the reservoir evaluation result.

In this embodiment, it is to be added that, in the concrete implementation, the determined coarsening horizontal permeability and coarsening vertical permeability of the target well may be introduced into a specific numerical model, a simulation result is obtained through model operation, and the reservoir is specifically evaluated and predicted according to the simulation result.

From the above description, it can be seen that, according to the determination method for coarsening permeability provided by the embodiment of the application, by considering the seepage characteristics of the permeabilities in different directions in the reservoir, with the preset pressure with an unfixed numerical value as a boundary condition, the real reservoir seepage environments in different flowing directions are simulated by using an equivalent seepage method, and then the real coarsening horizontal permeability and the coarsening vertical permeability can be respectively determined. Therefore, the technical problems of inaccurate coarsening horizontal permeability and coarsening vertical permeability and low reliability in the existing method are solved, and the technical effect of accurately determining coarsening permeability in different directions is achieved; and establishing models corresponding to different flowing directions by combining the seepage characteristics of permeability in different directions according to the specific geological environment in the reservoir: the horizontal equivalent seepage model and the vertical equivalent seepage model are used for determining relatively accurate coarsened horizontal permeability and coarsened vertical permeability, so that the accuracy of the determined permeability is improved; and the corresponding permeability is determined by using an equivalent seepage method for the cored wells, and the permeability is solved for the non-cored wells according to a sand body communication rate calculation formula based on statistics, so that the permeability of the regions under different conditions can be determined more accurately.

Based on the same inventive concept, the embodiment of the present invention further provides a device for determining coarsening permeability, as described in the following embodiment. Because the principle of solving the problems by the device is similar to the determination method of the coarsening permeability, the implementation of the determination device of the coarsening permeability can be referred to the implementation of the determination method of the coarsening permeability, and repeated parts are not repeated again. As used hereinafter, the term "unit" or "module" may be a combination of software and/or hardware that implements a predetermined function. Although the means described in the embodiments below are preferably implemented in software, an implementation in hardware, or a combination of software and hardware is also possible and contemplated. Referring to fig. 8, a block diagram of an apparatus for determining rough permeability according to an embodiment of the present disclosure may include: the acquiring module 21, the first determining module 22, the second determining module 23, the third determining module 24, and the fourth determining module 25, and the structure thereof will be described in detail below.

The obtaining module 21 may be specifically configured to obtain core data and logging data of a target well, where the core data includes core plug sample data;

a first determining module 22, which may be specifically configured to determine a median value of sandstone particle sizes according to the logging data;

the second determining module 23 may be specifically configured to determine permeability of the sandstone according to the median of the sandstone particle size and the core plug sample data, where the permeability of the sandstone includes: horizontal permeability of sandstone, vertical permeability of sandstone;

a third determination module 24, which may be specifically configured to determine whether the target well is a cored well;

the fourth determining module 25 may be specifically configured to, when the target well is a core well, determine, according to the horizontal permeability of the sandstone and the vertical permeability of the sandstone, and using a preset pressure as a boundary condition, an equivalent percolation method to determine a coarsening permeability, where the coarsening permeability includes: coarsening horizontal permeability and coarsening vertical permeability.

In an embodiment, in order to determine the coarsening horizontal permeability and the coarsening vertical permeability respectively by using an equivalent percolation method according to the horizontal permeability of the sandstone and the vertical permeability of the sandstone with a preset pressure as a boundary condition when the target well is a core well, the fourth determining module 25 may specifically include the following structure:

the first obtaining unit is specifically used for obtaining a core image of the target well according to the core data;

the first determining unit may be specifically configured to grid the core image, and determine a configuration relationship between sandstone and mudstone in the target well according to the grid core image;

the first establishing unit is specifically configured to respectively establish a horizontal equivalent seepage model and a vertical equivalent seepage model according to the configuration relationship between the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone, and the vertical permeability of the sandstone, with the preset pressure as a boundary condition;

the second determining unit may be specifically configured to determine the coarsened horizontal permeability according to the horizontal equivalent seepage model, and determine the coarsened vertical permeability according to the vertical equivalent seepage model.

In one embodiment, in order to determine the coarsening horizontal permeability and the coarsening vertical permeability in the case of a non-cored well, the apparatus may further include a fifth determination module, where the fifth determination module may be specifically configured to determine the coarsening horizontal permeability and the coarsening vertical permeability according to the permeability of the sandstone and the log data in the case that the target well is the non-cored well.

In an embodiment, the fifth determining module may specifically include the following structure:

the third determining unit can be specifically used for determining the shale content according to the logging data;

a fourth determining unit, which can be specifically used for determining a plurality of content ratios of the silt by using the content of the silt;

the second establishing unit may be specifically configured to establish a plurality of second sand models according to the horizontal permeability of the sandstone, the vertical permeability of the sandstone, and the content ratios of the plurality of sands;

the fifth determining unit may be specifically configured to determine the coarsening horizontal permeability and the coarsening vertical permeability according to a sand body communication rate calculation formula based on statistics by using the plurality of second sand models.

In one embodiment, after determining the coarsened horizontal permeability and the coarsened vertical permeability, the device may further include the following structure in order to perform specific reservoir exploration and development on the target reservoir:

the evaluation module can be specifically used for evaluating the reservoir in the area where the target well is located according to the coarsening horizontal permeability and the coarsening vertical permeability;

the development module can be specifically used for guiding well position deployment according to the reservoir evaluation result.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the system embodiment, since it is substantially similar to the method embodiment, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

It should be noted that, the systems, devices, modules or units described in the above embodiments may be implemented by a computer chip or an entity, or implemented by a product with certain functions. For convenience of description, in the present specification, the above devices are described as being divided into various units by functions, and are described separately. Of course, the functionality of the units may be implemented in one or more software and/or hardware when implementing the present application.

Moreover, in the subject specification, adjectives such as first and second may only be used to distinguish one element or action from another element or action without necessarily requiring or implying any actual such relationship or order. References to an element or component or step (etc.) should not be construed as limited to only one of the element, component, or step, but rather to one or more of the element, component, or step, etc., where the context permits.

From the above description, it can be seen that the determination apparatus for coarsening permeability provided in the embodiment of the present application, by considering the specific anisotropic seepage characteristics of the reservoir permeability, uses the pressure with an unfixed value as a boundary condition through the fourth determination module, and uses an equivalent seepage method to respectively simulate the real reservoir seepage environment, so as to respectively determine the coarsening horizontal permeability and the coarsening vertical permeability, thereby solving the technical problems of inaccurate and low reliability of the determined coarsening horizontal permeability and coarsening vertical permeability in the existing method, and achieving the technical effect of accurately determining coarsening permeability in different directions; the first establishing unit is used for establishing a corresponding horizontal equivalent seepage model and a vertical equivalent seepage model according to the specific environment in the reservoir and by combining the seepage characteristics of the permeability in different directions, so that the more accurate coarsened horizontal permeability and coarsened vertical permeability are determined, and the accuracy of the determined permeability is improved; and the permeability of the non-coring well is solved through the fifth determination module according to a sand body communication rate calculation formula based on statistics, so that the permeability of the regions under different conditions can be determined more accurately.

In a specific implementation scenario, the coarsening horizontal permeability and the coarsening vertical permeability of the region are specifically evaluated by using the determination method/device for coarsening permeability provided by the application. The specific implementation process can be combined with the flow chart of the determination method/apparatus for coarsening permeability provided by the embodiment of the present application shown in fig. 9, see the following.

S1: according to the core data, for the core well, the shale characteristic recognition of the core image and the calculation of the configuration relation of mudstone and sandstone are utilized; calculating the shale content of the non-coring well according to the GR logging curve;

s2: determining a median sandstone granularity value according to a GR logging curve in logging data;

s3: the horizontal permeability of the pure sandstone is obtained through a relation model of the sandstone median particle size and the horizontal permeability of the core plug, and the vertical permeability of the pure sand is obtained according to the relation model of the vertical permeability and the horizontal permeability of the core plug;

s4: for the core well, according to the configuration relation of sandstone and mudstone, based on the two-dimensional gridding of a core image, carrying out coarsening calculation on the horizontal and vertical permeabilities of the single well of the core well by adopting a permeability anisotropy calculation method of equivalent seepage, so as to obtain coarsened horizontal permeability and coarsened vertical permeability; and for the non-coring well, coarsening calculation of horizontal permeability and vertical permeability is respectively carried out by utilizing a sand body connectivity mathematical calculation model based on statistics, so as to obtain corresponding coarsening horizontal permeability and coarsening vertical permeability.

Through the above-mentioned scene example, it is verified that the determination method and apparatus for coarsening permeability provided by the embodiment of the present application take account of the specific anisotropic seepage characteristics of the reservoir permeability, are different from setting a fixed boundary condition, but use the pressure with an unfixed value as a specific boundary condition, and utilize the equivalent seepage method to respectively simulate the real reservoir seepage environment, so as to respectively determine the horizontal permeability and the vertical permeability, thereby indeed solving the technical problems of inaccurate horizontal permeability and vertical permeability and low reliability in the existing method, and achieving the technical effect of accurately determining the permeabilities in different directions

Although various specific embodiments are mentioned in the present application, the present application is not limited to the cases described in the industry standards or examples, and the like, and some industry standards or the embodiments slightly modified based on the implementation described in the custom manner or examples can also achieve the same, equivalent or similar implementation effects as those of the above embodiments or the implementation effects expected after the modifications. Embodiments employing such modified or transformed data acquisition, processing, output, determination, etc., may still fall within the scope of alternative embodiments of the present application.

Although the present application provides method steps as described in an embodiment or flowchart, more or fewer steps may be included based on conventional or non-inventive means. The order of steps recited in the embodiments is merely one manner of performing the steps in a multitude of orders and does not represent the only order of execution. When an apparatus or client product in practice executes, it may execute sequentially or in parallel (e.g., in a parallel processor or multithreaded processing environment, or even in a distributed data processing environment) according to the embodiments or methods shown in the figures. The terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, the presence of additional identical or equivalent elements in a process, method, article, or apparatus that comprises the recited elements is not excluded.

The devices or modules and the like explained in the above embodiments may be specifically implemented by a computer chip or an entity, or implemented by a product with certain functions. For convenience of description, the above devices are described as being divided into various modules by functions, and are described separately. Of course, in implementing the present application, the functions of each module may be implemented in one or more pieces of software and/or hardware, or a module that implements the same function may be implemented by a combination of a plurality of sub-modules, and the like. The above-described apparatus embodiments are merely illustrative, and for example, the division of the modules is merely a logical division, and other divisions may be realized in practice, for example, a plurality of modules or components may be combined or integrated into another system, or some features may be omitted, or not executed.

Those skilled in the art will also appreciate that, in addition to implementing the controller as pure computer readable program code, the same functionality can be implemented by logically programming method steps such that the controller is in the form of logic gates, switches, application specific integrated circuits, programmable logic controllers, embedded microcontrollers and the like. Such a controller may therefore be considered as a hardware component, and the means included therein for performing the various functions may also be considered as a structure within the hardware component. Or even means for performing the functions may be regarded as being both a software module for performing the method and a structure within a hardware component.

The application may be described in the general context of computer-executable instructions, such as program modules, being executed by a computer. Generally, program modules include routines, programs, objects, components, data structures, classes, etc. that perform particular tasks or implement particular abstract data types. The application may also be practiced in distributed computing environments where tasks are performed by remote processing devices that are linked through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including memory storage devices.

From the above description of the embodiments, it is clear to those skilled in the art that the present application can be implemented by software plus necessary general hardware platform. Based on such understanding, the technical solutions of the present application may be embodied in the form of a software product, which may be stored in a storage medium, such as a ROM/RAM, a magnetic disk, an optical disk, or the like, and includes several instructions for enabling a computer device (which may be a personal computer, a mobile terminal, a server, or a network device) to execute the method according to the embodiments or some parts of the embodiments of the present application.

The embodiments in the present specification are described in a progressive manner, and the same or similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. The application is operational with numerous general purpose or special purpose computing system environments or configurations. For example: personal computers, server computers, hand-held or portable devices, tablet-type devices, multiprocessor systems, microprocessor-based systems, set top boxes, programmable electronic devices, network PCs, minicomputers, mainframe computers, distributed computing environments that include any of the above systems or devices, and the like.

While the present application has been described by way of examples, those of ordinary skill in the art will appreciate that there are numerous variations and permutations of the present application that do not depart from the spirit of the present application and that the appended embodiments are intended to include such variations and permutations without departing from the present application.

Claims

1. A method for determining coarsening permeability, comprising:

determining whether the target well is a cored well;

under the condition that the target well is a coring well, determining coarsening permeability by using an equivalent seepage method according to the permeability of the sandstone and by taking preset pressure as a boundary condition, wherein the coarsening permeability comprises the following steps: coarsening the horizontal permeability and coarsening the vertical permeability;

determining the permeability of the sandstone according to the median of the sandstone particle size and the core plug sample data, wherein the determining comprises: determining the horizontal permeability of the sandstone according to the median of the sandstone particle size and the core plug sample data; and determining the vertical permeability of the sandstone according to the horizontal permeability of the sandstone and the data of the core plug sample.

2. The method of claim 1, wherein determining the coarsening permeability according to the permeability of the sandstone with a preset pressure as a boundary condition by using an equivalent percolation method comprises:

3. The method of claim 2, wherein the establishing a horizontal equivalent seepage model and a vertical equivalent seepage model respectively according to the configuration relationship of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone and the vertical permeability of the sandstone with the preset pressure as a boundary condition comprises:

4. The method of claim 3, wherein determining the coarsened horizontal permeability according to the horizontal equivalent percolation model comprises:

respectively calculating the central pressure of the first unit grid;

5. The method of claim 2, wherein the establishing of the vertical equivalent seepage model according to the configuration relationship of the sandstone and the mudstone in the target well, the horizontal permeability of the sandstone, and the vertical permeability of the sandstone with the preset pressure as a boundary condition comprises:

6. The method of claim 5, wherein determining the coarsened vertical permeability according to the vertical equivalent percolation model comprises:

respectively calculating the central pressure of the second unit grid;

7. The method of claim 1, wherein in the case where the target well is a non-cored well, the method comprises:

determining the shale content according to the logging data;

determining a plurality of mud-sand content ratios by using the mud content;

8. The method of claim 1, wherein after determining the coarsening permeability, the method comprises:

according to the coarsening permeability, evaluating the reservoir stratum;

9. An apparatus for determining coarsening permeability, comprising:

a fourth determining module, configured to determine, according to the permeability of the sandstone and using a preset pressure as a boundary condition, an coarsening permeability by using an equivalent seepage method when the target well is a core well, where the coarsening permeability includes: coarsening horizontal permeability and coarsening vertical permeability;

the second determining module is specifically configured to determine the horizontal permeability of the sandstone according to the median of the sandstone particle size and the core plug sample data; and determining the vertical permeability of the sandstone according to the horizontal permeability of the sandstone and the data of the core plug sample.

10. The apparatus of claim 9, wherein the fourth determining module comprises:

11. The apparatus of claim 9, further comprising a fifth determination module for determining the coarsened horizontal permeability and the coarsened vertical permeability from the permeability of the sandstone and the logging data if the target well is a non-cored well, wherein the fifth determination module comprises: