Inter-well Seepage Channel Characterization Method, Device and Storage Medium Based on Water Flooding

Abstract

An embodiment of this specification provides a method, device, and storage medium for characterizing inter-well seepage channels based on water flooding, which are applied to the technical field of reservoir development. The method includes: obtaining geological parameters of a target reservoir; calculating equivalent fracture seepage parameters and matrix seepage parameters in the target reservoir based on the geological parameters; the equivalent fractures are formed by connecting horizontal fractures and the matrix in the target reservoir in series; the equivalent fractures in the target reservoir constitute the inter-well seepage channels; determining a water cut calculation model according to the equivalent fracture seepage parameters and matrix seepage parameters; obtaining a water cut change curve during the water flooding process based on the water flooding process parameters; and inversely analyzing the inter-well seepage channels through the water cut change curve during the water flooding process. The above method realizes the calculation of the corresponding parameters of the inter-well seepage channels, effectively realizes the quantitative characterization of the inter-well seepage channels, and can thus guide the actual reservoir development, which is beneficial to the effective progress of production and development.

Description

Technical Field

[0001] The embodiments of this specification relate to the technical field of reservoir development, and particularly to a method, device, and storage medium for characterizing inter-well seepage channels based on water flooding. Background Art

[0002] Inter-well displacement is an effective way to develop an oil reservoir. By injecting a displacement fluid between injection and production wells, the oil reservoir between the injection and production wells can be discharged through the inter-well seepage channel under the displacement effect of the displacement fluid, thereby effectively completing the oil reservoir recovery.

[0003] Currently, when developing an oil reservoir, especially a fractured-vuggy carbonate rock oil reservoir, due to the development of dominant channels inside the reservoir, serious water channeling occurs, the injected water has low or ineffective circulation, and the utilization rate of the injected water is low. When using the method of combining profile control and water shutoff for construction, the expected effect is often not achieved. The fundamental reason lies in the insufficient understanding of the inter-well seepage channel. In the case where the study of the inter-well seepage channel plays a great role in improving the oil recovery rate of the oil reservoir by water flooding, the inability to effectively characterize the inter-well seepage channel of the oil reservoir will inevitably affect the normal progress of production and development. Therefore, there is an urgent need for a method to effectively quantify and characterize the seepage channel during the inter-well water flooding process. Summary of the Invention

[0004] The purpose of the embodiments of this specification is to provide a method, device, and storage medium for characterizing inter-well seepage channels based on water flooding to solve the problem of how to effectively quantify and characterize the seepage channel during the inter-well water flooding process.

[0005] To solve the above technical problems, the embodiments of this specification propose a method for characterizing inter-well seepage channels based on water flooding, including: obtaining the geological parameters of the target oil reservoir; calculating the equivalent fracture seepage parameters and matrix seepage parameters in the target oil reservoir based on the geological parameters; the equivalent fracture is formed by connecting horizontal fractures and the matrix in the target oil reservoir in series; the equivalent fractures in the target oil reservoir constitute the inter-well seepage channel; determining a water cut calculation model based on the equivalent fracture seepage parameters and matrix seepage parameters; obtaining the water cut change curve during the water flooding process based on the water flooding process parameters; and inversely analyzing the inter-well seepage channel through the water cut change curve during the water flooding process.

[0006] An embodiment of this specification also provides an inter-well seepage channel characterization device based on water flooding, including: a geological parameter acquisition module for acquiring geological parameters of a target oil reservoir; a parameter calculation module for calculating equivalent fracture seepage parameters and matrix seepage parameters in the target oil reservoir based on the geological parameters; the equivalent fracture is formed by connecting horizontal fractures and the matrix in series in the target oil reservoir; the equivalent fractures in the target oil reservoir constitute the inter-well seepage channel; a water cut calculation model determination module for determining a water cut calculation model according to the equivalent fracture seepage parameters and matrix seepage parameters; a water cut change curve acquisition module for acquiring a water cut change curve during the water flooding process based on water flooding process parameters; an inter-well seepage channel inversion module for inverting the inter-well seepage channel through the water cut change curve during the water flooding process.

[0007] An embodiment of this specification also provides a computer storage medium, on which a computer program / instructions are stored, and when the computer program / instructions are executed, the above-mentioned method for characterizing an inter-well seepage channel based on water flooding is implemented.

[0008] As can be seen from the technical solutions provided by the embodiments of this specification above, in view of the characteristics of the target oil reservoir, the embodiments of this specification divide it into equivalent fractures formed by connecting horizontal fractures and the matrix in series and the matrix other than the equivalent fractures, and then calculate the equivalent fracture seepage parameters and matrix seepage parameters of the target oil reservoir respectively based on the geological parameters of the target oil reservoir to characterize the seepage characteristics of different regions in the target oil reservoir. Then, according to the calculated equivalent fracture seepage parameters and matrix seepage parameters, and combined with the characteristics of the water flooding process, the water cut change curve during the water flooding process is determined, and then the inter-well seepage channel is inverted based on the water cut change curve during the water flooding process. Through the above implementation manner, the calculation of the corresponding parameters of the inter-well seepage channel is realized, the quantitative characterization of the inter-well seepage channel is effectively realized, and then the actual oil reservoir development can be guided, which is beneficial to the effective progress of production development. Description of the Drawings

[0009] In order to more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in this specification. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0010] Figure 1 It is a flowchart of a method for characterizing an inter-well seepage channel based on water flooding according to an embodiment of this specification;

[0011] Figure 2A It is a schematic diagram of a water cut transformation curve according to an embodiment of this specification;

[0012] Figure 2BSchematic diagram of a moisture content transformation curve according to an embodiment of this specification;

[0013] Figure 2C Schematic diagram of a moisture content transformation curve according to an embodiment of this specification;

[0014] Figure 2D Schematic diagram of a moisture content transformation curve according to an embodiment of this specification;

[0015] Figure 2E Schematic diagram of a moisture content transformation curve according to an embodiment of this specification;

[0016] Figure 2F Schematic diagram of a moisture content transformation curve according to an embodiment of this specification;

[0017] Figure 2G Schematic diagram of a moisture content transformation curve according to an embodiment of this specification;

[0018] Figure 2H Schematic diagram of a moisture content transformation curve according to an embodiment of this specification;

[0019] Figure 2I Schematic diagram of a moisture content transformation curve according to an embodiment of this specification;

[0020] Figure 2J Schematic diagram of a moisture content transformation curve according to an embodiment of this specification;

[0021] Figure 3 Module diagram of an inter - well seepage channel characterization device based on water flooding according to an embodiment of this specification. Specific implementation manners

[0022] Next, the technical solutions in the embodiments of this specification will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of this specification. Obviously, the described embodiments are only a part of the embodiments of this specification, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this specification without creative efforts shall fall within the scope of protection of this specification.

[0023] To solve the above - mentioned technical problems, an embodiment of this specification proposes an inter - well seepage channel characterization method based on water flooding. The execution subject of the inter - well seepage channel characterization method based on water flooding can be an inter - well seepage channel characterization device based on water flooding, and the inter - well seepage channel characterization device based on water flooding includes, but is not limited to, servers, industrial control computers, PC machines, etc. As Figure 1 shown, the inter - well seepage channel characterization method based on water flooding may include the following specific implementation steps.

[0024] S110: Obtain the geological parameters of the target oil reservoir.

[0025] The target reservoir is the reservoir targeted for the characterization of the inter-well seepage channels this time, that is, it can correspond to the work area developed this time. There are inter-well seepage channels in the formation of the target reservoir, which serve as the channels for the displacement fluid and oil to flow during the displacement process. The inter-well seepage channels can be a network or multi-layer structure formed by different fractures.

[0026] In some embodiments, the target reservoir is a fractured-vuggy carbonate reservoir. Due to the development of dominant channels inside the fractured-vuggy carbonate reservoir, serious water channeling occurs, the injected water has inefficient or ineffective circulation, and the utilization rate of the injected water is relatively low, which is more in line with the utilization environment of this application.

[0027] Geological parameters can be relevant parameters collected or detected for the formation of the target reservoir, and then subsequent calculations for specific parameter values can be achieved. Specifically, in the embodiments of this specification, the geological parameters can include matrix permeability, horizontal fracture length ratio, equivalent fracture aperture, effective reservoir thickness, fracture dip angle, number of horizontal fracture layers, fracture-cavity volume coefficient, total area of seepage interface, width ratio of fractures in the seepage cross-section, etc. In practical applications, other parameters can be set as geological parameters according to requirements, which are not limited to the above examples and are not restricted in this regard.

[0028] In some embodiments, the target reservoir satisfies the following conditions: there is an equivalent fracture formed by the series connection of horizontal fractures and matrix between wells, and the widths of the horizontal fractures and matrix connected in series in the equivalent fracture are equal, and outside the equivalent fracture is pure matrix, and / or, the water flooding process is equivalent to piston displacement, and / or, the apertures of different equivalent fractures are different, and the apertures of all equivalent fractures follow a lognormal distribution.

[0029] In addition, for the convenience of calculation, the following assumed conditions can also be added: in the seepage cross-section, the width ratio of the equivalent fracture is P, and the width ratio of the matrix is 1 - P, and / or, along the seepage direction, the length ratio of the horizontal fracture is R.

[0030] S120: Calculate the equivalent fracture seepage parameters and matrix seepage parameters in the target reservoir based on the geological parameters; the equivalent fracture is formed by the series connection of horizontal fractures and matrix in the target reservoir; the equivalent fractures in the target reservoir constitute the inter-well seepage channels.

[0031] The equivalent fracture can be a fracture formed by the series connection of horizontal fractures and matrix. In practical applications, it may not be the case that all fractures are directly connected to the injection and production wells. During the displacement process, the displacement fluid can flow based on the horizontal fractures and the corresponding matrix, which can also ensure the effective progress of the displacement process. The equivalent fracture is the fracture formed by the series connection of horizontal fractures and matrix. The inter-well seepage channels are constituted by the equivalent fractures, and the flow of the displacement fluid between wells is achieved through the network or layered structure formed by different equivalent fractures.

[0032] The equivalent fracture seepage parameters and matrix seepage parameters are respectively used to characterize the flow characteristics of the liquid in the equivalent fracture and the matrix, so as to better characterize the flow characteristics of the oil and displacement fluid during the displacement process. In some embodiments, the equivalent fracture seepage parameters include the equivalent fracture water production and the equivalent fracture oil production; the matrix seepage parameters include the matrix water production and the matrix oil production.

[0033] The equivalent fracture water production is used to represent the content of the water produced based on the equivalent fracture, and the equivalent fracture liquid production includes the total amount of the produced water and oil. Correspondingly, the matrix water production is used to represent the content of the water produced based on the matrix, and the equivalent fracture liquid production includes the total amount of the produced water and oil.

[0034] In some embodiments, the process of calculating the equivalent fracture seepage parameters and the matrix seepage parameters may be to first calculate the equivalent fracture permeability based on the geological parameters, then calculate the equivalent fracture seepage velocity using the equivalent fracture permeability, and calculate the matrix seepage velocity using the matrix permeability. Then, the equivalent fracture water production and the equivalent fracture liquid production are determined according to the equivalent fracture seepage velocity, and the matrix water production and the matrix liquid production are determined according to the matrix seepage velocity.

[0035] Generally, for a single horizontal fracture without a matrix, the permeability of the fracture considering roughness and tortuosity can be expressed as In the formula, K f1 is the permeability of a single horizontal fracture, μm 2 ; b is the aperture of a single horizontal fracture, μm 2 ; c1 is the influence coefficient of roughness and tortuosity on the fracture permeability, taking 0.75.

[0036] Combining the above formula, for the equivalent fracture formed by the series connection of the horizontal fracture and the matrix, according to the principle of equal pressure drop, the relationship corresponding to the equivalent fracture permeability can be derived as Converted into the formula In the formula, K f is the permeability of a single equivalent fracture, μm 2 ; b is the aperture of a single equivalent fracture, μm 2 ; R is the proportion of the length of the horizontal fracture in the seepage direction, taking 0.9 according to the fracture model in the work area; K m is the matrix permeability, μm 2 ; h is the effective thickness of the reservoir, cm. After trial calculation, the gap between K f and K f1 is mainly affected by R, and the multiple within 100 μm is approximately R.

[0037] Therefore, combining the aforementioned formula for the permeability of a single horizontal fracture, the equivalent fracture permeability can be expressed as Wherein, c is the influence coefficient of roughness and tortuosity on the fracture permeability, c = c1R, and in this work area, it is taken as 0.75×0.9 = 0.675.

[0038] Subsequently, combining Darcy's law and the cubic law, the seepage motion equation in the fracture is derived, and we can obtain Wherein, v f is the inter-well injection water channeling velocity, cm / s; K f is the permeability of a single equivalent fracture, μm 2 ; μ is the viscosity of the injection water, mPa·s; △p is the injection-production pressure difference, bar; L is the injection-production well spacing, cm; ρ is the density of the mixed fluid, kg / m 3 ; g is the acceleration of gravity, N / kg; α is the fracture dip angle.

[0039] Correspondingly, the seepage motion equation in the matrix can be Wherein, v m is the inter-well injection water seepage velocity, cm / s.

[0040] In addition, there is a relational expression for the injection-production pressure difference The injection-production pressure difference can be substituted for specific solution.

[0041] After obtaining the seepage parameters in the equivalent fracture and the matrix respectively, the water production, liquid production of the fracture and the water production, liquid production of the matrix can be calculated.

[0042] Specifically, the formula can be used to calculate the water production of the equivalent fracture. In the formula, Q fw is the water production of the equivalent fracture, cm 3 / s; n is the number of horizontal fracture layers, which can be determined according to the fracture line density and the thickness h; m is the fracture-cavity volume coefficient, which represents the volume increase multiple brought by the distributed holes in the inter-well fracture; W is the total width of the seepage cross-section, P is the proportion of the width occupied by the fracture in the seepage cross-section, b max is the maximum opening of the fracture occupied by the injection water, b(t) is the opening of the fracture occupied by the injection water at time t, and f(b) is the probability density function of the average total opening b of the fracture, which follows a lognormal distribution with a cumulative probability of 1 within (0, b max .

[0043] The formula is used to calculate the liquid production of the equivalent fracture. In the formula, Q f is the liquid production of the equivalent fracture, cm 3 / s.

[0044] The formula is used to calculate the water production of the matrix. In the formula, Q mw is the water production of the matrix, cm 3 / s, where h is the reservoir thickness, in cm; φ is the reservoir porosity, and f w0 is the initial water saturation of the reservoir.

[0045] The formula is used to calculate the matrix liquid production rate. In the formula, Q m is the matrix liquid production rate, in cm 3 / s.

[0046] In the above formula, according to Darcy's law and the cubic law, and can be obtained respectively. In the formula, t is the water injection time, t = 0 is the starting moment of water injection; t1 is the moment when the water cut of the production well starts to rise.

[0047] The apertures of horizontal fractures all follow a lognormal distribution. In an actual reservoir, the fracture aperture has a minimum value of 0 and a maximum value of b max , that is, the cumulative probability within (0, b max is 1. Therefore, by improving the lognormal distribution density function, the probability density function of the binary tree fracture aperture can be obtained, which can be specifically expressed as is the logarithmic mean of the fracture, σ is the logarithmic standard deviation of the fracture aperture, σ ∈ (0, +∞).

[0048] S130: Determine the water cut calculation model according to the equivalent fracture seepage parameters and matrix seepage parameters.

[0049] After calculating the equivalent fracture seepage parameters and matrix seepage parameters, the water cut calculation model can be determined. The water cut calculation model is used to determine the water cut in the target reservoir by comprehensively considering the water production and liquid production in the equivalent fracture and matrix.

[0050] The water cut calculation model can be characterized as That is, the ratio of the sum of water production to the sum of liquid production.

[0051] S140: Obtain the water cut change curve of the water flooding process based on the water flooding process parameters.

[0052] Based on the water flooding process, the corresponding water cut change curve of the water flooding process can be determined. In some embodiments, the water cut calculation model can be first transformed into a water flooding water cut calculation model based on the water flooding process to adapt to the actual production and development scenario.

[0053] Specifically, let The above formula can be characterized as

[0054] Combining the water flooding process to further simplify the above formula. First, let Then

[0055] Because Equation 1 can be written in the form of an expression containing the complementary error function

[0056] In the further transformation process, let y = lnb, then correspondingly, we can obtain e y = b, so

[0057] Let again Then Equation 3 can be changed to

[0058] Also because y = lnb, then

[0059] Let again Then the above Equations 5, 6, and 7 can be further transformed into

[0060] Based on the definition formula of the complementary error function, we can further obtain

[0061]

[0062] Combining the above Equations 2, 4, 11, 12, and 13, substituting them into the aforementioned water cut expression, the analytical solution of the theoretical water cut during the water flooding process can be formed as In the formula

[0063] After obtaining the above water flooding water cut calculation model, the production parameters corresponding to the target reservoir can be substituted into the water flooding water cut calculation model to obtain the water cut values at different times in the target reservoir, and then based on the water cut values, the water cut change curve during the water flooding process can be fitted. That is, the water cut change situation in the target reservoir is characterized by the water cut change curve

[0064] Such as Figures 2A to 2J shown, it is a water cut fitting schematic diagram for different water flooding stages. Among them Figure 2A is the water cut fitting result in the direction from Well A to Well B; Figure 2B is the water cut fitting result in the direction from Well A to Well C; Figure 2C is the water cut fitting result in the direction from Well D to Well E; Figure 2D is the water cut fitting result in the direction from Well D to Well C; Figure 2E is the water cut fitting result in the direction from Well A to Well F;Figure 2F is the fitting result of water cut in the direction from well G to well H; Figure 2G is the fitting result of water cut in the direction from well G to well E; Figure 2H is the fitting result of water cut in the direction from well I to well E; Figure 2I is the fitting result of water cut in the direction from well I to well C; Figure 2J is the fitting result of water cut in the direction from well J to well E. From the display effect of the above figures, it can be seen that the above method can effectively obtain the water cut at different times and effectively fit the water cut to obtain the final water cut change curve.

[0065] S150: Invert the inter-well seepage channel through the water cut change curve during the water flooding process.

[0066] After obtaining the water cut change curve, the change of water cut can be analyzed, and then the characteristics of the inter-well seepage channel can be determined in combination with the characteristics of the water cut change curve to realize the inversion of the inter-well seepage channel.

[0067] In some embodiments, the equivalent fracture characteristic parameters can be determined based on the water cut change curve during the water flooding process. Among them, the equivalent fracture characteristic parameters include at least one of the permeability ratio of a single equivalent fracture, the thickness of the equivalent inter-well channel, and the variance of the equivalent fracture aperture.

[0068] As shown in Table 1 below, the equivalent fracture characteristic parameters corresponding to different wells and determined based on different water inflow directions are shown. Through these equivalent fracture characteristic parameters, the characteristics of the inter-well seepage channel can be effectively analyzed and determined.

[0069] Table 1

[0070]

[0071]

[0072] By classifying the equivalent fracture characteristic parameters, they can be divided into three categories: small equivalent thickness and large ratio, medium ratio and small variance, and large equivalent thickness and medium to large ratio. Among them, in the category of small equivalent thickness and large ratio, the fracture aperture variance ≥ 0.5 and the equivalent thickness ≤ 10 mm, the connectivity of the inter-well fractures is good, there may be large-scale fractures, the volume of the inter-well channel is small, and the ratio is large. In the category of medium ratio and small variance, the fracture aperture variance < 0.5, the connectivity of the inter-well fractures is poor, and the overall performance is a small ratio. In the category of large equivalent thickness and medium to large ratio, the fracture aperture variance ≥ 0.5 and the equivalent thickness > 10 mm, the connectivity of the inter-well fractures is good, the volume of the inter-well channel is large, and the ratio is medium to large.

[0073] Through the introduction of the above embodiments and examples, it can be seen that the method divides the target reservoir according to its characteristics into an equivalent fracture formed by the series connection of horizontal fractures and matrix, and the matrix other than the equivalent fracture. Then, based on the geological parameters of the target reservoir, the equivalent fracture seepage parameters and matrix seepage parameters of the target reservoir are calculated respectively, which are used to characterize the seepage characteristics of different regions in the target reservoir. After that, according to the calculated equivalent fracture seepage parameters and matrix seepage parameters, and combined with the characteristics of the water flooding process, the water cut change curve of the water flooding process is determined, and then the inter-well seepage channel is inverted based on the water cut change curve of the water flooding process. Through the above implementation method, the calculation of the corresponding parameters of the inter-well seepage channel is realized, and the quantitative characterization of the inter-well seepage channel is effectively realized. Furthermore, it can guide the actual reservoir development and is beneficial to the effective progress of production development.

[0074] Based on the above-described method for characterizing the inter-well seepage channel based on water flooding, an embodiment of this specification also proposes a device for characterizing the inter-well seepage channel based on water flooding. The device for characterizing the inter-well seepage channel based on water flooding can be set in the device for characterizing the inter-well seepage channel based on water flooding. As Figure 3 shown, the device for characterizing the inter-well seepage channel based on water flooding may include the following modules.

[0075] The geological parameter acquisition module 310 is configured to acquire the geological parameters of the target reservoir.

[0076] The parameter calculation module 320 is configured to calculate the equivalent fracture seepage parameters and matrix seepage parameters in the target reservoir based on the geological parameters; the equivalent fracture is formed by the series connection of horizontal fractures and matrix in the target reservoir; the equivalent fractures in the target reservoir constitute the inter-well seepage channel.

[0077] The water cut calculation model determination module 330 is configured to determine the water cut calculation model according to the equivalent fracture seepage parameters and matrix seepage parameters.

[0078] The water cut change curve acquisition module 340 is configured to acquire the water cut change curve of the water flooding process based on the water flooding process parameters.

[0079] The inter-well seepage channel inversion module 350 is configured to invert the inter-well seepage channel through the water cut change curve of the water flooding process.

[0080] Based on Figure 1 the corresponding method for characterizing the inter-well seepage channel based on water flooding, an embodiment of this specification provides a computer-readable storage medium, on which a computer program / instructions are stored. The computer-readable storage medium can be read by a processor based on the internal bus of the device, and then the program instructions in the computer-readable storage medium are implemented through the processor.

[0081] In this embodiment, the computer-readable storage medium can be implemented in any suitable manner. The computer-readable storage medium includes, but is not limited to, Random Access Memory (RAM), Read-Only Memory (ROM), Cache, Hard Disk Drive (HDD), Memory Card, and so on. The computer storage medium stores computer program instructions. When the computer program instructions are executed, the program instructions or modules corresponding to the embodiments described in this specification are implemented. Figure 1 The program instructions or modules corresponding to the corresponding embodiments are implemented.

[0082] In this embodiment, the processor can be implemented in any suitable manner. For example, the processor can take the form of, for example, a microprocessor or a processor and a computer-readable medium storing computer-readable program code (such as software or firmware) executable by the (micro)processor, logic gates, switches, Application Specific Integrated Circuit (ASIC), programmable logic controller, and embedded microcontroller, and so on. Specifically, when the processor is set on the inter-well seepage channel characterization device based on water drive, it can execute Figure 1 The method steps in the corresponding embodiments.

[0083] The inter-well seepage channel characterization method, device, and storage medium in the embodiments of this specification can be applied to the field of reservoir development technology, and can also be applied to other technical fields outside the field of reservoir development technology, and no limitation is imposed thereon.

[0084] Although the process flow described above includes a plurality of operations that appear in a specific order, it should be clearly understood that these processes can include more or fewer operations, and these operations can be executed sequentially or in parallel (for example, using a parallel processor or a multi-threaded environment).

[0085] This application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of this specification. It should be understood that each flow and / or block in the flowcharts and / or block diagrams, and the combination of flows and / or blocks in the flowcharts and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, such that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the functions specified in Figure 1 One or more of the processes or a plurality of processes and / or blocks Figure 1 One or more of the blocks or a plurality of blocks.

[0086] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including an instruction means which implements the functions specified in one or more of the processes and / or blocks Figure 1 of one or more of the processes and / or blocks Figure 1 specified in the flowchart.

[0087] These computer program instructions can also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, whereby the instructions executed on the computer or other programmable apparatus provide steps for implementing the functions specified in one or more of the processes and / or blocks Figure 1 of one or more of the processes and / or blocks Figure 1 specified in the flowchart.

[0088] Those skilled in the art will appreciate that the embodiments of the present specification may be provided as a method, system, or computer program product. Accordingly, the embodiments of the present specification may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Moreover, the embodiments of the present specification may take the form of a computer program product implemented on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0089] The embodiments of the present specification may be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc. that perform particular tasks or implement particular abstract data types. The embodiments of the present specification may also be practiced in a distributed computing environment where tasks are performed by remote processing devices connected through a communications network. In a distributed computing environment, program modules may be located in both local and remote computer storage media including storage devices.

[0090] Each embodiment in this specification is described in a progressive manner. For the same or similar parts among the embodiments, reference can be made to each other. Each embodiment focuses on the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple. For the relevant parts, reference can be made to the corresponding description in the method embodiment. In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of this specification. In this specification, the schematic expression of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0091] The above description is only for the embodiments of the present application and is not intended to limit the present application. For those skilled in the art, various changes and modifications can be made to the present application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the scope of the claims of the present application.

Claims

1. A method for characterizing inter-well seepage channels based on water flooding, characterized in that, Including: Obtaining geological parameters of a target reservoir; Calculating equivalent fracture seepage parameters and matrix seepage parameters in the target reservoir based on the geological parameters; The equivalent fracture is formed by connecting horizontal fractures and matrix in series in the target reservoir; the equivalent fractures in the target reservoir constitute the inter-well seepage channel; Determining a water cut calculation model according to the equivalent fracture seepage parameters and matrix seepage parameters; Obtaining the water cut change curve of the water flooding process based on the water flooding process parameters; Inverting the inter-well seepage channel through the water cut change curve of the water flooding process; Wherein, the equivalent fracture seepage parameters include equivalent fracture water production and equivalent fracture liquid production; the matrix seepage parameters include matrix water production and matrix liquid production; calculating the equivalent fracture seepage parameters and matrix seepage parameters in the target reservoir based on the geological parameters includes: calculating the equivalent fracture permeability based on the geological parameters; calculating the equivalent fracture seepage velocity using the equivalent fracture permeability; calculating the matrix seepage velocity using the matrix permeability; determining the equivalent fracture water production and equivalent fracture liquid production according to the equivalent fracture seepage velocity; determining the matrix water production and matrix liquid production according to the matrix seepage velocity; The equivalent fracture seepage parameters include at least one of equivalent fracture water production, equivalent fracture oil production, matrix water production, and matrix oil production; the water cut calculation model is where f w is the water cut, Q fw is the equivalent fracture water production, Q f is the equivalent fracture liquid production, Q mw is the matrix water production, Q m is the matrix liquid production.

2. The method according to claim 1, characterized in that, The target reservoir includes a fractured-vuggy carbonate reservoir.

3. The method according to claim 1, characterized in that, Calculating the equivalent fracture permeability based on the geological parameters includes: Using the formula to calculate the equivalent fracture permeability, where K f is the single equivalent fracture permeability, R is the proportion of the horizontal fracture length along the seepage direction, b is the aperture of a single equivalent fracture, c1 is the influence coefficient of roughness and tortuosity on the fracture permeability, h is the effective thickness of the reservoir, and K m is the matrix permeability; Calculating the equivalent fracture seepage velocity using the equivalent fracture permeability includes: Using the formula to calculate the equivalent fracture seepage velocity, where v f is the crossflow velocity of the injected water between wells, μ is the viscosity of the injected water, Δp is the injection-production pressure difference, L is the injection-production well spacing, ρ is the density of the mixed fluid, g is the acceleration due to gravity, and α is the fracture dip angle; Calculating the matrix seepage velocity using the matrix permeability includes: Using the formula calculate the seepage velocity of the matrix, where v m is the seepage velocity of the injected water between wells; Determining the equivalent fracture water production and equivalent fracture liquid production according to the equivalent fracture seepage velocity includes: Using the formula to calculate the equivalent fracture water production. In the formula, Q fw is the equivalent fracture water production, n is the number of horizontal fracture layers, m is the fracture-vug volume coefficient, W is the total width of the seepage cross-section, P is the proportion of the width occupied by fractures in the seepage cross-section, b max is the maximum aperture of the fracture occupied by the injected water, b(t) is the aperture of the fracture occupied by the injected water at time t, f(b) is the probability density function of the average total aperture b of the fracture, c is the influence coefficient of roughness and tortuosity on the fracture permeability, where is the logarithmic mean of the fracture, σ is the logarithmic standard deviation of the fracture aperture; Using the formula to calculate the equivalent fracture liquid production. In the formula, Q f is the equivalent fracture liquid production; Determining the matrix water production and matrix liquid production according to the matrix seepage velocity includes: Calculate the matrix water production using the formula where Q mw is the matrix water production, h is the reservoir thickness, φ is the reservoir porosity, and f w0 is the initial water saturation of the reservoir; Use the formula to calculate the matrix liquid production rate, where Q m is the matrix liquid production rate.

4. The method according to claim 3, wherein Obtaining the water cut change curve of the water flooding process based on the water flooding process parameters includes: Based on the water flooding process, the water cut calculation model is transformed into a water flooding water cut calculation model; the water flooding water cut calculation model is In the formula,[[]] Substituting the production parameters corresponding to the target reservoir into the water cut calculation model to obtain the water cut values at different times of the target reservoir; Fitting the water cut change curve of the water flooding process based on the water cut values.

5. The method according to claim 1, characterized in that Inverting the inter-well seepage channel through the water cut change curve of the water flooding process includes: Determining equivalent fracture characteristic parameters based on the water cut change curve of the water flooding process; the equivalent fracture characteristic parameters include at least one of the permeability ratio of a single equivalent fracture, the thickness of the inter-well equivalent channel, and the variance of the equivalent fracture aperture.

6. The method according to claim 1, wherein The target reservoir satisfies the following conditions: The horizontal fractures and the matrix connected in series in the equivalent fracture have equal widths, and outside the equivalent fracture is pure matrix, and / or, The water flooding process is equivalent to piston displacement, and / or, The apertures of different equivalent fractures are different, and the apertures of all equivalent fractures follow a lognormal distribution.

7. An inter-well seepage channel characterization device based on water flooding, characterized in that Including: A geological parameter acquisition module for obtaining geological parameters of a target reservoir; A parameter calculation module for calculating equivalent fracture seepage parameters and matrix seepage parameters in the target reservoir based on the geological parameters; The equivalent fracture is formed by connecting horizontal fractures and matrix in series in the target reservoir; the equivalent fractures in the target reservoir constitute the inter-well seepage channel; A water cut calculation model determination module for determining a water cut calculation model according to the equivalent fracture seepage parameters and matrix seepage parameters; A water cut change curve acquisition module for obtaining the water cut change curve of the water flooding process based on the water flooding process parameters; An inter-well seepage channel inversion module is used to invert the inter-well seepage channel through the water cut change curve during the water flooding process; Among them, the equivalent fracture seepage parameters include the equivalent fracture water production and the equivalent fracture liquid production; the matrix seepage parameters include the matrix water production and the matrix liquid production; calculating the equivalent fracture seepage parameters and the matrix seepage parameters in the target reservoir based on the geological parameters includes: calculating the equivalent fracture permeability based on the geological parameters; calculating the equivalent fracture seepage velocity using the equivalent fracture permeability; calculating the matrix seepage velocity using the matrix permeability; determining the equivalent fracture water production and the equivalent fracture liquid production according to the equivalent fracture seepage velocity; determining the matrix water production and the matrix liquid production according to the matrix seepage velocity; The equivalent fracture seepage parameters include at least one of equivalent fracture water production, equivalent fracture oil production, matrix water production, and matrix oil production; the water cut calculation model is where f w is the water cut, Q fw is the equivalent fracture water production, Q f is the equivalent fracture liquid production, Q mw is the matrix water production, Q m is the matrix liquid production.

8. A computer storage medium having computer programs / instructions stored thereon, characterized in that, The computer program / instructions, when executed, implement the method according to any one of claims 1-6.

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